Wave compensation crane ship landing hydraulic control system

Abstract

The invention provides a wave compensation crane ship landing hydraulic control system which comprises a fast loop and a slow-speed loop, and the fast loop sequentially comprises a main pump, an electric control operating valve, a hydraulic control one-way valve, a hydraulic motor and an oil tank in the moving direction of hydraulic oil; the retarding loop sequentially comprises an auxiliary pump, a one-way valve, a hydraulic motor, a balance valve, a two-position two-way electromagnetic reversing valve, a throttling valve, an electric control operating valve and an oil tank in the moving direction of hydraulic oil, the retarding loop further comprises a brake loop, and the brake loop sequentially comprises an auxiliary pump control valve set, a shuttle valve, a pressure reducing valve and a hydraulic control reversing valve in the moving direction of the hydraulic oil. The main pump and the auxiliary pump are coaxially connected, so that the descending and slow descending actions of the winch are achieved, oil is independently supplied through the small-flow pump, and the slow descending speed is accurately adjusted through the small-flow throttling valve.

Description

Technical Field

[0001] This invention relates to a wave-compensated crane hydraulic control system for launching a ship. Background Technology

[0002] To ensure the smooth and safe placement of certain special cargoes onto the supply ship, hydraulic rotary cranes equipped with wave compensation functions require that the hydraulic winch hook of the supply ship crane be lowered to a very slow landing speed when it approaches the deck of the supply ship. This landing speed is sometimes required to be one-twentieth of the normal lowering speed.

[0003] To meet this requirement for large-tonnage wave-compensated cranes, the following two technical challenges need to be addressed: Since the lifting and lowering speed of the crane winch is controlled by manually or electronically adjusting the opening of the main valve core of the control valve to regulate the flow of hydraulic oil into the winch hydraulic motor, the main valve core of the control valve must meet the requirements of high flow rate during rapid descent while also ensuring precise adjustment capability for low flow rate. This places high demands on the manufacturing process of the control valve, and ordinary control valves are unlikely to meet this requirement.

[0004] For the hydraulic pump in the hydraulic control system of the crane, in order to ensure the rapid response performance of wave compensation control, the hydraulic pump adopts a large displacement constant pressure variable control. When the hydraulic winch is lowered quickly, the hydraulic pump outputs a large flow. When the winch approaches the deck and is lowered at the landing speed, the required flow is very small. At this time, if the pump displacement does not change in time, most of the flow will overflow under high pressure through the relief valve, which will cause the hydraulic system to overheat abnormally. In addition, if the control performance of the pump's variable mechanism is not good at small displacement, it will cause the pump's small flow output to be unstable, causing the winch to vibrate during lowering.

[0005] Therefore, a wave-compensated hydraulic control system for lowering a crane is needed to solve the problem that the hydraulic winch control valve of the supply ship crane in the existing technology cannot meet the precise adjustment capability for small flow and the pump has unstable output at small flow, which causes the winch to vibrate during lowering. Summary of the Invention

[0006] The purpose of this invention is to overcome the shortcomings of the prior art and provide a wave-compensated crane ship-landing hydraulic control system. This system achieves the slow descent of the winch by supplying oil separately with a small-flow pump and by precisely adjusting the slow descent speed with a small-flow throttle valve. This objective is achieved as follows:

[0007] This invention proposes a wave-compensated crane landing hydraulic control system, comprising a fast circuit and a slow circuit. The fast circuit, along the hydraulic oil movement direction, sequentially includes: a main pump, an electrically controlled valve, a hydraulically controlled check valve, a hydraulic motor, and an oil tank. The slow circuit, along the hydraulic oil movement direction, sequentially includes: an auxiliary pump, a check valve, a hydraulic motor, a balance valve, a two-position two-way solenoid directional valve, a throttle valve, an electrically controlled valve, and an oil tank. The slow circuit also includes a brake circuit, which, along the hydraulic oil movement direction, sequentially includes: an auxiliary pump control valve group, a shuttle valve, a pressure reducing valve, and a hydraulically controlled directional valve. The main pump and the auxiliary pump are coaxially connected.

[0008] Furthermore, both the main pump and the auxiliary pump are connected to an oil tank upstream.

[0009] Furthermore, when the crane winch is in fast mode, the fast circuit is activated; when the crane winch is in slow mode, the electrical control valve is de-circuited, and the slow circuit is activated.

[0010] Furthermore, the hydraulically controlled directional valve is connected to the preset brake of the crane winch to control the activation of the preset brake in a slow-speed state.

[0011] Furthermore, the maximum output flow rate of the auxiliary pump is one-twentieth that of the main pump.

[0012] Compared with the prior art, the beneficial effects of the present invention are: the slow descent action of the winch is supplied with oil by a small flow pump, so there is no need to worry about the abnormal heat generation and stability problems of the large flow pump; since the output flow of the small pump is small, the slow descent speed can be precisely adjusted by a small flow throttle valve that matches its flow, and the fine-tuning performance requirements of the main control valve are not high. Attached Figure Description

[0013] Figure 1 This is a schematic diagram of the hydraulic pipeline of a wave-compensated crane's ship-landing hydraulic control system;

[0014] In the diagram: 1. Main pump, 2. Auxiliary pump, 3. Auxiliary pump control valve group, 4. Control valve, 5. Hydraulic check valve, 6. Throttle valve, 7. Two-position two-way solenoid directional valve, 8. Balance valve, 9. Hydraulic motor, 10. Hydraulic directional valve, 11. Pressure reducing valve, 12. Shuttle valve, 13. Check valve. Detailed Implementation

[0015] To enhance understanding of the present invention, the present invention will be further described in detail below with reference to embodiments and accompanying drawings. These embodiments are only used to explain the present invention and do not constitute a limitation on the scope of protection of the present invention.

[0016] Example 1

[0017] Please refer to Figure 1The present invention provides a wave-compensated crane landing hydraulic control system, including a fast circuit and a slow circuit. The fast circuit includes, in sequence along the hydraulic oil movement direction: a main pump 1, an electrically controlled valve 4, a hydraulically controlled check valve 5, a hydraulic motor 9, and an oil tank. The slow circuit includes, in sequence along the hydraulic oil movement direction: an auxiliary pump 2, a check valve 13, a hydraulic motor 9, a balance valve 8, a two-position two-way solenoid directional valve 7, a throttle valve 6, an electrically controlled valve 4, and an oil tank. The slow circuit also includes a brake circuit, which includes, in sequence along the hydraulic oil movement direction: an auxiliary pump control valve group 3, a shuttle valve 12, a pressure reducing valve 11, and a hydraulically controlled directional valve 10. The main pump 1 and the auxiliary pump 2 are coaxially connected.

[0018] In this embodiment, the upstream of both the main pump 1 and the auxiliary pump 2 is an oil tank; when the crane winch is in a fast state, the fast circuit is connected; when the crane winch is in a slow state, the electrically controlled control valve 4 is disconnected and the slow circuit is connected; the hydraulically controlled directional valve 10 is connected to the preset brake of the crane winch to control the preset brake to start in the slow state, and the maximum output flow value of the auxiliary pump 2 is one-twentieth of that of the main pump 1.

[0019] The working principle of this invention is as follows:

[0020] When the crane winch is operating at normal speed, the main pump 1 and the electrically controlled control valve 4 supply oil to the hydraulic motor 9 through the hydraulically controlled check valve 5 on the winch valve assembly, driving the winch to operate at normal speed. The main pump 1 and the auxiliary pump 2 are coaxially connected and driven by the same motor. The outlet of the auxiliary pump 2 is connected to the control valve assembly. When the winch is operating at normal speed, the auxiliary pump 2 does not operate under load, and the output hydraulic oil is directly returned to the oil tank for empty circulation. When the hook of the hydraulic winch of the supply ship crane is lowered close to the deck of the supply ship, the operator presses the slow descent button on the control panel, the control valve 4 is de-energized, and the solenoid valve of the auxiliary pump control valve assembly 3 and the two-position two-way solenoid valve integrated in the winch valve assembly are activated. When powered on, the main pump 1 switches to no-load standby mode, and the auxiliary pump 2 switches to load operation. The oil output from the auxiliary pump 2 enters the winch valve group after passing through the control valve group. Within the winch valve group, it is divided into two paths. One path enters the lowering oil port of the winch motor through the one-way valve 13. The return oil from the motor returns to the oil tank through the solenoid reversing valve and the throttle valve 6. The other path opens the winch brake through the shuttle valve 12, the pressure reducing valve 11, and the hydraulic reversing valve 10, and the winch begins to slowly descend. Since the maximum output flow rate of the auxiliary pump 2 is only one-twentieth of that of the main pump 1, and the lowering speed can be further fine-tuned through the throttle valve 6, the slow descent of the winch can be achieved.

[0021] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention and are not intended to limit it. Although the present invention has been described in detail with reference to preferred embodiments, those skilled in the art should understand that modifications or equivalent substitutions can be made to the technical solutions of the present invention without departing from the spirit and scope of the technical solutions of the present invention, and all such modifications or substitutions should be covered within the scope of the claims of the present invention.

Claims

1. A wave-compensated crane ship-landing hydraulic control system, characterized in that, The system includes a fast circuit and a slow circuit. The fast circuit, along the direction of hydraulic oil movement, includes, in sequence: a main pump, an electrically controlled valve, a hydraulically controlled check valve, a hydraulic motor, and an oil tank. The slow circuit, along the direction of hydraulic oil movement, includes, in sequence: an auxiliary pump, a check valve, a hydraulic motor, a balance valve, a two-position two-way solenoid directional valve, a throttle valve, an electrically controlled valve, and an oil tank. The slow circuit also includes a brake circuit, which, along the direction of hydraulic oil movement, includes, in sequence: an auxiliary pump control valve group, a shuttle valve, a pressure reducing valve, and a hydraulically controlled directional valve. The main pump and the auxiliary pump are coaxially connected.

2. The wave-compensated crane ship-landing hydraulic control system according to claim 1, characterized in that, Both the main pump and the auxiliary pump have an oil tank upstream.

3. The wave-compensated crane ship-landing hydraulic control system according to claim 1, characterized in that, When the crane winch is in fast mode, the fast circuit is activated; when the crane winch is in slow mode, the electrical control valve is de-circuited, and the slow circuit is activated.

4. The wave-compensated crane ship-landing hydraulic control system according to claim 3, characterized in that, The hydraulically controlled directional valve is connected to the preset brake of the crane winch to control the preset brake to start in a slow-speed state.

5. The wave-compensated crane ship-landing hydraulic control system according to claim 4, characterized in that, The maximum output flow rate of the auxiliary pump is one-twentieth that of the main pump.

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