阅读说明：本技术 液压控制驱动系统 (Hydraulic control driving system ) 是由 汤波 方敏 叶建 刘琥铖 刘杰 于 2021-07-01 设计创作，主要内容包括：本公开提供了一种液压控制驱动系统,属于机械液压控制领域。所述液压控制驱动系统包括动力输入单元、第一控制单元、第二控制单元和执行元件；所述动力输入单元包括电动机、主泵、控制泵、油箱,所述电动机用于驱动所述主泵和所述控制泵,所述主泵的进油口与所述油箱连通,所述控制泵的进油口与所述油箱连通；所述第一控制单元包括第一伺服阀,所述第一伺服阀的进油口与所述主泵的出油口连通,所述第一伺服阀的回油口与所述油箱连通,所述第一伺服阀的第一油口与所述执行元件的进油口连通,所述第一伺服阀的第二油口与所述执行元件的出油口连通。本公开通过液压控制驱动系统,可以同时满足高精度位置控制及高精度、大区间速度控制要求。(The disclosure provides a hydraulic control driving system, and belongs to the field of mechanical hydraulic control. The hydraulic control driving system comprises a power input unit, a first control unit, a second control unit and an execution element; the power input unit comprises a motor, a main pump, a control pump and an oil tank, wherein the motor is used for driving the main pump and the control pump, an oil inlet of the main pump is communicated with the oil tank, and an oil inlet of the control pump is communicated with the oil tank; the first control unit comprises a first servo valve, an oil inlet of the first servo valve is communicated with an oil outlet of the main pump, an oil return port of the first servo valve is communicated with the oil tank, a first oil port of the first servo valve is communicated with an oil inlet of the execution element, and a second oil port of the first servo valve is communicated with an oil outlet of the execution element. The hydraulic control driving system can meet the requirements of high-precision position control and high-precision and large-interval speed control at the same time.)

1. A hydraulic control drive system, characterized in that it comprises a power input unit (1), a first control unit (2), a second control unit (3) and an actuator (4);

the first control unit (2) comprises a first servo valve (21), an oil inlet (P) of the first servo valve (21) is communicated with an oil outlet of the power input unit (1), an oil return port (T) of the first servo valve (21) is communicated with an oil return port of the power input unit (1), a first oil port (A) of the first servo valve (21) is communicated with a first oil port of the execution element (4), and a second oil port (B) of the first servo valve (21) is communicated with a second oil port of the execution element (4);

the second control unit (3) comprises a servo valve group (31), the servo valve group (31) comprises a main valve (311) and a second servo valve (312), an oil inlet (P) of the main valve (311) is communicated with an oil outlet of the power input unit (1), an oil return port (T) of the main valve (311) is communicated with an oil return port of the power input unit (1), a first oil port (A) of the main valve (311) is communicated with a first oil port of the execution element (4), a second oil port (B) of the main valve (311) is communicated with a second oil port of the execution element (4), an oil inlet (P) of the second servo valve (312) is communicated with an oil outlet of the power input unit (1), an oil return port (T) of the second servo valve (312) is communicated with an oil return port of the power input unit (1), and a first oil port (A) of the second servo valve (312) is communicated with a control oil port (c) of the main valve (311), and a second oil port (B) of the second servo valve (312) is communicated with an oil drainage port (d) of the main valve (311).

2. The hydraulic control drive system according to claim 1, characterized in that the first control unit (2) further comprises a first cut-off valve (22), a second cut-off valve (23), and a first direction change valve (24);

an oil inlet (a) of the first stop valve (22) is communicated with a first oil port (A) of the first servo valve (21), an oil outlet (b) of the first stop valve (22) is communicated with a first oil port of the actuating element (4), an oil drainage port (c) of the first stop valve (22) is communicated with an oil drainage port of the power input unit (1), and a control oil port (d) of the first stop valve (22) is communicated with a working oil port (A) of the first reversing valve (24);

an oil inlet (a) of the second stop valve (23) is communicated with a second oil port (B) of the first servo valve (21), an oil outlet (B) of the second stop valve (23) is communicated with a second oil port of the actuating element (4), an oil drainage port (c) of the second stop valve (23) is communicated with an oil drainage port of the power input unit (1), and a control oil port (d) of the second stop valve (23) is communicated with a working oil port (A) of the first reversing valve (24);

an oil inlet (a) of the first reversing valve (24) is communicated with an oil outlet of the power input unit (1), and an oil return port (b) of the first reversing valve (24) is communicated with an oil return port of the power input unit (1).

3. The hydraulic control drive system according to claim 2, characterized in that the second control unit (3) further comprises a third cut-off valve (32), a fourth cut-off valve (33), and a second direction change valve (34);

an oil inlet (a) of the third stop valve (32) is communicated with a first oil port (A) of the main valve (311), an oil outlet (b) of the third stop valve (32) is communicated with a first oil port of the actuating element (4), an oil drainage port (c) of the third stop valve (32) is communicated with an oil drainage port of the power input unit (1), and a control oil port (d) of the third stop valve (32) is communicated with a working oil port (A) of the second reversing valve (34);

an oil inlet (a) of the fourth stop valve (33) is communicated with a second oil port (B) of the main valve (311), an oil outlet (B) of the fourth stop valve (33) is respectively communicated with a second oil port of the actuating element (4), an oil drainage port (c) of the fourth stop valve (33) is communicated with an oil drainage port of the power input unit (1), and a control oil port (d) of the fourth stop valve (33) is communicated with a working oil port (A) of the second reversing valve (34);

an oil inlet (a) of the second reversing valve (34) is communicated with an oil outlet of the power input unit (1), and an oil return port (b) of the second reversing valve (34) is communicated with an oil return port of the power input unit (1).

4. A hydraulically controlled drive system according to claim 3, characterized in that the first control unit (2) further comprises a first pilot-controlled non-return valve (25), a second pilot-controlled non-return valve (26), a third directional control valve (27);

an oil inlet (a) of the first hydraulic control one-way valve (25) is respectively communicated with an oil outlet (b) of the first stop valve (22) and an oil outlet (b) of the third stop valve (32), an oil outlet (b) of the first hydraulic control one-way valve (25) is communicated with a first oil port of the executing element (4), and an oil drainage port (c) of the first hydraulic control one-way valve (25) is communicated with an oil drainage port of the power input unit (1);

an oil inlet (a) of the second hydraulic control one-way valve (26) is respectively communicated with an oil outlet (b) of the second stop valve (23) and an oil outlet (b) of the fourth stop valve (33), an oil outlet (b) of the second hydraulic control one-way valve (26) is communicated with a second oil port of the actuating element (4), and an oil drainage port (c) of the second hydraulic control one-way valve (26) is communicated with an oil drainage port of the power input unit (1);

an oil inlet (a) of the third reversing valve (27) is communicated with an oil outlet of the power input unit (1), an oil return port (b) of the third reversing valve (27) is communicated with an oil drainage port of the power input unit (1), and a working oil port (A) of the third reversing valve (27) is communicated with a control oil port (d) of the first hydraulic control one-way valve (25) and a control oil port (d) of the second hydraulic control one-way valve (26) respectively.

5. The hydraulic control drive system according to claim 3, characterized in that the second control unit (3) further comprises a speed regulating valve (35), an oil inlet (a) of the speed regulating valve (35) and an oil drain (c) of the third cut-off valve (32) are communicated with an oil drain (c) of the fourth cut-off valve (33), and an oil outlet (b) of the speed regulating valve (35) is communicated with an oil drain of the power input unit (1).

6. The hydraulic control drive system according to claim 5, characterized in that the second control unit (3) further comprises a first damping hole (36), an oil inlet (a) of the first damping hole (36) is communicated with an oil outlet (b) of the speed regulating valve (35), and an oil outlet (b) of the first damping hole (36) is communicated with an oil drain port of the power input unit (1).

7. The hydraulic control drive system according to any one of claims 1-6, characterized by further comprising an implement first relief valve (51) and an implement second relief valve (52);

an oil inlet (a) of the execution first overflow valve (51) is communicated with a first oil port of the execution element (4), a control oil port (b) of the execution first overflow valve (51) is communicated with an oil inlet (a) of the execution first overflow valve (51), and an oil outlet (c) of the execution first overflow valve (51) is communicated with an oil return port of the power input unit (1);

an oil inlet (a) of the second execution overflow valve (52) is communicated with a second oil port of the execution element (4), a control oil port (b) of the second execution overflow valve (52) is communicated with the oil inlet (a) of the second execution overflow valve (52), and an oil outlet (c) of the second execution overflow valve (52) is communicated with an oil return port of the power input unit (1).

8. The hydraulic control drive system according to any one of claims 1-6, wherein the power input unit (1) includes an electric motor (11), a main pump (12), a control pump (13), and an oil tank (14), the electric motor (11) is configured to drive the main pump (12) and the control pump (13), an oil inlet of the main pump (12) is communicated with the oil tank (14), and an oil inlet of the control pump (13) is communicated with the oil tank (14).

9. The hydraulic control drive system according to claim 8, characterized in that the power input unit (1) further comprises a control pump overflow valve (15), an oil inlet (a) of the control pump overflow valve (15) is communicated with an oil outlet of the control pump (13), a control oil outlet (b) of the control pump overflow valve (15) is communicated with an oil inlet (a) of the control pump overflow valve (15), and an oil outlet (c) of the control pump overflow valve (15) is communicated with the oil tank (14).

10. The hydraulic control drive system according to any one of claims 1-6, further comprising a controller (6), the controller (6) being electrically connected to the first servo valve (21), the second servo valve (312) and the actuator (4).

Technical Field

The disclosure belongs to the field of mechanical hydraulic control, and particularly relates to a hydraulic control driving system.

Background

The hydraulic control driving system is a common power driving device, and functions to convert hydraulic energy into mechanical energy, and finally output linear motion (driving a cylinder to linearly move) or output rotary motion (driving a hydraulic motor to rotate) by inputting the flow rate and pressure of fluid in the system.

In the related art, a servo valve with small flow and high precision is generally adopted in a hydraulic control driving system to control an oil cylinder or a hydraulic motor in combination with other valve members, so that the control precision of the system is high.

However, when the system not only requires high control accuracy, but also requires the movement speed to be reached within a limited time, the flow rate of the servo valve is limited, so that the selected servo valve cannot enable the oil cylinder or the liquid motor to reach the speed requirement within the limited time even according to the maximum flow rate output, and finally the actual requirement cannot be met.

Disclosure of Invention

The embodiment of the disclosure provides a hydraulic control driving system, which can simultaneously meet the requirements of high-precision position control and high-precision and large-interval speed control. The technical scheme is as follows:

the embodiment of the disclosure provides a hydraulic control driving system, which comprises a power input unit, a first control unit, a second control unit and an execution element;

the first control unit comprises a first servo valve, an oil inlet of the first servo valve is communicated with an oil outlet of the power input unit, an oil return port of the first servo valve is communicated with an oil return port of the power input unit, a first oil port of the first servo valve is communicated with a first oil port of the execution element, and a second oil port of the first servo valve is communicated with a second oil port of the execution element;

the second control unit comprises a servo valve group, the servo valve group comprises a main valve and a second servo valve, an oil inlet of the main valve is communicated with an oil outlet of the power input unit, an oil return port of the main valve is communicated with an oil return port of the power input unit, a first oil port of the main valve is communicated with a first oil port of the executing element, a second oil port of the main valve is communicated with a second oil port of the executing element, an oil inlet of the second servo valve is communicated with the oil outlet of the power input unit, an oil return port of the second servo valve is communicated with an oil return port of the power input unit, a first oil port of the second servo valve is communicated with a control oil port of the main valve, and a second oil port of the second servo valve is communicated with an oil drainage port of the main valve.

In yet another implementation of the present disclosure, the first control unit further includes a first stop valve, a second stop valve, and a first direction valve;

an oil inlet of the first stop valve is communicated with a first oil port of the first servo valve, an oil outlet of the first stop valve is communicated with a first oil port of the actuating element, an oil drainage port of the first stop valve is communicated with an oil drainage port of the power input unit, and a control oil port of the first stop valve is communicated with a working oil port of the first reversing valve;

an oil inlet of the second stop valve is communicated with a second oil port of the first servo valve, an oil outlet of the second stop valve is communicated with a second oil port of the actuating element, an oil drainage port of the second stop valve is communicated with an oil drainage port of the power input unit, and a control oil port of the second stop valve is communicated with a working oil port of the first reversing valve;

the oil inlet of the first reversing valve is communicated with the oil outlet of the power input unit, and the oil return port of the first reversing valve is communicated with the oil return port of the power input unit.

In yet another implementation of the present disclosure, the second control unit further includes a third stop valve, a fourth stop valve, and a second direction valve;

an oil inlet of the third stop valve is communicated with the first oil port of the main valve, an oil outlet of the third stop valve is communicated with the first oil port of the actuating element, an oil drainage port of the third stop valve is communicated with an oil drainage port of the power input unit, and a control oil port of the third stop valve is communicated with a working oil port of the second reversing valve;

an oil inlet of the fourth stop valve is communicated with a second oil port of the main valve, an oil outlet of the fourth stop valve is respectively communicated with a second oil port of the actuating element, an oil drainage port of the fourth stop valve is communicated with an oil drainage port of the power input unit, and a control oil port of the fourth stop valve is communicated with a working oil port of the second reversing valve;

and an oil inlet of the second reversing valve is communicated with an oil outlet of the power input unit, and an oil return port of the second reversing valve is communicated with an oil return port of the power input unit.

In yet another implementation of the present disclosure, the first control unit further includes a first pilot operated check valve, a second pilot operated check valve, a third directional control valve;

an oil inlet of the first hydraulic control one-way valve is respectively communicated with an oil outlet of the first stop valve and an oil outlet of the third stop valve, an oil outlet of the first hydraulic control one-way valve is communicated with a first oil port of the executing element, and an oil drainage port of the first hydraulic control one-way valve is communicated with an oil drainage port of the power input unit;

an oil inlet of the second hydraulic control one-way valve is respectively communicated with an oil outlet of the second stop valve and an oil outlet of the fourth stop valve, an oil outlet of the second hydraulic control one-way valve is communicated with a second oil port of the executing element, and an oil drainage port of the second hydraulic control one-way valve is communicated with an oil drainage port of the power input unit;

an oil inlet of the third reversing valve is communicated with an oil outlet of the power input unit, an oil return port of the third reversing valve is communicated with an oil drainage port of the power input unit, and a working oil port of the third reversing valve is respectively communicated with a control oil port of the first hydraulic control one-way valve and a control oil port of the second hydraulic control one-way valve.

In another implementation manner of the present disclosure, the second control unit further includes a speed regulating valve, an oil inlet of the speed regulating valve and an oil drain port of the third stop valve are communicated with an oil drain port of the fourth stop valve, and an oil outlet of the speed regulating valve is communicated with an oil drain port of the power input unit.

In another implementation manner of the present disclosure, the second control unit further includes a first damping hole, an oil inlet of the first damping hole is communicated with an oil outlet of the speed regulating valve, and an oil outlet of the first damping hole is communicated with an oil drain port of the power input unit.

In yet another implementation of the present disclosure, the hydraulic control drive system further includes an implement first relief valve and an implement second relief valve;

an oil inlet of the execution first overflow valve is communicated with a first oil port of the execution element, a control oil port of the execution first overflow valve is communicated with an oil inlet of the execution first overflow valve, and an oil outlet of the execution first overflow valve is communicated with an oil return port of the power input unit;

the oil inlet of the execution second overflow valve is communicated with the second oil port of the execution element, the control oil port of the execution second overflow valve is communicated with the oil inlet of the execution second overflow valve, and the oil outlet of the execution second overflow valve is communicated with the oil return port of the power input unit.

In still another implementation manner of the present disclosure, the power input unit includes an electric motor, a main pump, a control pump, and an oil tank, the electric motor is configured to drive the main pump and the control pump, an oil inlet of the main pump is communicated with the oil tank, and an oil inlet of the control pump is communicated with the oil tank.

In another implementation manner of the present disclosure, the power input unit further includes a control pump overflow valve, an oil inlet of the control pump overflow valve is communicated with an oil outlet of the control pump, a control oil inlet of the control pump overflow valve is communicated with an oil inlet of the control pump overflow valve, and an oil outlet of the control pump overflow valve is communicated with the oil tank.

In yet another implementation of the present disclosure, the hydraulic control drive system further includes a controller electrically connected to the first servo valve, the second servo valve, and the actuator.

The technical scheme provided by the embodiment of the disclosure has the following beneficial effects:

when the hydraulic control driving system provided by the embodiment of the disclosure is used, the servo valve group comprises a main valve and a second servo valve, and the valve core action of the main valve is controlled according to the second servo valve, so that the valve core can be positioned at the right position by controlling the second servo valve in the second control unit, at this time, an oil inlet of the second servo valve is communicated with the first working oil port, and an oil return port of the second servo valve is communicated with the second working oil port, so that the second servo valve can push the valve core of the main valve to be at the left position, the oil inlet of the main valve is communicated with the first working oil port, and the oil return port of the main valve is communicated with the second working oil port, thereby driving the execution element to rotate in an accelerated manner according to the first direction.

When the movement speed of the execution element is close to the maximum speed, the control signal of the second servo valve can be kept unchanged, and the first servo valve is controlled simultaneously, so that the valve core of the first servo valve is positioned at the right position, the oil inlet of the first servo valve is communicated with the first working oil port, and the oil return port of the second servo valve is communicated with the second working oil port, so that the execution element can be further driven to continue to move in an accelerated manner according to the first direction by controlling the size of the control signal of the first servo valve, the speed requirement is finally met, and the precision requirement is met. That is, the second servo valve increases the moving speed of the actuator rapidly, and the first servo valve increases the moving speed of the actuator to the required precision.

When the uniform deceleration of the executing element is required, firstly only the second servo valve controls the executing element to decelerate and rotate, and when the executing element decelerates and approaches to a target, the second servo valve is controlled to stop working, and only the first servo valve controls the executing element to continue decelerating to a specified position.

The embodiment of the disclosure enables the actuator to meet the requirements of precision and speed during acceleration and deceleration by simultaneously controlling the operation of the actuator through the first servo valve and the second servo valve.

Drawings

In order to more clearly illustrate the technical solutions in the embodiments of the present disclosure, the drawings needed to be used in the description of the embodiments are briefly introduced below, and it is obvious that the drawings in the following description are only some embodiments of the present disclosure, and it is obvious for those skilled in the art to obtain other drawings based on the drawings without creative efforts.

Fig. 1 is a schematic diagram of a hydraulically controlled drive system provided by an embodiment of the present disclosure.

The symbols in the drawings represent the following meanings:

1. a power input unit; 11. an electric motor; 12. a main pump; 13. controlling the pump; 14. an oil tank; 15. controlling a pump relief valve;

2. a first control unit; 21. a first servo valve; 22. a first shut-off valve; 23. a second stop valve; 24. a first direction changing valve; 25. a first hydraulic control check valve; 26. a second hydraulic control one-way valve; 27. a third directional control valve;

3. a second control unit; 31. a servo valve group; 311. a main valve; 312. a second servo valve; 32. a third stop valve; 33. a fourth stop valve; 34. a second directional control valve; 35. a speed regulating valve; 36. a first orifice;

4. an actuator;

51. executing a first overflow valve; 52. executing a second overflow valve; 6. and a controller.

Detailed Description

To make the objects, technical solutions and advantages of the present disclosure more apparent, embodiments of the present disclosure will be described in detail with reference to the accompanying drawings.

The disclosed embodiment provides a hydraulic control drive system, which comprises a power input unit 1, a first control unit 2, a second control unit 3 and an actuator 4, as shown in fig. 1. The first control unit 2 comprises a first servo valve 21, an oil inlet P of the first servo valve 21 is communicated with an oil outlet of the power input unit 1, an oil return port T of the first servo valve 21 is communicated with an oil return port of the power input unit 1, a first oil port a of the first servo valve 21 is communicated with a first oil port P1 of the actuating element 4, and a second oil port B of the first servo valve 21 is communicated with a second oil port P2 of the actuating element 4.

The second control unit 3 includes a servo valve group 31, the servo valve group 31 includes a main valve 311 and a second servo valve 312, an oil inlet P of the main valve 311 is communicated with an oil outlet of the power input unit 1, an oil return port T of the main valve 311 is communicated with an oil return port of the power input unit 1, a first port a of the main valve 311 is communicated with a first port P1 of the actuating element 4, a second port B of the main valve 311 is communicated with a second port P2 of the actuating element 4, an oil inlet P of the second servo valve 312 is communicated with the oil outlet of the power input unit 1, the oil return port T of the second servo valve 312 is communicated with an oil return port of the power input unit 1, the first port a of the second servo valve 312 is communicated with a control port c of the main valve 311, and a second port B of the second servo valve 312 is communicated with an oil drain port d of the main valve 311.

When the hydraulic control driving system provided by the embodiment of the present disclosure is used, since the servo valve group 31 includes the main valve 311 and the second servo valve 312, and the spool action of the main valve 311 is controlled according to the second servo valve 312, the spool of the second servo valve 312 can be located at the rightmost position by controlling the second servo valve 312, at this time, the oil inlet P of the second servo valve 312 is communicated with the first working port a, and the oil return port T of the second servo valve 312 is communicated with the second working port B, so that the second servo valve 312 can push the spool of the main valve 311 at the left position, the oil inlet P of the main valve 311 is communicated with the first working port a, and the oil return port T of the main valve 311 is communicated with the second working port B, thereby driving the actuator 4 to rotate in an accelerated manner according to the first direction.

When the movement speed of the actuator 4 is close to the maximum speed, the control signal of the second servo valve 312 may be kept unchanged, and the first servo valve 21 is controlled simultaneously, so that the valve core of the first servo valve 21 is located at the rightmost position, the oil inlet P of the first servo valve 21 is communicated with the first working oil port a, and the oil return port T of the first servo valve 21 is communicated with the second working oil port B, so that the actuator 4 may be further driven to continue to accelerate in the first direction by changing the magnitude of the control signal of the first servo valve 21, and finally reach the target speed, and simultaneously reach the precision requirement. That is, the moving speed of the actuator 4 is first rapidly increased by the second servo valve 312, and then the moving speed of the actuator 4 reaches a target value by the first servo valve 21 in cooperation with the second servo valve 312, satisfying the accuracy.

When the uniform deceleration of the actuator 4 is required, firstly only the second servo valve 312 controls the actuator 4 to decelerate, and when the actuator 4 decelerates and approaches a target, the second servo valve 312 is controlled to stop working, and only the first servo valve 21 controls the actuator 4 to continue decelerating to a specified position.

The disclosed embodiment enables the actuator 4 to meet accuracy and speed requirements both during acceleration and deceleration by controlling the operation of the actuator 4 simultaneously by means of the first and second servo valves 21, 312.

In this embodiment, the hydraulic control driving system further includes a controller 6, and the controller 6 is electrically connected to the first servo valve 21 and the second servo valve 312 respectively to automatically control the operating states of the first servo valve 21 and the second servo valve 312.

The controller 6 may enable the first servo valve 21 and the second servo valve 312 to respectively receive different control signals, for example, current signals with different magnitudes and directions.

In this embodiment, the flow rate of the first servo valve 21 is small and is directly controlled by an electric signal. When the control current input to the first servo valve 21 in the controller 6 is 0 to 10V, the valve element of the first servo valve 21 is in the right position, the oil inlet P of the first servo valve 21 is communicated with the first working oil port a, the oil return port T of the first servo valve 21 is communicated with the second working oil port B, the internal oil path of the first servo valve 21 is P → A, B → T, and correspondingly, the motor rotates forward.

When the control current is 0 to-10V, the valve core of the first servo valve 21 is at the left position, the oil inlet P of the first servo valve 21 is communicated with the second working oil port B, the oil return port T of the first servo valve 21 is communicated with the first working oil port A, the internal oil path is P → B, A → T, and correspondingly, the motor rotates reversely.

Illustratively, to ensure control accuracy, the first servo valve 21 is closed loop with spool position feedback.

In this embodiment, the flow rate of the servo valve group 31 is large, and the servo valve group is driven by electro-hydraulic. The controller 6 directly controls the second servo valve 312, and inputs different electric signals to the second servo valve 312. The second servo valve 312 outputs hydraulic oil to control the movement of the main valve 311.

When the control current input to the second servo valve 312 by the controller 6 is 0 to 10V, the spool of the second servo valve 312 is in the left position, the spool of the main valve 311 is pushed to be in the right position, the oil inlet P of the main valve 311 is communicated with the first working port a, the oil return port T of the main valve 311 is communicated with the second working port B, the internal oil path of the main valve 311 is P → A, B → T, and correspondingly, the motor rotates forward.

When the control current input to the second servo valve 312 by the controller 6 is 0 to-10V, the spool of the second servo valve 312 is at the right position, the spool of the main valve 311 is pushed to the left position, the oil inlet P of the main valve 311 is communicated with the second working port B, the oil return port T of the main valve 311 is communicated with the first working port a, the internal oil path of the main valve 311 is P → B, A → T, and correspondingly, the hydraulic motor rotates reversely.

In order to ensure the control precision, the second servo valve 312 and the main valve 311 are closed loops by valve core position feedback.

For example, the first servo valve 21 and the servo valve group 31 have the same nominal pressure and different flow rates. The first servo valve 21 has a small flow, the maximum control flow is 10% of the flow corresponding to the maximum speed of the motor, correspondingly, the motor speed control range is 0.5% -10%, the ratio of the minimum speed to the maximum speed is 20%, and the control accuracy requirement is far lower than the theoretical value generally given in the sample of the first servo valve by 0.5% -1%. The flow rate of the servo valve group 31 is large, the maximum control flow rate is 90% of the flow rate corresponding to the maximum speed of the motor, the sum of the flow rates of the first servo valve 21 and the second servo valve 312 corresponds to the speed control range of the hydraulic motor, the ratio of the minimum speed to the maximum speed is 10%, and the control precision requirement is far lower than the theoretical value generally given in a servo valve sample by 0.5% -1%.

In this embodiment, the actuator 4 is a motor, and the motor includes an encoder electrically connected to the controller 6.

The encoder is used for detecting the rotation speed and position of the motor and transmitting signals to the controller 6, and the controller 6 controls the first servo valve 21 and the second servo valve 312 in turn through the detected signals.

When the motor is accelerated and the encoder detects that the rotating speed of the motor reaches the target value, the information can be fed back to the controller 6, the controller can automatically control the control signal of the second servo valve 312 to be unchanged, then the control signal is input to the first servo valve 21, and only the first servo valve 21 controls the motor to continuously accelerate. If the motor needs to be decelerated and the encoder detects that the rotational speed of the motor is rapidly reduced to the target value, this information may be fed back to the controller 6, the controller does not input a control signal to the second servo valve 312 and inputs a control signal to the first servo valve 21, and only the first servo valve 21 controls the motor to continue accelerating. If the motor needs to keep rotating at a constant speed, the controller automatically controls the control signal of the first servo valve 21 or the second servo valve 312 to be kept unchanged according to the detection information of the encoder.

Alternatively, the power input unit 1 includes an electric motor 11, a main pump 12, a control pump 13, and an oil tank 14, wherein the electric motor 11 is used for driving the main pump 12 and the control pump 13, an oil inlet of the main pump 12 is communicated with the oil tank 14, and an oil inlet of the control pump 13 is communicated with the oil tank 14.

The electric motor 11 is used for driving the main pump 12 or the control pump 13 to rotate, and the oil tank 14 is used for supplying power oil to the whole hydraulic control driving system. The main pump 12 is used for pumping power oil for a main oil gallery of the hydraulic control drive system, and the control pump 13 is used for pumping power oil for a control oil gallery of the hydraulic control drive system.

Optionally, the power input unit 1 further includes a control pump overflow valve 15, an oil inlet a of the control pump overflow valve 15 is communicated with an oil outlet of the control pump 13, a control oil port b of the control pump overflow valve 15 is communicated with an oil inlet a of the control pump overflow valve 15, and an oil outlet c of the control pump overflow valve 15 is communicated with the oil tank 14 through an oil return line. The oil return pipeline is provided with elements such as a filter, a cooler and the like.

Control pump spill valve 15 enables the output pressure (i.e., outlet pressure) of control pump 13 to be kept stable.

Optionally, the first control unit 2 further comprises a first shut-off valve 22, a second shut-off valve 23 and a first direction valve 24. The oil inlet a of the first stop valve 22 is communicated with the first oil port a of the first servo valve 21, the oil outlet b of the first stop valve 22 is communicated with the first oil port P1 of the actuating element 4, the oil discharge port c of the first stop valve 22 is communicated with the oil tank 14, the control oil port d of the first stop valve 22 is communicated with the working oil port a of the first reversing valve 24, and the oil discharge port c of the first stop valve 22 is communicated with the control oil port d of the first stop valve 22 through the second damping hole. An oil inlet a of the second stop valve 23 is communicated with the second oil port B of the first servo valve 21, an oil outlet B of the second stop valve 23 is respectively communicated with the second oil port P2 of the actuating element 4, an oil drainage port c of the second stop valve 23 is communicated with the oil tank 14, and a control oil port d of the second stop valve 23 is communicated with the working oil port a of the first reversing valve 24. The oil release port c of the second cut-off valve 23 is communicated with the control port d of the second cut-off valve 23 through a second orifice. An oil inlet a of the first reversing valve 24 is communicated with an oil outlet of the control pump 13, and an oil return port b of the first reversing valve 24 is communicated with the oil tank 14.

The first direction valve 24 is used to control the on/off of the first and second stop valves 22 and 23. When the first reversing valve 24 is powered off, oil leakage at two sides of the first stop valve 22 and the second stop valve 23 is closed under the action of spring force, so that oil paths between the working oil port a and the working oil port B of the first servo valve 21 and the first oil port P1 and the second oil port of the actuating element 4 are disconnected, and the first servo valve 21 does not participate in work.

When the first reversing valve 24 is powered on, the control oil is connected to the right side of the first stop valve 22 and the right side of the second stop valve 23 to push the valve core to reverse, so that the working oil port a and the working oil port B of the first servo valve 21 are communicated with the oil passages between the first oil port P1 and the second oil port of the actuating element 4, and the first servo valve 21 participates in working.

That is, the first cut valve 22 and the second cut valve 23 are used to control whether the first servo valve 21 is engaged. The first stop valve 22 and the second stop valve 23 are controlled by a first reversing valve 24, and synchronous on-off is guaranteed.

In this embodiment, the drain port c of the first stop valve 22 is communicated with the drain port of the oil tank 14 through a drain line, and the drain port c of the second stop valve 23 is communicated with the drain port of the oil tank 14 through a drain line, wherein the drain line is not connected with any element. The oil return port b of the first reversing valve 24 is communicated with an oil return port of the oil tank 14 through an oil return pipeline, and the oil return pipeline is provided with elements such as a filter, a cooler and the like.

Optionally, the second control unit 3 further comprises a third shut-off valve 32, a fourth shut-off valve 33 and a second direction valve 34. The oil inlet a of the third cut-off valve 32 is communicated with the first port a of the main valve 311, the oil outlet b of the third cut-off valve 32 is communicated with the first port P1 of the actuator 4, the oil discharge port c of the third cut-off valve 32 is communicated with the oil tank 14, and the control port d of the third cut-off valve 32 is communicated with the working port a of the second directional valve 34. The drain port c of the third cut-off valve 32 communicates with the control port d of the third cut-off valve 32 through the second orifice. An oil inlet a of the fourth cut-off valve 33 is communicated with the second port B of the main valve 311, oil outlets of the fourth cut-off valve 33 are respectively communicated with the second port P2 of the actuating element 4, an oil drainage port c of the fourth cut-off valve 33 is communicated with the oil tank 14, and a control port d of the fourth cut-off valve 33 is communicated with the working port a of the second directional valve 34. The drain port c of the fourth cut-off valve 33 communicates with the control port d of the fourth cut-off valve 33 through a second orifice. An oil inlet a of the second reversing valve 34 is communicated with an oil outlet of the control pump 13, and an oil return port b of the second reversing valve 34 is communicated with the oil tank 14.

The second direction switching valve 34 is used to control the opening and closing of the third and fourth stop valves 32 and 33. When the second directional valve 34 is de-energized, oil is drained from both sides of the third stop valve 32 and the fourth stop valve 33, and the oil is closed under the action of the spring force, so that the oil paths between the first working oil port a and the second working oil port B of the main valve 311 and the first oil port P1 and the second oil port of the actuator 4 are disconnected, and the main valve 311 does not participate in the operation.

When the second directional valve 34 is powered, the right sides of the third stop valve 32 and the fourth stop valve 33 are connected with the control oil to push the valve core to be directional, so that the first working oil port a and the second working oil port B of the main valve 311 are communicated with the oil passages between the first oil port P1 and the second oil port of the actuator 4, and the main valve 311 participates in the operation.

That is, the third and fourth stop valves 32 and 33 are used to control whether or not the main valve 311 is engaged. The third stop valve 32 and the fourth stop valve 33 are controlled by a second reversing valve 34, and synchronous on-off is guaranteed.

In addition, the drain port c of the fourth cut-off valve 33 communicates with the control port d of the fourth cut-off valve 33 through the second orifice, so that the control oil of the fourth cut-off valve 33 leaks a little, and the fourth cut-off valve 33 is soft when opened. Similarly, the first stop valve 22, the second stop valve 23, and the third stop valve 32 are also the same principle.

By the same token, in the present embodiment, the drain port c of the third cut-off valve 32 communicates with the drain port of the oil tank 14 through a drain line, and the drain port c of the fourth cut-off valve 33 communicates with the drain port of the oil tank 14 through a drain line, wherein no component is connected to the drain line. The oil return port b of the second direction valve 34 is communicated with the oil return port of the oil tank 14 through an oil return line, and the oil return line is provided with elements such as a filter, a cooler and the like.

Optionally, the first control unit 2 further includes a first pilot-controlled check valve 25, a second pilot-controlled check valve 26, and a third directional control valve 27, an oil inlet a of the first pilot-controlled check valve 25 is respectively communicated with an oil outlet b of the first cut-off valve 22 and an oil outlet b of the third cut-off valve 32, an oil outlet b of the first pilot-controlled check valve 25 is communicated with the first oil port P1 of the actuator 4, and an oil drainage port c of the first pilot-controlled check valve 25 is communicated with the oil tank 14. An oil inlet a of the second hydraulic control check valve 26 is respectively communicated with an oil outlet b of the second stop valve 23 and an oil outlet b of the fourth stop valve 33, an oil outlet b of the second hydraulic control check valve 26 is communicated with a second oil port P2 of the actuating element 4, and an oil drainage port c of the second hydraulic control check valve 26 is communicated with the oil tank 14. An oil inlet a of the third reversing valve 27 is communicated with an oil outlet of the control pump 13, an oil return port b of the third reversing valve 27 is communicated with the oil tank 14, and a working oil port a of the third reversing valve 27 is respectively communicated with a control oil port d of the first hydraulic control one-way valve 25 and a control oil port d of the second hydraulic control one-way valve 26.

The first pilot-controlled check valve 25 is used for controlling the oil path entering the inside of the actuating element 4 to only flow in a single direction, so that the actuating element 4 is ensured to work normally. The second hydraulic control one-way valve 26 is used for controlling the oil path from the inside of the actuating element 4 to only flow in one direction, so that the actuating element 4 can work normally. The third reversing valve 27 is used for controlling the on-off of the first hydraulic control one-way valve 25 and the second hydraulic control one-way valve 26. When the third reversing valve 27 is de-energized, the first pilot operated check valve 25 and the second pilot operated check valve 26 are closed, and the actuator 4 is locked. When the third directional control valve 27 is energized, the first pilot operated check valve 25 and the second pilot operated check valve 26 are opened, and the actuator 4 is freely movable.

In the same way, in this embodiment, the oil drainage port c of the first pilot-controlled check valve 25, the oil drainage port c of the second pilot-controlled check valve 26, and the oil return port b of the third directional control valve 27 are all communicated with the oil drainage port of the oil tank 14 through a drainage pipeline, wherein no component is connected to the drainage pipeline.

Optionally, the second control unit 3 further includes a speed regulating valve 35, an oil inlet a of the speed regulating valve 35 is respectively communicated with an oil drainage port c of the third stop valve 32 and an oil drainage port c of the fourth stop valve 33, and an oil outlet b of the speed regulating valve 35 is communicated with the oil tank 14.

The speed regulating valve 35 is used for adjusting the reversing time of the third stop valve 32 and the fourth stop valve 33, so that the third stop valve 32 and the fourth stop valve 33 can be smoothly reversed, and the pressure impact on the oil path of the inlet and the outlet of the actuating element 4 when the third stop valve 32 and the fourth stop valve 33 are opened is further reduced. The opening size of the speed regulating valve 35 is adjusted to roughly adjust the reversing time.

By the same token, in this embodiment, the oil drain port c of the speed regulating valve 35 is communicated with the oil drain port of the oil tank 14 through an oil drain line, wherein no element is connected to the oil drain line.

Optionally, the second control unit 3 further includes a first damping hole 36, an oil inlet a of the first damping hole 36 is communicated with an oil outlet b of the speed regulating valve 35, and an oil outlet b of the first damping hole 36 is communicated with the oil tank 14.

The first orifice 36 is used for adjusting the reversing time of the third stop valve 32 and the fourth stop valve 33, so that the third stop valve 32 and the fourth stop valve 33 can be smoothly reversed, and the pressure impact on the oil path of the inlet and the outlet of the actuator 4 when the third stop valve 32 and the fourth stop valve 33 are opened is reduced. The first orifice 36 is replaced to fine tune the commutation time.

The oil outlet b of the first damping hole 36 is communicated with the oil drainage port of the oil tank 14 through a drainage pipeline which is not connected with any element.

Optionally, the hydraulic control drive system further includes an actuating first overflow valve 51 and an actuating second overflow valve 52, an oil inlet a of the actuating first overflow valve 51 is communicated with the first port P1 of the actuating element 4, a control port b of the actuating first overflow valve 51 is communicated with an oil inlet a of the actuating first overflow valve 51, and an oil outlet c of the actuating first overflow valve 51 is communicated with the oil tank 14. The oil inlet a of the second execution overflow valve 52 is communicated with the second oil port P2 of the execution element 4, the control oil port b of the second execution overflow valve 52 is communicated with the oil inlet a of the second execution overflow valve 52, and the oil outlet c of the second execution overflow valve 52 is communicated with the oil tank 14.

The first overflow valve 51 and the second overflow valve 52 are implemented to cooperate together to protect the actuator 4 from over-pressurization of the actuator 4.

An oil outlet c of the first executing overflow valve 51 and an oil outlet c of the second executing overflow valve 52 are both communicated with an oil return port of the oil tank 14 through an oil return pipeline, and the oil return pipeline is provided with elements such as a filter, a cooler and the like.

The working process of the hydraulic control driving system provided by the embodiment of the disclosure is briefly described as follows:

first, the second direction valve 34 and the third direction valve 27 are controlled so that the second direction valve 34 and the third direction valve 27 are both powered, the third stop valve 32 and the fourth stop valve 33 are opened, the first pilot operated check valve 25 and the second pilot operated check valve 26 are opened, and the second servo valve 312 is controlled so that the second servo valve 312 controls the hydraulic motor to rapidly perform uniform acceleration rotation.

When the hydraulic motor detects that the rotating speed of the motor is accelerated to 10% of the maximum speed by an encoder, the electric signal of the second servo valve 312 is kept unchanged, so that the first reversing valve 24 is electrified, the first stop valve 22 and the second stop valve 23 are both opened, and the first servo valve 21 controls the motor to continue to rotate at uniform acceleration and then keep moving at a uniform speed after the motor continues rotating at the maximum speed.

When the motor uniform deceleration is required, the first servo valve 21 keeps the control signal unchanged, only the second servo valve 312 controls the hydraulic motor to decelerate, when the encoder of the motor detects that the rotating speed of the motor decelerates to 10% of the maximum speed, the second reversing valve 34 is controlled, the second reversing valve 34 is de-energized, the third stop valve 32 and the fourth stop valve 33 are closed, and only the first servo valve 21 controls the motor to continue decelerating to the designated position.

That is, when the system requires not only high precision of motor position control but also high precision of speed control and large speed control interval (for example, the speed control range is 0.5% -100% of rated speed), the above first servo valve 21 and the servo valve set 31 are adopted to simultaneously control in parallel, so that the requirements of high precision position control and high precision and large interval speed control can be simultaneously satisfied.

The above description is meant to be illustrative of the principles of the present disclosure and not to be taken in a limiting sense, and any modifications, equivalents, improvements and the like that are within the spirit and scope of the present disclosure are intended to be included therein.