Bidirectional braking system for excavator loader

Abstract

This invention discloses a bidirectional braking system for a backhoe loader, comprising a gearbox, a loading brake valve, and a brake. The gearbox supplies oil to the loading brake valve and the digging brake valve. Both brake valves are connected to the brake via a selector valve. The backhoe loader has control devices at its two different working ends for controlling whether the two brake valves are open. When the backhoe loader is in loading operation, the selector valve opens the loading brake valve and the brake; when the backhoe loader is in digging operation, the selector valve opens the digging brake valve and the brake. This device enables bidirectional braking of the backhoe loader during both digging and loading operations.

Description

Technical Field

[0001] This invention relates to backhoe loaders, and more particularly to a bidirectional braking system for backhoe loaders. Background Technology

[0002] Backhoe loaders, as multi-functional construction machinery, are widely used in domestic and international markets due to their flexible maneuverability. Currently, most mainstream backhoe loaders can only travel and brake in one direction, i.e., facing the loading end. However, in certain working environments and conditions, it is sometimes necessary to frequently move the machine to adjust its working posture when working facing the excavation end, such as in trench or pipeline excavation. In these situations, conventional backhoe loaders exhibit certain limitations; the maneuvering actions are complex and inefficient. While some backhoe loaders do achieve the function of traveling facing the excavation end, they lack braking capabilities, posing certain safety hazards. Summary of the Invention

[0003] Purpose of the invention: The purpose of this invention is to provide a bidirectional braking system for a backhoe loader that enables bidirectional braking for both excavation and loading operations.

[0004] Technical solution: The bidirectional braking system for a backhoe loader according to the present invention includes a gearbox, a loading brake valve, and a brake. The gearbox supplies oil to the loading brake valve and the digging brake valve. Both brake valves are connected to the brake via a selector valve. The two different working ends of the backhoe loader are respectively equipped with control devices for controlling whether the two brake valves are open. When the backhoe loader is in loading operation, the selector valve opens the loading brake valve and the brake. When the backhoe loader is in digging operation, the selector valve opens the digging brake valve and the brake.

[0005] Based on the above technical solution, the transmission simultaneously supplies oil to both the loading brake valve and the digging brake valve. The selector valve controls which brake valve connects to the brake, and the corresponding brake valve then controls the brake to achieve braking. The control devices for the two brake valves are located at two different working ends of the backhoe loader. When corresponding operations need to be performed facing different ends, the valve core of the selector valve can be controlled to connect the brake to the corresponding brake valve. For example, when performing loading operations facing the loading end, the valve core of the selector valve is controlled to connect the loading brake valve to the brake. Then, the control device at the loading end controls whether the loading brake valve is open to supply brake oil from the transmission to the brake for braking. The operation facing the digging end is similar and will not be elaborated further. Therefore, this system enables bidirectional braking of the backhoe loader.

[0006] Preferably, the control device includes a loading brake pedal and a digging brake pedal respectively connected to the loading brake valve and the digging brake valve.

[0007] The control device uses a pedal for easy driver control.

[0008] Preferably, the selector valve is provided with a selector switch to control its reversal.

[0009] The selection switch facilitates the control of the valve core reversal 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 switch between whether the oil circuit is open or closed.

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

[0013] The excavator brake pedal uses a single-contact switch. Stepping on the pedal connects the corresponding circuit, causing the excavator brake valve spool to switch, thus switching the oil circuit conduction state. Compared to using a pedal to control the valve spool switching through mechanical transmission, the operation is simpler and easier.

[0014] Preferably, the return ports of the loading brake valve and the selector valve are connected to the return port of the gearbox.

[0015] The valve's return port is connected to the gearbox's return port, which allows for the recovery of brake fluid, thus preventing both obstruction of valve core reversal and oil waste.

[0016] Preferably, two brakes are provided.

[0017] The brakes are configured with two units that can control each wheel independently, allowing for more flexible braking operations.

[0018] Beneficial effects: Compared with the prior art, the significant effect of this invention is that: by supplying oil to the loading brake valve and the digging brake valve through the gearbox, and then controlling which brake valve is connected to the brake by the selector valve, and each brake also has a corresponding control device at different working ends of the excavator loader, the excavator loader can perform braking operation independently at different working ends, that is, bidirectional braking. Attached Figure Description

[0019] Figure 1 This is a schematic diagram of the overall structure of the system. Detailed Implementation

[0020] As shown in the figure, the bidirectional braking system for a backhoe loader according to 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 digging brake valve 4. Both brake valves are connected to the brake 3 through a selector valve 5. The two different working ends of the backhoe loader are respectively equipped with control devices for controlling whether the two brake valves are open. When the backhoe loader is in loading operation, the selector valve 5 opens the loading brake valve 2 and the brake 3. When the backhoe loader is in digging operation, the selector valve 5 opens the digging brake valve 4 and the brake 3.

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

[0022] The loading brake valve 2 is an existing brake valve, which can be a single solenoid valve, a mechanical reversing valve, or other valves. For example, the loading brake valve 2 adopts a mechanical two-position four-way valve, with its P port and T port connected to the oil outlet and return port of the transmission, respectively, and its A port and B port connected to the oil inlet of the selector valve 5. In the normal position, the P port is connected to the A port and 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 B port. That is, in the normal position, the brake oil output from the transmission 1 is connected to the selector valve 5, and after reversing, the brake oil output from the transmission 1 is blocked from being supplied to the selector valve 5. At the loading end, i.e., the front end, of the excavator loader, a loading brake pedal 6 is set to control the loading brake valve 2. Pressing the loading brake pedal 6 can push the valve core of the loading brake valve 2 to reverse.

[0023] The brake 3 is installed inside the drive axle. The brake fluid pushes the piston rod of the internal cylinder of the brake 3 to move, causing the brake friction pads to contact / disengage, thereby realizing braking and brake release. One brake 3 can be installed on each wheel on both sides of the drive axle.

[0024] The digging brake valve 4 can have the same structure as the loading brake valve 2, or it can be different. For example, it can be a simple two-position two-way solenoid valve. The oil inlet and outlet are connected to the oil outlet of the gearbox 1 and the oil inlet of the selector valve 5, respectively. In the normal position, the oil inlet and outlet of the digging brake valve 4 are blocked. After reversing, the oil inlet and outlet are connected. The digging loader is equipped with a digging brake pedal 7 at the digging end, which is the rear end, to control the digging brake valve 4. When the digging brake valve 4 is a solenoid valve, the digging brake pedal 7 can be a single-contact switch. After pressing the digging brake pedal 7, the corresponding circuit can be connected to reverse the valve core of the digging brake valve 4.

[0025] When two brakes 3 are provided, the selector valve 5 is a two-position six-way valve with oil inlets C1, C2, C3 and C4, and oil outlets P1 and P2. C1 and C4 are connected to the oil outlet of the excavating brake valve 4, C2 and C3 are connected to the oil outlet of the loading brake valve 2, and P1 and P2 are connected to the oil inlets of the two brakes 3 respectively. The selector valve 5 also has a return port L connected to the return port of the gearbox 1. When the selector valve 5 is in the normal position, port C2 is connected to port P2, port C3 is connected to port P1, and ports C1 and C4 are blocked, which means that the loading brake valve 2 and the brake 3 are connected. When the selector valve 5 is reversed, port C1 is connected to port P2, port C4 is connected to port P1, and ports C2 and C3 are blocked, which means that the excavating brake valve 4 and the brake 3 are connected.

[0026] Selector valve 5 controls the valve core reversal via selector switch 8. Selector switch 8 can be a commonly used two-way rocker switch. Selector switch 8 is located on the frame in a position easily accessible to the driver for convenient operation.

Claims

1. A two-way braking system for a dragline excavator comprising a gear box (1), a drag brake valve (2) and a brake (3), characterised in that: The gearbox (1) supplies oil to the loading brake valve (2) and the digging brake valve (4). Both brake valves are connected to the brake (3) through the selector valve (5). The two different working ends of the excavator loader are respectively equipped with control devices for controlling whether the two brake valves are connected. When the excavator loader is in loading operation, the selector valve (5) connects the loading brake valve (2) and the brake (3). When the excavator loader is in digging operation, the selector valve (5) connects the digging brake valve (4) and the brake (3). The control device includes a loading brake pedal (6) and a digging brake pedal (7) connected to the loading brake valve (2) and the digging brake valve (4) respectively. The loading brake pedal (6) and the digging brake pedal (7) are respectively located at the front and rear ends of the excavator loader.

2. A two-way braking system for a backhoe loader as claimed in claim 1, wherein: The selector valve (5) is equipped with a selector switch (8) to control its reversal.

3. A two-way braking system for a backhoe loader as claimed in claim 1, wherein: The excavation brake valve (4) is a two-position two-way solenoid valve.

4. A two-way braking system for a backhoe loader as defined in claim 1 wherein: The excavator brake pedal (7) is a single-contact switch.

5. A two-way braking system for a backhoe loader as claimed in claim 1, wherein: The oil return ports of the loading brake valve (2) and the selector valve (5) are connected to the oil return port of the gearbox (1).

6. A two-way braking system for a backhoe loader as defined in claim 1 wherein: The loading brake valve (2) is a mechanical reversing valve whose valve core is controlled by the loading brake pedal (6) to reverse.

7. A two-way braking system for a backhoe loader as claimed in claim 1, wherein: Two brakes (3) are provided.

8. A bidirectional braking system for an excavator loader according to claim 6, characterized in that: The selector valve (5) is a two-position six-way valve.

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