Driving assembly adopting two-way piston to control transmission torque and friction clutch

Abstract

The invention discloses a driving assembly adopting a bidirectional piston to control transmission torque and a friction clutch, and relates to the technical field of clutches. The problems that an existing friction clutch fluid medium pressure control element is complex in structure, high in manufacturing cost and relatively low in reliability are solved. According to the device, the oil cylinder body, the oil tank, the driving piston and the pressure oil pipeline are included, the oil cylinder body is fixedly installed on the driving shaft, the first reversing valve is opened, pressure oil is injected into the pressing cavity, axial force in one direction is generated on the pressing piston, the first reversing valve and the second reversing valve are opened, and the pressure oil is injected into the pressing cavity and the loosening cavity at the same time; the compression piston is subjected to two axial forces in opposite directions, the two axial forces counteract each other to reduce the compression force of the compression piston, the combined compression force of the compression piston to the friction plate group can be realized through opening and closing of the first reversing valve and the second reversing valve, adopted control elements are all switch direction valves, the structure is simple, the cost is low, and the reliability is high. The manufacturing cost is lower, and the reliability is better.

Description

Technical Field

[0001] The present invention relates to the technical field of clutches, and particularly to a drive assembly and a friction clutch that use a two-way piston to control torque transmission. Background Art

[0002] Currently, the generally known friction clutch generally uses a single-direction output piston to press the friction plate group to transmit frictional torque. During the engagement process of the friction clutch, the method of controlling the pressure of the working medium entering the piston chamber of the friction clutch is used to control the torque transmitted by the friction clutch.

[0003] The components for controlling the pressure of the working medium are generally overflow valves, pressure reducing valves, secondary pressure regulating valves, proportional servo valves, etc. Generally speaking, the pressure control components of fluid media have complex structures (such as internal damping holes and throttle openings required for pressure feedback), high manufacturing costs, high requirements for the filtration accuracy of the working medium, and relatively low reliability.

[0004] In summary, the existing pressure control components of fluid media in friction clutches have complex structures, and there are problems of high manufacturing costs and relatively low reliability. Summary of the Invention

[0005] The purpose of the present invention is to solve the problems that the existing pressure control components of fluid media in friction clutches have complex structures, high manufacturing costs, and relatively low reliability. Furthermore, a drive assembly and a friction clutch that use a two-way piston to control torque transmission are provided.

[0006] The technical solution of the present invention is: a drive assembly that uses a two-way piston to control torque transmission, including: an oil cylinder body, an oil tank, a drive piston, and a pressure oil pipeline. The oil cylinder body is fixedly installed on the driving shaft, the oil cylinder body is connected to the oil tank, and the oil inlet of the main oil path on the pressure oil pipeline is communicated with the oil tank;

[0007] The drive piston is slidably installed on the driving shaft and the oil cylinder body. A pressing cavity is formed between the drive piston, the oil cylinder body, and the driving shaft, and a relaxation cavity is formed between the drive piston and the oil cylinder body. A relaxation oil path and a pressing oil path are provided on the driving shaft. The relaxation oil path is communicated with the relaxation cavity, and the pressing oil path is communicated with the pressing cavity;

[0008] The pressure oil pipeline includes a main oil path, a first branch oil path, and a second branch oil path. The first branch oil path is communicated with the pressing oil path, and the second branch oil path is communicated with the relaxation oil path;

[0009] A first reversing valve is provided on the first branch oil path, a second reversing valve is provided on the second branch oil path, and the outlets of the first reversing valve and the second reversing valve are both communicated with the oil tank.

[0010] Further, the first reversing valve is a power-off holding electromagnetic reversing valve, and the second reversing valve is a hydraulically controlled reversing valve.

[0011] Further, the pressure oil pipeline further includes: a third oil branch. One end of the third oil branch communicates with a position on the first oil branch downstream of the first reversing valve, and the other end of the third oil branch communicates with the control port of the second reversing valve;

[0012] In the third oil branch, the pressure oil flows from the first oil branch to the second oil branch. A third reversing valve and a fourth reversing valve are arranged on the third oil branch along the flowing direction of the pressure oil.

[0013] Further, the third reversing valve is a differential pressure check valve, and the fourth reversing valve is an automatic reset electromagnetic reversing valve.

[0014] Further, the driving piston includes a release piston and a pressing piston fixedly connected. The release piston is slidably installed on the cylinder block, and the pressing piston is slidably installed on the cylinder block and the driving shaft.

[0015] Further, an oil discharge port for communicating the release chamber with the outside is provided on the release piston, and an oil drain plug is fixedly installed at the oil discharge port.

[0016] Further, a friction clutch includes: a driving shaft, a friction plate group, an external gear ring, an elastic member, and a driving assembly for controlling torque transmission by using a two-way piston in any one of the above solutions. A plurality of driving plates of the friction plate group are key-connected to the driving shaft, a plurality of driven plates of the friction plate group are key-connected to the external gear ring, and a baffle protruding radially outward is fixedly connected to one end of the driving shaft. The baffle abuts against one side of the friction plate group;

[0017] The elastic member is connected to the driving piston of the driving assembly for controlling torque transmission by using a two-way piston, and the elastic member has an elastic force for pushing the driving piston away from the friction plate group;

[0018] When the pressing chamber of the driving assembly for controlling torque transmission by using a two-way piston is filled with pressure oil, the driving piston overcomes the elastic force of the elastic member and presses against the other side of the friction plate group.

[0019] Further, the driving shaft has a friction seat, and a plurality of driving plates of the friction plate group are key-connected to the friction seat.

[0020] Further, the friction seat has an installation groove with an opening facing the driving piston. One end of the elastic member abuts against the side wall of the installation groove, and the other end of the elastic member abuts against the driving piston.

[0021] Further, the elastic member is a spring.

[0022] The present invention has the following effects compared with the prior art:

[0023] 1. The drive assembly that uses a two-way piston to control torque transmission provided by the present invention. When the first reversing valve is opened, pressure oil is charged into the pressing cavity, generating an axial force in one direction on the pressing piston. When the first reversing valve and the second reversing valve are opened, pressure oil is simultaneously charged into the pressing cavity and the releasing cavity. The pressing piston is subjected to axial forces in two opposite directions, and the two axial forces cancel each other out, thereby reducing the pressing force of the pressing piston. By opening and closing the first reversing valve and the second reversing valve, the combined pressing force of the pressing piston on the friction plate group can be achieved. The control elements used are all switching direction valves, with a simple structure, lower manufacturing cost, and better reliability. BRIEF DESCRIPTION OF THE DRAWINGS

[0024] Figure 1 is the overall structural schematic diagram of the friction clutch of the present invention;

[0025] Figure 2 is Figure 1 the schematic diagram of the state where the pressing cavity and the releasing cavity are filled with pressure oil in

[0026] Figure 3 is Figure 2 the enlarged view at the releasing cavity in

[0027] In the figure: 1. Oil cylinder body; 2. Driving piston; 3. Pressure oil pipeline; 4. Driving shaft; 5. Total oil circuit; 6. Pressing cavity; 7. Releasing cavity; 8. Releasing oil circuit; 9. Pressing oil circuit; 10. First sub-oil circuit; 11. Second sub-oil circuit; 12. First reversing valve; 13. Second reversing valve; 14. Third sub-oil circuit; 15. Third reversing valve; 16. Fourth reversing valve; 17. Releasing piston; 18. Pressing piston; 19. Oil discharge port; 20. Oil drain plug; 21. Friction plate group; 22. External gear ring; 23. Elastic member; 24. Baffle; 25. Friction seat; 26. Installation groove; 27. Elastic retaining ring; 28. Positioning ring. DETAILED DESCRIPTION OF THE INVENTION

[0028] Detailed Embodiment 1: In combination with Figures 1 to 3To describe this embodiment, this embodiment includes an oil cylinder body 1, an oil tank (not shown in the figure), a driving piston 2, and a pressure oil pipeline 3. The oil cylinder body 1 is fixedly installed on the driving shaft 4. The oil cylinder body 1 is axially positioned by the shaft shoulder of the driving shaft 4 and the snap ring 27 installed on the driving shaft 4. The oil cylinder body 1 is connected to the oil tank. The inlet of the main oil path 5 on the pressure oil pipeline 3 is communicated with the oil tank. The driving piston 2 is slidably installed on the driving shaft 4 and the oil cylinder body 1. A pressing cavity 6 is formed between the driving piston 2, the oil cylinder body 1, and the driving shaft 4. A relaxation cavity 7 is formed between the driving piston 2 and the oil cylinder body 1. The driving shaft 4 is provided with a relaxation oil path 8 and a pressing oil path 9. The relaxation oil path 8 is communicated with the relaxation cavity 7. The pressing oil path 9 is communicated with the pressing cavity 6. The pressure oil pipeline 3 includes a main oil path 5, a first branch oil path 10, and a second branch oil path 11. The first branch oil path 10 is communicated with the pressing oil path 9. The second branch oil path 11 is communicated with the relaxation oil path 8 through a rotary seal on the driving shaft 4. A first reversing valve 12 is arranged on the first branch oil path 10. A second reversing valve 13 is arranged on the second branch oil path 11. The outlets of the first reversing valve 12 and the second reversing valve 13 are both communicated with the oil tank.

[0029] It should be noted that for the on-off directional valve that controls the liquid flow direction, the requirement for the filtration accuracy of the oil is lower than that of pressure control valves such as pressure reducing valves, servo valves, and proportional valves that require fine adjustment of the valve port opening. Therefore, the manufacturing cost is relatively low.

[0030] In the driving assembly of this embodiment that uses a two-way piston to control the transmission of torque, when the first reversing valve 12 is opened, pressure oil is filled into the pressing cavity 6, generating an axial force in one direction on the pressing piston 18. When the first reversing valve 12 and the second reversing valve 13 are opened, pressure oil is simultaneously filled into the pressing cavity 6 and the relaxation cavity 7. The pressing piston 18 is subjected to two axial forces in opposite directions, and the two axial forces cancel each other out, thereby reducing the pressing force of the pressing piston 18. By opening and closing the first reversing valve 12 and the second reversing valve 13, the combined pressing force of the pressing piston 18 on the friction plate group 21 can be achieved. The control elements used are all on-off directional valves, with a simple structure, lower manufacturing cost, and better reliability.

[0031] Specific Embodiment 2: In combination with Figure 1 、 Figure 2Describing this embodiment, the difference between this embodiment and the first specific embodiment is that the first reversing valve 12 is a power-off holding electromagnetic reversing valve. The structure of the power-off holding electromagnetic reversing valve is a two-position four-way double-solenoid valve without a return spring. When the open-valve solenoid coil is energized and the close-valve solenoid coil is de-energized, the valve opens. When the open-valve solenoid coil is de-energized and the close-valve solenoid coil is energized, the valve closes. When both electromagnetic coils are de-energized, the spool state before power-off can be maintained through an internal mechanical positioner. The second reversing valve 13 is a hydraulically controlled reversing valve. The hydraulically controlled reversing valve is a two-position three-way hydraulic actuator valve with a return spring. It opens when the control oil pressure is high and automatically resets when the control oil pressure is low. The flow of pressure oil is achieved through the first reversing valve 12 and the second reversing valve 13. Other components and connection relationships are the same as those in the first specific embodiment.

[0032] Specific Embodiment Three: Combining Figure 1 、 Figure 2 Describing this embodiment, the difference between this embodiment and the second specific embodiment is that the pressure oil pipeline 3 further includes: a third branch oil pipeline 14. One end of the third branch oil pipeline 14 is connected to a position on the first branch oil pipeline 10 downstream of the first reversing valve 12, and the other end of the third branch oil pipeline 14 is connected to the control port of the second reversing valve 13. The pressure oil on the third branch oil pipeline 14 flows from the first branch oil pipeline 10 to the second branch oil pipeline 11. A third reversing valve 15 and a fourth reversing valve 16 are arranged on the third branch oil pipeline 14 along the flow direction of the pressure oil. The flow of pressure oil on the third branch oil pipeline 14 is achieved through the third reversing valve 15 and the fourth reversing valve 16 to control the opening and closing of the second reversing valve 13. Other components and connection relationships are the same as those in the second specific embodiment.

[0033] Specific Embodiment Four: Combining Figure 1 、 Figure 2 Describing this embodiment, the difference between this embodiment and the third specific embodiment is that the third reversing valve 15 is a differential pressure check valve. The differential pressure check valve is a check valve with a spring, and its forward flow opening pressure is a fixed value, and reverse flow is not possible. The fourth reversing valve 16 is an automatic reset electromagnetic reversing valve. The structure of the automatic reset electromagnetic reversing valve is a two-position three-way single-solenoid valve with a return spring. The valve opens when the solenoid coil is energized and automatically resets after power-off. Other components and connection relationships are the same as those in the third specific embodiment.

[0034] Specific Embodiment Five: Combining Figure 1 、 Figure 3This embodiment is described. The difference between this embodiment and the first embodiment is that the driving piston 2 includes a release piston 17 and a clamping piston 18 which are fixedly connected. The release piston 17 is slidably mounted on the oil cylinder body 1, and the clamping piston 18 is slidably mounted on the oil cylinder body 1 and the driving shaft 4. In this embodiment, the release piston 17 and the clamping piston 18 can be connected by bolts, or when one of the release piston 17 and the clamping piston 18 is damaged, only the corresponding piston needs to be replaced, and all of them do not need to be replaced, which reduces the maintenance cost. The other components and connection relationships are the same as those of the first embodiment.

[0035] Specific implementation method six: Combination Figure 1 , Figure 2 This embodiment is described. The difference between this embodiment and the fifth embodiment is that the release piston 17 is provided with an oil discharge port 19 for connecting the release chamber 7 with the outside. An oil drain plug 20 is fixedly installed at the oil discharge port 19. The oil drain plug 20 is located at the outer diameter of the release piston 17. After the hydraulic control reversing valve is closed, the residual oil in the release chamber 7 is automatically discharged from the release chamber 7 through the oil drain plug 20 under the action of centrifugal force. When the oil is supplied to the release chamber 7, the liquid flow path of the hydraulic control reversing valve is much larger than the liquid flow path of the oil drain plug 20, so the release chamber 7 can be kept full. The other components and connection relationships are the same as those of the fifth embodiment.

[0036] Specific implementation method seven: Combination Figures 1 to 3 The present embodiment further provides a friction clutch, comprising: a driving shaft 4, a friction plate group 21, an outer gear ring 22, an elastic member 23, and a driving assembly for controlling the transmission of torque using a bidirectional piston, wherein the friction plate group 21 is composed of a plurality of active plates and driven plates that are staggered, wherein the plurality of active plates are key-connected to the driving shaft 4, and the plurality of driven plates are key-connected to the outer gear ring 22, and a baffle plate 24 that protrudes radially outward is fixedly connected to one end of the driving shaft 4, and the baffle plate 24 abuts against one side of the friction plate group 21, and the baffle plate 24 Bolt connection can be adopted between the driving shaft 4, the elastic member 23 is connected with the driving piston 2 of a driving assembly adopting a bidirectional piston to control the transmission of torque, and the elastic member 23 has the elastic force to push the driving piston 2 away from the friction plate group 21. When the pressing chamber 6 of the driving assembly adopting a bidirectional piston to control the transmission of torque is filled with pressure oil, the driving piston 2 overcomes the elastic force of the elastic member 23 and is pressed on the other side of the friction plate group 21. When the pressing chamber 6 and the release chamber 7 are filled with pressure oil, the pressing force becomes smaller and a smaller torque can be transmitted. The other components and connection relationships are the same as any one of the specific embodiments 1 to 6.

[0037] Specific implementation method eight: Combination Figure 1 , Figure 2Description of this embodiment: The difference between this embodiment and the seventh specific embodiment is that the driving shaft 4 has a friction seat 25. Multiple driving plates of the friction plate group 21 are key-connected to the friction seat 25. The friction seat 25 and the driving shaft 4 can be connected by bolts. The positioning ring 28 axially positions the friction seat 25 and the baffle 24 on the driving shaft 4 and is located on the side of the pressing piston 18. The friction seat 25 plays an intermediate connection role, avoiding the direct action of the friction plate group 21 on the driving shaft 4 body, protecting the driving shaft 4 and improving its service life. Other components and connection relationships are the same as those in the seventh specific embodiment.

[0038] Specific embodiment nine: In combination with Figure 1 、 Figure 2 Description of this embodiment: The difference between this embodiment and the eighth specific embodiment is that the friction seat 25 has an installation groove 26 with an opening facing the driving piston 2. One end of the elastic member 23 abuts against the side wall of the installation groove 26, and the other end of the elastic member 23 abuts against the driving piston 2. When the pressure in the pressing cavity 6 is relatively low, the elastic member 23 can push the release piston 17 and the pressing piston 18 to remain in the disengaged position on the left, so that the clutch is in a state of disconnecting torque transmission. Other components and connection relationships are the same as those in the eighth specific embodiment.

[0039] Specific embodiment ten: In combination with Figure 1 、 Figure 2 Description of this embodiment: The difference between this embodiment and the ninth specific embodiment is that the elastic member 23 is a spring. The spring has good elasticity, a long service life, and better use effects. Other components and connection relationships are the same as those in the ninth specific embodiment.

[0040] The working principle of this embodiment:

[0041] The outlets of the power-off holding electromagnetic directional valve, the automatic reset electromagnetic directional valve, and the pilot-operated directional valve are all connected to the oil tank. The differential pressure check valve is closed. The pressing piston 18 and the release piston 17 are not filled with oil. The spring pushes the release piston and the pressing piston 18 to remain in the disengaged position on the left. All friction plates are completely relaxed, and the friction clutch cannot transmit frictional torque.

[0042] When the solenoid coil of the power-off holding electromagnetic directional valve is energized, the power-off holding electromagnetic directional valve opens. Pressure oil enters the pressing cavity 6 and acts on the pressing piston 18. After the axial force generated to the right is greater than the spring pre-tightening force, the pressing piston 18 quickly moves to the right. At the same time, the volume of the release cavity 7 becomes smaller, and the air inside it flows out through the outlet of the pilot-operated directional valve.

[0043] After the pressing cavity 6 is filled with oil, all friction plates are in a pressed state, the pressure oil stops flowing, and the pressure in the pressing cavity 6 starts to automatically increase. The friction clutch has the ability to transmit frictional torque.

[0044] When the automatic reset electromagnetic directional control valve is energized and opened, after the pressure in the pressing chamber 6 automatically rises to the opening pressure of the differential pressure check valve, a path of pressure oil enters the control port of the pilot-operated directional control valve through the differential pressure check valve and the automatic reset electromagnetic directional control valve, causing the pilot-operated directional control valve to open. The pressure oil enters the release chamber 7 through the pilot-operated directional control valve and the release oil circuit 8 and generates an axial force to the left on the release piston 17. At this time, the axial force received by the friction plate group 21 is the difference between the axial forces of the pressing piston 18 and the release piston 17. The clutch can only transmit a relatively small frictional torque, and the clutch realizes soft engagement and disengagement by sliding friction at low torque.

[0045] When the automatic reset electromagnetic directional control valve is de-energized and closed, the pressure at the control port of the pilot-operated directional control valve decreases, the pilot-operated directional control valve closes, the pressure in the release chamber 7 is connected to the oil tank, the axial force generated by the release piston 17 disappears, and the clutch only presses the friction element group under the axial force generated by the pressing piston 18. The clutch can transmit a relatively large rated frictional torque.

[0046] The content of the present invention is not limited to the content of the above embodiments. The combination of one or several specific embodiments can also achieve the purpose of the invention.

Claims

1. A drive assembly that uses a bi-directional piston to control torque transmission, comprising: An oil cylinder body (1), an oil tank, a driving piston (2), and a pressure oil pipeline (3), wherein the oil cylinder body (1) is fixedly installed on a driving shaft (4), the oil cylinder body (1) is connected to the oil tank, and an oil inlet of a main oil path (5) on the pressure oil pipeline (3) is communicated with the oil tank; It is characterized in that the driving piston (2) is slidably installed on the driving shaft (4) and the oil cylinder body (1), a pressing cavity (6) is formed between the driving piston (2), the oil cylinder body (1) and the driving shaft (4), a relaxation cavity (7) is formed between the driving piston (2) and the oil cylinder body (1), a relaxation oil path (8) and a pressing oil path (9) are provided on the driving shaft (4), the relaxation oil path (8) is communicated with the relaxation cavity (7), and the pressing oil path (9) is communicated with the pressing cavity (6); The pressure oil pipeline (3) includes a main oil path (5), a first branch oil path (10), and a second branch oil path (11), the first branch oil path (10) is communicated with the pressing oil path (9), and the second branch oil path (11) is communicated with the relaxation oil path (8); A first reversing valve (12) is provided on the first branch oil path (10), a second reversing valve (13) is provided on the second branch oil path (11), and outlets of the first reversing valve (12) and the second reversing valve (13) are both communicated with the oil tank.

2. The drive assembly for transmitting torque by means of bidirectional piston control according to claim 1, characterized in that, The first reversing valve (12) is a power-off holding electromagnetic reversing valve, and the second reversing valve (13) is a hydraulically controlled reversing valve.

3. A drive assembly for transmitting torque using a bi-directional piston according to claim 2, characterized in that, The pressure oil pipeline (3) further includes: a third branch oil path (14), one end of the third branch oil path (14) is communicated with a position on the first branch oil path (10) downstream of the first reversing valve (12), and the other end of the third branch oil path (14) is communicated with a control port of the second reversing valve (13); On the third branch oil path (14), pressure oil flows from the first branch oil path (10) to the second branch oil path (11), and a third reversing valve (15) and a fourth reversing valve (16) are arranged on the third branch oil path (14) along the flowing direction of the pressure oil.

4. The drive assembly for transmitting torque by bidirectional piston control according to claim 3, characterized in that, The third reversing valve (15) is a differential pressure one-way valve, and the fourth reversing valve (16) is an automatic reset electromagnetic reversing valve.

5. A drive assembly for transmitting torque using a bi-directional piston as claimed in claim 1, wherein, The driving piston (2) includes a relaxation piston (17) and a pressing piston (18) fixedly connected, the relaxation piston (17) is slidably installed on the oil cylinder body (1), and the pressing piston (18) is slidably installed on the oil cylinder body (1) and the driving shaft (4).

6. The drive assembly for transmitting torque by means of bidirectional piston control according to claim 5, characterized in that, An oil discharge port (19) for communicating the relaxation cavity (7) with the outside is provided on the relaxation piston (17), and an oil drain plug (20) is fixedly installed at the oil discharge port (19).

7. A friction clutch, characterized in that, Including: The driving shaft (4), friction plate group (21), external gear ring (22), elastic member (23), and a driving assembly for transmitting torque controlled by a two-way piston according to any one of claims 1-6, a plurality of driving plates of the friction plate group (21) are key-connected to the driving shaft (4), a plurality of driven plates of the friction plate group (21) are key-connected to the external gear ring (22), one end of the driving shaft (4) is fixedly connected with a baffle (24) protruding radially outward, and the baffle (24) abuts against one side of the friction plate group (21); The elastic member (23) is connected to the driving piston (2) of the driving assembly for transmitting torque controlled by a two-way piston, and the elastic member (23) has an elastic force for pushing the driving piston (2) away from the friction plate group (21); When the pressure oil fills the pressing cavity (6) of the driving assembly for transmitting torque controlled by a two-way piston, the driving piston (2) overcomes the elastic force of the elastic member (23) and presses against the other side of the friction plate group (21).

8. A friction clutch according to claim 7, characterized in that, The driving shaft (4) has a friction seat (25), and a plurality of driving plates of the friction plate group (21) are key-connected to the friction seat (25).

9. A friction clutch according to claim 8, characterized in that, The friction seat (25) has a mounting groove (26) with an opening facing the driving piston (2), one end of the elastic member (23) abuts against the side wall of the mounting groove (26), and the other end of the elastic member (23) abuts against the driving piston (2).

10. A friction clutch according to claim 9, characterized in that, The elastic member (23) is a spring.

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