A low-leakage pump control circuit integrated hydraulic module and a hydraulic system

Abstract

The application relates to the technical field of hydraulic systems, and discloses a low-leakage pump control circuit integrated hydraulic module and a hydraulic system. The hydraulic module comprises a main pump control valve, an auxiliary pump control valve, a control oil pipe, an emergency control oil pipe, a main pressure oil pipe group, an auxiliary pressure oil pipe group, a pressure oil connecting pipe group, a two-position three-way hydraulic directional valve and two double-control check valves; the control oil pipe is connected with first control oil input ports of the two double-control check valves; the emergency control oil pipe is connected with second control oil input ports of the two double-control check valves; first pressure oil ports of the two double-control check valves are connected with the main pump control valve and the auxiliary pump control valve; second pressure oil ports of the double-control check valves are connected with the pressure oil connecting pipe group; and the emergency control oil pipe is further connected with the main pump control valve, the auxiliary pump control valve and the two-position three-way hydraulic directional valve. The application can avoid that pressure oil of an actuator leaks from the double-control check valves to the main pump control circuit or the auxiliary pump control circuit, and can avoid affecting working oil pressure of an emergency hydraulic oil circuit.

Description

Technical Field

[0001] This invention relates to the field of hydraulic system technology, and in particular to a low-leakage pump control circuit integrated hydraulic module and hydraulic system. Background Technology

[0002] Dual-pump control circuit switching hydraulic systems are generally used in mechanical equipment to drive specific actions. Currently, such systems typically include a main pump control circuit, a secondary pump control circuit, and an emergency circuit. The main and secondary pump control circuits can switch between each other; if the main pump control circuit fails, the secondary pump control circuit takes over. If both the main and secondary pump control circuits fail, the emergency circuit activates to continue operation.

[0003] In a dual-pump control circuit switching hydraulic system, various components used for switching between the main pump control circuit, auxiliary pump control circuit, and emergency circuit are integrated together to form a dual-pump control circuit switching hydraulic integrated block. This block integrates a hydraulic drive module composed of the main and auxiliary pump control circuits, and an emergency drive module composed of the emergency circuit. The hydraulic drive module and the emergency drive module are two independently operating drive modules; the hydraulic drive module is used for normal operation, and the emergency drive module is used for emergency operations.

[0004] However, in existing dual-pump control circuit switching hydraulic integrated blocks, the control oil in the pilot stage must control both the hydraulic drive module and the emergency drive module to change their working actions. Therefore, the control oil pipelines of the hydraulic drive module and the emergency drive module inevitably have connection points in their structure. This causes the two originally independently operating hydraulic drive module and emergency drive module to connect and cross-connect. For example, when the hydraulic drive module stops working and the emergency drive module starts working, the oil in the hydraulic drive module cross-connects with the oil in the emergency drive module, which affects the driving accuracy of the emergency drive module.

[0005] To address the issue of oil leakage between the hydraulic drive module and the emergency drive module, some manufacturers use spool valves as the main valves in the dual-pump control circuit switching hydraulic integrated block. However, the valve core and valve sleeve of a spool valve are inevitably clearance-fitted, which leads to significant pressure oil leakage and affects the accuracy of the drive action. Summary of the Invention

[0006] To overcome the shortcomings of existing technologies, this invention provides a low-leakage pump control circuit integrated hydraulic module and hydraulic system.

[0007] This invention is achieved using the following technical solution: In some embodiments, a low-leakage pump control circuit integrated hydraulic module is provided. The low-leakage pump control circuit integrated hydraulic module includes: a main pump control valve, a secondary pump control valve, a control oil pipe, an emergency control oil pipe, a main pressure oil pipe assembly, a secondary pressure oil pipe assembly, a pressure oil connecting pipe assembly, a two-position three-way hydraulic directional valve, and two dual-control check valves; the pressure oil connecting pipe assembly is used to connect to the actuator; each dual-control check valve includes a first control oil inlet, a second control oil inlet, a first pressure oil port, and a third... Two pressure oil ports; the control oil pipe is connected to the first control oil input port of each of the two-control check valves, and the emergency control oil pipe is connected to the second control oil input port of each of the two-control check valves; the first pressure oil port of each of the two-control check valves is connected to the main pump control valve and the auxiliary pump control valve, and the second pressure oil port of the two-control check valve is connected to the pressure oil connection pipe group; the emergency control oil pipe is also connected to the main pump control valve, the auxiliary pump control valve, and the two-position three-way hydraulic directional valve, and the two-position three-way hydraulic directional valve is connected to the control oil pipe, the main pump control valve, and the auxiliary pump control valve.

[0008] In some embodiments, the main pressure oil pipe assembly, the main pump control valve, the two double-control check valves, and the pressure oil connecting pipe assembly constitute the main pump control circuit; the auxiliary pressure oil pipe assembly, the auxiliary pump control valve, the two double-control check valves, and the pressure oil connecting pipe constitute the auxiliary pump control circuit; the low-leakage pump control circuit integrated hydraulic module further includes: a two-position four-way solenoid directional valve and a return oil pipe, wherein both the main pump control valve and the auxiliary pump control valve have a third control oil input port and a fourth control oil input port; the emergency control oil pipe is connected to the third control oil input port, and the two-position four-way solenoid directional valve is connected to the fourth control oil input port of the main pump control valve and the auxiliary pump control valve, the two-position three-way hydraulic directional valve, and the return oil pipe.

[0009] In some embodiments, a two-position three-way hydraulic directional valve has a first oil port, a second oil port, a third oil port, and a control oil input port; a two-position four-way solenoid directional valve has a first oil port, a second oil port, a third oil port, and a fourth oil port; a control oil pipe is connected to the first oil port of the two-position three-way hydraulic directional valve, the second oil port of the two-position three-way hydraulic directional valve is connected to the first oil port of the two-position four-way solenoid directional valve, the third oil port of the two-position three-way hydraulic directional valve is connected to the return oil pipe, the second oil port and the third oil port of the two-position four-way solenoid directional valve are respectively connected to the fourth control oil input ports of the main pump control valve and the auxiliary pump control valve, the fourth oil port of the two-position four-way solenoid directional valve is connected to the return oil pipe, and an emergency control oil pipe is connected to the control oil input port of the two-position three-way hydraulic directional valve.

[0010] In some embodiments, there are two control oil pipes, and each control oil pipe is provided with a one-way valve.

[0011] In some embodiments, an overflow valve is provided between each control oil pipe and the return oil pipe.

[0012] In some embodiments, the main pressure oil pipe group includes two main pressure oil pipes, the auxiliary pressure oil pipe group includes two auxiliary pressure oil pipes, and the main pump control valve and the auxiliary pump control valve each have a first oil port, a second oil port, a third oil port, and a fourth oil port; one end of each of the two main pressure oil pipes is connected to the first oil port and the second oil port of the main pump control valve, respectively; one end of each of the two auxiliary pressure oil pipes is connected to the first oil port and the second oil port of the auxiliary pump control valve, respectively; the third oil port of both the main pump control valve and the auxiliary pump control valve is connected to the first pressure oil port of the same double-control check valve, and the fourth oil port of both the main pump control valve and the auxiliary pump control valve is connected to the first pressure oil port of another double-control check valve.

[0013] In some embodiments, the pressure oil connection pipe assembly includes two pressure oil connection pipes, which are respectively connected to the second pressure oil ports of the two dual-control check valves.

[0014] In some embodiments, the dual-control check valve employs a conical seal.

[0015] In some embodiments, the dual-control check valve includes at least a housing, a valve core, a push rod, a valve sleeve, and a valve seat; the housing has a first cavity, a second cavity, a third cavity, and a fourth cavity arranged sequentially and connected along its own axial direction, the portion connecting the second cavity and the third cavity forming a first channel; the portion connecting the third cavity and the fourth cavity forming a second channel; the housing also has a first control oil inlet connecting the first cavity, a second control oil inlet connecting the fourth cavity, a first pressure oil inlet connecting the second cavity, and a second pressure oil inlet connecting the third cavity; the valve sleeve is positioned... In the third cavity, one end of the valve sleeve is inserted into the first channel, and the inner edge of the other end of the port forms a conical groove; the valve seat is located in the third cavity and abuts against the edge of the port of the second channel; a sealing gasket is provided in the circumferential direction of the valve seat, and the valve seat has a through hole aligned with the second channel; the valve core is located in the third cavity, and its end facing the second cavity has a conical wall; the conical wall matches the shape of the conical groove to form a conical surface seal; one end of the push rod is located in the first cavity, and the other end is located in the third cavity and fixed to the valve core.

[0016] In some embodiments, a low-leakage pump-controlled circuit hydraulic system is provided, including an oil tank, a main pressure oil pump, a secondary pressure oil pump, an emergency pressure oil pump, an actuator, and a low-leakage pump-controlled circuit integrated hydraulic module as described in any of the above embodiments; the main pressure oil pump is connected to two main pressure oil pipes; the secondary pressure oil pump is connected to two secondary pressure oil pipes. The low-leakage pump-controlled circuit integrated hydraulic module is an integrated valve body structure with oil ports A, B, K, A1, B1, A2, B2, K1, K2, and O; wherein, oil ports A1 and B1 are connected to the main pressure oil pump of the main pump-controlled circuit, oil ports A2 and B2 are connected to the secondary pressure oil pump of the backup pump-controlled circuit, oil ports A and B are respectively connected to pressure oil connecting pipes and connected to the working oil port of the actuator, oil port K is connected to the emergency circuit control oil port, oil ports K1 and K2 are respectively connected to the main pump-controlled circuit control oil and the backup pump-controlled circuit control oil, and oil port O is connected to the pump-controlled circuit oil tank.

[0017] The beneficial effects of this application include at least the following: Compared with the prior art, the present invention uses a double-control check valve to replace the traditional slide valve structure. When the low-leakage pump control circuit hydraulic system starts emergency hydraulic operation, the emergency control oil pipe inputs pressure oil to the second control oil inlet of the double-control check valve. The pressure oil can drive the valve core to move. With the help of the conical wall of the valve core abutting against the conical groove of the valve sleeve, better sealing performance is obtained, which effectively reduces the amount of pressure oil leaking from the third chamber to the second chamber. This largely avoids the pressure oil of the actuator from leaking from the double-control check valve to the main pump control circuit or the auxiliary pump control circuit, thus avoiding affecting the working oil pressure of the emergency hydraulic circuit. Attached Figure Description

[0018] Figure 1 This is a schematic diagram of the structure of a dual-control check valve according to some embodiments of the present invention.

[0019] Figure 2 This is a schematic diagram of a low-leakage pump control circuit hydraulic system according to some embodiments of the present invention.

[0020] Figure 3 This is a schematic diagram of a low-leakage pump control circuit hydraulic system according to some embodiments of the present invention.

[0021] The diagram is labeled as follows: 10. Double-control check valve; 11. First chamber; 111. First control oil inlet; 12. Second chamber; 121. First pressure oil inlet; 13. Third chamber; 131. Second pressure oil inlet; 14. Fourth chamber; 141. Second control oil inlet; 15. Push rod; 16. Valve core; 17. Valve seat; 18. Valve sleeve; 19. Return spring; 21. Main pump control valve; 22. Main pressure oil pipe; 23. Main pressure oil pump; 31. Auxiliary pump control valve; 32. Auxiliary pressure oil pipe; 33. Auxiliary pressure oil pump; 41. Two-position three-way hydraulic directional valve; 42. Two-position four-way solenoid directional valve; 43. Control oil pipe; 44. Check valve; 45. Relief valve; 50. Actuator; 61. Pressure oil connection pipe; 70. Emergency circuit; 71. Emergency control oil pipe; 80. Oil tank; 81. Return oil pipe. Detailed Implementation

[0022] The present invention will now be further described in conjunction with the accompanying drawings and specific embodiments. It should be noted that, without conflict, the various embodiments or technical features described below can be arbitrarily combined to form new embodiments.

[0023] Please see Figure 1 This embodiment discloses a dual-control check valve 10, which is applied to a pump control circuit. Specifically, it is applied to a low-leakage pump control circuit hydraulic system, which can effectively reduce the amount of pressure oil leakage and reduce the probability of significant oil leakage between the emergency circuit and the pump control circuit.

[0024] The dual-control check valve 10 of this embodiment includes at least a housing, a valve core 16, a push rod 15, a valve sleeve 18, and a valve seat 17. The housing can be a split structure, which includes a cylindrical main body, a left end cap, and a right end cap, with the left end cap and right end cap respectively inserted into and fixed to both ends of the main body.

[0025] The housing has a first cavity 11, a second cavity 12, a third cavity 13 and a fourth cavity 14 arranged and connected in sequence along its own axial direction. The part where the second cavity 12 and the third cavity 13 are connected is the first channel, and the part where the third cavity 13 and the fourth cavity 14 are connected is the second channel.

[0026] The housing also has a first control oil inlet 111 connecting to the first cavity 11, a second control oil inlet 141 connecting to the fourth cavity 14, a first pressure oil inlet 121 connecting to the second cavity 12, and a second pressure oil inlet 131 connecting to the third cavity 13. Specifically, the first control oil inlet 111 is located on the left end cover, the second control oil inlet 141 is located on the right end cover, and the first pressure oil inlet 121 and the second pressure oil inlet 131 are both located on the main body.

[0027] The valve sleeve 18 is located in the third cavity 13, with one end inserted into the first channel and the inner edge of the other end forming a conical groove. Specifically, the valve sleeve 18 and the first channel can be interference-fitted to improve the sealing performance of their insertion. The valve seat 17 is located in the third cavity 13 and abuts against the edge of the second channel. A sealing gasket is provided in the circumferential direction of the valve seat 17, which can improve the sealing performance between the circumferential sidewall of the valve seat 17 and the inner wall of the third cavity 13, reducing the probability of oil leakage. The valve seat 17 has a through hole aligned with the second channel. The valve core 16 is located in the third cavity 13, and its end facing the second cavity 12 has a conical wall. The end of the valve core 16 facing away from the second cavity 12 can be inserted into the through hole of the valve seat 17 and is interference-fitted with the through hole to improve the sealing performance between the through hole and the valve core 16. One end of the push rod 15 is located in the first cavity 11, and the other end is located in the third cavity 13, and is fixed to the valve core 16. The conical wall matches the shape of the conical groove, which can be used to form a conical surface seal.

[0028] This application discloses a low-leakage pump-controlled loop hydraulic system for driving mechanical equipment. It includes an oil tank 80, a main pressure oil pump 23, a secondary pressure oil pump 33, an emergency pressure oil pump (not shown), an actuator 50, and a low-leakage pump-controlled loop integrated hydraulic module. Of course, in addition to the aforementioned components, the low-leakage pump-controlled loop hydraulic system can also incorporate commonly used components in hydraulic transmission, such as pressure sensors, flow sensors, safety valves, etc., according to actual assembly requirements, operational requirements, functional requirements, or other needs. These are not listed here.

[0029] In this embodiment, the oil tank 80 is used to store hydraulic oil. The actuator 50 can be a hydraulic cylinder, and the two oil inlets of the actuator 50 are also connected to two pressure oil connecting pipes 61. The return oil pipe 81 is connected to the oil tank 80.

[0030] The main pressure pump 23 can be a commonly used bidirectional hydraulic pump in the industry, and its two output ports are respectively connected to two main pressure oil pipes 22. Preferably, the auxiliary pressure pump 33 has the same structure as the main pressure pump 23, and its two output ports are connected to two auxiliary pressure oil pipes 32.

[0031] An emergency hydraulic pump (not shown in the diagram) has two output ports connected to the two oil inlets of the actuator 50 via two pipes, each with a check valve. The control oil output port of the emergency hydraulic pump is connected to the emergency control oil pipe 71.

[0032] An oil tank 80, an emergency hydraulic pump (not shown in the figure), and an actuator 50 are sequentially connected to form an emergency circuit 70, which is used to drive the actuator 50 to complete specific actions. Of course, in other embodiments, the emergency circuit 70 can also be equipped with other components commonly used in the field of hydraulic transmission technology, such as functional valves and various sensors, according to actual operating requirements and functional requirements.

[0033] This application also discloses a low-leakage pump control circuit integrated hydraulic module, which can be a standalone cartridge-type integrated block or integrated into the entire low-leakage pump control circuit hydraulic system. Preferably, in this embodiment, the low-leakage pump control circuit integrated hydraulic module is a standalone cartridge-type integrated block, which has the functions of main pump control circuit oil delivery and auxiliary pump control circuit oil delivery. In addition, it also has the function of switching between the main pump control circuit, auxiliary pump control circuit, and emergency oil circuit.

[0034] Please combine Figure 1 and Figure 2 In this embodiment, the low-leakage pump control circuit integrated hydraulic module includes a main pump control valve 21, a secondary pump control valve 31, an emergency control oil pipe 71, a main pressure oil pipe assembly, a secondary pressure oil pipe assembly, a pressure oil connection pipe assembly, and two dual-control check valves 10. In some feasible solutions, all of the above are mounted on a support frame, support plate, or other supporting medium to realize an integrated block. When needed, this integrated block can be connected to other components in the hydraulic system.

[0035] The main pressure oil pipe assembly, main pump control valve 21, two double-control check valves 10 and pressure oil connecting pipe assembly are connected in sequence through pipelines to form the main pump control circuit. Pressure oil flows in sequence through the main pressure oil pipe assembly, main pump control valve 21, two double-control check valves 10 and pressure oil connecting pipe 61.

[0036] The auxiliary pressure oil pipe assembly, auxiliary pump control valve 31, two double-control check valves 10 and pressure oil connection pipe assembly are connected in sequence through pipelines to form an auxiliary pump control circuit. Pressure oil flows in sequence through the auxiliary pressure oil pipe assembly, auxiliary pump control valve 31, two double-control check valves 10 and pressure oil connection pipe assembly.

[0037] When the low-leakage pump control circuit integrated hydraulic module is installed in the relevant hydraulic system, the main pump control circuit is used to supply pressurized oil for operation to the actuator 50, while the auxiliary pump control circuit serves as a backup oil circuit to supply pressurized oil for operation to the actuator 50.

[0038] Emergency control oil pipe 71 is connected to the second control oil inlet 141 of the two double-control check valves 10 via a pipeline, and is used to input pressure oil for control, i.e., emergency circuit control oil, into the second control oil inlet 141. Control oil pipe 43 is connected to the first control oil inlet 111 of the two double-control check valves 10, and is used to input pressure oil for control, i.e., pump control circuit control oil, into the first control oil inlet 111.

[0039] In typical application scenarios, when the main pump control circuit or the auxiliary pump control circuit starts working, the main pump control circuit or the auxiliary pump control circuit simultaneously delivers pressurized oil to the first control oil inlet 111 of the double-control check valve 10 through the control oil pipe 43. The valve core 16 of the double-control check valve 10 abuts against the port of the second channel, closing the second channel and opening the first channel, so the double-control check valve 10 is in the open state. When the emergency circuit intervenes, in addition to supplying pressurized oil to the actuator 50 for operation, the emergency circuit also simultaneously supplies emergency circuit control oil to the second control oil inlet 141 of the double-control check valve 10 through the emergency control oil circuit. This forces the valve core 16 of the double-control check valve 10 to move toward the second chamber 12, thereby closing the first channel and preventing pressurized oil from flowing from the second chamber 12 to the third chamber 13. This closes the double-control check valve 10, blocking the main pump control circuit and the auxiliary pump control circuit, preventing the pressurized oil from the main pump control circuit and the auxiliary pump control circuit from entering the actuator 50, and also preventing the pressurized oil from the actuator 50 and the emergency circuit from flowing to the main pump control circuit and the auxiliary pump control circuit.

[0040] With its high sealing and low leakage dual-control check valve 10, when switching emergency circuits, the probability of pressurized oil flowing back from the dual-control check valve 10 to the main pump control circuit and auxiliary pump control circuit during emergency circuit operation is effectively reduced, thus avoiding serious oil cross-contamination and constituting one of the protective measures to prevent leakage and oil cross-contamination.

[0041] In some embodiments, protective measures are also provided to further prevent pressure oil leakage and cross-contamination in the emergency circuit. The relevant scheme for these protective measures is as follows: the main pump control valve 21 and the auxiliary pump control valve 31 can be two-position four-way hydraulic directional valves, both having a third control oil inlet. The emergency control oil pipe 71 connects the third control oil inlet of the main pump control valve 21 and the third control oil inlet of the auxiliary pump control valve 31.

[0042] When the main pump control circuit and the auxiliary pump control circuit are working, the emergency control oil pipe 71 stops supplying pressure oil for control to the third control oil inlet of the main pump control valve 21 and the auxiliary pump control valve 31. However, when the emergency circuit is activated, it simultaneously supplies pressure oil for control to the third control oil inlet of the main pump control valve 21 and the auxiliary pump control valve 31 via the emergency control oil pipe 71. The main pump control valve 21 and the auxiliary pump control valve 31 block the main pump control circuit and the auxiliary pump control circuit. The main pump control valve 21 and the auxiliary pump control valve 31 constitute a second protective measure, forming a double protection with the double-control check valve 10. Even if the double-control check valve 10 fails or its leak-proof effect is poor, it can also prevent the pressure oil used for operation by the emergency circuit and the actuator 50 from flowing back to the oil passages at the front end of the main pump control valve 21 and the auxiliary pump control valve 31, thus improving the effectiveness of preventing leakage and cross-contamination.

[0043] In some embodiments, the low-leakage pump control circuit integrated hydraulic module integrates structures for switching between the main pump control circuit and the auxiliary pump control circuit. Specifically, the low-leakage pump control circuit integrated hydraulic module also includes a control oil pipe 43 and a switching valve assembly. Both the main pump control valve 21 and the auxiliary pump control valve 31 have a fourth control oil inlet. The control oil pipe 43 connects to the fourth control oil inlets of the main pump control valve 21 and the auxiliary pump control valve 31 via the switching valve assembly. Specifically, the control oil pipe 43 connects to the switching valve assembly via a pipeline to supply pressure oil for control. The switching valve assembly connects to the fourth control oil inlets of the main pump control valve 21 and the auxiliary pump control valve 31 via pipelines. After the control oil pipe 43 supplies pressure oil for control to the switching valve assembly via pipelines, the switching valve assembly, under the automatic control of the hydraulic system's control unit or the manual control of the operator, can selectively direct the pressure oil for control to either the fourth control oil inlet of the main pump control valve 21 or the fourth control oil inlet of the auxiliary pump control valve 31.

[0044] When the pressure oil for control is directed to the fourth control oil inlet of the main pump control valve 21, the main pump control valve 21 opens, and the main pump control circuit operates. However, since there is no pressure oil input to the fourth control oil inlet of the auxiliary pump control valve 31, the auxiliary pump control valve 31 closes, and the auxiliary pump control circuit is idle. Conversely, when the pressure oil for control is directed to the fourth control oil inlet of the auxiliary pump control valve 31, the main pump control valve closes, the main pump control circuit is idle, and the auxiliary pump control valve 31 opens, and the auxiliary pump control circuit operates.

[0045] This embodiment also includes a third protective measure to further prevent pressure oil leakage and cross-contamination in the emergency circuit. The technical solution is as follows: Emergency control oil pipe 71 is connected to a switching valve group via a pipeline. When emergency control oil pipe 71 supplies pressure oil to the switching valve group, it forces the switching valves to prevent control oil pipe 43 from supplying pressure oil to the fourth control oil inlet of the main pump control valve 21 and the auxiliary pump control valve 31. This ensures that the main pump control valve 21 and the auxiliary pump control valve 31 are closed because they do not have control oil input to their respective fourth control oil inlets. This constitutes the third protective measure, which, together with the second protective measure, ensures that the main pump control valve 21 and the auxiliary pump control valve 31 are completely closed. In addition, the first, second and third protective measures together constitute triple protection to ensure that when the emergency circuit intervenes, the main pump control circuit and the auxiliary pump control circuit can be completely cut off, reducing the probability of leakage of the pressure oil used by the emergency circuit and the actuator 50 to the main pump control circuit and the auxiliary pump control circuit, and greatly reducing the degree of oil cross-contamination between the main pump control circuit, the auxiliary pump control circuit and the emergency circuit.

[0046] Specifically, the switching valve group includes a two-position three-way hydraulic directional valve 41 and a two-position four-way solenoid directional valve 42. The two-position three-way hydraulic directional valve 41 has a first port, a second port, a third port, and a control oil input port. The two-position four-way solenoid directional valve 42 has a first port, a second port, a third port, and a fourth port. A control oil pipe 43 connects to the first port of the two-position three-way hydraulic directional valve 41 via a pipeline. The second port of the two-position three-way hydraulic directional valve 41 connects to the first port of the two-position four-way solenoid directional valve 42 via a pipeline. The third port of the two-position three-way hydraulic directional valve 41 connects to the return oil pipe. The second and third ports of the two-position four-way solenoid directional valve 42 connect to the fourth control oil input port of the main pump control valve 21 and the fourth control oil input port of the auxiliary pump control valve 31, respectively. The fourth port of the two-position four-way solenoid directional valve 42 connects to the return oil pipe. Emergency control oil pipe 71 is connected to the control oil input port of two-position three-way hydraulic directional valve 41 via a pipeline.

[0047] When the emergency control oil pipe 71 supplies pressure oil to the control oil inlet of the two-position three-way hydraulic directional valve 41, the pressure oil in the control oil pipe 43 cannot flow to the first oil port of the two-position four-way solenoid directional valve 42.

[0048] When the main pump circuit or the auxiliary pump circuit is working, the emergency control oil pipe 71 stops supplying pressure oil for control to the control oil inlet of the two-position three-way hydraulic directional valve 41. The first oil port and the second oil port of the two-position three-way hydraulic directional valve 41 are connected, and the pressure oil for control can enter the first oil port of the two-position four-way solenoid directional valve 42 through the pipeline via the two-position three-way hydraulic directional valve 41.

[0049] After the control pressure oil is introduced into the first port of the two-position four-way solenoid directional valve 42, it is selectively delivered to the fourth control oil inlet of the main pump control valve 21 and the fourth control oil inlet of the auxiliary pump control valve 31. Specifically, when the two-position four-way solenoid directional valve 42 is de-energized, its first port is connected to its second port, which is connected to the fourth control oil inlet of the main pump control valve 21. Therefore, the control pressure oil can enter the fourth control oil inlet of the main pump control valve 21, causing the main pump control valve 21 to open its main pump control circuit. When the two-position four-way solenoid directional valve 42 is energized, its first port is connected to its third port, which is connected to the fourth control oil inlet of the auxiliary pump control valve 31. Therefore, the control pressure oil can enter the fourth control oil inlet of the auxiliary pump control valve 31, causing the auxiliary pump control valve 31 to open its auxiliary pump control circuit. This scheme enables the switching between the main pump control circuit and the auxiliary pump control circuit.

[0050] When the emergency circuit is activated, it supplies pressure oil for control to the control oil input port of the two-position three-way hydraulic directional valve 41 through the emergency control oil pipe 71. This pressure oil forcibly pushes the two-position three-way hydraulic directional valve 41 to switch, causing the first oil port of the two-position three-way hydraulic directional valve 41 to be cut off from the second oil port, while the second oil port is connected to the third oil port, thereby cutting off the control pressure oil in the control oil pipe 43. Furthermore, the fourth control oil input ports of the main pump control valve 21 and the auxiliary pump control valve 31 can be connected to the return oil pipe 81.

[0051] In some embodiments, the low-leakage pump control circuit integrated hydraulic module further includes a return oil pipe 81, which connects to the third port of the two-position three-way hydraulic directional valve 41 and the fourth port of the two-position four-way solenoid directional valve 42. When the second port and the third port of the two-position three-way hydraulic directional valve 41 are connected, the oil in the main pump control valve 21, the auxiliary pump control valve 31, and related pipelines can flow back to the return oil pipe 81 through the fourth port of the two-position four-way solenoid directional valve 42 and the third port of the two-position three-way hydraulic directional valve 41, and the return oil pipe 81 guides the oil to the oil tank 80.

[0052] Furthermore, there are two control oil pipes 43, each equipped with a one-way valve 44. The main pump control circuit and the auxiliary pump control circuit respectively input pressure oil for control into the two control oil pipes 43. The output end of each control oil pipe 43 is connected to the return oil pipe 81 through an overflow pipe, and the overflow pipe is equipped with an overflow valve 45.

[0053] Specifically, the output ends of the two control oil pipes 43 are connected to the same pipeline, which is connected to the overflow pipe, and this pipeline is connected to the first control oil inlet 111 of the dual-control check valve 10 and the first oil port of the two-position three-way hydraulic directional valve 41 through other branch pipelines. In the embodiments of this application, the two control oil pipes 43 can simultaneously supply pressure oil for control to the first control oil inlet 111 of the dual-control check valve 10 and the first oil port of the two-position three-way hydraulic directional valve 41.

[0054] In the embodiments of this application, the two relief valves 45 can protect the pipelines. When the oil pressure in the pipeline between the control oil pipe 43 and the double-control check valve 10 is too high, or when the oil pressure in the pipeline between the control oil pipe 43 and the two-position three-way hydraulic directional valve 41 is too high, some oil can be discharged through the relief valves 45 and flow back from the relief pipe to the oil tank 80, thus protecting the corresponding pipelines. When one of the relief valves 45 fails, the other relief valve 45 can still work normally, protecting the pipelines.

[0055] In some embodiments, the main pressure oil pipe assembly includes two main pressure oil pipes 22 for supplying pressurized oil for operation to the main pump control valve 21. The auxiliary pressure oil pipe assembly includes two auxiliary pressure oil pipes 32 for supplying pressurized oil for operation to the auxiliary pump control valve 31. Both the main pump control valve 21 and the auxiliary pump control valve 31 have a first port, a second port, a third port, and a fourth port.

[0056] One end of each of the two main pressure oil pipes 22 is connected to the first and second oil ports of the main pump control valve 21, respectively. One end of each of the two auxiliary pressure oil pipes 32 is connected to the first and second oil ports of the auxiliary pump control valve 31, respectively. The third oil ports of both the main pump control valve 21 and the auxiliary pump control valve 31 are connected to the first pressure oil port 121 of the same double-control check valve 10, and the fourth oil ports of both the main pump control valve 21 and the auxiliary pump control valve 31 are connected to the first pressure oil port (121) of another double-control check valve 10.

[0057] The pressure oil connection pipe assembly includes two pressure oil connection pipes 61, which are respectively connected to the second pressure oil ports 131 of two double-control check valves 10, so as to guide the pressure oil for operation to the actuator 50.

[0058] The following is combined with Figure 3 The low-leakage pump control circuit integrated hydraulic module and hydraulic system in some embodiments of this application are further described.

[0059] In some embodiments of this application, the low-leakage pump control circuit integrated hydraulic module includes a main pump control valve 21, a secondary pump control valve 31, a two-position four-way solenoid directional valve 42, a two-position three-way hydraulic directional valve 41, a first check valve 44a, a second check valve 44b, a first relief valve 45a, a second relief valve 45b, a first dual-control check valve 10a, and a second dual-control check valve 10b.

[0060] The first double-control check valve 10a and the second double-control check valve 10b include a pump control circuit end cover, a valve body, a push rod 15, a valve sleeve 18, a valve core 16, a valve seat 17, an emergency circuit end cover, and a return spring 19.

[0061] In the embodiments of this application, there are two overflow valves, with their T ports and P ports connected respectively. The B2 port of the main pump control valve 21 is connected to the B2 port of the auxiliary pump control valve 31 and the A port of the first double-control check valve 10a. The A2 port of the main pump control valve 21 is connected to the A2 port of the auxiliary pump control valve 31 and the A port of the second double-control check valve 10b. The K port of the main pump control valve 21 is connected to the A port of the two-position four-way solenoid directional valve 42, and its A1 port is connected to the B port of the main pump control circuit. The Y port of the main pump control valve 21 is connected to the Y port of the auxiliary pump control valve 31, and the Y port of the two-position three-way hydraulic directional valve 41 is connected to the emergency circuit control oil. The K port of the auxiliary pump control valve 31 is connected to the B port of the two-position four-way solenoid directional valve 42, and its A1 port is connected to the B port of the standby pump control circuit. The B1 port of the standby pump control circuit is connected to the A port of the standby pump control circuit. The P port of the two-position four-way solenoid directional valve 42 is connected to the A port of the two-position three-way hydraulic directional valve 41, and its T port is connected to the T ports of the first relief valve 45a and the second relief valve 45b, and is also connected to the external oil tank. The P port of the two-position three-way hydraulic directional valve 41 is connected to the B ports of the first check valve 44a and the second check valve 44b, the P ports of the first relief valve 45a and the second relief valve 45b, and the K1 ports of the first double-control check valve 10a and the second double-control check valve 10b. The A port of the first check valve 44a is connected to the control oil of the main pump control circuit. The A port of the second check valve 44b is connected to the control oil of the backup pump control circuit. The emergency circuit control oil is connected to the K2 ports of the first double-control check valve 10a and the second double-control check valve 10b, the Y port of the main pump control valve 21, the Y port of the auxiliary pump control valve 31, and the Y port of the two-position three-way hydraulic directional valve 41. The B port of the first double-control check valve 10a is connected to one chamber of the hydraulic cylinder actuator and one end of the emergency circuit, and the B port of the second double-control check valve 10b is connected to the other chamber of the hydraulic cylinder actuator and the other end of the emergency circuit.

[0062] The push rod 15 of the double-control check valve is installed in the valve body. The push rod 15, together with the pump control circuit end cover and the valve body, forms a single-acting cylinder. The rodless chamber on the left end is connected to the control oil port K1 of the pump control circuit, while the rod chamber is connected to the atmosphere. The push rod 15 can act on the valve core 16. The valve sleeve 18, valve core 16, valve seat 17, emergency circuit end cover, and return spring 19 of the double-control check valve constitute an externally controlled check valve structure.

[0063] In some embodiments of this application, the low-leakage pump control circuit integrated hydraulic module is an integrated valve body structure with oil ports A, B, K, A1, B1, A2, B2, K1, K2, and O, respectively. Oil ports A1 and B1 are connected to the working oil ports A and B of the main pump control circuit, thereby connecting to the hydraulic pump of the main pump control circuit, i.e., the main pressure oil pump 23. Oil ports A2 and B2 are connected to the working oil ports A and B of the backup pump control circuit, thereby connecting to the hydraulic pump of the backup pump control circuit, i.e., the auxiliary pressure oil pump 33. Oil ports A and B are respectively connected to pressure oil connecting pipes, thereby connecting to the working oil ports of the actuator 50. In some embodiments, the actuator 50 is a hydraulic cylinder actuator. Oil port K is connected to the emergency circuit control oil port. When the emergency circuit stops working, the pressure at this oil port is connected to the oil tank; when the emergency circuit is working, high-pressure oil is supplied. Oil ports K1 and K2 are connected to the control oil of the main and backup pump control circuits, respectively. Oil port O is a pressureless return oil port, connected to the pump control circuit oil tank. Some embodiments of this application adopt an integrated valve body structure, which has a high degree of structural integration and is convenient to use and maintain.

[0064] The working principle of the low-leakage pump control circuit integrated hydraulic module and hydraulic system in this application embodiment is as follows.

[0065] When the main pump control circuit is working, pressure oil supplied by the main pump control circuit enters port K1. This pressure oil passes through the first check valve 44a, the two-position three-way hydraulic directional valve 41, and the two-position four-way solenoid directional valve 42, and enters the left control chamber K port of the main pump control valve 21. The main pump control valve 21 switches to the left position. Under the pressure of port K1, the first double-control check valve 10a and the second double-control check valve 10b overcome the spring force and the pressure of port K. At this time, the pressure of port K is close to 0 and is in the open state. Ports A1 and A are connected, and ports B1 and B are connected. The low-leakage pump control circuit integrated hydraulic module works in the state of driving the hydraulic cylinder actuator in the main pump control circuit. At this time, the right control chamber K port of the auxiliary pump control valve 31 is connected to port O through the two-position four-way solenoid directional valve 42, and is in the left position shown in the figure, i.e., the backup pump control circuit self-bypass state.

[0066] When the two-position four-way solenoid directional valve 42 is energized, it switches to the right position shown in the diagram. The left control chamber K port of the main pump control valve 21 is connected to port O through the two-position four-way solenoid directional valve 42, which is the right position shown in the diagram, i.e., the self-bypass state of the main pump control circuit. At this time, the standby pump control circuit undergoes the same process as described above, with port A2 connected to port A and port B2 connected to port B. The low-leakage pump control circuit integrated hydraulic module operates in the standby pump control circuit driving hydraulic cylinder actuator state.

[0067] When the emergency circuit is working, the emergency circuit control oil enters the K port of the low-leakage pump control circuit integrated hydraulic module, driving the two-position three-way hydraulic directional valve 41 to switch to the right position. The left control chamber K port of the main pump control valve 21 and the right control chamber K port of the auxiliary pump control valve 31 are both connected to the return oil O. The emergency circuit control oil enters the spring reset chamber of the main pump control valve 21 and the auxiliary pump control valve 31 through the K port, driving the main pump control valve 21 and the auxiliary pump control valve 31 to switch to the pump control circuit self-bypass state, ensuring that both the main and backup pump control circuits are in the bypass state. At the same time, the emergency circuit control oil pressure pushes the first double-control check valve 10a and the second double-control check valve 10b to close, isolating and cutting off A1 port with A port, B1 port with B port, A2 port with A port, and B2 port with B port, and the pump control circuit is completely isolated.

[0068] In the embodiments of this application, the first oil port, second oil port, third oil port, and control oil input port of the two-position three-way hydraulic directional valve 41 are respectively the P, A, T, and Y ports of the two-position three-way hydraulic directional valve 41. The first oil port, second oil port, third oil port, and fourth oil port of the two-position four-way solenoid directional valve 42 are respectively the P, A, B, and T ports of the two-position four-way solenoid directional valve 42.

[0069] The working principle of a dual-control check valve is as follows.

[0070] like Figure 1 and 2 As shown, when the pump control circuit is working, there is no pressure at port K2 of the double-control check valve. The control oil of the pump control circuit reaches port K1 of the double-control check valve. The pressure oil pushes the push rod 15 to move to the right against the return spring 19, and the valve core 16 disengages from the valve sleeve 18. The hydraulic oil of the pump control circuit can flow from port A to port B of the double-control check valve. At this time, the hydraulic oil of the pump control circuit can supply oil to the hydraulic cylinder actuator. When the emergency circuit is working, high-pressure oil flows through port K2 of the double-control check valve. The pressure at port K2 of the double-control check valve is higher than the pressure at port K1. The pressure oil acts on the valve core 16. Under this condition, the valve core 16 is in contact with the valve sleeve 18, and the ports A and B of the double-control check valve are closed. The pump control circuit is cut off. Since the valve core 16 and the valve sleeve 18 are sealed with a cone seal, the leakage between ports A and B of the double-control check valve is very low when the emergency circuit is working.

[0071] Specifically, the working process of the dual-control check valve includes: when the emergency circuit drives the actuator 50 to work, the emergency circuit control oil enters the fourth chamber 14 through the second control oil inlet 141. The emergency circuit control oil can push the valve core 16 toward the second chamber 12, so that the conical wall of the valve core 16 is in close contact with the conical groove of the valve sleeve 18. Thus, the valve sleeve 18 and the valve core 16 together close the first channel, cut off the pressure oil delivery path between the second chamber 12 and the third chamber 13, thereby cutting off the oil circuit between the actuator 50 and the pump control circuit. This prevents the pressure oil used for the operation of the emergency circuit from leaking into the pump control circuit through the actuator 50 and the dual-control check valve 10, thus avoiding affecting the operation accuracy of the actuator 50 driven by the emergency circuit.

[0072] When the pump control circuit drives the actuator 50 to work, the emergency circuit is in a stopped oil supply state. When the pressure oil supplied by the pump control circuit enters the first chamber 11 through the first control oil inlet 111, the pressure oil pushes the valve core 16 away from the first channel through the push rod 15, making the first channel open, and causing the valve core 16 to be inserted into the through hole of the valve seat 17 to abut and close the second channel. In this way, the pressure oil used for operation by the pump control circuit can flow sequentially through the first pressure oil port 121, the second chamber 12, the first channel, the third chamber 13, and the second pressure oil port 131 of the double-control check valve 10, and finally enter the actuator 50 through the oil port, driving the actuator 50 to perform the corresponding action.

[0073] Compared with the prior art, this embodiment uses a dual-control check valve 10 instead of a traditional slide valve to connect the actuator 50. When the emergency circuit is working, the valve core 16 and valve sleeve 18 of the dual-control check valve 10 highly seal the first channel through a tapered wall and tapered groove, thereby reducing the probability of pressure oil in the emergency circuit leaking into the pump control circuit through the flow path of the actuator 50, the second pressure port of the dual-control check valve 10, the third chamber 13, the first channel, the second chamber 12, and the first pressure port. Similarly, when the pump control circuit is working, the valve core 16 of the dual-control check valve 10 can be inserted into the through hole of the valve seat 17, abutting and sealing the port of the second channel, thereby highly sealing the second channel and reducing the probability of pressure oil in the pump control circuit leaking from the second channel.

[0074] In some embodiments, the dual-control check valve 10 further includes a return spring 19. One end of the return spring 19 abuts against the inner wall of the fourth chamber 14 away from the second chamber 12, and the other end abuts against the valve core 16. When the pressure oil is stopped being input at the first control oil inlet 111, the deformation force of the return spring 19 forces the valve core 16 to move toward the valve sleeve 18 to close the first passage.

[0075] The above embodiments are merely preferred embodiments of the present invention and should not be construed as limiting the scope of protection of the present invention. Any non-substantial changes and substitutions made by those skilled in the art based on the present invention shall fall within the scope of protection claimed by the present invention.

Claims

1. A low-leakage pump control circuit integrated hydraulic module, characterized in that, The low-leakage pump control circuit integrated hydraulic module includes: Main pump control valve (21), auxiliary pump control valve (31), control oil pipe (43), emergency control oil pipe (71), main pressure oil pipe group, auxiliary pressure oil pipe group, pressure oil connection pipe group, two-position three-way hydraulic directional valve (41) and two double-control check valves (10). The pressure oil connection pipe assembly is used to connect the actuator; Each of the dual-control check valves (10) includes a first control oil inlet (111), a second control oil inlet (141), a first pressure oil inlet (121), and a second pressure oil inlet (131). The control oil pipe (43) is connected to the first control oil inlet (111) of each of the dual-control check valves (10), and the emergency control oil pipe (71) is connected to the second control oil inlet (141) of each of the dual-control check valves (10); the first pressure oil port (121) of each of the dual-control check valves (10) is connected to the main pump control valve (21) and the auxiliary pump control valve (31), and the second pressure oil port (131) of the dual-control check valve (10) is connected to the pressure oil connection pipe assembly; The main pump control valve (21) and the auxiliary pump control valve (31) both have a third control oil inlet and a fourth control oil inlet. The emergency control oil pipe (71) is connected to the third control oil inlet. The two-position three-way hydraulic directional valve (41) has a control oil inlet. The emergency control oil pipe (71) is connected to the control oil inlet of the two-position three-way hydraulic directional valve (41). The two-position three-way hydraulic directional valve (41) is connected to the control oil pipe (43), the main pump control valve (21), and the auxiliary pump control valve (31). When the emergency circuit is activated, in addition to supplying pressurized oil to the actuator for operation, the emergency circuit also supplies emergency circuit control oil to the second control oil inlet of the dual-control check valve through the emergency control oil circuit, thereby closing the dual-control check valve and blocking the main pump control circuit and the auxiliary pump control circuit.

2. The low-leakage pump control circuit integrated hydraulic module as described in claim 1, characterized in that, The main pressure oil pipe assembly, the main pump control valve (21), the two double-control check valves (10), and the pressure oil connecting pipe assembly constitute the main pump control circuit; the auxiliary pressure oil pipe assembly, the auxiliary pump control valve (31), the two double-control check valves (10), and the pressure oil connecting pipe assembly constitute the auxiliary pump control circuit. The low-leakage pump control circuit integrated hydraulic module also includes: a two-position four-way solenoid directional valve (42) and a return oil pipe (81). The two-position four-way solenoid directional valve (42) is connected to the fourth control oil inlet of the main pump control valve (21) and the auxiliary pump control valve (31), the two-position three-way hydraulic directional valve (41), and the return oil pipe (81).

3. The low-leakage pump control circuit integrated hydraulic module as described in claim 2, characterized in that, The two-position three-way hydraulic directional valve (41) has a first oil port, a second oil port, and a third oil port; the two-position four-way solenoid directional valve (42) has a first oil port, a second oil port, a third oil port, and a fourth oil port; the control oil pipe (43) is connected to the first oil port of the two-position three-way hydraulic directional valve (41), the second oil port of the two-position three-way hydraulic directional valve (41) is connected to the first oil port of the two-position four-way solenoid directional valve (42), the third oil port of the two-position three-way hydraulic directional valve (41) is connected to the return oil pipe, the second oil port and the third oil port of the two-position four-way solenoid directional valve (42) are respectively connected to the fourth control oil input port of the main pump control valve (21) and the auxiliary pump control valve (31), and the fourth oil port of the two-position four-way solenoid directional valve (42) is connected to the return oil pipe.

4. The low-leakage pump control circuit integrated hydraulic module as described in claim 3, characterized in that, There are two control oil pipes (43), and each control oil pipe (43) is equipped with a one-way valve (44).

5. The low-leakage pump control circuit integrated hydraulic module as described in claim 4, characterized in that, Each control oil pipe (43) is provided with an overflow valve (45) between it and the return oil pipe (81).

6. The low-leakage pump control circuit integrated hydraulic module as described in claim 5, characterized in that, The main pressure oil pipe group includes two main pressure oil pipes (22), the auxiliary pressure oil pipe group includes two auxiliary pressure oil pipes (32), and the main pump control valve (21) and the auxiliary pump control valve (31) each have a first oil port, a second oil port, a third oil port and a fourth oil port; One end of each of the two main pressure oil pipes (22) is connected to the first oil port and the second oil port of the main pump control valve (21); one end of each of the two auxiliary pressure oil pipes (32) is connected to the first oil port and the second oil port of the auxiliary pump control valve (31); the third oil ports of the main pump control valve (21) and the auxiliary pump control valve (31) are both connected to the first pressure oil port (121) of the same double-control check valve (10); the fourth oil ports of the main pump control valve (21) and the auxiliary pump control valve (31) are both connected to the first pressure oil port (121) of another double-control check valve (10).

7. The low-leakage pump control circuit integrated hydraulic module as described in claim 6, characterized in that, The pressure oil connection pipe assembly includes two pressure oil connection pipes (61), and the two pressure oil connection pipes (61) are respectively connected to the second pressure oil port (131) of the two dual-control check valves (10).

8. The low-leakage pump control circuit integrated hydraulic module as described in claim 1, characterized in that, The dual-control check valve uses a conical seal.

9. The low-leakage pump control circuit integrated hydraulic module as described in claim 8, characterized in that, The dual-control check valve includes at least a housing, a valve core (16), a push rod (15), a valve sleeve (18), and a valve seat (17); the housing has a first cavity (11), a second cavity (12), a third cavity (13), and a fourth cavity (14) arranged sequentially and connected along its own axial direction, the part connecting the second cavity (12) and the third cavity (13) is a first channel; the part connecting the third cavity (13) and the fourth cavity (14) is a second channel; the housing also has a first control oil inlet (111) connecting the first cavity (11), a second control oil inlet (141) connecting the fourth cavity (14), a first pressure oil inlet (121) connecting the second cavity (12), and a second pressure oil inlet (141) connecting the third cavity (13). 131); The valve sleeve (18) is located in the third cavity (13), one end of the valve sleeve (18) is inserted into the first channel, and the inner edge of the port of the other end forms a conical groove; The valve seat (17) is located in the third cavity (13) and abuts against the port edge of the second channel; A sealing gasket is provided in the circumferential direction of the valve seat (17), and the valve seat (17) has a through hole aligned with the second channel; The valve core (16) is located in the third cavity (13), and one end of it facing the second cavity (12) has a conical wall; The conical wall matches the shape of the conical groove to form a conical surface seal; One end of the push rod (15) is located in the first cavity (11), and the other end is located in the third cavity (13) and fixed to the valve core (16).

10. A low-leakage pump-controlled circuit hydraulic system, characterized in that, It includes an oil tank (80), a main pressure oil pump (23), a secondary pressure oil pump (33), an actuator (50), and a low-leakage pump control circuit integrated hydraulic module as described in any one of claims 1-9; The low-leakage pump control circuit integrated hydraulic module adopts an integrated valve body structure and has oil ports A, B, K, A1, B1, A2, B2, K1, K2, and O; Among them, oil ports A1 and B1 are connected to the main pressure oil pump of the main pump control circuit, oil ports A2 and B2 are connected to the auxiliary pressure oil pump of the auxiliary pump control circuit, oil ports A and B are respectively connected to the pressure oil connection pipe and connected to the working oil port of the actuator, oil port K is connected to the emergency circuit control oil port, oil ports K1 and K2 are respectively connected to the control oil of the main pump control circuit and the control oil of the auxiliary pump control circuit, and oil port O is connected to the pump control circuit oil tank.

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