Asymmetric actuator electro-hydraulic control system and method

Abstract

The invention discloses an asymmetric actuator electro-hydraulic control system and method. The asymmetric actuator electro-hydraulic control system comprises an energy supply and storage unit, a hydraulic control unit, a control unit and an asymmetric actuator. The energy supply and storage unit comprises a power battery unit, a high-voltage distributor, a motor controller and a motor generator which are electrically connected in sequence; the hydraulic control unit comprises a main pump motor, a volume compensation pump motor, an electro-hydraulic directional control valve, a holding valve, an oil tank and an energy accumulator, a port A1 of the main pump motor is connected with an oil inlet of the holding valve, an oil outlet of the holding valve is communicated with a port M of a rodless cavity of the asymmetric actuator, and a port B1 of the main pump motor is communicated with a port N of a rod cavity of the asymmetric actuator. The problem of system oscillation caused by the flow difference of the two cavities of the asymmetric actuator is effectively solved. The energy recovery unit can recover potential energy, and the endurance time of equipment is remarkably prolonged. The automatic switching function of the electro-hydraulic reversing valve effectively reduces the response time of the system so as to meet the high-frequency action requirement of engineering machinery.

Description

Technical Field

[0001] The present invention relates to the technical field of hydraulic control systems, and in particular to an asymmetric actuator electro-hydraulic control system and method. Background Art

[0002] Asymmetric actuators, as key actuators in hydraulic systems, face unique challenges in hydraulic system design and control due to the asymmetric flow demand caused by the difference in effective cross-sectional area between the rod and rodless chambers. Traditional solutions suffer from the following technical drawbacks: The imbalance in flow between the two chambers requires additional compensation circuits, increasing system complexity. During switching control, sudden changes in flow can easily lead to pressure shocks and vibration. Furthermore, overflow losses in open systems result in significant energy waste. While the current mainstream pump control solution offers a simple structure and high energy efficiency, it places stringent demands on pump control accuracy. While valve control solutions offer fast response and flexible control, they suffer from significant energy loss and high system complexity. Existing technologies struggle to balance control accuracy and energy efficiency, especially in operating conditions requiring frequent starting, stopping, and braking, where energy recovery is particularly problematic. Furthermore, traditional systems often require complex multi-valve coordination to address the unique operating conditions of asymmetric actuators, resulting in delayed system response and reduced reliability. For vertical and horizontal operating conditions in applications such as construction machinery, existing solutions struggle to achieve the coordinated optimization of smooth control and energy recovery. Summary of the Invention

[0003] In view of this, the present invention provides an asymmetric actuator electro-hydraulic control system, which has the advantages of simplifying the system structure, improving energy utilization efficiency, realizing bidirectional energy recovery and precise flow compensation.

[0004] To achieve the above object, the present invention provides the following technical solutions: An asymmetric actuator electro-hydraulic control system comprises: an energy supply and energy storage unit, a hydraulic control unit, a control unit and an asymmetric actuator.

[0005] Among them, the energy supply and energy storage unit, the hydraulic control unit and the asymmetric actuator are all controlled by the control unit; the energy supply and energy storage unit includes a power battery unit, a high-voltage distributor, a motor controller and an electric generator that are electrically connected in sequence; the hydraulic control unit includes a main pump motor, a volume compensation pump motor, an electro-hydraulic reversing valve, a holding valve, an oil tank and an accumulator. The main pump motor and the volume compensation pump motor are respectively connected to the electric generator through transmission, the A1 port of the main pump motor is connected to the oil inlet of the holding valve, and the oil outlet of the holding valve is connected to the rodless cavity M port of the asymmetric actuator. The control port of the holding valve is connected to the control unit signal, the B1 port of the main pump motor is connected to the rod chamber N port of the asymmetric actuator; the A2 port of the volume compensation pump motor is connected to the oil tank, and the B2 port of the volume compensation pump motor is connected to the accumulator and the oil inlet of the electro-hydraulic reversing valve respectively, the first working oil port of the electro-hydraulic reversing valve is connected to the oil circuit between the A1 port of the main pump motor and the oil inlet of the holding valve through a pipeline, and the second working oil port of the electro-hydraulic reversing valve is connected to the oil circuit between the B1 port of the main pump motor and the rod chamber N port of the asymmetric actuator through a pipeline.

[0006] Preferably, the electric energy stored in the power battery unit is distributed to the motor controller through the high-voltage distributor, and the DC power is converted to AC after being inverted to drive the electric generator to output power. At the same time, the electric energy generated by the electric generator is converted to DC by the motor controller and then recovered to the power battery unit through high-voltage distribution for storage.

[0007] Preferably, the electric generator includes a motor output working state and a motor power generation working state; when the electric generator is in the motor output working state, the electric generator drives the main pump motor and the volume compensation pump motor to be in pump mode; when the main pump motor and the volume compensation pump motor are in motor mode, the main pump motor and the volume compensation pump motor drive the electric generator to work in the motor power generation working state.

[0008] Preferably, the electro-hydraulic reversing valve is a three-position three-way electromagnetic reversing valve, including an upper working position, an initial position and a lower working position, and the control ports on both sides of the electro-hydraulic reversing valve are both connected to the control unit signal; when the electro-hydraulic reversing valve is in the upper working position, the oil inlet of the electro-hydraulic reversing valve is connected to the first working oil port of the electro-hydraulic reversing valve, and at this time, the oil inlet of the electro-hydraulic reversing valve and the oil circuit between the A1 port of the main pump motor and the oil inlet of the holding valve are in a connected state; when the electro-hydraulic reversing valve is in the initial position, the oil inlet of the electro-hydraulic reversing valve and the first working oil port of the electro-hydraulic reversing valve and the second working oil port of the electro-hydraulic reversing valve are all in a cut-off state; when the electro-hydraulic reversing valve is in the lower working position, the oil inlet of the electro-hydraulic reversing valve is connected to the second working oil port of the electro-hydraulic reversing valve, and at this time, the oil inlet of the electro-hydraulic reversing valve and the oil circuit between the B1 port of the main pump motor and the rod chamber N port of the asymmetric actuator are in a connected state.

[0009] Preferably, a first pressure sensor is provided on the oil circuit between the A1 port of the main pump motor and the oil inlet of the holding valve, and a second pressure sensor is provided on the oil circuit between the B1 port of the main pump motor and the rod chamber N port of the asymmetric actuator, and both the first pressure sensor and the second pressure sensor are connected to the control unit signal.

[0010] Preferably, the telescopic rod of the asymmetric actuator is connected to the load, and the telescopic action of the telescopic rod of the asymmetric actuator drives the load to extend and retract. A displacement sensor is provided at the load end, and the displacement sensor is connected to the control unit signal.

[0011] Preferably, the control unit includes a joystick, a button is provided directly above the joystick, the backward angle change of the joystick is linearly proportional to the load rising speed, and the drive motor works at the same time; the forward angle change of the joystick is linearly proportional to the load descending speed, and the drive motor works at the same time; the stroke of pressing the button directly above the joystick is linearly proportional to the control pump swing angle from 0 to the maximum negative swing angle, and the load is driven to fall without power; when the joystick is in a natural state without operation and resets to the middle position and the button reset does not move, the electro-hydraulic reversing valve is in the initial position, and the oil circuit is in a cut-off state at this time; the three operations of the joystick forward, backward and button are independent of each other and there is no compound action, and the priority level is executed according to the first operation, that is, the first operation is not reset and the next operation instruction is not executed.

[0012] The present invention also proposes an asymmetric actuator electro-hydraulic control method, which is applied to the asymmetric actuator electro-hydraulic control system in the above-mentioned embodiment, including: a vertical working condition control method and a horizontal working condition control method. The vertical working condition control method includes the control of the joystick of the operating handle when it is backward, the control of the joystick of the operating handle when it is forward, and the control when the button of the joystick of the operating handle is pressed to reset the state. The horizontal working condition control method includes the control of the joystick of the operating handle when it is forward and the control of the joystick of the operating handle when it is backward.

[0013] Preferably, under vertical working conditions, the control of the joystick of the operating handle when it is moved backward includes: starting the machine, self-checking the equipment status, moving the operating handle backward, and linearly increasing the pump swing angle from 0 to the maximum positive swing angle through the electro-hydraulic proportional control of the control unit. At the same time, after the control unit receives the state signal that the swing angle is greater than 0, it adjusts the motor controller to drive the motor, the electric generator is in the motor output working state, the main pump motor and the volume compensation pump motor are in pump mode, the electro-hydraulic reversing valve automatically switches to the lower working position, and the rodless chamber of the asymmetric actuator is controlled to flow liquid, the load increases, and when the load of the rodless chamber increases, the low-pressure oil discharged from the rod chamber of the asymmetric actuator flows through the pipeline to the B1 port of the main pump motor.

[0014] Preferably, under vertical operation conditions, the control of the joystick when the joystick is moved forward includes: starting the machine, self-checking the equipment status, moving the joystick forward, and linearly increasing the pump swing angle from 0 to the maximum negative swing angle through the control unit electro-hydraulic proportional control. At the same time, after the control unit receives a state signal indicating that the swing angle is less than 0, it regulates the motor controller to drive the motor, the electric generator is in the motor output working state, the main pump motor and the displacement compensation pump motor are in pump mode, the electro-hydraulic reversing valve automatically switches to the upper working position, the main pump motor controls the high-pressure oil to flow from the B1 port of the main pump motor and enter the rod chamber of the N port of the asymmetric actuator, thereby reducing the liquid inlet load of the rod chamber. When the liquid inlet load of the rod chamber decreases, the oil discharged from the rodless chamber of the asymmetric actuator flows through the holding valve to the A1 port of the main pump motor. Due to the different cross-sectional areas of the two chambers of the asymmetric actuator, the B2 port of the displacement compensation pump motor is connected to the oil circuit of the rodless chamber of the asymmetric actuator. The excess oil of the accumulator auxiliary enters through the B2 port of the displacement compensation pump motor and exits through the A2 port of the displacement compensation pump motor and flows back to the oil tank.

[0015] Preferably, under vertical working conditions, the control when the button is pressed in the reset state of the joystick of the operating handle includes: power-on, equipment status self-check, the stroke of pressing the button directly above the handle is linearly symmetrical with the electro-hydraulic proportional control pump swing angle from 0 to the maximum negative swing angle, the load falls without power, the control unit controls the oil circuit inside the valve to remain connected, the electro-hydraulic reversing valve automatically switches to the lower working position, and feeds back the current status to the control unit, through the control unit, the control pump swing angle increases linearly from 0 to the maximum negative swing angle with the stroke of pressing the button, the main pump motor and the volume compensation pump motor are in motor mode, and the control unit receives the swing angle After the state signal is less than 0, the electric generator is in the generator working state; the oil discharged from the rodless chamber of the asymmetric actuator flows to the A1 port of the main pump motor through the holding valve, and the main pump motor outputs mechanical energy to drive the electric generator to generate electricity, thereby reducing the load of the rodless chamber outlet. When the load of the rodless chamber outlet decreases, part of the oil at the B1 port of the main pump motor enters the rod chamber of the asymmetric actuator. Due to the different cross-sectional areas of the two chambers of the asymmetric actuator, the oil circuit from the B2 port of the volume compensation pump motor to the B1 port of the main pump motor is connected, and the excess oil of the accumulator assists enters through the B2 port of the volume compensation pump motor, and exits through the A2 port of the volume compensation pump motor and flows back to the oil tank.

[0016] Preferably, under horizontal working conditions, the control of the joystick of the operating handle when it is moved forward includes: starting the machine, self-checking the equipment status, the pump motor swing angle is in the positive swing angle state, at this time the joystick is reset, the control unit receives the reset signal, adjusts the motor controller, the electric generator is in the power generation working state, the main pump motor and the volume compensation pump motor are in motor mode, the electro-hydraulic reversing valve automatically switches to the upper working position, the control unit controls the oil circuit inside the valve to remain connected, the rod cavity of the asymmetric actuator is squeezed out of the liquid by the load inertia force, the electricity generated by the electric generator is rectified and inverted by the motor controller, and the electric energy is recovered to the power battery unit through high-voltage distribution, and when the load is forward braking and the rod cavity discharges liquid, the oil at the A1 port of the main pump motor all enters the rodless cavity of the asymmetric actuator, and the accumulator auxiliary volume compensation pump motor compensates the oil from the oil tank to the rodless cavity of the asymmetric actuator.

[0017] Preferably, under horizontal working conditions, the control of the joystick of the operating handle when it is moved backward includes: starting the machine, self-checking the equipment status, the pump motor swing angle is in a negative swing angle state, the motor and the pump are in energy output mode, at this time the joystick is reset, the control unit receives a reset signal, adjusts the motor controller, the electric generator is in a power generation working state, the main pump motor and the volume compensation pump motor are in motor mode, the electro-hydraulic reversing valve automatically switches to the lower working position, the control unit controls the oil circuit inside the valve to remain connected, the rodless cavity of the asymmetric actuator is squeezed out of the liquid by the load inertia force, the electricity generated by the electric generator is rectified and inverted by the motor controller, and the electric energy is recovered to the power battery unit through high-voltage distribution, and when the load reverses and brakes the rodless cavity to discharge liquid, part of the oil at the B1 port of the main pump motor enters the rod cavity of the asymmetric actuator, and the excess oil of the accumulator assists in entering through the B2 port of the volume compensation pump motor and exiting through the A2 port of the volume compensation pump motor and flowing back to the oil tank.

[0018] The beneficial effects of this invention are as follows: Compared with existing technologies, this application effectively solves the problem of system oscillation caused by flow differences between the two chambers of an asymmetric actuator. The energy recovery unit can recover potential energy, significantly extending the device's operating life. The automatic switching function of the electro-hydraulic reversing valve effectively reduces system response time, meeting the high-frequency motion requirements of construction machinery.

[0019] Additional aspects and advantages of the present invention will be set forth in part in the description which follows and, in part, will be obvious from the description which follows, or may be learned by practice of the present invention. BRIEF DESCRIPTION OF THE DRAWINGS

[0020] Figure 1 It is a structural diagram of the asymmetric actuator electro-hydraulic control system of the present invention; Figure 2 is a flow chart of the vertical working condition (control lever backward) of the present invention; Figure 3is a flow chart of the vertical working condition (control lever forward) of the present invention; Figure 4 is a flow chart of the vertical working condition (control lever reset) of the present invention; Figure 5 is a flow chart of the horizontal working condition (joystick forward) of the present invention; Figure 6 It is a flow chart of the horizontal working condition (control lever backward) of the present invention.

[0021] Reference numerals: 1. Electric generator; 2. Motor controller; 3. High-voltage distributor; 4. Main pump motor; 5. Volume compensation pump motor; 6. Control unit; 7. Electro-hydraulic reversing valve; 8. Second pressure sensor; 9. Overflow valve; 10. Second safety oil supply valve; 11. First safety oil supply valve; 12. Accumulator; 13. Holding valve; 14. Power battery unit; 15. Charging port; 16. Rod chamber; 17. Rodless chamber; 18. Load; 19. Fuel tank; 20. Displacement sensor; 21. First pressure sensor. DETAILED DESCRIPTION

[0022] The following describes embodiments of the present invention in detail, examples of which are shown in the accompanying drawings, wherein the same or similar reference numerals throughout represent the same or similar elements or elements having the same or similar functions. The embodiments described below with reference to the accompanying drawings are exemplary and are intended to be used to explain the present invention, and are not to be construed as limiting the present invention.

[0023] Furthermore, the terms "first" and "second" are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of the technical features being referred to. Thus, a feature identified as "first" or "second" may explicitly or implicitly include one or more of the features. In the description of the present invention, "plurality" means two or more, unless otherwise specifically defined.

[0024] Reference below Figures 1 to 6 An asymmetric actuator electro-hydraulic control system according to an embodiment of the present invention is described.

[0025] An embodiment of the present application discloses an asymmetric actuator electro-hydraulic control system, comprising: an energy supply and storage unit, a hydraulic control unit 6, a control unit 6 and an asymmetric actuator.

[0026] The energy supply and energy storage unit, the hydraulic control unit 6 and the asymmetric actuator are all controlled by the control unit 6; the energy supply and energy storage unit includes a power battery unit 14, a high-voltage distributor 3, a motor controller 2 and an electric generator 1 which are electrically connected in sequence; the hydraulic control unit 6 includes a main pump motor 4, a volume compensation pump motor 5, an electro-hydraulic reversing valve 7, a holding valve 13, an oil tank 19 and an accumulator 12, the main pump motor 4 and the volume compensation pump motor 5 are respectively connected to the electric generator 1 in a transmission manner, the A1 port of the main pump motor 4 is connected to the oil inlet of the holding valve 13, and the oil outlet of the holding valve 13 is connected to the M port of the rodless chamber 17 of the asymmetric actuator. The control port of the holding valve 13 is connected to the control unit 6 for signal communication. The B1 port of the main pump motor 4 is connected to the N port of the rod chamber 16 of the asymmetric actuator. The A2 port of the displacement compensation pump motor 5 is connected to the oil tank 19. The B2 port of the displacement compensation pump motor 5 is connected to the accumulator 12 and the oil inlet of the electro-hydraulic reversing valve 7, respectively. The first working oil port of the electro-hydraulic reversing valve 7 is connected to the oil circuit between the A1 port of the main pump motor 4 and the oil inlet of the holding valve 13 through a pipeline. The second working oil port of the electro-hydraulic reversing valve 7 is connected to the oil circuit between the B1 port of the main pump motor 4 and the N port of the rod chamber 16 of the asymmetric actuator through a pipeline. The power battery unit 14 can be replenished with electricity through the charging port 15 of the high-voltage power distribution.

[0027] The energy supply and storage unit is the energy hub that achieves bidirectional conversion between electrical and mechanical energy. It controls the electric generator 1 between motor and generator modes via a bidirectional inverter. The main pump motor 4 in the hydraulic control unit 6 is a variable hydraulic mechanism that drives the actuator's main oil circuit. The electro-hydraulic reversing valve 7 is a flow distribution device with pressure feedback that automatically switches the oil circuit connectivity based on the system pressure differential. The holding valve 13 is a hydraulically controlled one-way valve controlled by an electrical signal. It maintains oil circuit conductivity in the de-energized state and shuts off the oil circuit to lock the actuator position when powered on.

[0028] Specifically, the system eliminates the overflow loss of the traditional open system through a closed hydraulic circuit. The main pump motor 4 directly drives the main oil circuit of the actuator, and the compensation pump motor cooperates with the accumulator 12 to compensate for the flow difference between the two chambers. When the actuator is extended, the oil intake of the rodless chamber 17 is greater than the oil discharge of the rod chamber 16, and the compensation pump replenishes the insufficient flow from the accumulator 12; when retracted, the electro-hydraulic reversing valve 7 switches the direction of the oil circuit and guides the excess oil back to the oil tank 19. The control unit 6 monitors the pressure sensor signal in real time, dynamically adjusts the pump motor displacement and the reversing valve position, and maintains the system flow balance. The electric generator 1 consumes electrical energy when driving the pump motor, and switches to generator mode when the actuator brakes or falls due to gravity, converting hydraulic energy into electrical energy and feeding it back to the battery.

[0029] Compared to existing technologies, traditional valve-controlled systems require additional compensating cylinders or complex diverter valves under asymmetric operating conditions. This solution achieves dynamic flow balance through the coordinated control of a dual-pump structure and a reversing valve. Compared to a single-pump control system, the compensating pump introduced in this design significantly reduces reliance on the control accuracy of the main pump. Regarding energy management, traditional open-loop systems suffer from high overflow losses, while this solution's closed-loop system, combined with an energy recovery unit, significantly improves system efficiency.

[0030] Through the above technical solution, this application effectively solves the system oscillation problem caused by the flow difference between the two chambers of the asymmetric actuator. The energy recovery unit can recover potential energy, significantly extending the device's operating life. The automatic switching function of the electro-hydraulic reversing valve 7 effectively reduces system response time, meeting the high-frequency motion requirements of construction machinery.

[0031] In some embodiments, for example Figure 1 As shown, the electric energy stored in the power battery unit 14 is distributed to the motor controller 2 through the high-voltage distributor 3, and the DC power is converted into AC after being inverted to drive the electric generator 1 to output power. At the same time, the electric energy generated by the electric generator 1 is converted into DC after being inverted into AC by the motor controller 2 and then recovered to the power battery unit 14 through high-voltage distribution for storage.

[0032] Among them, the power battery unit 14 is an energy storage device for storing and releasing electrical energy. Its function is to provide basic energy for the system and recover regenerative energy. The high-voltage distributor 3 is an electric power control device that realizes the bidirectional distribution of electric energy. It is responsible for transmitting the electric energy of the power battery unit 14 to the motor controller 2 and transmitting the recovered energy back to the battery unit. The motor controller 2 is a power regulating device that realizes the conversion of AC and DC power. It can invert DC power into AC power under driving conditions and rectify AC power into DC power under power generation conditions. The electric generator 1 is an electromechanical conversion device with dual-mode operation of motoring and power generation. It converts electrical energy into mechanical energy under driving conditions and converts mechanical energy into electrical energy under power generation conditions.

[0033] Specifically, under driving conditions, the DC power stored in the power battery unit 14 is transmitted to the motor controller 2 via the distribution lines of the high-voltage distributor 3. It is then converted into three-phase AC power by the inverter module to drive the electric generator 1, which then acts as a motor to output mechanical power. Under energy recovery conditions, the electric generator 1, driven by external mechanical energy, generates three-phase AC power, which is converted into DC power by the rectifier module of the motor controller 2. This power is then fed back to the power battery unit 14 through the reverse channel of the high-voltage distributor 3 for storage. This process establishes a closed-loop energy management system through a bidirectional power path, enabling the motor controller 2 to have AC / DC bidirectional conversion capabilities, the high-voltage distributor 3 to achieve forward energy transmission and reverse energy recovery, and the power battery unit 14 to act as an energy hub to store and release electrical energy.

[0034] Through the above-mentioned technical solution, the present application achieves seamless switching between drive and power generation modes for the electric generator 1, establishes a bidirectional flow path for electrical energy, and solves the energy waste problem caused by unidirectional energy flow in traditional systems. This technical solution enables the system to effectively convert the actuator's downward potential energy and braking kinetic energy into electrical energy storage, forming a complete energy closed-loop control and significantly improving the overall energy utilization efficiency of the electro-hydraulic system.

[0035] Furthermore, the electric generator 1 includes a motor output working state and a motor power generation working state; when the electric generator 1 is in the motor output working state, the electric generator 1 drives the main pump motor 4 and the volume compensation pump motor 5 to be in pump mode; when the main pump motor 4 and the volume compensation pump motor 5 are in motor mode, the main pump motor 4 and the volume compensation pump motor 5 drive the electric generator 1 to work in the motor power generation working state.

[0036] The motor output mode refers to the electric generator 1 operating as a motor, converting electrical energy into mechanical energy to drive the hydraulic pump. The motor generation mode refers to the electric generator 1 operating as a generator, converting mechanical energy into electrical energy and feeding it back to the energy storage unit. The main pump motor 4 operating in pump mode refers to the hydraulic element operating as a hydraulic pump, converting mechanical energy into hydraulic energy to output pressurized oil. The main pump motor 4 operating in motor mode refers to the hydraulic element operating as a hydraulic motor, converting hydraulic energy into mechanical energy to output torque.

[0037] Specifically, when the asymmetric actuator is in active drive mode, the control unit 6 detects a positive swing angle signal, triggering the motor generator 1 to enter motor output mode. At this point, the motor generator 1 drives the main pump motor 4 and the displacement compensation pump motor 5 to rotate synchronously. The pressure oil output by these two pumps acts on the rodless chamber 17 and rod chamber 16 of the actuator, respectively. When the actuator generates reverse energy under the action of the load 18, the inlet oil pressure of the main pump motor 4 drives it into motor mode, driving the motor generator 1 to rotate and generate electricity. A negative swing angle signal triggers the control unit 6 to cut off the motor drive current and switch to the power generation feedback circuit. The main pump motor 4 and the displacement compensation pump motor 5 operate in parallel, forming a dual-motor drive structure during the energy recovery phase, improving energy conversion efficiency. The control unit 6 automatically selects energy output or recovery mode by monitoring the swing angle direction and pressure sensor signals in real time.

[0038] Through the above technical solution, the present application realizes the bidirectional intelligent switching between hydraulic drive and energy recovery, effectively recovering the potential energy of the actuator during the descent process and the kinetic energy of the braking process. The parallel structure of the two pump motors provides redundant driving capabilities in the energy output stage and forms a composite power generation unit in the recovery stage. The swing angle state detection mechanism ensures the real-time and accuracy of the working mode switching and avoids power loss during the energy conversion process. This bidirectional energy conversion system is particularly suitable for frequent start-stop and large inertia load scenarios, significantly reducing the overall energy consumption of the system.

[0039] In some embodiments, for example Figure 1 As shown, the electro-hydraulic reversing valve 7 is a three-position, three-way solenoid reversing valve including an upper position, an initial position, and a lower position. The control ports on both sides of the electro-hydraulic reversing valve 7 are both signal-connected to the control unit 6. When the electro-hydraulic reversing valve 7 is in the upper position, the oil inlet of the electro-hydraulic reversing valve 7 is connected to the first working oil port of the electro-hydraulic reversing valve 7. At this time, the oil circuit between the oil inlet of the electro-hydraulic reversing valve 7 and the A1 port of the main pump motor 4 and the oil inlet of the holding valve 13 is in a connected state. When the electro-hydraulic reversing valve 7 is in the initial position, the oil inlet of the electro-hydraulic reversing valve 7 and the first working oil port and the second working oil port of the electro-hydraulic reversing valve 7 are all in a blocked state. When the electro-hydraulic reversing valve 7 is in the lower position, the oil inlet of the electro-hydraulic reversing valve 7 is connected to the second working oil port of the electro-hydraulic reversing valve 7. At this time, the oil circuit between the oil inlet of the electro-hydraulic reversing valve 7 and the B1 port of the main pump motor 4 and the N port of the rod chamber 16 of the asymmetric actuator is in a connected state.

[0040] Among them, the three-position three-way solenoid directional valve is an electromagnetic control valve with three working positions and three passages. It can be specifically implemented by a sliding valve type directional valve with an electromagnetic drive mechanism and a spring return structure. This structure allows the valve core movement direction to be controlled by an electromagnetic signal; the upper working position refers to the oil circuit connection state formed when the valve core moves to the first working position, and this position establishes a rodless chamber 17 compensation channel; the initial position refers to the oil circuit cut-off state when the valve core is in the neutral position, and this state forms oil circuit isolation; the lower working position refers to the oil circuit connection state formed when the valve core moves to the second working position, and this position establishes a rod chamber 16 compensation channel.

[0041] Specifically, when it is detected that the pressure at the A1 port of the main pump motor 4 increases, the hydraulic pressure acts on the reversing valve core to push it to the lower working position, so that the compensation oil enters the B1 port oil circuit of the main pump motor 4 through the second working oil port; when it is detected that the pressure at the B1 port of the main pump motor 4 is abnormal, the control unit 6 directly sends an electromagnetic signal to drive the valve core to switch to the upper working position, so that the compensation oil enters the A1 port oil circuit through the first working oil port; in the non-action stage, the reversing valve automatically maintains the initial position and cuts off all compensation oil circuits; in the emergency shutdown state, the control unit 6 is forced to switch to the initial position to form a physical blockage; through the dual driving mechanism of pressure sensing and electromagnetic control, rapid response and redundant control of oil circuit switching are achieved.

[0042] Through the above technical solution, the present application realizes real-time flow difference compensation between the two chambers of the asymmetric actuator. During the rising stage of the load 18, the oil in the rod chamber 16 is supplemented through the lower workstation, and during the falling stage of the load 18, the oil in the rodless chamber 17 is compensated through the upper workstation; at the same time, the pressure shock caused by the sudden opening or closing of the oil circuit during the switching process is avoided.

[0043] In some embodiments, for example Figure 1 As shown, a first pressure sensor 21 is provided on the oil circuit between the A1 port of the main pump motor 4 and the oil inlet of the holding valve 13, and a second pressure sensor 8 is provided on the oil circuit between the B1 port of the main pump motor 4 and the N port of the rod chamber 16 of the asymmetric actuator. Both the first pressure sensor 21 and the second pressure sensor 8 are connected to the control unit 6 signal.

[0044] The first pressure sensor 21 is a device for detecting the oil inlet pressure of the rodless chamber 17. Its function is to obtain real-time pressure data of the oil circuit between the main pump motor 4 and the holding valve 13. The second pressure sensor 8 is a device for detecting the oil circuit pressure of the rod chamber 16. It is used to monitor the oil pressure status between the main pump motor 4 and the asymmetric actuator rod chamber 16.

[0045] Specifically, when the asymmetric actuator is in operation, due to the difference in cross-sectional area between the rodless chamber 17 and the rod chamber 16, the pressure in the two chambers' oil circuits presents an asymmetric distribution. The first pressure sensor 21 collects the pressure signal of the oil inlet circuit of the rodless chamber 17 in real time, and the second pressure sensor 8 synchronously monitors the pressure parameters of the oil circuit of the rod chamber 16. The two data are transmitted to the control unit 6. The control unit 6 identifies the pressure imbalance state by comparing the dynamic changes in the pressure values of the two chambers, such as the pressure fluctuations that occur when the load 18 suddenly changes or when the direction is reversed. Based on the pressure difference, the control unit 6 can adjust the displacement parameters of the main pump motor 4 to balance the flow demand, and at the same time, switch the oil circuit through the electro-hydraulic reversing valve 7 to compensate for the flow difference. In the case of an abnormality in the holding valve 13 or a pipeline leak, the gradient change data of the pressure sensor can be used for fault diagnosis. For example, when the pressure in the oil circuit of the rodless chamber 17 drops abnormally, the control unit 6 can trigger an alarm and cut off the hydraulic circuit.

[0046] Through the above-mentioned technical solution, this application solves the problem of oil circuit pressure imbalance caused by the difference in cross-sectional area between the two chambers of an asymmetric actuator, and realizes real-time pressure monitoring and dynamic compensation control at key nodes of the hydraulic system. The synchronous collection and analysis of pressure data enables the system to quickly respond to load changes, effectively suppress pressure shocks and vibrations, and improve the smoothness of actuator movement. The dual-sensor configuration also provides data support for the early identification of system failures. For example, in the event of oil circuit leakage or valve jamming, the abnormal pressure signal can trigger the protection mechanism.

[0047] In some embodiments, for example Figure 1 As shown, the telescopic rod of the asymmetric actuator is connected to a load 18. The telescopic movement of the asymmetric actuator's telescopic rod causes the load 18 to extend and retract. A displacement sensor 20 is provided at the end of the load 18, and the displacement sensor 20 is connected to the control unit 6 for signal communication. The displacement sensor 20 is a detection device used to detect displacement changes of the load 18 in real time. Installed at the connection between the load 18 and the actuator's telescopic rod, the displacement sensor 20 detects changes in the linear or angular displacement of the load 18, generates an electrical signal, and transmits it to the control unit 6 to form a closed-loop feedback loop.

[0048] Specifically, the extension or retraction of the load 18 is driven by the difference in the flow rate of the hydraulic oil in the two chambers of the asymmetric actuator, and the difference in the cross-sectional area of the two chambers leads to different flow requirements. The displacement sensor 20 collects the displacement of the load 18 in real time and feeds it back to the control unit 6. The control unit 6 determines the flow compensation requirement based on the displacement change rate and direction. When the load 18 is in the acceleration or deceleration stage, the displacement sensor 20 detects the displacement change trend, triggers the control unit 6 to adjust the position switching of the electro-hydraulic reversing valve 7, and controls the accumulator 12 and the volume compensation pump motor 5 to work together to compensate for the flow difference caused by the difference in the cross-sectional area of the two chambers. During the braking or inertial motion of the load 18, the signal of the displacement sensor 20 is compared with the safe displacement threshold preset by the control unit 6, and the energy recovery mode is automatically started. By adjusting the swing angle of the main pump motor 4, the hydraulic energy is converted into electrical energy and stored back in the power battery unit 14.

[0049] Through the above-described technical solution, the present application is able to monitor the displacement state of load 18 in real time during its movement, accurately identifying flow compensation requirements and energy recovery opportunities, and avoiding pressure fluctuations or energy waste caused by differences in the cross-sectional areas of the two chambers. The continuous position signal provided by displacement sensor 20 enables control unit 6 to dynamically adjust the pump motor swing angle and reversing valve position, ensuring flow balance in the hydraulic circuit while improving the efficiency of potential and kinetic energy recovery.

[0050] In some embodiments, for example Figure 1 As shown, control unit 6 includes a joystick with a button located directly above it. The backward angle of the joystick is linearly proportional to the speed at which load 18 rises, while simultaneously driving the motor. The forward angle of the joystick is linearly proportional to the speed at which load 18 descends, while simultaneously driving the motor. The stroke of the button pressed directly above the joystick is linearly proportional to the swing angle of the control pump from 0 to the maximum negative swing angle, while simultaneously driving load 18 downward without power. When the joystick is naturally reset to the neutral position without any operation and the button reset is inactive, electro-hydraulic reversing valve 7 is in its initial position, and the oil circuit is in a closed state. The forward, backward, and button operations of the joystick are independent of each other and do not involve any combined actions. Priority is given to the first operation performed; that is, the next operation instruction is not executed unless the first operation is reset.

[0051] The linear symmetry between the rearward angle change of the joystick and the load 18's rising speed refers to the linear relationship between the handle's backward stroke and the hydraulic pump's positive swing angle adjustment. The linear symmetry between the button's pressed stroke and the control pump's swing angle from 0 to the maximum negative angle refers to the linear relationship between the button's pressed depth and the hydraulic pump's reverse swing angle adjustment. Prioritizing the first operation refers to the operation signal processing module setting a command latch mechanism. Upon detecting any active operation signal, all other operation channels are locked until the current operation is reset and unlocked.

[0052] Specifically, when the operator pulls the joystick backward, the angle sensor generates a 0-100% proportional signal. Control unit 6 maps this signal into a hydraulic pump adjustment command from 0 to the maximum positive swing angle, driving the main pump to discharge oil in the positive direction, causing fluid to flow into the actuator's rodless chamber 17. At this point, motor controller 2 automatically matches the motor speed based on the swing angle signal, ensuring that the flow output corresponds linearly to the handle angle. If the operator subsequently accidentally presses a button or pushes the handle forward, control unit 6 blocks subsequent commands due to the initial reset, maintaining the current pump swing angle control state. When the handle returns to the neutral position and the button remains inactive, control unit 6 outputs a neutral position signal, returning electro-hydraulic reversing valve 7 to its initial position while keeping valve 13 closed, blocking the oil flow. In the unpowered drive mode, 0-100% of the button's downward stroke corresponds to the hydraulic pump adjusting from 0 to the maximum negative swing angle. The gravity of load 18 compresses the actuator to discharge oil, driving the hydraulic motor to rotate and generate electricity. The generated power increases linearly with the button's travel, and the accumulator 12 compensates for the flow difference between the two chambers through a volume compensation circuit.

[0053] Through the above technical solution, the present application effectively prevents actuator action conflicts caused by complex operations, ensuring the complete execution of single operation instructions; realizes linear controllable falling speed of load 18 under non-powered drive conditions, and converts gravitational potential energy into electrical energy storage; automatically cuts off the oil circuit when the operating handle is reset, preventing the actuator from drifting due to pressure leakage, thereby improving system safety and energy utilization efficiency.

[0054] The present invention also proposes an asymmetric actuator electro-hydraulic control method, which is applied to the asymmetric actuator electro-hydraulic control system in the above-mentioned embodiment, including: a vertical working condition control method and a horizontal working condition control method. The vertical working condition control method includes the control of the joystick of the operating handle when it is backward, the control of the joystick of the operating handle when it is forward, and the control when the button of the joystick of the operating handle is pressed to reset the state. The horizontal working condition control method includes the control of the joystick of the operating handle when it is forward and the control of the joystick of the operating handle when it is backward.

[0055] Among them, the vertical working condition control method refers to the directional control logic established for vertical motion scenarios with potential energy changes. Specifically, the forward pump mode of the main pump motor 4 can be triggered by pulling back the joystick to drive the load 18 to rise, and the electro-hydraulic reversing valve 7 can be linked to switch to the lower position to achieve oil circuit compensation. The button control mode refers to triggering the unpowered load 18 to descend by pressing the button when the joystick is reset. Specifically, the negative swing angle adjustment of the main pump motor 4 can be used to link the electric generator 1 to generate electricity and store potential energy. The horizontal working condition control method refers to the inertial control logic established for horizontal motion scenarios with kinetic energy changes. Specifically, the electro-hydraulic reversing valve 7 can be triggered to automatically switch positions by resetting the joystick, so that the inertial motion of the load 18 drives the main pump motor 4 to generate electricity and recover kinetic energy.

[0056] Specifically, in vertical operation, when the joystick is pulled back, the control unit 6 drives the main pump motor 4 in forward pump mode according to the swing angle signal to output high-pressure oil to the rodless chamber 17. At the same time, the electro-hydraulic reversing valve 7 switches to the lower position to form a compensation circuit, realizing the full recycling of the oil discharged from the rod chamber 16. When the joystick is pushed forward, the main pump motor 4 drives the rod chamber 16 in reverse pump mode to pump oil. The accumulator 12 compensates the flow difference of the oil discharged from the rodless chamber 17 through the volume compensation pump motor 5. When the button is pressed, the weight of the load 18 drives the main pump motor 4 to rotate in the opposite direction to generate electricity. At the same time, the electro-hydraulic reversing valve 7 switches to the lower position to form a closed oil circuit, converting potential energy into electrical energy for recovery. In horizontal operation, when the joystick is reset, the inertia of the load 18 squeezes the actuator chamber to discharge oil, driving the main pump motor 4 to generate electricity. At the same time, the electro-hydraulic reversing valve 7 automatically switches positions according to pressure changes to form a compensation circuit, eliminating the pressure shock caused by flow imbalance.

[0057] Through the above technical solution, the present application realizes overflow-free energy conversion during the lifting and lowering process of the load 18, eliminating the pressure shock caused by the flow difference in the traditional system; converts the inertial kinetic energy into electrical energy storage during the braking stage, so as to improve the energy utilization rate of the system; realizes precise adjustment of the actuator movement speed through the linear proportional control of the joystick action and the pump swing angle; automatically matches the oil circuit compensation method in horizontal operation to ensure the flow balance during the inertial movement of the load 18.

[0058] Furthermore, during vertical operation, the control process when the joystick is moved backward includes: startup, equipment status self-check, and backward movement of the joystick. The control unit 6 then linearly increases the pump's swing angle from 0 to its maximum positive swing angle through electro-hydraulic proportional control. Simultaneously, upon receiving a signal indicating the swing angle is greater than 0, the control unit 6 controls the motor controller 2 to drive the motor. This places the motor generator 1 in motor output mode, the main pump motor 4 and the displacement compensation pump motor 5 in pump mode, and the motor generator 1 outputs mechanical energy to drive the main pump motor 4 and the displacement compensation pump motor 5. Due to the pressure in the pipeline between port A1 of the main pump motor 4 and port M of the rodless chamber 17, the electro-hydraulic reversing valve 7 automatically switches to the lower position and reports its current status to the control unit 6. Simultaneously, the displacement sensor 20, the second pressure sensor 8, and the first pressure sensor 21 transmit pressure signals to the control unit 6 to monitor the normal operation of the electro-hydraulic reversing valve 7. At this point, the control unit 6 maintains the oil circuit within the holding valve 13 open, ensuring that the oil inlet and outlet of the holding valve 13 are in a continuous state. The main pump motor 4 controls the high-pressure oil to flow out from the A1 port of the main pump motor 4. The high-pressure oil provided by the A1 port of the main pump motor 4 can enter the M port of the rodless chamber 17 of the asymmetric actuator through the holding valve 13, control the liquid to flow into the rodless chamber 17 of the asymmetric actuator, and cause the load 18 to rise. When the load 18 of the rodless chamber 17 increases, the low-pressure oil discharged from the rod chamber 16 of the asymmetric actuator flows entirely to the B1 port of the main pump motor 4 through the pipeline; due to the different cross-sectional areas of the two chambers of the asymmetric actuator, unless the low-pressure oil discharged from the rod chamber 16 of the symmetric actuator enters through the B1 port of the main pump motor 4 and exits through the A1 port of the main pump motor 4, all of it is supplied to the rodless chamber 17 of the asymmetric actuator, the oil circuit from the B2 port of the volume compensation pump motor 5 to the B1 port of the main pump motor 4 is connected, and the accumulator 12 assists the A2 port of the volume compensation pump motor 5 to absorb oil from the oil tank 19 and exit through the B2 port of the volume compensation pump motor 5, and flows to the B1 port of the main pump motor 4 through the electro-hydraulic reversing valve 7. At this time, the flow rate of the B1 port of the main pump motor 4 is the same as that of the A1 port of the main pump motor 4 after oil compensation by the volume compensation pump motor 5.

[0059] During vertical operation, the forward-moving joystick control includes: power-up, a self-check of the equipment status, and the forward movement of the joystick. The control unit 6 then controls the pump's electro-hydraulic proportional control, increasing its swing angle linearly from 0 to its maximum negative angle. Simultaneously, upon receiving a signal indicating the swing angle is less than 0, the control unit 6 controls the motor controller 2 to drive the motor. This places the motor generator 1 in motor output mode, while the main pump motor 4 and the displacement compensation pump motor 5 in pump mode. The motor generator 1 outputs mechanical energy to drive the main pump motor 4 and the displacement compensation pump motor 5. Due to the pressure in the pipeline between port B1 of the main pump motor 4 and port N of the rod chamber 16, the electro-hydraulic reversing valve 7 automatically switches to the upper position and reports its current status to the control unit 6. Simultaneously, the displacement sensor 20, the second pressure sensor 8, and the first pressure sensor 21 transmit pressure signals to the control unit 6 to monitor the normal operation of the electro-hydraulic reversing valve 7. At this point, the control unit 6 maintains the oil circuit within the holding valve 13 open, ensuring that the oil inlet and outlet of the holding valve 13 are in a continuous state. As the load 18 of the rod chamber 16 decreases, the motor-generator 1 enters the motor output mode, and the main pump-motor 4 and the displacement compensator pump-motor 5 enter pump mode. The motor-generator 1 outputs mechanical energy to drive the main pump-motor 4 and the displacement compensator pump-motor 5. The main pump-motor 4 controls the high-pressure oil to flow from port B1 of the main pump-motor 4 into the rod chamber 16 at port N of the asymmetric actuator, thereby decreasing the load 18 of the rod chamber 16. As the load 18 of the rod chamber 16 decreases, the oil discharged from the rodless chamber 17 of the asymmetric actuator flows through the holding valve 13 to port A1 of the main pump-motor 4. Due to the different cross-sectional areas of the two chambers in the asymmetric actuator, port B2 of the displacement compensator pump-motor 5 connects to the rodless chamber 17 of the asymmetric actuator. The accumulator 12 assists in the flow of excess oil, which enters port B2 of the displacement compensator pump-motor 5 and exits port A2 of the displacement compensator pump-motor 5, returning to the oil tank 19. After the flow is divided, the flow rate of the flow divided from the B1 port of the main pump motor 4 is the same as the flow rate of the A1 port of the main pump motor 4.

[0060] Under vertical working conditions, the control when the button is pressed in the reset state of the joystick of the operating handle includes: power-on, equipment status self-check, the stroke of the button pressed directly above the handle is linearly symmetrical with the swing angle of the electro-hydraulic proportional control pump from 0 to the maximum negative swing angle, the unpowered drive load 18 falls, and the control unit 6 controls the oil circuit inside the valve 13 to remain connected, that is, the oil inlet of the valve 13 and the oil outlet of the valve 13 are in a conductive state. The asymmetric actuator's rodless chamber 17 is subjected to the gravity of the load 18, forcing the oil within it out of the chamber. Due to the pressure in the pipeline between port A1 of the main pump motor 4 and the rodless chamber 17, the electro-hydraulic directional valve 7 automatically switches to the lower position and reports its current state to the control unit 6. The control unit 6 then controls the pump's slew angle from 0 to its maximum negative slew angle, increasing linearly with the amount of button press travel. The main pump motor 4 and the displacement compensation pump motor 5 enter motor mode. Upon receiving a signal indicating the slew angle is less than 0, the motor generator 1 enters generator mode. Simultaneously, the displacement sensor 20, the second pressure sensor 8, and the first pressure sensor 21 transmit pressure signals to the control unit 6 to monitor the proper operation of the electro-hydraulic directional valve 7. The oil discharged from the asymmetric actuator's rodless chamber 17 flows through the holding valve 13 to port A1 of the main pump motor 4. The main pump motor 4 outputs mechanical energy, driving the motor generator 1 to generate electricity, thereby reducing the load 18 at the discharge of the rodless chamber 17. The electricity generated by the electric generator 1 is rectified and inverted by the motor controller 2, and then recovered via high-voltage distribution to the power battery unit 14. When the load 18 of the rodless chamber 17 decreases, some of the oil at port B1 of the main pump motor 4 enters the rod chamber 16 of the asymmetric actuator. Due to the different cross-sectional areas of the two chambers in the asymmetric actuator, the oil circuit from port B2 of the displacement compensation pump motor 5 to port B1 of the main pump motor 4 is connected. The accumulator 12 assists in the flow of excess oil into port B2 of the displacement compensation pump motor 5 and out of port A2 of the displacement compensation pump motor 5, returning to the oil tank 19. At this point, the total flow rate diverted from port B1 of the main pump motor 4 to the rod chamber 16 of the asymmetric actuator and back to the oil tank 19 is equal to the flow rate at port A1 of the main pump motor 4.

[0061] When the actuator is in vertical operation, after pressing the emergency stop button, the power input of the power unit is cut off, and the valve 13 is kept disconnected. The pump motor swing angle is reset to 0, and the electro-hydraulic reversing valve 7 is switched to the neutral state. To ensure operational safety, the neutral state of the electro-hydraulic reversing valve 7 is controlled by the control unit 6 at this time.

[0062] Specifically, during the rising phase of the load 18, the main pump motor 4 runs forward to deliver high-pressure oil to the rodless chamber 17, and the oil discharged from the rod chamber 16 forms a closed cycle through the main pump motor 4. The volume compensation pump motor 5 replenishes oil from the accumulator 12 to compensate for the area difference between the two chambers. During the falling phase of the load 18, the main pump motor 4 runs in the reverse direction to pressurize the rod chamber 16, and the oil discharged from the rodless chamber 17 is diverted to the oil tank 19 through the electro-hydraulic reversing valve 7 to avoid excessive system pressure. During the unpowered slow descent phase, the gravity of the load 18 drives the main pump motor 4 to reverse and generate electricity, and the accumulator 12 compensates for the oil gap in the rod chamber 16 through the volume compensation pump motor 5. This process monitors the oil circuit pressure in real time through a pressure sensor. When it is detected that the pressure difference between the A1 port and the B1 port of the main pump exceeds the set threshold, the control unit 6 automatically adjusts the position of the electro-hydraulic reversing valve 7 to ensure flow balance.

[0063] Compared to existing technologies, traditional vertical operation systems use throttle or balancing valves to control speed when the load 18 is lowered, resulting in energy waste and the inability to recover potential energy. This solution, however, converts gravitational potential energy into stored electrical energy through pump-motor mode switching and a volume compensation circuit. Compared to systems using independent charge pumps, this solution reduces the number of hydraulic components by connecting the main pump and compensation pump in series, while utilizing the accumulator 12 to achieve instantaneous high-flow compensation. Compared to solutions using mechanical brakes, this technology achieves smooth braking without mechanical wear through the synergistic effect of the hydraulic circuit and the electronic control unit.

[0064] Through the above-mentioned technical solution, this application achieves multi-mode precision control of asymmetric actuators in vertical operations, resolving the flow imbalance problem caused by the difference in cross-sectional area between the two chambers. A closed loop is formed during the rising phase of load 18 to reduce energy loss. During the descending phase of load 18, oil flow is diverted to avoid pressure shock, and potential energy is recovered during the unpowered descent phase. In particular, the synergistic effect of linear control of the pump swing angle and automatic switching of the volume compensation valve improves system energy utilization while ensuring control accuracy.

[0065] Furthermore, during horizontal operation, the forward-moving control of the joystick includes: power-up and a self-check of the equipment status. When the joystick is in the forward-moving state, the pump motor's swing angle is in the positive swing state. At this point, the joystick is reset, and control unit 6 receives a reset signal, controlling motor controller 2. The electric generator 1 is in power generation mode, and the main pump motor 4 and volume compensation pump motor 5 are in motor mode. At this point, the flow direction remains unchanged, and the swing angle remains unchanged. Simultaneously, due to the pressure in the pipeline between port B1 of the main pump motor 4 and port N of the rod chamber 16, the electro-hydraulic reversing valve 7 automatically switches to the upper position and reports its current status to control unit 6. The displacement sensor 20, second pressure sensor 8, and first pressure sensor 21 transmit pressure signals to control unit 6 to assist in monitoring the normal operation of the electro-hydraulic reversing valve 7. At this point, control unit 6 controls the oil circuit within valve 13 to remain connected, ensuring that the oil inlet and outlet of valve 13 are in a continuous state. The inertial force of load 18 squeezes fluid out of the rod chamber 16 of the asymmetric actuator. This fluid is then delivered to port B1 of the main pump-motor 4, driving the motor-generator 1. The electricity generated by the motor-generator 1 is rectified and inverted by the motor controller 2, and then recovered via high-voltage distribution to the power battery unit 14. When load 18 applies forward braking, the fluid in port A1 of the main pump-motor 4 enters the rodless chamber 17 of the asymmetric actuator. Due to the different cross-sectional areas of the two chambers in the asymmetric actuator, the pressure at port B1 of the main pump-motor 4 causes the control unit 6 to activate the electro-hydraulic reversing valve 7 to switch to the upper position. Port B2 of the displacement compensation pump-motor 5 communicates with the rodless chamber 17 of the asymmetric actuator. The accumulator 12 assists the displacement compensation pump-motor 5 in transferring fluid from the oil tank 19 to the rodless chamber 17 of the asymmetric actuator. At this time, the total amount of the liquid outflow of the rod chamber 16 of the asymmetric actuator and the amount of compensation oil in the oil tank 19 is equal to the total amount of liquid inflow into the rodless chamber 17 of the asymmetric actuator.

[0066] Under horizontal working conditions, the control of the joystick of the operating handle when it is in the backward direction includes: starting the machine, self-checking the equipment status, and when the handle is in the backward state (refer to Figure 3Load 18 is in a power-down state), the pump motor's swing angle is in a negative swing angle state, and the motor and pump are in energy output mode. At this time, the joystick is reset, and control unit 6 receives a reset signal, regulating motor controller 2. Electric generator 1 is in power generation mode, while main pump motor 4 and volume compensation pump motor 5 are in motor mode. At this time, the flow direction remains unchanged, and the pump's swing angle does not change when it switches to motor mode. At the same time, due to the pressure in the pipeline between port A1 of main pump motor 4 and port M of rodless chamber 17, electro-hydraulic reversing valve 7 automatically switches to the lower position and feeds back the current state to control unit 6. Displacement sensor 20, second pressure sensor 8, and first pressure sensor 21 transmit pressure signals to control unit 6 to assist in monitoring whether electro-hydraulic reversing valve 7 is operating normally. At this time, control unit 6 controls the oil circuit inside valve 13 to remain connected, that is, the oil inlet of valve 13 and the oil outlet of valve 13 are in a conductive state. The inertial force of load 18 squeezes fluid out of the rodless chamber 17 of the asymmetric actuator. The fluid discharged from the rod chamber 16 of the asymmetric actuator is then delivered to port A1 of the main pump motor 4, driving the main pump motor 4 and the motor generator 1. The electricity generated by the motor generator 1 is rectified and inverted by the motor controller 2, and then recovered via high-voltage distribution to the power battery unit 14. When load 18 applies reverse braking, fluid is discharged from the rodless chamber 17, and some of the fluid at port B1 of the main pump motor 4 enters the rod chamber 16 of the asymmetric actuator. Due to the different cross-sectional areas of the two chambers in the asymmetric actuator and the pressure at port A1 of the main pump motor 4, the control unit 6 controls the electro-hydraulic reversing valve 7 to switch to the lower position. This connects the oil circuit from port B2 of the displacement compensating pump motor 5 to port B1 of the main pump motor 4. The accumulator 12 assists in collecting excess fluid, which enters port B2 of the displacement compensating pump motor 5 and exits port A2, returning to the oil tank 19. At this time, the total flow rate of the B1 port of the main pump motor 4 that is diverted to the rod chamber 16 of the asymmetric actuator and flows back to the oil tank 19 is the same as the flow rate of the A1 port of the main pump motor 4.

[0067] When the actuator is operating horizontally, after the brake is applied, valve 13 is held open, electro-hydraulic directional valve 7 switches to the neutral position, and the pump motor angle returns to zero. To ensure operational safety, the neutral position of electro-hydraulic directional valve 7 is controlled by control unit 6. If the emergency stop button is pressed, power input to the power unit is cut off, valve 13 is held open, the pump motor angle returns to zero, and electro-hydraulic directional valve 7 switches to the neutral position. To ensure operational safety, the neutral position of electro-hydraulic directional valve 7 is controlled by control unit 6.

[0068] Specifically, when load 18 continues to move backward due to inertia during horizontal operation, the joystick reset signal triggers control unit 6 to switch motor generator 1 to power generation mode. The main pump motor 4 and displacement compensation pump motor 5 switch from pump mode to motor mode, converting the hydraulic energy of the oil discharged from the asymmetric actuator's rodless chamber 17 into mechanical energy to drive the generator. This electrical energy is rectified and inverted before being stored in power battery unit 14, achieving kinetic energy recovery. After the electro-hydraulic reversing valve 7 switches to the lower position, the oil at port B1 of the main pump motor 4 is divided into two paths: one portion enters the rod chamber 16 to replenish the volume difference caused by the discharge of the rodless chamber 17, and the other portion flows back to the oil tank 19 through the displacement compensation pump motor 5. The accumulator 12 absorbs or releases oil in the event of sudden changes in oil pressure, coordinating with the displacement compensation pump motor 5 to adjust the oil volume and eliminate flow mismatches caused by the cross-sectional area difference between the two actuator chambers. Maintaining valve 13 remains open ensures continuous oil flow and avoids pressure shocks caused by sudden shutoffs.

[0069] Compared with existing technologies, traditional horizontal braking often uses a relief valve 9 or throttle valve to dissipate inertial kinetic energy, resulting in energy waste and the risk of hydraulic shock. This solution, however, directly converts hydraulic energy into stored electrical energy by switching the pump motor to motor mode. It also utilizes an accumulator 12 and a volume compensation circuit to dynamically adjust oil volume, recovering energy while maintaining stable system pressure. Existing valve-controlled systems rely on complex external control logic for flow compensation. This solution simplifies the control process and improves response speed by automatically switching the electro-hydraulic directional valve 7 and synergizing the accumulator 12.

[0070] Through the above technical solution, this application effectively solves the problems of kinetic energy recovery and pressure balance under horizontal braking conditions. The energy recovery mechanism converts the inertial kinetic energy of load 18 into electrical energy storage, extending the system's endurance. The synergistic effect of accumulator 12 and the volume compensation circuit eliminates the flow difference between the two chambers of the asymmetric actuator, avoiding mechanical shock caused by sudden pressure changes. Maintaining the conduction state of valve 13 ensures oil continuity during the braking process, making the deceleration process of load 18 smoother and more stable.

[0071] Other structures and operations of the asymmetric actuator electro-hydraulic control system and method according to the embodiments of the present invention are well known to those skilled in the art and will not be described in detail here.

[0072] In the description of this specification, the reference terms "one embodiment", "some embodiments", "example", "specific example", or "some examples" mean that the specific features, structures, materials or characteristics described in conjunction with the embodiment or example are included in at least one embodiment or example of the present invention. In this specification, the schematic representations of the above terms do not necessarily refer to the same embodiment or example. Moreover, the specific features, structures, materials or characteristics described can be combined in any one or more embodiments or examples in a suitable manner. In addition, those skilled in the art can combine and combine different embodiments or examples described in this specification and features of different embodiments or examples without contradiction.

[0073] While embodiments of the present invention have been shown and described, it will be appreciated by those skilled in the art that various changes, modifications, substitutions, and variations may be made to the embodiments without departing from the principles and spirit of the invention, and that the scope of the invention is defined by the claims and their equivalents.

Claims

1. An asymmetric actuator electro-hydraulic control system, characterized in that: include: Energy supply and energy storage unit, hydraulic control unit, control unit and asymmetric actuator; the energy supply and energy storage unit, the hydraulic control unit and the asymmetric actuator are all controlled by the control unit; the energy supply and energy storage unit includes a power battery unit, a high-voltage distributor, a motor controller and an electric generator that are electrically connected in sequence; the hydraulic control unit includes a main pump motor, a volume compensation pump motor, an electro-hydraulic reversing valve, a holding valve, an oil tank and an accumulator, the main pump motor and the volume compensation pump motor are respectively connected to the electric generator in a transmission manner, the A1 port of the main pump motor is connected to the oil inlet of the holding valve, and the oil outlet of the holding valve is connected to the asymmetric actuator The rodless chamber M port of the actuator is connected, the control port of the holding valve is connected to the control unit signal, the B1 port of the main pump motor is connected to the rod chamber N port of the asymmetric actuator; the A2 port of the volume compensation pump motor is connected to the oil tank, and the B2 port of the volume compensation pump motor is respectively connected to the accumulator and the oil inlet of the electro-hydraulic reversing valve, the first working oil port of the electro-hydraulic reversing valve is connected to the oil circuit between the A1 port of the main pump motor and the oil inlet of the holding valve through a pipeline, and the second working oil port of the electro-hydraulic reversing valve is connected to the oil circuit between the B1 port of the main pump motor and the rod chamber N port of the asymmetric actuator through a pipeline.

2. The asymmetric actuator electro-hydraulic control system according to claim 1, characterized in that: The electric energy stored in the power battery unit is distributed to the motor controller through the high-voltage distributor, and the DC power is converted to AC after being inverted to drive the electric generator to output power. At the same time, the electric energy generated by the electric generator is converted to DC by the motor controller and then recovered to the power battery unit through high-voltage distribution for storage.

3. The asymmetric actuator electro-hydraulic control system according to claim 2, characterized in that: The electric generator includes a motor output working state and a motor power generation working state; when the electric generator is in the motor output working state, the electric generator drives the main pump motor and the volume compensation pump motor to be in pump mode; when the main pump motor and the volume compensation pump motor are in motor mode, the main pump motor and the volume compensation pump motor drive the electric generator to work in the motor power generation working state.

4. The asymmetric actuator electro-hydraulic control system according to claim 1, characterized in that: The electro-hydraulic reversing valve is a three-position, three-way solenoid reversing valve, including an upper working position, an initial position, and a lower working position. The control ports on both sides of the electro-hydraulic reversing valve are both connected to the control unit signal; when the electro-hydraulic reversing valve is in the upper working position, the oil inlet of the electro-hydraulic reversing valve is connected to the first working oil port of the electro-hydraulic reversing valve. At this time, the oil inlet of the electro-hydraulic reversing valve and the oil circuit between the A1 port of the main pump motor and the oil inlet of the holding valve are in a connected state; when the electro-hydraulic reversing valve is in the initial position, the oil inlet of the electro-hydraulic reversing valve and the first working oil port of the electro-hydraulic reversing valve and the second working oil port of the electro-hydraulic reversing valve are all in a cut-off state; when the electro-hydraulic reversing valve is in the lower working position, the oil inlet of the electro-hydraulic reversing valve is connected to the second working oil port of the electro-hydraulic reversing valve. At this time, the oil inlet of the electro-hydraulic reversing valve and the oil circuit between the B1 port of the main pump motor and the rod chamber N port of the asymmetric actuator are in a connected state.

5. The asymmetric actuator electro-hydraulic control system according to claim 1, characterized in that: A first pressure sensor is provided on the oil circuit between the A1 port of the main pump motor and the oil inlet of the holding valve, and a second pressure sensor is provided on the oil circuit between the B1 port of the main pump motor and the rod chamber N port of the asymmetric actuator. Both the first pressure sensor and the second pressure sensor are connected to the control unit signal.

6. The asymmetric actuator electro-hydraulic control system according to claim 1, characterized in that: The telescopic rod of the asymmetric actuator is connected to the load, and the telescopic action of the telescopic rod of the asymmetric actuator drives the load to extend and retract. A displacement sensor is provided at the load end, and the displacement sensor is connected to the control unit by signal.

7. The asymmetric actuator electro-hydraulic control system according to claim 6, characterized in that: The control unit includes a joystick, a button is provided directly above the joystick, the backward angle change of the joystick is linearly proportional to the load rising speed, and the drive motor works at the same time; the forward angle change of the joystick is linearly proportional to the load descending speed, and the drive motor works at the same time; the stroke of pressing the button directly above the joystick is linearly proportional to the swing angle of the control pump from 0 to the maximum negative swing angle, and the load is driven to fall without power; when the joystick is in a natural state without operation and resets to the middle position and the button reset does not operate, the electro-hydraulic reversing valve is in the initial position, and the oil circuit is in a cut-off state at this time; the three operations of the joystick forward, backward and button are independent of each other and there is no composite action, and the priority level is executed according to the first operation, that is, the first operation is not reset and the next operation instruction is not executed.

8. An electro-hydraulic control method for an asymmetric actuator, characterized in that: The asymmetric actuator electro-hydraulic control system applied to any one of the above claims 1-7 includes: a vertical working condition control method and a horizontal working condition control method, the vertical working condition control method includes control when the joystick of the operating handle is backward, control when the joystick of the operating handle is forward, and control when the joystick of the operating handle is reset to the state when the button is pressed, and the horizontal working condition control method includes control when the joystick of the operating handle is forward and control when the joystick of the operating handle is backward.

9. The electro-hydraulic control method for an asymmetric actuator according to claim 8, characterized in that: Under vertical working conditions, the control when the joystick of the operating handle is moved backward includes: starting the machine, self-checking the equipment status, moving the operating handle backward, and linearly increasing the pump swing angle from 0 to the maximum positive swing angle through the electro-hydraulic proportional control of the control unit. At the same time, after the control unit receives the state signal that the swing angle is greater than 0, it adjusts the motor controller to drive the motor, the electric generator is in the motor output working state, the main pump motor and the volume compensation pump motor are in pump mode, the electro-hydraulic reversing valve automatically switches to the lower working position, and the rodless cavity of the asymmetric actuator is controlled to be liquid-filled. The load increases, and when the load of the rodless cavity increases, the low-pressure oil discharged from the rod cavity of the asymmetric actuator flows through the pipeline to the B1 port of the main pump motor.

10. The electro-hydraulic control method for an asymmetric actuator according to claim 8, characterized in that: During vertical operation, the joystick's forward-moving control includes: startup, equipment status self-test, and the joystick's forward movement. The control unit's electro-hydraulic proportional control pump increases its swing angle linearly from 0 to its maximum negative angle. Simultaneously, upon receiving a signal indicating the swing angle is less than 0, the control unit controls the motor controller to drive the motor. The motor generator enters motor output mode, the main pump motor and the displacement compensation pump motor enter pump mode, and the electro-hydraulic reversing valve automatically switches to the upper position. The main pump motor controls high-pressure oil to flow from port B1 of the main pump motor and into the rod chamber at port N of the asymmetric actuator, reducing the load on the rod chamber. When the load on the rod chamber decreases, oil discharged from the rodless chamber of the asymmetric actuator flows through the holding valve to port A1 of the main pump motor. Due to the different cross-sectional areas of the two chambers in the asymmetric actuator, port B2 of the displacement compensation pump motor is connected to the oil circuit of the rodless chamber of the asymmetric actuator. Excess oil from the accumulator's auxiliary function enters port B2 of the displacement compensation pump motor and exits port A2 of the displacement compensation pump motor, returning to the tank.

11. The electro-hydraulic control method for an asymmetric actuator according to claim 8, characterized in that: Under vertical working conditions, the control when the button is pressed in the reset state of the joystick of the operating handle includes: power-on, equipment status self-check, the stroke of the button pressed directly above the handle is linearly proportional and symmetrical to the swing angle of the electro-hydraulic proportional control pump from 0 to the maximum negative swing angle, the load is dropped without power, the control unit controls the oil circuit inside the valve to remain connected, the electro-hydraulic reversing valve automatically switches to the lower working position, and feeds back the current status to the control unit. Through the control unit, the swing angle of the control pump increases linearly from 0 to the maximum negative swing angle with the stroke of pressing the button, the main pump motor and the volume compensation pump motor are in motor mode, and after the control unit receives the swing angle less than 0 status signal, the electric generator is in generator working state; The oil discharged from the rodless chamber of the asymmetric actuator flows to the A1 port of the main pump motor through the holding valve. The main pump motor outputs mechanical energy to drive the electric generator to generate electricity, thereby reducing the load of the rodless chamber outlet. When the load of the rodless chamber outlet decreases, part of the oil at the B1 port of the main pump motor enters the rod chamber of the asymmetric actuator. Due to the different cross-sectional areas of the two chambers of the asymmetric actuator, the oil circuit from the B2 port of the volume compensation pump motor to the B1 port of the main pump motor is connected, and the excess oil assisted by the accumulator enters through the B2 port of the volume compensation pump motor, exits from the A2 port of the volume compensation pump motor, and flows back to the oil tank.

12. The electro-hydraulic control method for an asymmetric actuator according to claim 8, characterized in that: Under horizontal working conditions, the control of the joystick of the operating handle when it is forward includes: starting the machine, self-checking the equipment status, the pump motor swing angle is in the positive swing angle state, at this time the joystick is reset, the control unit receives the reset signal, adjusts the motor controller, the electric generator is in the power generation working state, the main pump motor and the volume compensation pump motor are in motor mode, the electro-hydraulic reversing valve automatically switches to the upper working position, the control unit controls the oil circuit inside the valve to remain connected, the rod cavity of the asymmetric actuator is squeezed out of the liquid by the load inertia force, the electricity generated by the electric generator is rectified and inverted by the motor controller, and the electric energy is recovered to the power battery unit through high-voltage distribution. When the load is forward braking and the rod cavity discharges liquid, the oil at the A1 port of the main pump motor all enters the rodless cavity of the asymmetric actuator, and the accumulator auxiliary volume compensation pump motor compensates the oil from the oil tank to the rodless cavity of the asymmetric actuator.

13. The electro-hydraulic control method for an asymmetric actuator according to claim 8, characterized in that: Under horizontal working conditions, the control when the joystick of the operating handle is moved backward includes: starting the machine, self-checking the equipment status, the pump motor swing angle is in the negative swing angle state, the motor and pump are in energy output mode, at this time the joystick is reset, the control unit receives the reset signal, adjusts the motor controller, the electric generator is in the power generation working state, the main pump motor and the volume compensation pump motor are in motor mode, the electro-hydraulic reversing valve automatically switches to the lower position, the control unit controls the oil circuit inside the valve to remain connected, the rodless cavity of the asymmetric actuator is squeezed out by the inertia force of the load, the electricity generated by the electric generator is rectified and inverted by the motor controller, and the electrical energy is recovered to the power battery unit through high-voltage distribution. When the load reverses and the rodless cavity is braked, part of the oil at the B1 port of the main pump motor enters the rod cavity of the asymmetric actuator, and the excess oil assisted by the accumulator enters through the B2 port of the volume compensation pump motor and exits through the A2 port of the volume compensation pump motor and flows back to the oil tank.

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