Front axle steering control system of tractor

Abstract

The utility model relates to the technical field of agricultural machinery, in particular to a front axle steering control system of a tractor. The system comprises a steering wheel, a left steering hydraulic cylinder installed on a front axle and a right steering hydraulic cylinder installed on the front axle, and further comprises a controller, and the controller is in communication connection with a steering wheel motor, a steering wheel sensor used for detecting the steering angle of the steering wheel, a front axle steering angle sensor used for detecting the steering angle of the vehicle and an electric full-hydraulic steering gear. And the electric full-hydraulic steering gear is connected with the left steering hydraulic cylinder, the right steering hydraulic cylinder and the oil supply device. The device has the advantages of continuous adjustment capability, high adjustment sensitivity and high precision.

Description

A tractor front axle steering control system Technical Field

[0001] This utility model relates to the field of agricultural machinery technology, specifically to a tractor front axle steering control system. Background Technology

[0002] The existing tractor front axle steering automatic control system adds a hydraulic valve to the original system. When automatic control is required, the hydraulic valve is switched in both directions to charge and discharge the steering hydraulic cylinder.

[0003] The above technical solution has the following disadvantages: it is abrupt during slow single adjustment and lacks the ability to adjust smoothly. At the same time, it is limited by the adjustable length of the hydraulic valve stem and the valve stem control accuracy. The multi-way valve flow output only has three to five obvious speed adjustment levels. This function will seriously affect the adjustment accuracy of navigation. Summary of the Invention

[0004] The purpose of this invention is to provide a tractor front axle steering control system that addresses the above problems, featuring continuous adjustment capability, high adjustment sensitivity, and high precision.

[0005] To achieve the above objectives, this utility model discloses a tractor front axle steering control system. The system includes a steering wheel, a left steering hydraulic cylinder mounted on the front axle, and a right steering hydraulic cylinder mounted on the front axle. It also includes a controller, which is communicatively connected to a steering wheel motor, a steering wheel sensor for detecting the steering wheel angle, a front axle angle sensor for detecting the wheel angle, and an electric full hydraulic steering gear. The electric full hydraulic steering gear is connected to the left steering hydraulic cylinder, the right steering hydraulic cylinder, and an oil supply device.

[0006] During operation, the controller acquires the rotation angle of the steering wheel motor. The electric hydraulic steering system has a metering output function, calculating the oil supply of the electric hydraulic steering system based on the steering wheel motor's rotation angle, and then calculating the steering angle of the front wheels. When the steering wheel motor is stopped, it is in a neutral state; when the steering wheel motor is turning, it can quantitatively acquire hydraulic oil, resulting in smooth hydraulic system operation. The steering wheel motor speed can be proportional to the wheel steering speed, with a wide speed adjustment range and continuous adjustment capability, high sensitivity, and high precision. How the controller acquires the steering wheel motor's rotation angle and calculates the front wheel steering angle utilizes existing technology and will not be elaborated upon here.

[0007] Preferably, the working port A of the electric full hydraulic steering gear is connected to the front end of the left steering hydraulic cylinder and the rear end of the right steering hydraulic cylinder; the working ports B and C of the electric full hydraulic steering gear are connected to the hydraulic motor; the shaft of the hydraulic motor is connected to the valve core of the electric full hydraulic steering gear; and the working port D of the electric full hydraulic steering gear is connected to the front end of the right steering hydraulic cylinder and the rear end of the left steering hydraulic cylinder.

[0008] When the wheel needs to turn left, the push rod of the left steering hydraulic cylinder extends and the push rod of the right steering hydraulic cylinder retracts, causing the wheel to turn to the left; when the wheel needs to turn right, the push rod of the left steering hydraulic cylinder retracts and the push rod of the right steering hydraulic cylinder extends, causing the wheel to turn to the right. The hydraulic motor is used to assist the movement of the valve core.

[0009] Preferably, when the oil inlet P of the electric full hydraulic steering gear is connected to the oil return port T of the electric full hydraulic steering gear, the working ports A, B, C and D are all closed.

[0010] At this time, the steering wheel motor does not turn, and the push rods of the left and right steering hydraulic cylinders do not move, so the wheels maintain the steering angle.

[0011] When the oil inlet P is connected to the working oil inlet B, the working oil inlet C is connected to the working oil inlet D, and the working oil inlet A is connected to the return oil inlet T.

[0012] At this time, the steering wheel motor rotates, and the hydraulic oil enters the hydraulic motor through the working oil port B, and then enters the rear end of the left steering hydraulic cylinder and the front end of the right steering hydraulic cylinder through the working oil ports C and D. The push rod of the left steering hydraulic cylinder extends, and the push rod of the right steering hydraulic cylinder retracts, causing the wheel to turn to the left.

[0013] When the oil inlet P is connected to the working oil inlet C, the working oil inlet B is connected to the working oil inlet A, and the working oil inlet D is connected to the return oil inlet T.

[0014] At this time, the steering wheel motor rotates, and the hydraulic oil enters the hydraulic motor through the working port C, and then enters the front end of the left steering hydraulic cylinder and the rear end of the right steering hydraulic cylinder through the working port B and the working port. The push rod of the left steering hydraulic cylinder retracts, and the push rod of the right steering hydraulic cylinder extends, causing the wheel to turn to the right.

[0015] Preferably, the oil supply device includes an oil tank, the oil tank is connected to an oil pump, and the oil pump is connected to the oil inlet P of the electric full hydraulic steering gear.

[0016] During use, the oil pump delivers hydraulic oil from the tank to the electric fully hydraulic steering system.

[0017] Preferably, the oil tank is connected to a filter, and the filter is connected to the return port T of the electric full hydraulic steering gear.

[0018] When in use, the filter is used to filter impurities in the return oil at the return port T, keeping the hydraulic oil clean.

[0019] Preferably, a check valve is connected between the oil inlet P and the oil return port T, and the check valve prevents hydraulic oil from flowing from the oil inlet P side to the oil return port T side.

[0020] During use, the check valve prevents hydraulic oil from flowing from the inlet P side to the return T side, ensuring safe operation.

[0021] Preferably, an overflow valve is connected between the oil inlet P and the oil return port T.

[0022] When in use, if the hydraulic oil pressure at the inlet P is high, the hydraulic oil will flow back to the oil tank through the relief valve to ensure safe use.

[0023] In summary, the beneficial effects of this utility model are as follows: During use, the controller acquires the rotation angle of the steering wheel motor; the electric full hydraulic steering system has a metering output function, calculating the oil supply of the electric full hydraulic steering system based on the steering wheel motor's rotation angle, and thus calculating the steering angle of the front wheels; it is in a neutral state when the steering wheel motor is stopped, and can quantitatively acquire hydraulic oil when the steering wheel motor is turning, resulting in smooth hydraulic system operation; the steering wheel motor speed can be proportional to the wheel steering speed, the steering wheel motor speed adjustment range is wide, and it has continuous adjustment capability. Attached Figure Description

[0024] Figure 1 is a schematic diagram of the structure of a tractor front axle steering control system according to the present invention.

[0025] Figure 2 is a schematic diagram of the hydraulic system in the front axle steering control system of a tractor according to this utility model.

[0026] In the diagram: 1. Steering wheel; 2. Steering wheel motor; 3. Steering wheel sensor; 4. Controller; 5. Front axle angle sensor; 6. Oil tank; 7. Oil pump; 8. Filter; 9. Electric full hydraulic steering gear; 10. Front axle; 11. Left steering hydraulic cylinder; 12. Right steering hydraulic cylinder; 13. Relief valve; 14. Check valve; 15. Hydraulic motor. Detailed Implementation

[0027] The specific embodiments of this utility model will be further described in detail below with reference to the accompanying drawings and examples. The following examples are used to illustrate this utility model, but are not intended to limit the scope of this utility model.

[0028] In the description of this application, it should be noted that, unless otherwise expressly specified and limited, the terms "installation," "connection," and "linking" should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral connection; they can refer to a mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium; and they can refer to the internal connection between two components. Those skilled in the art can understand the specific meaning of the above terms in this application based on the specific circumstances.

[0029] As shown in Figure 1, a tractor front axle steering control system includes a steering wheel 1, a left steering hydraulic cylinder 11 mounted on the front axle 10, and a right steering hydraulic cylinder 12 mounted on the front axle 10. It also includes a controller 4, which is communicatively connected to a steering wheel motor 2, a steering wheel sensor 3 for detecting the steering angle of the steering wheel 1, a front axle steering angle sensor 5 for detecting the wheel steering angle, and an electric full hydraulic steering gear 9. The electric full hydraulic steering gear 9 is connected to the left steering hydraulic cylinder 11, the right steering hydraulic cylinder 12, and an oil supply device. In use, the controller 4 acquires the rotation angle of the steering wheel motor 2. The electric full hydraulic steering gear 9 has a metering output function, which calculates the oil supply of the electric full hydraulic steering gear 9 based on the rotation angle of the steering wheel motor 2, and then calculates the steering angle of the front wheels. When the steering wheel motor 2 is stopped, it is in a neutral state. When the steering wheel motor 2 is turning, it can acquire hydraulic oil in a metered manner, making the hydraulic system work smoothly. The speed of the steering wheel motor 2 can be proportional to the steering speed of the wheels. The speed of the steering wheel motor 2 has a wide adjustment range and continuous adjustment capability, with high adjustment sensitivity and high precision. How the controller 4 acquires the rotation angle of the steering wheel motor 2 and how it calculates the steering angle of the front wheels are all based on existing technology, and will not be described in detail here.

[0030] As shown in Figure 2, the working port A of the electric full hydraulic steering gear 9 is connected to the front end of the left steering hydraulic cylinder 11 and the rear end of the right steering hydraulic cylinder 12. Working ports B and C of the electric full hydraulic steering gear 9 are connected to the hydraulic motor 15. The shaft of the hydraulic motor 15 is connected to the valve core of the electric full hydraulic steering gear 9. The working port D of the electric full hydraulic steering gear 9 is connected to the front end of the right steering hydraulic cylinder 12 and the rear end of the left steering hydraulic cylinder 11. When the wheel needs to turn left, the push rod of the left steering hydraulic cylinder 11 extends, and the push rod of the right steering hydraulic cylinder 12 retracts, causing the wheel to turn to the left. When the wheel needs to turn right, the push rod of the left steering hydraulic cylinder 11 retracts, and the push rod of the right steering hydraulic cylinder 12 extends, causing the wheel to turn to the right. The hydraulic motor 15 assists in the movement of the valve core.

[0031] Specifically, when the inlet P of the electric hydraulic steering gear 9 is connected to the return port T, the working ports A, B, C, and D are all closed. At this time, the steering wheel motor 2 does not rotate, and the push rods of the left steering cylinder 11 and the right steering cylinder 12 do not move, maintaining the steering angle of the wheels. When the inlet P is connected to the working port B, the working ports C and D are connected, and the working port A is connected to the return port T. At this time, the steering wheel motor 2 rotates, and hydraulic oil enters the hydraulic motor 15 through the working port B, then enters the rear end of the left steering cylinder 11 and the front end of the right steering cylinder 12 through the working ports C and D. The push rod of the left steering cylinder 11 extends, and the push rod of the right steering cylinder 12 retracts, causing the wheels to turn to the left. When the inlet P is connected to the working port C, the working ports B and A are connected, and the working port D is connected to the return port T. At this time, the steering wheel motor 2 rotates, and the hydraulic oil enters the hydraulic motor 15 through the working oil port C, and then enters the front end of the left steering hydraulic cylinder 11 and the rear end of the right steering hydraulic cylinder 12 through the working oil port B and the working oil port 1. The push rod of the left steering hydraulic cylinder 11 retracts, and the push rod of the right steering hydraulic cylinder 12 extends, causing the wheel to turn to the right.

[0032] Specifically, the oil supply device includes an oil tank 6, which is connected to an oil pump 7. The oil pump 7 is connected to the oil inlet P of the electric hydraulic steering gear 9. During operation, the oil pump 7 supplies hydraulic oil from the oil tank 6 to the electric hydraulic steering gear 9. An oil filter 8 is connected to the oil tank 6, and the filter 8 is connected to the return port T of the electric hydraulic steering gear 9. During operation, the filter 8 filters impurities in the return oil at the return port T, keeping the hydraulic oil clean. A one-way valve 14 is connected between the oil inlet P and the return port T. The one-way valve 14 prevents hydraulic oil from flowing from the oil inlet P side to the return port T side, ensuring safe operation. An overflow valve 13 is connected between the oil inlet P and the return port T. During operation, when the hydraulic oil pressure at the oil inlet P is high, the hydraulic oil flows back to the oil tank 6 through the overflow valve 13, ensuring safe operation.

[0033] The above description is only a preferred embodiment of the present utility model. It should be noted that for those skilled in the art, several improvements and substitutions can be made without departing from the technical principles of the present utility model, and these improvements and substitutions should also be considered within the protection scope of the present utility model.

Claims

1. A tractor front axle steering control system, comprising a steering wheel (1), a left steering hydraulic cylinder (11) mounted on the front axle (10), and a right steering hydraulic cylinder (12) mounted on the front axle (10), characterized in that, It also includes a controller (4), which is connected to a steering wheel motor (2), a steering wheel sensor (3) for detecting the steering wheel (1) angle, a front axle angle sensor (5) for detecting the wheel angle, and an electric full hydraulic steering gear (9). The electric full hydraulic steering gear (9) is connected to the left steering hydraulic cylinder (11), the right steering hydraulic cylinder (12), and the oil supply device.

2. The tractor front axle steering control system as described in claim 1, characterized in that, The working port A of the electric full hydraulic steering gear (9) is connected to the front end of the left steering hydraulic cylinder (11) and the rear end of the right steering hydraulic cylinder (12). The working ports B and C of the electric full hydraulic steering gear (9) are connected to the hydraulic motor (15). The rotating shaft of the hydraulic motor (15) is connected to the valve core of the electric full hydraulic steering gear (9). The working port D of the electric full hydraulic steering gear (9) is connected to the front end of the right steering hydraulic cylinder (12) and the rear end of the left steering hydraulic cylinder (11).

3. The tractor front axle steering control system as described in claim 2, characterized in that, When the oil inlet P of the electric full hydraulic steering gear (9) is connected to the oil return port T of the electric full hydraulic steering gear (9), the working ports A, B, C and D are all closed; when the oil inlet P is connected to the working port B, the working port C is connected to the working port D, and the working port A is connected to the oil return port T; when the oil inlet P is connected to the working port C, the working port B is connected to the working port A, and the working port D is connected to the oil return port T.

4. The tractor front axle steering control system as described in claim 2, characterized in that, The oil supply device includes an oil tank (6), an oil pump (7) connected to the oil tank (6), and the oil pump (7) is connected to the oil inlet P of the electric full hydraulic steering gear (9).

5. The tractor front axle steering control system as described in claim 4, characterized in that, The oil tank (6) is connected to a filter (8), which is connected to the return port T of the electric full hydraulic steering gear (9).

6. The tractor front axle steering control system as described in claim 5, characterized in that, A check valve (14) is connected between the oil inlet P and the oil return port T. The check valve (14) prevents hydraulic oil from flowing from the oil inlet P side to the oil return port T side.

7. The tractor front axle steering control system as described in claim 5, characterized in that, An overflow valve (13) is connected between the oil inlet P and the oil return port T.

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