A multi-mode compact direct-drive hydraulic winch system and control method

Abstract

The present invention discloses a multi-mode compact direct-drive hydraulic winch system and control method. A closed series pump-valve coordinated hydraulic system is designed to replace the open pump control or open valve control system of the traditional hydraulic winch, and the pump control and valve control modes can be switched. A low-speed, high-torque hydraulic motor is used to replace the high-speed axial hydraulic motor acceleration and deceleration device in the traditional hydraulic winch system. A pump-valve coordinated control method is proposed for the system, which divides a lifting task of the hydraulic winch into a pump-controlled rapid lifting link and a valve-controlled precise positioning link, and fully combines the advantages of pump-controlled volume speed regulation and valve-controlled throttling speed regulation. Compared with the traditional single pump control method, it has faster response and more accurate terminal positioning, and is more energy-efficient and has a shorter task duration than the traditional single valve control method. The pump-valve coordinated hydraulic winch system and control method proposed in the present invention provide a theoretical guidance for the new configuration design and intelligent control strategy research of high-performance compact hydraulic winches.

Description

Technical Field

[0001] The present invention belongs to the field of high-performance hydraulic winch system design and intelligent control strategy, and in particular relates to a multi-mode compact direct-drive hydraulic winch system and a control method. Background Art

[0002] As a typical electro-hydraulic servo control system, hydraulic winch has many advantages such as strong load capacity, high load stiffness, high power density, and high torque density. It is widely used in offshore equipment, mining machinery, construction machinery and other fields. The current rotary output method in the hydraulic winch system often adopts the configuration of high-speed axial hydraulic motor and reducer. With the development of low-speed and high-torque hydraulic motors, due to their advantages of high power density, high torque density and compact structure, they can be directly connected to high-power and high-torque actuators without the need for power matching through reducers. Compared with traditional high-speed hydraulic motor-reducer drives, they have a more compact transmission structure and more flexible configuration methods. Low-speed and high-torque hydraulic motors have obviously become a better solution for the output part of high-performance, high-power and compact hydraulic winches.

[0003] At the same time, the two basic circuits of the hydraulic winch system are the pump-controlled open circuit and the valve-controlled open circuit. The two circuits have their own advantages and are applied to different engineering machinery according to needs. The former is volumetric speed regulation, and the pump output flow is directly supplied to the hydraulic motor. Because there is no overflow and throttling loss, the system is efficient and energy-saving; the latter is throttling speed regulation, and the pump output flow is input into the hydraulic motor after throttling control by the proportional valve or servo valve. The electric proportional drive is adopted, and the system has a fast dynamic response. However, the two hydraulic circuits are used alone with a single structure, and it is often difficult to adapt to different application scenarios. In recent years, with the increase in high-power, high-torque, large inertia, fast response, and high-precision demand scenarios in the industry, higher requirements and greater challenges have been put forward for the design and servo control of hydraulic winch systems. Combining pump-controlled volumetric speed regulation with valve-controlled throttling speed regulation to propose a pump-valve coordinated speed regulation circuit can complement each other and will be an inevitable trend in the development of high-performance, high-power, compact hydraulic winch technology.

[0004] In summary, the present invention proposes a multi-mode compact direct-drive hydraulic winch system and control strategy. The winch system uses a low-speed, high-torque hydraulic motor to replace the configuration of a high-speed hydraulic motor acceleration and deceleration device, and a closed system to replace an open system, making the system configuration more compact. At the same time, it has the advantages of both the pump control system and the valve control system, and proposes a pump-valve coordinated control strategy to complete the lifting task. The present invention can be used to guide the design and control research of a new high-performance, high-power, compact hydraulic winch system. Summary of the invention

[0005] Aiming at the current demand for compact and high-performance new configuration design of hydraulic winch system, the present invention proposes a new configuration of hydraulic winch system driven directly by low-speed and high-torque hydraulic motor that can realize pump control and valve control mode switching. This configuration uses low-speed and high-torque hydraulic motor to replace the configuration of high-speed hydraulic motor acceleration and deceleration, and the closed system to replace the open system, making the system configuration more compact. Based on this system, a control strategy of pump-valve coordinated control is proposed for actual lifting operation tasks, which is more energy-efficient and more accurate in terminal positioning than the traditional single control loop.

[0006] The object of the present invention is achieved by the following technical solutions: a multi-mode compact direct-drive hydraulic winch system, the system comprising a main pump, a third non-return valve, an externally controlled differential pressure reducing valve, a three-position four-way proportional reversing valve and a low-speed high-torque hydraulic motor;

[0007] The main pump supplies oil to the low-speed high-torque hydraulic motor through an externally controlled differential pressure reducing valve and a three-position four-way proportional reversing valve, forming a pump-valve series oil circuit; a third one-way valve is connected in parallel at both ends of the externally controlled differential pressure reducing valve;

[0008] When pump control is adopted, the opening of the three-position four-way proportional reversing valve is adjusted to the maximum, and the oil of the main pump bypasses the externally controlled differential pressure reducing valve and is supplied to the low-speed high-torque hydraulic motor through the third one-way valve;

[0009] When valve control is adopted, the oil of the main pump is throttled through the externally controlled differential pressure reducing valve and the three-position four-way proportional reversing valve and flows into the low-speed and high-torque hydraulic motor.

[0010] Furthermore, the main pump is a closed variable displacement pump, which changes the direction of the oil by changing the inclination angle of the swash plate.

[0011] Furthermore, the external control oil hole of the externally controlled differential pressure reducing valve is connected to the low-speed and high-torque hydraulic motor via the second two-position two-way electromagnetic reversing valve, and the second two-position two-way electromagnetic reversing valve is controlled to perform pre-valve pressure compensation.

[0012] Furthermore, when in the valve control state, the valve port opening of the three-position four-way proportional reversing valve is adjusted to control the speed and angle of the low-speed and high-torque hydraulic motor.

[0013] Furthermore, the P port of the three-position four-way proportional reversing valve is connected to the oil outlet of the externally controlled differential pressure reducing valve, the T port is connected back to the main pump, and the A and B ports are respectively connected to the oil inlet and outlet of the low-speed and high-torque hydraulic motor to throttle and control the motor speed.

[0014] Furthermore, the system also has an oil replenishment pump rigidly connected to the main pump, and the oil replenishment pump is used to replenish oil to the low-speed and high-torque hydraulic motor.

[0015] Furthermore, the system also includes a brake, which is a pressure-loss type wet multi-disc brake, the oil inlet of which is connected to the oil replenishment pump and is opened by the back pressure of the oil replenishment circuit.

[0016] On the other hand, the present invention also provides a control method for a multi-mode compact direct-drive hydraulic winch system, the method comprising the following steps:

[0017] Step 1: Divide the lifting task of the hydraulic winch system into a pump-controlled rapid lifting stage, a valve-controlled precise positioning stage and a load holding stage; start the main pump and the oil replenishment pump, the oil replenishment pressure is greater than the brake opening pressure to release the brake, the three-position four-way proportional reversing valve is in the middle position, and the system is in the waiting stage;

[0018] Step 2: When the hydraulic winch system is in the pump-controlled rapid lifting stage, the three-position four-way proportional reversing valve is adjusted to have a maximum opening, and the rated flow is greater than the working flow; the swash plate angle of the main pump is adjusted so that the oil bypasses the differential pressure reducing valve through the third one-way valve to supply the low-speed high-torque hydraulic motor, thereby achieving rapid lifting of the terminal position;

[0019] Step 3: When the hydraulic winch system is lifted to the vicinity of the target position, the system switches to the valve-controlled precise positioning stage; at this time, the inclination angle of the main pump's swash plate is adjusted to cause the oil to change direction, and the oil flows into the low-speed, high-torque hydraulic motor through the differential pressure reducing valve and the three-position, four-way proportional reversing valve to ensure precise positioning at the end of the operation;

[0020] Step 4: After the system completes the lifting task, the main pump and the oil replenishment pump are turned off, the three-position four-way proportional reversing valve is adjusted to the middle position, the brake is closed, and the system is in the load holding stage.

[0021] Furthermore, when the system is in the pump control state, theoretically there is no throttling, the three-position four-way proportional reversing valve does not participate in the control, and the oil provided by the main pump and the oil replenishment pump all flows through the low-speed and high-torque hydraulic motor, and the speed and angle of the low-speed and high-torque hydraulic motor are controlled by the main pump.

[0022] Furthermore, when the system is in valve control state, the speed and angle of rotation of the low-speed, high-torque hydraulic motor are not directly controlled by the main pump, but the valve opening of the three-position, four-way proportional reversing valve is adjusted to control the speed and angle of rotation of the low-speed, high-torque hydraulic motor.

[0023] Beneficial effects of the present invention:

[0024] The present invention provides a multi-mode compact direct-drive hydraulic winch system and control strategy, which enables the winch system to switch between the pump-controlled volume speed regulation mode and the valve-controlled throttling speed regulation mode, while having the advantages and functions of both. At the same time, the low-speed, high-torque hydraulic motor is used to replace the configuration of the high-speed hydraulic motor acceleration and deceleration device, and the closed system replaces the open system, making the system configuration more compact. The proposed pump-valve coordinated control strategy divides the lifting operation task stage, and different stages correspond to different control methods. Compared with the traditional single control method, it has faster response, higher efficiency, and better terminal positioning.

[0025] The present invention has carried out an innovative system design for a high-performance, high-power, compact hydraulic system, and has unique advantages in particular in the compactness and new configuration of the winch system. BRIEF DESCRIPTION OF THE DRAWINGS

[0026] Figure 1 This is the schematic diagram of the pump-valve coordinated low-speed, high-torque direct-drive hydraulic winch system.

[0027] In the figure, 1 is an oil tank, 2 is a filter, 3 is a main pump, 4 is a servo motor, 5 is an oil replenishing pump, 6 is a first one-way valve, 7 is a second one-way valve, 8 is a first two-position two-way solenoid directional control valve, 9 is an accumulator, 10 is a third one-way valve, 11 is an externally controlled differential pressure reducing valve, 12 is a second two-position two-way solenoid directional control valve, 13 is a three-position four-way proportional directional control valve, 14 is a first relief valve, 15 is a second relief valve, 16 is a brake, and 17 is a low-speed high-torque hydraulic motor.

[0028] Figure 2 Schematic diagram of the pump control circuit of the system.

[0029] Figure 3 Schematic diagram of the valve control circuit of the system.

[0030] Figure 4 The control strategy block diagram of the system. DETAILED DESCRIPTION

[0031] The present invention is described in detail below with reference to the accompanying drawings and specific examples:

[0032] like Figure 1 As shown, the present invention provides a multi-mode compact direct-drive hydraulic winch system, and designs a closed series pump-valve coordinated hydraulic system to replace the open pump control or open valve control system of the traditional hydraulic winch. The system can switch between pump control and valve control modes, and has a higher degree of control freedom.

[0033] The pump-valve coordinated hydraulic winch system includes an oil tank 1, a filter 2, a main pump 3, a servo motor 4, an oil replenishment pump 5, a first one-way valve 6, a second one-way valve 7, a first two-position two-way electromagnetic reversing valve 8, an accumulator 9, a third one-way valve 10, an externally controlled differential pressure reducing valve 11, a second two-position two-way electromagnetic reversing valve 12, a three-position four-way proportional reversing valve 13, a first overflow valve 14, a second overflow valve 15, a brake 16 and a low-speed, high-torque hydraulic motor 17.

[0034] The main pump 3 is a closed variable pump, driven by a servo motor 4, to complete the closed loop oil supply; the replenishing oil pump 5 is rigidly connected to the main pump 3, the oil inlet is connected to the oil tank 1 through the filter 2, and the oil outlet is connected to two oppositely installed first check valves 6 and first check valves 7, which can prevent the oil from flowing back and complete the closed loop oil replenishment. The accumulator 9 is connected to the first check valve 6 and the first check valve 7 through a two-position two-way electromagnetic reversing valve 8, and participates in the system oil replenishment and eliminates pressure pulsation. The oil inlet end of the external control type differential pressure reducing valve 11 is connected to the main pump 3, and the oil outlet end is connected to the three-position four-way proportional reversing valve 13. Its external control oil hole is connected to the oil inlet of the low-speed high-torque hydraulic motor 17 through the second two-position two-way electromagnetic reversing valve 12. The second two-position two-way electromagnetic reversing valve 12 can be controlled to compensate the pre-valve pressure. The third check valve 10 is connected in parallel at both ends of the external control type differential pressure reducing valve 11, and passes through when the oil flows in the reverse direction to avoid throttling of the pressure reducing valve. The P port of the three-position four-way proportional reversing valve 13 is connected to the oil outlet of the externally controlled differential pressure reducing valve 11, the T port is connected back to the main pump 3, and the A and B ports are respectively connected to the oil inlet and outlet of the low-speed high-torque hydraulic motor 17, which can throttle and control the motor speed. The position function is M type. The first relief valve 14 and the second relief valve 15 are respectively connected in parallel to the oil inlet and outlet of the low-speed high-torque hydraulic motor 17 for circuit pressure protection. The brake 16 is a pressure-loss type wet multi-disc brake, and the oil inlet is connected to the oil replenishment pump 5, which can be opened by the back pressure of the oil replenishment circuit.

[0035] like Figure 2 As shown, the present invention provides a pump-valve coordinated low-speed, high-torque direct-drive hydraulic winch system, which has the function of a pump control system. The inclination angle of the swash plate of the main pump 3 is adjusted so that the oil bypasses the differential pressure reducing valve 11 through the third one-way valve 10, and the valve port of the three-position four-way proportional reversing valve 13 is the largest, and the system is theoretically not throttling.

[0036] like Figure 3 As shown, the present invention provides a pump-valve coordinated low-speed, high-torque direct-drive hydraulic winch system, which has the function of a valve control system, which adjusts the inclination angle of the main pump 3 swash plate to cause the oil to flow through the differential pressure reducing valve 11, and the second two-position two-way solenoid reversing valve 12 is opened to perform pressure compensation at the proportional valve port, and the three-position four-way proportional reversing valve 13 is throttled at the valve port.

[0037] like Figure 4As shown, the present invention provides a control method for a pump-valve coordinated multi-mode compact direct-drive hydraulic winch system, which divides the lifting task of the pump-valve coordinated low-speed and high-torque hydraulic winch system into a pump-controlled rapid lifting stage, a valve-controlled precise positioning stage and a load holding stage. The specific process is as follows:

[0038] Step 1: Start the servo motor 4, the main pump 3 and the oil replenishing pump 5. The oil replenishing pressure is greater than the opening pressure of the brake 16, so that the brake is released. The three-position four-way proportional reversing valve 13 is in the middle position, and the system is in the waiting stage.

[0039] Step 2: When the pump-valve coordinated hydraulic winch system is in the pump-controlled rapid lifting stage, adjust the three-position four-way proportional reversing valve 13 to the maximum valve opening, and the rated flow is greater than the working flow. Adjust the inclination angle of the swash plate of the main pump 3 so that the oil bypasses the differential pressure reducing valve 11 through the third one-way valve 10. The system is in the pump-controlled state, theoretically without throttling, and all the oil provided by the main pump 3 and the supplementary oil pump 5 flows through the low-speed high-torque hydraulic motor 17. When the system is in the state, the winch system has the fastest lifting speed, the highest efficiency, and the best energy-saving effect.

[0040] Step 3: When the pump-valve coordinated hydraulic winch system is lifted to the vicinity of the target position, the system switches to the valve-controlled precise positioning stage. At this time, the inclination angle of the swash plate of the main pump 3 is adjusted to cause the oil to change direction, and the oil flows into the low-speed high-torque hydraulic motor 17 through the differential pressure reducing valve 11 and the three-position four-way proportional reversing valve 13. When the system is in the above state, the valve opening of the three-position four-way proportional reversing valve 13 can be adjusted to control the speed and angle of the low-speed high-torque hydraulic motor 17 to ensure precise positioning at the end of the operation.

[0041] Step 4: When the system completes the lifting task, the servo motor 4, the main pump 3 and the replenishing pump 5 are turned off, the three-position four-way proportional reversing valve 13 is adjusted to the middle position, the brake 16 is closed, and the system is in the load holding stage.

[0042] When the hydraulic winch completes an operation task, it can perform a working cycle according to this process.

[0043] In summary, the present invention provides a multi-mode compact direct-drive hydraulic winch system and control method.

[0044] The above descriptions are merely embodiments of the present invention and are not intended to limit the patent scope of the present invention. Any equivalent structure or equivalent process transformation made using the contents of the present invention specification and drawings, or directly or indirectly applied in other related technical fields, are also included in the patent protection scope of the present invention.

Claims

1. A multi-mode compact direct-drive hydraulic winch system, characterized in that: The system comprises a main pump (3), a third non-return valve (10), an externally controlled differential pressure reducing valve (11), a three-position four-way proportional reversing valve (13), a brake (16) and a low-speed high-torque hydraulic motor (17); The main pump (3) supplies oil to a low-speed, high-torque hydraulic motor (17) via an externally controlled differential pressure reducing valve (11) and a three-position, four-way proportional reversing valve (13), forming a pump-valve series oil circuit, and changing the direction of the oil by changing the inclination angle of the swash plate of the main pump (3); a third non-return valve (10) is connected in parallel to both ends of the externally controlled differential pressure reducing valve (11); The brake (16) is a pressure-loss type wet multi-disc brake, the oil inlet of which is connected to the oil replenishment pump (5) and is opened by the back pressure of the oil replenishment circuit; When pump control is adopted, the valve port opening of the three-position four-way proportional reversing valve (13) is adjusted to the maximum, and the inclination angle of the swash plate of the main pump (3) is adjusted so that the oil of the main pump bypasses the externally controlled differential pressure reducing valve (11) and is supplied to the low-speed high-torque hydraulic motor (17) through the third non-return valve (10); When valve control is adopted, the inclination angle of the swash plate of the main pump (3) is adjusted to change the direction of the oil so that the oil of the main pump is throttled through the externally controlled differential pressure reducing valve (11) and the three-position four-way proportional reversing valve (13) and flows into the low-speed high-torque hydraulic motor (17). The valve opening of the three-position four-way proportional reversing valve (13) is adjusted to control the speed and angle of the low-speed high-torque hydraulic motor (17).

2. A multi-mode compact direct-drive hydraulic winch system according to claim 1, characterized in that: The external control oil hole of the externally controlled differential pressure reducing valve (11) is connected to a low-speed high-torque hydraulic motor (17) via a second two-position two-way electromagnetic reversing valve (12), and controls the second two-position two-way electromagnetic reversing valve (12) to perform pre-valve pressure compensation.

3. A multi-mode compact direct-drive hydraulic winch system according to claim 1, characterized in that: The P port of the three-position four-way proportional reversing valve (13) is connected to the oil outlet of the externally controlled differential pressure reducing valve (11), the T port is connected back to the main pump (3), and the A and B ports are respectively connected to the oil inlet and outlet of the low-speed high-torque hydraulic motor (17) to throttle and control the motor speed.

4. A multi-mode compact direct-drive hydraulic winch system according to claim 1, characterized in that: The system also has an oil replenishment pump (5) rigidly connected to the main pump (3), and the oil replenishment pump (5) is used to replenish oil to the low-speed high-torque hydraulic motor (17).

5. A control method for a multi-mode compact direct-drive hydraulic winch system according to any one of claims 1 to 4, characterized in that: The steps of this method are as follows: Step 1: Divide the lifting task of the hydraulic winch system into a pump-controlled rapid lifting stage, a valve-controlled precise positioning stage and a load holding stage; start the main pump (3) and the oil replenishment pump (5), the oil replenishment pressure is greater than the opening pressure of the brake (16), so that the brake is released, the three-position four-way proportional reversing valve (13) is in the middle position, and the system is in the waiting stage; Step 2: When the hydraulic winch system is in the pump-controlled rapid lifting stage, the three-position four-way proportional reversing valve (13) is adjusted to have a maximum valve opening, and the rated flow is greater than the working flow; the swash plate angle of the main pump (3) is adjusted so that the oil passes through the third one-way valve (10) and bypasses the differential pressure reducing valve (11) to supply the low-speed high-torque hydraulic motor (17), thereby achieving rapid lifting of the end position; Step 3: When the hydraulic winch system is lifted to the vicinity of the target position, the system switches to the valve-controlled precise positioning stage; at this time, the inclination angle of the swash plate of the main pump (3) is adjusted to cause the oil to change direction, and the oil flows into the low-speed high-torque hydraulic motor (17) through the differential pressure reducing valve (11) and the three-position four-way proportional reversing valve (13) to ensure precise positioning at the end of the operation; Step 4: When the system completes the lifting task, the main pump (3) and the oil replenishment pump (5) are turned off, the three-position four-way proportional reversing valve (13) is adjusted to the middle position, the brake (16) is turned off, and the system is in the load holding stage.

6. The control method of the multi-mode compact direct-drive hydraulic winch system according to claim 5, characterized in that: When the system is in a pump control state, the three-position four-way proportional reversing valve (13) does not participate in the control, and the oil provided by the main pump (3) and the supplementary oil pump (5) all flows through the low-speed high-torque hydraulic motor (17), and the speed and angle of the low-speed high-torque hydraulic motor (17) are controlled by the main pump (3).

7. The control method of the multi-mode compact direct-drive hydraulic winch system according to claim 5, characterized in that: When the system is in a valve-controlled state, the speed and rotation angle of the low-speed, high-torque hydraulic motor (17) are not directly controlled by the main pump (3), but the speed and rotation angle of the low-speed, high-torque hydraulic motor (17) are controlled by adjusting the valve opening of the three-position, four-way proportional reversing valve (13).

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