Control hydraulic system of winch

Abstract

The utility model provides a control hydraulic system of a winch, which comprises an oil tank, a pilot overflow valve, a first switch valve and a motor, a hydraulic pump is arranged on the oil tank and connected with a first port of the motor through an oil inlet pipeline, and a second port of the motor is connected with the oil tank through an oil return pipeline. A pilot-operated overflow valve is arranged between the oil inlet pipeline and the oil return pipeline, the oil inlet end of the pilot-operated overflow valve is connected with the oil inlet pipeline, and the oil outlet end of the pilot-operated overflow valve is connected with the oil return pipeline; a first switch valve is arranged on the oil return pipeline, a first port of the first switch valve is connected with a second port of the motor through the oil return pipeline, a second port of the first switch valve is connected with the oil tank through the oil return pipeline, and a first control end of the first switch valve is connected with the first port and the second port of the first switch valve. A second control end of the first switch valve is connected with the oil tank; by means of the structure, rapid rope releasing is achieved, and the structure of the crane can be protected against being snapped and damaged easily.

Description

Technical Field

[0001] The utility model relates to the technical field of winch control systems, and particularly relates to a control hydraulic system for a winch. Background Art

[0002] A winch is a light and small lifting device that lifts or pulls heavy objects by winding steel ropes or chains around a drum. Due to its simple operation and strong load-bearing capacity, winches are widely used in marine engineering, ships, coal mines, docks, mines, road and bridge projects, etc. In a marine environment, usually, a hydraulic control system is used to control the rotation of a hydraulic motor, and then the hydraulic motor drives the winch to operate, so as to complete the operations of winding and unwinding the rope and other operations related to the winch.

[0003] In a patent document with a Chinese patent application number of 202310244642.5 and a publication date of July 4, 2023, a winch hydraulic control system is disclosed, which includes a hydraulic oil tank, a hydraulic pump, and an electric motor. The inlet of the hydraulic pump is connected to the hydraulic oil tank, the electric motor is connected to the hydraulic pump, and the outlet of the hydraulic pump is connected to the P ports of the main directional valve group and the control valve group. The A and B ports of the main directional valve group are respectively connected to the A port of the first shuttle valve, the A port of the balance valve group, and the B port of the control valve group, the X port is connected to the B port of the second electromagnetic directional valve, the B and C ports of the first shuttle valve are respectively connected to the B port of the balance valve group and the B port of the second shuttle valve, the third pressure reducing valve is connected in parallel to the second solenoid valve, the P port of the second electromagnetic directional valve is connected to the X port of the control valve group, the A port of the second shuttle valve, and the SP port of the balance valve group, the C port of the second shuttle valve is connected to the rod chamber of the brake, the brake is connected to the hydraulic motor, and the outlet of the control valve group is connected to the inlet of the balance valve group. This design can maintain a constant tension of the steel rope and operate stably.

[0004] As the prior art of this document, its rope unwinding is achieved by first pumping hydraulic oil out of the oil tank, flowing through the motor, and then flowing back into the oil tank for circulation. In this way, the speed of rope unwinding is uniform. However, in this case, if the winch accidentally hooks an object heavier than the cargo (such as the hull) during hoisting on a ship, the torque of the winch will increase at this time. If it is not released in time, it is easy to cause the structure of the crane to be pulled and damaged. Therefore, when encountering such an emergency, rapid rope unwinding is required. Summary of the Invention

[0005] The utility model provides a control hydraulic system for a winch, which realizes rapid rope unwinding and enables the structure of the crane to be protected from being easily pulled and damaged.

[0006] To achieve the above object, the technical solution of the present utility model is: a control hydraulic system for a winch, including an oil tank, a pilot-operated relief valve, a first switching valve and a motor. A hydraulic pump is provided on the oil tank. The hydraulic pump is connected to the first port of the motor through an oil inlet pipeline. The second port of the motor is connected to the oil tank through an oil return pipeline. A pilot-operated relief valve is provided between the oil inlet pipeline and the oil return pipeline. The oil inlet end of the pilot-operated relief valve is connected to the oil inlet pipeline, and the oil outlet end of the pilot-operated relief valve is connected to the oil return pipeline. A first switching valve is provided on the oil return pipeline. The first port of the first switching valve is connected to the second port of the motor through the oil return pipeline. The second port of the first switching valve is connected to the oil tank through the oil return pipeline. The first control end of the first switching valve is connected to the first port and the second port of the first switching valve. The second control end of the first switching valve is connected to the oil tank. The first control end of the first switching valve controls the first port and the second port of the first switching valve to be connected. The second control end of the first switching valve controls the first port and the second port of the first switching valve to be disconnected.

[0007] In the above structure, when taking in the rope, the oil tank outputs hydraulic oil into the oil inlet pipeline, then passes through the motor and enters the oil tank through the oil return pipeline to realize the operation of taking in the rope. At the same time, a first switching valve is provided on the oil return pipeline. When the motor rotates normally, the oil tank transports hydraulic oil to the motor through the oil inlet pipeline and flows through the motor into the oil return pipeline. The hydraulic oil in the oil return pipeline flows to the first control end of the first switching valve, thereby driving the first switching valve to change direction and connect the first port and the second port. As a result, the oil return pipeline is connected to the oil tank, and the hydraulic oil can flow back to the oil tank to realize circulation. When an incorrect operation of lifting a heavy object occurs, at this time, it is in the state of taking in the rope. The oil tank feeds oil into the second control end of the first switching valve, driving the first switching valve to change direction and control the first port and the second port to be disconnected. As a result, the hydraulic oil cannot flow back to the oil tank from the oil return pipeline but flows to the second port of the motor. Since the oil pressure in the oil inlet pipeline is greater than the adjusted pressure of the pilot-operated relief valve, the pilot oil circuit of the pilot-operated relief valve is conducted to relieve pressure to the oil return pipeline, thereby increasing the oil pressure on the oil return pipeline and making the oil pressure at the end of the motor connected to the oil return pipeline greater than the oil pressure at the end of the motor connected to the oil inlet pipeline. And due to the overflow function of the pilot-operated relief valve, a circulating circuit is formed between the oil inlet pipeline, the oil return pipeline and the motor through the pilot-operated relief valve. The oil tank continues to output hydraulic oil to the oil inlet pipeline, thereby increasing the hydraulic oil in the circulating circuit, increasing the pressure difference between the two ends of the motor, and then increasing the rotation speed of the motor to realize rapid rope release.

[0008] Further, a second switching valve is provided between the oil inlet end of the pilot-operated relief valve and the oil inlet pipeline. The first port of the second switching valve is connected to the oil inlet pipeline, and the second port of the second switching valve is connected to the oil inlet end of the pilot-operated relief valve.

[0009] With the above settings, by setting the second switching valve, the oil circuit between the inlet oil pipeline and the pilot-operated overflow valve is opened only when the pilot-operated overflow valve needs to be used, thus facilitating the control of the hydraulic system.

[0010] Furthermore, a balance valve group is provided on the inlet oil pipeline. The balance valve group includes a balance overflow valve and a balance check valve. The inlet end of the balance overflow valve is connected to the first port of the motor through the inlet oil pipeline, and the outlet end of the balance overflow valve is connected to the hydraulic pump through the inlet oil pipeline. The inlet end of the balance check valve is connected to the outlet end of the balance overflow valve, and the outlet end of the balance check valve is connected to the inlet end of the balance overflow valve.

[0011] With the above settings, by setting the balance valve group, the hydraulic oil output of the inlet oil pipeline is made stable.

[0012] Furthermore, a brake valve is also provided on the motor. The control end of the brake valve is connected to the inlet oil pipeline and the outlet oil pipeline through a brake reversing valve. The P port of the brake reversing valve is connected to the oil tank, the A port of the brake reversing valve is connected to the control end of the brake valve, and the control end of the brake reversing valve is connected to the inlet oil pipeline and the outlet oil pipeline.

[0013] With the above settings, by connecting the control end of the brake valve reversing valve to the inlet oil pipeline and the outlet oil pipeline, when starting the winch, the hydraulic oil in the inlet oil pipeline and the outlet oil pipeline flows to the control end of the brake reversing valve and controls the brake reversing valve to reverse so that the A port communicates with the P port, thereby enabling the hydraulic oil output from the oil tank to flow to the control end of the brake valve, thus driving the brake valve to open and facilitating the rotation of the motor.

[0014] Furthermore, a spring is also provided on the second control end of the first switching valve. The pressure of the hydraulic oil at the second control end plus the pressure of the spring is greater than the pressure of the hydraulic oil at the first control end of the first switching valve.

[0015] With the above settings, by setting the spring, when closing the first switching valve, the hydraulic oil pressure flowing from the oil tank into the second control end of the first switching valve plus the elastic force of the spring overcomes the hydraulic oil pressure at the first control end of the first switching valve, thereby driving the first switching valve to close, so that the hydraulic oil cannot flow back to the oil tank through the return oil pipeline. Brief Description of the Drawings

[0016] Figure 1 is a schematic diagram of the hydraulic system of the present utility model.

[0017] Figure 2 is Figure 1 an enlarged view of part A in Detailed Description of the Preferred Embodiments

[0018] The present utility model will be further described in detail below with reference to the drawings and specific embodiments.

[0019] AsFigure 1 - Figure 2 As shown in the figure, a control hydraulic system for a winch includes an oil tank 1, a pilot-operated relief valve 2, a first switching valve 3, and a motor 4. A hydraulic pump (not shown in the figure) is provided on the oil tank 1. The hydraulic pump is connected to the first port 41 of the motor 4 through an oil inlet pipeline 11. The second port 42 of the motor 4 is connected to the oil tank 1 through an oil return pipeline 12. A pilot-operated relief valve 2 is provided between the oil inlet pipeline 11 and the oil return pipeline 12. The oil inlet end of the pilot-operated relief valve 2 is connected to the oil inlet pipeline 11, and the oil outlet end of the pilot-operated relief valve 2 is connected to the oil return pipeline 12. A first switching valve 3 is provided on the oil return pipeline 12. The first port of the first switching valve 3 is connected to the second port 42 of the motor 4 through the oil return pipeline 12. The second port of the first switching valve 3 is connected to the oil tank 1 through the oil return pipeline 12. The first control end 31 of the first switching valve 3 is connected to the first port and the second port of the first switching valve 3. The second control end 32 of the first switching valve 3 is connected to the oil tank. The first control end 31 of the first switching valve 3 controls the connection between the first port and the second port of the first switching valve 3, and the second control end 32 of the first switching valve 3 controls the disconnection between the first port and the second port of the first switching valve 3.

[0020] A second switching valve 21 is provided between the oil inlet end of the pilot-operated relief valve 2 and the oil inlet pipeline. The first port of the second switching valve 21 is connected to the oil inlet pipeline 11, and the second port of the second switching valve 21 is connected to the oil inlet end of the pilot-operated relief valve 2. By providing the second switching valve 21, the oil circuit between the oil inlet pipeline 11 and the pilot-operated relief valve 2 is opened only when the pilot-operated relief valve 2 needs to be used, thus facilitating the control of the hydraulic system.

[0021] A balance valve group 5 is provided on the oil inlet pipeline 11. The balance valve group 5 includes a balance relief valve 51 and a balance check valve 52. The oil inlet end of the balance relief valve 51 is connected to the first port 41 of the motor 4 through the oil inlet pipeline 11. The oil outlet end of the balance relief valve 51 is connected to the hydraulic pump through the oil inlet pipeline 11. The oil inlet end of the balance check valve 52 is connected to the oil outlet end of the balance relief valve 51, and the oil outlet end of the balance check valve 52 is connected to the oil inlet end of the balance relief valve 51. By providing the balance valve group 5, the hydraulic oil output of the oil inlet pipeline 11 is made stable.

[0022] As Figure 1 ​As shown, a brake valve 43 is further provided on the motor 4. The control end of the brake valve 43 is connected to the oil inlet pipe and the oil outlet pipe through a brake reversing valve 44. The P end of the brake reversing valve 44 is connected to the fuel tank. The A end of the brake reversing valve is connected to the control end of the brake valve. The control end K of the brake reversing valve 44 is connected to the oil inlet pipe 11 and the oil outlet pipe 12. By connecting the control end K of the brake valve reversing valve 44 to the oil inlet pipe 11 and the oil outlet pipe 12, when starting the winch, the hydraulic oil in the oil inlet pipe 11 and the oil outlet pipe 12 flows to the control end of the brake reversing valve 44 and controls the brake reversing valve 44 to reverse so that the A end communicates with the P end, so that the hydraulic oil output from the fuel tank 1 flows to the control end of the brake valve 43, thereby driving the brake valve 43 to open, facilitating the rotation of the motor 4.

[0023] As Figure 2 As shown, a spring 33 is further provided on the second control end 32 of the first switching valve 3. The pressure of the hydraulic oil at the second control end 32 plus the pressure of the spring 33 is greater than the pressure of the hydraulic oil at the first control end 31 of the first switching valve 3. By providing the spring 33, when closing the first switching valve 3, the hydraulic oil pressure in the second control end 32 of the first switching valve 3 flowing from the fuel tank 1 plus the elastic force of the spring 33 overcomes the hydraulic oil pressure at the first control end 31 of the first switching valve 3, thereby driving the first switching valve 3 to close, so that the hydraulic oil cannot flow back to the fuel tank through the oil return pipe 12.

[0024] In this embodiment, an electromagnetic reversing valve (not shown in the figure) is provided between the second control end of the first switching valve and the fuel tank. When the electromagnetic reversing valve reverses, the oil circuit between the first switching valve and the second control end is communicated, and the fuel tank outputs hydraulic oil to the second control end of the first switching valve.

[0025] Working principle of the utility model: When taking in the rope, the oil tank 1 outputs hydraulic oil, which enters the oil inlet pipeline 11 through the balanced check valve 52, then passes through the motor 4 and enters the oil tank 1 through the oil return pipeline 12 to realize the rope-taking-in operation. At the same time, a first switching valve 3 is provided on the oil return pipeline 12. When the motor 4 rotates normally, the oil tank 1 transports hydraulic oil to the motor 4 through the oil inlet pipeline 11 and flows into the oil return pipeline 12 through the motor 4. The hydraulic oil in the oil return pipeline 12 flows to the first control end 31 of the first switching valve 3, thereby driving the first switching valve 3 to change its direction and connect the first port and the second port. As a result, the oil return pipeline 12 is connected to the oil tank, and the hydraulic oil can flow back to the oil tank 1 to realize circulation. When an error occurs in lifting a heavy object during the rope-taking-in state, the oil tank 1 supplies oil to the second control end 32 of the first switching valve 3, driving the first switching valve 3 to change its direction and control the disconnection of the first port and the second port. As a result, the hydraulic oil cannot flow back to the oil tank 1 from the oil return pipeline 12 but flows to the second port 42 of the motor 4; since the oil pressure in the oil inlet pipeline 11 is greater than the regulating pressure of the pilot-operated relief valve, the pilot oil circuit of the pilot-operated relief valve 2 is conducted to relieve pressure to the oil return pipeline 12, thereby increasing the oil pressure on the oil return pipeline 12 and making the oil pressure at the end of the motor 4 connected to the oil return pipeline 12 greater than the oil pressure at the end of the motor connected to the oil inlet pipeline 11. And due to the overflow effect of the pilot-operated relief valve 2, a circulating circuit is formed among the oil inlet pipeline, the oil return pipeline and the motor through the pilot-operated relief valve. The oil tank continues to output hydraulic oil to the oil inlet pipeline, thereby increasing the hydraulic oil in the circulating circuit continuously, increasing the pressure difference between the two ends of the motor 4, and then increasing the rotational speed of the motor 4 to realize rapid rope release.

Claims

1. A winch control hydraulic system, characterized in that: It includes an oil tank, a pilot relief valve, a first switch valve and a motor, a hydraulic pump is arranged on the oil tank, the hydraulic pump is connected to the first port of the motor through an oil inlet pipeline, the second port of the motor is connected to the oil tank through an oil return pipeline, a pilot relief valve is arranged between the oil inlet pipeline and the oil return pipeline, the oil inlet end of the pilot relief valve is connected to the oil inlet pipeline, and the oil outlet end of the pilot relief valve is connected to the oil return pipeline; a first switch valve is arranged on the oil return pipeline, the first port of the first switch valve is connected to the second port of the motor through the oil return pipeline, the second port of the first switch valve is connected to the oil tank through the oil return pipeline, the first control end of the first switch valve is connected to the first port and the second port of the first switch valve, the second control end of the first switch valve is connected to the oil tank, the first control end of the first switch valve controls the first port and the second port of the first switch valve to be connected, and the second control end of the first switch valve controls the first port and the second port of the first switch valve to be disconnected.

2. A winch control hydraulic system according to claim 1, characterized in that: A second switch valve is provided between the oil inlet end of the pilot relief valve and the oil inlet pipeline, a first port of the second switch valve is connected to the oil inlet pipeline, and a second port of the second switch valve is connected to the oil inlet end of the pilot relief valve.

3. A winch control hydraulic system according to claim 1, characterized in that: A balancing valve group is provided on the oil inlet pipeline, and the balancing valve group includes a balancing overflow valve and a balancing check valve. The oil inlet end of the balancing overflow valve is connected to the first port of the motor through the oil inlet pipeline, and the oil outlet end of the balancing overflow valve is connected to the hydraulic pump through the oil inlet pipeline. The oil inlet end of the balancing check valve is connected to the oil outlet end of the balancing overflow valve, and the oil outlet end of the balancing check valve is connected to the oil inlet end of the balancing overflow valve.

4. A winch control hydraulic system according to claim 1, characterized in that: A brake valve is also provided on the motor, and the control end of the brake valve is connected to the oil inlet pipeline and the oil outlet pipeline through the brake reversing valve. The P end of the brake reversing valve is connected to the oil tank, and the A end of the brake reversing valve is connected to the control end of the brake valve. The control end of the brake reversing valve is connected to the oil inlet pipeline and the oil outlet pipeline.

5. The winch control hydraulic system according to claim 1, characterized in that: A spring is also provided on the second control end of the first switch valve, and the hydraulic oil pressure at the second control end plus the pressure of the spring is greater than the hydraulic oil pressure at the first control end of the first switch valve.

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