A four-wheel hydraulic brake system for tractors in hilly and mountainous areas

Abstract

A four-wheel hydraulic brake system for a tractor operating in hilly and mountainous areas comprises a left front brake and a right front brake respectively mounted on either side of a gearbox, a left rear brake and a right rear brake respectively mounted on either side of a rear axle, and a brake oil tank and a brake pump for supplying oil to the brakes. Brake pistons capable of pushing a friction plate assembly to move are provided in the brake housings of the four brakes. A left brake pedal assembly and a right brake pedal assembly are provided in the cab of the tractor. Movement of the left and right brake pedals can drive the flow of hydraulic oil through the brake pump, and the flow direction of the hydraulic oil is adjusted by the cooperation of a diverter valve and a reverse hydraulic lock. When the left and right brake pedals move simultaneously, the reverse hydraulic lock opens in both directions, allowing hydraulic oil to flow into the four brakes simultaneously, thereby achieving four-wheel braking of the tractor. When a single left or right brake pedal moves, the reverse hydraulic lock remains closed, allowing hydraulic oil to flow into only one brake located at the rear, thereby achieving single-sided rear wheel braking of the tractor.

Description

Technical Field

[0001] The present invention relates to the field of hilly and mountainous area tractors, and in particular to a four-wheel hydraulic brake system for hilly and mountainous area tractors. Background Art

[0002] my country's vast hilly and mountainous regions are dominated by irregular terrain and sloping terrain. These terrains are characterized by winding and narrow roads, small plots of land, and a complex array of crop varieties and cultivation techniques, resulting in harsh operating conditions. Traditional agricultural tractors only have mechanical or hydraulic rear wheel brakes, which commonly suffer from weak slope adaptability and poor braking performance when operating in hilly and mountainous terrain. Consequently, the market urgently demands highly reliable machinery for hilly and mountainous operations, characterized by strong slope adaptability, excellent braking performance, and the ability to brake on all four wheels for bidirectional operation. Summary of the Invention

[0003] In order to solve the problems of weak slope adaptability and poor braking performance of existing tractors, the present invention provides a four-wheel hydraulic braking system for hilly and mountainous tractors.

[0004] The technical solution adopted by the present invention to solve the above-mentioned technical problems is: a four-wheel hydraulic brake system for a hilly mountain tractor, comprising a left front brake and a right front brake respectively mounted on both sides of a transmission, a left rear brake and a right rear brake respectively mounted on both sides of a rear axle, and a brake oil tank and a brake pump for supplying oil to the left front brake, the left rear brake, the right front brake, and the right rear brake. The left front brake and the left rear brake each include a left brake housing, and the right front brake and the right rear brake each include a right brake housing. The inner cavities of the left brake housing and the right brake housing are each provided with a brake piston capable of driving a friction plate assembly.

[0005] The brake oil tank is connected to the left oil inlet and right oil inlet of the brake pump through two brake pump oil inlet pipes, respectively. The left oil outlet and right oil outlet of the brake pump are respectively connected to oil outlet hoses, and the two oil outlet hoses are respectively connected to the A port and B port of the diverter valve. The tractor cab is provided with a left brake pedal assembly and a right brake pedal assembly. The left brake pedal assembly and the right brake pedal assembly are respectively connected to the two push rods of the brake pump through their respective brake connecting rods. When the left brake pedal assembly rotates, the hydraulic oil can flow from the brake pump into the B port of the diverter valve through the movement of the corresponding push rod. When the right brake pedal assembly rotates, the hydraulic oil can flow from the brake pump into the A port of the diverter valve through the movement of the corresponding push rod.

[0006] The diverter valve is provided with ports I and II interconnected with port A, and ports III and IV interconnected with port B. Port I is connected to the rear right brake oil pipe, which is connected to the right rear brake, so that the hydraulic oil from port A can flow into the right brake housing of the right rear brake, so that the brake piston of the right rear brake pushes the friction plate assembly to press against the right side wall of the rear axle for braking. Port III is connected to the rear left brake oil pipe, which is connected to the left rear brake, so that the hydraulic oil from port B can flow into the left brake housing of the left rear brake, so that the brake piston of the left rear brake pushes the friction plate assembly to press against the left side wall of the rear axle for braking.

[0007] Port Ⅱ and port Ⅳ are connected to their own front brake hoses respectively. The front brake hose of port Ⅱ is connected to port V1 of the reverse hydraulic lock, and the front brake hose of port Ⅳ is connected to port V2 of the reverse hydraulic lock. Port C1 of the reverse hydraulic lock is connected to the right front brake, and port C2 of the reverse hydraulic lock is connected to the left front brake. When hydraulic oil flows into one of port V1 and port V2, port C1 and port C2 remain closed. When hydraulic oil flows into port V1 and port V2 at the same time, port C1 and port C2 can be opened, so that the hydraulic oil in port A can flow into the right brake housing of the right front brake, and the hydraulic oil in port B can flow into the left brake housing of the left front brake, so that the brake pistons of the left front brake and the right front brake respectively push their respective friction plate assemblies to squeeze the left and right side walls of the gearbox for braking.

[0008] Preferably, a piston sealing ring is provided on the brake piston.

[0009] Preferably, the diverter valve and the reverse hydraulic lock are respectively mounted on a bottom plate bracket of the tractor.

[0010] Preferably, a pipe clamp is installed on the bottom plate of the tractor, and two oil outlet hoses are clamped by the pipe clamp.

[0011] Preferably, the top sides of the left brake housing and the right brake housing are provided with air bleed screws, and the bottom sides are provided with oil drain plugs.

[0012] Preferably, the left brake pedal assembly and the right brake pedal assembly are cooperated with each other and are provided with a limit pin, so that the left brake pedal assembly and the right brake pedal assembly can rotate synchronously.

[0013] According to the above technical solution, the beneficial effects of the present invention are:

[0014] In the present invention, the movement of the left and right brake pedals drives the flow of hydraulic oil, and the flow direction of the hydraulic oil is adjusted by the cooperation of a diverter valve and a reverse hydraulic lock. Therefore, when the left and right brake pedals are moved simultaneously, the reverse hydraulic lock opens in both directions, allowing hydraulic oil to flow simultaneously into all four brakes, achieving four-wheel braking of the tractor. However, when only one of the left and right brake pedals is moved, the reverse hydraulic lock remains closed, and hydraulic oil only flows into the rear brake corresponding to the left or right brake pedal, achieving single-side rear wheel braking of the tractor. Four-wheel braking can increase braking deceleration, reduce braking distance, and improve the reliability of the tractor, meeting the market's urgent demand for safety performance in hilly and mountainous tractors. Single-side rear wheel braking can reduce the tractor's turning radius, further enhancing the tractor's adaptability to hilly and mountainous terrain. The hydraulic braking system uses oil pressure to drive the friction plate for smoother braking. Both four-wheel braking and single-side rear wheel braking can be achieved simply by controlling the simultaneous or individual movement of the left and right brake pedals, eliminating the need for a more complex control process. Switching between the two braking modes can be achieved efficiently and reliably. The use of a hose in the hydraulic braking system accommodates the needs of bidirectional tractor operation. BRIEF DESCRIPTION OF THE DRAWINGS

[0015] Figure 1 It is a top view schematic diagram of the present invention;

[0016] Figure 2 The main schematic diagram for omitting the gearbox and rear axle;

[0017] Figure 3 This is the schematic diagram of the hydraulic system.

[0018] Markings in the figure: 1. gearbox, 2. rear axle, 3. left front brake, 4. left rear brake, 5. right front brake, 6. right rear brake, 7. left brake housing, 8. friction plate assembly, 9. brake piston, 10. piston seal, 11. right brake pedal assembly, 12. left brake pedal assembly, 13. brake oil tank, 14. brake pump inlet pipe, 15. brake pump, 16. oil outlet hose, 17. diverter valve, 18. front brake hose, 19. reverse hydraulic lock, 20. front right brake oil pipe, 21. front left brake oil pipe, 22. rear right brake oil pipe, 23. rear left brake oil pipe, 24. brake connecting rod, 25. bleed screw, 26. drain plug, 27. pipe clamp assembly, 28. right brake housing. DETAILED DESCRIPTION

[0019] With reference to the accompanying drawings, the specific implementation is as follows:

[0020] like Figure 1As shown, a four-wheel hydraulic brake system for a hilly mountain tractor includes a left front brake 3 and a right front brake 5 respectively mounted on both sides of a gearbox 1, a left rear brake 4 and a right rear brake 6 respectively mounted on both sides of a rear axle 2, and a brake oil tank 13 and a brake pump 15 for supplying oil to the left front brake 3, the left rear brake 4, the right front brake 5 and the right rear brake 6. The system is characterized in that: the left front brake 3 and the left rear brake 4 each include a left brake housing 7, the right front brake 5 and the right rear brake 6 each include a right brake housing 28, a brake piston 9 capable of pushing a friction plate assembly 8 to move is provided in the inner cavity of the left brake housing 7 and the right brake housing 28, a piston sealing ring 10 is provided on the brake piston 9, and a bleed screw 25 is provided on the top side of the left brake housing 7 and the right brake housing 28, and an oil drain plug 26 is provided on the bottom side.

[0021] like Figure 2 、 3 As shown, the brake oil tank 13 is connected to the left oil inlet and the right oil inlet of the brake pump 15 through two brake pump oil inlet pipes 14 respectively, and the left oil outlet and the right oil outlet of the brake pump 15 are respectively connected to the oil outlet hose 16, and the two oil outlet hoses 16 are respectively connected to the A port and the B port of the diverter valve 17. A left brake pedal assembly 12 and a right brake pedal assembly 11 are provided in the tractor's cab. The left brake pedal assembly 12 and the right brake pedal assembly 11 are respectively connected to the two push rods of the brake pump 15 through their own brake connecting rods 24. When the left brake pedal assembly 12 rotates, the hydraulic oil can flow from the brake pump 15 into the B port of the diverter valve 17 through the movement of the corresponding push rod. When the right brake pedal assembly 11 rotates, the hydraulic oil can flow from the brake pump 15 into the A port of the diverter valve 17 through the movement of the corresponding push rod.

[0022] like Figure 3 As shown, the diverter valve 17 is provided with port I and port II which are interconnected with port A, and port III and port IV which are interconnected with port B. Port I is connected to the rear right brake oil pipe 22, which is connected to the right rear brake 6, so that the hydraulic oil of port A can flow into the right brake housing 28 of the right rear brake 6, and the brake piston 9 of the right rear brake 6 is subjected to the action of oil pressure in the right brake housing 28, pushing the friction plate assembly 8 to squeeze the right side wall of the rear axle 2 for braking, and port III is connected to the rear left brake oil pipe 23, which is connected to the left rear brake 4, so that the hydraulic oil of port B can flow into the left brake housing 7 of the left rear brake 4, and the brake piston 9 of the left rear brake 4 is subjected to the action of oil pressure in the left brake housing 7, pushing the friction plate assembly 8 to squeeze the left side wall of the rear axle 2 for braking.

[0023] like Figure 3As shown, ports II and IV are each connected to a respective front brake hose 18. Port II's front brake hose 18 is connected to port V1 of a reverse hydraulic lock 19, while port IV's front brake hose 18 is connected to port V2 of the reverse hydraulic lock 19. Port C1 of the reverse hydraulic lock 19 is connected to the right front brake 5, while port C2 of the reverse hydraulic lock 19 is connected to the left front brake 3. Diverter valve 17 and reverse hydraulic lock 19 are each mounted on a tractor's floor bracket. A pipe clamp is mounted on the tractor's floor, securing two oil outlet hoses 16 via the clamp.

[0024] When the hydraulic oil flows into one of the V1 ports and the V2 ports, the C1 port and the C2 port both remain closed. When the hydraulic oil flows into the V1 port and the V2 port at the same time, the C1 port and the C2 port can be opened, so that the hydraulic oil in the A port can flow into the right brake housing 28 of the right front brake 5, and the hydraulic oil in the B port can flow into the left brake housing 7 of the left front brake 3. The brake piston 9 of the left front brake 3 is acted upon by the oil pressure in the left brake housing 7, and the brake piston 9 of the right front brake 5 is acted upon by the oil pressure in the right brake housing 28, respectively pushing their respective friction plate assemblies 8 to squeeze the left and right side walls of the gearbox 1 for braking.

[0025] When the hydraulic oil flows into the V1 port and the V2 port at the same time, it means that the hydraulic oil will inevitably flow out from the I port and the III port of the diverter valve 17 at the same time. At this time, the hydraulic oil will flow into the left front brake 3, the left rear brake 4, the right front brake 5 and the right rear brake 6 at the same time. Therefore, when the left brake pedal assembly 12 and the right brake pedal assembly 11 rotate synchronously, the four brakes will be braked at the same time, that is, the four-wheel braking of the tractor is realized.

[0026] When one of the left brake pedal assembly 12 and the right brake pedal assembly 11 rotates alone, since only one of the A and B ports of the diverter valve 17 will have oil inlet, the hydraulic oil will only flow into one of the V1 and V2 ports, and the C1 and C2 ports will not be able to open. The hydraulic oil will eventually flow out of only the one of the I and III ports corresponding to the rotating pedal assembly, and only the rear one of the four brakes will brake, thus achieving single-side rear wheel braking of the tractor.

[0027] To enable quick switching between four-wheel braking and single-rear-wheel braking, removable stop pins are installed on both the left and right brake pedal assemblies 12, 11. When the driver steps on either the left or right brake pedal assembly 12, 11, they rotate synchronously, achieving four-wheel braking. By removing the stop pins, the driver steps on either the left or right brake pedal assembly 12, 11, causing only one of the two to rotate, switching to single-rear-wheel braking.

Claims

1. A four-wheel hydraulic brake system for a hilly mountain tractor, comprising a left front brake (3) and a right front brake (5) respectively mounted on both sides of a gearbox (1), a left rear brake (4) and a right rear brake (6) respectively mounted on both sides of a rear axle (2), and a brake oil tank (13) and a brake pump (15) for supplying oil to the left front brake (3), the left rear brake (4), the right front brake (5) and the right rear brake (6), characterized in that: The left front brake (3) and the left rear brake (4) both include a left brake housing (7), and the right front brake (5) and the right rear brake (6) both include a right brake housing (28). A brake piston (9) capable of pushing the friction plate assembly (8) to move is provided in the inner cavity of the left brake housing (7) and the right brake housing (28); The brake oil tank (13) is connected to the left oil inlet and the right oil inlet of the brake pump (15) through two brake pump oil inlet pipes (14), respectively. The left oil outlet and the right oil outlet of the brake pump (15) are connected to oil outlet hoses (16), respectively. The two oil outlet hoses (16) are connected to the A port and the B port of the diverter valve (17), respectively. A left brake pedal assembly (12) and a right brake pedal assembly (11) are provided in the tractor cab. The left brake pedal assembly (12) and the right brake pedal assembly (11) are connected to the two push rods of the brake pump (15) through their respective brake connecting rods (24). When the left brake pedal assembly (12) rotates, the hydraulic oil can flow from the brake pump (15) into the B port of the diverter valve (17) through the movement of the corresponding push rod. When the right brake pedal assembly (11) rotates, the hydraulic oil can flow from the brake pump (15) into the A port of the diverter valve (17) through the movement of the corresponding push rod. The diverter valve (17) is provided with ports I and II that are interconnected with port A, and ports III and IV that are interconnected with port B. Port I is connected to a rear right brake oil pipe (22), which is connected to the right rear brake (6), so that the hydraulic oil of port A can flow into the right brake housing (28) of the right rear brake (6), so that the brake piston (9) of the right rear brake (6) pushes the friction plate assembly (8) to squeeze the right side wall of the rear axle (2) for braking. Port III is connected to a rear left brake oil pipe (23), which is connected to the left rear brake (4), so that the hydraulic oil of port B can flow into the left brake housing (7) of the left rear brake (4), so that the brake piston (9) of the left rear brake (4) pushes the friction plate assembly (8) to squeeze the left side wall of the rear axle (2) for braking. Port II and port IV are connected to respective front brake hoses (18), the front brake hose (18) of port II is connected to port V1 of the reverse hydraulic lock (19), the front brake hose (18) of port IV is connected to port V2 of the reverse hydraulic lock (19), the C1 port of the reverse hydraulic lock (19) is connected to the right front brake (5), and the C2 port of the reverse hydraulic lock (19) is connected to the left front brake (3). When the hydraulic oil flows into one of the V1 port and the V2 port, the C1 port and the C2 port are connected. The ports are kept closed. When hydraulic oil flows into the V1 port and the V2 port at the same time, the C1 port and the C2 port can be opened, so that the hydraulic oil of the A port can flow into the right brake housing (28) of the right front brake (5), and the hydraulic oil of the B port can flow into the left brake housing (7) of the left front brake (3), so that the brake pistons (9) of the left front brake (3) and the right front brake (5) respectively push their respective friction plate assemblies (8) to squeeze the left and right side walls of the transmission case (1) for braking.

2. A four-wheel hydraulic brake system for a hilly mountain tractor according to claim 1, characterized in that: A piston sealing ring (10) is provided on the brake piston (9).

3. The four-wheel hydraulic brake system for a hilly mountain tractor according to claim 1, characterized in that: The diverter valve (17) and the reverse hydraulic lock (19) are respectively mounted on the bottom plate bracket of the tractor.

4. A four-wheel hydraulic brake system for a hilly mountain tractor according to claim 3, characterized in that: A pipe clamp is installed on the bottom plate of the tractor, and two oil outlet hoses (16) are clamped by the pipe clamp.

5. The four-wheel hydraulic brake system for a hilly mountain tractor according to claim 1, characterized in that: The left brake housing (7) and the right brake housing (28) are both provided with an air bleed screw (25) on the top side and an oil drain plug (26) on the bottom side.

6. The four-wheel hydraulic brake system for a hilly mountain tractor according to claim 1, characterized in that: The left brake pedal assembly (12) and the right brake pedal assembly (11) are cooperatively provided with a limit pin, so that the left brake pedal assembly (12) and the right brake pedal assembly (11) can rotate synchronously.

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