Constant-tension hydraulic device for preventing grab bucket from rotating

Abstract

The utility model discloses a constant-tension hydraulic device for preventing a grab bucket from rotating. The constant-tension hydraulic device comprises a hydraulic pump, a control valve group and a hoisting mechanism, the control valve group comprises an oil inlet one-way valve, an oil return one-way valve, an electromagnetic directional valve, a shuttle valve and an overflow valve; the hoisting mechanism comprises a hydraulic motor, a brake, a speed reducer, a winding drum and a steel wire rope; hydraulic oil ports of the hydraulic pump, the control valve bank and the hoisting mechanism are connected through hydraulic pipelines, an oil outlet of the hydraulic pump is connected with a port P of the control valve bank, a port T of the control valve bank is connected with return oil, a port C of the control valve bank is connected with a port Br of the hoisting mechanism, a port A and a port B of the control valve bank are correspondingly connected with a port A and a port B of the hoisting mechanism, and a port Dr of the hoisting mechanism is connected with the return oil. By utilizing the characteristics of a hydraulic system and elements, the steel wire rope is connected with the grab bucket, and certain constant tension is ensured, so that unnecessary swing and rotation of the grab bucket are prevented, and the engineering problem is solved.

Description

Technical Field

[0001] The utility model belongs to the technical field of engineering crane components and relates to a constant tension hydraulic device for preventing a grab bucket from rotating. Background Art

[0002] Grab bucket is a very important application of construction cranes and is widely used in ports, rivers, railways, factories and other application scenarios that require dredging, excavation and material handling. However, during the operation of the grab bucket, affected by external conditions such as dynamic load and wind load, the grab bucket itself will rotate and shake to varying degrees, affecting the realization of the grab bucket function and work efficiency. Utility Model Content

[0003] The utility model aims to provide a constant tension hydraulic device for preventing grab bucket from rotating, which is installed on an engineering crane and has strong adaptability, controllable cost and easy assembly, and provides a constant tension for the crane grab bucket in the lateral direction, so that the grab bucket remains stable during operation and prevents swinging and rotation.

[0004] The scheme adopted by the utility model is: the device includes a hydraulic pump, a control valve group and a hoisting mechanism; its characteristics are: the control valve group includes an oil inlet check valve, an oil return check valve, an electromagnetic reversing valve, a shuttle valve and an overflow valve; the hoisting mechanism includes a hydraulic motor, a brake, a reducer, a drum and a wire rope; the hydraulic pump, the control valve group and each hydraulic oil port of the hoisting mechanism are connected through a hydraulic pipeline, wherein: the oil outlet of the hydraulic pump is connected to the P port of the control valve group, the T port of the control valve group is connected to the return oil, the C port of the control valve group is connected to the Br port of the hoisting mechanism, the A port and the B port of the control valve group are correspondingly connected to the A port and the B port of the hoisting mechanism, and the Dr port of the hoisting mechanism is connected to the return oil.

[0005] When in use, the utility model is installed on a crane body with a grab bucket function. When the other end of the wire rope wound on the drum needs to be connected to the grab bucket body, the hydraulic device drives the drum to release the wire rope. When the grab bucket reciprocates up and down, the utility model switches to a constant tension mode, and the wire rope is actively tightened and passively released along with the grab bucket, and a constant tension is maintained on the grab bucket in the lateral and oblique directions.

[0006] The utility model utilizes the characteristics of hydraulic system and components to connect the wire rope with the grab bucket and ensure a certain constant tension, thus preventing the grab bucket from swinging and rotating unnecessarily and solving engineering problems. It has many advantages such as modular structure, high integration, easy installation and modification, self-adjustable parameters to meet the requirements of different situations, and economical and controllable cost, etc. It fills the gap of such devices and deserves wide promotion and application. BRIEF DESCRIPTION OF THE DRAWINGS

[0007] Figure 1 It is a structural schematic diagram of the utility model;

[0008] Figure 2 This is a working state diagram of the winch mechanism of the utility model when actively releasing the rope;

[0009] Figure 3 This is a working state diagram of the winch mechanism of the utility model when actively collecting the rope;

[0010] Figure 4 This is a working state diagram of the winch mechanism of the utility model when the rope is passively released.

[0011] In the figure: 1-hydraulic pump; 2-control valve group; 2.1-oil inlet check valve; 2.2-oil return check valve; 2.3-electromagnetic reversing valve; 2.4-shuttle valve; 2.5-overflow valve; 3-winch mechanism; 3.1-hydraulic motor; 3.2-brake; 3.3-reducer; 3.4-drum; 3.5-wire rope. DETAILED DESCRIPTION

[0012] The utility model comprises a hydraulic pump 1, a control valve group 2 and a hoisting mechanism 3. The control valve group 2 is an integrated valve group, which comprises an oil inlet check valve 2.1, an oil return check valve 2.2, an electromagnetic reversing valve 2.3, a shuttle valve 2.4 and an overflow valve 2.5. The hoisting mechanism 3 comprises a hydraulic motor 3.1, a brake 3.2, a reducer 3.3, a drum 3.4 and a wire rope 3.5. The hydraulic oil ports of the hydraulic pump 1, the control valve group 2 and the hoisting mechanism 3 are connected through a hydraulic pipeline, wherein: the oil outlet of the hydraulic pump 1 is connected to the P port of the control valve group 2, the T port of the control valve group 2 is connected to the return oil, the C port of the control valve group 2 is connected to the Br port of the hoisting mechanism 3, the A port and the B port of the control valve group 2 are correspondingly connected to the A port and the B port of the hoisting mechanism 3, and the Dr port of the hoisting mechanism 3 is connected to the return oil.

[0013] The hydraulic motor 3.1 is mechanically connected to the input end of the reducer 3.3, and the output end of the reducer 3.3 is mechanically connected to the drum 3.4. The torque of the hydraulic motor 3.1 and the tension of the wire rope 3.5 interact with each other.

[0014] The oil inlet non-return valve 2.1 in the control valve group 2 can ensure the rigidity of the system and pipelines, and the oil does not flow back; the oil return non-return valve 2.2 is used as a system back pressure valve to ensure that the hydraulic motor 3.1 does not suck air when replenishing oil in the reverse direction under pump working conditions; the electromagnetic reversing valve 2.3 is a three-position four-way electromagnetic reversing valve, and the two energized working positions correspond to the two modes of active rope release and constant tension of the drum respectively; the shuttle valve 2.4 supplies the working oil circuit of the AB chamber to the brake oil circuit of the winch mechanism 3 through the C port; the set pressure of the overflow valve 2.5 determines the system static oil pressure of the hydraulic system and thus determines the constant tension of the wire rope.

[0015] like Figure 2As shown, when the utility model is assembled for the first time, the electromagnetic reversing valve 2.3 electromagnet a is powered, and the hydraulic pump 1 outputs hydraulic oil through the P oil port of the control valve group 2, the oil inlet check valve 2.1, the electromagnetic reversing valve 2.3, the A oil port of the control valve group 2, the A oil port of the hydraulic motor 3.1, the B oil port of the hydraulic motor 3.1, the B oil port of the control valve group 2, the electromagnetic reversing valve 2.3, the return oil check valve 2.2, and the T oil port of the control valve group 2. At the same time, the working oil opens the brake 3.2 through the shuttle valve 2.4, the control valve group 2, the C oil port, and the Br oil port of the winch mechanism 3, and the hydraulic motor 3.1 drives the reducer 3.3 and the drum 3.4 to rotate in the direction of releasing the rope, and the wire rope 3.5 is released and connected to the grab. When the winch mechanism is required to work in the constant tension mode, it is necessary to power the electromagnetic reversing valve 2.3 electromagnet b.

[0016] like Figure 3 As shown, when the grab bucket is in the process of tightening the wire rope 3.5, the hydraulic pump 1 outputs hydraulic oil through the P oil port of the control valve group 2, the oil inlet check valve 2.1, the electromagnetic reversing valve 2.3, the B oil port of the control valve group 2, the B oil port of the hydraulic motor 3.1, the A oil port of the hydraulic motor 3.1, the A oil port of the control valve group 2, the electromagnetic reversing valve 2.3, the return oil check valve 2.2, and the T oil port of the control valve group 2. At the same time, the working oil opens the brake 3.2 through the shuttle valve 2.4, the C oil port of the control valve group 2, and the Br oil port of the winch mechanism 3, and the hydraulic motor 3.1 drives the reducer 3.3 and the drum 3.4 to rotate in the direction of rope collection. It is worth noting that no matter how fast the grab bucket runs, the flow output by the hydraulic pump 1 can always ensure that the drum 3.4 can tighten the wire rope 3.5. Therefore, the excess flow in the system can overflow through the overflow valve 2.5. This overflow pressure determines the working pressure of the hydraulic system, thereby determining the output torque of the motor and reducer, and the tension of the wire rope 3.5 when it is wound.

[0017] like Figure 4 As shown, when the grab bucket is in the process of releasing the wire rope 3.5, the tension will drive the drum 3.4, the reducer 3.3 and the hydraulic motor 3.1 to rotate in the direction of releasing the rope through the wire rope 3.5. At this time, the working state of the hydraulic motor 3.1 belongs to the "pump working condition". The hydraulic oil returns to the control valve group 2 through the B oil port, and overflows through the overflow valve 2.5 together with the oil coming from the direction of the hydraulic pump 1. This overflow pressure still determines the tension of the wire rope 3.5. The hydraulic oil after the overflow of the overflow valve 2.5 produces a liquid resistance effect due to the electromagnetic reversing valve 2.3 and the return oil check valve 2.2 on the return oil line. A part of the hydraulic oil will be supplemented from the A oil port of the control valve group 1 to the A oil port of the hydraulic motor 3.1, thereby ensuring that the motor is adequately supplied with oil under the "pump working condition". The oil circuit for opening the brake 3.2 is the same.

[0018] The overflow pressure of the overflow valve 2.5 in the control valve group 2 can be adjusted at any time according to the needs of different tensions during use, and the adjustment method can be manual or remote electrical control.

[0019] The brake 3.2 can be opened by using the working oil through the shuttle valve 2.4 or by taking it from an external oil circuit.

Claims

1. A constant tension hydraulic device for preventing a grab bucket from rotating, comprising a hydraulic pump (1), a control valve group (2) and a hoisting mechanism (3); wherein: The control valve group (2) comprises an oil inlet check valve (2.1), an oil return check valve (2.2), an electromagnetic reversing valve (2.3), a shuttle valve (2.4) and an overflow valve (2.5); the hoisting mechanism (3) comprises a hydraulic motor (3.1), a brake (3.2), a reducer (3.3), a drum (3.4) and a wire rope (3.5); the hydraulic oil ports of the hydraulic pump (1), the control valve group (2) and the hoisting mechanism (3) are connected through a hydraulic pipeline, wherein: the oil outlet of the hydraulic pump (1) is connected to the P port of the control valve group (2), the T port of the control valve group (2) is connected to the return oil, the C port of the control valve group (2) is connected to the Br port of the hoisting mechanism (3), the A port and the B port of the control valve group (2) are connected to the A port and the B port of the hoisting mechanism (3) respectively, and the Dr port of the hoisting mechanism (3) is connected to the return oil.

2. A constant tension hydraulic device for preventing grab bucket rotation according to claim 1, characterized in that: The hydraulic motor (3.1) is mechanically connected to the input end of the reducer (3.3); the output end of the reducer (3.3) is mechanically connected to the drum (3.4); the torque of the hydraulic motor (3.1) and the tension of the steel wire rope (3.5) interact with each other.

3. A constant tension hydraulic device for preventing grab bucket from rotating according to claim 1 or 2, characterized in that: The oil inlet check valve (2.1) in the control valve group (2) can ensure the rigidity of the system and the pipeline, and prevent the oil from flowing back; the oil return check valve (2.2) is used as a system back pressure valve to ensure that the hydraulic motor (3.1) does not suck air when the oil is replenished in the reverse direction under pump working conditions; the electromagnetic reversing valve (2.3) is a three-position four-way electromagnetic reversing valve, and the two energized working positions correspond to the two modes of active rope release and constant tension of the drum respectively; the shuttle valve (2.4) supplies the working oil circuit of the AB chamber to the brake oil circuit of the winch mechanism (3) through the C port; the set pressure of the overflow valve (2.5) determines the system static oil pressure of the hydraulic system, thereby determining the constant tension of the wire rope.

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