Bidirectional braking system for backhoe loader

Abstract

The bidirectional braking system comprises a gearbox, a loading brake valve and a brake, the gearbox supplies oil to the loading brake valve and an excavation brake valve, the two brake valves are both communicated with the brake through a selector valve, and the selector valve is communicated with the brake. Two different operation ends of the backhoe loader are respectively provided with a control device for controlling whether the two brake valves are conducted or not; when the backhoe loader is in loading operation, the selection valve conducts the loading brake valve and the brake, and when the backhoe loader is in excavating operation, the selection valve conducts the excavating brake valve and the brake; the bidirectional braking device can realize bidirectional braking of the backhoe loader during excavation end operation and loading end operation.

Description

Technical Field

[0001] The invention relates to an excavator loader, in particular to a bidirectional braking system for the excavator loader. Background Art

[0002] As a multifunctional engineering machinery, the backhoe loader is widely used in domestic and foreign markets due to its flexible maneuverability. At present, the mainstream backhoe loaders on the market can only achieve one-way driving and braking, that is, facing the loading end. However, in some specific working environments and conditions, sometimes when working facing the excavation end, it is often necessary to move the machine frequently to adjust the working posture, such as: excavation of ditches, pipelines, etc. At this time, conventional backhoe loaders show certain limitations, and the operating movements when moving the machine are complicated and inefficient. Although some backhoe loaders have achieved the driving function when facing the excavation end, they do not have the braking function, which poses certain safety hazards. Summary of the invention

[0003] Purpose of the invention: The purpose of the present invention is to provide a bidirectional braking system for an excavator loader that realizes bidirectional braking for excavation end operations and loading end operations.

[0004] Technical solution: The two-way braking system for an excavator loader described in the present invention includes a gearbox, a loading brake valve and a brake. The gearbox supplies oil to the loading brake valve and the excavation brake valve. Both brake valves are connected to the brake through a selection valve. Two different working ends of the excavator loader are respectively provided with control devices for controlling whether the two brake valves are turned on. When the excavator loader is in loading operation, the selection valve turns on the loading brake valve and the brake. When the excavator loader is in excavation operation, the selection valve turns on the excavation brake valve and the brake.

[0005] Based on the above technical solution, the gearbox supplies oil to the loading brake valve and the excavation brake valve at the same time, and then the selection valve is switched to control which brake valve is connected to the brake, and the corresponding brake valve is used to control the brake to achieve braking; and the control devices of the two brake valves are arranged at two different working ends of the excavator loader. When corresponding operations need to be performed facing different ends, the brake and the corresponding brake valve can be connected by controlling the valve core of the selection valve. For example, when loading operations are performed facing the loading end, the valve core of the selection valve is controlled to connect the loading brake valve and the brake, and then the control device at the loading end controls whether the loading brake valve is connected to input the brake oil of the gearbox into the brake for braking; the operation facing the excavation end is the same and will not be repeated. Therefore, the two-way braking of the excavator loader can be achieved through this system.

[0006] Preferably, the control device comprises a loading brake pedal and an excavation brake pedal respectively connected to the loading brake valve and the excavation brake valve.

[0007] The control device adopts pedals to facilitate the driver's control.

[0008] Preferably, the selector valve is provided with a selector switch for controlling its reversing direction.

[0009] The selection switch is provided to facilitate the control of the valve core reversing of the selection valve.

[0010] Preferably, the excavation brake valve is a two-position two-way solenoid valve.

[0011] The two-position two-way solenoid valve has a simple structure and can also switch the state of whether the oil circuit is conductive.

[0012] Preferably, the excavation brake pedal is a single-contact switch.

[0013] The excavator brake pedal adopts a single-contact switch. By stepping on the pedal to connect the corresponding circuit, the excavator brake valve core is reversed, thereby realizing the switching of the oil circuit conduction state. Compared with using a pedal to control the valve core reversal through mechanical transmission, the operation is simpler and easier.

[0014] Preferably, the oil return ports of the loading brake valve and the selection valve are communicated with the oil return port of the gearbox.

[0015] The oil return port of the valve is connected to the oil return port of the gearbox so as to recover the brake oil, thereby avoiding obstruction of the valve core switching and avoiding waste of oil.

[0016] Preferably, two brakes are provided.

[0017] The brakes are provided with two so that the two wheels can be controlled independently, and the braking operation can be performed more flexibly.

[0018] Beneficial effects: Compared with the prior art, the present invention has the following significant effects: oil is supplied to the loading brake valve and the excavation brake valve through the gearbox, and then the selection valve controls which brake valve is connected to the brake. Each brake also has a corresponding control device at a different working end of the excavator loader, which enables the excavator loader to perform braking operations independently at different working ends, that is, two-way braking. BRIEF DESCRIPTION OF THE DRAWINGS

[0019] Figure 1 This is a schematic diagram of the overall structure of this system. DETAILED DESCRIPTION

[0020] As shown in the figure, a bidirectional braking system for an excavator loader described in the present invention includes a gearbox 1, a loading brake valve 2 and a brake 3, the gearbox 1 supplies oil to the loading brake valve 2 and the excavation brake valve 4, both brake valves are connected to the brake 3 through a selection valve 5, and two different working ends of the excavator loader are respectively provided with a control device for controlling whether the two brake valves are connected; when the excavator loader is in loading operation, the selection valve 5 connects the loading brake valve 2 and the brake 3, and when the excavator loader is in excavation operation, the selection valve 5 connects the excavation brake valve 4 and the brake 3.

[0021] The gearbox 1 has a built-in speed pump installed at the flywheel end of the engine. The speed pump is driven by the engine to pressurize the lubricating oil inside the gearbox, and the brake oil is drawn out from here.

[0022] The loading brake valve 2 is an existing brake valve, which can be a single solenoid valve or a mechanical reversing valve or other valves; for example, the loading brake valve 2 adopts a mechanical two-position four-way valve, whose P port and T port are respectively connected to the oil outlet and oil return port of the gearbox, and the A port and the B port are connected to the oil inlet of the selection valve 5. In the normal position, the P port is connected to the A port and the B port, and the T port is blocked. After reversing, the P port is blocked, and the T port is connected to the A port and the B port. That is, in the normal position, the brake oil output by the gearbox 1 is conducted to the selection valve 5, and after reversing, the brake oil of the gearbox 1 is blocked from being delivered to the selection valve 5; at the loading end, that is, the front end of the excavator loader, a loading brake pedal 6 for controlling the loading brake valve 2 is provided, and after stepping on the loading brake pedal 6, the valve core of the loading brake valve 2 can be pushed to reverse.

[0023] The brake 3 is arranged in the drive axle, and the brake oil pushes the piston rod of the oil cylinder inside the brake 3 to move, driving the brake friction plate to contact / disengage, thereby achieving braking and brake release. A brake 3 can be set for each wheel on both sides of the drive axle.

[0024] The excavation brake valve 4 can adopt the same structure as the loading brake valve 2, or it can be different. For example, the simplest two-position two-way solenoid valve is adopted, and the oil inlet and oil outlet are respectively connected with the oil outlet of the gearbox 1 and the oil inlet of the selection valve 5. When in the normal position, the oil inlet and oil outlet of the excavation brake valve 4 are blocked, and after reversing, the oil inlet and oil outlet are connected; the excavation loader is provided with an excavation brake pedal 7 for controlling the excavation brake valve 4 at the excavation end, that is, the rear end. When the excavation brake valve 4 adopts a solenoid valve, the excavation brake pedal 7 can adopt a single-contact switch. After stepping on the excavation brake pedal 7, the corresponding circuit can be connected to reverse the valve core of the excavation brake valve 4.

[0025] When two brakes 3 are provided, the selection valve 5 is a two-position six-way valve, whose oil inlets are C1, C2, C3 and C4 respectively, and the oil outlets are P1 and P2 respectively, wherein C1 and C4 are connected with the oil outlet of the excavation brake valve 4, C2 and C3 are connected with the oil outlet of the loading brake valve 2, P1 and P2 are connected with the oil inlets of the two brakes 3 respectively, and the selection valve 5 is also provided with an oil return port L connected with the oil return port of the gearbox 1; when the selection valve 5 is in the normal position, the C2 port is connected with the P2 port, the C3 port is connected with the P1 port, and the C1 and C4 ports are both blocked, that is, the loading brake valve 2 and the brake 3 are connected; when the selection valve 5 is reversed, the C1 port is connected with the P2 port, the C4 port is connected with the P1 port, and the C2 and C3 ports are both blocked, that is, the excavation brake valve 4 and the brake 3 are connected.

[0026] The selector valve 5 controls the reversing of its valve core through the selector switch 8. The selector switch 8 can adopt a commonly used two-link rocker switch. The selector switch 8 is arranged at a position on the frame that is easily accessible to the driver for easy operation.

Claims

1. A bidirectional braking system for an excavator loader, comprising a gearbox (1), a loading brake valve (2) and a brake (3), characterized in that: The gearbox (1) supplies oil to the loading brake valve (2) and the excavation brake valve (4); the two brake valves are connected to the brake (3) via a selection valve (5); and control devices for controlling whether the two brake valves are connected are respectively provided at two different working ends of the excavation loader; when the excavation loader is in a loading operation, the selection valve (5) connects the loading brake valve (2) and the brake (3); and when the excavation loader is in an excavation operation, the selection valve (5) connects the excavation brake valve (4) and the brake (3).

2. A bidirectional braking system for an excavator loader according to claim 1, characterized in that: The control device comprises a loading brake pedal (6) and an excavation brake pedal (7) which are respectively connected to the loading brake valve (2) and the excavation brake valve (4).

3. A bidirectional braking system for an excavator loader according to claim 1, characterized in that: The selector valve (5) is provided with a selector switch (8) for controlling its switching direction.

4. A bidirectional braking system for an excavator loader according to claim 1, characterized in that: The excavation brake valve (4) is a two-position two-way solenoid valve.

5. A bidirectional braking system for an excavator loader according to claim 2, characterized in that: The excavation brake pedal (7) is a single-contact switch.

6. A bidirectional braking system for an excavator loader according to claim 2, characterized in that: The loading brake pedal (6) and the excavation brake pedal (7) are respectively arranged at the front and rear ends of the excavator loader.

7. A bidirectional braking system for an excavator loader according to claim 1, characterized in that: The oil return ports of the loading brake valve (2) and the selection valve (5) are in communication with the oil return port of the gearbox (1).

8. A bidirectional braking system for an excavator loader according to claim 2, characterized in that: The loading brake valve (2) adopts a mechanical reversing valve, and the reversal of the valve core is controlled by the loading brake pedal (6).

9. A bidirectional braking system for an excavator loader according to claim 1, characterized in that: Two brakes (3) are provided.

10. A bidirectional braking system for an excavator loader according to claim 8, characterized in that: The selection valve (5) is a two-position six-way valve.

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