Overload protection system of winch

Abstract

The overload protection system comprises an oil tank, a pilot overflow valve, a first switch valve, a motor and a first control valve bank, 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; the first control valve group comprises a first control switch valve, a first control reversing valve and a first control overflow valve; by means of the structure, under the emergency condition, the adjusting pressure of the overflow valve can be adjusted and relieved, and therefore the winch is controlled to quickly loosen the steel wire rope to achieve emergency rope abandoning.

Description

Technical Field

[0001] The invention relates to the technical field of winch control systems, and in particular to an overload protection system for a winch. Background Art

[0002] A winch, also known as a winch, is a common mechanical device. The winch winds a wire rope or chain around a drum, and the wire rope is retracted and released by the rotation of the drum to lift or pull an object. Hydraulic winches are widely used in marine engineering, construction, water conservancy projects, mining and other operating fields. They are important auxiliary tools for completing the retraction, lifting, and flat towing of equipment and materials. With the increase in the rated working conditions of lifting machinery and the complexity of the working environment, the safety, stability and controllability of hydraulic winches are increasingly required.

[0003] A patent document with Chinese patent application number 202323007055.9 and publication date 2024.07.02 discloses a hydraulic system for winch cable storage, including a storage winch motor, an oil tank and a pilot overflow valve, the oil tank is provided with a first opening and a second opening, one end of the storage winch motor is connected to the first opening of the oil tank through a first oil circuit, and the other end of the storage winch motor is connected to the second opening of the oil tank through a second oil circuit, and a pilot overflow valve is provided between the first oil circuit and the second oil circuit, the oil inlet end of the pilot overflow valve is connected to the first oil circuit, the oil outlet end of the pilot overflow valve is connected to the second oil circuit, and the control end of the pilot overflow valve is also connected to the first oil circuit; the hydraulic system of the above document enables the storage winch to control the rotation of the winch motor to be stable when the rope is being stored, so that the cable maintains a constant tension state.

[0004] As in the prior art of the document, if a lifting operation is carried out on a platform with a supply ship, and the hook connected to the wire rope is accidentally hooked on the supply ship and cannot be removed, the supply ship is located at sea and will move with the wind and waves due to wind and waves. If the wire rope on the winch is not released quickly, the winch will be pulled down by the supply ship and cause an accident. If the rope is released by simply releasing the pressure through the pressure relief valve, when the regulating pressure of the pressure relief valve is at a high level, the pressure must be released when the regulating pressure of the pressure relief valve is reached, thereby failing to ensure rapid rope release. Summary of the invention

[0005] The invention provides an overload protection system for a winch, which can adjust the regulating pressure of a relief valve and release the regulating pressure of the relief valve in an emergency, thereby controlling the winch to quickly release a steel wire rope to realize emergency rope abandonment.

[0006] To achieve the above-mentioned purpose, the technical scheme of the present invention is: an overload protection system for a winch, comprising an oil tank, a pilot relief valve, a first switch valve, a first control valve group 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 relief valve is provided 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 provided on the oil return pipeline, the first control valve group comprises a first control switch valve, a first control reversing valve and a first control relief valve, the P end and the T end of the first control reversing valve are connected to the oil tank, the A end of the first control reversing valve is connected to the control end of the first control switch valve, the first port of the first control switch valve is connected to the oil tank through the first control relief valve, the second port of the first control switch valve is connected to the control oil circuit of the pilot relief valve, and the relief pressure of the first control relief valve is less than the control pressure of the control oil circuit of the pilot relief valve; The second control end of the first switch valve is connected to the A end of the first switch valve through the first shuttle valve, the first port of the first switch valve is connected to the second port of the motor through the return oil pipeline, the second port of the first switch valve is connected to the oil tank through the return oil pipeline, the first control end of the first switch valve connects 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.

[0007] In the above structure, when the rope is reeled in, the oil tank outputs hydraulic oil into the oil inlet pipe and then passes through the motor and the return oil pipe and enters the oil tank for circulation to realize the rope reeling operation. At the same time, a first switch valve is provided on the return oil pipe. When the motor rotates normally, the oil tank delivers hydraulic oil to the motor through the oil inlet pipe and flows into the return oil pipe through the motor. The hydraulic oil in the return oil pipe flows to the first control end of the first switch valve, thereby driving the first switch valve to switch and connect the first port and the second port, thereby making the return oil pipe connected with the oil tank, and the hydraulic oil can flow back to the oil tank to realize circulation. When the heavy object is lifted by erroneous operation, it is in the rope reeling state at this time, and the first control reversing valve is manually turned on. The first control reversing valve is switched to connect the A end with the P end. The oil tank outputs hydraulic oil to the control end of the first control switch valve through the first control reversing valve, so that the first control switch valve is switched and connects the first port and the second port of the first control switch valve, thereby making the control hydraulic oil of the control oil circuit of the pilot-operated relief valve discharge through the first control relief valve After derrick is driven by derrick of derrick shaft, the derrick of derrick of derrick shaft is turned on, and derrick of derrick shaft is turned on.

[0008] Furthermore, 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.

[0009] The above arrangement, by providing the second switch valve, allows the oil circuit between the oil inlet pipeline and the pilot-operated relief valve to be opened only when the pilot-operated relief valve is needed, thereby facilitating control of the hydraulic system.

[0010] Furthermore, 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.

[0011] The above arrangement, by setting a balancing valve group, makes the hydraulic oil output of the oil inlet pipeline stable.

[0012] Furthermore, a brake valve is 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, the A end 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 oil inlet pipeline and the oil outlet pipeline.

[0013] The above arrangement connects the oil inlet pipeline and the oil outlet pipeline through the control end of the brake valve reversing valve. When the winch is to be started, the hydraulic oil in the oil inlet pipeline and the oil outlet pipeline flows to the control end of the brake reversing valve and controls the reversal of the brake reversing valve so that the A end is connected to the P end, so that the hydraulic oil output by the oil tank flows to the control end of the brake valve, thereby driving the brake valve to open, facilitating the rotation of the motor.

[0014] Furthermore, a spring is 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.

[0015] The above arrangement, by setting a spring, ensures that when the first switch valve is to be closed, the hydraulic oil pressure flowing from the oil tank to the second control end of the first switch valve plus the elastic force of the spring overcomes the hydraulic oil pressure at the first control end of the first switch valve, thereby driving the first switch valve to close, so that the hydraulic oil cannot flow back to the oil tank through the return oil pipe.

[0016] Furthermore, a first shuttle valve is provided between the second control end of the first switch valve and the A end of the first control reversing valve, the first port of the first shuttle valve is connected to the A end of the first control reversing valve, the second port of the first shuttle valve is connected to the oil tank, and the third port of the first shuttle valve is connected to the second control end of the first switch valve.

[0017] In the above arrangement, by arranging the first shuttle valve between the second control end of the first switch valve and the A end of the first control reversing valve, the hydraulic oil flowing to the second control end of the first switch valve through the first control reversing valve and the hydraulic oil flowing from the oil tank to the second control end of the first switch valve will not conflict with each other. BRIEF DESCRIPTION OF THE DRAWINGS

[0018] Figure 1 It is a schematic diagram of the hydraulic system of the present invention.

[0019] Figure 2 for Figure 1 Enlarged view of point A in the middle.

[0020] Figure 3 for Figure 1 Enlarged view of point B in the middle. DETAILED DESCRIPTION

[0021] The present invention is further described in detail below with reference to the accompanying drawings and specific embodiments.

[0022] like Figure 1-Figure 3 As shown, an overload protection system for a winch comprises an oil tank 1, a pilot relief valve 2, a first switch valve 3, a motor 4 and a first control valve group. A hydraulic pump (not shown in the figure) is arranged on the oil tank 1. The hydraulic pump is connected to a first port 41 of the motor 4 through an oil inlet pipeline 11. A second port 42 of the motor 4 is connected to the oil tank 1 through an oil return pipeline 12. A pilot relief valve 2 is arranged between the oil inlet pipeline 11 and the oil return pipeline 12. The oil inlet end of the pilot relief valve 2 is connected to the oil inlet pipeline 11, and the oil outlet end of the pilot relief valve 2 is connected to the oil return pipeline 12. A first switch valve 3 is provided on it, a first port of the first switch valve 3 is connected to the second port 42 of the motor 4 through the return oil pipeline 12, the second port of the first switch valve 3 is connected to the oil tank 1 through the return oil pipeline 12, a first control end 31 of the first switch valve 3 is connected to the first port and the second port of the first switch valve 3, the second control end 32 of the first switch valve 3 is connected to the oil tank, the first control end 31 of the first switch valve 3 controls the first port and the second port of the first switch valve 3 to be connected, and the second control end 32 of the first switch valve 3 controls the first port and the second port of the first switch valve 3 to be disconnected.

[0023] The first control valve group includes a first control switch valve 81, a first control reversing valve 82 and a first control overflow valve 83. The P end and T end of the first control reversing valve 82 are connected to the oil tank 1, the A end of the first control reversing valve 82 is connected to the control end 811 of the first control switch valve 81, the first port of the first control switch valve 81 is connected to the oil tank 1 through the first control overflow valve 83, and the second port of the first control switch valve 81 is connected to the control oil circuit 20 of the pilot overflow valve 2. The overflow pressure of the first control overflow valve 83 is less than the control pressure of the control oil circuit 20 of the pilot overflow valve 2.

[0024] In this embodiment, the control end 821 of the first control reversing valve is connected to a control button (not shown in the figure) in the crane cab through an external circuit. When an emergency occurs, the staff in the cab presses the control button to drive the first control reversing valve to achieve reversing.

[0025] A first shuttle valve 84 is provided between the second control end 32 of the first switch valve 3 and the A end of the first control reversing valve 82, the first port 841 of the first shuttle valve 84 is connected to the A end of the first control reversing valve 82, the second port 842 of the first shuttle valve 84 is connected to the oil tank 1, and the third port 843 of the first shuttle valve 84 is connected to the second control end 32 of the first switch valve 3.

[0026] The first shuttle valve 84 is arranged between the second control end 32 of the first switch valve 3 and the A end of the first control reversing valve 82. When the rope is collected in the normal state, the hydraulic oil of the control oil tank 1 enters the second port 842 of the first shuttle valve 84, and the first port 841 of the first shuttle valve 84 cannot supply oil because the first control switch valve 82 is in the closed state, so the hydraulic oil in the oil tank 1 enters the second control end 32 of the first switch valve 3 through the second port 842, so that the first switch valve 3 is closed, so that the rope collection operation can be closed when the rope is collected. When emergency rope collection is required, since the first control switch valve 82 is in the conducting state, the hydraulic oil of the oil tank 1 enters the first port 841 of the first shuttle valve 84 through the first control switch valve 82 and then flows into the control end of the first switch valve 3, so that the first switch valve 3 is closed, so that the emergency rope collection is realized. And the hydraulic oil flowing to the second control end 32 of the first switch valve 3 through the first control reversing valve 82 and the hydraulic oil flowing to the second control end 32 of the first switch valve 3 from the oil tank 1 will not conflict with each other.

[0027] A second switch valve 21 is provided between the oil inlet end of the pilot relief valve 2 and the oil inlet pipeline, wherein a first port of the second switch valve 21 is connected to the oil inlet pipeline 11, and a second port of the second switch valve 21 is connected to the oil inlet end of the pilot relief valve 2. By providing the second switch valve 21, the oil circuit between the oil inlet pipeline 11 and the pilot relief valve 2 is opened only when the pilot relief valve 2 is needed, thereby facilitating control of the hydraulic system.

[0028] A balancing valve group 5 is provided on the oil inlet pipeline 11, and the balancing valve group 5 includes a balancing relief valve 51 and a balancing check valve 52. The oil inlet end of the balancing relief valve 51 is connected to the first port 41 of the motor 4 through the oil inlet pipeline 11, and the oil outlet end of the balancing relief valve 51 is connected to the hydraulic pump through the oil inlet pipeline 11. The oil inlet end of the balancing check valve 52 is connected to the oil outlet end of the balancing relief valve 51, and the oil outlet end of the balancing check valve 52 is connected to the oil inlet end of the balancing relief valve 51. By providing the balancing valve group 5, the hydraulic oil output of the oil inlet pipeline 11 is stable.

[0029] like Figure 1As shown, a brake valve 43 is also provided on the motor 4, and the control end of the brake valve 43 is connected to the oil inlet pipeline and the oil outlet pipeline through a brake reversing valve 44, the P end of the brake reversing valve 44 is connected to the oil tank, the A end of the brake reversing valve is connected to the control end of the brake valve, and the control end K of the brake reversing valve 44 is connected to the oil inlet pipeline 11 and the oil outlet pipeline 12. The control end K of the brake valve reversing valve 44 is connected to the oil inlet pipeline 11 and the oil outlet pipeline 12. When the winch is to be started, the hydraulic oil in the oil inlet pipeline 11 and the oil outlet pipeline 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 is connected to the P end, so that the oil tank 1 outputs the hydraulic oil to flow to the control end of the brake valve 43, thereby driving the brake valve 43 to open, so that the motor 4 rotates.

[0030] like Figure 2 As shown, a spring 33 is further provided on the second control end 32 of the first switch valve 3, and the hydraulic oil pressure at the second control end 32 plus the pressure of the spring 33 is greater than the hydraulic oil pressure at the first control end 31 of the first switch valve 3. By providing the spring 33, when the first switch valve 3 is to be closed, the hydraulic oil pressure flowing from the oil tank 1 to the second control end 32 of the first switch valve 3 plus the elastic force of the spring 33 overcomes the hydraulic oil pressure at the first control end 31 of the first switch valve 3, thereby driving the first switch valve 3 to close, so that the hydraulic oil cannot flow back to the oil tank through the return oil pipeline 12.

[0031] The working principle of the present invention is as follows: when the rope is being collected, the hydraulic oil output from the oil tank 1 enters the oil inlet pipe 11 through the balanced one-way valve 52, then passes through the motor 4 and enters the oil tank 1 through the oil return pipe 12 to circulate and realize the rope collection operation. At the same time, a first switch valve 3 is arranged on the oil return pipe 12. When the motor 4 rotates normally, the oil tank 1 delivers the hydraulic oil to the motor 4 through the oil inlet pipe 11 and flows into the oil return pipe 12 through the motor 4. The hydraulic oil in the oil return pipe 12 flows to the first control end 31 of the first switch valve 3, thereby driving the first switch valve 3 to switch and connect the first switch valve 3. A port and a second port are connected, thereby connecting the return oil pipeline 12 with the oil tank, and the hydraulic oil can flow back to the oil tank 1 to realize circulation. When the weight is hoisted by mistake, it is in the rope-collecting state at this time, and the first control reversing valve is manually turned on, and the first control reversing valve 82 is switched to connect the A end with the P end. The oil tank outputs the hydraulic oil to the control end 811 of the first control switch valve 81 through the first control reversing valve 82, so that the first control switch valve 81 is switched and connected to the first port and the second port of the first control switch valve 81, thereby making the control oil circuit 22 of the pilot relief valve 2 0 is depressurized through the first control relief valve 83 and flows back to the oil tank, thereby reducing the regulating pressure of the pilot relief valve 2. Since the oil pressure in the oil inlet pipeline 11 is greater than the regulating pressure of the pilot relief valve 2, the pilot relief valve 2 is driven to open, thereby causing the hydraulic oil in the oil inlet pipeline 11 to be depressurized through the pilot relief valve 2 to the return oil pipeline 12, thereby increasing the oil pressure on the return oil pipeline 12, and making the oil pressure at the end of the motor 4 connected to the return oil pipeline 12 greater than the oil pressure at the end of the motor connected to the oil inlet pipeline 11, and due to the pilot relief valve The overflow effect of 2 forms a circulation loop between the oil inlet pipeline, the oil return pipeline and the motor through the pilot overflow valve, and the oil tank continues to output hydraulic oil to the oil inlet pipeline, thereby increasing the hydraulic oil in the circulation loop, thereby increasing the pressure difference at both ends of the motor 4, and then increasing the speed of the motor 4 to achieve rapid rope release, so that when rapid rope release is required, it is only necessary to manually press the first control reversing valve to switch the direction, and the first switch valve can be controlled to open and the pilot overflow valve can be controlled to release the pressure at the same time, so that the internal circulation oil circuit can be quickly formed to ensure rapid rope release.

Claims

1. A winch overload protection system, characterized in that: It includes an oil tank, a pilot relief valve, a first switch valve, a first control valve group and a motor. A hydraulic pump is provided on the oil tank. The hydraulic pump is connected to a 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 provided 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 provided on the oil return pipeline. The first control valve group includes a first control switch valve, a first control reversing valve and a first control relief valve, the P end and the T end of the first control reversing valve are connected to the oil tank, the A end of the first control reversing valve is connected to the control end of the first control switch valve, the first port of the first control switch valve is connected to the oil tank through the first control relief valve, the second port of the first control switch valve is connected to the control oil circuit of the pilot relief valve, and the relief pressure of the first control relief valve is less than the control pressure of the control oil circuit of the pilot relief valve; The second control end of the first switch valve is connected to the A end of the first switch valve through the first shuttle valve, the first port of the first switch valve is connected to the second port of the motor through the return oil pipeline, the second port of the first switch valve is connected to the oil tank through the return oil pipeline, the first control end of the first switch valve connects 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. The winch overload protection 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. The winch overload protection 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. The winch overload protection 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 overload protection 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.

6. The winch overload protection system according to claim 1, characterized in that: A first shuttle valve is provided between the second control end of the first switch valve and the A end of the first control reversing valve, the first port of the first shuttle valve is connected to the A end of the first control reversing valve, the second port of the first shuttle valve is connected to the oil tank, and the third port of the first shuttle valve is connected to the second control end of the first switch valve.

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