阅读说明：本技术 一种流量控制器 (Flow controller ) 是由 李春玉 苏乾益 杜井庆 张海洋 于 2021-08-27 设计创作，主要内容包括：本发明提供一种流量控制器,包括基座块和控流阀,基座块中开设有流体通道,流体通道包括进气段和出气段,控流阀包括阀芯、阀口、簧片和阀芯驱动组件,阀口中形成有出气道和多个进气孔,出气道与出气段连通,多个进气孔环绕出气道均匀分布且与进气段连通；簧片用于驱动阀芯沿靠近阀口方向运动,以使阀芯封闭出气道；阀芯驱动组件用于驱动阀芯沿远离阀口方向运动,以连通进气孔和出气道并控制进气孔和出气道之间的流通截面积。在本发明中,出气道周边的进气孔与流体通道的进气段连接,减小了簧片承受流体压力的力臂,从而有效减小了簧片所需承受的力矩,提高了簧片的稳定性,进而提高了流量控制器的控制精度和重复性。(The invention provides a flow controller, which comprises a base block and a flow control valve, wherein a fluid channel is arranged in the base block, the fluid channel comprises an air inlet section and an air outlet section, the flow control valve comprises a valve core, a valve port, a reed and a valve core driving assembly, an air outlet channel and a plurality of air inlet holes are formed in the valve port, the air outlet channel is communicated with the air outlet section, and the air inlet holes are uniformly distributed around the air outlet channel and are communicated with the air inlet section; the reed is used for driving the valve core to move along the direction close to the valve port so as to enable the valve core to seal the air outlet channel; the valve core driving assembly is used for driving the valve core to move along the direction far away from the valve port so as to communicate the air inlet hole and the air outlet channel and control the flow sectional area between the air inlet hole and the air outlet channel. In the invention, the air inlet holes on the periphery of the air outlet channel are connected with the air inlet section of the fluid channel, so that the force arm of the reed bearing the fluid pressure is reduced, the moment of force required to be borne by the reed is effectively reduced, the stability of the reed is improved, and the control precision and the repeatability of the flow controller are further improved.)

1. A flow controller is characterized by comprising a base block and a flow control valve, wherein a fluid channel is formed in the base block, the fluid channel comprises an air inlet section and an air outlet section, the flow control valve is arranged on the base block and used for selectively communicating the air inlet section with the air outlet section and controlling the flow cross-sectional area between the air inlet section and the air outlet section so as to control the flow of fluid, wherein,

the flow control valve comprises a valve core, a valve port, a reed and a valve core driving assembly, wherein an air outlet channel and a plurality of air inlet holes which extend in the same direction are formed in the valve port, the axis of the air outlet channel is overlapped with the axis of the valve port, the air outlet channel is communicated with the air outlet section, the plurality of air inlet holes are uniformly distributed around the air outlet channel, and the plurality of air inlet holes are communicated with the air inlet section; the reed is used for driving the valve core to move along the direction close to the valve port through elasticity, so that the valve core seals the air outlet channel; the valve core driving assembly is used for driving the valve core to move along the direction far away from the valve port so as to communicate the plurality of air inlet holes and the air outlet channel, and controlling the flow cross-sectional area between the plurality of air inlet holes and the air outlet channel by controlling the distance of the valve core far away from the valve port, thereby controlling the flow cross-sectional area between the air inlet section and the air outlet section.

2. The flow controller according to claim 1, wherein a cylindrical cavity is opened on the base block, the valve port and the valve core are both arranged coaxially with the cylindrical cavity, the valve port is arranged at the bottom of the cylindrical cavity, the outer side wall of the valve port is in sealing fit with the inner wall of the cylindrical cavity, and the valve core partially enters the cylindrical cavity from the top of the cylindrical cavity;

the air outlet section is communicated with the cylindrical cavity in the central area of the bottom wall of the cylindrical cavity and further communicated with the air outlet channel; the air inlet section is communicated with the cylindrical cavity in the edge area of the bottom wall of the cylindrical cavity, an annular communicating groove surrounding the air outlet channel is formed on the surface of one side of the valve port, which is far away from the valve core, and the air inlet section is communicated with the air inlet holes through the annular communicating groove.

3. The flow controller according to claim 2, wherein a center of a surface of the valve core on a side facing the valve port is formed with a blocking boss for blocking the gas outlet passage; the reed is annular, the reed is sleeved on the plugging boss through a central hole of the reed and is fixedly connected with the plugging boss, and the outer edge of the reed is fixedly arranged above the valve port;

a plurality of strip-shaped grooves penetrating through the reed along the thickness direction are formed in the reed, each strip-shaped groove comprises a first arc-shaped groove, a second arc-shaped groove and a transition groove, the first arc-shaped grooves and the second arc-shaped grooves circumferentially extend around the central hole, and the radian of each first arc-shaped groove is smaller than that of each second arc-shaped groove; the first arc-shaped groove and the second arc-shaped groove are circumferentially staggered, and the mutually close end parts of the first arc-shaped groove and the second arc-shaped groove are connected through the transition groove; the first arc-shaped groove in each strip-shaped groove is radially arranged at intervals with the second arc-shaped groove in the adjacent strip-shaped groove.

4. A flow controller according to claim 3 wherein three of said strip-shaped grooves are formed in said reed.

5. The flow controller according to claim 3 or 4, wherein a blind flow guide hole coaxial with the valve core is formed on the blocking boss of the valve core, a plurality of radial flow guide holes are formed on the side wall of the valve core, the blind flow guide hole is communicated with the plurality of radial flow guide holes, and the radial flow guide holes are communicated with the plurality of air inlet holes through the cylindrical cavity.

6. The flow controller according to claim 5, wherein two radial guide holes are formed in the valve core, the two radial guide holes are perpendicular to each other, and each radial guide hole is penetrated from one side wall to the other side wall of the valve core.

7. A flow controller according to claim 3 or 4, further comprising a spring, wherein the side of the valve element facing away from the valve port has a spring locating surface, one end of the spring faces and contacts the spring locating surface, and the other end of the spring is fixedly arranged.

8. The flow controller of claim 7, wherein said spring comprises a cylindrical body having a plurality of helical grooves formed therein extending through a sidewall of said cylindrical body and extending helically about an axis of said cylindrical body, said plurality of helical grooves being identical in shape and axial position on said cylindrical body, said plurality of helical grooves being spaced apart from one another.

9. The flow controller of claim 8, wherein the cylindrical body has two helical grooves formed therein, the helical grooves extending in a helical manner around the axis of the cylindrical body, and the two helical grooves are arranged symmetrically with respect to the axis of the cylindrical body.

10. The flow controller of claim 7, wherein the spring is made of stainless steel, hastelloy or spring steel.

Technical Field

The invention relates to the field of flow control, in particular to a flow controller.

Background

The gas flow controller is an instrument which is arranged on a gas path and is used for measuring and controlling the gas flow in the gas path in real time. Is one of the most important instruments in industrial measurement. In order to adapt to various purposes, various flow controllers come out in succession, and are widely applied to the fields of petroleum and natural gas, petrochemical industry, food and beverage, energy, metallurgy and the like. With the development of the industry and the gradual expansion of the use industry, the requirements of various fields, particularly the semiconductor field, on the gas flow controller are higher and higher, and higher precision and repeatability are required.

As shown in fig. 1, fig. 2 and 6 are O-shaped rubber sealing rings, gas enters a valve port 5 from an air inlet side, when the gas flow controller needs to be closed, a control circuit does not provide a signal for an armature 1, and a valve core 4 is pressed down under the action of the elastic force of a reed 3, so that a sealing rubber gasket arranged at the bottom of the valve core 4 seals a gas passage on the valve port 5. When the gas passes through, the control circuit gives a signal according to the gas quantity to be passed through, so that the armature 1 moves upwards under the driving of the voltage with the corresponding magnitude, the valve core 4 is driven to move upwards, and a channel is formed between the valve core 4 and the valve port 5. At the moment, the gas flows from the gas inlet side to the valve port 5 along the arrow direction, continues to pass through the channel between the valve port 5 and the valve core 4 and finally flows to the gas outlet side, the size of the channel formed between the valve core 4 and the valve port 5 determines the gas flow, and therefore the flow of the gas in the gas flow controller can be accurately controlled through the size of the voltage signal provided to the armature 1 by the control circuit.

However, the existing gas flow controller often has an internal leakage phenomenon, which means that the gas does not diffuse to the outside of the gas flow controller, but the gas does not travel according to a preset path and goes to a place inside the device where the gas should not go; or gas flow occurs when there is no time for gas to flow through, which can have a serious impact on the accuracy of the gas flow controller.

Therefore, how to provide a flow controller structure with higher stability becomes a technical problem to be solved in the field.

Disclosure of Invention

The invention aims to provide a flow controller which has high control precision and repeatability.

In order to achieve the above object, the present invention provides a flow controller, comprising a base block and a flow control valve, wherein a fluid channel is disposed in the base block, the fluid channel comprises an air inlet section and an air outlet section, the flow control valve is disposed on the base block and is configured to selectively communicate the air inlet section with the air outlet section and control a flow cross-sectional area between the air inlet section and the air outlet section, so as to control a fluid flow, wherein,

the flow control valve comprises a valve core, a valve port, a reed and a valve core driving assembly, wherein an air outlet channel and a plurality of air inlet holes which extend in the same direction are formed in the valve port, the axis of the air outlet channel is overlapped with the axis of the valve port, the air outlet channel is communicated with the air outlet section, the plurality of air inlet holes are uniformly distributed around the air outlet channel, and the plurality of air inlet holes are communicated with the air inlet section; the reed is used for driving the valve core to move along the direction close to the valve port through elasticity, so that the valve core seals the air outlet channel; the valve core driving assembly is used for driving the valve core to move along the direction far away from the valve port so as to communicate the plurality of air inlet holes and the air outlet channel, and controlling the flow cross-sectional area between the plurality of air inlet holes and the air outlet channel by controlling the distance of the valve core far away from the valve port, thereby controlling the flow cross-sectional area between the air inlet section and the air outlet section.

Optionally, a cylindrical cavity is formed in the base block, the valve port and the valve core are both arranged coaxially with the cylindrical cavity, the valve port is arranged at the bottom of the cylindrical cavity, the outer side wall of the valve port is in sealing fit with the inner wall of the cylindrical cavity, and the valve core part enters the cylindrical cavity from the top of the cylindrical cavity;

the air outlet section is communicated with the cylindrical cavity in the central area of the bottom wall of the cylindrical cavity and further communicated with the air outlet channel; the air inlet section is communicated with the cylindrical cavity in the edge area of the bottom wall of the cylindrical cavity, an annular communicating groove surrounding the air outlet channel is formed on the surface of one side of the valve port, which is far away from the valve core, and the air inlet section is communicated with the air inlet holes through the annular communicating groove.

Optionally, a blocking boss is formed in the center of the surface of the valve core on one side facing the valve port, and is used for blocking the air outlet channel; the reed is annular, the reed is sleeved on the plugging boss through a central hole of the reed and is fixedly connected with the plugging boss, and the outer edge of the reed is fixedly arranged above the valve port;

a plurality of strip-shaped grooves penetrating through the reed along the thickness direction are formed in the reed, each strip-shaped groove comprises a first arc-shaped groove, a second arc-shaped groove and a transition groove, the first arc-shaped grooves and the second arc-shaped grooves circumferentially extend around the central hole, and the radian of each first arc-shaped groove is smaller than that of each second arc-shaped groove; the first arc-shaped groove and the second arc-shaped groove are circumferentially staggered, and the mutually close end parts of the first arc-shaped groove and the second arc-shaped groove are connected through the transition groove; the first arc-shaped groove in each strip-shaped groove is radially arranged at intervals with the second arc-shaped groove in the adjacent strip-shaped groove.

Optionally, the reed is formed with three strip-shaped grooves.

Optionally, a flow guiding blind hole coaxial with the valve core is formed on the plugging boss of the valve core, a plurality of radial flow guiding holes are formed on the side wall of the valve core, the flow guiding blind hole is communicated with the plurality of radial flow guiding holes, and the radial flow guiding holes are communicated with the plurality of air inlets through the cylindrical cavity.

Optionally, two radial guide holes are formed in the valve core, the two radial guide holes are perpendicular to each other, and each radial guide hole penetrates from one side wall of the valve core to the other side wall of the valve core.

Optionally, the flow controller further includes a spring, a side of the valve element facing away from the valve port has a spring positioning surface, one end of the spring faces the spring positioning surface and contacts with the spring positioning surface, and the other end of the spring is fixedly disposed.

Optionally, the spring comprises a cylindrical body, the cylindrical body is provided with a plurality of spiral grooves which penetrate through the side wall of the cylindrical body and extend spirally around the axis of the cylindrical body, the shape and the axial position of the plurality of spiral grooves on the cylindrical body are the same, and the plurality of spiral grooves are arranged at intervals.

Optionally, the cylindrical body is formed with two spiral grooves, the spiral grooves extend around the axis of the cylindrical body in a spiral manner for a circle, and the two spiral grooves are symmetrically arranged around the axis of the cylindrical body.

Optionally, the spring is made of stainless steel, hastelloy or spring steel.

In the flow controller provided by the invention, the air outlet channel in the center of the valve port is connected with the air outlet section of the flow controller fluid channel, and the air inlet holes at the periphery of the air outlet channel are connected with the air inlet section of the flow controller fluid channel, so that the force arm of the reed for bearing fluid pressure is reduced, the moment of force required by pulling the valve core down by the reed is effectively reduced, the stability of the reed under large flow is improved, the service life of the reed is prolonged, the stability of the valve in the flow controller during opening is improved, the phenomenon of internal leakage of the valve in the flow controller is avoided, and the control precision and the repeatability of the flow controller are improved.

Drawings

The accompanying drawings, which are included to provide a further understanding of the invention and are incorporated in and constitute a part of this specification, illustrate embodiments of the invention and together with the description serve to explain the principles of the invention and not to limit the invention. In the drawings:

FIG. 1 is a schematic diagram of a prior art gas flow controller;

FIG. 2 is a simplified schematic diagram of the relative positions of the components of the gas flow controller of FIG. 1;

fig. 3 is a schematic structural diagram of a flow controller according to an embodiment of the present invention;

FIG. 4 is a simplified schematic diagram of the relative positions of components of a flow controller provided by an embodiment of the present invention;

FIG. 5 is an enlarged partial schematic view of the flow controller of FIG. 3;

FIG. 6 is a schematic top view of a valve port in a flow controller provided in accordance with an embodiment of the present invention;

FIG. 7 is a cross-sectional view taken along line A-A of the valve port of FIG. 6;

FIG. 8 is a three-dimensional view of a valve port in a flow controller provided by an embodiment of the present invention;

FIG. 9 is a bottom view of a valve cartridge in a flow controller provided by an embodiment of the present invention;

FIG. 10 is a cross-sectional view taken along line B-B of the valve cartridge of FIG. 9;

FIG. 11 is a schematic flow diagram of a fluid in a flow controller provided by an embodiment of the present invention;

FIG. 12 is a schematic diagram of the construction of a reed in a flow controller according to an embodiment of the present invention;

FIG. 13 is a schematic diagram of a spring in a flow controller according to an embodiment of the present invention;

fig. 14 is a schematic structural diagram of a valve core driving assembly in a flow controller according to an embodiment of the present invention.

Detailed Description

The following detailed description of embodiments of the invention refers to the accompanying drawings. It should be understood that the detailed description and specific examples, while indicating the present invention, are given by way of illustration and explanation only, not limitation.

After the inventor of the present invention has studied the structure of the existing gas flow controller, it is found that the main reason for the inner leakage of the existing gas flow controller is that the reed 3 is easy to fail during the use. Specifically, as shown in fig. 2, which is a simplified schematic diagram of relative positions among the reed 3, the valve element 4 and the valve port 5 in the conventional gas flow controller, the conventional gas flow controller adopts a middle gas inlet manner, that is, a through hole in the center of the valve port 5 is communicated with a gas inlet side, a through hole at the edge of the valve port 5 is communicated with a gas outlet side, gas at the gas inlet side acts upwards on the bottom of the valve element 4 through the through hole in the center of the valve port 5, and the upwards acting force needs to be offset by the elastic force of the reed 3 to avoid internal leakage.

However, when the gas flow controller is a large flow rate gas flow controller (the diameter d of the valve port 5 is large) and the pressure P of the intermediate intake gas is relatively high, the upward thrust F of the gas received at the bottom of the valve element 4 is also relatively large, so that there is a risk of deformation of the reed 3, and a gap is generated between the valve element 4 and the valve port 5, which should be closed, and internal leakage is generated, which affects the accuracy of the gas flow controller.

In order to solve the above technical problem, the present invention provides a flow controller, as shown in fig. 3 and 5, the flow controller includes a base block 140 and a flow control valve, a fluid channel is formed in the base block 140, the fluid channel includes an air inlet section and an air outlet section (ends of the air inlet section and the air outlet section away from the flow control valve are respectively formed as an air inlet and an air outlet of the flow controller), and the flow control valve is disposed on the base block 140 and is configured to selectively communicate the air inlet section and the air outlet section and control a flow cross-sectional area between the air inlet section and the air outlet section, so as to control a flow rate of a fluid.

As shown in fig. 6 to 8, an air outlet channel 112 and a plurality of air inlet holes 111 extending in the same direction are formed in the valve port 110, the axis of the air outlet channel 112 coincides with the axis of the valve port 110, the air outlet channel 112 is communicated with the air outlet section, the air inlet holes 111 are uniformly distributed around the air outlet channel, and the air inlet holes 111 are all communicated with the air inlet section. Reed 100 is used to drive valve plug 90 by spring force to move (i.e., lower) in a direction close to valve port 110 so that valve plug 90 closes off gas outlet channel 112. The valve core driving assembly is used for driving the valve core 90 to move (i.e. rise) along a direction away from the valve port 110 so as to communicate the plurality of air inlet holes 111 and the plurality of air outlet channels 112, and controlling the flow cross-sectional area between the plurality of air inlet holes 111 and the plurality of air outlet channels 112 by controlling the distance of the valve core 90 away from the valve port 110, so as to control the flow cross-sectional area between the air inlet section and the air outlet section.

When the flow controller is in an open state, the valve element driving assembly drives the valve element 90 to overcome the downward acting force of the reed 100, and the valve element rises and leaves the top end of the air outlet channel 112, so that the top end of the air outlet channel 112 is communicated with the top end of the air inlet hole 111, and the air outlet and the air inlet of the flow controller are communicated, and fluid (such as gas) continuously flows along the path of the air inlet section → the air inlet hole 111 → the air outlet channel 112 → the air outlet section; when the flow controller is closed, the valve core driving assembly stops pulling up to drive the valve core 90, the reed 100 drives the valve core 90 to press down and seal the top end of the air outlet channel 112 through elasticity, so that the top end of the air outlet channel 112 is disconnected with the top end of the air inlet hole 111, and a fluid flow path is cut off.

In the flow controller provided by the present invention, the outlet channel 112 in the center of the valve port 110 is connected to the outlet section of the flow controller fluid channel, and the inlet holes 111 around the outlet channel 112 are connected to the inlet section of the flow controller fluid channel, so that the reed 100 overcomes the pressure of the fluid in the peripheral inlet holes 111 by elasticity in the state that the flow controller is closed.

As shown in fig. 4, which is a simplified schematic diagram of relative positions among the valve element 90, the reed 100 and the valve port 110 in the flow controller provided by the present invention, as can be seen from a comparison between fig. 2 and fig. 4, in the conventional central air inlet scheme, a through hole in the center of the valve port (valve port 5 in fig. 2) is communicated with the air inlet side, and the moment arm of the reed (reed 3 in fig. 2) that bears fluid pressure (e.g., air pressure) is a; in the edge air inlet scheme provided by the invention, the valve port 110 is communicated with an air inlet section (air inlet side) of a fluid channel through the peripheral air inlet holes 111, and the force arm B of the reed 100 bearing the fluid pressure is obviously smaller than the force arm A in the central air inlet scheme, so that under the condition of the same reed specification, the moment which is required to bear by the reed 100 to keep the valve core 90 pulled downwards is effectively reduced, the stability of the reed 100 under large flow is improved, the service life of the reed 100 is prolonged, the stability of the valve in the flow controller when the valve is opened is improved, the phenomenon of internal leakage of the valve in the flow controller is avoided, and the control precision and the repeatability of the flow controller are improved.

The flow controller provided by the invention can be used in advanced industries such as semiconductor technology with higher precision requirement, and the like, and the flow controller can adapt to the large flow control requirement, so that the use scene of the flow controller can cover more fields.

The embodiment of the present invention is not particularly limited as to how the outlet channel 112 of the valve port 110 is connected to the inlet hole 111 after the valve element 90 leaves the valve port 110, for example, as an alternative embodiment of the present invention, a flow controller has a chamber for forming a sealed environment, and the valve port 110 is installed in the chamber to separate two ends of the valve port 110 (i.e., two side surfaces corresponding to two ends of the outlet channel 112 and the inlet hole 111) and form a sealed fluid flowing environment on two sides of the valve port 110.

Specifically, as shown in fig. 3 and 5, a cylindrical cavity is formed in the base block 140, the valve port 110 and the valve core 90 are both disposed coaxially with the cylindrical cavity, the valve port 110 is disposed at the bottom of the cylindrical cavity, an outer side wall of the valve port 110 is in sealing fit with an inner wall of the cylindrical cavity, and a portion of the valve core 90 enters the cylindrical cavity from the top of the cylindrical cavity.

In the embodiment of the present invention, the outer sidewall of the valve port 110 is in sealing fit with the inner wall of the cylindrical cavity, so that the fluid at the two ends of the valve port 110 can only communicate through the holes in the valve port 110, i.e. the exhaust port and the intake port of the flow controller can only communicate through the exhaust channel 112 and the intake port 111.

In order to improve the circumferential air inlet uniformity of the valve port 110, as a preferred embodiment of the present invention, as shown in fig. 5 to 8, the air outlet section is communicated with the cylindrical cavity in the central region of the bottom wall of the cylindrical cavity, and further communicated with the air outlet channel 112; the air inlet section is communicated with the cylindrical cavity in the edge area of the bottom wall of the cylindrical cavity, an annular communication groove 113 surrounding the air outlet passage 112 is formed on the surface of one side of the valve port 110, which is far away from the valve core 90, and the air inlet section is communicated with the plurality of air inlet holes 111 through the annular communication groove 113.

In the embodiment of the invention, the plurality of air inlet holes 111 are arranged around the air outlet channel 112 at equal intervals, the bottom ends of the plurality of air inlet holes 111 are communicated with the opening at the bottom of the cylindrical cavity through the annular communicating groove 113 and further communicated with the air inlet of the flow controller, so that the circumferential air inlet uniformity of the valve port 110 is improved, the stability of a fluid flow field above the air inlet holes 111 and the air outlet channel 112 is improved, and the control precision of the flow controller is ensured.

The embodiment of the present invention does not specifically limit how the air inlet and the air outlet communicate with the opening at the bottom of the cylindrical cavity, for example, the air inlet and the air outlet may be connected with the opening at the bottom of the cylindrical cavity through an external pipeline.

Embodiments of the present invention are not particularly limited to the structure for interfacing with the cylindrical groove, and the structure may be part of a spool drive assembly, for example. Specifically, in the flow controller provided in the embodiment of the present invention, the flow control valve may adopt an electromagnetic valve structure, the valve core 90 is an armature of an electromagnetic valve, as shown in fig. 3 and 5, the valve core driving component includes an electromagnetic valve plunger 10, an electromagnetic valve housing 20, a coil 30, an electromagnetic valve flange 70, a valve housing outer ring 80, and the like, the coil 30 is wound outside the electromagnetic valve plunger 10, the electromagnetic valve plunger 10 is used to strengthen a magnetic field generated by the coil 30 to improve an adsorption force (i.e., a lifting force of the pull-up valve core 90) to the valve core 90 below, the electromagnetic valve housing 20 is sleeved outside the electromagnetic valve plunger 10 and the strengthening coil 30, and the bottom of the electromagnetic valve plunger 10 is fixedly connected to the base block 140 through the electromagnetic valve flange 70. The valve sleeve outer ring 80 is fixed on the side wall of the solenoid valve housing 20, the valve sleeve outer ring 80 has a cylindrical inner wall, the inner diameter of the valve sleeve outer ring 80 is matched with the outer diameter of the valve core 90, and the valve core 90 moves up and down in the valve sleeve outer ring 80.

A stepped groove with an inner diameter corresponding to the inner diameter of the cylindrical groove on the base block 140 is formed at the bottom opening of the valve sleeve outer ring 80, when the solenoid valve housing 20 is fixedly connected with the base block 140 through the solenoid valve flange 70, the stepped groove on the valve sleeve outer ring 80 is butted with the cylindrical groove on the base block 140 to form a cylindrical cavity, and the bottom surface of the stepped groove on the valve sleeve outer ring 80 forms the top wall of the cylindrical cavity.

In order to improve the air tightness of the fluid path and prevent the air inlet section and the air outlet section from communicating with each other around the valve port 110, as an alternative embodiment of the present invention, as shown in fig. 5, a sealing stepped groove is formed at the central opening of the bottom of the cylindrical groove, and a valve port sealing ring 130 is disposed in the sealing stepped groove to seal the connection position between the air outlet section and the air outlet channel 112 of the valve port 110.

As an alternative embodiment of the present invention, in order to further improve the air tightness of the fluid path, as shown in fig. 5, a valve port pressing ring 120 is further disposed in the cylindrical cavity, the valve port pressing ring 120 is disposed above the valve port 110, and the sum of the axial dimension of the valve port pressing ring 120 and the axial dimension of the valve port 110 corresponds to the axial dimension of the cylindrical cavity, so that when the solenoid valve housing 20 is fixedly connected to the base block 140, and the stepped groove on the valve housing outer ring 80 is abutted to the cylindrical groove on the base block 140 to form the cylindrical cavity, the valve port pressing ring 120 presses the valve port 110 under the action of the top wall of the cylindrical cavity, and firmly compacts the valve port 110 on the bottom wall of the cylindrical cavity, so that the sealing ring 130 in the sealed stepped groove is compressed, thereby achieving a good sealing effect.

In order to reduce the liquid resistance during the valve core lifting process, as a preferred embodiment of the present invention, as shown in fig. 3 and 5, a valve sleeve cone top 40 is disposed between the valve core 90 and the solenoid plunger 10, a surface of the valve core 90 facing away from the valve port 110 has a tapered portion, a surface of the valve sleeve cone top 40 facing the valve core 90 has a tapered groove, and the taper of the tapered groove on the valve sleeve cone top 40 corresponds to the taper of the tapered portion of the valve core 90.

In the prior art, the top of the valve core is usually designed in a columnar shape, when the top of the valve core enters the corresponding columnar groove, fluid at the bottom of the columnar groove needs to flow out through a gap between the side surface of the valve core and the inner wall of the columnar groove, and as the top of the valve core approaches the bottom of the columnar groove, the path through which the fluid flows out is increased together, the flow rate of the fluid is accelerated, and the work of the valve core required to overcome the fluid resistance is improved. In the embodiment of the invention, the length of the gap between the conical part of the valve core 90 and the conical groove on the valve sleeve conical top 40 is unchanged, and only the thickness is changed, so that extra fluid resistance is not required to be borne in the process of the up-and-down movement of the valve core 90, the smoothness and the stability of the movement of the valve core 90 are improved, and the control precision of the flow controller is further improved.

As an alternative embodiment of the present invention, as shown in fig. 3 and 5, a valve sleeve top ring 60 is further disposed between the valve sleeve outer ring 80 and the valve sleeve conical top 40, when the valve sleeve outer ring 80 is fixed on the side wall of the solenoid valve housing 20, the valve sleeve outer ring 80 pushes the valve sleeve top ring 60 inward, so that the valve sleeve top ring 60 presses the valve sleeve conical top 40 against one side of the solenoid valve plunger 10, and the valve sleeve top ring 60 can be fixed, thereby preventing the valve sleeve top ring 60 from descending along with the valve core 90 when the valve core 90 falls down.

As an alternative embodiment of the present invention, as shown in fig. 9 to 11, a blocking boss 91 is formed in the center of the surface of the valve core 90 on the side facing the valve port 110, for blocking the gas outlet passage 112; the reed 100 is ring-shaped, the reed 100 is sleeved on the plugging boss 91 through the central hole thereof and is fixedly connected with the plugging boss 91, and the outer edge of the reed 100 is fixedly arranged above the valve port 110.

For the flow controller, the model selection and manufacture of the reed usually pursues the small valve port high lift, rather than the large valve port small lift, that is, the valve port lift is preferentially lengthened (i.e. the strain of the reed is increased) to adapt to the requirement of large flow, so that the flow controller is easier in flow control, and the flow control precision can be effectively improved. Under the standard, the reed needs to have enough deformation amount to meet the requirement of the lift, so the reed can not be too thin (the reed can concentrate stress or has too large instantaneous deformation to cause unstable flow) or too thick (the reed can not have enough magnetic force of a valve core and has insufficient lift), namely, the stress on the reed needs to be reduced as much as possible, and meanwhile, the flexibility of the reed needs to be improved.

In order to meet the above requirement, as a preferred embodiment of the present invention, as shown in fig. 10, a plurality of strip-shaped grooves penetrating through the reed 100 along the thickness direction are formed on the reed 100, each strip-shaped groove includes a first arc-shaped groove 101, a second arc-shaped groove 102 and a transition groove 103, the first arc-shaped groove 101 and the second arc-shaped groove 102 both extend circumferentially around the central hole, and the radian of the first arc-shaped groove 101 is smaller than that of the second arc-shaped groove 102; the first arc-shaped groove 101 and the second arc-shaped groove 102 are circumferentially staggered, and the mutually close ends of the first arc-shaped groove 101 and the second arc-shaped groove 102 are connected through a transition groove 103; the first arc-shaped groove 101 in each strip-shaped groove is radially arranged at intervals with the second arc-shaped groove 102 in the adjacent strip-shaped groove.

Embodiments of the invention are not particularly limited as to the number of strip-shaped grooves on the spring sheet 100, for example, alternatively, as shown in FIG. 10, three strip-shaped grooves can be formed on the spring sheet 100. In the embodiment of the invention, the reed 100 is divided into the coaxial inner ring and the coaxial outer ring by the plurality of strip-shaped grooves, the spacing area between the first arc-shaped groove 101 in each strip-shaped groove and the second arc-shaped groove 102 in the adjacent strip-shaped groove forms a connecting arm for connecting the inner ring and the outer ring, when the valve core 90 is pulled up and drives the inner ring to ascend, the plurality of connecting arms deform and generate elastic stress, and the stress which needs to be distributed in the radial direction originally and the corresponding strain are uniformly distributed on the plurality of connecting arms which extend in the spiral direction, so that the stress distributed on the reed is reduced while the low thickness of the reed 100 is kept, and the flexibility of the reed is improved.

The inventor also finds that the accuracy of the large-flow controller is insufficient and internal leakage is easy to occur due to the fact that the flow cross-sectional area of the novel valve port is large under the condition of certain pressure, but the bottom of the valve core is still of a solid structure, and the impact of the whole air flow on the bottom of the valve core is large at the moment when the armature valve core is lifted, so that the reed is easy to deform and damage, and the accuracy of the flow controller is affected.

In order to solve the above technical problems, as a preferred embodiment of the present invention, as shown in fig. 9 to 11, a blind flow guiding hole 92 coaxial with the valve core 90 is formed on the blocking boss 91 of the valve core 90, a plurality of radial flow guiding holes 93 are formed on the side wall of the valve core 90, the blind flow guiding hole 92 is communicated with the plurality of radial flow guiding holes 93, and the radial flow guiding holes 93 are communicated with a plurality of air inlet holes 111 through a cylindrical cavity (in a case that the valve sleeve top ring 60 is disposed above the valve port 110, a gap exists between the valve sleeve top ring 60 and the valve core 90, so that a top space of the valve port 110 is communicated with the radial flow guiding holes 93).

As shown in fig. 11, which is a schematic view of a fluid flow direction in a cylindrical cavity, in the embodiment of the present invention, the radial flow guide holes 93 are communicated with the plurality of radial flow guide holes 93 through the cylindrical cavity, so that in a fluid flow process, fluid can flow to a fluid passage formed by the radial flow guide holes 93 and the flow guide blind holes 92 to flow to the air outlet channel 112 through the cylindrical cavity, in addition to a path from the air inlet hole 111 to the air outlet channel 112 through the cylindrical cavity, an exhaust area is increased, and impact on the bottom of the valve core is reduced through a flow dividing effect, so that deformation and damage of the reed can be effectively avoided, and flow control accuracy of the flow controller is improved.

In order to further improve the stability of the fluid flow field above the valve port 110, as a preferred embodiment of the present invention, the air outlet channel 112 is designed in a stepped manner, as shown in fig. 6, 7 and 11, the air outlet channel 112 includes an air outlet hole formed on a surface of one side of the valve port 110 facing away from the valve core 90 and coaxial with the valve core 90, a plurality of exhaust holes penetrating through a surface of one side of the valve port 110 facing toward the valve core 90 are formed at the bottom of the air outlet hole, the exhaust holes are distributed at equal intervals around an axis of the valve port 110, a pitch circle diameter of the exhaust holes is larger than a diameter of the flow guiding blind hole 92, the valve core 90 is used for selectively closing the exhaust holes, and the air outlet hole is communicated with the air inlet and outlet channels.

In the embodiment of the present invention, the air outlet channel 112 is communicated with the upper space through a plurality of air outlet holes distributed circumferentially, so that in the process of fluid flowing, as shown in fig. 11, the blind guiding hole 92 flows the fluid flowing downward vertically and the fluid flowing from the air inlet hole 111 to the air outlet holes, and can simultaneously exhaust the air to the air outlet holes along the inner ring and the outer ring of the reference circle where the air outlet holes are located, and the fluids in the two fluid paths do not disturb each other before, thereby improving the stability of the fluid flow field above the valve port 110 and the flow control accuracy of the flow controller.

In order to improve the stability of the fluid flow field in the flow controller and simplify the manufacturing process of the radial guide holes 93, as a preferred embodiment of the present invention, two radial guide holes 93 are formed in the valve core 90, the two radial guide holes 93 are perpendicular to each other, and each radial guide hole 93 penetrates from one side wall of the valve core 90 to the other side wall.

The inventor also finds that the basic principle of the normally closed electromagnetic valve is that the valve core and the valve port are tightly pressed when electricity is not supplied, the air path is blocked, and no air passes through. After power is supplied, the opposite magnetic poles attract each other to enable the armature valve core to move, and the movement of the valve core enables the spring to deform. The magnetic force is balanced with the spring force generated by the spring deformation. The spool will stay at the equilibrium point, at which time the flow capacity is the gas flow.

As shown in fig. 2, when the valve element moves h, the flow cross-sectional area a is pi d h. The existing solenoid valve adopts a single reed structure, as shown in fig. 2. There are two risks associated with using only one reed. One risk is that the spring 3 is not large enough in elasticity and is easily deformed when the air inlet pressure is too large, so that the air path is not sealed and internal leakage is caused. Another risk is that the stability of the action of the single reed 3 stabilizing valve is insufficient, the valve control is unstable, and the overshoot phenomenon at the beginning of the movement of the control spool is significant.

To solve the above technical problem, as a preferred embodiment of the present invention, as shown in fig. 3, 5, 13 and 14, the flow controller further includes a spring 50, a side of the valve core 90 facing away from the valve port 110 has a spring positioning surface 94, one end of the spring 50 faces the spring positioning surface 94 and contacts with the spring positioning surface 94, and the other end of the spring 50 is fixedly connected (with a fixed member (a member fixed in position relative to the base block 140) in the mass flow controller, for example, when the valve sleeve top ring 60 is present, the other end of the spring 50 is fixedly arranged on the valve sleeve top ring 60, and the spring 50 is sleeved on the tapered portion).

In the present embodiment, spring 50 cooperates with reed 90, and the two cooperate to balance the electromagnetic lift force experienced by valve element 90. That is, in the using process of the flow controller, the control device provides a certain voltage to the valve core driving assembly, so that the valve core 90 (armature) starts to move upwards, at this time, the reed 90 deforms to generate an elastic force, the mechanical spring is also compressed and deformed to generate an elastic force, the resultant force of the two elastic forces is equal to the electromagnetic force received by the armature, so that the acting force required to be borne by the reed 90 is shared by the spring 50, the stress on the reed 90 is effectively reduced, the stability of the valve structure when the valve structure is opened is improved, the flow control precision of the flow controller is improved, and the service life of the flow controller is prolonged.

To improve the strength of the spring 50, as a preferred embodiment of the present invention, the spring 50 is customized by machining, i.e., forming a helical groove in the cylindrical metal member to form the spring structure. Specifically, as shown in fig. 13, the spring 50 includes a cylindrical body formed with a plurality of helical grooves extending through a side wall of the cylindrical body and helically extending around an axis of the cylindrical body, the plurality of helical grooves being identical in shape and axial position on the cylindrical body, the plurality of helical grooves being spaced apart from each other.

The number of the spiral grooves formed on the cylindrical body is not particularly limited in the embodiment of the present invention, and can be determined by a person skilled in the art according to the magnitude of the electromagnetic lift force required to be borne by the person and the stroke length of the valve element 90. For example, as an easily realized embodiment, as shown in fig. 13, two spiral grooves are formed on the cylindrical body, the spiral grooves spirally extend for one circle around the axis of the cylindrical body, and the two spiral grooves are symmetrically arranged about the axis of the cylindrical body.

In order to increase the flexibility of the spring 50, the spring 50 is made of a material with high elasticity as a preferred embodiment of the present invention, for example, the material of the spring 50 may be stainless steel, hastelloy or spring steel.

In the flow controller provided by the invention, the gas outlet channel 112 in the center of the valve port 110 is connected with the gas outlet of the flow controller, and the gas inlet holes 111 at the periphery of the gas outlet channel 112 are connected with the gas inlet of the flow controller, so that the force arm of the reed 100 bearing the fluid pressure is reduced, the moment of the reed 100 required for keeping the valve core 90 pulled down is effectively reduced, the stability of the reed 100 under large flow is further improved, the service life of the reed 100 is prolonged, the stability of a valve in the flow controller during opening is improved, the phenomenon of valve internal leakage in the flow controller is avoided, and the control precision and the repeatability of the flow controller are further improved.

It will be understood that the above embodiments are merely exemplary embodiments taken to illustrate the principles of the present invention, which is not limited thereto. It will be apparent to those skilled in the art that various modifications and improvements can be made without departing from the spirit and substance of the invention, and these modifications and improvements are also considered to be within the scope of the invention.