阅读说明：本技术 闸阀 (Gate valve ) 是由 和田慎一 井上英晃 柴山浩司 和出拓也 古濑晴邦 于 2019-03-20 设计创作，主要内容包括：本发明的闸阀具备：阀箱,具有中空部和第一开口部及第二开口部,所述第一开口部及第二开口部隔着所述中空部彼此相对设置且成为连通的流道；中立阀体,配置在所述阀箱的所述中空部内且能关闭所述第一开口部；旋转轴,用于在使所述中立阀体相对于所述第一开口部处于关闭状态的阀关闭位置与使所述中立阀体处于从所述第一开口部退避的开放状态的阀开放位置之间转动所述中立阀体；旋转装置,由用于使所述旋转轴旋转的齿条小齿轮及用于驱动所述齿条小齿轮的旋转气缸构造；关闭解除驱动部,由进行解除所述中立阀体的关闭的操作的关闭解除气缸构造；和时序回路,能够依次进行解除所述中立阀体的关闭的操作和所述中立阀体的旋转操作。(The gate valve of the present invention comprises: a valve box having a hollow portion, and a first opening portion and a second opening portion which are provided opposite to each other with the hollow portion therebetween and form a communicating flow passage; a neutral valve body which is disposed in the hollow portion of the valve housing and can close the first opening portion; a rotation shaft for rotating the neutral valve body between a valve closing position at which the neutral valve body is in a closed state with respect to the first opening portion and a valve opening position at which the neutral valve body is in an open state in which the neutral valve body is retracted from the first opening portion; a rotating device configured by a rack pinion for rotating the rotating shaft and a rotating cylinder for driving the rack pinion; a closure release driving unit having a closure release cylinder structure for performing an operation of releasing the closure of the neutral valve body; and a sequence circuit capable of sequentially performing an operation of releasing the closing of the neutral valve body and a rotation operation of the neutral valve body.)

1. A gate valve is provided with:

a valve box having a hollow portion, and a first opening portion and a second opening portion which are provided opposite to each other with the hollow portion therebetween and form a communicating flow passage;

a neutral valve body which is disposed in the hollow portion of the valve housing and can close the first opening portion;

a rotation shaft for rotating the neutral valve body between a valve closing position at which the neutral valve body is in a closed state with respect to the first opening portion and a valve opening position at which the neutral valve body is in an open state in which the neutral valve body is retracted from the first opening portion;

a rotating device configured by a rack pinion for rotating the rotating shaft and a rotating cylinder for driving the rack pinion;

a closure release driving unit having a closure release cylinder structure for performing an operation of releasing the closure of the neutral valve body; and

a timing circuit capable of sequentially performing an operation of releasing the closing of the neutral valve body and a rotation operation of the neutral valve body,

the rotary cylinder has:

a biasing portion for causing the neutral valve body to perform a closing operation;

a piston capable of opening and closing; and

a first pressure space and a second pressure space arranged in series in an operation direction of the piston and capable of causing the piston to perform a closing operation,

the timing loop has: a pneumatic dual chamber slide valve; and a speed regulating valve composed of a one-way valve and a flow regulating valve,

the sequence circuit supplies compressed air as damping air to the first pressure space when the gate valve is opened by a system of driving compressed air supply,

when the drive of the closure release cylinder is finished, the first pressure space is set to a non-pressurized state, the second pressure space is set to a pressurized state, and the opening operation of the revolving cylinder is started, and the impact is relieved by the air in the first pressure space immediately before the neutral valve body reaches the valve opening position,

when the gate valve is closed by releasing the supply of the driving compressed air, the first pressure space and the second pressure space are set to a non-pressurized state, the closing operation of the revolving cylinder is started by the biasing force of the biasing portion, and the impact is relieved by the damping air in the second pressure space immediately before the neutral valve body reaches the valve closing position,

when the rotation operation of the neutral valve body is ended, the closing operation of the neutral valve body is started by the closing release cylinder.

2. A gate valve is provided with:

a valve box having a hollow portion, and a first opening portion and a second opening portion which are provided opposite to each other with the hollow portion therebetween and form a communicating flow passage;

a neutral valve body which is disposed in the hollow portion of the valve housing and can close the first opening portion;

a rotary shaft that functions as a position switching unit that operates the neutral valve body between a valve closing position at which the neutral valve body is in a closed state with respect to the first opening portion and a valve opening position at which the neutral valve body is in an open state retracted from the first opening portion, and that has an axis extending in a flow path direction;

a rotating device configured by a rack pinion for rotating the rotating shaft and a rotating cylinder for driving the rack pinion;

a closure release driving unit having a closure release cylinder structure for performing an operation of releasing the closure of the neutral valve body; and

a timing circuit capable of sequentially performing an operation of releasing the closing of the neutral valve body and a rotation operation of the neutral valve body,

the neutral valve body has a neutral valve portion connected to the position switching portion and a movable valve portion connected to the neutral valve portion so that a position in the flow path direction can be changed,

the movable valve portion includes: a first movable valve part that is provided around the movable valve part, is provided with a seal part that is in close contact with an inner surface of the valve housing around the first opening, and is connected to the neutral valve part so that a position in the flow path direction can be changed; and a second movable valve portion slidable in the flow passage direction with respect to the first movable valve portion,

the gate valve includes a plurality of first biasing portions built in the valve housing, and a second biasing portion and a third biasing portion arranged between the first movable valve portion and the second movable valve portion,

the third urging portion connects the first movable valve portion to the neutral valve portion so as to be able to change the position in the flow channel direction, and urges the first movable valve portion toward the center position in the flow channel direction,

the plurality of first urging portions have a function of being capable of being driven by the closure canceling cylinder and bringing the seal portion into close contact with the inner surface of the valve housing around the first opening portion by urging the first movable valve portion toward the first opening portion in the flow passage direction,

the second urging portion is driven so that the thickness dimensions of the first movable valve portion and the second movable valve portion in the flow channel direction can be adjusted,

the rotary cylinder has:

a biasing portion for causing the neutral valve body to perform a closing operation;

a piston capable of opening and closing; and

a first pressure space and a second pressure space arranged in series in an operation direction of the piston and capable of causing the piston to perform a closing operation,

the timing loop has: a pneumatic dual chamber slide valve; and a speed regulating valve composed of a one-way valve and a flow regulating valve,

the sequence circuit supplies compressed air as damping air to the first pressure space when the gate valve is opened by a system of driving compressed air supply,

when the drive of the closure release cylinder is finished, the first pressure space is set to a non-pressurized state, the second pressure space is set to a pressurized state, and the opening operation of the revolving cylinder is started, and the impact is relieved by the air in the first pressure space immediately before the neutral valve body reaches the valve opening position,

when the gate valve is closed by releasing the supply of the driving compressed air, the first pressure space and the second pressure space are set to a non-pressurized state, the closing operation of the revolving cylinder is started by the biasing force of the biasing portion, and the impact is relieved by the damping air in the second pressure space immediately before the neutral valve body reaches the valve closing position,

when the rotation operation of the neutral valve body is ended, the closing operation of the neutral valve body is started by the closing release cylinder.

3. A gate valve is provided with:

a valve box having a hollow portion, and a first opening portion and a second opening portion which are provided opposite to each other with the hollow portion therebetween and form a communicating flow passage;

a neutral valve body which is disposed in the hollow portion of the valve housing and can close the first opening portion;

a rotary shaft that functions as a position switching unit that operates the neutral valve body between a valve closing position at which the neutral valve body is in a closed state with respect to the first opening portion and a valve opening position at which the neutral valve body is in an open state retracted from the first opening portion, and that has an axis extending in a flow path direction;

a rotating device configured by a rack pinion for rotating the rotating shaft and a rotating cylinder for driving the rack pinion;

a seal ring provided around the first opening portion so as to be slidable in the flow direction, the seal ring being capable of adjusting an opening degree of the flow passage in a closed state in which the seal ring closes the flow passage by coming into contact with the neutral valve body at the valve closing position and in an open state in which the neutral valve body is at the valve opening position;

a closing release cylinder which is provided in the valve box and is used for releasing the closed state of the seal ring;

a seal ring biasing portion that biases the seal ring in a direction of abutting against the neutral valve body; and

a timing circuit capable of sequentially performing an operation of releasing the closing of the neutral valve body and a rotation operation of the neutral valve body,

the rotary cylinder has:

a biasing portion for causing the neutral valve body to perform a closing operation;

a piston capable of opening and closing; and

a first pressure space and a second pressure space arranged in series in an operation direction of the piston and capable of causing the piston to perform a closing operation,

the timing loop has: a pneumatic dual chamber slide valve; and a speed regulating valve composed of a one-way valve and a flow regulating valve,

the sequence circuit supplies compressed air as damping air to the first pressure space when the gate valve is opened by a system of driving compressed air supply,

when the drive of the closure release cylinder is finished, the first pressure space is set to a damping pressure state, the second pressure space is set to a pressurized state, and the opening operation of the revolving cylinder is started, and the impact is relieved by the air in the first pressure space immediately before the neutral valve body reaches the valve opening position,

when the gate valve is closed by releasing the supply of the driving compressed air, the first pressure space is set to a damping pressure state, the second pressure space is set to a non-pressurized state, and the closing operation of the revolving cylinder is started by the biasing force of the biasing portion, and the impact is relieved by the damping air in the second pressure space immediately before the neutral valve body reaches the valve closing position,

when the rotation operation of the neutral valve body is ended, the closing operation of the neutral valve body is started by the closing release cylinder.

Technical Field

The present invention relates to a gate valve of a pendulum type or the like suitable for sliding a valve body (valve plate) in addition to an operation of opening and closing a flow passage using the valve body. In particular, the present invention relates to a gate valve comprising: this gate valve is used to block (close) a flow path connecting two spaces having different pressures and a flow path connecting two spaces performing different processes in a vacuum apparatus or the like, and to open the blocked state (connect the two spaces).

The present application claims priority based on patent application No. 2018-069863, filed in japan on 30/3/2018, and the contents of which are incorporated herein by reference.

Background

A gate valve is provided in a vacuum apparatus or the like to block two spaces of different vacuum degrees, such as between a chamber and a pipe, between a pipe and a pipe, or between a pipe and a pump or the like, and to connect the two spaces that are blocked. Various types of gate valves are known as such gate valves.

For example, the following structures are known: the valve sheet is inserted to a valve opening/closing position of the flow passage by sliding the valve sheet, and is operated to block the flow passage (valve closing operation), or is operated to connect the flow passage (valve opening operation), and is further retracted from the flow passage to a retracted position in the valve housing by sliding the valve sheet. As a valve having such a structure, a pendulum type, a linear motion type, a gate type, or the like is known.

The pendulum type slide valve has the following structure: that is, the pendulum gate valve is provided with: a valve box having a hollow portion and formed with a first opening and a second opening for constructing a flow passage; a support body fixedly provided on the rotation shaft in the hollow portion and expanding in a direction parallel to a plane perpendicular to the rotation shaft; and a valve body (a valve sheet in the case of a structure in which a seal ring plate is provided in an opening) fixedly provided on the support body. The slide valve (gate valve) rotates the valve body by rotating the rotary shaft, and inserts the valve body into a valve opening/closing position of an opening (flow passage) or retracts the valve body to a retracted position where the opening is not formed.

The present inventors have developed a gate valve having a structure capable of increasing the closing area of a slide valve driven by compressed air supply and capable of performing a highly reliable shut-off operation with a simple structure, and have filed a patent application (patent document 1).

Further, as a pendulum gate valve, there is known a structure in which: that is, the hollow portion of the housing is provided with: a valve plate rotatable on the rotary shaft; a slidable seal ring plate disposed in the opening of the housing; and an actuator for sliding the sealing ring plate on a flange formed integrally with the housing. In this gate valve, the seal ring plate is brought into contact with the valve sheet and pressed against the valve sheet to close the flow passage, or the seal ring plate is separated from the valve sheet to open the flow passage (see, for example, patent document 2).

The actuator of the pendulum gate valve has a structure in which a bolt, an annular chamber (cylinder), a piston, and a spring are arranged in series in the sliding direction of a seal ring plate. Therefore, when the flow passage is closed, the restoring force generated in the spring is transmitted to the seal ring plate via the piston, the cylinder, and the bolt.

It is known that the above gate valve uses compressed air, for example, when the valve body rotates.

Further, although the valve disclosed in patent document 3 is different from a gate valve using compressed air in terms of valve type, the following highly safe valve is required: this valve is a normally closed (normally closed) valve as described in patent document 3, which is capable of automatically closing a flow passage when driving power supply, compressed air supply, or the like is lost, and thus is in a valve closed position.

The normally closed state is a state in which compressed air (compressed air) for driving a valve body or the like does not act when a valve closing operation is performed, and the like, and is automatically brought into a closed state when the valve is in an open state, and the flow passage is maintained in a closed state when the valve is in a closed state.

Patent document 1: japanese patent laid-open No. 5727841

Patent document 2: japanese patent No. 3655715

Patent document 3: japanese patent laid-open publication No. 2013-190028

However, the slide valve described in patent document 1 developed by the present inventors does not have such a normally closed structure.

In the gate valve that is pneumatically driven as described in patent document 2, when the normally closed structure is realized using a spring member, there is a possibility that a movable portion such as a driving portion or a valve body may come into contact with another member when the operation is stopped or the like by the biasing force of the spring member that performs the normally closed operation.

In recent years, with the rapid opening and closing operation of the gate valve and the increase in the area closed by the gate valve, the problem of insufficient prevention of the occurrence of impact due to the operation of the gate valve, which causes the occurrence of particles, has been highlighted. In order to solve this problem, it is also conceivable to provide a mechanical mechanism such as a damper in the gate valve.

However, in an apparatus for installing a gate valve, a manufacturing line, and the like, an installation posture of the gate valve is set according to an apparatus and a manufacturing line using the gate valve, and the installation posture of the gate valve is various. Therefore, the installation posture of the gate valve cannot be determined in general when the gate valve is manufactured. Therefore, it is not practical to provide the damper to the gate valve by considering all installation postures of the gate valve in advance. The reason is that the gate valve changes the operation direction during the opening and closing operation according to the installation posture thereof. Further, since a mechanical mechanism such as a damper is provided in the gate valve, the amount of impact generated in accordance with the opening/closing operation varies, but the structure, number, performance, and the like of the mechanical mechanism need to be set in accordance with the impact absorption force of the mechanical mechanism. A plurality of installation structures are conceivable with respect to installation postures of the gate valve in the apparatus and the manufacturing line, but it is not practical to prepare a plurality of types of dampers according to the installation structures.

In addition, in the slide valve described in patent document 1 developed by the present inventors, three systems of compressed air are used as the drive control compressed air, but there is a demand for controlling the opening and closing operation of the slide valve only by the pressure of the drive control compressed air supplied to one system, that is, only by the opening/closing (on/off) of the compressed air of one system.

Meanwhile, the gate valve is increased in size in order to enable a blocking operation over a large area, but the pressure of the control fluid (compressed air or the like) supplied to the gate valve is not increased by this increase. Therefore, in order to drive a movable portion such as a valve body having an increased weight, the output of the movable portion needs to be increased, and the volume of a member constituting the gate valve tends to be large. However, space saving is required in apparatuses and manufacturing lines in which gate valves are installed, and there is a demand for space saving and miniaturization of components constituting gate valves.

Disclosure of Invention

The present invention has been made in view of such conventional circumstances, and an object thereof is to provide a gate valve having a normally closed structure, which can prevent the occurrence of particles due to an impact caused by the operation of the gate valve, save the space of parts, and can be operated only by supplying compressed air for driving of one system, and can perform a blocking operation with high reliability, thereby achieving a reduction in the weight of a movable valve portion.

In order to solve the above problem, a gate valve according to a first aspect of the present invention includes: a valve box having a hollow portion, and a first opening portion and a second opening portion which are provided opposite to each other with the hollow portion therebetween and form a communicating flow passage; a neutral valve body which is disposed in the hollow portion of the valve housing and can close the first opening portion; a rotation shaft for rotating the neutral valve body between a valve closing position at which the neutral valve body is in a closed state with respect to the first opening portion and a valve opening position at which the neutral valve body is in an open state in which the neutral valve body is retracted from the first opening portion; a rotating device configured by a rack pinion for rotating the rotating shaft and a rotating cylinder for driving the rack pinion; a closure release driving unit having a closure release cylinder structure for performing an operation of releasing the closure of the neutral valve body; and a sequence circuit capable of sequentially performing an operation of releasing the closing of the neutral valve body and a rotation operation of the neutral valve body. The rotary cylinder has: a biasing portion for causing the neutral valve body to perform a closing operation; a piston capable of opening and closing; and a first pressure space and a second pressure space which are arranged in series in the operating direction of the piston and which enable the piston to perform a closing operation, and which enable the piston to perform an opening operation. The timing loop has: a pneumatic dual chamber slide valve; and a speed regulating valve composed of a check valve and a flow regulating valve. The sequence circuit supplies compressed air as damping air to the first pressure space when the gate valve is opened by a supply of driving compressed air of one system, sets the first pressure space to a non-pressurized state and the second pressure space to a pressurized state when the drive of the closure release cylinder is finished, and starts the opening operation of the revolving cylinder, and relieves the shock by the air of the first pressure space immediately before the neutral valve body reaches the valve opening position, and sets the first pressure space and the second pressure space to the non-pressurized state when the gate valve is closed by the release of the supply of driving compressed air, and starts the closing operation of the revolving cylinder by the biasing force of the biasing portion immediately before the neutral valve body reaches the valve closing position, the impact is relieved by the damping air of the second pressure space, and when the rotation operation of the neutral valve body is finished, the closing operation of the neutral valve body is started by the closing release cylinder.

In order to solve the above problem, a second aspect of the present invention provides a gate valve including: a valve box having a hollow portion, and a first opening portion and a second opening portion which are provided opposite to each other with the hollow portion therebetween and form a communicating flow passage; a neutral valve body which is disposed in the hollow portion of the valve housing and can close the first opening portion; a rotary shaft that functions as a position switching unit that operates the neutral valve body between a valve closing position at which the neutral valve body is in a closed state with respect to the first opening portion and a valve opening position at which the neutral valve body is in an open state retracted from the first opening portion, and that has an axis extending in a flow path direction; a rotating device configured by a rack pinion for rotating the rotating shaft and a rotating cylinder for driving the rack pinion; a closure release driving unit having a closure release cylinder structure for performing an operation of releasing the closure of the neutral valve body; and a sequence circuit capable of sequentially performing an operation of releasing the closing of the neutral valve body and a rotation operation of the neutral valve body. The neutral valve body has a neutral valve portion connected to the position switching portion and a movable valve portion connected to the neutral valve portion so that a position in the flow path direction can be changed. The movable valve portion includes: a first movable valve part that is provided around the movable valve part, is provided with a seal part that is in close contact with an inner surface of the valve housing around the first opening, and is connected to the neutral valve part so that a position in the flow path direction can be changed; and a second movable valve portion slidable in the flow passage direction with respect to the first movable valve portion. The gate valve includes a plurality of first biasing portions built into the valve housing, and a second biasing portion and a third biasing portion arranged between the first movable valve portion and the second movable valve portion, and the third biasing portion connects the first movable valve portion to the neutral valve portion so as to be able to change a position in the flow path direction, and biases the first movable valve portion toward a center position in the flow path direction. The plurality of first biasing portions have a function of being capable of being driven by the closure canceling cylinder and bringing the seal portion into close contact with the inner surface of the valve housing around the first opening portion by biasing the first movable valve portion toward the first opening portion in the flow passage direction. The second biasing portion is driven so that the thickness dimensions of the first movable valve portion and the second movable valve portion in the flow channel direction can be adjusted. The rotary cylinder has: a biasing portion for causing the neutral valve body to perform a closing operation; a piston capable of opening and closing; and a first pressure space and a second pressure space which are arranged in series in the operating direction of the piston and which enable the piston to perform a closing operation, and which enable the piston to perform an opening operation. The timing loop has: a pneumatic dual chamber slide valve; and a speed regulating valve composed of a check valve and a flow regulating valve. The sequence circuit supplies compressed air as damping air to the first pressure space when the gate valve is opened by a supply of driving compressed air of one system, sets the first pressure space to a non-pressurized state and the second pressure space to a pressurized state when the drive of the closure release cylinder is finished, and starts the opening operation of the revolving cylinder, and relieves the shock by the air of the first pressure space immediately before the neutral valve body reaches the valve opening position, and sets the first pressure space and the second pressure space to the non-pressurized state when the gate valve is closed by the release of the supply of driving compressed air, and starts the closing operation of the revolving cylinder by the biasing force of the biasing portion immediately before the neutral valve body reaches the valve closing position, the impact is relieved by the damping air of the second pressure space, and when the rotation operation of the neutral valve body is finished, the closing operation of the neutral valve body is started by the closing release cylinder.

In order to solve the above problem, a gate valve according to a third aspect of the present invention includes: a valve box having a hollow portion, and a first opening portion and a second opening portion which are provided opposite to each other with the hollow portion therebetween and form a communicating flow passage; a neutral valve body which is disposed in the hollow portion of the valve housing and can close the first opening portion; a rotary shaft that functions as a position switching unit that operates the neutral valve body between a valve closing position at which the neutral valve body is in a closed state with respect to the first opening portion and a valve opening position at which the neutral valve body is in an open state retracted from the first opening portion, and that has an axis extending in a flow path direction; a rotating device configured by a rack pinion for rotating the rotating shaft and a rotating cylinder for driving the rack pinion; a seal ring provided around the first opening portion so as to be slidable in the flow direction, the seal ring being capable of adjusting an opening degree of the flow passage in a closed state in which the seal ring closes the flow passage by coming into contact with the neutral valve body at the valve closing position and in an open state in which the neutral valve body is at the valve opening position; a closing release cylinder which is provided in the valve box and is used for releasing the closed state of the seal ring; a seal ring biasing portion that biases the seal ring in a direction of abutting against the neutral valve body; and a sequence circuit capable of sequentially performing an operation of releasing the closing of the neutral valve body and a rotation operation of the neutral valve body. The rotary cylinder has: a biasing portion for causing the neutral valve body to perform a closing operation; a piston capable of opening and closing; and a first pressure space and a second pressure space which are arranged in series in the operating direction of the piston and which enable the piston to perform a closing operation, and which enable the piston to perform an opening operation. The timing loop has: a pneumatic dual chamber slide valve; and a speed regulating valve composed of a check valve and a flow regulating valve. The sequence circuit supplies compressed air as damping air to the first pressure space when the gate valve is opened by supply of driving compressed air of one system, sets the first pressure space to a damping pressure state and the second pressure space to a pressurized state when the drive of the closure release cylinder is finished, and starts the opening operation of the revolving cylinder, and reduces the shock by the air of the first pressure space immediately before the neutral valve body reaches the valve opening position, and sets the first pressure space to a damping pressure state and the second pressure space to a non-pressurized state when the gate valve is closed by release of the supply of driving compressed air, and starts the closing operation of the revolving cylinder by the biasing force of the biasing portion immediately before the neutral valve body reaches the valve closing position, the impact is relieved by the damping air of the second pressure space, and when the rotation operation of the neutral valve body is finished, the closing operation of the neutral valve body is started by the closing release cylinder.

In the gate valve according to the aspect of the present invention, the timing circuit may include a closing detection shaft (rotation operation end detection open/close valve), and the neutral valve body may be configured to perform a closing release operation.

The gate valve according to the aspect of the present invention has a normally closed structure, and can sequentially perform an operation of releasing the closing of the neutral valve body and a rotation operation of the neutral valve body by supplying and releasing a single system of driving compressed air in a time-series circuit, and can alleviate an impact caused by the operation of the gate valve by damping air in the first pressure space, thereby preventing generation of particles.

According to the gate valve of the aspect of the present invention, the following effects can be obtained that are obtained in a gate valve having a normally closed structure: that is, the gate valve prevents the generation of particles due to an impact caused by the operation of the gate valve, saves the space of parts, can be operated only by one system of supply of compressed driving air, can perform a highly reliable blocking operation, and can reduce the weight of the movable valve portion.

Drawings

Fig. 1 is a cross-sectional view showing a gate valve structure according to a first embodiment of the present invention.

Fig. 2 is a vertical cross-sectional view showing a gate valve structure according to a first embodiment of the present invention, and is a view showing a case where a valve body is disposed at a position where a retreat operation is possible.

Fig. 3 is an enlarged view showing a main part of a part located in the vicinity of the annular cylinder in fig. 2.

Fig. 4 is a vertical cross-sectional view showing a gate valve structure according to a first embodiment of the present invention, and is a view showing a state in which a valve body is arranged at a valve-closed position.

Fig. 5 is an enlarged view showing a main portion of the part located near the main spring in fig. 4.

Fig. 6 is a vertical cross-sectional view showing a gate valve structure according to a first embodiment of the present invention, and is a view showing a state in which a valve body is disposed at a retracted position.

Fig. 7A is an enlarged view of a main part of a member located in the vicinity of the rotation shaft and the fluid path ring in the gate valve according to the first embodiment of the present invention, and is a cross-sectional view taken along the radial direction of the rotation shaft.

Fig. 7B is an enlarged view of a main part of a member located in the vicinity of the rotation shaft and the fluid path ring in the gate valve according to the first embodiment of the present invention, and is a cross-sectional view taken along the axial direction of the rotation shaft.

Fig. 8 is a sectional view (extended position) showing the rotary shaft drive mechanism according to the first embodiment of the present invention.

Fig. 9 is a sectional view (retracted position) showing the rotary shaft drive mechanism according to the first embodiment of the present invention.

Fig. 10 is an enlarged sectional view of a main portion showing the rack member and the sliding bearing.

Fig. 11 is an enlarged view of a main portion showing a meshing portion of the rack member and the pinion.

Fig. 12A is an enlarged view of a main portion showing a fitting portion of the rotary shaft and the neutral valve body, and is a cross-sectional view taken along a radial direction of the rotary shaft.

Fig. 12B is an enlarged view of a main portion showing a fitting portion of the rotary shaft and the neutral valve body, and is a sectional view taken along the axial direction of the rotary shaft.

Fig. 13 is an enlarged view showing a main part of a member located in the vicinity of the connecting pin.

Fig. 14 is a circuit diagram showing a drive sequence mechanism according to the first embodiment of the present invention.

Fig. 15 is a diagram showing a pressure state in the drive sequence mechanism shown in fig. 14.

Fig. 16 is a diagram showing a pressure state in the drive sequence mechanism shown in fig. 14.

Fig. 17 is a diagram showing a pressure state in the drive sequence mechanism shown in fig. 14.

Fig. 18 is a diagram showing a pressure state in the drive sequence mechanism shown in fig. 14.

Fig. 19 is an enlarged view showing a main part of a member located in the vicinity of the fastening member of the first embodiment of the present invention.

Fig. 20 is a cross-sectional view showing a gate valve structure according to a second embodiment of the present invention.

Fig. 21 is a vertical cross-sectional view showing a gate valve structure according to a second embodiment of the present invention, and is a view showing a case where a valve body is disposed at a position (FREE) where a retracting operation is possible.

Fig. 22 is an enlarged view showing a main portion along a line a-O in fig. 20, and is a view showing a case where the valve body is disposed at a position where the retracting operation (FREE) is possible.

Fig. 23 is an enlarged view showing a main portion along a line B-O in fig. 20, and is a view showing a case where the valve body is disposed at a position (FREE) where the retracting operation is possible.

Fig. 24 is an enlarged view showing a main portion along a line C-O in fig. 20, and is a view showing a case where the valve body is disposed at a position (FREE) where the retracting operation is possible.

Fig. 25 is an enlarged view showing a main part of the C biasing portion in fig. 21, and is a view showing a case where the valve body is disposed at a position (FREE) where the retracting operation is possible.

Fig. 26 is a vertical cross-sectional view showing a gate valve structure according to a second embodiment of the present invention, and is a view showing a state in which a valve body is disposed at a valve closing position (no positive pressure or differential pressure).

Fig. 27 is a vertical sectional view showing a gate valve structure according to a third embodiment of the present invention.

Detailed Description

Next, a gate valve according to a first embodiment of the present invention will be described with reference to the drawings.

In the drawings used in the following description, the dimensions and proportions of the components are appropriately set to be different from the actual dimensions and proportions so that the components are of a size that can be recognized in the drawings.

The technical scope of the present invention is not limited to the embodiments described below, and various changes may be made without departing from the spirit of the present invention.

(first embodiment)

Fig. 1 is a plan view showing a gate valve structure according to the present embodiment. Fig. 2 is a vertical cross-sectional view showing a gate valve structure according to a first embodiment of the present invention, and is a view showing a case where a valve body is disposed at a position where a retreat operation is possible. Fig. 3 is an enlarged view showing a main portion in a region near a connecting portion between the neutral valve portion and the first movable valve portion and the first urging portion and the second urging portion shown in fig. 2. Fig. 4 is a vertical sectional view showing the structure of the gate valve according to the present embodiment, and is a view showing a state in which the neutral valve body is arranged at the valve-closed position. Fig. 5 is an enlarged view showing a main portion in the region near the connection portion between the neutral valve portion and the first movable valve portion and the first urging portion and the second urging portion shown in fig. 4. Fig. 6 is a vertical cross-sectional view showing a gate valve structure according to a first embodiment of the present invention, and is a view showing a state in which a valve body is disposed at a retracted position. Fig. 7A is an enlarged view of a main part of a member located in the vicinity of the rotation shaft and the fluid path ring in the gate valve according to the first embodiment of the present invention, and is a cross-sectional view taken along the radial direction of the rotation shaft. Fig. 7B is an enlarged view of a main part of a member located in the vicinity of the rotation shaft and the fluid path ring in the gate valve according to the first embodiment of the present invention, and is a cross-sectional view taken along the axial direction of the rotation shaft.

[ pendulum type gate valve ]

As shown in fig. 1 to 6, the gate valve 1 of the first embodiment is a pendulum type slide valve.

The gate valve 1 of the present embodiment includes: a valve box 10 provided with a first opening portion 12a and a second opening portion 12b opposing each other; a rotary shaft 20 as a switching unit penetrating the valve housing 10; a connecting member 91 fixed to the rotary shaft 20; a neutral valve portion 30 connected to the rotary shaft 20 via the connecting member 91; a movable valve portion 40 connected to the neutral valve portion 30 so as to be movable in the axial direction of the rotary shaft 20; a main spring (first urging portion) 70 for increasing the thickness of the movable valve portion 40 by urging the movable valve portion 40 in the thickness direction of the movable valve portion 40; a driving annular cylinder (closing release cylinder) 80 that is extendable in a direction opposite to the biasing direction of the main spring 70; and an auxiliary spring (third biasing portion) 90 for position regulation, which is used to dispose the movable valve portion 40 at a position close to the center position of the valve housing 10.

The neutral valve portion 30 and the movable valve portion 40 constitute a neutral valve body 5. The movable valve portion 40 is configured by a movable valve portion (second movable valve portion) 50 and a movable valve frame portion (first movable valve portion) 60. A flow passage H is defined from the first opening 12a toward the second opening 12 b. In the following description, the direction along the flow channel H is sometimes referred to as a flow channel direction H.

When the rotary shaft 20 rotates in the direction indicated by reference numeral a1 (the direction intersecting the direction of the flow path H), the neutral valve portion 30 fixed to the rotary shaft 20 by the connecting member 91 also rotates in the direction a1 in accordance with the rotation. Further, since the movable valve portion 40 is slidably connected to the neutral valve portion 30 only in the thickness direction, the movable valve portion 40 and the neutral valve portion 30 rotate integrally.

By rotating the neutral valve portion 30 in this manner, the movable valve portion 40 moves in a pendulum motion from the retracted position E1 located in the hollow portion 11 where the flow path H is not provided to the valve closed position E2 of the flow path H that is a position corresponding to the first opening portion 12 a.

When the main spring 70 is caused to act in the expansion direction to perform an operation of expanding the thickness dimension of the movable valve portion 40 in the flow path H direction (valve closing operation), the sealing portion 61 of the movable valve frame portion 60 and the reaction force transmitting portion 59 of the movable valve plate portion 50 press the inner surface 15a and the inner surface 15b of the valve housing 10, respectively, as described later, and the movable valve portion 40 closes the flow path H.

On the other hand, when the annular cylinder (second biasing portion) 80 is caused to act, the pressing force of the annular cylinder 80 becomes larger than the biasing force of the main spring 70, and the thickness dimension of the movable valve portion 40 is contracted in the flow path H direction. Thereby, the front surface and the back surface of the movable valve portion 40 are separated from the inner surface 15a and the inner surface 15b of the valve housing 10 (releasing operation). Thereafter, when the rotary shaft 20 is rotated in the direction indicated by reference numeral a2 (retracting operation), the neutral valve portion 30 and the movable valve portion 40 are also rotated in the direction a2 in accordance with the rotation.

By the releasing operation and the retracting operation, the movable valve portion 40 is retracted from the valve opening/closing position to the retracting position, and the valve opening operation is performed with the movable valve portion 40 in the valve opening state.

[ valve box 10]

The valve housing 10 is constructed of a frame having a hollow portion 11. The frame is provided with a first opening 12a on the upper surface in the figure and a second opening 12b on the lower surface in the figure.

The gate valve 1 is inserted between a space (first space) where the first opening 12a is exposed and a space (second space) where the second opening 12b is exposed. The gate valve 1 is configured to close (close) a flow path H connecting the first opening 12a and the second opening 12b, that is, a flow path H connecting the first space and the second space, and to open the closed state (connecting the first space and the second space).

The hollow portion 11 of the valve housing 10 is provided with a rotary shaft 20, a neutral valve portion 30, a movable valve portion 40, a main spring (first urging portion) 70, an annular cylinder (second urging portion) 80, and an auxiliary spring (third urging portion) 90.

[ rotating shaft 20, fluid path rings 17, 18]

The rotary shaft 20 is provided to extend in a state substantially parallel to the flow passage H, penetrate the valve housing 10, and be rotatable.

A coupling member 91 is fixed to the rotary shaft 20. The connecting member 91 is, for example, a substantially flat plate-like member. As shown in fig. 7B, is fixed to one end 20a of the rotary shaft 20 by a bolt 92. A projection 93 is formed on one end side of the connecting member 91 in the flow path direction H. In other words, the protrusion 93 extends in a direction perpendicular to the flow path direction H, and the connection member 91 has a substantially T-shaped cross-sectional shape.

As shown in fig. 7A and 7B, the rotary shaft 20 is rotatably supported by bearings 16A and 16B such as bearings through the valve housing 10 in the housing 14 fixedly provided in the valve housing 10. The bearings 16A and 16B are disposed as far apart as possible in the direction along the axis LL of the rotary shaft 20.

The housing 14 is fixed to the valve housing 10 in a sealed state and penetrates therethrough. The housing 14 includes a seal case 14A through which the rotary shaft 20 rotatably penetrates in a sealed state, a cylindrical case 14B connected to the seal case 14A and rotatably supporting the rotary shaft 20 by bearings 16A and 16B provided on an inner peripheral side, and a cover case 14C closing one end of the cylindrical case 14B. The seal case 14A, the cylindrical case 14B, and the cap case 14C are fixedly connected to each other. The lid case 14C is provided with a lid 14D for closing an opening through which the rotary shaft 20 can be inserted and removed.

The seal housing 14A is provided with seal portions 14Aa, 14Ab, and 14Ac and an intermediate atmospheric chamber 14Ad serving as an atmospheric pressure space (gap) for sealing the interior of the valve housing 10.

On the inner peripheral surface side of the cylindrical shell 14B, fluid path rings 17 and 18 are fixed at positions between the bearings 16A and 16B in the direction along the axis LL so as to slidably contact the outer peripheral surface 20B of the rotary shaft 20.

A pinion gear 21 is fixed to a central position between the fluid path rings 17 and 18 on the outer peripheral surface 20b of the rotary shaft 20, and the pinion gear 21 constitutes a rotary shaft drive mechanism 100 (see fig. 8) for driving (rotating) the rotary shaft 20. The pinion 21 is housed in an internal space 22h of the cylindrical case 14B which can be sealed from the outside, and a rack member 22 having a circular rod shape is connected to the pinion 21. In fig. 7B, the rack member 22 is reciprocated in the depth direction of the paper surface, whereby the rack member 22 rotates the rotary shaft 20 via the pinion 21.

[ rotating shaft drive mechanism 100]

Fig. 8 is a sectional view (extended position) showing the rotary shaft drive mechanism 100. Fig. 9 is a sectional view (retracted position) showing the rotary shaft drive mechanism 100. Fig. 10 is an enlarged sectional view of a main portion showing the rack member and the sliding bearing. Fig. 11 is an enlarged sectional view of a main portion showing an engagement portion of the rack member and the pinion.

The rotary shaft drive mechanism 100 for rotating the rotary shaft 20 includes a pinion gear 21 and a rack member 22, the pinion gear 21 being fixed to the rotary shaft 20, and the rack member 22a including rack teeth 22a meshing with the pinion gear 21.

The rotary shaft drive mechanism 100 includes a rotary drive cylinder 110 (rotary cylinder) for reciprocating the rack member 22 and an urging portion 120. The rack member 22 can linearly reciprocate along the axis (longitudinal direction) C by rotationally driving the cylinder 110 and the urging portion 120.

As shown in fig. 8 and 9, the rack member 22 is connected to a piston 112, and the piston 112 reciprocates with an axis in a direction orthogonal to the axis of the rotary shaft 20. The piston 112 is accommodated in a cylindrical cylinder body (housing) 111 to configure a rotary drive cylinder (drive mechanism, rotary cylinder, cylinder block) 110. The rack member 22 connected to the rotation driving cylinder 110 is expanded by supplying compressed air (driving gas) to an expansion pressure space (second pressure space) 113 located on the opposite side of the piston 112 from the rack member 22. Similarly, the rack member 22 is contracted by moving the piston 112 biased by the biasing portion 120.

The rack member 22 is housed in rack housing spaces (spaces) 22d, 22g, and 22m so as to be movable in the axial direction, and the housing spaces (spaces) 22d, 22g, and 22m are provided in the housing 14Bb integrated with the housing 14B so as to extend in a direction orthogonal to the rotation shaft 20. The spaces 22d, 22g, 22m have a diameter dimension larger than that of the rack member 22. Inside the spaces 22d, 22g, and 22m, the rack member 22 is supported to be able to reciprocate by slide bearings (bearings) 115B and 115C, and the slide bearings 115B and 115C are provided so as to cover the outer peripheries of two portions of the rack member 22.

The bearings 115B and 115C are disposed on both sides of the position where the pinion 21 and the rack member 22 mesh with each other in the axial direction of the rack member 22. Both the bearings 115B and 115C are integral with the housing 14Bb and have outer peripheral surfaces that are reduced in diameter so as to be smaller than the diameter of the space 22g, and the bearings 115B and 115C are in close contact with the outer peripheral surface of the rack member 22.

On one side of the outer peripheral surface of the rack member 22 in the circumferential direction, a plurality of rack teeth 22a that mesh with the pinion gear 21 are provided adjacent in the axial direction. A communication groove 116 is provided in a circumferential direction of the outer peripheral surface of the rack member 22 at a position different from the position where the rack teeth 22a are provided. The communication groove 116 communicates with the space 22d and the space 22g located on both sides of the bearing 115B with respect to the axial direction of the rack member 22.

As shown in fig. 10, the communication groove 116 communicates with the space 22g and the space 22m located on both sides of the bearing 115C with respect to the axial direction. The length of the communication groove 116 is set to maintain a communication state in the space 22d and the space 22g on both sides of the bearing 115B and a communication state in the space 22g and the space 22m on both sides of the bearing 115C even when the rack member 22 is reciprocated.

The expansion pressure space 113 is connected to a supply source through a sequential circuit SQ described later, and the supply source supplies compressed air for expansion from the outside of the rotation driving cylinder 110 through an expansion air port (supply passage) 114.

A supply passage 22j through which compressed air is supplied from a supply source from the outside of the rotation driving cylinder 110 is connected to the contracted pressure space (first pressure space) 22c through a sequential circuit SQ described later. The compressed air supplied from the supply passage 22j functions as damping air having a damping pressure at the time of contraction.

The supply passage (contraction vent) 22j is connected to the outside of the housing 14B via a space 22d in which the rack member 22 is housed, a communication groove 116 disposed at a position corresponding to the reduced diameter of the bearing 115B, a partial space corresponding to the rack teeth 22a, a space 22g having a larger diameter between the bearing 115B and the bearing 115C, and an internal space 22h of the housing 14B for housing the pinion gear 21, with respect to a path from the contraction pressure space 22C to the compressed air supply source.

A rotary shaft 20 supported by the housing 14 through bearings 16A, 16B is driven by a rack member 22 reciprocated by a rotary drive cylinder (rotary drive means), and is rotated together with a pinion 21 engaged with the rack member 22.

In addition, at the time of the contraction operation of the rotation driving cylinder (driving mechanism, rotation cylinder) 110 and while maintaining the contracted position Pb of the rack member 22, the pressurized state may be maintained in any of the contracted pressure space 22C, the housing space 22d, the space 22g housing the rack member 22, the communication groove 116 provided so as to correspond to the reduced diameter bearing 115B and the space 22g corresponding to the meshing position of the rack 22a, the spaces 22d, 22g, and 22m having the increased diameter regardless of the positions of the bearing 115B and the bearing 115C, the internal space 22h of the housing 14B housing the pinion 21, and the supply passage 22j connected to the internal space 22h and the outside of the housing 14B.

The rotation driving cylinder 110 reciprocates the rack member 22 by performing telescopic driving. The rotation driving cylinder 110 is integrated with the housing 14B for housing the rotation shaft 20. The rotation driving cylinder 110 includes a cylindrical cylinder body 111, an internal space 111b inside the cylinder body 111, and a piston 112 slidably accommodated in the internal space 111.

The rotary drive cylinder 110 is provided with an urging portion 120 in series in the axial direction at a position on the opposite side of the cylinder body 111 from the rack member 22. The biasing portion 120 is integrated with the cylinder body 111, and includes a spring member 120s, and the spring member 120s is disposed outside the cylindrical cylinder body 111 having the closed one end side 111 a. The spring member 120s is connected to the piston 112 and the shaft 122s and can transmit a force in the expansion and contraction direction to the piston 112.

An expansion pressure space 113 is formed in the internal space 111b of the rotation driving cylinder 110, the expansion pressure space 113 being defined by one end side 111a of the cylinder body 111 and one surface side 112a of the piston 112, and the capacity being changeable by the movement of the piston 112. Further, a stretching vent port (vent port) 114 is formed in the cylinder main body 111, and the stretching vent port 114 communicates with the stretching pressure space 113 and supplies compressed air for extension driving to the stretching pressure space 113 through a sequence circuit SQ described later. A pump, for example, may be connected to the vent port 114 as a driving pressure air supply source provided outside the gate valve 1.

The piston 112 is housed in the internal space 111b of the cylinder body 111 so as to be linearly reciprocable along an axis (longitudinal direction) C. The piston 112 having such a structure is slidable between an extended position Pa (fig. 8) and a retracted position (fig. 9). In the extension position Pa (fig. 8), the extension pressure space 113 is expanded to the maximum, and the piston 112 is located at the farthest position from the one end side 111a in the internal space 111b of the cylinder main body 111. In the contraction position Pb (fig. 9), the contraction pressure space 22c on the rack member 22 side of the piston 112 is expanded to the maximum, the expansion pressure space 113 is contracted to the minimum, and the piston 112 is located at the position closest to the one end side 111 a.

Note that, in fig. 9, illustration of the rack member 22 is omitted.

Further, a projection 112c is formed on one surface side 112a (first surface) of the piston 112. A recess 111c into which the projection 112c enters when the piston 112 is in the retracted position Pb is formed at one end side 111a of the cylinder main body 111. The outer diameter of the projection 112c is substantially equal to the inner diameter of the recess 111c, and the outer diameter of the projection 112c and the inner diameter of the recess 111c are set so that the inside of the recess 111c and the expansion pressure space 113 are in a nearly airtight state when the outer peripheral surface of the projection 112c and the inner surface of the recess 111c slide. One end side of the vent port 114 is formed at a position exposed by the concave portion 111 c.

A shaft 122s is fixed to the one surface side 112a of the piston 112 at the center position of the protrusion 112 c.

Further, the rack member 22 is fixed to the other surface side 112b (second surface) of the piston 112 by a projection (connecting portion) 112d formed in the same manner as the projection 112 c. The outer diameter of the connecting portion 112d is substantially equal to the inner diameter of the rack housing space 22d, and the outer diameter of the connecting portion 112d and the inner diameter of the rack housing space 22d are set so that the inside of the rack housing space 22d and the contracted pressure space 22c are in a nearly airtight state when the outer surface of the connecting portion 12d and the inner surface of the rack housing space 22d slide. One end side of the supply passage (the contraction ventilation port) 22j may be formed at a position exposed from the rack housing space 22 d.

A buffer groove (buffer mechanism) 118 is formed in the projection 112C of the piston 112, the sectional area of the buffer groove 118 continuously changes along the axis (longitudinal direction) C, which is the reciprocating direction of the piston 112, and the buffer groove 118 gradually introduces the air in the extension pressure space 113 toward the vent port 114.

Specifically, the buffer groove 118 is formed in the protrusion 112C of the piston 112, and is configured by a groove inclined with respect to the axis (longitudinal direction) C so that the cross-sectional area thereof is expanded from the one surface side 112a of the piston 112 toward the one end side 111a of the cylinder body 111.

A buffer groove (extension buffer groove) 119 is formed in the projection 112d of the piston 112, the sectional area of the buffer groove 119 continuously changes along the axis (longitudinal direction) C which is the reciprocating direction of the piston 112, and the buffer groove 119 gradually introduces the air in the contraction pressure space 22C toward the space 22 g.

The buffer groove (extension buffer groove) 119 is formed in the protrusion 112d of the piston 112 in the same manner as the buffer groove 118, and is configured by a groove inclined with respect to the axis (longitudinal direction) C so that the sectional area thereof is expanded from the other surface side 112b of the piston 112 toward the space 22d on the rack member 22 side.

The rotation driving cylinder 110 has an internal space 111b of the cylinder body 111 communicating with the outside of the one end side 111a of the cylinder body 111 via a shaft hole 111s, and the shaft hole 111s penetrates through a radially central position in the extending/retracting axis direction of the piston 112. Inside the shaft hole 111s, the shaft 122s can be reciprocated. Thereby, the cylinder 110 and the biasing portion 120 are interlocked.

The cylindrical side surfaces of the piston 112 and the internal space 111b, and the inner surfaces of the shaft 122s and the shaft hole 111s are sealed by sealing members such as O-rings over the entire circumference so as to be slidable with respect to each other while maintaining a sealed state.

A fixing portion 122 having a larger diameter is provided at an end of the shaft 122s on the side opposite to the piston 112. A spring member 120s is attached between the outer side of the one end side 111a of the cylinder main body 111 and the other surface 122b of the fixed portion 122, and the spring member 120s can exert a biasing force by expanding and contracting.

As shown in fig. 8, 9, and 10, the rack member 22 is formed in a circular rod shape in a cross section perpendicular to the axis (longitudinal direction) C. Rack teeth 22a are formed on a part of the circumferential surface of the round bar-shaped rack member 22 in an array at a predetermined pitch along the axis (longitudinal direction) C.

Sliding bearings 115B and 115C that slidably support the rack member 22 are disposed on both sides of the meshing portion S between the pinion gear 21 and the rack teeth 22a fixed to the rotary shaft 20. As shown in fig. 10, the sliding bearings 115B and 115C are formed with an inner peripheral surface 115a having a circular cross section slightly larger than the cross section of the rack member 22. The outer periphery of the rack member 22 is in contact with the inner peripheral surface 115a, and the inner peripheral surface 115a smoothly and slidably supports the circular rod-shaped rack member 22 along the axis (longitudinal direction) C.

As shown in fig. 8 and 10, the communication groove (groove) 116 is formed on the surface (circumferential surface) of the rack member 22 so as to extend in the axis C direction to both outer position sides of the sliding bearing 115B and the sliding bearing 115C. A boss (not shown) that enters the communication groove 116 is formed in the housing 14B that houses the rack member 22. The rack member 22 can be prevented from rotating about the axis C by the engagement of the communication groove 116 and the boss. Thus, the rack member 22 does not twist about the axis C when reciprocating.

Fig. 11 is an explanatory diagram showing the arrangement positions of the slide bearings 115B and 115C.

The sliding bearings 115B and 115C are preferably disposed in a direction farther from the meshing portion S of the rack member 22 than intersection points P1 and P2 of action lines (extension lines) L1 and L2 of the rack member 22 and an axial center (shaft center line) C of the rack member 22, which are generated in the meshing portion S of the pinion gear 21 and the rack teeth 22 a.

That is, when points at which lines of action L1, L2, which are the moving directions of contact points between the pinion 21 and the rack teeth 22a, which are two meshing teeth, intersect with the axial center (shaft center line) C of the rack member 22 are defined as intersection points P1, P2, the slide bearings 115B, 115C are disposed such that the center lines Q of the slide bearings 115B, 115C are located further outward than the intersection points P1, P2.

By setting the arrangement positions of the sliding bearings 115B and 115C as described above, the sliding bearings 115B and 115C do not receive an external force generated by the rotation of the pinion gear 21, that is, a force in a direction away from the pinion gear 21. This prevents stress in the direction orthogonal to the axial center (shaft center line) C from being applied to the contact portions of the sliding bearings 115B and 115C and the rack member 22, and reduces the frictional force between the sliding bearings 115B and 115C and the rack member 22, thereby enabling the sliding bearings 115B and 115C to smoothly slidably hold the rack member 22.

A contact type limit switch valve (rotation operation end detection switch valve) cdS may be provided on the one end side 111a of the cylinder main body 111, and the contact type limit switch valve cdS may be operated when the piston 112 is in the retracted position Pb. The limit switch valve cdS may be configured such that, for example, in the sequence circuit SQ leading to the output point FR, the operation of supplying compressed air to the closure release cylinder 80 can be performed at the end position of the piston 112 depending on the limit switch valve cdS.

Fig. 9 shows a state immediately before reaching the retracted position Pb for the purpose of explaining an air cushion operation by the buffer tank 118 and the like described later. Therefore, the operation state of the limit switch valve cdS is not shown.

According to the rotary shaft drive mechanism 100 configured as described above, for example, when the piston 112 is in the retracted position shown in fig. 9, the rotary shaft 20 interlocked (rotated) from the rack member 22 fixed to the piston 112 via the pinion gear 21 is set to a state rotated to the head in the counterclockwise direction in fig. 8 within the rotation range of the rotary shaft 20. At the position of the rotary shaft 20, the movable valve portion 40 is located at the valve closing position E2 (fig. 1) of the flow path H by the neutral valve portion 30 fixed to the rotary shaft 20.

On the other hand, when the piston 112 is moved from the contracted position Pb to the expanded position Pa shown in fig. 8, compressed driving air is fed from the air port 114 into an expanded pressure space 113 defined by the inner surface of the cylinder main body 111 and the one surface side 112a of the piston 112.

Then, the internal pressure of the expansion pressure space 113 rises, the force generated by the internal pressure becomes larger than the urging force of the spring member 120s, the piston 112 moves (slides) in the direction away from the one end side 111a of the cylinder main body 111 along the axis (longitudinal direction) C, and the expansion pressure space 113 expands.

At this time, the excess air inside the contracted pressure space 22c is discharged from the contracted pressure space 22c to the outside through the space 22d for housing the rack member 22, the communication groove 116 disposed at the position corresponding to the bearing 115B, and the partial space corresponding to the rack teeth 22a, the internal space 22g of the housing 14Bb, the internal space 22h of the housing 14B, and the vent 22j, in addition to the damping air. Further, when the movable valve portion 40 approaches the retracted position E1, the air in the contracted pressure space 22c is gradually discharged toward the space 22g through the buffer groove (extension buffer groove) 119 and the control buffer flow passage 119a, and an air damping effect (air cushion effect) can be obtained.

At this time, in the biasing portion 120, the piston 112 connected to the shaft 122s is biased by the spring member 120s from the extended position Pa shown in fig. 8 toward the retracted position Pb shown in fig. 9, and the movable valve portion 40 can be normally closed at the valve closing position E2 (fig. 1).

In a case where the piston 112 is moved to the extended position Pa in a direction away from the one end side 111a of the cylinder main body 111, the rack member 22 fixed to the piston 112 rotates the pinion 21 engaged with the rack teeth 22a in the clockwise direction in fig. 8. Thereby, the rotary shaft 20 also rotates clockwise, and the movable valve portion 40 is moved to the retreat position E1 (fig. 1) of the flow path H in a pendulum motion by the neutral valve portion fixed to the rotary shaft 20.

Further, when the piston 112 is located at the extension position Pa shown in fig. 8 and the movable valve portion 40 is located at the retreat position (E1) of the flow passage H, when the piston 112 moves from the extension position Pa (fig. 8) to the contraction position Pb (fig. 9), an air cushion effect is generated by the residual pressure in the extension pressure space 113.

The piston 112 connected to the shaft 122s is moved (slid) in a direction approaching the one end side 111a of the cylinder main body 111 along the axis (longitudinal direction) C by the urging force of the spring member 120s, and the pressure space 113 is contracted.

At this time, although the excess air inside the extension pressure space 113 is discharged from the extension pressure space 113 to the outside through the vent 114, when the piston 112 approaches the valve closing position E2, the air inside the extension pressure space 113 is discharged to the outside through the buffer groove 118. This smoothly changes the movement of the piston 112 to the retracted position Pb.

As a result, when the piston 112 connected to the shaft 122s moves from the extended position Pa shown in fig. 8 to the contracted position Pb shown in fig. 9 as described later, the biasing portion 120 can prevent the inner surface of the cylinder main body 111 from coming into hard contact with and impacting the piston 112 during the closing operation to the valve closing position E2 (fig. 1).

The compressed air is supplied from the air port 22j to the contraction pressure space 22c via the internal space 22h in which the pinion 21 is housed, the internal space 22g in which the rack 22 is housed, the communication groove 116 disposed at a position corresponding to the bearing 115B, the space 22g corresponding to the meshing position of the rack teeth 22a, and the housing space 22 d. At this time, since the compressed air is sealed in a state of being nearly closed by the control pin 119C that controls the cushion flow path 119a, the inside of the communication groove 116 and the space 22d corresponding to the bearing 115C become a pressurized state in which the pressure is lower than the pressure of the contracted pressure space 22C.

In a case where the piston 112 is moved to the contracted position Pb toward the one end side 111a of the cylinder main body 111, the rack member 22 fixed to the piston 112 rotates the pinion 21 engaged with the rack teeth 22a in the counterclockwise direction in fig. 8. Thereby, the rotary shaft 20 also rotates counterclockwise, and the movable valve portion 40 is moved to the valve closing position E2 (fig. 1) of the flow passage H in a pendulum motion by the neutral valve portion 30 fixed to the rotary shaft 20.

In this manner, the internal pressures of the extension pressure space 113 and the contraction pressure space 22c in the cylinder body 111 configuring the rotary shaft drive mechanism 100 are changed, and the piston 112 is linearly moved between the extension position Pa (fig. 8) and the contraction position Pb (fig. 9) by the urging force of the spring member 120 s. Thus, the rotary shaft 20 can be rotated by the rack member 22 and the pinion 21, and the movable valve portion 40 can be moved between the retracted position E1 and the valve-closing position E2 (fig. 1) with respect to the flow path H.

The biasing portion 120 can normally close the valve closing position E2 (fig. 1).

When the piston 112 moves between the extended position Pa and the retracted position Pb as described above, the movement of the piston 112 to the retracted position Pb is smoothly changed by the buffer groove 118. Similarly, the movement of piston 112 to extended position Pa can be smoothly changed by buffer groove 119.

The buffer tank 118 will be explained.

When the piston 112 is moved from the expansion position Pa to the contraction position Pb, the movement of the piston 112 to the contraction position Pb is smoothly changed by the buffer groove 118 formed in the projection 112c of the piston 112 so as to avoid a sudden stop of the piston 112 due to a sudden reduction of the expansion pressure space 113, that is, a sudden and large stress applied to the meshing portion S of the rack member 22 and the pinion 21.

For example, a case will be described in which compressed air for driving is supplied to the contracted pressure space 22c, the internal pressure of the contracted pressure space 22c is set to a damping pressure state, and the piston 112 is moved toward the contracted position Pb by the urging force of the spring member 120 s. In this case, if the piston 112 moves to a position where the protrusion 112c enters into the recess 111c of the cylinder body 111, the flow of air that flows into the recess 111c from the extension pressure space 113 around the protrusion 112c and is discharged from the vent 114 is blocked. As a result, the internal pressure of the expansion pressure space 113 expanded at the peripheral edge of the projection 112c suddenly increases (the expansion pressure space 113 is compressed), and the force acts in a direction in which the moving speed of the piston 112 suddenly decreases.

However, the air in the expansion pressure space 113 is guided to the vent 114 through the buffer groove 118 formed in the protrusion 112 c. That is, the extension plenum 113 is communicated to the vent 114 through the buffer reservoir 118.

Further, since the buffer groove 18 is formed so as to expand in cross-sectional area from the one surface side 112a of the piston 112 toward the one end side 111a of the housing 111, the cross-sectional area, i.e., the opening area, of the buffer groove 118 decreases as the piston 112 approaches the retracted position Pb (fig. 9). Thus, immediately before the piston 112 reaches the contraction position Pb, the flow rate of air from the expansion pressure space 113 to the vent 114 gradually decreases (decreases), and therefore the internal pressure of the expansion pressure space 113 gradually decreases. This can slowly stop the piston 112 at the retracted position Pb. Therefore, sudden stop of the piston 112 due to sudden reduction of the expansion pressure space 113 can be prevented, and smooth stop can be achieved without sudden application of a large stress to the meshing portion S (fig. 11) of the rack member 22 and the pinion gear 21.

Similarly, the movement of piston 112 to the extended position Pa is smoothly changed by buffer tank 119 by feeding compressed driving air as damping air in advance to be in a damping pressure state. Next, a description will be given of a case where compressed driving air is supplied to the extension pressure space 113, and the internal pressure of the extension pressure space 113 is increased to move the piston 112 toward the extension position Pa. In this case, if the piston 112 moves to a position where the projection 112d enters the space 22d of the housing 14Bb, the flow of air that flows into the space 22d from the contracted pressure space 22c around the projection 112d, moves to the space 22h side, and is discharged from the vent 22j is blocked. As a result, the internal pressure of the contracted pressure space 22c expanding around the projection 112d suddenly increases (the contracted pressure space 22c is compressed), and the force acts in a direction in which the moving speed of the piston 112 suddenly decreases.

However, the air in the contraction pressure space 22c is guided to the space 22d communicating with the vent 22j through the buffer groove 119 by the buffer groove 119 formed in the protrusion 112 d.

That is, the contraction pressure space 22c communicates with the space 22d through the buffer tank 119.

Further, since the buffer groove 119 is formed so as to expand in cross-sectional area from the one surface side 112b of the piston 112 toward the other end side 14Ba of the housing 14Bb, the cross-sectional area of the buffer groove 119, i.e., the opening area, decreases as the piston 112 approaches the extension position Pa (fig. 8). Thus, immediately before the piston 112 reaches the extension position Pa, the flow rate of the air from the contracted pressure space 22c to the space 22d gradually decreases (decreases), and therefore the decrease in the internal pressure of the contracted pressure space 22c in the damping pressure state gradually decreases. This can slowly stop the piston 112 at the extension position Pa. Therefore, sudden stop of the piston 112 due to sudden reduction of the contracted pressure space 22c can be prevented, and smooth stop can be achieved without sudden application of a large stress to the meshing portion S (fig. 11) of the rack member 22 and the pinion 21.

In the rotation driving cylinder 110, in addition to the buffer grooves 118, 119 described above, a control buffer flow passage 119a is provided for adjusting the moving speed of the piston 112 immediately before the piston 112 reaches the extension position Pa or immediately after the piston 112 starts moving from the extension position Pa.

When the piston 112 is in the extension position Pa (fig. 8), one end of the control damper flow path 119a opens into the space 22d at a position blocked by the projection 112 d. The other end of the control buffer flow path 119a is a flow path 119a opening to the other surface side 14Ba of the case 14 Bb.

The flow path 119a is provided with a control hole 119 b. The control hole 119b extends in a direction intersecting the flow passage 119a and communicates with the flow passage 119a, and the control hole 119b opens to the outside of the housing 14 Bb. A control pin 119c capable of closing the flow path 119a is provided in the control hole 119b so as to be slidable in the direction in which the control hole 119b extends.

The control buffer flow path 119a is used to control the flow rate of air moving between the contracted pressure space 22c and the space 22d, similarly to the buffer groove 119.

Specifically, in the pilot cushion flow path 119a, when the control pin 119c moves inside the pilot hole 119b, the sectional area of the flow path 119a changes according to the position of the control pin 119 c. Thereby, the flow rate of the air moving between the contracted pressure space 22c and the space 22d is changed. Therefore, when the damper flow passage 119a is controlled to be opened to the space 22d and the protrusion 112d is controlled to enter the space 22d of the housing 14Bb, the movement speed of the piston 112 can be controlled by adjusting the opening degree of the flow passage 119a by controlling the position of the pin 119 c.

If the control pin 119c is pulled out to increase the sectional area of the flow passage 119a, the moving speed of the rack member 22, that is, the moving speed of the pendulum movement of the movable valve body 40 (movable valve portion) increases. Further, if the control pin 119c is inserted so that the sectional area of the flow passage 119a is reduced, the moving speed of the rack member 22, that is, the moving speed of the pendulum movement of the movable valve body 40 is reduced.

In particular, such an air damping effect is obtained not only immediately before the piston 112 reaches the extended position Pa but also when the piston 112 starts moving from the extended position Pa to the retracted position Pb, that is, when the movable valve portion 40 starts moving to the retracted position E1 (fig. 1) of the flow passage H by the pendulum motion. This allows smooth start and stop operations without applying a large stress to the meshing portion S (fig. 11) of the rack member 22 and the pinion 21.

In the case of such a cylinder 110, the supply of compressed air is switched between the expansion port 114 and the contraction port 22j, and the cylinder 110 can be expanded and contracted to perform the swing operation of the neutral valve body 5.

The fluid path ring 17 and the fluid path ring 18 have an inner diameter almost equal to the rotation shaft 20. The outer diameter of the fluid path ring 17 located closer to the valve housing 10 than the pinion 21 is set to be larger than the outer diameter of the bearing 16A and smaller than the outer diameter dimension of the pinion 21. The outer diameter of the fluid path ring 18 located closer to the cover 14D than the pinion 21 is set larger than the diameter size of the pinion 21. If the rotary shaft 20 supported by the bearings 16A, 16B rotates, the contact position changes in the circumferential direction for the fluid path ring 17 and the fluid path ring 18.

A radial ring path 17c is provided in the fluid path ring 17. The radial annular path 17c is a fluid path of a part of the supply passage 41 for supplying the driving gas to the annular cylinder 80 formed between the movable valve plate portion 50 and the movable valve frame portion 60 in the second peripheral region 40 a. The radial ring path 17c extends in the radial direction of the fluid path ring 17, and opens on the outer circumferential surface 17a and the inner circumferential surface 17b of the fluid path ring 17. The radial ring path 17c communicates with a path 14Bc penetrating in the radial direction of the cylindrical shell 14B on the outer peripheral surface 17a of the fluid path ring 17.

A radial ring path 18c is provided in the fluid path ring 18. The radial annular path 18c is connected to an intermediate atmospheric chamber 55 (see fig. 5). The intermediate atmospheric chamber 55 is provided on the gas supply side by the second-layer seals 51a and 52a in the double-layer seal provided in the annular cylinder 80 formed between the movable valve portion 50 and the movable valve frame portion 60 in the second peripheral region 40 a. The radial path ring 18c is a fluid path of a part of the communication passage 42 for allowing the driving gas to escape to the outside of the gate valve 1 when the first-layer seal portions 51b and 52b are broken. The radial ring path 18c extends in the radial direction of the fluid path ring 18, and opens on the outer circumferential surface 18a and the inner circumferential surface 18b of the fluid path ring 18. The radial ring path 18c communicates with a path 14Cc passing through the cylindrical case 14B in the radial direction on the outer peripheral surface 18a of the fluid path ring 18.

A groove 17d is annularly provided on an inner peripheral surface 17b of the fluid path ring 17, and the groove 17d is surrounded by an outer peripheral surface 20b of the rotary shaft 20 to form a circumferential path.

A radial shaft inner path 27 is opened in the outer peripheral surface 20b of the rotary shaft 20 at a position facing the groove 17d, and the radial shaft inner path 27 communicates with an axial shaft inner path 25 extending in the LL direction along the axis of the rotary shaft 20 and opened in one end surface 20a of the rotary shaft 20.

A groove 18d is provided around the inner peripheral surface 18b of the fluid path ring 18, and the groove 18d is surrounded by the outer peripheral surface 20b of the rotary shaft 20 to form a circumferential path.

A radial shaft inner path 28 is opened in the outer peripheral surface 20b of the rotary shaft 20 at a position facing the groove 18d, and the radial shaft inner path 28 communicates with an axial shaft inner path 26 extending in the LL direction along the axis of the rotary shaft 20 and opened in one end surface 20a of the rotary shaft 20.

These axial in-shaft path 25 and axial in-shaft path 26 are in a parallel state to each other and to the axis LL. The other end 20c of the rotary shaft 20 facing the cover 14D is blocked.

Both the axial in-shaft path 25 and the axial in-shaft path 26 communicate with the supply path 41 and the communication path 42 inside the neutral valve portion 30.

Sealing members 17h, 17j, and 17k such as O-rings are fitted around the fluid passage ring 17, and the sealing members 17h, 17j, and 17k slidably seal the opening portion of the radial inner passage 27 and the groove 17d between the inner circumferential surface 17b and the outer circumferential surface 20b of the rotary shaft 20.

Sealing members 17e, 17f, and 17g such as O-rings are provided around the fluid path ring 17, and the sealing members 17e, 17f, and 17g seal the opening portion of the radial annular path 17c and the path 14Bc between the outer peripheral surface 17a and the inner surface of the cylindrical shell 14B.

Sealing members 18h, 18j, 18k such as O-rings are fitted around the fluid passage ring 18, and the sealing members 18h, 18j, 18k slidably seal the opening portion of the radial inner passage 27 and the groove 18d between the inner circumferential surface 18b and the outer circumferential surface 20b of the rotary shaft 20.

Sealing members 18e, 18f, 18g such as O-rings are fitted around the fluid passage ring 18, and the sealing members 18e, 18f, 18g seal the opening portion of the radial annular passage 18c and the passage 14Cc between the outer peripheral surface 18a and the inner surface of the cylindrical shell 14B.

The fluid path ring 17 and the fluid path ring 18 having such a configuration can maintain the state in which the radial shaft inner path 27 and the radial shaft inner path 28 communicate with each other regardless of the rotational position of the rotary shaft 20, and thus supply of the driving fluid with excellent sealing performance can be performed as described later. Further, since the supply passage 41 and the communication passage 42 are independently connected to each other, a dual system having different pressure states or different gas states can be controlled without affecting the inside of the valve housing 10 regardless of the rotational position of the rotary shaft 20.

Meanwhile, since the grooves 17d, 18d as the circumferential paths are provided around the fluid path ring 17 and the fluid path ring 18, the pressure generated by the fluid in the grooves 17d, 18d acts around the outer peripheral surface 20b of the rotary shaft 20. Therefore, the pressure acting in the radial direction can be made uniform over the entire circumference, and therefore, the support state of the rotary shaft 20 by the bearings 16A and 16B can be prevented from being affected regardless of the pressure state in these flow passages.

Meanwhile, the fluid path ring 17 and the fluid path ring 18 are provided between the bearing 16A and the bearing 16B, so that the distance between the bearing 16A and the bearing 16B supporting the rotation shaft can be ensured to be as long as possible. Accordingly, when the moment acting on the rotary shaft in the direction of tilting the rotary shaft 20 is held by the bearing 16A and the bearing 16B, the radial load applied to the bearing 16A and the bearing 16B can be minimized, and the durability of the bearing 16A and the bearing 16B can be improved. Alternatively, the axial length of the rotary shaft 20 can be secured while maintaining the necessary deformation preventing capability in the inclined direction of the rotary shaft 20, and the rotary drive cylinder 110 including the rotary shaft 20 can be downsized, thereby downsizing the valve.

Further, by adopting the above-described configuration as the outer diameter dimensions of the bearing 16A and the bearing 16B, the fluid path ring 17, the pinion gear 21, and the fluid path ring 18, it is possible to assemble the rotating mechanism portion to the housing 14 by inverting the mounting surface of the rotating mechanism portion with respect to the valve housing only by changing the assembly direction of the components without changing the configuration of the components.

In the present embodiment, the compressed air for driving the cylinder 80 can be supplied to the neutral valve body 5 through the inside of the rotary shaft 20 without exposing (exposing) the compressed air to the hollow portion 11 inside the valve housing 10, and the communication passage 42 leading to the intermediate atmospheric chambers 55 and 56 described later can be made to communicate with the outside of the valve housing 10 through the inside of the rotary shaft 20.

Axial in-shaft paths 25 and 26 as a supply path 41 and a communication path 42 are provided in parallel with the rotary shaft 20. The fluid path ring 17 and the fluid path ring 18 corresponding to the supply passage 41 and the communication passage 42 are provided at different positions in the direction along the axis LL of the rotary shaft 20. With this configuration, the plurality of paths 25 and 26 can be simultaneously brought into independent communication states via the inside of one rotary shaft 20. Therefore, the supply passage 41 for the driving fluid of the cylinder 80 and the communication passage 42 for the intermediate atmosphere for safety can be formed by only one rotary shaft 20, and the supply passage 41 and the communication passage 42 can be arranged on the rotary shaft 20 without using another structure.

In the inner peripheral surface 17b of the fluid passage ring 17, a groove 17d communicating with the radial ring passage 17c is provided between the seal member 17h and the seal member 17j, and a groove 17p is annularly provided between the seal member 17j and the seal member 17 k.

The groove 17p forms a second intermediate atmospheric chamber as an atmospheric pressure space (gap) with the outer peripheral surface 20b of the rotating shaft 20 facing thereto, and is connected to the outside of the housing via a second communication passage 42A.

These seal members 17j and 17k function as a double-layer seal portion for the groove 17d, and the groove 17d is a supply passage 41 in which the driving gas is present. With this configuration, even if the seal member 17, which is the first seal, of the rotary shaft 20 is broken during pressurization of the cylinder 80, compressed air (driving gas) is released to the outside of the housing 14 through the groove 17p and the second communication passage 42A. Therefore, the following structure can be obtained: this structure prevents a problem that the pressure state changes between the groove 17d and the internal space 22h, such as the compressed air is discharged from the groove 17d of the fluid path ring 17 to the internal space 22h of the pinion gear 21 in the housing 14B.

At the same time, the seal member 17k and the seal member 17j function as a double-layer seal portion of an internal space 22h serving as a pressurized space in a cylinder (driving mechanism, rotary cylinder) driven by the rotation of the rotary shaft 20. With this configuration, even if the seal member 17k, which is the first seal, of the rotary shaft 20 is broken during contraction of the rotation driving cylinder, compressed air (driving gas) is released to the outside of the housing 14 through the groove 17p and the second communication passage 42A. Therefore, the following structure can be obtained: this structure prevents a problem that the pressure state changes between the groove 17d and the internal space 22h, such as the compressed air is discharged from the internal space 22h to the groove 17d serving as the supply path 41 in the housing 14B.

Although the groove 17d and the internal space 22h are both pressurized spaces, when the pressure state corresponding to a predetermined operation is changed by breaking the seal portion, an unexpected operation such as sudden expansion of the thickness of the neutral valve element 5 or a rotational operation of the neutral valve element 5 is prevented.

That is, the seal member 17k, the seal member 17j, the groove 17p, and the second communication passage 42A prevent the gate valve 1 from being damaged by seal breakage or the like.

In the inner peripheral surface 18b of the fluid passage ring 18, a groove 18d communicating with the radial ring passage 18c is provided between the seal member 18k and the seal member 18j, and a groove 18p is annularly provided between the seal member 18j and the seal member 18 h.

The groove 18p and the outer peripheral surface 20b of the opposite rotary shaft 20 form a second intermediate atmospheric chamber as an atmospheric pressure space (gap), and are connected to the outside of the housing through a second communication passage 42A.

These seal members 18j and 18h function as a double-layer seal portion for an internal space 22h serving as a pressurized space in a rotation driving cylinder (driving mechanism, rotation cylinder) of the rotation shaft 20. With this configuration, even if the seal member 18h as the first seal in the rotary shaft 20 is broken during contraction of the rotation driving cylinder, compressed air (driving gas) is released to the outside of the housing 14 through the groove 18p and the second communication passage 42A. Therefore, the following structure can be obtained: this structure prevents a problem that the pressure state changes between the groove 18d and the internal space 22h, such as compressed air being discharged from the internal space 22h side to the groove 18d as the communication passage 42 in the housing 14B.

Accordingly, when the internal space 22h is a pressurized space and the pressure state corresponding to a predetermined operation is changed by breaking the seal portion, an unexpected operation such as a rotation operation of the neutral valve body 5 is prevented from being caused.

That is, the seal member 18h, the seal member 18j, the groove 18p, and the second communication passage 42A prevent the gate valve 1 from being damaged by seal breakage.

A leakage flow path 14He extending in the radial direction is provided in the cylindrical shell 14B at a position close to the seal shell 14A. As shown in fig. 7B, the leak flow path 14He communicates with the leak space 22 He. The leak space 22He is formed at a position closer to the seal housing 14A than the bearing 16A, and is in contact with the surface 20b of the rotary shaft 20.

An axial leakage flow passage 27He is provided inside the rotary shaft 20 in contact with the leakage space 22 He. One end of the axial leak flow path 27He opens to the leak space 22 He. As will be described later, the other end of the axial leak flow path 27He penetrates the center of the rotary shaft 20 in the axial direction and opens into a through hole 21A, and a screw (fastening tool) 21d for fastening the rotary shaft 20 and the neutral valve portion 30 via a connection member 91 penetrates through the through hole 21A.

As shown in fig. 12A and 12B, the through hole 21A communicates with the opening 98 of the connecting member 91 and the space 31He provided in the neutral valve portion 30 and having the female screw (fastening tool) 31 to be screwed into the screw 21 d.

As will be described later, the screw 21d penetrates the opening 98 having no thread groove up to the space 31He having the fastened female thread 31. The space 31He is closed by a closing member not shown at a position close to the groove 95B.

In the air retention space 31He of the neutral valve portion 30, a helium leak test must be performed at a portion near the groove 95B located at the distal end of the space 31He to investigate whether or not the sealing by an unillustrated O-ring or the like is broken. Therefore, the air retention space 31He communicates with the leak space 22He via the opening 98, the through hole 21A, the axial leak flow path 27He, the leak space 22He, and the leak flow path 14He, and helium can be supplied through this portion in order to inspect the helium leak test in a sealed state for the air retention space 31He, the opening 98, and the through hole 21A.

By providing the axial leak flow path 27He and the leak flow path 14He in this manner, the helium leak test can be performed on the air retention space 31He, the opening 98, and the through hole 21A.

At the same time, the seal portions 14Aa, 14Ab, and 14Ac as the seal means along the surface 20b of the rotary shaft 20 and the intermediate atmospheric chamber 14Ad as the atmospheric pressure space (gap) can be subjected to a seal test into the hollow portion 11 from the leak flow path 14 He. That is, the helium leak test can be performed by supplying helium from the leak flow path 14He to the leak space 22He side to check the leak to the hollow portion 11.

Further, when the seal by the seal members 17h, 17j, and 17k, the seal members 17e, 17f, and 17g, and the like is broken and the compressed air leaks from the internal space 22h, the radial annular passage 17c, the groove 17d, and the like, which are pressurized spaces, to the leak space 22He, the leak flow path 14He can release the compressed air to the outside. This prevents the sealing portions 14Aa, 14Ab, and 14Ac from being pressurized, and prevents the leaked compressed air from flowing into the hollow portion 11.

[ neutral valve section 30 and connecting member 91]

Fig. 12A is an enlarged view of a main portion showing a fitting portion of the rotary shaft and the neutral valve body, and is a cross-sectional view taken along a radial direction of the rotary shaft. Fig. 12B is an enlarged view of a main portion showing a fitting portion of the rotary shaft and the neutral valve body, and is a sectional view taken along the axial direction of the rotary shaft.

The neutral valve portion 30 extends in a direction orthogonal to the axis of the rotary shaft 20, and has a surface parallel to the orthogonal direction. As shown in fig. 1, the neutral valve portion 30 includes a circular portion 30a overlapping the movable valve portion 40 and a rotating portion 30b that rotates the circular portion with rotation of the rotating shaft 20. The rotating portion 30b is located between the rotating shaft 20 and the circular portion 30a, and the width of the rotating portion 30b gradually increases from the rotating shaft 20 toward the circular portion 30 a. The rotary shaft 20 and the neutral valve portion 30 are provided so as to rotate relative to the valve housing 10 but not to move in the direction of the flow path H.

As shown in fig. 12B, a recess 95 into which the projection 93 of the connecting member 91 is fitted is formed at one end of the neutral valve portion 30. The cross-sectional shape of the recess 95 is substantially T-shaped in accordance with the cross-sectional shape of the connection member 91. As such recesses 95, recesses 95A, 95B are formed on both sides of the one surface side 30A and the other surface side 30B in the flow path direction H of the neutral valve portion 30, respectively.

Thus, the rotary shaft 20 can be selectively connected to the neutral valve portion 30 on either the upper side or the lower side in the flow path direction H.

Alternatively, the entire neutral valve body 5 may be attached to either one of the two surfaces of the rotary shaft 20. That is, if the neutral valve body 5 is attached to the recess 95A of the connecting member 91, the movable valve portion 40 blocks the first opening portion 12a when the gate valve 1 is closed. In contrast, if the neutral valve body 5 is attached to the recess 95B of the connection member 91, the movable valve portion 40 closes the second opening portion 12B.

As shown in fig. 12A and 12B, the projection 93 formed in the connecting member 91 and the recess 95 formed in the neutral valve portion 30 are fitted to each other. As shown in fig. 12A, the connection member 91 and the neutral valve portion 30 are in contact with each other in the fitted state by a set of first parallel surfaces 96a, 96b that extend parallel to each other in the flow path direction H and are spaced apart at a first interval t1, and a set of second parallel surfaces 97a, 97b that extend parallel to each other in the flow path direction H and are spaced apart at a second interval t2 that is wider than the first interval t 1.

The first parallel surfaces 96a and 96b and the second parallel surfaces 97a and 97b are arranged symmetrically with respect to an axis L extending perpendicular to the flow path direction H. The first parallel surfaces 96a and 96b and the second parallel surfaces 97a and 97b are disposed along the axis L so as not to overlap each other.

As shown in fig. 12A and 12B, first contact surfaces 93a and 93B constituting the set of first parallel surfaces 96a and 96B and second contact surfaces 93c and 93d constituting the set of second parallel surfaces 97a and 97B are formed on the protruding portion 93 of the connection member 91. The first contact surfaces 93a and 93b and the second contact surfaces 93c and 93d are connected by first inclined surfaces 93e and 93f, respectively. The projection 93 has a projection shape having a two-step width as a whole.

As shown in fig. 12A and 12B, third contact surfaces 95a and 95B that form a set of first parallel surfaces 96a and 96B and fourth contact surfaces 95c and 95d that form a set of second parallel surfaces 97a and 97B are formed in a recess 95 formed at one end of the neutral valve portion 30. The third contact surfaces 95a and 95b and the fourth contact surfaces 95c and 95d are connected by second inclined surfaces 95e and 95f, respectively. The recess 95 has a groove shape having a secondary width as a whole.

As shown in fig. 12A and 12B, a through hole 21A is formed in the center of the rotary shaft 20, and a screw (fastening member) 21 for fastening the rotary shaft 20 and the neutral valve portion 30 via a connection member 91 is inserted through the through hole 21A. Further, female threads 31 to be screwed with screws (fasteners) 21 are formed in a recess 95 formed at one end of the neutral valve portion 30. Further, the connecting member 91 is formed with an opening 98 which does not have a screw groove and through which the screw (fastener) 21 passes.

According to the above configuration, the projection 93 formed in the connecting member 91 is fitted in the recess 95 formed in the neutral valve portion 30, the screw 21 passes through the through hole 21A and the opening 98 from the upper end side of the rotary shaft 20, and the tip of the screw 21 is screwed into the female screw 31 of the neutral valve portion 30. Thereby, the rotary shaft 20 and the neutral valve portion 30 are fastened (fixed) by the connecting member 91.

In maintenance of the neutral valve portion 30, for example, in the process of replacing the repeatedly opened and closed neutral valve portion 30, when the neutral valve portion 30 is attached to the connecting member 91 fixed to the rotary shaft 20, the recess 95 formed at one end of the neutral valve portion 30 is opposed to the projection 93 formed on the connecting member 91.

Next, when the recess 95 of the neutral valve portion 30 is inserted into the projection 93, the third contact surfaces 95a and 95b of the recess 95 come into contact with the first contact surfaces 93a and 93b of the projection 93, respectively. The fourth contact surfaces 95c and 95d of the recess 95 are in contact with the second contact surfaces 93c and 93d of the protrusion 93, respectively.

In this insertion process, the contact surfaces between the recess 95 and the projection 93 are limited to the first parallel surfaces 96a and 96b and the second parallel surfaces 97a and 97b, and the first inclined surfaces 93e and 93f of the projection 93 and the second inclined surfaces 95e and 95f of the recess 95 do not contact each other. That is, in the coupling direction, which is the direction indicated by the arrow B1, the circumferential attachment position can be restricted at portions that are on both sides of the axis of the rotary shaft 20. Therefore, the accuracy of the mounting position, particularly the accuracy of the mounting direction of the neutral valve portion 30 around the axis of the rotary shaft 20 can be easily improved.

Meanwhile, for example, even when the clearance (gap) between the contact surfaces (the first parallel surfaces 96a and 96b and the second parallel surfaces 97a and 97b) of the recess 95 and the projection 93 is set to be extremely small, the frictional force when the recess 95 is pressed into the projection 95 can be reduced, and the recess 95 and the projection 93 can be smoothly fitted to each other.

Further, the recess 95 and the projection 93 are brought into contact with the first parallel surfaces 96a and 96b and the second parallel surfaces 97a and 97b having different widths, whereby the accuracy of attachment when the recess 95 is press-fitted into the projection 93 can be improved. Further, the mounting position, that is, the amount of press-fitting of the recess 95 into the protrusion 93 can be easily adjusted by reducing the frictional force during mounting. That is, when the recess 95 and the projection 93 are engaged, it is necessary to align the screw hole position of the female screw 31 formed in the recess 95 with the opening 98 formed in the projection 93 of the connection member 91.

As in the present embodiment, by bringing the recess 95 and the projection 93 into contact only on the first parallel surfaces 96a, 96b and the second parallel surfaces 97a, 97b, the position of the threaded hole of the female screw 31 and the opening 98 formed in the projection 93 can be finely adjusted easily and aligned. Thereby, the screw (fastening member) 21d can be easily fastened to the female screw 31 from the through hole 21A of the rotary shaft 20 through the opening 98. Further, by bringing the end surfaces 93m into contact with the end surfaces 95m, mutual positioning in the connecting direction as the direction indicated by the arrow B1 in fig. 12 can be performed.

In the present embodiment, the connection member 91 is provided with the projection 93 and the recess 95 is provided at one end of the neutral valve portion 30, but the configuration may be reversed. That is, a recess is formed in a connecting member fixed to the rotary shaft 20, and a projection fitted into the recess is formed at one end of the neutral valve portion.

[ Movable valve portion 40, movable valve portion (second movable valve portion) 50, and movable valve frame portion (first movable valve portion) 60]

The movable valve portion 40 has a substantially disc shape, and includes a movable valve plate portion 50 formed substantially concentrically with the circular portion 30a, and a substantially annular movable valve frame portion 60 disposed so as to surround the periphery of the movable valve plate portion 50. The movable valve frame portion 60 is connected to the neutral valve portion 30 so as to be slidable in the flow passage H direction.

The movable valve portion 50 is slidably fitted to the movable valve frame portion 60. The movable valve piece portion 50 and the movable valve frame portion 60 can be moved while sliding in the directions (reciprocating directions) indicated by reference numerals B1 and B2 by the main spring 70 and the annular cylinder 80. Here, the directions indicated by reference numerals B1 and B2 are directions perpendicular to the surfaces of the movable valve sheet portion 50 and the movable valve frame portion 60, and are flow passage H directions parallel to the axial direction of the rotary shaft 20.

In addition, an inner peripheral crank portion 50c is formed in the entire region near the outer periphery of the movable valve sheet portion 50. In addition, an outer peripheral crank portion 60c is formed in the entire area near the inner periphery of the movable valve frame portion 60.

In the present embodiment, the outer circumferential crank portion 60c and the inner circumferential crank portion 50c are slidably fitted to each other via sliding surfaces 50b, 60b parallel to the flow path H direction.

A first seal portion 61 (main seal portion) is provided on a surface of the movable valve frame portion 60 that faces (abuts) the inner surface of the valve box 10, and the first seal portion 61 is formed in an annular shape corresponding to the shape of the first opening portion 12a, and is formed by, for example, an O-ring or the like.

The first seal portion 61 is in contact with the inner surface 15a of the valve housing 10, which is the peripheral edge of the first opening portion 12a, in a state where the movable valve portion 40 covers the first opening portion 12a when the valve is closed, and is pressed by the movable valve frame portion 60 and the inner surface of the valve housing 10. Thereby, the first space is surely isolated from the second space (the blocked state is ensured).

[ Main spring (first urging portion) 70]

The main spring (first urging portion) 70 is disposed in the first peripheral region 40b adjacent to the first peripheral region 40a which is the outermost periphery of the movable valve portion 40. The main spring 70 generates a restoring force to urge the movable valve frame portion 60 toward the first opening portion 12a (B1 direction) and to urge the movable valve portion 50 toward the second opening portion 12B (B2 direction).

Thus, in the valve closed state by the movable valve portion 40, the main spring 70 applies a force (bias) to the movable valve plate portion 50, and presses the movable valve plate portion 50 toward the inner surface 15b of the valve housing 10 located around the second opening portion 12b, so that the inner surface 15b and the reaction force transmission portion 59 of the movable valve plate portion 50 are brought into contact with each other. At the same time, the main spring 70 applies a force (bias) to the movable valve frame portion 60, and presses the movable valve frame portion 60 toward the inner surface 15a of the valve housing 10 located around the first opening portion 12a, so that the inner surface 15a abuts against the first seal portion 61 of the movable valve frame portion 60.

In the present embodiment, the main spring 70 is an elastic member (e.g., a spring, rubber, or a sealed air damper). The main spring 70 is fitted into a recess 50a provided in the movable valve portion 50 so as to open toward the second opening portion 12b and a recess 60a provided in the movable valve frame portion 60 so as to open toward the first opening portion 12a at a position opposite to the recess 50 a.

The main spring 70 has a first end and a second end. The first end abuts against the bottom surface of the recess 50a of the movable valve portion 50. The second end abuts against the top surface of the recess 60a of the movable valve frame portion 60. As shown in fig. 1, a plurality of first biasing portions 70 are provided at equal intervals in the circumferential direction in the annular movable valve frame portion 60.

The natural length of the elastic member constituting the main spring 70 is greater than the distance between the bottom surface of the recess 50a of the movable valve disc portion 50 and the top surface of the recess 60a of the movable valve frame portion 60 in a state where the seal portion 61 of the movable valve frame portion 60 and the reaction force transmitting portion 59 of the movable valve disc portion 50 respectively press the inner surface 15a and the inner surface 15b of the valve housing 10, which are the maximum thickness dimension of the movable valve portion 40. Therefore, the main spring 70 disposed inside the recess 50a and the recess 60a generates an elastic restoring force (extending force, biasing force) while being compressed by the bottom surface of the recess 50a of the movable valve plate portion 50 and the top surface of the recess 60a of the movable valve frame portion 60. By the action of this elastic restoring force, the movable valve frame portion 60 slides in the B1 direction and the movable valve piece portion 50 slides in the B2 direction, and the first seal portion 61 and the reaction force transmission portion 59 abut against and press the inner surface of the valve housing 10, thereby performing the valve closing operation.

In addition, the main spring 70 is disposed in the second peripheral region 40b close to the first seal portion 61 in order to reliably close the gate valve 1 by efficiently transmitting the pressing force against the first seal portion 61. Specifically, a protrusion is provided at an outer circumferential position directly below the first seal portion 61 as a reaction force transmission portion 59 to be described later. On the other hand, as the radial position of the movable valve portion 50, the main spring 70 is located at a position opposite to the first seal portion 61 from the ridge (reaction force transmitting portion) 59. Thus, the biasing force of the main spring 70 is efficiently transmitted to the seal portion 61 of the movable valve frame portion 60 and the reaction force transmitting portion 59 of the movable valve disc portion 50, and the reliability of the sealing of the valve due to the deformation of the first seal portion 61 can be improved.

In addition, the main spring 70 may be disposed in the second peripheral region 40b that is in the vicinity directly below the first seal portion 61 so as to be able to directly press the first seal portion 61. In this case, in the gate valve, since the first biasing portion 70 is provided in the movable valve frame portion 60, the first biasing portion 70 can be positioned directly below the first seal portion 61.

As described above, in the gate valve 1, as an actuator for performing the valve closing operation and the valve opening operation, the main spring 70 for performing the valve closing operation and the second biasing portion 80 (described later) for performing the valve opening operation are provided in proximity to each other. In this configuration, the main spring 70 and the second biasing portion 80 are disposed adjacent to each other in the radial direction in the peripheral region (the first peripheral region 40a and the second peripheral region 40b) of the movable valve portion 40 close to the first seal portion 61. In addition, the main spring 70 is located in the vicinity directly below the first seal portion 61. That is, the gate valve 1 is structured such that the positional relationship between the first seal portion 61, the reaction force transmission portion 59, and the main spring 70 is set to a structure in which a moment load having an operating point and a fulcrum is applied, and the structure can effectively perform sealing.

Further, the biasing force of the main spring 70 is set in a direction to enlarge the movable valve portion 50 and the movable valve frame portion 60, that is, in a direction to increase the thickness of the movable valve portion 40 so as to press the seal portion 61 of the movable valve frame portion 60 and the reaction force transmitting portion 59 of the movable valve portion 50 against the inner surfaces 15a, 15b of the valve housing 10. Therefore, even when the power supply (energy supply) from the utility to the device including the gate valve 1 is stopped due to a power failure or the like, the gate valve 1 can be reliably closed by only the mechanical force generated by the main spring 70. Therefore, a fail-safe gate valve can be reliably realized.

On the other hand, in a gate valve having a structure for applying a biasing force to reduce the thickness of the movable valve portion 40 or a gate valve having a structure for performing a valve closing operation by energy such as power supplied from an application, the valve closing operation may not be performed when the supply of energy from the application to the apparatus is stopped. Therefore, this structure cannot realize a fail-safe gate valve.

[ annular Cylinder (second urging portion) 80]

The annular cylinder 80 is disposed in the first peripheral region 40a which is the outermost periphery of the movable valve portion 40. When compressed air as a driving fluid is supplied to the annular cylinder 80 in the annular cylinder 80, a force (urging force, force generated by the compressed air) is generated to move the movable valve frame portion 60 toward the second opening portion 12B (direction B2). At the same time, a force (urging force, force by compressed air) is generated to move the movable valve portion 50 toward the first opening portion 12a (direction B1). Thus, the force generated by the compressed air is larger than the biasing force of the main spring 70, and the movable valve frame portion 60 is moved away from the inner surface 15a of the valve housing 10 located around the first opening portion 12a, and the movable valve portion 50 is moved away from the inner surface 15b of the valve housing 10 located around the second opening portion 12 b.

Thus, the movable valve body 40 is positioned at the center in the thickness direction of the valve housing 10 in the flow passage H direction by the biasing force of an auxiliary spring (third biasing portion) 90 described later, and is rotatable in the valve housing 10.

In the movable valve portion 40, the first peripheral region 40a is located inside the seal portion 61 of the annular movable valve frame portion 60 and the reaction force transmission portion 59 of the movable valve portion 50. Meanwhile, in the movable valve portion 40, the second peripheral region 40b is located inside the first peripheral region 40 a. That is, the main spring 70 is disposed inside the annular cylinder 80 in the radial direction of the movable valve portion 40. In other words, the annular cylinder 80 is adjacent to the main spring 70 in a direction intersecting the direction in which the movable valve plate portion 50 and the movable valve frame portion 60 slide (the flow passage H direction). That is, the annular cylinder 80 is located between the seal portion 61 and the reaction force transmission portion 59 and the main spring 70 in the radial direction of the movable valve portion 40.

In the present embodiment, the annular cylinder 80 is a single cylinder (gap) provided between the movable valve portion 50 and the movable valve frame portion 60.

Specifically, the annular cylinder 80 is formed in a state in which the concave portion 60d of the movable valve frame portion 60 that opens toward the first opening portion 12a and the convex portion 50d of the movable valve piece portion 50 that protrudes toward the second opening portion 12b are engaged with each other, and is formed in a manner in which these annular concave portion 60d and annular convex portion 50d slide. The annular cylinder 80 is configured by an annular space formed in the peripheral edge portion of the movable valve frame portion 60 and a ridge (annular projection) formed in the outermost periphery of the movable valve plate portion 50, and functions as one annular cylinder (annular gap). In other words, the annular cylinder is formed to surround the flow passage H.

When compressed air as a driving fluid is supplied to the annular cylinder 80, an expansion force (urging force) for expanding the volume of the second urging portion 80 is generated in the directions B1 and B2. In the case where the magnitude of the expansion force is larger than the restoring force generated in the main spring 70, the expansion force is larger than the acting force of the main spring 70. Thereby, the main spring 70 is compressed, the movable valve sheet portion 50 slides in the direction B1, and the movable valve frame portion 60 slides in the direction B2 to reduce the dimension of the movable valve body 40 in the thickness direction, so that the first seal portion 61 is separated from the inner surface 15a of the valve housing 10, and the reaction force transmission portion 59 is separated from the inner surface 15B of the valve housing 10 to perform a valve opening operation. At this time, the annular concave portion 60d and the annular convex portion 50d slide, so that the movement direction of the movable valve piece portion 50 and the movable valve frame portion 60 is restricted only in the flow passage direction, and the positions of the movable valve piece portion 50 and the movable valve frame portion 60 are restricted, and the movable valve piece portion 50 and the reaction force transmitting portion 59 move in parallel from the state of being in contact with the inner surfaces 15a and 15b of the valve housing 10. That is, the annular cylinder 80 can restrict the relative movement direction and posture of the movable valve piece portion 50 and the movable valve frame portion 60.

[ auxiliary spring (third urging portion) 90]

The assist spring 90 is provided between the neutral valve portion 30 and the movable valve frame portion 60. When the thickness dimension of the movable valve body 40 is reduced with respect to the neutral valve portion 30 located at the substantially center in the flow passage direction of the valve housing 10, the auxiliary spring 90 urges the movable valve body 40 toward the center of the valve housing 10.

The assist spring 90 is provided in a rod-shaped position regulating portion 65 that is connected to the movable valve frame portion 60 by passing through an opening 30a provided in an outer peripheral position (right position in fig. 2 and 4) of the neutral valve portion 30. The auxiliary spring 90 is also an elastic member (for example, a spring, rubber, or a sealed air damper) as in the main spring 70.

The assist spring 90 is locked to the flange portion 30B provided in the vicinity of the first opening portion 12a of the opening 30a of the neutral valve portion 30 and the distal end 65a of the position regulating portion 65, and urges the movable valve frame portion 60 in the direction B2 moving toward the second opening portion 12B.

The assist spring 90 biases the movable valve frame portion 60 located closer to the first opening portion 12a than the neutral valve portion 30 toward the second opening portion 12 b. When the seal portion 61 of the movable valve frame portion 60 abuts against the inner surface 15a of the valve housing 10 located around the first opening portion 12a, the auxiliary spring 90 biases the movable valve frame portion 60 away from the inner surface 15a of the valve housing 10 located around the first opening portion 12a when compressed air as the driving fluid is supplied to the annular cylinder 80.

Thus, when the compressed air is supplied to the annular cylinder 80, the movable valve body 40 moves toward the substantial center in the flow passage direction of the valve housing 10, and finally the posture of the movable valve body 40 is controlled so that the movable valve body 40 is positioned at the substantial center in the flow passage direction of the valve housing 10. The biasing force of the assist spring 90 is much smaller than the difference between the biasing force of the main spring 70 and the biasing force of the annular cylinder 80. That is, since the auxiliary spring 90 only needs to change the thickness dimension of the valve body, the auxiliary spring 90 can be an extremely small spring as compared with the main spring 70 or the annular cylinder 80 as the actuator or the active spring for realizing the valve-closed state.

As described above, the gate valve 1 is provided with the main spring 70 for increasing the thickness of the movable valve body 40, the annular cylinder 80 for reducing the thickness of the movable valve body 40, and the auxiliary spring 90 for controlling the posture of the movable valve body 40 so that the movable valve body 40 is positioned on the center side of the valve housing 10 in the flow path direction, as actuators for performing the valve closing operation and the valve opening operation.

In this configuration, the main spring 70 and the annular cylinder 80 are arranged in parallel so as to be close to each other in the peripheral region of the movable valve portion 40 close to the first seal portion 61.

The annular cylinder 80 is constructed as one annular cylinder body provided between the movable valve disc portion 50 and the movable valve frame portion 60. According to this configuration, if the single supply passage 41 for supplying compressed air to the second biasing portion 80 in one direction is provided, the compressed air can be supplied to the inside of the annular cylinder along the annular cylinder 80. Further, the movable valve body 40 can be expanded and contracted in thickness (valve opening operation and valve closing operation). Further, the position in the flow passage direction of the movable valve body 40 can be easily maintained near the center of the valve housing 10 along with the expansion and contraction of the movable valve body 40 by the auxiliary spring 90 in this operation. Therefore, an actuator having a simple and compact structure can be realized.

Since the annular cylinder 80 is used for the valve opening operation, the magnitude (output) of the force generated in the second biasing portion 80 may be a magnitude (output) capable of compressing the first biasing portion 70.

In the present embodiment, one movable valve portion 40 that can change the dimension in the thickness direction is configured by the movable valve plate portion 50 and the movable valve frame portion 60, and therefore, there is no need to provide two movable valve portions, and a movable valve portion having a simple and compact structure can be realized.

Further, the force of the actuator, particularly the force applied when the movable valve body 40 is sealed in order to maintain the valve closed state, does not act on the neutral valve portion 30. Therefore, the neutral valve portion 30 may have a strength enough to swing the valve body as a pendulum valve. Further, the force of the actuator, particularly the force applied when the movable valve body 40 is sealed in order to maintain the valve-closed state, does not act on the rotary shaft 20. Therefore, the rotary shaft 20 may have a strength enough to swing the valve body as a pendulum valve. At the same time, the output of the swing mechanism of the movable valve body 40 can be suppressed as compared with a structure in which the rotary shaft 20 requires a moment for valve sealing, and therefore the turning mechanism of the rotary shaft 20 can be downsized.

In this configuration, the rigidity may be set to a strength that supports the weight of the movable valve portion 40 when the movable valve portion 40 is rotated between the retracted position and the valve opening/closing position, in addition to the strength of the neutral valve portion 30.

Fig. 2 shows a portion where the movable valve plate portion 50 and the movable valve frame portion 60 are fitted to each other, a portion where the neutral valve portion 30 and the movable valve plate portion 50 are fitted to each other, and a portion where the first biasing portion 70 and the guide pin 62 are provided.

[ second seal parts (double seal parts) 51a, 51b and third seal parts (double seal parts) 52a, 52b ]

Annular second seal portions 51a and 51b and third seal portions 52a and 52b such as O-rings are provided on the outer peripheral surface of the annular projection (ridge) 50d of the movable valve plate portion 50, and the second seal portions 51a and 51b and the third seal portions 52a and 52b are a double-layer seal portion that seals between the movable valve plate portion 50 and the movable valve frame portion 60 while abutting against the inner peripheral surface of the annular recess 60d of the movable valve frame portion 60.

Specifically, the second seal portions 51a and 51b are provided on the first outer peripheral surface 50f located radially outward of the annular projection (ridge) 50d of the movable valve portion 50. Third seal portions 52a and 52b are provided on a second inner peripheral surface 50g located radially inward of the first outer peripheral surface 50 f. The second seal portions 51a, 51b abut against the first inner peripheral surface 60f of the movable valve frame portion 60, and the third seal portions 52a, 52b abut against the second outer peripheral surface 60g of the movable valve frame portion 60.

The second sealing portions 51a and 51b block the annular cylinder 80, which is a high-pressure space, and the hollow portion 11, which is a low-pressure space or the like, near the first opening portion 12a, and ensure a blocked state. Similarly, the third sealing portions 52a and 52b block the annular cylinder 80, which is a high-pressure space, and the hollow portion 11, which is a low-pressure space or the like, near the second opening portion 12b, and ensure a blocked state.

The second sealing portions 51a and 51b can secure the blocked state while blocking the annular cylinder 80, which is supplied with the driving compressed air and becomes a high-pressure space, and the first space side communicating with the first opening 12a, which is a low-pressure space, for example. Similarly, the third sealing portions 52a and 52b can ensure a blocked state while blocking the annular cylinder 80, which is a high-pressure space, and the second space side, which is a low-pressure space or the like, close to the second opening 12 b.

[ guide pin 62]

The guide pin 62 is fixedly provided to the movable valve frame portion 60 and is erected in the flow passage direction, and the guide pin 62 is configured by a rod-shaped body having a uniform thickness. The guide pin 62 penetrates the annular cylinder 80 and is fitted into a hole 50h formed in the annular projection (ridge) 50d of the movable valve sheet portion 50.

The guide pin 62 surely guides the position restriction of the movable spool part 50 and the movable spool part 60 so that the sliding direction of the movable spool part 50 and the movable spool part 60 is not deviated from the directions indicated by B1 and B2, and so that the movable spool part 50 and the movable spool part 60 move in parallel without changing the postures of the movable spool part 50 and the movable spool part 60 when the movable spool part 50 and the movable spool part 60 slide.

Thereby, the movable valve portion 50 and the movable valve frame portion 60 are prevented from moving in the oblique direction with respect to the reference numerals B1, B2. At the same time, even when the positions of the movable valve sheet portion 50 and the movable valve frame portion 60 in the flow path direction are changed from the closed state, that is, the state in which the seal portion 61 and the reaction force transmission portion 59 are in contact with the inner surfaces 15a and 15b of the valve housing 10, respectively, the movable valve frame portion 60 moves in parallel while maintaining the parallel state, thereby preventing the inclination of the movable valve sheet portion 50 and the movable valve frame portion 60.

In this configuration, the movable valve plate portion 50 and the movable valve frame portion 60 can be positioned relative to each other, and can perform the valve closing operation and the valve opening operation while being relatively moved while maintaining the state parallel to the directions indicated by reference numerals B1 and B2. Accordingly, during the valve opening operation, a uniform pressing force can be generated in the first seal portion 61 provided in the movable valve frame portion 60, and a seal structure that suppresses leakage can be realized.

In the configuration including the guide pin 62, when the installation posture of the gate valve 1 in the vacuum apparatus is not determined, that is, when the installation direction of the gate valve 1 is free, the weight load of the movable valve body 40 can be prevented from being locally applied to the second seal portions 51a and 51b and the third seal portions 52a and 52 b. For example, when the gate valve 1 is attached so that the gravity acts perpendicularly to the direction in which the movable valve piece portion 50 and the movable valve frame portion 60 slide, the weight of the movable valve piece portion 50 and the movable valve frame portion 60 as the sliding members is applied to the guide pins 62. Therefore, the weights of the movable valve portion 50 and the movable valve frame portion 60 are prevented from being directly applied to the second seal portions 51a, 51b and the third seal portions 52a, 52b (O-rings). Accordingly, regardless of the installation posture of the gate valve 1, the life of the seal portion is not shortened, and the leakage prevention effect can be ensured and maintained.

The guide pin 62 is disposed to penetrate the annular cylinder 80 in order to reduce the area of the sliding surface between the guide pin 62 and the hole 50h and to isolate the guide pin 62 from the first space and the second space outside the gate valve 1.

By disposing the guide pin 62 in the annular cylinder 80 in this manner, the movable valve portion 50 and the movable valve frame portion 60 can be smoothly slid with respect to each other.

Further, if the guide pin obtains sufficient strength, it is possible to prevent the direction in which the movable valve frame portion 60 slides from being deviated even in a gate valve having a large diameter. Further, the guide pin 62 is disposed in a plane perpendicular to the flow path even in the movable valve portion 40 having a special shape, and can be used as a gate valve having a more excellent opening and closing operation by appropriately dispersing the load.

[ wipers 53, 54]

An annular wiper 53 is provided on the first outer peripheral surface 50f located radially outward of the annular projection (ridge) 50d of the movable valve portion 50, and abuts against the inner peripheral surface of the movable valve frame portion 60. Similarly, an annular wiper 54 that abuts against the outer peripheral surface of the movable valve frame portion 60 is provided on the second inner peripheral surface 50g, which is the inner side of the first outer peripheral surface 50f in the radial direction of the annular projection (ridge) 50d of the movable valve plate portion 50.

The wipers 53 and 54 have a function of lubricating or cleaning the inner peripheral surface of the recess 60d of the movable valve frame portion 60 by the valve opening operation and the valve closing operation.

[ intermediate atmospheric chambers 55, 56]

An intermediate atmospheric chamber 55 serving as an atmospheric pressure space (gap) is provided on the surface of the annular cylinder 80 blocked by the second sealing portions 51a and 51 b. Similarly, by providing the intermediate atmospheric chamber 56 as an atmospheric pressure space (gap) on the surface of the annular cylinder 80 blocked by the third sealing portions 52a and 52b, even when the first seal is broken during pressurization of the annular cylinder 80, a structure can be obtained in which compressed air (driving gas) is prevented from escaping to the outside of the gate valve and being discharged into the valve box 10.

At the same time, the pressure of these intermediate atmospheric chambers 55, 56 can be monitored via the communication channel. That is, a pressure gauge is provided outside the gate valve 1 and connected by a communication passage to measure the pressure in the intermediate atmospheric chambers 55 and 56, and the pressure is monitored by the user.

[ connecting pin 69, supply channel 41]

Fig. 13 is an enlarged view showing a main part of a member located in the vicinity of the connecting pin.

As shown by the two-dot chain line in the figure, the gate valve 1 is provided with a supply passage 41 for supplying a driving gas to the annular cylinder 80. The supply passage 41 is provided to communicate with a driving gas supply device, not shown, provided outside the gate valve 1 via the inside of the main body of the movable valve frame portion 60, the inside of the main body of the neutral valve portion 30, and the inside of the rotary shaft 10.

The supply passage 41 is provided with a connection pin portion 69, and the connection pin portion 69 is slidably connected between the movable valve frame portion 60 and the neutral valve portion 30 so as to be able to supply driving gas even when the positions of the movable valve frame portion 60 and the neutral valve portion 30 in the flow passage direction change.

The connecting pin portion 69 is configured by a hole portion 38 having a circular cross section and bored in the neutral valve portion 30 in parallel with the flow path direction, and a rod-like connecting pin 68 rotatably fitted to the hole portion 38. The inner surface 38a of the hole 38 has a diameter smaller on the bottom side than the inner surface 38a on the opening side, and accordingly, the diameter of the connecting pin 68 is also smaller at the tip end 68b of the base portion 68 a. A step 38c and a step 68c are formed in the portion where the diameter size changes.

As shown by the two-dot chain line in the figure, the connection pin portion 69 is formed with a supply passage 41 near the central axis thereof and has a tubular shape, and the supply passage 41 inside the movable valve frame portion 60 communicates therewith. The supply path 41 opens at the distal end surface 68d of the connecting pin 68, and the supply path 41 formed in the main body of the neutral valve portion 30 communicates with the pressurizing space 69a formed by the distal end surface 68d and the space near the bottom 38d of the hole portion 38.

The compressed air supplied from the driving gas supply device is discharged into the space 69a through the supply passage 41 inside the neutral valve unit 30, and is supplied to the annular cylinder 80 through the supply passage 41 inside the connection pin unit 69 and the supply passage 41 inside the movable valve frame unit 60.

The connecting pin portion 69 abuts the inner peripheral surface 38a of the hole portion 38 on the outer peripheral surface 68a of the connecting pin 68, and abuts the inner peripheral surface 38b of the hole portion 38 on the outer peripheral surface 68b of the connecting pin portion 68.

A double seal is provided on the connecting pin 68.

When the connecting pin 68 moves in the axial direction (flow passage direction) in the hole 38, a double seal portion is provided not only between the front end surface 68d as a pressing surface and the bottom surface 38d but also on a surface in the sliding direction. The double-layer sealing portion blocks the pressurized space 69a, which becomes a high-pressure space to which the compressed air for driving is supplied, and the second space side communicating with the second opening 12b, which is a low-pressure space, for example.

The sealing portion can ensure a blocked state of the pressurizing space 69a and the hollow portion 11.

Specifically, the connecting pin 68 is formed with a double-layer seal portion that seals between the connecting pin 68 and the hole portion 38. In the double-seal structure, an O-ring or the like and an annular rough seal portion 68f as a circumferential groove in which the O-ring or the like is embedded are provided on the outer circumferential surface 68a, and an O-ring or the like and an annular small seal portion 68g as a circumferential groove in which the O-ring or the like is embedded are provided on the outer circumferential surface 68 b.

At the same time, an annular intermediate atmospheric chamber 69c formed by the step 68c and the step 38c is located between the double seals and is connected to the communication passage 42, not shown. This allows the compressed air to be discharged into the valve box 10, thereby preventing adverse effects on the inside of the gate valve 1, the first space, and the second space.

In particular, in the above configuration, sealing is not performed between the tip end surface 68d and the bottom surface 38d which become pressure surfaces and whose distance changes, but sealing is performed directly between the outer peripheral surface 68a and the inner peripheral surface 38a, and between the outer peripheral surface 68b and the inner peripheral surface 38b which do not become pressure surfaces and whose distance is constant, which do become sliding surfaces. Therefore, a reliable sealed state can be maintained.

With the configuration of the seal portions 68f and 68g, the same operational effects as those of the second seal portions (double seal portions) 51a and 51b, the third seal portions (double seal portions) 52a and 52b, and the guide pin 62 in the annular cylinder 80 can be obtained.

In the hole 38, during the movement of the connecting pin 68 in the axial direction (flow passage direction) or when the relative position in the flow passage direction changes due to the movement, the compressed air supplied from the driving gas supply device is also ejected into the space 69a through the supply passage 41 inside the neutral valve unit 30. The compressed air is stably supplied to the annular cylinder 80 through the space 69a with a changed volume, the supply passage 41 inside the connection pin portion 69, and the supply passage 41 inside the movable valve frame portion 60.

In fig. 13, as a connecting pin portion 69 located above the connecting pin 68, a floating pin 68A (connecting pin) connected to the movable valve frame portion 60 is engaged with the through hole 67.

The connecting pin portion 69 has a through hole 67 having a circular cross section and formed in the movable valve frame portion 60 in parallel with the flow path direction, and a rod-like floating pin 68A having a flange portion 68Aa is fitted in the through hole 67 so as to be rotatable and to be capable of fine movement in the radial direction and to be inclined to a minimum.

The flange inner surface 67a of the through hole 67 has a diameter larger than the diameter of the hole 38 facing the movable valve frame portion 60, corresponding to the diameter of the flange portion 68 Aa. The right angle of the gas connecting position inner surface 38b is smaller than the diameter of the flange inner surface 67a of the opening side. The support position inner surface 67c on the upper penetration side in fig. 13 has a smaller diameter than the gas connection position inner surface 67 b. The outer inner surface 67d on the upper penetration side in fig. 13 has a larger diameter than the support position inner surface 67 c.

The diameter of the floating pin 68A corresponds to the diameter of the through hole 67. The diameter of the gas connecting portion 68Ab is smaller than the diameter of the flange portion 68 Aa. The diameter of the fixed end 68Ac is smaller than the diameter of the gas connecting portion 68 Ab.

A fixing groove 68Ad is arranged on the fixing end 68 Ac. A fixing member 68Ae such as a washer fitted to the fixing groove 68Ad abuts against the outer surface 67e of the through hole 67, whereby the floating pin 68A is regulated from moving in the inner direction (downward direction in the drawing) in the axial direction (flow path direction) and fixed to a position.

Seal members 67h and 67j such as O-rings are provided between the facing stepped surface 67f and the stepped surface 67g as the upper seal surface 68Af of the flange portion 68Aa and the upper seal surface 68Ag of the gas connecting portion 68 Ab.

The floating pin 68A is fixed so as to be sandwiched in the opposing direction between the fixed member 68Ae of the fixed end 68Ac, the seal surface 68Af, and the seal members 67h and 67j of the seal surface 68 Ag. Thereby, the floating pin 68A is fixed to the movable valve frame portion 60 in a state of being pressed to the upper side in fig. 13 and not moving in the axial direction (the longitudinal direction of the through hole 67).

Meanwhile, the floating pin 68A is configured such that the seal member 67h is pressed by the seal surface 68Af and the step surface 67f to be deformed, and the seal member 67j is pressed by the seal surface 68Ag and the step surface 67g to be deformed.

In this way, the seal members 67h and 67j, such as O-rings, of the float pin 68A are pressed against the step surfaces 67f and 67g and deformed, thereby sealing the gas connecting portion 68Ab and the connection position inner surface 67 b.

[ sequence Loop SQ ]

Fig. 14 is a circuit diagram showing a drive sequence mechanism.

As shown IN fig. 14, the gate valve 1 of the present embodiment includes a sequence circuit SQ that performs a thickness expansion/contraction (LOCK-FREE) operation of the movable valve portion 40, an expansion/contraction (OPEN-CLOSE) operation of the rotary drive cylinder 110, and a supply of damping air by supplying compressed air supplied from the OP-IN port to the output point FR, the output point main-OP, and the output point main-CL.

In the sequential loop SQ, the output point FR is connected to the supply line 41, the output point main-OP is connected to the extension pressure space 113, and the output point main-CL is connected to the contraction pressure space 22 c.

The output point FR is connected to supply compressed air for thickness reduction of the movable valve portion 40 from the supply passage 41 to a single-acting cylinder composed of an annular cylinder (second biasing portion) 80 and a main spring 70 when the valve closed state is released.

The output point main-CL is connected to be able to supply compressed air as damping air to the contracted pressure space 22c via the supply passage (contracted air port) 22j before the valve opening operation and before the thickness of the movable valve portion 40 is contracted, and is able to be set to a damping pressure state for the rotation driving cylinder 110.

Here, if the Closed (CLOSE) rotational state is not maintained until the movable valve portion 40 contracts when the valve is closed, the valve body rotational position becomes unstable due to contraction of the movable valve portion 40, and the movable valve portion 40 moves due to its own weight, which is not preferable.

The output point main-OP is connected to a rotary drive cylinder 110. Before the thickness of the movable valve portion 40 is contracted IN the case of releasing the closed state of the valve, the output point main-OP can supply compressed air for expansion from the OP-IN port to the expansion pressure space 113 via the expansion vent (supply passage) 114, so that the force generated by the compressed air becomes larger than the biasing force of the biasing portion 120, and the cylinder 110 is rotationally driven to perform the expansion operation.

The sequence circuit SQ includes a spool (pneumatic dual chamber spool) sp1V connected to the OP-IN port, and speed control valves NC1V, NC2V, and NC3V each including a combination of a check valve and a flow rate adjustment valve.

The spool sp1V is operated so as to be switched ON/OFF (ON/OFF) by supplying compressed air for driving from the OP-IN port to the pneumatic sp1V0 side.

The spool valve sp1V is configured to connect the OP-IN port and the main-CL while venting the output point main-OP to the atmosphere (outside) when the signal from the OP-IN port is off, and to release the output point main-CL to the atmosphere while connecting the OP-IN port and the main-OP when the signal from the OP-IN port is on.

Therefore, the spool valve sp1V may be of the following structure: a slidable spool (valve body) is inserted into a cylinder-shaped housing through which two flow paths from an OP-IN port, a communication hole communicating with the outside, and two flow paths connected to an output point main-OP and an output point main-CL pass, and is biased toward the pneumatic sp1V0 side by a biasing portion such as a spring.

In the spool sp1V, a flow path groove corresponding to the surface thereof is formed in the spool (valve body). At the sliding position of the spool (valve body) along the axis, two flow passages from the OP-IN port, a communication hole communicating with the outside, and two flow passages connected to the output point main-OP and the output point main-CL can be connected and cut off.

Further, an adjustment member is provided on the opposite side of the housing (sleeve) from the pneumatic sp1V0, and the adjustment member is capable of receiving the biasing force of a spring or the like and is set so as to be capable of adjusting the position in the axial direction of the sleeve.

By adjusting the position in the axial direction at which the adjustment member is fixed to the housing, the biasing force of the spring changes, and the threshold value of the passage connection and disconnection can be adjusted in the pressure supplied from the pneumatic sp1V0 side.

Accordingly, IN the spool sp1V, the pressure supplied from the OP-IN port to the pneumatic sp1V0 side can be set to a predetermined value IN advance, and it is set so that the valve operation is not performed even when there is a pressure fluctuation equal to or less than the predetermined value.

Further, the application of pressure from the OP-IN port to the pneumatic sp1V0 may be regarded as a spool slide valve operation start signal applied to the spool sp 1V. That is, the valve operation can be performed only by a signal from the OP-IN port of one stage.

The speed control valve NC1V is connected to a flow path branched from the OP-IN port and a flow path toward the output point main-OP and the output point main-CL (a flow path connected to the spool sp 1V). In addition, the flow path from the spool sp1V to the output point main-OP is in parallel with the flow path from the spool sp1V to the output point main-CL. The flow path of pneumatic sp1V0 from the speed control valve NC1V to the spool sp1V is branched, and the branched flow path is connected to the output point FR.

The speed control valve NC1V is combined with a flow rate adjustment valve and a check valve, and the flow rate adjustment valve and the check valve are connected IN parallel so as to prevent the flow of compressed air (exhibit the check function of the check valve, and reverse direction) IN the direction from the OP-IN port toward the pneumatic sp1V0 side of the spool sp1V and the output point FR.

The speed control valve NC2V is connected to a flow path from the spool sp1V to the output point main-OP.

The speed control valve NC2V is combined with a flow rate adjustment valve and a check valve, and the flow rate adjustment valve and the check valve are connected in parallel so as to allow a flow of compressed air in a direction from the spool sp1V to the output point main-OP (the check function of the check valve is not exerted, and the check valve is in the forward direction).

The speed control valve NC3V is connected to a flow path from the spool valve sp1V to the output point main-CL.

The speed control valve NC3V is combined with a flow rate adjustment valve and a check valve, and the flow rate adjustment valve and the check valve are connected in parallel so as to allow a flow of compressed air in a direction from the spool sp1V to the output point main-CL (the check function of the check valve is not exerted, and the check valve is in the forward direction).

When the spool sp1V is operated so that the signal from the OP-IN port is ON, the speed control valve NC1V delays the ON of the signal from the OP-IN port.

At the same time, when the signal from the OP-IN port is on, the supply to the pneumatic sp1V0 side and the output point FR is delayed by the speed control valve NC1V compared with the flow from the OP-IN port to the output point main-OP or the output point main-OP.

Further, during the operation of the spool sp1V, the flow from the output point main-OP is delayed by the speed control valve NC2V compared to the switching by the operation of the spool sp 1V.

Similarly, when the spool sp1V is operated, the flow from the output point main-CL is delayed from the switching by the operation of the spool sp1V by the speed control valve NC 3V.

Next, the pressure state and the pneumatic state in the sequence circuit SQ will be described.

Fig. 14 to 18 show the pressure state in the sequence circuit SQ, the thick line shows the high pressure PHi state, the thin line shows the low pressure PLo state, and the thick broken line shows the damping pressure Pd.

In fig. 14 to 18, for the sake of explanation, a state in which the two components actually occur simultaneously is shown in different drawings.

First, a LOCK-CLOSE (LOCK-CLOSE) state in which the sealing gate valve 1 is closed is set as an initial state.

At this time, the movable valve portion 40 is in a Closed (CLOSE) state as the valve closed position E2 (fig. 1), and is in a LOCK (LOCK) state (closed state) in which the thickness of the movable valve portion 40 is maximum. At the same time, the piston 112 is in the retracted position Pb.

IN the lock-off state, as a pressure state of the sequence circuit SQ, as shown IN fig. 14, IN an input of one system IN which compressed air is supplied on the input side, the compressed air is not supplied to the OP-IN port for performing the valve operation, and a low pressure PLo state (indicated by a thin line) almost equal to the atmospheric pressure is obtained.

Therefore, as shown IN fig. 14, the pneumatic sp1V0 side of the spool sp1V is also IN a low pressure PLo state (indicated by thin lines) equal to the atmospheric pressure, and therefore, the flow path from the OP-IN port and the flow path of the output point main-CL are IN a signal cutoff state by the biasing force of the spring. Meanwhile, the flow passage on the main-OP side of the output point communicates with the atmosphere (outside).

Thus, the output point FR, the output point main-OP, and the output point main-CL are all in a low pressure PLo state (indicated by thin lines) that is almost equal to the atmospheric pressure. Therefore, although the contraction pressure space 22c and the expansion pressure space 113 of the rotation driving cylinder 110 are not pressurized, the piston 112 is biased by the biasing portion 120 to be at the contraction position Pb. Thus, normally-closed can be achieved.

Next, as shown IN fig. 15, the valve opening command is switched to a high-pressure PHi state (indicated by a thick line) IN which the OP-IN port is caused to exceed the operation threshold value by being supplied with compressed air as a pressure state on the input side.

Accordingly, as shown IN fig. 15, the OP-IN port is IN a pressurized state, and compressed air flows into the output point main-CL. At this time, the speed control valve NC3V is pressurized smoothly because the direction from the OP-IN port side to the output point main-CL is the forward direction.

Thus, the output point master-CL becomes a damping pressure Pd state (indicated by a thick broken line) in which the pressure thereof is higher than a low pressure PLo state (indicated by a thin line) that is substantially the same as the atmospheric pressure but lower than a high pressure PHi state (indicated by a thick line) that is set as an operation threshold value of the rotation driving cylinder 110. Similarly, the contraction pressure space 22c of the rotation driving cylinder 110 is in the state of the damping pressure Pd.

At this time, the pressure in the contracted pressure space 22c in the state of the damping pressure Pd is lower than the pressure in the state of the high pressure PHi and does not reach the operation threshold of the rotation driving cylinder 110, so the piston 112 urged by the urging portion 120 does not move.

At this time, the pneumatic sp1V0 side of the spool sp1V is IN a state of pressure rise delay by the speed control valve NC1V connected to the OP-IN port, and the state IN which the spool sp1V does not move is maintained.

The output point FR also enters a state where the pressure rises though it is delayed with respect to the OP-IN port. Along with this, the pressure of the annular cylinder 80 connected to the output point FR also rises.

Then, the pressure at the output point FR also rises, and as shown IN fig. 16, if the high-pressure PHi state (indicated by a thick line) is the same as that of the OP-IN port, the output point FR also becomes the pressurized state of the high-pressure PHi state (indicated by a thick line).

At this time, as the pressure of the annular cylinder 80 increases, the force generated by the cylinder becomes larger than the biasing force of the main spring 70, the movable valve plate portion 50 slides in the direction B1 and the movable valve frame portion 60 slides in the direction B2, and the movable valve portion 40 is reduced in size in the thickness direction and is operated to the closed release state, thereby being brought into a FREE-closed (FREE-CLOSE) state.

At this time, since the biasing portion 120 biases, the turning operation of the movable valve portion 40 is not started, and the valve closing position (release position) E2 is maintained.

When the pressure at the output point FR rises and reaches the same high-pressure PHi state (indicated by a thick line) as that at the OP-IN port, the pneumatic sp1V0 side of the spool sp1V becomes a pressurized state, and if the pressure exceeds a threshold value, the force generated by the compressed air due to the spool sp1V becomes larger than the biasing force of the spring, and the spool moves rightward IN fig. 16, and the signal on state is switched.

In the switching operation to the signal on state in the spool valve sp1V, the threshold value of the operation is controlled by the speed control valve NC1V, and the pressure on the pneumatic sp1V0 side rises to a predetermined value after the compressed air flows until the contracted pressure space 22c is in the damping pressure Pd state.

Then, as shown IN fig. 17, when the spool sp1V is switched to the signal on state, the flow path from the OP-IN port and the flow path on the output point main-OP side communicate with each other. Meanwhile, the flow passage on the output point main-CL side is communicated to the atmosphere side through the spool valve sp 1V.

Thereby, the output point main-OP connected to the OP-IN port is pressurized to the same high-pressure PHi state (indicated by a thick line) as the OP-IN port. At this time, the speed control valve NC2V is pressurized smoothly because the direction from the OP-IN port side to the output point main-OP is the forward direction.

Then, the extension pressure space 113 of the rotation drive cylinder 110 connected to the output point main-OP instantaneously becomes a high pressure PHi state (indicated by a thick line), and the contraction pressure space 22c of the rotation drive cylinder 110 connected to the output point main-CL becomes a damping pressure Pd state (indicated by a thick broken line) lower than the high pressure PHi, so that a pressure difference is generated between the contraction pressure space 22c and the extension pressure space 113.

As a result, the force generated by the compressed air is larger than the biasing force of the spring member 120s of the biasing portion 120, and the piston 112 starts moving from the contraction position Pb toward the expansion position Pa side in the rotation driving cylinder 110.

At this time, the output point FR and the annular cylinder 80 maintain the high pressure PHi state (indicated by a thick line), and maintain the state in which the dimension of the movable valve portion 40 in the thickness direction is reduced.

At this time, the rotary shaft 20 and the neutral valve body 5 are rotated in accordance with the movement of the piston 112 caused by the pressurization of the extension pressure space 113, and the movable valve portion 40 is rotated from the closing position (closing release position) E2 (fig. 1) toward the retracted position E1 (fig. 1), thereby being in a FREE-OPEN (FREE-OPEN) state.

Here, since the switching of the spool sp1V to the signal-on state by the speed control valve NC1V is delayed with respect to the signal-on of the OP-IN port, the rotation operation of the movable valve portion 40, that is, the movement of the piston 112 from the retracted position Pb is delayed with respect to the pressurization of the annular cylinder 80. Therefore, the operation procedure of performing the rotation operation of the rotary shaft 20 after the reduction operation of the thickness direction dimension of the movable valve portion 40, that is, after the thickness reduction operation of the movable valve portion 40 is completed, can be maintained.

At this time, the speed control valve NC3V reduces the pressure reduction of the output point main-CL because the direction from the output point main-CL to the atmosphere side is reversed. Thereby, air fed in advance as damping air remains in the contracting pressure space 22 c. Therefore, when the air is discharged to the atmosphere side through the inside of the communication groove 116, the space 22d, and the like by the buffer groove 119 and the control buffer flow passage 119a immediately after the valve opening operation is completed, the air damping effect and the air cushion effect can be obtained, and the movement of the piston 112 to the extended position Pa can be smoothly changed.

Finally, the output point main-CL is depressurized to a low pressure PLo state, which is the same as atmospheric pressure.

In this manner, when the opening operation of the slide valve 1 is finished, the valve-opened free-open state is maintained as shown in fig. 17.

Finally, the output point main-CL is depressurized to a low pressure PLo state, which is the same as atmospheric pressure.

Further, the rotation speed in the opening operation of the slide valve 1 is regulated by the moving speed of the piston 112 in the rotation driving cylinder 110 from the contraction position Pb toward the expansion position Pa side.

Here, when the piston 112 is at the end of the closing operation at the valve-closing position E2 (fig. 1), the residual pressure in the expansion pressure space 113 causes an air cushion action to set a damping pressure state in advance, thereby preventing the inner surface of the cylinder body 111 from coming into hard contact with the piston 112 and striking the piston, and preventing particles from being generated by the striking.

Further, at the time of moving the piston 112, the air cushion action by the effect of the air cushion packing in the space 22d corresponding to the connecting portion 112d can alleviate the speed at the time when the piston reaches the extended position Pa by functioning like the air damper described as the buffer groove 119, and can prevent the generation of particles due to the impact.

Next, the operation from the on state to the off state will be described.

At the timing when the valve-closing command as the closing operation command is turned on, that is, at the timing when the pressurized state IN the OP-IN port disappears and the low pressure PLo state almost equal to the atmospheric pressure is achieved without supplying the compressed air, as shown IN fig. 18, the output point FR connected to the OP-IN port and the pneumatic sp1V0 side of the spool sp1V become the low pressure PLo state as the pressure state.

At this time, the output point FR communicates with the OP-IN port equal to the atmospheric pressure, but the flow from the output point FR is smoothly depressurized IN time because the direction from the output point FR to the OP-IN port is the forward direction IN the speed control valve NC 1V.

At the same time, the spool sp1V moves leftward in fig. 18 by the biasing force of the spring, and is switched to the signal-off state in time.

Meanwhile, although the flow path on the output point main-OP side communicates with the OP-IN port equal to the atmospheric pressure, the direction from the output point main-OP to the OP-IN port side is reversed IN the speed control valve NC2V, and therefore the flow from the output point main-OP is delayed from the on switching of the valve close command.

Thereby, the flow passage on the output point main-OP side is communicated to the atmosphere (outside), and the extension pressure space 113 of the rotary drive cylinder 110 connected to the output point main-OP is depressurized. Then, the piston 112 starts moving from the extension position Pa toward the contraction position Pb by the urging force of the spring member 120s in the urging portion 120.

If the pneumatic sp1V0 side is in the low pressure PLo state, the output point FR is also in the low pressure PLo state.

Here, since the speed control needle valve and the check valve are connected IN parallel to the speed control valve NC1V, the pressure drop at the OP-IN port does not delay and involves the pressure drop on the pneumatic sp1V0 side and the output point FR. That is, although a delay is required in the free operation, the delay is not caused in the CLOSE state, and thus the delay function is not exerted.

At the same time, the flow path on the output point main-OP side is depressurized to a low pressure PLo state, and the depressurization is performed.

As the piston 112 moves from the extended position Pa toward the retracted position Pb, the rotary shaft 20 and the movable valve portion 40 rotate, and the movable valve portion 40 rotates from the retracted position E1 (fig. 1) toward the valve closing position (closing release position) E2 (fig. 1), and becomes a FREE-closed (FREE-CLOSE) state.

The annular cylinder 80 is depressurized to a low pressure PLo. Thereby, the thickness of the movable valve portion 40 is increased by the biasing force of the main spring 70, and the movable valve portion is operated to the closed state at the valve closing position E2 (fig. 1), and becomes the LOCK-closed (LOCK-CLOSE) state.

When the closing operation of the slide valve 1 is completed in this manner, the closed state can be maintained at the valve-closing position by the biasing force of the spring member 120s in the biasing portion 120, as shown in fig. 14.

Here, if the OP-IN port is IN the depressurized state, the dimension of the movable valve portion 40 IN the thickness direction can be maintained IN a state where it does not decrease, and therefore the slide valve 1 can be normally closed without performing an opening operation and without supplying driving pressure air.

The states in the sequence loop SQ described above are summarized.

< valve open State >

l main-OP: high voltage on state

l main-CL: atmospheric conduction state

lFR: high voltage on state

< in valve-closing rotation operation >

l main-OP: atmospheric release

l main-CL: high voltage on state

1 FR: high pressure holding state

< end of valve closing rotation, beginning of valve lifting operation >

l main-OP: atmospheric release

l main-CL: high voltage on state

lFR: atmospheric release

As described above, the pressure state and the valve opening/closing operation can be controlled at the output points of FR, main-OP, and main-CL with respect to the input of one system of the OP-IN port without using an electric mechanism. Further, by setting the order of change of the pressure states, the states of the closed position, the closing release position, and the retracted position are realized in order, and the slide valve 1 can be operated quickly and safely and the normally closed operation can be performed.

As described above, in the present embodiment, the movable valve portion 40 including the movable valve plate portion 50 and the movable valve frame portion 60 that can be separated from and brought close to each other in the flow channel direction is provided. The movable valve portion 40 is provided with a main spring 70 that biases the movable valve piece portion 50 and the movable valve frame portion 60 outward in the flow path direction, the movable valve portion 40 is provided with an annular cylinder 80 that moves the movable valve piece portion 50 and the movable valve frame portion 60 toward the center position side in the flow path direction of the hollow portion 11, and an auxiliary spring 90 that biases the movable valve frame portion 60 in a direction approaching the neutral valve portion 30. This allows the movable valve piece 50 and the movable valve frame 60 to be pressed against the inner surfaces 15a and 15b of the valve housing, and the valve can be reliably closed by the seal 61 and the reaction force transmission portion 59.

Further, by moving the movable valve piece portion 50 and the movable valve frame portion 60 toward the center position in the flow path direction of the hollow portion 11, the movable valve body 40 is rotated without contacting the valve housing 10, and the movable valve body 40 can be moved to the retreat position by a small-sized driving mechanism with a small output as compared with a mechanism requiring an operation other than the rotation.

In this structure, the valve body can be formed by one movable valve portion 40 and three urging portions 70, 80, 90. Further, the movable valve portion 50 and the movable valve frame portion 60 can be directly pressed against the inner surface of the valve housing 10 by the restoring force of the main spring 70 disposed in the peripheral region of the movable valve portion 40, and the valve can be reliably closed. Similarly, the movable valve plate portion 50 and the movable valve frame portion 60 can be moved away from the inner surface of the valve box 10 by the action of the compressed air supplied to the annular cylinder 80 disposed in the peripheral region of the movable valve portion 40, and can be reliably opened to be rotatable. Therefore, in the first embodiment, a slide valve having a simple structure and capable of performing a blocking operation with high reliability can be realized.

[ fastening bolt (fastening member) 43]

Fig. 19 is an enlarged view showing a main part of a member located near the fastening member in the present embodiment.

As shown in fig. 19, the fastening bolt (fastening member) 43 has a tip portion 43a provided with a male screw on an outer peripheral surface. The tip end portion 43a is screwed into a screw hole 63a provided in the fastening screw-threaded portion 63 of the movable valve frame portion 60. The fastening bolt 43 is provided such that the axis of the fastening bolt 43 faces a direction parallel to the thickness direction of the movable valve body 40, i.e., the direction B1 or the direction B2 which is the moving direction of the movable valve piece portion 50 and the movable valve frame portion 60.

The central portion 43b of the fastening bolt 43 has substantially the same diameter as the distal portion 43a, and axially movably penetrates through a through hole 57b provided in a fastening screw-threaded portion 63 provided in the movable valve portion 50. The diameter of the central portion 43b is set smaller than that of the through hole 57b, and they do not contact each other even when they are relatively moved in the axial direction.

The base end portion 43c of the fastening bolt 43 is a bolt head and has a diameter larger than the diameters of the tip end portion 43a and the central portion 43 b. The abutment surface 43d of the tip portion 43a abuts against the abutment surface 57d of the fastening portion 57 on the outer side of the through hole 57b facing the tip portion 43a, and the flow path direction changing position of the fastening bolt 43 and the movable valve sheet portion 50 can be restricted.

The fastening bolt 43 is provided with a locking groove 43e at a position closer to the tip than the portion provided with the tip portion 43a of the male screw. A retaining ring (retaining member) 43f such as a spacer is fitted into the retaining groove 43 e. The movement of the fastening bolt 43 in the axial direction (flow passage direction) is restricted in the inner direction (downward direction in the figure) by the abutment of the retaining ring 43f against the outer surface 63f of the screw hole 63 a. The retainer ring 43 locks the fastening bolt 43 so as to prevent the fastening bolt 43 from coming off the movable valve frame portion 60 even when the fastening bolt 43 is rotated.

The retainer ring (locking member) 43f is not simply intended to prevent the fastening bolt (fastening member) 43 from coming off, but is intended to hold the fastening bolt 43 in place for a long period of time without loosening in the state where the movable valve portion 50 and the movable valve frame portion 60 are released from fastening. That is, since the retainer ring (locking member) 43f needs to stably bear the tightening axial force, it is preferable to apply an E-type retainer ring or a C-type retainer ring as the retainer ring 43 f. Further, depending on the type of the retainer, a retainer having a shape corresponding to the shape of the locking groove 43e may be used. Further, as the locking member, a pin-type locking member may be applied. In this case, the locking groove 43e may be fixed to a locking hole provided in the radial direction of the fastening bolt 43.

The fastening bolt 43 is set to have a long length to such an extent that the abutment surface 43d on the distal end portion 43a side does not abut against the abutment surface 57d on the outside of the through hole 57b in the fastening portion 57 opposed to the abutment surface 43d even when the thickness of the movable valve portion 40 is maximized in a state where the collar 43f abuts against the outer surface 63 f. When the thickness of the movable valve portion 40 is minimized, the position of the movable valve portion 50 and the movable valve frame portion 60 is regulated by the abutment surfaces 57g abutting against the opposing abutment surfaces 63g of the fastening screw 63 and the fastening screw 63. That is, the movable valve portion 50 is movable in the direction B1 to a position where the abutment surface 57g abuts against the abutment surface 63g, and in the direction B2 to a position where the abutment surface 57d abuts against the abutment surface 43d, with respect to the fastening bolt 43 being screwed.

Therefore, by rotating the fastening bolt 43 with respect to the screw hole 63a to change the fastening length, the movable range of the movable valve portion 50, that is, the positions of the movable valve portion 50 and the movable valve frame portion 60 in the flow passage direction can be restricted. In particular, in a state where the cylinder 80 generates a force larger than the biasing force of the main spring 70 to reduce the thickness of the movable valve portion 40, the fastening bolt is rotated to bring the abutment surface 57d into abutment with the abutment surface 43 d. This can maintain the thickness of the movable valve portion 40 reduced even when the driving of the air cylinder 80 is stopped. This enables the neutral valve body 5 to be freely rotated without contacting the valve housing 10 during maintenance or the like.

In order to stably maintain the state in which the thickness of the movable valve portion 40 is reduced by the force generated by the cylinder being larger than the biasing force of the plurality of main springs 70, the fastening bolts 43 are arranged symmetrically with respect to the center positions where the plurality of main springs 70 are arranged, along the flow path direction of the movable valve portion 40 in a plan view.

Specifically, the shape of the movable valve portion 40 is substantially circular in a plan view in the flow path direction, and a plurality of main springs 70 are disposed concentrically in a first peripheral region 40a that is the outermost periphery of the movable valve portion 40. In this case, the plurality of fastening bolts 43 are arranged concentrically with respect to the arrangement of the plurality of main springs 70, and the number of fastening bolts 43 is set to be the same as the number of main springs 70 so that the intervals of the plurality of main springs 70 are equal to the intervals of the plurality of fastening bolts 43.

In the above configuration, the urging forces of the main springs 70 are completely equal to each other, for example. On the other hand, when the biasing forces of the plurality of main springs are unequal, it is preferable to provide the fastening bolts so that the unequal biasing forces are effectively received and the reduction width of the thickness dimension of the movable valve portion 40 is the same in the entire surface direction of the neutral valve body.

This eliminates the need to separately prepare a jig for reducing the thickness of the movable valve portion 40 for the movable valve portion 40 that constantly acts on the biasing force of the main spring 70, and enables the neutral valve body formed by the neutral valve portion 30 and the movable valve portion 40 to be removed.

Further, by providing the retaining ring 43f, the risk of loss after the fastening bolt 43 is removed at the time of maintenance can be eliminated.

Next, a gate valve according to a second embodiment of the present invention will be described with reference to the drawings.

Fig. 20 is a plan view showing a gate valve structure according to the present embodiment. Fig. 21 is a vertical cross-sectional view showing the structure of the gate valve according to the present embodiment, and is a view showing a case where the valve body is disposed at a position (FREE) where the retracting operation is possible. FIG. 21 corresponds to line B-O-C in FIG. 20.

Fig. 22 to 25 are views showing a case where the valve body is disposed at a position (FREE) where the retraction operation is possible, as in fig. 21. Fig. 22 is an enlarged view of a main portion along line a-O in fig. 20, and is a view showing a configuration of a member located in the vicinity of an a biasing portion incorporated in a valve housing. Fig. 23 is an enlarged view of a main portion along a line B-O in fig. 20, and is a view showing a configuration of a member located in the vicinity of a B biasing portion disposed between an a movable valve portion and a B movable valve portion. Fig. 24 is an enlarged view of a main portion along a line C-O in fig. 20, and is a view showing the a movable valve portion and the B movable valve portion at positions where the a biasing portion and the B biasing portion are not present. Fig. 25 is an enlarged view showing a main part of the C biasing portion in fig. 20. Fig. 21 is a view of the C biasing portion as viewed in the depth direction of the paper. Fig. 26 is a vertical sectional view showing the gate valve structure of the present embodiment, and is a view showing a case where the valve body is disposed at the valve closing position (no positive pressure or differential pressure). FIG. 26 corresponds to line B-O-C in FIG. 20.

[ pendulum type gate valve ]

As shown in fig. 20 to 25, the gate valve 300 of the present embodiment is a pendulum type slide valve.

The gate valve 300 includes: a valve housing 310 having a hollow portion 311, and a first opening 312a and a second opening 312b, the first opening 312a and the second opening 312b being provided opposite to each other with the hollow portion 311 interposed therebetween and forming a communicating flow path; and a neutral valve body 305 disposed in the hollow portion 311 of the valve housing 310 and capable of closing the first opening 312.

A flow passage H is defined from the first opening 312a toward the second opening 312 b. In the following description, the direction along the flow channel H is sometimes referred to as a flow channel direction H.

The gate valve 300 functions as a position switching unit that operates between a valve closing position (fig. 26) at which the neutral valve body 305 is in a closed state with respect to the first opening 312a, and a valve opening position at which the neutral valve body 305 is in an open state (fig. 21) in which the neutral valve body 305 is retracted from the first opening 312 a. In addition, the gate valve 300 has a rotary shaft 320, and the rotary shaft 320 has an axis extending in the flow path direction H.

The neutral valve body 305 is configured by a neutral valve portion 330 connected to the position switching portion (the neutral valve body 305) and a movable valve portion 340 connected to the neutral valve portion 330 so that the position in the flow path direction H can be changed.

The movable valve portion 340 includes an a movable valve portion 360 (movable valve frame portion) and a B movable valve portion 350 (movable valve piece portion). The a movable valve portion 360 (movable valve frame portion) is provided with a first seal portion 361, and the first seal portion 361 is provided around the a movable valve portion and is in close contact with the inner surface of the valve housing 310 located around the first opening portion 312 a.

The B movable valve portion 350 (movable valve portion) is slidable in the flow passage direction H with respect to the a movable valve portion 360 (movable valve frame portion).

The valve housing 310 incorporates a plurality of a biasing portions 370 (pistons: equivalent to the conventional main springs). The a urging portion 370 disposed inside the valve housing 310 configures a retractable elevating mechanism that urges the a movable valve portion 360 in a direction toward the sealing surface. The a biasing unit 370 is connected to and driven by the output point master-FR of the sequence circuit SQ in the first embodiment.

Thus, the a urging portion 370 has the following functions: that is, the a biasing portion 370 can bias the a movable valve portion 360 toward the first opening 312a in the flow path direction H so that the first seal portion 361 is brought into close contact with the inner surface of the valve housing 310 located around the first opening 312 a.

The gate valve of the present embodiment further includes a C biasing portion that is connected to the movable valve portion a so as to be able to change the position of the movable valve portion a in the flow path direction with respect to the neutral valve portion, and biases the movable valve portion a toward the center position in the flow path direction.

The gate valve of the present embodiment further includes an a biasing portion constituting the telescopic elevating mechanism in the valve housing, and the a biasing portion presses the a movable valve portion in a direction toward the sealing surface of the valve housing inner surface 310A.

According to this configuration, the valve body is constructed by the two movable valve portions, i.e., the a movable valve portion and the B movable valve portion, and the one B biasing portion, and the other a biasing portion is incorporated in the valve housing. In the gate valve according to the embodiment of the present invention, the biasing portion a functions when the valve-open state (fig. 21) is changed to the valve-closed state (fig. 26), and the biasing portion C functions when the valve-closed state (fig. 26) is changed to the valve-open state (fig. 21).

A B biasing portion (spring: equivalent to the previous cylinder) is disposed between the a movable valve portion 360 (movable valve frame portion) and the B movable valve portion 350 (movable valve piece portion) (built in the movable valve portion). The B urging portion is driven so that the thickness dimensions of the a movable valve portion 360 (movable valve frame portion) and the B movable valve portion (movable valve plate portion) in the flow passage direction H can be adjusted.

When the rotary shaft 320 rotates in the direction indicated by the reference symbol R1 (the direction intersecting the direction of the flow path H), the neutral valve portion 330 fixed to the rotary shaft 320 by a connecting member (not shown) also rotates in the direction R1 in accordance with the rotation. Further, since the movable valve portion 340 is slidably connected to the neutral valve portion 330 only in the thickness direction, the movable valve portion 340 and the neutral valve portion 330 rotate integrally.

By the rotation of the neutral valve portion 330 in this manner, the movable valve portion 40 moves in a pendulum motion from the retracted position located in the hollow portion 311 where the flow path H is not provided to the valve-closed position of the flow path H located at the position corresponding to the first opening 312 a.

The a biasing unit 370 incorporated in the valve box 310 operates by the compressed air supplied from the master-FR at the output point of the sequence circuit SQ in the first embodiment disposed inside the valve box 310. The a biasing portion 370 is configured by a drivable fixed portion (cylinder) 371, a movable portion (piston) 372 that is extendable and retractable from the fixed portion 371 in a direction toward the a movable valve portion 360 via the fixed portion 371, and a biasing member such as a spring that is disposed in the fixed portion 371 and biases the piston 372 toward the valve-closing side.

An annular seal member (O-ring) 75 is provided at a position on the distal end side of the movable portion 372 around the movable portion 372. The movable portion 372 is extendable and retractable in a state where the fixed side 371 and the vacuum side, which is the a movable valve portion 360 side, are sealed.

Thus, the a urging portion 370 has the following functions: that is, the distal end portion of the a urging portion 370 is brought into contact with the a movable valve portion 360 by the compressed air, whereby the a movable valve portion 360 is moved toward the first opening 312 a. The a biasing part 370 can be sealed by a spring force and can be FREE (FREE) (unsealed) by compressed air, as in the cylinder 80 and the main spring 70 of the first embodiment.

The a urging portion 370 brings the a movable valve portion 360 into contact with the inner surface of the valve housing 310 by the function of moving the a movable valve portion 360 toward the first opening portion 312a, and presses the a movable valve portion 360 against the inner surface of the valve housing 310 to close the flow passage H (valve closing operation).

On the other hand, the C urging portion 390 has a function of allowing the a movable valve portion 360 to be separated from the first opening 312 a. The C urging portion 390, taking advantage of this function, retracts the a movable valve portion 360 after pulling the a movable valve portion 360 away from the inner surface of the valve housing 310 to open the flow path H (releasing operation).

The valve closing operation and the releasing operation can be performed by the mechanical abutting operation of the a urging portion 370 that causes the a movable valve portion 360 to abut the inner surface of the valve housing 310 and the mechanical separating operation that separates the C urging portion 390 of the a movable valve portion 360 from the inner surface of the valve housing 310.

After the releasing operation, when the rotary shaft 320 is rotated in the direction indicated by the reference numeral R2 (retracting operation), the neutral valve portion 330 and the movable valve portion 340 (i.e., the a movable valve portion 360 and the B movable valve portion 350) also rotate in the direction R2 in accordance with the rotation.

Further, a B urging portion that is driven so that the thickness dimensions of the a movable valve portion 360 and the B movable valve portion 350 in the flow path direction H can be adjusted is disposed between the a movable valve portion and the B movable valve portion. That is, the B biasing portion is incorporated in the movable valve portion. Due to the presence of the B urging portion, the a movable valve portion and the B movable valve portion are interlocked in a series of operations (valve closing operation, releasing operation, retracting operation).

By the releasing operation and the retracting operation, the movable valve portion 340 performs a valve opening operation for retracting from the valve opening/closing position to the retracted position to be in a valve opening state.

In this way, the gate valve according to the present embodiment can have the following structure: that is, the valve body is configured by two valve portions, i.e., the a movable valve portion 360 and the B movable valve portion 350, and two biasing portions, i.e., the B biasing portion 380 and the C biasing portion 390, and the other a biasing portion is incorporated in the valve housing. That is, in the present embodiment, the weight of the valve body can be reduced in accordance with the case where the other a biasing portion is incorporated in the valve housing.

Therefore, according to the present embodiment, a gate valve can be provided as follows: the gate valve can perform a highly reliable blocking operation, and can realize a back pressure cancellation rate of 100% while achieving a reduction in weight of the movable valve portion.

[ valve box 310]

The valve housing 310 is constructed of a frame having a hollow portion 311. In fig. 21, a first opening 312a is provided on the upper surface of the frame, and a second opening 312b is provided on the lower surface of the frame.

The gate valve 300 is inserted between a space (first space) where the first opening 312a is exposed and a space (second space) where the second opening 312b is exposed. The gate valve 300 is configured to close (close) a flow path H connecting the first opening 312a and the second opening 312b, that is, a flow path H connecting the first space and the second space, and to open the closed state (connecting the first space and the second space).

The hollow portion 311 of the valve housing 310 is provided with a rotation shaft 320, a neutral valve portion 330, two valve portions of an a movable valve portion 360 (slide valve plate) and a B movable valve portion 350 (counter plate) constituting the movable valve portion 340, and two urging portions of a B urging portion 380 (holding spring) and a C urging portion 390 (auxiliary spring). An a urging portion (elevating mechanism) is provided inside a frame configuring the valve housing 310.

[ rotating shaft 320]

The rotary shaft 320 corresponds to the rotary shaft 20 of the first embodiment, and is provided to extend in a state substantially parallel to the flow passage H, penetrate the valve housing 10, and be rotatable. The rotary shaft 20 can be rotated by the rotary drive mechanism 100 of the first embodiment and the sequence circuit SQ connected thereto.

A coupling member (not shown) is fixed to the rotary shaft 320. The connecting member is, for example, a substantially flat plate-like member, and is fixed to one end of the rotary shaft 320 by a bolt or the like.

[ neutral valve section 330]

The neutral valve portion 330 is disposed to extend in a direction orthogonal to the axis of the rotary shaft 320, and is included in a plane parallel to the orthogonal direction. The neutral valve portion 330 is fixed to the rotary shaft 320 by a connecting member (not shown) or directly fixed to the rotary shaft 320 without a connecting member (not shown).

As shown in fig. 20, the neutral valve portion 330 includes a circular portion 330a overlapping the movable valve portion 340, and a rotating portion 330b that rotates the circular portion 330a with the rotation of the rotating shaft 320. The rotation portion 330b is located between the rotation shaft 320 and the circular portion 330a, and is formed in an arm shape in which two levers extend from the rotation shaft 320 toward the circular portion 330 a. Thus, the circular portion 330a is sometimes referred to as an arm portion.

The rotary shaft 20 and the neutral valve portion 330 are provided so as not to be positionally displaced in the flow path H direction although they are rotated relative to the valve housing 310.

The rotation shaft 320 can be selectively connected to either one of the upper side and the lower side of the neutral valve portion 330 in the flow path direction H. Alternatively, the rotary shaft 320 may be attached to both surfaces of the neutral valve body 305 as a whole, that is, the neutral valve body 305.

In the present embodiment, the following will be explained: that is, when the gate valve is closed, the gate valve is opened and closed based on the arrangement of the gate valve in which the neutral valve body 305 moves so that the movable valve part 340 blocks the first opening 312 a.

[ Movable valve portion 340, B movable valve portion 350 (movable valve plate portion: counter plate), A movable valve portion 360 (movable valve frame portion: sliding valve plate) ]

The movable valve portion 340 has a substantially circular plate shape, and includes a B movable valve portion 350 formed substantially concentrically with the circular portion 330a, and a substantially annular a movable valve portion 360 disposed so as to surround the B movable valve portion 350. The a movable valve portion 360 is connected to the neutral valve portion 330 so as to be slidable in the flow path H direction. The B movable valve portion 350 is slidably fitted to the a movable valve portion 360.

The B movable valve portion 350 and the a movable valve portion 360 can be moved while being slid in the directions (reciprocating directions) indicated by the reference numerals B1, B2 (fig. 21) by the B urging portion 380 (holding spring). Here, the directions indicated by reference numerals B1, B2 are directions perpendicular to the surfaces of the B movable valve portion 350 and the a movable valve portion 360, and are flow passage H directions parallel to the axial direction of the rotary shaft 320.

In addition, an inner peripheral crank portion 350c is formed in the entire region near the outer periphery of the B movable valve portion 350. In addition, an outer peripheral crank portion 360c is formed in the entire region near the inner periphery of the a movable valve portion 360.

In the present embodiment, the outer circumferential crank portion 360c has a sliding surface 360b parallel to the flow passage H direction. The inner peripheral crank portion 350c has a sliding surface 50b parallel to the flow passage H direction.

Outer circumferential crank portion 360c and inner circumferential crank portion 350c are fitted so that sliding surfaces 350b and 360b can slide on each other. To enable this sliding, a third seal portion 352 (sliding seal gasket) formed of an O-ring or the like is disposed between the outer circumferential crank portion 360c and the inner circumferential crank portion 350 c.

A first seal portion 361 (a sheet seal) is provided on a surface of the a movable valve portion 360 that faces (abuts) an inner surface of the valve housing 310, and the first seal portion 361 is formed into an annular shape corresponding to the shape of the first opening 312a, for example, by an O-ring or the like.

The first seal portion 361 is in contact with the valve housing inner surface 310A of the valve housing 310, which is the peripheral edge of the first opening portion 312a, in a state where the first opening portion 312a is covered with the movable valve portion 340 at the time of valve closing, and is pressed by the a movable valve portion 360 and the valve housing inner surface 310A of the valve housing 310. Thereby, the first space is surely isolated from the second space (the blocked state is ensured).

A second sealing portion 351 (facing pad) is provided on a surface of the B movable valve portion 350 facing (abutting) the valve box inner surface 310A of the valve box 310, and the second sealing portion 351 is formed in an annular shape corresponding to the shape of the second opening portion 312B and is formed by, for example, an O-ring or the like.

[ B urging part 380 (holding spring) ]

The B urging portion 380 (holding spring) is located between the a movable valve portion and the B movable valve portion, and is partially disposed in a region where the a movable valve portion 360 and the B movable valve portion 350 overlap. That is, the B urging portion 380 is incorporated in the movable valve portion 340 (between the a movable valve portion 360 and the B movable valve portion 350). The B biasing portions 380 are preferably provided at three or more locations spaced apart from each other. The arrangement of the B biasing portions 380 spaced apart from each other is not limited to the arrangement at equal intervals, and a plurality of B biasing portions 380 may be arranged at unequal intervals. Fig. 20 shows a configuration example in which three B biasing portions 380 are arranged at the same angular position (120 degrees) when viewed from the center O of the valve body.

The B urging portion 380 is configured to guide (restrict) the movement of the B movable valve portion by the long shaft portion of a bolt-like guide pin 381 fixed to the a movable valve portion 360 (movable valve frame portion: sliding valve plate). The holding spring of the configuration B urging portion 380 is formed of an elastic member (e.g., a spring, rubber, or the like).

The B urging portion 380 (holding spring) is driven so that the thickness dimensions of the a movable valve portion 360 and the B movable valve portion 350 in the flow path direction H can be adjusted. Thereby, the B movable valve portion 350 is interlocked in the direction in which the a movable valve portion 360 moves (the direction of reference character B1 or the direction of reference character B2).

At this time, since the B movable valve portion 50 is driven so that the thickness dimension in the flow path direction H can be adjusted, the impact of the gate valve generated when the first seal portion 361 of the a movable valve portion 360 comes into contact with the valve box inner surface 310A of the valve box 310 is alleviated at the time of the above-described valve closing.

Further, when the valve is opened or when the back pressure is applied, the impact of the gate valve generated when the second sealing portion 351 of the B movable valve portion 350 contacts the valve housing inner surface 310B of the valve housing 310 is alleviated. Upon receiving the impact, a closed space is formed by the B movable valve portion 350, the valve housing inner surface 310B, and the second seal portion 351. In order to remove the gas that applies pressure to the closed space, the B movable valve portion 350 is provided with a gas discharge hole 353.

[ guide pin 81]

The guide pin 381 is fixedly provided to the a movable valve portion 360 and is erected in the flow path direction H, and is configured of a rod-shaped body having a uniform thickness dimension. The guide pin 381 penetrates the B biasing portion 380 and is fitted into the hole 50h formed in the B movable valve portion 350.

The guide pins 381 securely guide the position restriction of the B and a movable valve portions 350 and 360 such that the direction in which the B and a movable valve portions 350 and 360 slide (the axis indicated by the reference symbol Q) does not deviate from the directions indicated by the reference symbols B1 and B2. When the B and a movable valve portions 350 and 360 slide, the guide pins 381 also reliably guide the position restriction of the B and a movable valve portions 350 and 360 so that the B and a movable valve portions 350 and 360 move in parallel without changing their postures.

[ C urging part 390 (auxiliary spring) ]

The C urging portion 390 (assist spring) is provided between the neutral valve portion 330 and the a movable valve portion 360. The C biasing portion 390 connects the a movable valve portion 360 to the neutral valve portion 330 so that the position in the flow path direction can be changed in the flow path direction H of the valve housing 310, and biases the a movable valve portion toward the center position in the flow path direction. Thus, in the present embodiment, the C biasing portion 390 functions when the gate valve is changed from the closed state (fig. 26) to the open state (fig. 21). That is, the C urging portion 390 has a structure for promoting, from the valve-closed state (fig. 26), a mechanical separation operation of pulling the a movable valve portion 360 away from the inner surface of the valve housing 310.

The C urging portion 390 is provided at a position (position regulating portion 365) overlapping the circular portion 330a, the position having the circular portion 330a positioned at the outer peripheral position of the neutral valve portion 330 and being positioned at the outer peripheral position of the a movable valve portion 360.

The C biasing portion 390 is disposed at the same angular position as the B biasing portion 380 when viewed from the center O of the valve body. Fig. 20 shows a configuration example in which three C biasing portions 390 are arranged.

The C biasing portion 390 is also an elastic member (for example, a spring, rubber, or leaf spring) as in the B biasing portion 380.

Among these, in particular, when a plate spring (fig. 21) is used as the C biasing portion 390, it is more preferable to provide a function α of pulling in and holding the a movable valve portion 360 toward the neutral valve portion 330 (arm) [ a function of promoting the mechanical separation operation from the valve-closed state (fig. 26) ], and a function β of holding a radial position of the a movable valve portion 360 with respect to the neutral valve portion 330 (arm).

Fig. 25 is a schematic cross-sectional view showing the C biasing portion 390 when the gate valve is in the open state (fig. 21).

As shown in fig. 21, portions close to both ends of the plate spring (C biasing portion 390) are engaged with the fixing pins 392, 393 via the ring members 392a, 392b in the circumferential direction of the circular portion 330a of the neutral valve portion 330. Further, a portion of the plate spring near the center is coupled to the position regulating portion 365 of the a movable valve portion 360 by a pressing pin 391 (printing).

The plate spring in which the gate valve is in the open state (fig. 21) has the curved portion 390A, and thus a is in a state where the distance in the height direction is reduced, that is, a state where the movable valve portion 360 is spaced apart from the neutral valve portion 330 (arm) by a small distance (fig. 25).

In contrast, in the leaf spring when the gate valve is in the valve-closed state (fig. 26), the distance in the height direction is increased by eliminating the curved portion 390A shown in fig. 25, that is, the distance between the a movable valve portion 360 and the neutral valve portion 330 (arm) is increased.

As described above, by employing a plate spring having an extremely simple structure as the C biasing portion 390, the C biasing portion 390 in the gate valve according to the embodiment of the present invention can stably obtain the above-described two functions (function α and function β).

[ A forcing part 370 (elevating mechanism) ]

The a biasing portion 370 (elevating mechanism) is built in the valve housing, and is configured to be independent from the valve body including the two valve portions of the a movable valve portion and the B movable valve portion and the two biasing portions of the B biasing portion and the C biasing portion.

The a biasing unit 70 extends the distal end portion of the movable unit 372 toward the a movable valve unit 360 by the pressure applied to the fixed unit 371 by the output point master-FR of the sequence circuit SQ in the first embodiment. By this operation, the a movable valve portion 360 is urged in the flow path direction H toward the first opening 312 a. The a urging portion 370 has the following functions: that is, the first seal portion 361 can be brought into close contact with the valve box inner surface 310A around the first opening 312a by the extension operation of the movable portion 372.

The extending operation of the movable portion 372 can be operated substantially simultaneously in each of the plurality of a urging portions 370 built in the valve housing 310.

The a biasing portion 370 does not have a reverse function of separating the first seal portion 361 from the valve housing inner surface 310A around the first opening portion 312a, but has a function of returning itself (movable portion 372 described later) to an initial movement position (position in the fixed portion 371 described later). Therefore, the a biasing portion 370 is a lifting mechanism that can be extended and contracted from the a biasing portion 370 in a direction toward the a movable valve portion 360.

The a urging portions 370 having such a configuration are arranged at positions acting on the a movable valve portion 360 in the valve housing 310 and are provided along the a movable valve portion 360.

In the configuration example shown in fig. 20, the a biasing portions 370 are preferably provided at three or more locations spaced apart from each other.

The arrangement of the a biasing portions 370 spaced apart from each other is not limited to the arrangement at equal intervals, and a plurality of a biasing portions 370 may be arranged at unequal intervals. Fig. 20 shows a configuration example in which four a biasing portions 370 are arranged at the same angular position (90 degrees) when viewed from the center O of the valve body.

The a biasing portion 370 in this configuration example is configured such that the angular position of the a biasing portion 370 does not overlap the angular position at which the B biasing portion 80 and the C biasing portion described above are arranged.

According to this configuration, the a urging portion 370 has both a function of moving the a movable valve portion 360 toward the first opening 312 by bringing the distal end portion 372a of the movable portion 372 into contact with the lower surface 360sb of the a movable valve portion 360 and a function of returning itself (the movable portion 372) to the initial movement position (the position in the fixed portion 371), and plays a role of a valve body lifting mechanism.

Fig. 21 to 24 show a state in which the movable valve portion 340 (the a movable valve portion 360 and the B movable valve portion 350) is not in contact with any of the valve housing inner surfaces 310A and 310B of the valve housing 310. This state is referred to as a free state of the valve body. Fig. 6 is an enlarged view of a main part of the C biasing portion in a free state (fig. 21), and is a view of the C biasing portion as viewed from the depth direction of the paper surface in fig. 21.

In the free state of the valve body, the movable valve portion 360 is moved until it comes into contact with the valve housing inner surface 310A of the valve housing 310 by the function of the above-described a urging portion 370, that is, by the function of moving the movable valve portion 360 toward the first opening 312a, and the movable valve portion 360 is pressed against the valve housing inner surface 310A, whereby the flow passage H is closed (valve closing operation).

Fig. 26 shows a state where the flow passage H is closed by the valve closing operation. This state is referred to as a state without a positive pressure/differential pressure.

In a state where the valve body is not under the positive pressure/differential pressure, the above-described function of the C biasing portion 390, that is, the function of connecting the a movable valve portion 360 to the neutral valve portion 330 so as to be able to change the position in the flow path direction and biasing the a movable valve portion toward the center position in the flow path direction, pulls the a movable valve portion 360 away from the inner surface of the valve housing 310 to retract the a movable valve portion 360, thereby opening the flow path H (releasing operation).

The a biasing portion 370 in the gate valve of the present embodiment is incorporated in the valve housing 310, and is configured independently of the neutral valve body 305 including the two valve portions, i.e., the a movable valve portion 360 and the B movable valve portion 350, and the two biasing portions, i.e., the B biasing portion 380 and the C biasing portion 390, and is driven by the rotation driving mechanism 100 and the sequence circuit SQ connected thereto in the first embodiment. Thus, the gate valve 300 of the present embodiment can reduce the weight of the valve body structure in accordance with the weight of the a biasing portion 370.

In the present embodiment, the same effects as those of the first embodiment can be obtained.

Next, a third embodiment of the gate valve according to the present invention will be described with reference to the drawings.

Fig. 27 is a sectional view showing a gate valve according to the present embodiment.

The present embodiment is different from the first and second embodiments described above in the point relating to the seal ring and the points attached thereto.

The gate valve 500 of the present embodiment is a pendulum type slide valve.

As shown in fig. 27, the gate valve 500 includes: a valve box 510 having a hollow portion 511, and a first opening portion 512a and a second opening portion 512b, the first opening portion 512a and the second opening portion 512b being provided opposite to each other with the hollow portion 511 therebetween and forming a communicating flow path; a neutral valve body (valve body) 505 which is disposed in the hollow portion 511 of the valve box 510 and can close the first opening portion 512 a; a rotary shaft 520 that functions as a position switching unit that operates the valve body 505 between a valve closing position at which the valve body 505 is in a closed state with respect to the first opening 512a and a valve opening position at which the valve body 505 is in an open state retracted from the first opening 512a, and that has an axis extending in the flow passage direction; a rotary shaft drive mechanism (rotary device) 600 including a rack member 522 and a pinion gear 521 for rotating a rotary shaft 520, and a rotary cylinder 610 for driving them; a seal 540 slidably provided around the first opening 512a in the flow path direction H, the seal 540 being capable of achieving a closed state in which the flow path is closed by being brought into contact with the valve body 505 that is in the valve closed position, and an open state in which the valve body 505 is openable toward the valve open position; a closing release cylinder 570 built in the valve box 510 for releasing the closed state of the packing 540; a seal ring biasing portion 590 biasing the seal ring 540 in a direction of abutting against the valve body 505; and a sequence circuit SQ that can sequentially perform an operation of releasing the closing of the valve body 505 and an operation of rotating the valve body 505.

In the present embodiment, the hollow portion 511 corresponds to the hollow portion 11 of the first embodiment, the first opening portion 512a corresponds to the first opening portion 12a of the first embodiment, the second opening portion 512b corresponds to the second opening portion 12b of the first embodiment, the valve housing 510 corresponds to the valve housing 10 of the first embodiment, the rotary shaft 520 corresponds to the rotary shaft 20 of the first embodiment, the rack member 522 corresponds to the rack member 22 of the first embodiment, the pinion 521 corresponds to the pinion 21 of the first embodiment, the rotary shaft drive mechanism (rotary device) 600 corresponds to the rotary shaft drive mechanism (rotary device) 110 of the first embodiment, the rotary cylinder 610 corresponds to the rotary cylinder 610 of the first embodiment, and here, the number of hundreds (hundreds) of squares of reference numerals are replaced, the description thereof is omitted.

The valve body 505 of the present embodiment is a plate body that closes the flow passage while the thickness dimension thereof is unchanged, although the valve body is rotated about the rotation shaft 520.

The seal 540 of the present embodiment can be in a closed state in which the seal abuts on the valve body 505 that is in the valve closed position to close the flow passage and an open state in which the valve body 505 can be opened to the valve open position. The seal ring 540 includes: a cylindrical portion 541 provided in the valve box 510 so as to be slidable in the flow path direction H around the first opening 512 a; and a flange 542 provided around the outside of the cylindrical portion 541.

The flange portion 542 is provided on the outer side of the periphery as a position opposed to (abutting) the valve body 505. A first seal portion 542a (facing pad) is provided on a surface of the flange portion 542 facing (abutting) the valve body 505, and the first seal portion 542a is formed in an annular shape corresponding to the shape of the first opening portion 512a, and is formed by, for example, an O-ring or the like.

Similarly, the first opening 512a of the valve box 510 and a sealing portion 541a (facing pad) are provided on the outer periphery of the cylindrical portion 541, and the sealing portion 541a is formed in an arc shape when sliding, for example, by an O-ring or the like.

The closure release cylinder 570 is incorporated in the valve box 510, and a plurality of closure release cylinders 570 are provided at positions around the seal ring 540 at positions on the back surface of the first seal portion 542a with respect to the flange portion 542.

The closure release cylinder 570 has: an internal space 571 built in the valve box 510; a piston 573 slidably provided in the internal space 571; a movable part 572 connected to the piston 573 and having a tip end portion extending toward the seal 540; and a seal biasing portion 590 as a spring member provided in the internal space 571.

The closure release cylinder 570 operates in accordance with the biasing portion a (lifting mechanism) of the second embodiment described above. The movable part 572 performs an operation corresponding to the movable part 72. The internal space 570 is connected to the output point FR in the sequence circuit SQ of the first embodiment.

The seal biasing portion 590 biases the distal end portion of the movable portion 572 to extend toward the seal 540 in a state where there is no pressurization from the output point FR.

Further, the pressure in the internal space 571 is increased and the distal end portion of the movable portion 572 is retracted away from the seal 540 in a state pressurized by the output point FR.

The piston 573, the periphery of the internal space 571 and the movable part 572, and the closure releasing cylinder 570 are sealed so as to be maintained in a sealed state by a sealing member.

The rotary shaft drive mechanism (rotation device) 600 in the present embodiment corresponds to the rotary shaft drive mechanism 100 in the first embodiment. The rotary cylinder 610 has: a biasing portion 620 for causing the valve body 505 to perform a closing operation; a piston 612 slidable in an inner space 611b of the cylinder body (housing) 611 to be opened and closed; and a first pressure space 522c and a second pressure space 613, which are arranged in series in the operating direction of the piston 612 and enable the piston 612 to perform a closing operation, and enable the piston 612 to perform an opening operation.

The first pressure space 522c is connected to the output point main-CL in the sequential circuit SQ of the first embodiment, and the second pressure space 613 is connected to the output point main-OP in the sequential circuit SQ of the first embodiment.

The spring member 620s as the biasing portion 620 is provided in the internal space 611b of the cylinder body (housing) 611 at a position of the piston 612 close to the rack member 522, and biases the valve body 505 in a direction in which the rotary cylinder 610 retracts, that is, in a direction in which the valve body 505 is closed.

The configuration of the sequence circuit SQ in the present embodiment is the same as that of the sequence circuit SQ in the first embodiment. The sequence circuit SQ includes a pneumatic two-chamber spool valve sp1V and speed control valves NC1V, NC2V, and NC3V each including a combination of a check valve and a flow rate adjustment valve.

In the gate valve 500 of the present embodiment, the switching operation can be performed by performing the same sequence operation as the sequence circuit SQ in the first embodiment on the internal space 571 of the closure release cylinder 570 connected to the output point FR, the first pressure space 522c connected to the output point master-CL, and the second pressure space 613 connected to the output point master-OP.

This prevents the inner surface of the cylinder body 611 and the piston 612 from strongly abutting and impacting during the valve closing operation.

Industrial applicability:

the present invention can be widely applied to gate valves for the following purposes: in a vacuum apparatus or the like, the use is to switch between a state in which a flow path connecting two spaces having different properties such as vacuum degree, temperature, or gas atmosphere is blocked and a state in which the blocked state is opened; and the use of controlling the opening in the case of an open blocking state.

Description of the reference numerals

1 … gate valve

5 … neutral valve body

10. 10a, 10b … valve box

11 … hollow part

12a … first opening part

12b … second opening part

17. 18 … fluid path ring

20 … rotating shaft

21 … pinion

22 … rack

26 … valve shaft

30 … neutral valve portion

40 … movable valve portion

41 … supply path

42 … communication channel

50 … Movable valve part (second movable valve part)

51a, 51b … second seal

52a, 52b … third seal

53. 54 … wiper

55. 56 … middle atmospheric chamber

60 … Movable valve frame portion (first movable valve portion)

61 … first seal

62 … guide pin

68 … connecting pin

68A … floating pin

69 … connection pin part

70 … Main spring (first force application part)

80 … circular cylinder (second force application part)

90 … auxiliary spring (third force application part)

91 … connecting component

100 … rotary shaft driving mechanism

110 … rotary driving cylinder (cylinder body)

120 … force application part

120s … spring component

111 … Cylinder body

111b … inner space

112 … piston

122s … axle

113 … expansion pressure space (second pressure space)

22c … contracting pressure space (first pressure space)

114 … vent

118 … buffer tank

SQ … timing loop

FR, Master-OP, Master-CL … output Point

sp1V … slide valve

NC1V, NC2V and NC3V … speed regulating valve

cdS … Limit switch valve

Pa … extended position

E1 … retreat position

Pb … contracted position

E2 … valve open position