阅读说明：本技术 破碎机的缓冲油缸 (Buffer oil cylinder of crusher ) 是由 王永芳 王海洋 任启鹏 王守仁 于 2019-11-15 设计创作，主要内容包括：本发明公开了一种破碎机的缓冲油缸,包括缸体、安装在缸体内的活塞和安装在缸体两端的各一个带有油口的缸盖,两缸盖中的第二缸盖带有中心孔,适配于活塞的推杆自所述中心孔探出,于两缸盖或配装于给定缸盖的阀块上各设有一柱塞阀,柱塞阀用于所述油口的启闭；柱塞阀的阀杆垂直于活塞的端面,并为所述活塞所作动；油口所适配流道安装柱塞阀的部分与所述阀杆垂直；其中,柱塞阀为其柱塞配有反向于活塞对该柱塞作动方向的复位装置。依据本发明的破碎机的缓冲油缸能够有效降低液压冲击和机械冲击。(The invention discloses a buffer oil cylinder of a crusher, which comprises a cylinder body, a piston arranged in the cylinder body and cylinder covers with oil ports, wherein the cylinder covers are respectively arranged at two ends of the cylinder body; the valve rod of the plunger valve is vertical to the end surface of the piston and is actuated by the piston; the part of the flow passage matched with the oil port, on which the plunger valve is arranged, is vertical to the valve rod; the plunger valve is characterized in that a plunger of the plunger valve is provided with a resetting device which is opposite to the action direction of the piston to the plunger. The buffer oil cylinder of the crusher can effectively reduce hydraulic impact and mechanical impact.)

1. A buffer oil cylinder of a crusher comprises a cylinder body, a piston arranged in the cylinder body and cylinder covers with oil ports respectively arranged at two ends of the cylinder body, wherein a second cylinder cover in the two cylinder covers is provided with a central hole, and a push rod adaptive to the piston extends out of the central hole;

the valve rod of the plunger valve is vertical to the end surface of the piston and is actuated by the piston;

the part of the flow passage matched with the oil port, on which the plunger valve is arranged, is vertical to the valve rod;

the plunger valve is characterized in that a plunger of the plunger valve is provided with a resetting device which is opposite to the action direction of the piston to the plunger.

2. The cushion cylinder of the crusher according to claim 1, wherein a first cylinder cover of the two cylinder covers is used as a mounting base of a first plunger valve of the two plunger valves;

the first cylinder cover is provided with two blind holes vertical to the end face of the first cylinder cover, one blind hole is a first valve cavity of the first plunger valve, and the other blind hole is a first part of a first oil duct of a first oil port opened by the first cylinder cover;

the first oil duct comprises a second part communicated with the two blind holes, and the second part is perpendicular to the two blind holes; the part of the first oil port communicated with the second part is a third part.

3. The cushion cylinder of the crusher of claim 2, wherein the bore diameter of the third portion is larger than the bore diameter of the second portion;

the third portion extends to the side of the valve chamber where the first portion is located.

4. The cushion cylinder of the crusher according to claim 1, wherein a valve block is provided on a second cylinder head side of the two cylinder heads, the valve block is provided with an axial through hole for a push rod to pass through, and a first channel is formed between a wall of the through hole and the push rod, wherein the aperture of the through hole is larger than the diameter of the push rod;

the valve block is provided with a second valve cavity at one side of the first channel and used as a valve cavity of a second plunger valve in the two plunger valves;

a communication passage for communicating the second valve chamber with the first passage is provided, the communication passage being perpendicular to the valve stem.

5. The cushion cylinder of the crusher according to claim 4, wherein the valve block is in interference fit with the cylinder body; and the valve block is made of elastic material with the compression rate of 1% -4%.

6. The cushion cylinder of the crusher according to claim 4, wherein a cushion spring is provided on a side of the piston facing the valve block, or on a side of the valve block facing the piston;

the buffer spring is a conical spring, the axial projection of the conical spring on the piston is a vortex line, and adjacent turns of the vortex line are just contacted or separated.

7. The cushion cylinder of a crusher as claimed in claim 1, wherein the return means is a return spring.

8. A breaker cylinder according to claim 7 wherein the return spring is supported at one of the two ends of the same plunger and the other end is adapted to receive a hold spring.

9. The cushion cylinder of the crusher according to claim 1, wherein the cylinder body is flange-connected to the cylinder head.

10. The cushion cylinder of a crusher as claimed in claim 1, wherein the diameter of the portion of the oil passage fitted with the plunger valve fitted to the oil port is smaller than the operating stroke of the plunger.

Technical Field

The invention relates to an oil cylinder with a buffer device, which is specially used for crushing wastes.

Background

The working environment of the oil cylinder equipped in the crusher is severe, such as the oil cylinder disclosed in chinese patent document CN105298976A and the oil cylinder disclosed in chinese patent document CN 107975514A. Because the working pressure of the hydraulic oil adapted to the oil cylinder is usually higher, according to the provisions of mechanical design manual, the working pressure of the hydraulic oil is divided into five types, namely low pressure, medium-high pressure, high pressure and ultrahigh pressure, even if the pressure is low, the magnitude is also MPa, namely the application is lower than 10MPa, and the working pressure of the oil cylinder used by the crusher is usually in the medium-pressure or medium-high pressure range.

Hydraulic shock and mechanical shock are two inherent problems in the use of hydraulic cylinders, and the hydraulic shock is defined by mechanical design manual, wherein when a valve in a pipeline is suddenly closed, the fluid in the pipeline is suddenly stopped to cause pressure rise, and the pressure rise can cause great damage to a hydraulic system. The magnitude of the hydraulic shock is positively correlated with the speed at which the valve closes and with the working pressure of the hydraulic system. The mechanical impact is equivalent to other types of mechanical impact, namely the mechanical impact between the piston of the oil cylinder and the cylinder cover after the piston of the oil cylinder is in place is great in damage to the cylinder body, and other hydraulic elements are not affected; mechanical impact also produces noise.

Chinese patent document CN108757632A discloses a cylinder which has a high response speed and is liable to generate larger noise than a hydraulic cylinder, but the impact of a pneumatic system is relatively weak due to a small working pressure. In order to overcome the noise generated by the mechanical impact of the cylinder itself, in the patent document, a hollow piston is adopted, and a hollow structure is provided on the end cover on the side of the rodless cavity, and the hollow piston has a buffering effect based on the compression generated by the impact of the hollow piston and the rodless cavity, thereby reducing the noise. However, the structure can affect the stop control more, and for the hydraulic cylinder with larger working pressure, the control of the compression amount of the buffer structure is more difficult, so that the working stroke of the piston cannot be accurately controlled.

Chinese patent document CN208281275U discloses an oil cylinder which also adopts a buffering manner, that is, a buffer member is disposed at the bottom of the cylinder body. Because of the existence of the buffer member, the problem of the control precision of the working stroke is inevitable.

In contrast, chinese patent document CN109340216A discloses a valve control-based cushion cylinder, in which a piston divides an oil chamber into a first oil chamber and a second oil chamber, and a pair of check valves is disposed on the piston, one of the check valves is actuated and conducted based on the pressing force between the check valve and a left end cap, and the other check valve is actuated and conducted based on the pressing force between the check valve and a right end cap, so that at two branch points of the piston movement, because a conducting portion exists on the piston, the oil drainage amount is increased, which is equivalent to that, the movement speed of the piston is slowed down, thereby reducing the force of impact. The construction of the non-return valve on the piston considerably increases the thickness of the piston, with relatively great difficulty both with regard to the assembly of the piston and with regard to the design of the working stroke.

Disclosure of Invention

In view of the above, the present invention is directed to a cushion cylinder of a crusher capable of effectively reducing hydraulic impact and mechanical impact.

In an embodiment of the invention, a buffer oil cylinder of a crusher is provided, which comprises a cylinder body, a piston arranged in the cylinder body and cylinder covers with oil ports respectively arranged at two ends of the cylinder body, wherein a second cylinder cover in the two cylinder covers is provided with a central hole, a push rod adapted to the piston extends out of the central hole, and the two cylinder covers or a valve block assembled on a given cylinder cover are respectively provided with a plunger valve for opening and closing the oil ports;

the valve rod of the plunger valve is vertical to the end surface of the piston and is actuated by the piston;

the part of the flow passage matched with the oil port, on which the plunger valve is arranged, is vertical to the valve rod;

the plunger valve is characterized in that a plunger of the plunger valve is provided with a resetting device which is opposite to the action direction of the piston to the plunger.

Optionally, a first cylinder cover of the two cylinder covers is used as a mounting base body of a first plunger valve of the two plunger valves;

the first cylinder cover is provided with two blind holes vertical to the end face of the first cylinder cover, one blind hole is a first valve cavity of the first plunger valve, and the other blind hole is a first part of a first oil duct of a first oil port opened by the first cylinder cover;

the first oil duct comprises a second part communicated with the two blind holes, and the second part is perpendicular to the two blind holes; the part of the first oil port communicated with the second part is a third part.

Optionally, the aperture of the third portion is larger than the aperture of the second portion;

the third portion extends to the side of the valve chamber where the first portion is located.

Optionally, a valve block is arranged on the side of a second cylinder cover of the two cylinder covers, the valve block is provided with an axial through hole for the push rod to pass through, and the aperture of the through hole is larger than the diameter of the push rod to form a first channel between the wall of the through hole and the push rod;

the valve block is provided with a second valve cavity at one side of the first channel and used as a valve cavity of a second plunger valve in the two plunger valves;

a communication passage for communicating the second valve chamber with the first passage is provided, the communication passage being perpendicular to the valve stem.

Optionally, the valve block is in interference fit with the cylinder body; and the valve block is made of elastic material with the compression rate of 1% -4%.

Optionally, a buffer spring is arranged on one surface of the piston facing the valve block, or one surface of the valve block facing the piston;

the buffer spring is a conical spring, the axial projection of the conical spring on the piston is a vortex line, and adjacent turns of the vortex line are just contacted or separated.

Optionally, the return means is a return spring.

Optionally, one of the two ends of the same plunger supports the return spring, and the other end is adapted with a holding spring.

Optionally, the cylinder body and the cylinder cover are in flange connection.

Optionally, the bore diameter of the part of the oil passage fitting the plunger valve and adapted to the oil port is smaller than the working stroke of the plunger.

In embodiments of the invention, it will be appreciated that the plunger valve must be open before the piston is not in contact with the valve stem of the plunger, otherwise the piston cannot move. In addition, in the mechanical field, it can be understood that the opening and closing of the plunger is a process of gradually changing the opening degree, in other words, when the valve rod is acted by the piston, the plunger valve is gradually closed, and accordingly, the speed of the piston is gradually slowed to stop, and the process is a gradual process, which is realized not based on the buffering of the buffering component on the piston, but based on the gradual stopping of the hydraulic circuit, and the precision of the working stroke of the buffering oil cylinder is not influenced thereby. For mechanical impact and hydraulic impact, as the closing of the oil outlet is gradual, the mechanical impact and the hydraulic impact can be effectively relieved, and a hydraulic system can be effectively protected.

Drawings

Fig. 1 is a schematic cross-sectional structure diagram of a cushion cylinder in an embodiment.

In the figure: 1. the hydraulic cylinder comprises a first cylinder cover, 2, a first oil port, 3, a first oil channel, 4, a first spring, 5, a first plunger, 6, a second spring, 7, a second oil channel, 8, a first positioning rod, 8, an oil cavity, 10, a sealing ring, 11, a sealing ring, 12, a piston, 13, a conical spring, 14, a second positioning rod, 15, a third spring, 16, a second plunger, 17, a second oil port, 18, a push rod, 19, a second cylinder cover, 20, a sealing ring, 21, 22, a fourth spring, 23, a communication oil channel, 24, a shaft hole, 25, a valve block and 26, and a valve body.

Detailed Description

Referring to the attached fig. 1 of the specification, there are two oil ports, i.e., the first oil port 2 and the second oil port 17, and the oil cylinder is a double-acting cylinder, i.e., the first oil port 2 and the second oil port 17 are used as an oil inlet and an oil outlet, and in the technical field of hydraulic cylinders, the two oil ports are generally defined as an a port and a B port.

With regard to the figures, in which the first plunger valve is comprised by the first plunger 5 and the second plunger valve is comprised by the second plunger 16, it is understood that both plunger valves are necessarily open without the piston 12 coming into contact with the respective valve stem, otherwise the oil chamber 9 is closed and the piston 12 cannot move.

Regarding the valve stem, in fig. 1 positioning rods are used for illustration, such as the first positioning rod 8 and the second positioning rod 14 shown in the figure, and the positioning rods are used for illustration of the valve stem, which in some applications is used for determining the working stroke of the plunger, and thus are functionally positioned.

In addition, regarding the hydraulic cylinder, which is distinguished from the air cylinder, the hydraulic cylinder operates relatively smoothly, and at the same time, the operating speed thereof is relatively small. In particular, unlike a cylinder, which is a gas with a relatively large compression ratio as the working medium, a hydraulic cylinder, whose working medium is a liquid with a nearly negligible compression ratio, the speed of a hydraulic system, for example, a hydraulic cylinder, is directly related to the flow rate of the associated hydraulic circuit. The plunger valve belongs to a valve which is gradually closed or opened, and the opening degree of the corresponding plunger valve is directly related to the pressing-in amount of the first positioning rod 8, the more the pressing-in amount is, the smaller the opening degree is, and the smaller the opening degree is, the smaller the flow rate of hydraulic oil is, the slower the speed of the piston 12 is, so that the piston is gradually stopped, and the hydraulic impact and the mechanical impact are effectively reduced.

In particular, the buffer cylinder of a crusher shown in fig. 1 is horizontally disposed, and as for the cylinder body 26 (also called cylinder barrel), it is a cylinder structure as a whole, and therefore has a definite axial direction, radial direction and circumferential direction, the piston 12 is matched with the cylinder body 26 to form a moving pair, and the main body of the piston 12 in the conventional structure is a short cylinder structure.

The two ends of the cylinder body 26 are sealed through cylinder covers, the cylinder body is adapted to the cylindrical structure of the cylinder body 26, the sealing is completed by two cylinder cover adaptation fasteners (mostly bolts) and sealing pieces (mostly rubber sealing rings), and specifically, a first cylinder cover 1 located at the left end of the cylinder body 26 and a second cylinder cover 19 located at the right end of the cylinder body 26 can be seen.

The connection between the cylinder cover and the cylinder body 26 usually adopts flange connection, the flange is provided with at least three bolt holes, but usually not more than six, and the bolt connection is convenient for dismounting.

The connection between the cylinder head and the cylinder body 26 is not specifically shown in fig. 1, and the assembly structure between the two is a conventional structure in the art and is not described herein again.

With respect to the conventional construction of the hydraulic cylinder, it is also possible to see the piston 12 and the push rod 18 and their assembly, wherein the push rod 18 will be referred to as a piston rod in more applications, which may be fixedly connected to the piston 12 or formed as a one-piece structure.

In general, it is relatively difficult to open the oil port for the cylinder body 26 of the double acting cylinder, and therefore, in more applications, the oil port is opened on the cylinder head, as in fig. 1, the first oil port 2 is opened on the first cylinder head 1, and the second oil port 17 is opened on the second cylinder head 19.

Wherein the second cylinder head 19 is provided with a central bore from which a push rod 18 adapted to the piston 12 protrudes. Accordingly, the sliding fit between the push rod 18 and the second cylinder cover 19 requires a sealing structure for the sliding surface, such as a sealing ring 20 and two sealing rings 21 shown in fig. 1, wherein the sealing ring 20 is an oil seal, and the sealing ring 21 is a dust seal.

With respect to the two plunger valves, one may be provided on each of the two cylinder heads, or may be provided on an additional structure, such as the valve block 25 shown in fig. 1.

The piston 12 divides the oil chamber 9 into left and right two parts as shown in fig. 1, wherein the first oil port 2 is communicated with the left oil chamber located on the left side through a first oil port oil passage, and the second oil port 17 is communicated with the right oil chamber located on the right side through a second oil port oil passage. One of the two plunger valves is used for controlling opening and closing of the first oil port and the other plunger valve is used for controlling opening and closing of the second oil port and the oil duct.

In the configuration shown in fig. 1, the valve stems of the two plunger valves, i.e. the first positioning rod 8 and the second positioning rod 14 shown in the figure, project into the respective oil chambers in the direction of the respective valve covers, the length of which projecting out of the respective valve covers determines the working stroke of the respective plunger valves, and can be easily designed by those skilled in the art.

Correspondingly, at two end sections of the working stroke of the piston 12, the piston 12 is in contact with the corresponding valve rod, and then the valve rod is pushed to move forwards, so that the corresponding plunger is driven to move forwards, the corresponding oil port and oil passage are gradually closed until the corresponding oil port and oil passage are completely closed, and in the process, the oil port and oil passage are gradually closed.

After the piston 12 is out of contact with the corresponding valve stem, the corresponding port oil passage should be opened, and therefore, the corresponding plunger valve should be automatically reset, and the means for automatically resetting is denoted as a resetting means, and in the structure shown in fig. 1, for example, the first spring 4, the fourth spring 22 are provided for reversing the direction of actuation of the corresponding valve stem by the piston 12, and thus for resetting the applied plunger.

In some embodiments, the cylinder head on the left as shown in fig. 1, i.e. the first cylinder head 1 as shown in the drawing, directly serves as a mounting base for the first plunger valve of the two plunger valves, and the first port oil gallery is directly formed on the first cylinder head 1.

Seen from the right side in fig. 1, the first cylinder head 1 is provided with two blind holes perpendicular to the right end surface of the first cylinder head 1, one blind hole is configured as a first valve cavity of the first plunger valve, and the other blind hole is configured as a first part of a first oil duct of a first oil port opened by the first cylinder head 1, i.e. a horizontal part in fig. 1.

Wherein the blind hole configured as the first valve chamber is deeper than the blind hole configured as the first part. Furthermore, the first oil duct, i.e. the first oil port oil duct, includes a second portion communicating the two blind holes, i.e. the vertical oil duct portion of the first cylinder head in fig. 1, which is located below the first plunger 5, and the second portion is perpendicular to the two blind holes; the part of the first oil port communicated with the second part is a third part. In this structure, the lower side surface of the first plunger 5 gradually closes the second portion in the leftward movement process of the first plunger 5, so as to gradually close the first port oil passage.

Accordingly, when the piston 12 moves to the right, the first plunger 5 gradually returns to the right under the elastic force of the first spring 4, and the shielding of the second portion becomes smaller and smaller.

In the configuration shown in fig. 1, the third portion has a larger bore than the second portion and the second portion is biased to the right, so that there is a shoulder between the second and third portions, facilitating the placement of the first spring 4 and facilitating the setting of the first plunger 5.

Accordingly, the third portion extends to the side of the valve chamber where the first portion is located.

Different from the first cylinder cover 1, the second cylinder cover 19 side of the two cylinder covers is provided with a valve block 25, the valve block 25 is provided with an axial through hole 24 for the push rod 18 to pass through, and the aperture of the through hole 24 is larger than the diameter of the push rod 18, so that a first channel is formed between the wall of the through hole and the push rod 18.

The valve block 25 has a second valve chamber on one side of the first passage, which serves as a valve chamber of the second of the two plunger valves.

A communication passage for communicating the second valve chamber with the first passage is provided, the communication passage being perpendicular to the valve stem.

In contrast, the speed of the working stroke of the piston 12 is faster than the return stroke speed, in other words, the impact generated by the working stroke is stronger, and for this reason, the valve block 25 and the cylinder 26 are in interference fit; and the valve block 25 is made of an elastic material with the compression rate of 1% -4%. After the piston 12 is right-hand advanced into position, it can be better cushioned by the valve block 25.

In addition, the compression ratio of the common rubber can meet the requirement of the compression ratio, and under the condition, the compression amount of the valve block 25 is limited, so that the structure of the second plunger valve is not influenced; especially with the aforementioned interference fit, the valve block 25 has already been pre-stressed by a fraction.

In the structure shown in fig. 1, a buffer spring, such as the conical spring 13 shown in fig. 1, is provided on a surface of the piston 12 facing the valve block 25, or a surface of the valve block 25 facing the piston 12.

Further, the axial projection of the conical spring 13 on the piston is a vortex line, adjacent turns of the vortex line are just contacted or separated, so that the conical spring 13 is approximately in a sheet structure after being pressed, the thickness of the sheet structure is determined, and therefore, the working stroke of the hydraulic cylinder is not affected under the condition that the conical spring 13 is arranged.

In some embodiments, the return spring is supported at one of the two ends of the same plunger, the other end being adapted with a holding spring. Referring specifically to the first spring 4 and the second spring 6 in the figures, the second spring 6 may hold the first plunger 5 in a relatively appropriate position.

In a preferred embodiment, the bore diameter of the portion of the oil passage fitting the plunger valve fitted to the oil port is smaller than the working stroke of the plunger.