A tractor braking control system and a tractor having the same

Abstract

The present invention relates to a tractor braking control system and a tractor having the same. The tractor braking control system includes an oil pump, an automatic parking valve, a hand brake valve, a brake cylinder and a brake. The oil outlet end of the oil pump is connected and communicated with the oil inlet of the automatic parking valve and the oil inlet of the brake cylinder through pipelines respectively. The oil outlet of the automatic parking valve is connected with the oil inlet of the hand brake valve through a pipeline. The oil outlet of the hand brake valve is connected with the parking brake oil passage of the brake through a pipeline. The working oil port of the brake cylinder is connected with the service brake oil passage of the brake through a pipeline. The oil inlet end of the oil pump is connected with a fuel tank through a pipeline. The oil return ports of the automatic parking valve and the hand brake valve are connected with the fuel tank through pipelines respectively. Advantages: It can solve the problem that when the parking brake of the existing tractor is not released, the vehicle travels and burns the friction plate; it can achieve no rolling back during hill start; it can make the service brake and the parking brake associated, and the driving safety is higher.

Description

Technical Field

[0001] The present invention relates to the technical field of tractor braking, and particularly relates to a tractor braking control system and a tractor having the same. Background Art

[0002] At present, the tractor braking system is divided into a service braking system and a parking braking system. The control method of the parking braking system is to control the length of the wire by moving the control handle, so as to control the pressing of the brake pads. The control method of the service braking system is to step on the foot pedal to control the displacement of the master brake cylinder, so as to control the braking pressure to press the friction plates for braking. Generally, the service braking and the parking braking are not the same control mechanism, and there is no mutual association between the two.

[0003] Currently, the existing tractor braking system has the following defects:

[0004] 1) If the parking brake is not released after the vehicle starts, the vehicle can still move, which will seriously burn out the friction plates and lose the parking brake function after long-term operation.

[0005] 2) During the vehicle's hill start, the driver has to manually control the parking brake to increase the hill friction and then move forward, which is not intelligent and very inconvenient.

[0006] 3) The service braking and the parking braking are not associated and cannot perform intelligent combined braking. Summary of the Invention

[0007] The technical problem to be solved by the present invention is to provide a tractor braking control system and a tractor having the same, which effectively overcomes the defects of the prior art.

[0008] The technical solution of the present invention for solving the above technical problems is as follows:

[0009] A tractor braking control system includes an oil pump, an automatic parking valve, a hand brake valve, a brake cylinder and a brake. The oil outlet end of the oil pump is respectively connected and communicated with the oil inlet of the automatic parking valve and the oil inlet of the brake cylinder through pipelines. The oil outlet of the automatic parking valve is connected to the oil inlet of the hand brake valve through a pipeline. The oil outlet of the hand brake valve is connected to the parking brake oil passage of the brake through a pipeline. The working oil port of the brake cylinder is connected to the service brake oil passage of the brake through a pipeline. The oil inlet end of the oil pump is connected to a fuel tank through a pipeline. The oil return ports of the automatic parking valve and the hand brake valve are respectively connected to the fuel tank through pipelines. The brake cylinder is connected to a brake pedal.

[0010] Based on the above technical solution, the present invention can be further improved as follows.

[0011] Further, there are two of the above-mentioned brake cylinders, and there are two of the above-mentioned brakes, which are connected to the above-mentioned brake cylinders in one-to-one correspondence.

[0012] A brake accumulator is provided on the pipeline connecting the above-mentioned oil pump and the above-mentioned brake cylinder.

[0013] The above-mentioned automatic parking valve is a three-position four-way solenoid valve.

[0014] The above-mentioned hand brake valve is a two-position four-way valve.

[0015] A check valve is provided on the pipeline connected to the outlet end of the above-mentioned oil pump.

[0016] An overflow pipe connecting the above-mentioned oil tank is further provided at the oil outlet end of the above-mentioned oil pump, and a safety valve is provided on the above-mentioned overflow pipe.

[0017] A tractor is also provided, including a tractor braking control system.

[0018] Further, the above-mentioned automatic parking valve is a solenoid valve, the above-mentioned oil pump is drivingly connected to the engine of the tractor, the above-mentioned brake is provided with a pressure sensor, the main transmission shaft of the above-mentioned tractor is provided with a speed sensor, the above-mentioned hand brake valve is provided with a proximity switch for detecting its displacement, and the above-mentioned automatic parking valve, pressure sensor, and proximity switch are respectively connected to the controller of the above-mentioned tractor.

[0019] The beneficial effects of the present invention are as follows: The structure is reasonably designed, which can solve the problem that when the parking brake of the existing tractor is not released, the vehicle travels and burns the friction plate; it can achieve no vehicle rollback during a hill start; it can make the service brake and the parking brake associated, and the driving safety is higher. Description of the Drawings

[0020] Figure 1 It is a schematic structural diagram of the tractor braking control system of the present invention.

[0021] In the drawings, the list of components represented by each reference numeral is as follows:

[0022] 1. Oil pump; 2. Automatic parking valve; 3. Hand brake valve; 4. Brake cylinder; 5. Brake; 6. Fuel tank; 7. Brake accumulator; 8. Engine; 11. Check valve. Detailed Embodiments

[0023] The principles and features of the present invention will be described below with reference to the drawings. The examples given are only for explaining the present invention and are not intended to limit the scope of the present invention.

[0024] Example: As Figure 1As shown in the figure, the braking control system of the tractor in this embodiment includes an oil pump 1, an automatic parking valve 2, a hand brake valve 3, a brake cylinder 4, and a brake 5. The oil outlet end of the oil pump 1 is respectively connected and communicated with the oil inlet of the automatic parking valve 2 and the oil inlet of the brake cylinder 4 through pipelines. The oil outlet of the automatic parking valve 2 is connected to the oil inlet of the hand brake valve 3 through a pipeline. The oil outlet of the hand brake valve 3 is connected to the parking brake oil passage of the brake 5 through a pipeline. The working oil port of the brake cylinder 4 is connected to the service brake oil passage of the brake 5 through a pipeline. The oil inlet end of the oil pump 1 is connected to a fuel tank 6 through a pipeline. The oil return ports of the automatic parking valve 2 and the hand brake valve 3 are respectively connected to the fuel tank 6 through pipelines. The brake cylinder 4 is connected to a brake pedal.

[0025] In this embodiment, the automatic parking valve 2 can adopt a three-position four-way solenoid valve in the prior art.

[0026] It should be supplemented and explained that: the oil passage connecting the brake 5 and the brake cylinder 4 for service braking is the service brake oil passage, and the oil passage connecting the brake 5 and the hand brake valve 3 for releasing the brake is the parking brake oil passage. When oil enters the service brake oil passage, the push rod of the brake 5 will extend to hold the wheel hub tightly through the brake pads. When oil enters the parking brake oil passage, the disc will be compressed, causing the push rod to retract and releasing the state where the brake pads hold the wheel hub tightly.

[0027] During the actual use process, the braking control system of this tractor is connected to the central control system of the tractor's controller. Specifically, the automatic parking valve 2 is a solenoid valve, the brake 5 is provided with a pressure sensor, the main transmission shaft of the tractor is provided with a speed sensor, and the hand brake valve 3 is provided with a proximity switch for detecting its displacement. The automatic parking valve 2, the pressure sensor, and the proximity switch are respectively connected to the tractor's controller. The specific use process is as follows:

[0028] When the engine of the tractor is started, the oil pump 1 runs simultaneously and outputs pressurized oil. At this time, the control system of the tractor will detect the position of the handbrake handle of the hand brake valve 3 through the proximity switch to detect whether the handbrake handle is lowered or pulled up, and the stepping condition of the service brake pedal through the pressure sensor to detect whether there is pressure driving the brake cylinder 4 by the brake pedal. The specific usage method is as follows:

[0029] When the handbrake handle is lowered to the brake release position, the proximity switch detects this signal and feeds it back to the controller. The controller issues an instruction to open the oil inlet of the automatic parking valve 2 (such as Figure 1As shown, that is, the solenoid valve a of the automatic parking valve 2 is energized), the pressure oil will pass through the automatic parking valve 2-hand brake valve 3-brake 5, enter the parking brake oil channel of brake 5, and overcome the disc spring, thereby releasing the parking brake, and the vehicle can be driven. If the hand brake handle is in the parking brake position, the oil inlet of the automatic parking valve 2 is closed (such as Figure 1 As shown, that is, the solenoid valve b of the automatic parking valve 2 is energized), the disc spring will press the disc spring of the brake 5 to press the brake pad against the wheel hub to achieve parking brake. At this time, the vehicle cannot be driven, thereby solving the problem of serious burning of the friction pad;

[0030] When the vehicle is parked on a slope, during the start phase of the slope, the handbrake handle is in the parking brake release position. At this time, the vehicle has a tendency to slide down the slope, and the speed sensor detects that the main drive shaft has a reverse rotation speed (that is, the vehicle is moving backward), which is detected by the speed sensor and fed back to the controller. The controller issues a command, and the solenoid valve b of the automatic parking valve 2 is energized. In this way, even if the handbrake handle is in the brake release position, the vehicle still has the parking brake effect, so that it will not slide backward on the slope. At this time, when the vehicle is driving (stepping on the accelerator), the main drive shaft will have a forward rotation speed (that is, the vehicle is moving forward), which is detected by the speed sensor and fed back to the controller. The controller then issues a command, and the solenoid valve a of the automatic parking valve 2 is energized, completely releasing the parking brake state, thereby realizing the slope start function;

[0031] When the vehicle steps on the pedal while driving, the brake cylinder 4 will output pressure oil to control the brake 5 to hold the wheel hub, thereby realizing service braking. During this process, the pressure sensor will detect the service braking condition of the brake 5 and feed it back to the controller. The controller will then issue a command, and the solenoid valve b of the automatic parking valve 2 will be energized, thereby realizing dual braking of parking and driving, and realizing the association between service braking and parking braking.

[0032] The structural design of the whole system is reasonable, and it can effectively improve the problem of burning friction plates caused by vehicle running when the parking brake is not released in the existing tractor's braking control system; at the same time, it can achieve starting on a slope without slipping; in addition, it can realize the linkage between driving brake and parking brake.

[0033] It should be noted that: in this embodiment, the hand brake valve 3, the brake cylinder 4 and the brake 5 are conventional accessories in the prior art tractor, and their specific structures are not described here. At the same time, the proximity switch, the pressure sensor and the speed sensor are also conventional accessories in the tractor.

[0034] In this embodiment, the oil pump 1 is transmission-connected to the engine 8 of the tractor and obtains power from the engine 8 .

[0035] As a preferred embodiment, there are two of the above-mentioned brake cylinders 4, and there are two of the above-mentioned brakes 5, which are connected to the above-mentioned brake cylinders 4 in one-to-one correspondence.

[0036] In the above-mentioned implementation, the tractor is configured with two braking structures, one on each of the left and right sides, which is convenient for control.

[0037] In this embodiment, a brake accumulator 7 is provided on the pipeline connecting the above-mentioned oil pump 1 and the above-mentioned brake cylinder 4.

[0038] In this embodiment, the above-mentioned automatic parking valve 2 adopts a three-position four-way solenoid valve of the prior art, and its specific model can be flexibly and reasonably selected according to actual use requirements, and will not be elaborated here.

[0039] In this embodiment, the above-mentioned hand brake valve 3 adopts a conventional two-position four-way valve, and its specific model can be flexibly and reasonably selected according to actual use requirements, and will not be elaborated here.

[0040] In this embodiment, a check valve 11 is provided on the pipeline connected to the outlet end of the above-mentioned oil pump 1.

[0041] The following is a supplementary description of each core component involved in this embodiment:

[0042] The brake 5 is an actuator and is an element to achieve the braking of the tractor. The brake 5 presses against the tractor by the disc spring, and releasing the pressure of the disc spring can release the braking effect of the tractor.

[0043] The brake cylinder 4 is a control element and is a control element to achieve the driving braking of the tractor. When stepping on the brake cylinder 4, a pressure oil can be output to control the corresponding brake 5, and then the push rod of the brake 5 is pressed to extend, so as to achieve the driving braking of the tractor.

[0044] The brake accumulator 7 is a hydraulic accessory and is to achieve the reserve of the brake oil energy. When the system loses power, the brake accumulator 7 can also release the pressure oil to release the pressure of the disc spring, so as to achieve the function of releasing the parking brake and can perform operations such as towing.

[0045] The hand brake valve 3 is a control element and is a control element to achieve the parking brake. When manually pulling the hand brake valve 3, the pressure oil will be disconnected, and then the disc spring of the brake 5 will press against the push rod of the brake 5 to extend, so as to achieve the function of the parking brake.

[0046] The automatic parking valve 2 is a control component and is a control component for realizing automatic parking and hill-start assist. When the solenoid valve a of the automatic parking valve 2 is energized, the pressure oil source will pass through the automatic parking valve 2 and the hand brake valve 3 and enter the brake 5 to relieve the disc spring pressure, thereby realizing the function of releasing the parking brake. When the solenoid valve b of the automatic parking valve 2 is energized, the pressure oil source will be disconnected, so that the disc spring compresses and the push rod of the brake 5 extends, realizing the parking function. Even if there is no action of the hand brake valve 3 at this moment, the parking brake will also be carried out to realize automatic parking control.

[0047] The one-way valve 11 is a control component and is a control component for realizing the one-way transfer of the pressure oil source from the pump to the brake 5 direction.

[0048] The oil pump 1 is a power component and provides the power oil source for the braking system.

[0049] The safety valve (designated by d in the figure) is a control component and is a control component for controlling the safety pressure of the braking pressure oil source and belongs to the conventional accessories of the hydraulic and oil circuit systems. It can adjust the pressure for releasing the parking brake and the magnitude of the service brake assist pressure and belongs to the conventional accessories of the hydraulic and oil circuit systems.

[0050] In the description of the present invention, it should be understood that the orientation or positional relationship indicated by the terms "center", "longitudinal", "transverse", "length", "width", "thickness", "upper", "lower", "front", "rear", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer", "clockwise", "counterclockwise", "axial", "radial", "circumferential", etc. is based on the orientation or positional relationship shown in the drawings, and is only for the convenience of describing the present invention and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and thus cannot be construed as a limitation of the present invention.

[0051] In addition, the terms "first" and "second" are only used for descriptive purposes and cannot be construed as indicating or implying relative importance or implicitly specifying the quantity of the indicated technical features. Thus, the features defined with "first" and "second" may explicitly or implicitly include at least one of such features. In the description of the present invention, the meaning of "a plurality" is at least two, such as two, three, etc., unless otherwise specifically and clearly defined.

[0052] In the present invention, unless otherwise clearly defined or limited, terms such as "install", "connect", "join", "fix", etc. shall be understood in a broad sense. For example, it may be a fixed connection, a detachable connection, or integrated; it may be a mechanical connection or an electrical connection; it may be directly connected or indirectly connected through an intermediate medium, and it may be the internal communication of two components or the interaction relationship between two components, unless otherwise clearly defined. For those of ordinary skill in the art, the specific meanings of the above terms in the present invention can be understood according to specific circumstances.

[0053] In the present invention, unless otherwise clearly defined or limited, the first feature being "on" or "under" the second feature may be that the first and second features are in direct contact, or the first and second features are indirectly in contact through an intermediate medium. Moreover, the first feature being "above", "over" and "on top of" the second feature may be that the first feature is directly above or obliquely above the second feature, or merely indicates that the first feature has a higher horizontal height than the second feature. The first feature being "under", "below" and "beneath" the second feature may be that the first feature is directly below or obliquely below the second feature, or merely indicates that the first feature has a lower horizontal height than the second feature.

[0054] In the description of this specification, the description with reference to terms such as "one embodiment", "some embodiments", "example", "specific example", or "some examples", etc. means that the specific features, structures, materials, or characteristics described in connection with the embodiment or example are included in at least one embodiment or example of the present invention. In this specification, the schematic descriptions of the above terms do not necessarily refer to the same embodiment or example. Moreover, the specific features, structures, materials, or characteristics described can be combined in a suitable manner in any one or more embodiments or examples. In addition, without contradiction, those skilled in the art can combine and combine the different embodiments or examples described in this specification and the features of different embodiments or examples.

[0055] Although the embodiments of the present invention have been shown and described above, it can be understood that the above embodiments are exemplary and should not be construed as limiting the present invention. Those of ordinary skill in the art can make changes, modifications, substitutions, and variations to the above embodiments within the scope of the present invention.

Claims

1. A tractor braking control system, characterized in that: It includes an oil pump (1), an automatic parking valve (2), a hand brake valve (3), a brake cylinder (4) and a brake (5). The oil outlet end of the oil pump (1) is respectively connected and communicated with the oil inlet of the automatic parking valve (2) and the oil inlet of the brake cylinder (4) through pipelines. The oil outlet of the automatic parking valve (2) is connected to the oil inlet of the hand brake valve (3) through a pipeline. The oil outlet of the hand brake valve (3) is connected to the parking brake oil passage of the brake (5) through a pipeline. The working oil port of the brake cylinder (4) is connected to the service brake oil passage of the brake (5) through a pipeline. The oil inlet end of the oil pump (1) is connected to a fuel tank (6) through a pipeline. The oil return ports of the automatic parking valve (2) and the hand brake valve (3) are respectively connected to the fuel tank (6) through pipelines. The brake cylinder (4) is connected to a brake pedal. The automatic parking valve (2) is a three-position four-way solenoid valve. The hand brake valve (3) is a two-position four-way valve. The brake (5) brakes the tractor by being pressed out by a disc spring, and the braking effect of the tractor is released by releasing the pressure of the disc spring.

2. The braking control system of a tractor according to claim 1, characterized in that: There are two of the brake cylinders (4), and there are two of the brakes (5), which are connected in one-to-one correspondence with the brake cylinders (4).

3. A tractor braking control system according to claim 1, characterized in that: A brake accumulator (7) is provided on the pipeline connecting the oil pump (1) and the brake cylinder (4).

4. The braking control system of a tractor according to claim 1, characterized in that: A check valve (11) is provided on the pipeline connected to the outlet end of the oil pump (1).

5. A tractor braking control system according to claim 1, characterized in that: An overflow pipe connecting the fuel tank (6) is further provided at the oil outlet end of the oil pump (1), and a safety valve is provided on the overflow pipe.

6. A tractor, characterized in that: It includes a tractor braking control system according to any one of claims 1 to 5.

7. A tractor according to claim 6, characterized in that: The automatic parking valve (2) is a solenoid valve. The oil pump (1) is drivingly connected to the engine (8) of the tractor. The brake (5) is provided with a pressure sensor. A speed sensor is provided on the main transmission shaft of the tractor. The hand brake valve (3) is provided with a proximity switch for detecting its displacement. The automatic parking valve (2), the pressure sensor and the proximity switch are respectively connected to the controller of the tractor.

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