CN117902501A - Hydraulic control system for brake of winch - Google Patents

Abstract

The disclosure provides a hydraulic control system of a brake of a winch, and belongs to the technical field of hydraulic control. The hydraulic control system comprises a power unit, an oil inlet unit and an oil return unit, wherein the oil inlet unit is communicated with the power unit and is used for controlling pressure oil from the power unit to enter into one of a first brake and a second brake respectively, the first brake is used for carrying out emergency braking on the winch when the winch encounters an accident, and the second brake is used for braking the winch when the winch works; the oil return unit is respectively communicated with the first brake and the second brake and is used for selectively leading the pressure oil in the first brake and the second brake into the oil tank. The present disclosure may improve the braking efficiency of the winch.

Description

Hydraulic control system for brake of winch

Technical Field

The disclosure belongs to the technical field of hydraulic control, and particularly relates to a hydraulic control system of a brake of a winch.

Background

The winch is a light and small hoisting device which is used for lifting or pulling heavy objects through winding a steel wire rope or a chain by a winding drum. The winch is widely applied to the fields of ocean engineering, ships, coal mines, wharfs, mines, roads and bridges and the like because of the advantages of simple operation and strong load capacity.

In the related art, a winch is generally equipped with a safety brake system including a brake and a hydraulic control system for controlling the brake. The hydraulic control system generally comprises a power unit, an oil inlet unit, an oil return unit and the like, wherein the oil inlet unit is used for conveying pressure oil to a brake so as to drive the brake to open or close. When the brake is opened, the winch is released from braking, and when the brake is closed, the winch is braked. The oil return unit is used for recovering oil in the brake.

However, the above system can only control one brake, so that when the winch needs to be braked during working or emergency braking is needed during accidents, the above system can only drive one brake to be closed. As is well known, the brake is worn during long-term use, so that when the winch is braked emergently in the above system, the winch cannot be braked due to the wear of the brake, and the braking effect of the winch is finally affected.

Disclosure of Invention

The embodiment of the disclosure provides a hydraulic control system for a brake of a winch, which controls two brakes simultaneously through one system, so that the winch can brake through a corresponding brake respectively when in operation and when in emergency braking, and the emergency braking efficiency of the winch is improved. The technical scheme is as follows:

The embodiment of the disclosure provides a hydraulic control system of a winch brake, which comprises a power unit, an oil inlet unit and an oil return unit, wherein the oil inlet unit is communicated with the power unit and is used for selectively controlling pressure oil pumped out of an oil tank by the power unit to enter a first brake and a second brake respectively, the first brake is used for carrying out emergency braking on the winch when the winch encounters accidents, and the second brake is used for carrying out braking on the winch when the winch works; the oil return unit is respectively communicated with the first brake and the second brake and is used for selectively controlling the pressure oil in the first brake and the second brake to be recovered into the oil tank.

In still another implementation manner of the present disclosure, the oil inlet unit includes a first electromagnetic two-position reversing valve, a second electromagnetic two-position reversing valve, and a third electromagnetic two-position reversing valve, an oil inlet of the first electromagnetic two-position reversing valve is communicated with a pressure oil port of the power unit, a first oil port of the first electromagnetic two-position reversing valve is communicated with an oil inlet of the second electromagnetic two-position reversing valve, a second oil port of the first electromagnetic two-position reversing valve is communicated with an oil inlet of the third electromagnetic two-position reversing valve, an oil outlet of the second electromagnetic two-position reversing valve is communicated with the first brake, and an oil outlet of the third electromagnetic two-position reversing valve is communicated with the second brake.

In yet another implementation of the present disclosure, the oil return unit includes a first oil return valve group and a second oil return valve group; the first oil return valve group comprises a first oil return reversing valve, a first direct unloading reversing valve, a constant speed reducing reversing valve and a constant speed reducing overflow valve, an oil inlet of the first oil return reversing valve is communicated with the first brake, an oil outlet of the first oil return reversing valve is respectively communicated with an oil inlet of the first direct unloading reversing valve and an oil inlet of the constant speed reducing overflow valve, an oil return port of the first direct unloading reversing valve is communicated with the oil tank, an oil outlet of the constant speed reducing overflow valve is communicated with an oil inlet of the constant speed reducing reversing valve, a control oil port of the constant speed reducing overflow valve is communicated with an oil inlet of the constant speed reducing overflow valve, a spring cavity of the constant speed reducing overflow valve is communicated with an oil outlet of the constant speed reducing overflow valve, and an oil return port of the constant speed reducing reversing valve is communicated with the oil tank; the second oil return valve group comprises a second oil return reversing valve, a second direct unloading reversing valve, a first working reversing valve and a first working overflow valve, an oil inlet of the second oil return reversing valve is communicated with the second brake, an oil outlet of the second oil return reversing valve is respectively communicated with an oil inlet of the second direct unloading reversing valve and the first working overflow valve, an oil return port of the second direct unloading reversing valve is communicated with the oil tank, an oil outlet of the first working overflow valve is communicated with an oil inlet of the first working reversing valve, a control oil port of the first working overflow valve is communicated with an oil inlet of the first working overflow valve, and an oil return port of the first working reversing valve is communicated with the oil tank.

In yet another implementation manner of the present disclosure, the first oil return valve group further includes a constant torque reversing valve and a constant torque overflow valve, an oil inlet of the constant torque overflow valve is communicated with an oil outlet of the first oil return reversing valve, an oil outlet of the constant torque overflow valve is communicated with an oil inlet of the constant torque reversing valve, a control oil port of the constant torque overflow valve is communicated with an oil inlet of the constant torque reversing valve, and a spring cavity of the constant torque overflow valve is communicated with an oil outlet of the constant torque overflow valve; and an oil return port of the constant moment reversing valve is communicated with the oil tank.

In still another implementation manner of the present disclosure, the first oil return valve group further includes an emergency overflow valve, a first emergency speed valve, a first emergency braking reversing valve, and a second emergency braking reversing valve, an oil inlet of the emergency overflow valve is communicated with an oil outlet of the first oil return reversing valve, an oil outlet of the emergency overflow valve is communicated with an oil inlet of the first emergency braking reversing valve, an oil return port of the first emergency braking reversing valve is communicated with the oil tank, an oil inlet of the first emergency speed valve is communicated with an oil outlet of the first oil return reversing valve and an oil inlet of the emergency overflow valve, an oil outlet of the first emergency speed valve is communicated with an oil inlet of the second emergency braking reversing valve, an oil outlet of the second emergency braking reversing valve is communicated with an oil inlet of the first emergency braking reversing valve, and the first emergency braking reversing valve is delayed to be turned on compared with the second emergency braking reversing valve.

In yet another implementation manner of the present disclosure, the second oil return valve group further includes a second working directional valve and a second working overflow valve, an oil inlet of the second working overflow valve is communicated with an oil outlet of the second oil return directional valve, an oil outlet of the second working overflow valve is communicated with an oil inlet of the second working directional valve, a control oil port of the second working directional valve is communicated with an oil inlet of the second working directional valve, and an oil return port of the second working directional valve is communicated with the oil tank.

In yet another implementation manner of the present disclosure, the second oil return valve group further includes a second emergency speed valve and a third emergency braking reversing valve, an oil inlet of the second emergency speed valve is communicated with an oil outlet of the second oil return reversing valve, an oil outlet of the second emergency speed valve is communicated with an oil inlet of the third emergency braking reversing valve, and an oil return port of the third emergency braking reversing valve is communicated with the oil tank.

In yet another implementation manner of the disclosure, the hydraulic control system further includes a first energy charging unit and a second energy charging unit with the same structure, where the first energy charging unit and the second energy charging unit are connected in parallel with each other and are both connected between the first electromagnetic two-position reversing valve and the second electromagnetic two-position reversing valve, and the first energy charging unit includes a first energy charging check valve, a first energy charging reversing valve, a first energy charging speed regulating valve, a first energy accumulator, and a first energy charging safety valve; the oil inlet of the first energy charging one-way valve is communicated with the first oil port of the first electromagnetic two-position reversing valve, the oil outlet of the first energy charging one-way valve is communicated with the first energy accumulator, the oil inlet of the first energy charging reversing valve is communicated with the first oil port of the first electromagnetic two-position reversing valve, the oil outlet of the first energy charging reversing valve is communicated with the oil inlet of the first energy charging speed regulating valve, the oil outlet of the first energy charging speed regulating valve is communicated with the first energy accumulator, the oil inlet of the first energy charging safety valve is communicated with the oil outlet of the first energy charging speed regulating valve, the oil return port of the first energy charging safety valve is communicated with the oil tank, the control oil port of the first energy charging safety valve is communicated with the oil inlet of the first energy charging safety valve, and the spring cavity of the first energy charging safety valve is communicated with the oil outlet of the first energy charging safety valve.

In yet another implementation of the present disclosure, the hydraulic control system further includes a third energy charging unit connected between the first electromagnetic two-position directional valve and the third electromagnetic two-position directional valve, the third energy charging unit being identical in structure to the first energy charging unit.

In yet another implementation of the present disclosure, the power unit includes a driving pump, a power overflow valve and a power reversing valve, an oil suction port of the driving pump is communicated with the oil tank, an oil pressing port of the driving pump is communicated with an oil inlet of the power overflow valve, an oil outlet of the power overflow valve is communicated with the oil tank, an oil control port of the power overflow valve is communicated with an oil inlet of the power overflow valve, a spring cavity of the power overflow valve is communicated with the oil inlet of the power reversing valve, and an oil return port of the power reversing valve is communicated with the oil tank.

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

The hydraulic control system comprises a power unit, an oil inlet unit and an oil return unit, wherein the oil inlet unit is communicated with the power unit and is used for selectively controlling pressure oil pumped out of an oil tank by the power unit to enter a first brake and a second brake respectively, the oil return unit is communicated with the first brake and the second brake respectively, and the oil return unit is used for selectively controlling the pressure oil in the first brake and the second brake to be recovered into the oil tank, so that the first brake and the second brake can be controlled to be switched on or off respectively through the oil inlet unit and the oil return unit in the system, and further different brakes can be realized on a winch.

For example, when the winch works normally, the winch needs to be braked, at the moment, the winch can be stopped by controlling the oil inlet unit and the oil return unit, and after the winch is decelerated to a certain rotating speed through a driving motor and the like, the winch can be rapidly switched on through controlling the second brake. When the winch is unexpected (such as the winch overspeed, the sliding of the winch or the slipping of a steel wire rope, and the like), the winch needs to be braked urgently, and at the moment, the oil inlet unit and the oil return unit can be controlled, so that the first brake is switched on smoothly to stop the winch.

Drawings

In order to more clearly illustrate the technical solutions of the embodiments of the present disclosure, the drawings required for the description of the embodiments will be briefly introduced below, and it is obvious that the drawings in the following description are only some embodiments of the present disclosure, and other drawings may be obtained according to these drawings without inventive effort for a person of ordinary skill in the art.

FIG. 1 is a schematic diagram of a hydraulic control system for a brake of a winch provided in an embodiment of the present disclosure;

FIG. 2 is a schematic diagram of a hydraulic control system for a brake of another winch provided in an embodiment of the present disclosure;

FIG. 3 is an enlarged view of portion A of FIG. 2;

fig. 4 is an enlarged view of part B of fig. 2;

FIG. 5 is an enlarged view of a portion of the power unit of FIG. 2;

FIG. 6 is an enlarged view of portion C of FIG. 2;

FIG. 7 is a schematic diagram of a hydraulic control system for use with two pump stations simultaneously provided in an embodiment of the present disclosure.

The symbols in the drawings are as follows:

1. a power unit; 11. driving a pump; 12. a power overflow valve; 13. a power reversing valve; 14. a power filter; 15. a power check valve;

2. An oil inlet unit; 21. a first electromagnetic two-position reversing valve; 22. the second electromagnetic two-position reversing valve; 23. a third electromagnetic two-position reversing valve;

3. An oil return unit; 31. the first oil return valve group; 310. the first oil return reversing valve; 311. a first direct unloading reversing valve; 312. a constant speed reducing reversing valve; 313. a constant speed reducing overflow valve; 314. a constant torque reversing valve; 315. a constant torque overflow valve; 316. an emergency overflow valve; 317. a first emergency speed valve; 318. a first emergency brake reversing valve; 319. a second emergency braking reversing valve; 32. the second oil return valve group; 320. the second oil return reversing valve; 321. a second direct-unloading reversing valve; 322. a first working reversing valve; 323. a first working relief valve; 325. a second working reversing valve; 326. a second working relief valve; 327. a second emergency speed valve; 328. a third emergency braking reversing valve;

4. A first charging unit; 41. a first charge check valve; 42. a first charge diverter valve; 43. a first charge speed control valve; 44. a first accumulator; 45. a first charge safety valve;

5. A second charging unit; 51. a second charge check valve; 52. a second charge reversing valve; 53. a second charging speed regulating valve; 54. a second accumulator; 55. a second charge safety valve;

7. a third charging unit; 71. a third charge check valve; 72. a third charge reversing valve; 73. a third energy-charging speed regulating valve; 74. a third accumulator; 75. a third charge safety valve;

8. A cooling unit; 81. a cooling pump; 82. a cooler; 83. cooling the one-way valve; 84. cooling the filter; 811. a first three-way ball valve; 812. a first quick connector; 841. a second three-way ball valve; 842. a second quick connector;

100. A first brake; 200. a second brake; 300. a pressure sensor; 400. a pressure gauge; 500. and a pump station switching valve.

Detailed Description

For the purposes of clarity, technical solutions and advantages of the present disclosure, the following further details the embodiments of the present disclosure with reference to the accompanying drawings.

The embodiment of the disclosure provides a hydraulic control system of a brake of a winch, and as shown in fig. 1, the hydraulic control system comprises a power unit 1, an oil inlet unit 2 and an oil return unit 3.

The oil inlet unit 2 is communicated with the power unit 1 and is used for controlling pressure oil from the power unit 1 to enter one of the first brake 100 and the second brake 200 respectively, the first brake 100 is used for emergency braking of the winch when the winch encounters accidents, and the second brake 200 is used for braking of the winch when the winch works.

The oil return unit 3 communicates with the first brake 100 and the second brake 200, respectively, and the oil return unit 3 is configured to selectively introduce the pressure oil in the first brake 100 and the second brake 200 into the oil tank.

Because the hydraulic control system comprises the power unit 1, the oil inlet unit 2 and the oil return unit 3, the oil inlet unit 2 is communicated with the power unit 1 and is used for controlling pressure oil from the power unit 1 to enter into one of the first brake 100 and the second brake 200 respectively, the oil return unit 3 is communicated with the first brake 100 and the second brake 200 respectively, and the oil return unit 3 is used for selectively guiding the pressure oil in the first brake 100 and the second brake 200 into an oil tank, so that the first brake 100 and the second brake 200 can be controlled to be closed or opened respectively through the oil inlet unit 2 and the oil return unit 3 in the system, and further different brakes can be realized on the winch.

For example, when the winch works normally, the winch needs to be braked, at the moment, the driving motor is controlled to be decelerated, and then after the winch speed is reduced to a certain rotating speed, the winch can be decelerated until the winch is stopped by controlling the oil inlet unit 2 and the oil return unit 3 to enable the second brake 200 to be switched on quickly. When an accident (such as overspeed, sliding or slipping of a wire rope) occurs and the winch needs to be braked suddenly, the oil inlet unit 2 and the oil return unit 3 can be controlled at the moment, so that the first brake 100 is closed smoothly to stop the winch at the original speed.

In this embodiment, the second brake 200 is also a high-speed brake for performing service braking on the winch. The working brake refers to the brake that the winch is decelerated or stopped when working, and the brake is to control the rotation speed of the driving motor to be reduced first, and then the winch is rapidly braked by the second brake 200 until the winch stops rotating after the rotation speed of the winch is reduced.

The first brake 100 is a safety brake for safety braking of the winch. Safety braking refers to the fact that in the event of a special situation of the winch, such as overspeed, slipping or rope slipping, the first brake 100 will in that case apply a brake directly to the winch, which is also called emergency braking.

The first brake 100 and the second brake 200 are the same in structure and are both disc brakes. The disc brake is tightly held on by a belleville spring in a default state, and the brake is opened by using a pressure oil compression spring. The working principle is to change the oil pressure to adjust the braking force. When the winch works, the first brake and the second brake are in an open state, the oil pressure is rated working pressure of the first brake and the second brake, and braking forces of the first brake and the second brake are 0. When the winch needs to be braked, the hydraulic control system automatically adjusts the oil pressure, and the braking force is changed to achieve the braking requirement. The first brake 100 is opened first during normal opening, and then the second brake 200 is opened again after the torque of the driving motor of the winch is established. The second brake 200 is first closed during normal closing, and then the first brake 100 is closed again. However, when an accident occurs, such as an accident of a driving motor of the winch, the winch needs to be braked suddenly, at this time, the winch is braked directly by switching on the first brake 100 to stop the winch, and the second brake 200 is switched on after the winch stops.

In addition, during assembly, the first brakes 100 are symmetrically arranged on the front and rear sides of the brake discs on both sides of the winch drum, and the second brakes 200 are symmetrically arranged on both sides of the winch speed reducer and the motor connecting shaft brake disc.

Fig. 2 is a schematic diagram of a hydraulic control system of a brake of another winch according to an embodiment of the present disclosure, and in combination with fig. 2, optionally, the oil inlet unit 2 includes a first electromagnetic two-position directional valve 21, a second electromagnetic two-position directional valve 22, and a third electromagnetic two-position directional valve 23, an oil inlet of the first electromagnetic two-position directional valve 21 is communicated with a pressure oil port of the power unit 1, a first oil port of the first electromagnetic two-position directional valve 21 is communicated with an oil inlet of the second electromagnetic two-position directional valve 22, and a second oil port of the first electromagnetic two-position directional valve 21 is communicated with an oil inlet of the third electromagnetic two-position directional valve 23. The oil outlet of the second electromagnetic two-position reversing valve 22 is communicated with the first brake 100, and the oil outlet of the third electromagnetic two-position reversing valve 23 is communicated with the second brake 200.

In the above-described implementation, the first electromagnetic two-way directional valve 21 is used to control whether the power unit 1 is in communication with the second electromagnetic two-way directional valve 22 and the third electromagnetic two-way directional valve 23. While the second electromagnetic two-way directional valve 22 is used to control whether the first electromagnetic two-way directional valve 21 is in communication with the first brake 100, and the third electromagnetic two-way directional valve 23 is used to control whether the first electromagnetic two-way directional valve 21 is in communication with the second brake.

When the first electromagnetic two-position directional valve 21 loses power, the oil inlet P of the first electromagnetic two-position directional valve 21 is communicated with the first oil port, namely, the oil pumped out by the power unit 1 can enter the second electromagnetic two-position directional valve 22 (the second electromagnetic two-position directional valve 22 loses power), and at the moment, the oil directly enters the first brake 100 through the second electromagnetic two-position directional valve 22. When the first electromagnetic two-position directional valve 21 is powered on, the oil inlet P of the first electromagnetic two-position directional valve 21 is communicated with the second oil port, i.e., the oil pumped out by the power unit 1 can enter the third electromagnetic two-position directional valve 23 (the third electromagnetic two-position directional valve 23 loses power), and at this time, the oil directly enters the second brake 200 through the third electromagnetic two-position directional valve 23.

In the embodiment, the winch is applied to mining production, and the winch drives the lift car (internally carrying mineral workers) to lift. The number of the winches is generally two, and the two winches drive the lift car to lift. Correspondingly, the first brakes 100 are two sets, and the second brakes 200 are two sets.

And the second electromagnetic two-position directional valve 22 and the third electromagnetic two-position directional valve 23 are also two. Wherein the second electromagnetic two-position directional valve 22 is arranged in one-to-one correspondence with the first brake 100, and the third electromagnetic two-position directional valve 23 is arranged in one-to-one correspondence with the second brake 200.

Optionally, the oil return unit 3 comprises a first oil return valve group 31 and a second oil return valve group 32.

Fig. 3 is an enlarged view of a portion a of fig. 2, and in combination with fig. 3, the first oil return valve group 31 includes a first oil return directional valve 310, a first direct unloading directional valve 311, a constant speed reduction directional valve 312, and a constant speed reduction relief valve 313, an oil inlet of the first oil return directional valve 310 is communicated with the first brake 100, an oil outlet of the first oil return directional valve 310 is respectively communicated with an oil inlet of the first direct unloading directional valve 311 and an oil inlet of the constant speed reduction relief valve 313, an oil return port of the first direct unloading directional valve 311 is communicated with an oil tank, an oil outlet of the constant speed reduction relief valve 313 is communicated with an oil inlet of the constant speed reduction directional valve 312, a control oil port of the constant speed reduction relief valve 313 is communicated with an oil inlet of the constant speed reduction relief valve 313, a spring chamber of the constant speed reduction relief valve 313 is communicated with an oil outlet of the constant speed reduction directional valve 312, and an oil return port of the constant speed reduction directional valve 312 is communicated with an oil tank.

In the above-described implementation, the first return oil switching valve 310 is used to control whether the first brake 100 is in communication with the first direct-load-dump switching valve 311 and the constant-speed relief valve 313.

The first direct unloading reversing valve 311 is used for directly unloading the first brake 100 for oil return, so as to ensure that the oil pressure in the first brake 100 is 0. The constant deceleration directional valve 312 and the constant deceleration relief valve 313 cooperate with each other to allow the winch to stop at a constant deceleration when the first brake 100 emergency-brakes the winch. Meanwhile, by setting the set pressure of the constant-speed reduction relief valve 313 to the rated operating pressure of the first brake 100, the first brake 100 is kept open at the rated operating pressure so that the first brake 100 can achieve the required brake clearance.

In this embodiment, the constant-speed-reduction overflow valve 313 is an electromagnetic proportional overflow valve, and by monitoring the speed of the constant-speed-reduction overflow valve 313, the braking force of the first brake 100 can be dynamically changed, so that the first brake 100 can perform constant-speed-reduction braking on the winch.

Optionally, the first oil return valve group 31 further includes a constant moment reversing valve 314 and a constant moment overflow valve 315, wherein an oil inlet of the constant moment overflow valve 315 is communicated with an oil outlet of the first oil return reversing valve 310, an oil outlet of the constant moment overflow valve 315 is communicated with an oil inlet of the constant moment reversing valve 314, a control oil port of the constant moment overflow valve 315 is communicated with an oil inlet of the constant moment overflow valve 315, and a spring cavity of the constant moment overflow valve 315 is communicated with an oil outlet of the constant moment overflow valve. The return port of the constant torque reversing valve 314 communicates with the tank.

In the above implementation, the constant-torque reversing valve 314 and the constant-torque overflow valve 315 cooperate with each other to enable the winch to stop at a constant torque when the first brake 100 performs emergency braking on the winch. At the same time, the first brake 100 is kept open at the rated operating pressure by setting the set pressure of the constant-torque relief valve 315 to the rated operating pressure of the first brake 100, so that the first brake 100 can achieve the required brake clearance.

The constant moment overflow valve 315 is also an electromagnetic proportional overflow valve, and is different from the constant speed reduction overflow valve 313 in use, the constant moment overflow valve 315 is a preset pressure value in use, and cannot be dynamically adjusted, but the constant speed reduction overflow valve 313 often needs to be dynamically adjusted.

That is, the above arrangement may enable the first brake 100 to achieve constant torque braking and constant deceleration braking, respectively. However, as is conventional in use, the winch is typically stopped at a constant speed by the first brake 100, and if the constant speed fails, the winch is stopped at a constant torque by switching to constant torque braking.

Optionally, the first oil return valve group 31 further includes an emergency overflow valve 316, a first emergency speed control valve 317, a first emergency braking reversing valve 318, and a second emergency braking reversing valve 319, where an oil inlet of the emergency overflow valve 316 is communicated with an oil outlet of the first oil return reversing valve 310, an oil outlet of the emergency overflow valve 316 is communicated with an oil inlet of the first emergency braking reversing valve 318, and an oil return port of the first emergency braking reversing valve 318 is communicated with an oil tank. The oil inlet of the first emergency speed control valve 317 is communicated with the oil outlet of the first oil return reversing valve 310 and the oil inlet of the emergency overflow valve 316, the oil outlet of the first emergency speed control valve 317 is communicated with the oil inlet of the second emergency braking reversing valve 319, and the oil outlet of the second emergency braking reversing valve 319 is communicated with the oil inlet of the first emergency braking reversing valve 318. The second emergency brake directional valve 319 is turned on with a delay compared to the first emergency brake directional valve 318.

In the above implementation, the above arrangement may be used to release the pressure in the first brake 100 after the winch speed is reduced to 0 after the first brake 100 performs emergency braking on the winch, so that the pressure in the first brake 100 is slowly reduced to 0.

The first emergency braking reversing valve 318 and the second emergency braking reversing valve 319 are normally closed two-position two-way electromagnetic valves, namely, in the power-on state, the oil inlet of the first emergency braking reversing valve 318 is communicated with the oil outlet, and the oil inlet of the second emergency braking reversing valve 319 is communicated with the oil outlet.

The second emergency brake directional valve 319 is controlled by a first power loss delay relay. Wherein the first de-energized delay relay is integrated in a controller for controlling the opening and closing of the second emergency brake directional valve 319. Thus, when the system is powered down, the second emergency brake directional valve 319 will control the spool movement for a later period of time (typically within 1-10S) under the control of the first power loss delay relay, such that the second emergency brake directional valve 319 is in a power loss state.

When the power supplies in the above systems fail, at this time, the first emergency braking directional valve 318 and the second emergency braking directional valve 319 (the first power-off delay relay is controlled to be powered off later) are in a power-off state, and the corresponding valve spools are located in the lower positions. The oil inlet and the oil outlet of the first emergency braking reversing valve 318 are communicated, and the oil inlet and the oil outlet of the second emergency braking reversing valve 319 are communicated.

Thus, when the system is powered down, the second emergency braking reversing valve 319 is controlled by the first power-down delay relay, so that the oil return in the first brake 100 is conducted with the oil tank through the emergency relief valve 316 and the first emergency braking reversing valve 318, the pressure in the first brake 100 is quickly reduced to the maximum static unbalanced tension, and the winch achieves half brake. After that, the second emergency braking reversing valve 319 is turned off and turned on after a delay, and the pressure in the first brake 100 is slowly reduced to 0 through the first emergency speed regulating valve 317 and the second emergency braking reversing valve 319, so that the winch is slowly and stably braked. The first emergency speed valve 317 is used to control the closing time.

Fig. 4 is an enlarged view of part B of fig. 2, and in combination with fig. 4, the second oil return valve group 32 includes a second oil return directional valve 320, a second direct unloading directional valve 321, a first working directional valve 322, and a first working relief valve 323, an oil inlet of the second oil return directional valve 320 is communicated with the second brake 200, an oil outlet of the second oil return directional valve 320 is respectively communicated with an oil inlet of the second direct unloading directional valve 321 and the first working relief valve 323, an oil return port of the second direct unloading directional valve 321 is communicated with an oil tank, an oil outlet of the first working relief valve 323 is communicated with an oil inlet of the first working directional valve 322, a control oil port of the first working relief valve 323 is communicated with an oil inlet of the first working relief valve 322, and an oil return port of the first working directional valve 322 is communicated with the oil tank.

The second return directional valve 320 is used to control whether the second brake 200 is connected to the second direct unloading directional valve 321 and the first working relief valve 323. The second direct-unloading directional valve 321 is used to directly unload the second brake 200 back to oil. The first working direction valve 322 and the first working relief valve 323 cooperate with each other to maintain the rated working pressure of the second brake 200 when the brake is opened, so that the second brake 200 can achieve a required brake clearance.

That is, when the first working direction valve 322 is electrified, the return oil of the second brake 200 is conducted to the tank through the first working relief valve 323 and the first working direction valve 322, the first working relief valve 323 is set to the rated working pressure of the second brake 200, and the system is kept open at the rated working pressure.

Optionally, the second oil return valve group 32 further includes a second working reversing valve 325 and a second working overflow valve 326, where an oil inlet of the second working overflow valve 326 is communicated with an oil outlet of the second oil return reversing valve 320, an oil outlet of the second working overflow valve 326 is communicated with an oil inlet of the second working reversing valve 325, a control oil port of the second working overflow valve 326 is communicated with an oil inlet of the second working overflow valve 326, and an oil return port of the second working overflow valve 326 is communicated with an oil tank.

In the above implementation, the second working directional valve 325 is used to control whether the second brake 200 is connected to the tank, and the second working relief valve 326 is used to limit the return oil pressure in the second brake 200, so that the second brake 200 can maintain the rated working pressure when the brake is opened.

The second working direction valve 325 and the second working relief valve 326 are used as alternatives to the first working direction valve 322 and the first working relief valve 323 when the first working direction valve 322 and the first working relief valve 323 fail.

Optionally, the second oil return valve group 32 further includes a second emergency speed valve 327 and a third emergency braking reversing valve 328, an oil inlet of the second emergency speed valve 327 is communicated with an oil outlet of the second oil return reversing valve 320, an oil outlet of the second emergency speed valve 327 is communicated with an oil inlet of the third emergency braking reversing valve 328, and an oil return port of the third emergency braking reversing valve 328 is communicated with an oil tank.

In the above implementation, the second emergency speed valve 327 and the third emergency braking reversing valve 328 are also in the event of a power failure of the system, so that the second brake 200 can still be closed by closing.

Wherein the third emergency brake directional valve 328 is controlled by a second power loss delay relay. Wherein the second de-energized delay relay is integrated in a controller for controlling the opening and closing of the third emergency brake directional valve 328. Thus, when the system is powered down, the third emergency brake directional valve 328 will control the movement of the spool for a later period of time (typically within 5-20S) under the control of the second power loss delay relay, so that the third emergency brake directional valve 328 is in a power loss state. The delayed power loss time of the third emergency brake directional valve 328 is greater than the delayed power loss time of the second emergency brake directional valve 319.

When the system is powered down, the return oil in the second brake 200 can be reduced in speed through the second emergency speed control valve 327, and after a period of time, the return oil can return to the oil tank through the third emergency braking reversing valve 328.

In this embodiment, since the third emergency braking direction valve 328 is controlled by the second power-off delay relay, and the time-delay power-off time of the third emergency braking direction valve 328 is longer than the time-delay power-off time of the second emergency braking direction valve 319, it is avoided that the second brake 200 starts braking when the first brake 100 is half-braked. Because the third emergency braking directional valve 328 is only turned on after the first brake 100 is turned on and the full brake is turned on, the second brake 200 is controlled to be turned on. The pressure in the second brake 200 is slowly reduced to 0 through the third emergency braking reversing valve 328 and the second emergency speed valve 327, so that the second brake 200 is closed.

Optionally, referring to fig. 3, the hydraulic control system further includes a first energy charging unit 4 and a second energy charging unit 5, where the first energy charging unit 4 and the second energy charging unit 5 have the same structure, and are connected in parallel to each other, and are both connected between the first electromagnetic two-position reversing valve 21 and the second electromagnetic two-position reversing valve 22. The first charging unit 4 includes a first charging check valve 41, a first charging reversing valve 42, a first charging speed valve 43, a first accumulator 44, and a first charging safety valve 45.

The oil inlet of the first energy charging one-way valve 41 is communicated with the first oil port of the first electromagnetic two-position reversing valve 21, the oil outlet of the first energy charging one-way valve 41 is communicated with the first accumulator 44, the oil inlet of the first energy charging reversing valve 42 is communicated with the first oil port of the first electromagnetic two-position reversing valve 21, the oil outlet of the first energy charging reversing valve 42 is communicated with the oil inlet of the first energy charging speed regulating valve 43, the oil outlet of the first energy charging speed regulating valve 43 is communicated with the first accumulator 44, the oil inlet of the first energy charging safety valve 45 is communicated with the oil outlet of the first energy charging speed regulating valve 43, the oil return port of the first energy charging safety valve 45 is communicated with the oil tank, the control oil port of the first energy charging safety valve 45 is communicated with the oil inlet of the first energy charging safety valve 45, and the spring cavity of the first energy charging safety valve 45 is communicated with the oil outlet of the first energy charging safety valve 45.

The second charging unit 5 includes a second charging check valve 51, a second charging reversing valve 52, a second charging speed regulating valve 53, a second accumulator 54, and a second charging safety valve 55.

The oil inlet of the second energy charging one-way valve 51 is communicated with the first oil port of the first electromagnetic two-position reversing valve 21, the oil outlet of the second energy charging one-way valve 51 is communicated with the second accumulator 54, the oil inlet of the second energy charging one-way valve 52 is communicated with the second oil port of the first electromagnetic two-position reversing valve 21, the oil outlet of the second energy charging one-way valve 52 is communicated with the oil inlet of the second energy charging speed regulating valve 53, the oil outlet of the second energy charging speed regulating valve 53 is communicated with the second accumulator 54, the oil inlet of the second energy charging safety valve 55 is communicated with the oil outlet of the second energy charging speed regulating valve 53, the oil return port of the second energy charging safety valve 55 is communicated with the oil tank, the control oil port of the second energy charging safety valve 55 is communicated with the oil inlet of the second energy charging safety valve 55, and the spring cavity of the second energy charging safety valve 55 is communicated with the oil outlet of the second energy charging safety valve.

In the above-described embodiment, the first accumulator 44 performs auxiliary oil supply when the first brake 100 is opened, and the second accumulator 54 performs auxiliary oil supply when the first brake 100 is closed (safety brake). That is, the first accumulator 44 is used when the first brake 100 is opened by controlling the first charge switching valve 42, and the second accumulator 54 is used when the first brake 100 is closed by controlling the second charge switching valve 52. This allows the first brake to use two separate accumulator circuits for opening and safety braking, respectively. The first brake can be quickly opened by the combined action of the first energy accumulator 44 and the driving pump 11 when the brake is opened, so that the working efficiency is improved. In the event of failure of the drive pump 11, the first accumulator 44 can still effect a separate opening of the first brake, placing the car in a safe position. And the isolation of the two accumulator loops ensures that the accumulator has sufficient pressure at any time to perform safety braking.

In this embodiment, in order to be able to monitor the pressures of the first and second accumulators 44, 54 in real time, the first and second accumulators 44, 54 are provided with pressure sensors 300, respectively. The pressure sensor 300 monitors the oil pressure in each accumulator in real time.

In addition, in order to facilitate detection of the pressures of the first accumulator 44 and the second accumulator 54 when charged, a pressure gauge 400 may be connected between the first accumulator 44 and the first charge check valve 41, and between the second accumulator 54 and the second charge check valve 51, respectively.

Optionally, referring to fig. 4, the hydraulic control system further includes a third charging unit 7, where the third charging unit 7 is connected between the first electromagnetic two-position reversing valve 21 and the second electromagnetic two-position reversing valve 22, and the third charging unit 7 has the same structure as the first charging unit 4.

In the above implementation, the third charging unit 7 is used for supplementing the second brake 200 with oil.

The third charging unit 7 includes a third charging check valve 71, a third charging reversing valve 72, a third charging speed valve 73, a third accumulator 74, and a third charging safety valve 75.

The oil inlet of the third energy charging check valve 71 is communicated with the first oil port of the first electromagnetic two-position reversing valve 21, the oil outlet of the third energy charging check valve 71 is communicated with the third accumulator 74, the oil inlet of the third energy charging reversing valve 72 is communicated with the second oil port of the first electromagnetic two-position reversing valve 21, the oil outlet of the third energy charging reversing valve 72 is communicated with the oil inlet of the third energy charging speed regulating valve 73, the oil outlet of the third energy charging speed regulating valve 73 is communicated with the third accumulator 74, the oil inlet of the third energy charging safety valve 75 is communicated with the oil outlet of the third energy charging speed regulating valve 73, the oil return port of the third energy charging safety valve 75 is communicated with the oil tank, the control oil port of the third energy charging safety valve 75 is communicated with the oil inlet of the third energy charging safety valve 75, and the spring cavity of the third energy charging safety valve 75 is communicated with the oil outlet of the third energy charging safety valve.

Other structures are similar and are not described in detail herein.

Referring to fig. 2 and 5, alternatively, the power unit 1 includes a driving pump 11, a power overflow valve 12 and a power reversing valve 13, an oil suction port of the driving pump 11 is communicated with an oil tank, an oil pressing port of the driving pump 11 is communicated with an oil inlet of the power overflow valve 12, an oil outlet of the power overflow valve 12 is communicated with the oil tank, a control oil port of the power overflow valve 12 is communicated with an oil inlet of the power overflow valve, a spring cavity of the power overflow valve 12 is communicated with an oil inlet of the power reversing valve 13, and an oil return port of the power reversing valve 13 is communicated with the oil tank.

In the implementation manner, when the power reversing valve 13 is powered off, the oil inlet unit 2 can be controlled to be unloaded or loaded, and different pressure output requirements can be realized corresponding to each working condition of the brake. When the electromagnet of the power reversing valve 13 is de-energized, the pilot oil flowing to the power overflow valve 12 from the driving pump 11 directly flows to the oil tank, and at this time, the overflow pressure of the power reversing valve 13 is low, so that the output pressure of the driving pump 11 is low, and the driving pump 11 is in an unloading state. When the electromagnet of the power steering valve 13 is powered on, the pilot oil flowing to the power relief valve 12 from the driving pump 11 starts to act, and the relief pressure of the driving pump 11 can be adjusted by adjusting the set pressure of the power relief valve 12, so that the output pressure of the driving pump 11 is controlled.

Referring to fig. 2, optionally, the power unit 1 further includes a power filter 14 and a power check valve 15, the power filter 14 is connected to a pressure oil port of the driving pump 11, an oil inlet of the power filter 14 is communicated with the pressure oil port of the driving pump 11, an oil outlet of the power filter 14 is communicated with an oil inlet of the power check valve 15, and an oil outlet of the power check valve 15 is communicated with an oil inlet of the first electromagnetic two-position reversing valve 21.

In the above implementation, the power filter 14 is used to filter the oil pumped by the driving pump 11, so that the oil is kept clean.

Referring to fig. 6, optionally, the hydraulic control system further includes a cooling unit 8, where the cooling unit 8 includes a cooling pump 81, a cooler 82, a cooling check valve 83, and a cooling filter 84, an oil inlet of the cooling pump 81 is communicated with an oil tank, an oil inlet of the cooling pump 81 is communicated with an oil inlet of the cooler 82, an oil outlet of the cooling pump 81 is communicated with an oil inlet of the cooling check valve 83, an oil outlet of the cooling check valve 83 is communicated with an oil inlet of the cooling filter 84, and an oil outlet of the cooling filter 84 is communicated with the oil tank.

In the above implementation manner, when the oil temperature of the oil in the system is too high, the cooling pump 81 is started, the oil in the oil tank is absorbed and conveyed to the cooler 82 for cooling by the cooling pump 81, and the cooled oil is filtered by the cooling check valve 83 and the cooling filter 84 and then returns to the oil tank again, so that the oil can be cooled.

In addition, in order to facilitate the oil replenishment of the oil in the oil tank, the cooling pump 81 is provided with a first three-way ball valve 811 and a first quick connector 812 between the oil tanks, both ends of the first three-way ball valve 811 are respectively communicated with the oil tank and the cooling pump 81, the other end of the first three-way ball valve 811 is communicated with one end of the first quick connector 812, and the other end of the first quick connector 812 is used for being communicated with oil storage equipment such as an oil drum.

That is, when the oil tank needs to be replenished but the oil pump is not present, the first three-way ball valve 811 can be rotated to connect the first quick connector 812 to the oil pipe and then directly communicate with the oil tank. The cooling pump 81 is started again, so that the oil in the oil tank can be replenished to the oil tank after passing through the cooling filter 84, and the replenished oil can be kept clean.

Optionally, a second three-way ball valve 841 and a second quick connector 842 are connected between the cooling filter 84 and the cooling check valve 83, two ends of the second three-way ball valve 841 are respectively communicated with the cooling filter 84 and the cooling check valve 83, the other end of the second three-way ball valve 841 is communicated with one end of the second quick connector 842, and the other end of the second quick connector 842 is used for being communicated with a fuel pump and the like.

In the above arrangement, when the cooling pump 81 is damaged, the second three-way ball valve 841 may be rotated to communicate the second quick connector 842 with the cooling filter 84. The oil pump is used for connecting the second quick connector 842 to supplement the oil tank, and the cleanliness of the oil can be ensured by the cooling filter 84.

Referring to fig. 7, in this embodiment, there may be two systems. I.e. both systems are connected to the first brake and the second brake simultaneously, so that in case of a problem with one of the systems the other system is ready for use.

To facilitate switching between the two systems, the two systems are connected by a pump station switching valve 500.

The working procedure of the hydraulic control system provided by the embodiment of the present disclosure is briefly described below:

during normal opening, the first brake 100 is opened first, and then the second brake 200 is opened again after the torque of the driving motor of the winch is established.

After the driving pump 11 in the hydraulic system is started, the driving pump 11 sucks oil from the oil tank through the oil suction port. The electromagnet of the first direct-unloading switching valve 311 is energized, closing the direct-unloading circuit of the first brake 100. The electromagnets of the constant speed reduction reversing valve 312 and the constant speed reduction relief valve 313 are energized, and the pressure of the constant speed reduction relief valve 313 is adjusted to the rated operating pressure of the first brake 100. And then controlling the electromagnet of the power reversing valve 13 to be electrified, and loading the power overflow valve 12. The electromagnet of the first charging reversing valve 42 in the first charging unit 4 is controlled to be powered, the first accumulator 44 and the driving pump 11 simultaneously supply oil to the first brake 100, and the spring is compressed, so that the first brake 100 is opened. After the motor torque is established, the electromagnet of the first working directional valve 322 is powered, and the first working relief valve 323 is set to be the rated working pressure of the second brake 200. The third emergency brake directional valve 328 is energized, closing the emergency brake circuit. The electromagnet of the first electromagnetic two-position reversing valve 21 and the electromagnet of the third energy charging reversing valve 72 in the third energy charging unit 7 are controlled to be powered, the pressure oil pumped by the driving pump 11 and the third energy accumulator 74 simultaneously supply oil to the second brake 200, and the spring is compressed, so that the second brake 200 is opened.

When the first brake 100 and the second brake 200 are kept in the open state, the first accumulator 44 and the third accumulator 74 are charged with oil, and the pressure sensor 300 monitors the oil pressure of each accumulator in real time. When the pressure of the first accumulator 44 or the third accumulator 74 decreases to the set value PA1, the power steering valve 13 is powered, the power relief valve 12 is reloaded, and the pump 11 is driven to charge the first accumulator 44 and the third accumulator 74. When the pressure of the first accumulator 44 and the pressure of the third accumulator 74 rise to the set value PB1, the power steering valve 13 is de-energized, the power relief valve 12 is unloaded, and the drive pump 11 stops charging the first accumulator 44 or the third accumulator 74. When the pressure of the third accumulator 74 is reduced to the set value PA2, the power reversing valve 13 and the first electromagnetic two-position reversing valve 21 are both electrified, the power overflow valve 12 is loaded, and the hydraulic pump charges the third accumulator 74. When the pressure of the third accumulator 74 rises to the set value PB2, the power steering valve 13 and the first electromagnetic two-position steering valve 21 lose electricity, the power relief valve 12 is unloaded, and the hydraulic pump stops charging the third accumulator 74.

When closing, the second brake 200 is closed first, and then the first brake 100 is closed again. When the rotation speed of the driving motor of the winch is reduced to the speed at which the second brake 200 can be smoothly switched on, the power reversing valve 13 is controlled to lose electricity, and the power overflow valve 12 is unloaded. The first electromagnetic two-way directional valve 21 and the third charge directional valve 72 are de-energized, driving the pump 11 and the third accumulator 74 while stopping the supply of oil to the second brake 200. The first working directional valve 322 and the third emergency braking directional valve 328 are powered off, the second direct unloading directional valve 321 is powered on, and hydraulic oil in the second brake 200 is quickly released through the second direct unloading directional valve, so that the closing of the second brake is realized. After the second brake 200 is closed, the second emergency braking reversing valve 319, the constant speed reducing reversing valve 312, the constant speed reducing overflow valve 313 and the second charging reversing valve 52 in the second charging unit 5 are controlled to lose electricity, and the driving pump 11 and the second accumulator 54 stop supplying oil to the safety brake at the same time. The second direct unloading reversing valve 321 is powered on, and hydraulic oil in the first brake rapidly passes through the second direct unloading reversing valve 321 to relieve pressure, so that the first brake 100 is switched on.

If the winch is unexpected, and the winch needs to be braked urgently, the winch is braked directly by switching on the first brake 100. The second brake 200 is maintained in an open state,

When the emergency braking is triggered, the first brake 100 is closed, and the system automatically turns to constant-speed-reduction safety braking. The first charge diverter valve 42 is de-energized and the second charge diverter valve 52 is energized, using the first accumulator 44 to recharge the constant deceleration brake. According to the winch speed, the valve core opening of the constant speed reduction relief valve 313 is dynamically adjusted, so that the system pressure is controlled, and the winch is kept at constant speed reduction. When the winch speed drops to 0, the second emergency braking directional valve 319, the constant speed reduction directional valve 312, the constant speed reduction relief valve 313, and the second charging directional valve 52 are de-energized, and the second accumulator 54 stops supplying oil to the first brake 100. The first direct unloading reversing valve 311 is powered on, and hydraulic oil in the first brake rapidly releases pressure through the first direct unloading reversing valve 311, so that the first brake is switched on. After the first brake 100 is closed, the second working directional valve 325 is de-energized and the third accumulator 74 stops supplying oil to the second brake. The first working directional valve 322 and the third emergency braking directional valve 328 are powered off, the second direct unloading directional valve 321 is powered on, and hydraulic oil in the second brake 200 is quickly relieved through the second direct unloading directional valve 321, so that the closing of the second brake is realized.

If the constant deceleration braking mode of the first brake 100 fails, the constant torque braking mode is automatically shifted. The second brake 200 keeps an open state, the constant speed reduction reversing valve 312, the constant speed reduction overflow valve 313 are powered off, the constant moment overflow valve 315 and the constant moment reversing valve 314 are powered on, the pressure of the system is regulated to be the maximum static unbalanced tension, and the winch realizes half brake. After the time delay, the second emergency braking reversing valve 319, the constant moment reversing valve 314, the constant moment overflow valve 315 and the first charging reversing valve 42 are de-energized, and the second accumulator 54 stops the supply of oil to the first brake. The first direct unloading reversing valve 311 is powered on, and hydraulic oil in the first brake 100 is quickly released through the first direct unloading reversing valve 311, so that the first brake is switched on. After the first brake is closed, the second working directional valve 325 is de-energized and the third accumulator 74 stops supplying oil to the second brake. The first working directional valve 322 and the third emergency braking directional valve 328 are powered off, the second direct unloading directional valve 321 is powered on, and hydraulic oil in the second brake 200 is quickly relieved through the second direct unloading directional valve 321, so that the closing of the second brake is realized.

When the power supply of the system fails (the system is completely powered off), emergency braking is automatically switched into. The hydraulic oil in the first brake rapidly drops the pressure to the maximum static unbalance tension through the emergency relief valve 316 and the second emergency braking reversing valve 319, and the winch achieves the half brake. The first emergency braking reversing valve 318 is controlled by using a power-off delay relay, and the pressure of the safety braking system is slowly reduced to 0 through the first emergency speed regulating valve 317 and the first emergency braking reversing valve 318 after delay, so that the winch is slowly and stably braked. When the power is completely lost, a power-loss delay relay is used for controlling the third emergency braking reversing valve 328, so that the second brake is prevented from starting braking when the first brake is half-braked, and after the delay, the pressure of the second brake system is slowly reduced to 0 through the second emergency speed regulating valve 327 and the third emergency braking reversing valve 328, so that the second brake is switched on.

The foregoing description of the preferred embodiments of the present disclosure is provided for the purpose of illustration only, and is not intended to limit the disclosure to the particular embodiments disclosed, but on the contrary, the intention is to cover all modifications, equivalents, alternatives, and alternatives falling within the spirit and principles of the disclosure.

Claims (10)

1. A hydraulic control system of a winch brake is characterized by comprising a power unit (1), an oil inlet unit (2) and an oil return unit (3),

The oil inlet unit (2) is communicated with the power unit (1) and is used for controlling pressure oil from the power unit (1) to enter one of a first brake (100) and a second brake (200), the first brake (100) is used for carrying out emergency braking on the winch when the winch encounters accidents, and the second brake (200) is used for carrying out braking on the winch when the winch works;

The oil return unit (3) is respectively communicated with the first brake (100) and the second brake (200), and the oil return unit (3) is used for selectively guiding pressure oil in the first brake (100) and the second brake (200) into an oil tank.

2. The hydraulic control system according to claim 1, wherein the oil inlet unit (2) comprises a first electromagnetic two-way directional valve (21), a second electromagnetic two-way directional valve (22) and a third electromagnetic two-way directional valve (23), an oil inlet of the first electromagnetic two-way directional valve (21) is communicated with an oil inlet of the power unit (1), a first oil inlet of the first electromagnetic two-way directional valve (21) is communicated with an oil inlet of the second electromagnetic two-way directional valve (22), a second oil inlet of the first electromagnetic two-way directional valve (21) is communicated with an oil inlet of the third electromagnetic two-way directional valve (23),

An oil outlet of the second electromagnetic two-position reversing valve (22) is communicated with the first brake (100), and an oil outlet of the third electromagnetic two-position reversing valve (23) is communicated with the second brake (200).

3. The hydraulic control system according to claim 1, characterized in that the oil return unit (3) comprises a first oil return valve group (31) and a second oil return valve group (32);

the first oil return valve group (31) comprises a first oil return reversing valve (310), a first direct unloading reversing valve (311), a constant speed reducing reversing valve (312) and a constant speed reducing overflow valve (313),

An oil inlet of the first oil return reversing valve (310) is communicated with the first brake (100), an oil outlet of the first oil return reversing valve (310) is respectively communicated with an oil inlet of the first direct unloading reversing valve (311) and an oil inlet of the constant speed reducing overflow valve (313), an oil return port of the first direct unloading reversing valve (311) is communicated with the oil tank, an oil outlet of the constant speed reducing overflow valve (313) is communicated with an oil inlet of the constant speed reducing reversing valve (312), a control oil port of the constant speed reducing overflow valve (313) is communicated with an oil inlet of the constant speed reducing reversing valve, and an oil return port of the constant speed reducing reversing valve (312) is communicated with the oil tank;

the second oil return valve group (32) comprises a second oil return reversing valve (320), a second direct unloading reversing valve (321), a first working reversing valve (322) and a first working overflow valve (323), an oil inlet of the second oil return reversing valve (320) is communicated with the second brake (200), an oil outlet of the second oil return reversing valve (320) is respectively communicated with an oil inlet of the second direct unloading reversing valve (321) and the first working overflow valve (323), an oil return port of the second direct unloading reversing valve (321) is communicated with the oil tank, an oil outlet of the first working overflow valve (323) is communicated with an oil inlet of the first working reversing valve (322), a control oil port of the first working overflow valve (323) is communicated with an oil inlet of the first working reversing valve (322), and an oil return port of the first working reversing valve (322) is communicated with the oil tank.

4. A hydraulic control system according to claim 3, characterized in that the first oil return valve block (31) further comprises a constant torque reversing valve (314) and a constant torque relief valve (315), the oil inlet of the constant torque relief valve (315) being in communication with the oil outlet of the first oil return reversing valve (310), the oil outlet of the constant torque relief valve (315) being in communication with the oil inlet of the constant torque reversing valve (314), the control oil port of the constant torque relief valve (315) being in communication with its own oil inlet;

the oil return port of the constant torque reversing valve (314) is communicated with the oil tank.

5. The hydraulic control system according to claim 3, characterized in that the first oil return valve group (31) further comprises an emergency relief valve (316), a first emergency speed valve (317), a first emergency brake directional valve (318) and a second emergency brake directional valve (319), an oil inlet of the emergency relief valve (316) is in communication with an oil outlet of the first oil return directional valve (310), an oil outlet of the emergency relief valve (316) is in communication with an oil inlet of the first emergency brake directional valve (318), an oil return port of the first emergency brake directional valve (318) is in communication with the oil tank, an oil inlet of the first emergency speed valve (317) is in communication with an oil outlet of the first oil return directional valve (310) and an oil inlet of the emergency relief valve (316), an oil outlet of the first emergency speed valve (317) is in communication with an oil inlet of the second emergency brake directional valve (319), an oil outlet of the second emergency brake directional valve (319) is in communication with an oil inlet of the first emergency brake directional valve (318), and the second emergency brake directional valve (319) is in communication with the first directional valve (318).

6. A hydraulic control system according to claim 3, characterized in that the second oil return valve group (32) further comprises a second working directional valve (325) and a second working relief valve (326), wherein the oil inlet of the second working relief valve (326) is communicated with the oil outlet of the second oil return directional valve (320), the oil outlet of the second working relief valve (326) is communicated with the oil inlet of the second working directional valve (325), the control oil port of the second working relief valve (326) is communicated with the oil inlet of the second working relief valve (326), and the oil return port of the second working directional valve (325) is communicated with the oil tank.

7. A hydraulic control system according to claim 3, characterized in that the second oil return valve group (32) further comprises a second emergency speed valve (327) and a third emergency braking reversing valve (328), the oil inlet of the second emergency speed valve (327) being in communication with the oil outlet of the second oil return reversing valve (320), the oil outlet of the second emergency speed valve (327) being in communication with the oil inlet of the third emergency braking reversing valve (328), the oil return of the third emergency braking reversing valve (328) being in communication with the oil tank.

8. The hydraulic control system according to claim 2, further comprising a first energy charging unit (4) and a second energy charging unit (5) which are identical in structure, wherein the first energy charging unit (4) and the second energy charging unit (5) are mutually connected in parallel and are both connected between the first electromagnetic two-position reversing valve (21) and the second electromagnetic two-position reversing valve (22), and the first energy charging unit (4) comprises a first energy charging one-way valve (41), a first energy charging reversing valve (42), a first energy charging speed valve (43), a first energy accumulator (44) and a first energy charging safety valve (45);

The oil inlet of the first energy-charging one-way valve (41) is communicated with a first oil port of the first electromagnetic two-position reversing valve (21), the oil outlet of the first energy-charging one-way valve (41) is communicated with the first energy accumulator (44), the oil inlet of the first energy-charging reversing valve (42) is communicated with a first oil port of the first electromagnetic two-position reversing valve (21), the oil outlet of the first energy-charging reversing valve (42) is communicated with an oil inlet of the first energy-charging speed regulating valve (43), the oil outlet of the first energy-charging speed regulating valve (43) is communicated with the first energy accumulator (44), the oil inlet of the first energy-charging safety valve (45) is communicated with an oil outlet of the first energy-charging speed regulating valve (43), and the oil return port of the first energy-charging safety valve (45) is communicated with the oil tank, and the control oil port of the first energy-charging safety valve (45) is communicated with the oil inlet of the first energy-charging safety valve.

9. The hydraulic control system according to claim 8, further comprising a third charging unit (7), wherein the third charging unit (7) is connected between the first electromagnetic two-position directional valve (21) and the third electromagnetic two-position directional valve (23), and wherein the third charging unit (7) has the same structure as the first charging unit (4).

10. The hydraulic control system according to any one of claims 1-9, characterized in that the power unit (1) comprises a driving pump (11), a power overflow valve (12) and a power reversing valve (13), an oil suction port of the driving pump (11) is communicated with the oil tank, a pressure oil port of the driving pump (11) is communicated with an oil inlet of the power overflow valve (12), an oil outlet of the power overflow valve (12) is communicated with the oil tank, a control oil port of the power overflow valve (12) is communicated with an oil inlet of the power overflow valve, a spring cavity of the power overflow valve (12) is communicated with an oil inlet of the power reversing valve (13), and an oil return port of the power reversing valve (13) is communicated with the oil tank.