A cam variable pump control system

Abstract

The present invention discloses a cam variable pump control system, comprising a bidirectional variable pump, a variable cylinder, a reversing valve, and a cam drive mechanism. The bidirectional variable pump includes a rotatably mounted swing cylinder, which is used to control the bidirectional variable pump to supply hydraulic oil to a hydraulic actuator. The variable cylinder assembly includes a first variable cylinder and a second variable cylinder, wherein the telescopic ends of the first variable cylinder and the second variable cylinder are respectively rotatably connected to opposite ends of the swing cylinder and are disposed on either side of the swing cylinder's rotation point. The reversing valve has a first conduction position and a second conduction position, and the valve core of the reversing valve switches between the first and second conduction positions based on the rotation of the cam. The present invention directly switches the working position of the reversing valve through the cam drive mechanism, thereby reducing the number of control elements for large-displacement pumps in large systems, reducing the number of control valve bodies, and reducing the interference of flow pulsation caused by valve opening and closing or operating mode switching in the hydraulic circuit on the system, thereby improving the stability of the system.

Description

Technical Field

[0001] The present invention belongs to the technical field of variable pumps, and in particular relates to a cam variable pump control system. Background Art

[0002] As the most widely used core power element in hydraulic systems, plunger pumps rely on the reciprocating motion of the plunger in the cylinder and the volumetric changes caused by the angle of the cylinder's moving circle relative to the input shaft to achieve changes in suction and pressure. A common way to change displacement in plunger pumps is by controlling the swash plate. Existing variable displacement methods for plunger pumps mostly control the cylinder angle by controlling the swash plate or the swash shaft. These two components are often controlled by valves, making them susceptible to external interference, particularly flow pulsation in the entire circuit, which is particularly common in large, high-load equipment. Summary of the Invention

[0003] The purpose of the present invention is to provide a cam variable pump control system to solve the problems existing in the above-mentioned prior art.

[0004] To achieve the above object, the present invention provides a cam variable pump control system, comprising:

[0005] a bidirectional variable displacement pump, the bidirectional variable displacement pump including a rotatably arranged swing cylinder, the swing cylinder being used to control the bidirectional variable displacement pump to supply hydraulic oil to the hydraulic actuator;

[0006] A variable cylinder assembly, the variable cylinder assembly comprising a first variable cylinder and a second variable cylinder, wherein the telescopic end of the first variable cylinder and the telescopic end of the second variable cylinder are respectively rotatably connected to two opposite ends of the swing cylinder and are respectively arranged on both sides of the swing cylinder rotation point;

[0007] A reversing valve is provided with an oil inlet end and an oil outlet end, and the reversing valve is connected to the first variable cylinder and the second variable cylinder; the valve core of the reversing valve has at least a first conducting position and a second conducting position:

[0008] When the valve core of the reversing valve is in the first conducting position, the first variable cylinder is connected to the oil inlet end, and the second variable cylinder is connected to the oil outlet end;

[0009] When the valve core of the reversing valve is in the second conducting position, the first variable cylinder is connected to the oil outlet end, and the second variable cylinder is connected to the oil inlet end;

[0010] A cam driving mechanism includes a cam and a cam driving element. The cam driving element drives the cam to rotate, and based on the rotation of the cam, the valve core of the reversing valve is switched between the first conducting position and the second conducting position.

[0011] Optionally, the cam drive mechanism also includes a cam variable rod, which is rotationally connected to the valve core of the reversing valve; based on the rotation of the cam, the cam variable rod swings within a preset plane, so that the valve core of the reversing valve switches between the first conduction position and the second conduction position.

[0012] Optionally, the cam driving element includes a camshaft, which is detachably connected to the cam, and the cam spirally extends along its own axis to form a guide groove. The cam and the cam variable rod are rotatably connected in the guide groove, and the camshaft is driven by a motor.

[0013] Optionally, it also includes a rotating flange, which is detachably connected to the swing cylinder, and the telescopic end of the first variable cylinder and the telescopic end of the second variable cylinder are both rotatably connected to the rotating flange, and the telescopic end of the first variable cylinder and the telescopic end of the second variable cylinder are respectively arranged on both sides of the rotation point of the swing cylinder and the rotating flange.

[0014] Optionally, a sliding groove is provided at one end of the cam variable rod away from the cam driving element, and the rotating flange is rotatably connected to a pin shaft, and the pin shaft is movably arranged in the sliding groove.

[0015] Optionally, the reversing valve is a three-position four-way reversing valve, and the three-position four-way reversing valve includes a first conducting position, an intermediate position, and a second conducting position:

[0016] When the three-position four-way reversing valve is in the first conducting position, the first variable cylinder is connected to the oil inlet end, and the second variable cylinder is connected to the oil outlet end;

[0017] When the three-position four-way reversing valve is in the middle position, no hydraulic oil flows between the first variable cylinder and the second variable cylinder;

[0018] When the three-position four-way reversing valve is in the second conducting position, the first variable cylinder is connected to the oil outlet end, and the second variable cylinder is connected to the oil inlet end.

[0019] Optionally, it also includes:

[0020] a low-pressure relief valve, wherein the inlet of the low-pressure relief valve is connected to the oil circuit between the oil inlet end and the reversing valve;

[0021] A one-way valve, wherein the oil inlet end of the one-way valve is connected to the oil outlet end of the low-pressure relief valve, and the oil outlet end of the one-way valve is connected to the oil outlet pipeline of the bidirectional variable pump.

[0022] Optionally, the hydraulic actuator is a bidirectional variable motor.

[0023] Compared with the prior art, the present invention has the following advantages and technical effects:

[0024] The cam variable pump control system provided by the present invention realizes the switching between the first and second conducting positions of the reversing valve core through the rotation of the cam drive mechanism. When the reversing valve core is in different conducting positions, the oil inlet and outlet of the first variable cylinder and the second variable cylinder change, thereby pushing the telescopic end of the first variable cylinder and the telescopic end of the second variable cylinder to extend or retract. Since the telescopic ends of the first variable cylinder and the second variable cylinder are respectively arranged on both sides of the swing cylinder rotation point, the telescopic ends of the first variable cylinder and the second variable cylinder push the swing cylinder to rotate, thereby controlling the flow direction and flow rate of hydraulic oil supplied by the bidirectional variable pump to the hydraulic actuator. The present invention directly switches the working position of the reversing valve through the cam drive mechanism, reduces the number of control elements for large-displacement pumps in large systems, reduces the number of control valve bodies, reduces the interference of flow pulsation caused by valve opening and closing or working mode switching in the hydraulic circuit on the valve, reduces the interference of the valve on the system, and increases the stability of the system. BRIEF DESCRIPTION OF THE DRAWINGS

[0025] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the following briefly introduces the drawings required for use in the embodiments. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying any creative work.

[0026] Figure 1 This is a schematic diagram of the structure of the cam variable pump control system of the present invention;

[0027] Figure 2 This is a schematic diagram of the first arrangement of the system structure of the present invention;

[0028] Figure 3 This is a schematic diagram of the second arrangement of the system structure of the present invention.

[0029] Among them, 1. bidirectional variable pump, 2. first variable cylinder, 21. first variable piston, 3. second variable cylinder, 31. second variable piston, 4. reversing valve, 51. cam variable rod, 52. camshaft, 53. cam, 54. motor, 55. mounting seat, 56. pin shaft, 6. rotating flange, 7. low-pressure relief valve, 8. one-way valve, 9. bidirectional variable motor. DETAILED DESCRIPTION

[0030] It should be noted that, unless there is a conflict, the embodiments of the present invention and the features of the embodiments may be combined with each other. The embodiments described are only some of the embodiments of the present invention, not all of them. All other embodiments obtained by those of ordinary skill in the art without creative work are within the scope of protection of the present invention. The present invention will be described in detail below with reference to the accompanying drawings and in conjunction with the embodiments.

[0031] like Figure 1-Figure 3 As shown, the present invention provides a cam variable pump control system, which includes a bidirectional variable pump 1, a variable cylinder, a reversing valve 4 and a cam driving mechanism.

[0032] The bidirectional variable pump 1 includes a rotatably arranged swing cylinder, which is used to control the bidirectional variable pump 1 to supply hydraulic oil to the hydraulic actuator; the variable cylinder assembly includes a first variable cylinder 2 and a second variable cylinder 3, and the telescopic end of the first variable cylinder 2 and the telescopic end of the second variable cylinder 3 are respectively rotatably connected to the two opposite ends of the swing cylinder and are arranged on both sides of the rotation point of the swing cylinder; the reversing valve 4 is provided with an oil inlet end and an oil outlet end, and the reversing valve 4 is connected to the first variable cylinder 2 and the second variable cylinder 3.

[0033] The valve core of the reversing valve 4 has at least a first conducting position and a second conducting position: when the valve core of the reversing valve 4 is in the first conducting position, the first variable cylinder 2 is connected to the oil inlet end, and the second variable cylinder 3 is connected to the oil outlet end; when the valve core of the reversing valve 4 is in the second conducting position, the first variable cylinder 2 is connected to the oil outlet end, and the second variable cylinder 3 is connected to the oil inlet end; the cam driving mechanism, the cam driving mechanism includes a cam 53 and a cam driving element, the cam driving element drives the cam 53 to rotate, and based on the rotation of the cam 53, the valve core of the reversing valve 4 is switched between the first conducting position and the second conducting position.

[0034] The cam variable pump control system provided by the present invention uses a cam drive element to rotate a cam, switching the spool of a reversing valve between a first and second conducting position. When the spool of the reversing valve is in different conducting positions, the oil flow in and out of the first and second variable cylinders changes, thereby pushing the telescopic ends of the first and second variable cylinders 2 and 3 to extend or retract. Because the telescopic ends of the first and second variable cylinders 2 and 3 are located on either side of the pivot point of the swing cylinder, these ends push the swing cylinder to rotate, thereby controlling the direction and flow rate of hydraulic oil supplied by the bidirectional variable pump to the hydraulic actuator. By directly switching the working position of the reversing valve through the cam drive mechanism, the present invention reduces the number of control components required for large-displacement pumps in large systems, reduces the number of control valve bodies, and minimizes the interference of flow pulsation caused by valve opening and closing or operating mode switching in the hydraulic circuit on the system, thereby improving system stability. The highly integrated system saves space and is easily installed on the vehicle.

[0035] The cam drive mechanism can use a cam to directly drive the reversing valve 4 to move, or the cam can drive other components to move and then drive the reversing valve 4 to move, so as to switch the valve core of the reversing valve 4 between the first conduction position and the second conduction position. When the cam directly drives the reversing valve 4 to move, the following structure can be adopted: the cam drive mechanism includes a drive motor, the output shaft of the drive motor is detachably connected to a camshaft, a cam is mounted on the camshaft, the cam adopts a shape with different aspect ratios, such as an elliptical structure, and the outer circumference of the cam is provided with grooves with different aspect ratios, such as an elliptical groove, a sliding member is embedded in the groove and slidably connected, the sliding member is rotatably connected to the valve core of the reversing valve, the valve core is slidably arranged inside the reversing valve, the plane where the sliding member is located is in the same plane as the plane where the valve core moves, and the cam is arranged on one side of the reversing valve, and the reversing valve is detachably connected to the entire device. During operation, the camshaft is driven to rotate by the driving motor, which in turn drives the cam to rotate. Since grooves with different length-to-width ratios are opened on the circumference of the outer periphery of the cam, the rotation of the cam drives the sliding part and the valve core to slide, and the sliding direction is consistent with the sliding direction of the valve core and the reversing valve, thereby realizing the switching of the reversing valve between the first conduction position and the second conduction position.

[0036] Preferably, when the cam drives other components to move, thereby driving the reversing valve 4, the cam drive mechanism further includes a cam variable rod 51, which is rotatably connected to the valve core of the reversing valve 4. Based on the rotation of the cam 53, the cam variable rod 51 swings within a predetermined plane, causing the valve core of the reversing valve 4 to switch between a first conduction position and a second conduction position. Because the reversing valve is rotatably mounted within the system, the reversing valve can rotate relative to the valve core, causing the valve core and the reversing valve 4 to shift, accommodating the positional changes caused by the rotation of the cam variable rod 51 and ensuring normal rotation of the cam variable rod 51. The cam drive element drives the cam variable rod 51 to rotate. Since the valve core is slidably mounted within the reversing valve 4, the cam variable rod 51 drives the valve core to move within the reversing valve 4, thereby switching the reversing valve between the first conduction position and the second conduction position. In this embodiment, the valve core is fixedly connected to a drive rod, one end of which is rotatably connected to a pin 56. The pin 56 is rotatably connected to the cam variable rod 51, thereby achieving a rotational connection between the valve core and the cam variable rod 51. Of course, the rotational connection between the valve core and the cam variable rod 51 can also be achieved in other ways. For example, the valve core is fixedly connected to a drive bracket, and the drive bracket is parallel to the valve core movement plane, that is, the drive bracket and the valve core movement plane are in two parallel planes. The drive bracket and the cam variable rod 51 are rotationally connected through a pin shaft 56 or other components to ensure that the cam variable rod 51 can switch the working position of the reversing valve 4.

[0037] The cam driving element can choose direct drive or indirect drive to realize the rotation of the cam variable rod 51; for example, when the cam driving element chooses indirect drive, the cam driving element includes a motor, the output shaft of the motor is detachably connected to the camshaft, and the camshaft is detachably connected to the cam, and other transmission mechanisms such as a deflection wheel and a connecting rod are arranged between the cam and the cam variable rod 51 to convert the rotational motion of the cam into the rotational motion of the cam variable rod 51, and the cam variable rod 51 can only rotate within the valve core moving plane.

[0038] In a further optimized solution, the cam drive element includes a camshaft 52, which is detachably connected to a cam 53. A guide groove is formed on the circumference of the cam 53 along its axis, and the cam 53 is rotatably connected to the cam variable rod 51 within the guide groove. The camshaft 52 is driven by a motor 54. The motor 54 rotates the camshaft 52, which in turn drives the cam. Because the cam 53 and the cam variable rod 51 are rotatably connected within the guide groove, which is annular and obliquely arranged around the circumference of the cam 53, and the cam variable rod 51 is rotatably connected to the valve core of the reversing valve 4, the cam variable rod 51 is positionally restricted, ensuring that it can rotate only within the plane of movement of the valve core. Direct drive reduces the number of drive components, resulting in more sensitive drive and easier operation. Preferably, one end of the camshaft 52 is detachably connected to the output shaft of the motor 54 via a coupling, while the other end is rotatably connected to the mounting base 55 via a bearing, ensuring that the camshaft 52 can rotate only along its axis.

[0039] A further optimized solution is provided, in which a cam variable pump control system further includes a rotating flange 6, which is detachably connected to the swivel cylinder. The telescopic ends of the first variable cylinder 2 and the second variable cylinder 3 are both rotatably connected to the rotating flange 6, and the telescopic ends of the first variable cylinder 2 and the second variable cylinder 3 are respectively arranged on both sides of the rotation point of the swivel cylinder and the rotating flange 6. The rotating flange 6 is rigidly connected to the swivel cylinder by nuts or screws, so that the rotating flange 6 and the swivel cylinder can move synchronously, that is, the rotating flange 6 and the swivel cylinder can rotate synchronously about the swivel cylinder rotation point, and the telescopic ends of the first variable cylinder 2 and the second variable cylinder 3 are respectively rotatably connected to the rotating flange 6 and are respectively arranged on both sides of the rotation point, ensuring that the changes in the oil inlet and outlet of the first variable cylinder 2 and the second variable cylinder 3 can cause the rotating flange 6 to rotate, thereby driving the rotation of the swivel cylinder.

[0040] A further optimization scheme features a sliding groove on the end of the cam variable rod 51 facing away from the cam drive element. A pin 56 is rotatably connected to the rotating flange 6, which is movably disposed within the sliding groove. The cam drive element rotates the cam variable rod 51, and the oil flow in and out of the first and second variable cylinders 2 and 3 drives the rotating flange 6 to rotate. The rotating flange 6 drives the pin 56 within the sliding groove, ensuring that the two movements do not interfere with or become stuck, and that the cam variable rod 51 and rotating flange 6 can rotate independently. The connection between the cam variable rod 51 and rotating flange 6 ensures that the cam variable rod 51 can only move within the plane of the valve core's motion, while the sliding groove limits the rotation angle of the rotating flange 6 and the swing cylinder.

[0041] To further optimize the solution, the reversing valve 4 is a three-position four-way reversing valve, which includes a first conducting position, an intermediate position and a second conducting position: when the three-position four-way reversing valve is in the first conducting position, the first variable cylinder 2 is connected to the oil inlet end, and the second variable cylinder 3 is connected to the oil outlet end; when the three-position four-way reversing valve is in the intermediate position, no hydraulic oil flows between the first variable cylinder 2 and the second variable cylinder 3; when the three-position four-way reversing valve is in the second conducting position, the first variable cylinder 2 is connected to the oil outlet end, and the second variable cylinder 3 is connected to the oil inlet end.

[0042] The three-position four-way reversing valve has three working positions. In the first and second conducting positions, the oil inflow and outflow of the first variable cylinder 2 and the second variable cylinder 3 change. When the three-position four-way reversing valve is in the middle position, no hydraulic oil flows in or out of the first variable cylinder 2 and the second variable cylinder 3, the swing cylinder angle of the two-way variable pump 1 is zero degrees, and no hydraulic oil flows out of the two-way variable pump 1, which facilitates precise control of the rotation direction of the two-way variable pump 1 and the flow rate of the two-way variable pump 1. Of course, the reversing valve in the present invention can also adopt a four-position four-way reversing valve, etc.

[0043] A further optimized solution, a cam variable pump control system further includes a low-pressure relief valve 7 and a check valve 8. The inlet of the low-pressure relief valve 7 is connected to the oil inlet and the oil circuit between the reversing valve 4; the oil inlet of the check valve 8 is connected to the oil outlet of the low-pressure relief valve 7, and the oil outlet of the check valve 8 is connected to the oil outlet pipeline of the bidirectional variable pump 1.

[0044] In this embodiment, since the bidirectional variable pump 1 has two output oil circuits, at least two check valves 8 are provided. In this embodiment, two check valves 8 are provided. The oil inlets of both check valves 8 are in communication with the oil outlets of the relief valve 7, and the oil outlets of the two check valves 8 are respectively connected to the two output oil circuits of the bidirectional variable pump 1. The low-pressure relief valve 7 precisely regulates the pressure in the oil circuit between the oil inlet and the reversing valve 4, preventing equipment damage caused by excessive pressure. Excess hydraulic oil is also transferred through the check valve 8 to the main oil circuit, where it is mixed with the hydraulic oil supplied by the bidirectional variable pump 1 and supplied to the hydraulic actuator.

[0045] In this embodiment, the hydraulic actuator is a bidirectional variable motor 9, and power is output through the bidirectional variable motor 9; of course, the hydraulic actuator can also be a bidirectional variable pump or other structure.

[0046] In this embodiment, the first variable cylinder 2 and the second variable cylinder 3 have the same structure and both include a hydraulic cylinder body, an oil storage chamber is provided inside the hydraulic cylinder body, the oil storage chamber is provided with an oil port, and is connected to the internal oil circuit of the reversing valve through the oil port; a variable piston is slidingly provided inside the hydraulic cylinder body, the variable piston of the first variable cylinder 2 is the first variable piston 21, and the variable piston of the second variable cylinder 3 is the second variable piston 31, the first variable piston 21 and the second variable piston 31 are respectively rotatably connected to the rotating flange 6, and are arranged on both sides of the rotation point of the swing cylinder and the rotating flange 6.

[0047] like Figure 1 The working process of a cam variable pump control system shown in FIG. 1 is as follows:

[0048] When the bidirectional variable pump 1 is working, the hydraulic oil enters from the oil inlet end (P port), the initial position of the reversing valve 4 is the middle position, the swing angle of the swing cylinder in the bidirectional variable pump 1 is zero degrees, and there is no flow output.

[0049] The output shaft of the motor 54 rotates clockwise, the camshaft 52 rotates clockwise, and the cam variable rod 51 is controlled to swing counterclockwise. The cam variable rod 51 drives the valve core of the reversing valve 4 to move right, and the reversing valve 4 is switched to the first conduction position (left position). The first variable cylinder 2 takes in oil, and the second variable cylinder 3 presses oil. The first variable piston 21 extends, the second variable piston 31 shortens, and the rotating flange 6 and the swing cylinder swing counterclockwise. At the same time, the hydraulic oil entering the oil inlet end (P port) passes through the low-pressure relief valve 7, and then enters the main oil circuit of the hydraulic pump body after being selected by two one-way valves 8. After being mixed with the hydraulic oil at the oil outlet of the bidirectional variable pump 1, it is supplied to hydraulic actuators such as the bidirectional variable motor 9.

[0050] The output shaft of the motor 54 rotates counterclockwise, the camshaft 52 rotates counterclockwise, and the cam variable rod 51 is controlled to swing clockwise. The cam variable rod 51 drives the valve core of the reversing valve 4 to move to the left, and the reversing valve 4 is switched to the second conduction position (right position). The first variable cylinder 2 presses oil, and the second variable cylinder 3 takes in oil. The first variable piston 21 shortens, and the second variable piston 31 extends. The rotating flange 6 and the swing cylinder swing clockwise. At the same time, the hydraulic oil entering the oil inlet end (P port) passes through the low-pressure relief valve 7, and then enters the main oil circuit of the hydraulic pump body after being selected by two one-way valves 8. After being mixed with the hydraulic oil at the oil outlet of the bidirectional variable pump 1, it is supplied to hydraulic actuators such as the bidirectional variable motor 9.

[0051] The description of the above embodiments is only used to help understand the method of this application and its core idea; at the same time, for those skilled in the art, according to the idea of ​​this application, there will be changes in the specific implementation method and application scope. In summary, the content of this specification should not be understood as limiting the present application.

[0052] It should be understood that the term "and / or" as used herein is merely a description of the relationship between associated objects, indicating that three possible relationships exist. For example, "A and / or B" can represent: A exists alone, A and B exist simultaneously, or B exists alone. Furthermore, the character " / " in this document generally indicates that the associated objects are in an "or" relationship.

[0053] In the description of the present invention, it should be understood that the terms "longitudinal", "transverse", "up", "down", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inside", "outside", etc., indicating the orientation or position relationship, are based on the orientation or position relationship shown in the accompanying drawings, and are only for the convenience of describing the present invention, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as a limitation on the present invention.

[0054] The embodiments described above are merely descriptions of preferred embodiments of the present invention and are not intended to limit the scope of the present invention. Without departing from the spirit of the present invention, various modifications and improvements made to the technical solutions of the present invention by persons skilled in the art should fall within the scope of protection defined by the claims of the present invention.

Claims

1. A cam variable pump control system, characterized in that: include: A bidirectional variable pump (1), the bidirectional variable pump (1) comprising a rotatably arranged swing cylinder, the swing cylinder being used to control the bidirectional variable pump (1) to supply hydraulic oil to a hydraulic actuator; A variable cylinder assembly, the variable cylinder assembly comprising a first variable cylinder (2) and a second variable cylinder (3), the telescopic end of the first variable cylinder (2) and the telescopic end of the second variable cylinder (3) being rotatably connected to two opposite ends of the swing cylinder and being arranged on both sides of a rotation point of the swing cylinder; A reversing valve (4), the reversing valve (4) being provided with an oil inlet end and an oil outlet end, and the reversing valve (4) being in communication with the first variable cylinder (2) and the second variable cylinder (3); the valve core of the reversing valve (4) having at least a first conducting position and a second conducting position: When the valve core of the reversing valve (4) is in the first conducting position, the first variable cylinder (2) is connected to the oil inlet end, and the second variable cylinder (3) is connected to the oil outlet end; When the valve core of the reversing valve (4) is in the second conducting position, the first variable cylinder (2) is connected to the oil outlet end, and the second variable cylinder (3) is connected to the oil inlet end; A cam drive mechanism, the cam drive mechanism comprising a cam (53) and a cam drive element, the cam drive element driving the cam (53) to rotate, and based on the rotation of the cam (53), the valve core of the reversing valve (4) is switched between the first conduction position and the second conduction position; The cam drive mechanism further comprises a cam variable rod (51), the cam variable rod (51) being rotatably connected to the valve core of the reversing valve (4); based on the rotation of the cam (53), the cam variable rod (51) swings within a preset plane, so that the valve core of the reversing valve (4) switches between the first conducting position and the second conducting position; The cam driving element comprises a cam shaft (52), the cam shaft (52) is detachably connected to the cam (53), the cam (53) is spirally extended along its own axis in the outer circumference to form a guide groove, the cam (53) and the cam variable rod (51) are rotatably connected in the guide groove, and the cam shaft (52) is driven by a motor (54); The cam variable pump control system further comprises a rotating flange (6), wherein the rotating flange (6) is detachably connected to the swing cylinder, the telescopic end of the first variable cylinder (2) and the telescopic end of the second variable cylinder (3) are both rotatably connected to the rotating flange (6), and the telescopic end of the first variable cylinder (2) and the telescopic end of the second variable cylinder (3) are respectively arranged on both sides of the rotation point of the swing cylinder and the rotating flange (6).

2. The cam variable pump control system according to claim 1, characterized in that: A sliding groove is provided at one end of the cam variable rod (51) away from the cam driving element, and the rotating flange (6) is rotatably connected to a pin shaft (56), and the pin shaft (56) is movably arranged in the sliding groove.

3. The cam variable pump control system according to claim 1, characterized in that: The reversing valve (4) is a three-position four-way reversing valve, and the three-position four-way reversing valve comprises a first conducting position, an intermediate position, and a second conducting position: When the three-position four-way reversing valve is in the first conducting position, the first variable cylinder (2) is connected to the oil inlet end, and the second variable cylinder (3) is connected to the oil outlet end; When the three-position four-way reversing valve is in the middle position, no hydraulic oil flows between the first variable cylinder (2) and the second variable cylinder (3); When the three-position four-way reversing valve is in the second conducting position, the first variable cylinder (2) is connected to the oil outlet end, and the second variable cylinder (3) is connected to the oil inlet end.

4. The cam variable pump control system according to claim 1, characterized in that: Also includes: a low-pressure relief valve (7), wherein the inlet of the low-pressure relief valve (7) is in communication with the oil circuit between the oil inlet end and the reversing valve (4); A one-way valve (8), wherein the oil inlet end of the one-way valve (8) is in communication with the oil outlet end of the low-pressure relief valve (7), and the oil outlet end of the one-way valve (8) is in communication with the oil outlet pipeline of the bidirectional variable pump (1).

5. The cam variable pump control system according to claim 1, characterized in that: The hydraulic actuator is a bidirectional variable motor (9).

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