Steering mechanism, method for controlling steering mechanism, and work machine

Abstract

The invention belongs to the technical field of hydraulic control, and particularly relates to a steering mechanism, a control method of the steering mechanism and an operation machine.The steering mechanism comprises an axle, a steering wheel and a hydraulic control system, and the hydraulic control system comprises a power-assisted steering oil cylinder used for driving the axle to execute steering operation; the oil supply path is used for supplying oil to the power-assisted steering oil cylinder; the electric control reversing valve is arranged on the oil supply way, and two working oil ports of the electric control reversing valve are communicated with a rod cavity and a rodless cavity of the power-assisted steering oil cylinder respectively; the control unit is in communication connection with the electric control reversing valve and is configured to determine the turning angle of an axle under the condition that it is determined that the driver does not place the two hands on a steering wheel; and the working position of the electric control reversing valve is switched according to the turning angle, so that the power-assisted steering oil cylinder drives the axle to return, and the steering wheel is driven to return. By the adoption of the steering mechanism, when the two hands of a driver leave the steering wheel, the power-assisted steering oil cylinder can be automatically controlled to drive the axle and the steering wheel to return.

Description

Technical Field

[0001] The present application belongs to the field of hydraulic control technology, and specifically relates to a steering mechanism, a control method of the steering mechanism, and an operating machine. Background Art

[0002] The vehicle's wheels are mostly controlled by the steering wheel, which in turn controls the direction of the steering cylinder. The steering wheel is connected to the main control valve of the vehicle's travel mechanism, and the direction of the steering cylinder's movement is adjusted by controlling the working position of the main control valve.

[0003] When designing a vehicle that requires an automatic self-centering function, conventional vehicles often incorporate a steering assist spring into the steering wheel structure to assist in returning the steering wheel to the center position. This allows the steering wheel to control the steering assist cylinder, which in turn drives the travel wheels to the center position. However, this self-centering method, while designed to enhance the driver's driving experience, typically requires a relatively weak spring force, making it difficult to return the steering wheel and travel wheels to the center position. Summary of the Invention

[0004] The purpose of this application is to provide a steering mechanism, a control method for the steering mechanism and an operating machine to solve the technical problem in the prior art that the driver's hands leave the steering wheel and the steering wheel cannot automatically return to the neutral position.

[0005] In order to achieve the above objectives, the present application provides a steering mechanism, which includes an axle, a steering wheel, and a hydraulic control system. The hydraulic control system includes: Power steering cylinder, used to drive the axle to perform steering operations; Oil supply line, used to supply oil to the power steering cylinder; The electronically controlled reversing valve is provided on the oil supply line, and the two working oil ports of the electronically controlled reversing valve are respectively connected to the rod chamber and the rodless chamber of the power steering cylinder; The control unit is in communication with the electronically controlled reversing valve and is configured to: determine the turning angle of the vehicle axle when it is determined that the driver does not place both hands on the steering wheel; switch the working position of the electronically controlled reversing valve according to the turning angle so that the steering power cylinder drives the vehicle axle to return to the center position, thereby driving the steering wheel to return to the center position.

[0006] In some embodiments, the electronically controlled reversing valve includes an intermediate cutoff position, a forward guide position, and a reverse guide position, and the control unit is further configured to: when it is determined that the driver has not placed both hands on the steering wheel and the axle has a turning angle, control the electronically controlled reversing valve to switch to the forward guide position or the reverse guide position to drive the piston rod of the power steering cylinder to extend and retract; when it is determined that the driver has not placed both hands on the steering wheel and the axle is in the return direction, control the electronically controlled reversing valve to switch to the intermediate cutoff position to cut off the oil supply circuit and the power steering cylinder.

[0007] In some embodiments, the hydraulic control system also includes: a main control valve, which is arranged on the oil supply circuit and connected to the steering wheel, the main control valve having two working oil ports and two control oil ports, the two working oil ports of the main control valve are respectively connected to the rod chamber and rodless chamber of the steering power cylinder, and the two control oil ports of the main control valve are respectively connected to the oil inlet and oil outlet of the electronically controlled reversing valve. When the steering wheel is stationary or the driver does not place his hands on the steering wheel, the main control valve connects the oil supply circuit to the electronically controlled reversing valve.

[0008] In some embodiments, the main control valve includes a first turning position, a second turning position, and a turning stop position. When the main control valve is in the turning stop position, the oil supply circuit controlled by the main control valve is connected to the electronically controlled reversing valve; when the main control valve is in the first turning position or the second turning position, the oil supply circuit controlled by the main control valve is connected to the steering power cylinder.

[0009] In some embodiments, the steering mechanism further includes a steering wheel detection unit communicatively connected to the control unit, the steering wheel detection unit being configured to detect in real time whether the driver places both hands on the steering wheel and send a control signal to the control unit.

[0010] In some embodiments, the steering mechanism further includes an angle detection unit mounted on the axle, and the angle detection unit is configured to detect a turning angle of the axle and send the detected angle to the control unit.

[0011] In some embodiments, the hydraulic control system also includes: a hydraulic oil tank, which is connected to the oil supply circuit; a main pump, which is arranged on the oil supply circuit and is used to transfer the hydraulic oil in the hydraulic oil tank to the steering power cylinder; an emergency pump, which is arranged on the emergency oil circuit between the oil supply circuit and the hydraulic oil tank, and the emergency oil circuit is used to supply oil to the oil supply circuit in an emergency situation.

[0012] In some embodiments, the hydraulic control system also includes: an emergency valve group, which is arranged on the oil supply line between the main pump and the electronically controlled reversing valve, the emergency valve group is used to detect the hydraulic oil flow in the oil supply line and transmit it to the control unit, and the control unit determines whether the main pump fails based on the control signal sent by the emergency valve group; an accumulator, which is connected to the oil supply line through an emergency branch and is used to supply oil to the oil supply line in an emergency.

[0013] In some embodiments, the emergency valve group includes: a hydraulic oil adjustment component, which is arranged on the oil supply line, and the hydraulic oil adjustment component is used to preferentially supply oil to the accumulator; a flow detection module, which is arranged on the first connecting oil line between the hydraulic oil adjustment component and the electronically controlled reversing valve, and the flow detection module is used to detect the hydraulic oil flow of the first connecting oil line in real time and send a control signal to the control unit.

[0014] In some embodiments, the hydraulic oil adjustment assembly includes: a sequence valve, which is arranged on the oil supply line between the emergency branch and the flow detection module; a first hydraulically controlled reversing valve, wherein the two control oil ports of the first hydraulically controlled reversing valve are respectively connected to the emergency branch and the oil line between the sequence valve and the flow detection module, and the first hydraulically controlled reversing valve is connected to the control oil port of the sequence valve. When the pressure of the control oil port of the first hydraulically controlled reversing valve is greater than the first preset pressure, the first hydraulically controlled reversing valve controls the emergency branch to be connected to the control oil port to open the sequence valve.

[0015] In some embodiments, the hydraulic oil adjustment assembly includes: a priority valve, which is arranged on the oil supply line, the oil inlet of the priority valve is connected to the main pump, the non-priority oil port of the priority valve is connected to the emergency branch, and the priority oil port of the priority valve is connected to the electronically controlled reversing valve; a flow detection module, which is arranged on the first connecting oil line between the priority valve and the electronically controlled reversing valve, the flow detection module is used to detect the hydraulic oil flow of the first connecting oil line in real time and send a control signal to the control unit; an overflow valve, which is arranged on the third connecting oil line between the emergency branch and the hydraulic oil tank.

[0016] In some embodiments, the flow detection module includes: a second hydraulically controlled reversing valve, including a normal working position and an abnormal working position, when the second hydraulically controlled reversing valve is in the abnormal working position, the second hydraulically controlled reversing valve is cut off, and when the second hydraulically controlled reversing valve is in the normal working position, the second hydraulically controlled reversing valve connects the first connecting oil circuit and the emergency branch; a throttle valve, arranged on the first connecting oil circuit, the two ends of the throttle valve are respectively connected to the priority oil ports of the electric control reversing valve and the priority valve, and the two control oil ports of the second hydraulically controlled reversing valve are respectively connected to the two ends of the throttle valve, and when the pressure difference between the two ends of the throttle valve is greater than a fourth preset pressure, the second hydraulically controlled reversing valve switches to the abnormal working position; a signal transmission unit, installed on the hydraulically controlled reversing valve and used to send a control signal to the control unit when the second hydraulically controlled reversing valve is in the normal position.

[0017] In some embodiments, the emergency valve group also includes: a one-way valve, which is arranged on the emergency branch line and is used to unidirectionally guide the flow direction of the oil supply circuit to the accumulator; a switch valve, which is arranged on the second connecting oil circuit between the accumulator and the emergency oil circuit, and the control oil port of the switch valve is connected to the oil circuit between the switch valve and the emergency oil circuit. When the pressure received by the control oil port of the switch valve is greater than the second preset pressure, the switch valve is turned on.

[0018] A third aspect of the present application provides a control method for a steering mechanism, which is applied to the above-mentioned steering mechanism. The control method includes: determining the turning angle of the axle when it is determined that the driver does not place both hands on the steering wheel; switching the working position of the electronically controlled reversing valve according to the turning angle so that the steering power cylinder drives the axle to return to the center position, thereby driving the steering wheel to return to the center position.

[0019] A third aspect of the present application provides a working machine comprising the above-mentioned steering mechanism.

[0020] In the above-mentioned technical solution, the steering mechanism includes an axle, a steering wheel, and a hydraulic control system. The hydraulic control system includes a power steering cylinder, an oil supply circuit, an electronically controlled reversing valve, and a control unit. The power steering cylinder is used to drive the axle to perform steering operations and provide driving torque for wheel steering. The oil supply circuit is used to supply oil to the power steering cylinder so that the power steering cylinder can extend and retract to drive the axle. The electronically controlled reversing valve is disposed on the oil supply circuit. The two working oil ports of the electronically controlled reversing valve are respectively connected to the rod chamber and rodless chamber of the power steering cylinder. Switching the operating position of the electronically controlled reversing valve controls the direction of hydraulic oil flowing into the power steering cylinder, thereby controlling whether the power steering cylinder extends or remains stationary. The control unit is communicatively connected to the electronically controlled reversing valve and is configured to: determine the turning angle of the axle when it is determined that the driver is not placing both hands on the steering wheel; and switch the operating position of the electronically controlled reversing valve based on the turning angle to enable the power steering cylinder to drive the axle to return to the center position, thereby driving the steering wheel to return to the center position. With the aforementioned steering mechanism, when the driver is not steering (i.e., without both hands on the steering wheel), the hydraulic control system of the present application can automatically drive the axle to return to center, thereby driving the steering wheel to center. This allows the vehicle to automatically maintain straight driving without the need for manual driver operation, thereby improving driving safety and comfort. Furthermore, the steering mechanism of the present application has a simple structure, is easy to implement, and has high reliability and practicality, making it widely applicable to various work machines.

[0021] Other features and advantages of the embodiments of the present application will be described in detail in the subsequent detailed description. BRIEF DESCRIPTION OF THE DRAWINGS

[0022] The accompanying drawings are used to provide a further understanding of the embodiments of the present application and constitute a part of the specification. Together with the following specific embodiments, they are used to explain the embodiments of the present application, but do not constitute a limitation on the embodiments of the present application. For those skilled in the art, other drawings can be obtained based on the structures shown in these drawings without inventive work. In the drawings: Figure 1 A hydraulic principle diagram of a hydraulic control system provided according to the first embodiment of the present application; Figure 2 A partial hydraulic principle diagram of a hydraulic control system provided according to a second embodiment of the present application; Figure 3 This is a partial hydraulic principle diagram of a hydraulic control system provided according to the third embodiment of the present application.

[0023] Description of Reference Numerals 10 Power steering cylinder 20 Electric control reversing valve 30 Main control valve 40 hydraulic oil tank 50 Main pump 60 Emergency Pump 70 Emergency valve group 71 flow detection module 711 Second hydraulically controlled reversing valve 712 Throttle Valve 721 Sequence Valve 722 First hydraulically controlled reversing valve 73 Check valve 74 On / Off Valve 75 Priority valve 76 Relief Valve 80 Accumulator 90 Steering Wheel 100 axles 110 connecting rod mechanism L1 oil supply line L2 emergency oil line L3 emergency branch L4 first connecting oil line L5 Second connecting oil line L6 Third connecting oil line DETAILED DESCRIPTION The following describes the specific embodiments of the present application in detail with reference to the accompanying drawings. It should be understood that the specific embodiments described herein are only used to illustrate and explain the present application and are not intended to limit the present application.

[0024] The steering mechanism according to the present application is described below with reference to the accompanying drawings. Figure 1 , which is a hydraulic principle diagram of a hydraulic control system provided according to the first embodiment of the present application.

[0025] The steering mechanism provided in the embodiment of the present application includes an axle 100, a steering wheel 90, and a hydraulic control system. The hydraulic control system includes: The power steering cylinder 10 is used to drive the axle 100 to perform steering operations.

[0026] The oil supply passage L1 is used to supply oil to the power steering cylinder 10 .

[0027] The electronically controlled reversing valve 20 is provided on the oil supply line L1 , and two working oil ports of the electronically controlled reversing valve 20 are respectively connected to the rod chamber and the rodless chamber of the power steering cylinder 10 .

[0028] A control unit (not shown) is in communication with the electronically controlled reversing valve 20 and is configured to: determine the turning angle of the vehicle axle 100 when it is determined that the driver has not placed both hands on the steering wheel 90; switch the working position of the electronically controlled reversing valve 20 according to the turning angle, so that the steering power cylinder 10 drives the vehicle axle 100 to return to the center, thereby driving the steering wheel 90 to return to the center.

[0029] The steering mechanism typically includes an axle 100, a steering wheel 90, and a hydraulic control system. The axle 100 is a mechanical structure that drives the running wheels in a certain direction. The steering wheel 90 generates control signals that control the axle 100 and the hydraulic control system to perform steering operations. The hydraulic control system includes a reversing valve and a power steering cylinder 10. The power steering cylinder 10 drives the axle 100 to steer, and the reversing valve of the hydraulic control system controls the flow direction of hydraulic oil within the hydraulic control system. The control unit of the hydraulic control system receives signals from the steering wheel 90 and controls the power steering cylinder 10 to steer the axle 100. The oil supply line L1 supplies oil to the power steering cylinder 10 to ensure its normal operation. The two working chambers of the power steering cylinder 10 are connected to the two working oil ports of the electronically controlled reversing valve 20, respectively. The electronically controlled reversing valve 20 can switch its operating position, thereby changing the direction of the hydraulic oil flowing into the power steering cylinder 10, enabling the power steering cylinder 10 to extend or retract, or remain stationary, thereby controlling the steering of the axle 100. When the driver's hands are not on the steering wheel 90, the control unit automatically detects the turning angle of the axle 100 and switches the operating position of the electronically controlled reversing valve 20 based on the turning angle, causing the steering cylinder 10 to drive the axle 100 to return to the center position, thereby driving the steering wheel 90 to return to the center position. This design automatically returns the axle 100 to the center position without the driver's manual operation, allowing the vehicle to maintain straight driving, thereby improving driving safety and comfort. In one specific embodiment, a linkage mechanism 110 is connected between the axle 100 and the steering wheel 90. When the axle 100 returns to the center position, it can also drive the steering wheel 90 to return to the center position.

[0030] In a specific embodiment, Figure 1 As shown, there are two steering power cylinders 10, each used to control the synchronous steering of the running wheels on both sides. When one of the steering power cylinders 10 performs an extension operation, the other steering power cylinder 10 performs a contraction operation to enable the left and right running wheels to steer synchronously.

[0031] In one embodiment, Figure 1As shown, the electronically controlled reversing valve 20 includes an intermediate cutoff position, a forward conducting position, and a reverse conducting position. The control unit is further configured to: when it is determined that the driver has not placed both hands on the steering wheel 90 and the axle 100 has a turning angle, control the electronically controlled reversing valve 20 to switch to the forward conducting position or the reverse conducting position to drive the piston rod of the power steering cylinder 10 to extend and retract; when it is determined that the driver has not placed both hands on the steering wheel 90 and the axle 100 is in the return direction, control the electronically controlled reversing valve 20 to switch to the intermediate cutoff position to cut off the oil supply line L1 and the power steering cylinder 10.

[0032] To enable the steering cylinder 10 to extend and retract, and to maintain its stationary state, the electronically controlled reversing valve 20 has three operating positions: an intermediate blocking position, a forward conducting position, and a reverse conducting position. Normally, the electronically controlled reversing valve 20 is in the intermediate blocking position, blocking the oil supply line L1 from the steering cylinder 10, and the steering cylinder 10 remains stationary. When the axle 100 requires steering, the control unit determines the steering direction and angle based on control signals from the steering wheel 90 or the turning angle of the axle 100 detected by the angle detection unit. The control unit then switches the electronically controlled reversing valve 20 to the forward conducting position or the reverse conducting position, allowing hydraulic oil in the oil supply line L1 to flow into the rod chamber or rodless chamber of the steering cylinder 10, driving the piston rod of the steering cylinder 10 to extend and retract, thereby causing the axle 100 to perform steering operations. When the axle 100 turns to the preset return angle, the control unit can control the electronically controlled reversing valve 20 to switch back to the intermediate cut-off position, cutting off the oil supply line L1 and the power steering cylinder 10. At this time, the power steering cylinder 10 stops working and the axle 100 remains in the return position.

[0033] In one embodiment, Figure 1As shown, the hydraulic control system also includes a main control valve 30, located on the oil supply line L1 and connected to the steering wheel 90. The main control valve 30 has two working oil ports and two control oil ports. The two working oil ports of the main control valve 30 communicate with the rod chamber and rodless chamber of the power steering cylinder 10, respectively. The two control oil ports of the main control valve 30 communicate with the oil inlet and outlet of the electrically controlled reversing valve 20, respectively. When the steering wheel 90 is stationary or the driver's hands are not on the steering wheel 90, the main control valve 30 connects the oil supply line L1 to the electrically controlled reversing valve 20. As the steering wheel 90 rotates, the main control valve 30 switches its working position, thereby driving the power steering cylinder 10 to extend or retract. When the steering wheel 90 is stationary or the driver's hands are not on the steering wheel 90, the main control valve 30 is in its normal position. Hydraulic oil in the oil supply line L1 flows to the electrically controlled reversing valve 20, and the control unit automatically controls whether the power steering cylinder 10 remains stationary or retracts or retracts. Using the aforementioned hydraulic control system, when the steering wheel 90 is stationary or the driver's hands are not resting on it, the main control valve 30 connects the oil supply line L1 to the electronically controlled reversing valve 20. At this point, the electronically controlled reversing valve 20 switches its operating position based on a control signal from the control unit, enabling the automatic return of the axle 100. This design not only improves steering control accuracy but also enhances driving safety and comfort. The connection between the main control valve 30 and the steering wheel 90 can be electrical or mechanical.

[0034] In one embodiment, the main control valve 30 has a first turning position, a second turning position, and a turn-off position. When the main control valve 30 is in the turn-off position, the oil supply line L1 controlled by the main control valve 30 is in communication with the electronically controlled reversing valve 20. When the main control valve 30 is in either the first or second turning position, the main control valve 30 controls the oil supply line L1 to be in communication with the power steering cylinder 10. For example, if the driver rotates the steering wheel 90 counterclockwise at a certain speed, the steering wheel 90 can adjust the main control valve 30 to be in the first or second turning position, causing the hydraulic oil to actively extend and retract the power steering cylinder 10, increasing the leftward steering angle of the road wheels. If the driver maintains the steering wheel 90 fully turned clockwise, the steering wheel 90 can adjust the main control valve 30 to the turn-off position, maintaining the extended and retracted length of the power steering cylinder 10 and allowing the road wheels to operate at their maximum rightward steering angle. When the main control valve 30 is in the turn-off position, hydraulic oil in supply line L1 can enter the electronically controlled reversing valve 20. The electronically controlled reversing valve 20 further controls the flow of hydraulic oil in supply line L1 to the power steering cylinder 10 or back to the main control valve 30. When the main control valve 30 is in the first or second turning position (i.e., the steering wheel 90 is turning), the main control valve 30 directly controls the flow of hydraulic oil in supply line L1 to the rod chamber or rodless chamber of the power steering cylinder 10, thereby driving the axle 100 to change the steering angle. Using this main control valve 30, the extension and retraction of the power steering cylinder 10 can be precisely controlled according to different steering requirements, thereby achieving precise steering of the axle 100.

[0035] In one embodiment, the steering mechanism further includes a steering wheel 90 detection unit (not shown) communicatively connected to the control unit. The steering wheel 90 detection unit is configured to detect in real time whether the driver has both hands on the steering wheel 90 and transmit a control signal to the control unit. The steering wheel 90 detection unit can detect in real time whether the driver has both hands on the steering wheel 90 and transmit the detection result to the control unit in the form of a control signal. Upon receiving the control signal from the steering wheel 90 detection unit, the control unit can determine whether the driver is operating the steering wheel 90. If the steering wheel 90 detection unit detects that the driver has neither hand on the steering wheel 90, i.e., the driver is not operating the steering wheel 90, the control unit automatically performs centering control on the axle 100. This design enables the vehicle to automatically maintain straight driving even when the driver is not operating the steering wheel 90, preventing the vehicle from deviating from its route due to driver negligence, further improving driving safety and reliability. The steering wheel 90 detection unit can be implemented in various ways. For example, a detection device such as a pressure sensor, infrared sensor, or camera can be provided to detect the state of the steering wheel 90 in real time.

[0036] In one embodiment, the steering mechanism further includes an angle detection unit (not shown) mounted on the axle 100. The angle detection unit is configured to detect the turning angle of the axle 100 and transmit the detected turning angle data to the control unit. The angle detection unit is capable of detecting the turning angle of the axle 100 in real time and transmitting the detected turning angle data to the control unit. After receiving the turning angle data from the angle detection unit, the control unit determines the required operating position of the electronically controlled reversing valve 20 based on the current turning angle and a preset return angle, thereby controlling the extension and retraction of the power steering cylinder 10 and achieving automatic return of the axle 100. This design enables precise control of the steering angle of the axle 100, enabling the vehicle to more accurately maintain a straight-line driving state and improving driving stability and comfort. The specific implementation of the angle detection unit can also be diverse. For example, a rotary encoder, angle sensor, or other detection device can be provided to achieve real-time detection of the turning angle of the axle 100.

[0037] In one embodiment, Figure 1 As shown, the hydraulic control system also includes a hydraulic oil tank 40, a main pump 50, and an emergency pump 60. The hydraulic oil tank 40 is connected to the oil supply line L1. The main pump 50 is located on the oil supply line L1 and is used to transfer hydraulic oil from the hydraulic oil tank 40 to the power steering cylinder 10. The emergency pump 60 is located on the emergency oil line L2 between the oil supply line L1 and the hydraulic oil tank 40. The emergency oil line L2 is used to supply oil to the oil supply line L1 in emergency situations. The hydraulic oil tank 40 can store hydraulic oil and provide hydraulic oil to the oil supply line L1. The main pump 50 is located on the oil supply line L1 and is used to transfer hydraulic oil from the hydraulic oil tank 40 to the power steering cylinder 10 under normal operating conditions, driving the power steering cylinder 10 to extend and retract, thereby driving the axle 100 to perform steering operations. The emergency pump 60 is located on the emergency oil line L2 between the oil supply line L1 and the hydraulic oil tank 40. Normally, the emergency oil line L2 is closed. Only in emergency situations, such as when the main pump 50 fails or the oil supply line L1 is partially interrupted, is the emergency oil line L2 opened? At this point, the emergency pump 60 begins to operate, transferring hydraulic oil from the hydraulic oil tank 40 to the oil supply line L1 via the emergency oil line L2 to ensure the proper functioning of the power steering cylinder 10. This design improves the reliability and stability of the hydraulic control system, enabling the vehicle to maintain normal steering function in emergency situations, further enhancing driving safety and reliability.

[0038] In one embodiment, Figure 1As shown, the hydraulic control system also includes an emergency valve group 70 and an accumulator 80. The emergency valve group 70 is located on the oil supply line L1 between the main pump 50 and the electronically controlled reversing valve 20. The emergency valve group 70 is used to detect the hydraulic oil flow in the oil supply line L1 and transmit it to the control unit. The control unit determines whether the main pump 50 has failed based on the control signal sent by the emergency valve group 70. The accumulator 80 is connected to the oil supply line L1 via the emergency branch line L3 and is used to provide emergency oil to the oil supply line L1. With the above-mentioned emergency valve group 70 and accumulator 80, the emergency valve group 70 can monitor the hydraulic oil flow in the oil supply line L1 in real time and transmit the monitored data to the control unit in the form of a control signal. After receiving the control signal from the emergency valve group 70, the control unit can analyze and determine whether the main pump 50 is operating normally. If the emergency valve group 70 detects an abnormal hydraulic oil flow in the oil supply line L1, such as too little flow or no flow, the control unit can determine that the main pump 50 has failed or malfunctioned. At this time, the control unit will immediately trigger the emergency mechanism and open the emergency branch L3, so that the hydraulic oil in the accumulator 80 can quickly flow into the oil supply line L1 to ensure that the steering power cylinder 10 can still obtain sufficient hydraulic oil supply in an emergency situation, thereby maintaining normal steering function. The accumulator 80, as an energy storage device, can provide emergency oil supply to the oil supply line L1 in an emergency, ensuring the normal operation of the steering power cylinder 10. If the emergency pump 60 is relied upon alone to supply oil to the oil supply line L1, the emergency pump 60 needs to be started quickly at high power in a short period of time, which can easily cause damage to the emergency pump 60 and its electronic control components or performance degradation. The accumulator 80 can quickly release the stored energy in an emergency situation and provide a stable supply of hydraulic oil to the oil supply line L1, thereby improving the emergency response capability and reliability of the hydraulic control system.

[0039] In one embodiment, Figure 1As shown, the emergency valve assembly 70 includes a hydraulic oil adjustment assembly and a flow detection module 71. The hydraulic oil adjustment assembly is located on the oil supply line L1 and is used to prioritize oil supply to the accumulator 80. The flow detection module 71 is located on the first connecting oil line L4 between the hydraulic oil adjustment assembly and the electronically controlled reversing valve 20. The flow detection module 71 is used to detect the hydraulic oil flow in the oil supply line L1 in real time and send a control signal to the control unit. The hydraulic oil adjustment assembly distributes the hydraulic oil flow in the oil supply line L1. During normal operation, if the accumulator 80 is under-charged, the hydraulic oil adjustment assembly prioritizes oil supply to the accumulator 80 to ensure sufficient energy storage. The flow detection module 71 is located on the first connecting oil line L4 between the hydraulic oil adjustment assembly and the electronically controlled reversing valve 20 and is used to detect the hydraulic oil flow in the first connecting oil line L4 in real time and provide feedback of the control signal to the control unit. Based on the control signal from the flow detection module 71, the control unit can monitor the hydraulic oil flow status in the oil supply line L1 in real time. If flow detection module 71 detects an abnormal decrease or interruption in the hydraulic oil flow in supply line L1, the control unit quickly determines that the main pump 50 has failed or that supply line L1 has a fault, and immediately activates the emergency response mechanism. Accumulator 80 is opened to supply oil to supply line L1, and emergency branch line L3 is simultaneously opened, allowing the hydraulic oil in accumulator 80 to be quickly replenished to supply line L1, ensuring that the power steering cylinder 10 maintains a stable supply of hydraulic oil in emergency situations. This design not only improves the emergency response speed of the hydraulic control system but also ensures the normal operation of the power steering cylinder 10 in emergency situations, further enhancing driving safety and reliability.

[0040] In one embodiment, Figure 1 As shown, the hydraulic oil adjustment assembly includes a sequence valve 721 and a first hydraulically controlled reversing valve 722. The sequence valve 721 is disposed on the oil supply line L1 between the emergency branch L3 and the flow detection module 71. The two control oil ports of the first hydraulically controlled reversing valve 722 are connected to the emergency branch L3 and the oil circuit between the sequence valve 721 and the flow detection module 71, respectively. The first hydraulically controlled reversing valve 722 is in communication with the control oil port of the sequence valve 721. When the pressure at the control oil port of the first hydraulically controlled reversing valve 722 exceeds a first preset pressure, the first hydraulically controlled reversing valve 722 controls the emergency branch L3 to be in communication with the control oil port, thereby opening the sequence valve 721. The sequence valve 721 is a hydraulic valve that can automatically open or close based on changes in pressure at its control oil port. In the hydraulic control system, the sequence valve 721 is arranged on the oil supply line L1 between the emergency branch L3 and the flow detection module 71. It can be used to adjust the flow direction of the hydraulic oil flowing out of the main pump 50. When the storage pressure of the accumulator 80 is low, the sequence valve 721 can give priority to supplying oil to the accumulator 80.

[0041] When the stored pressure in the accumulator 80 reaches a preset threshold, the pressure in the emergency branch line L3 is transmitted to the control port of the first hydraulically controlled reversing valve 722, switching the first hydraulically controlled reversing valve 722 from its normal position to its abnormal position. This in turn causes hydraulic oil to flow to the control port of the sequence valve 721, opening the sequence valve 721 and allowing the hydraulic oil in the oil supply line L1 to flow to the first flow detection module 71. Furthermore, when the steering wheel 90 is moved, the oil pressure in the oil circuit between the sequence valve 721 and the flow detection module 71 increases. This hydraulic oil pressure is transmitted to the control port of the first hydraulically controlled reversing valve 722, switching the first hydraulically controlled reversing valve 722 to its working position and opening the sequence valve 721, allowing the oil supply line L1 to supply oil to the power steering cylinder 10. Using this hydraulic adjustment assembly, when the steering wheel 90 is not moved, the accumulator 80 is prioritized for energy storage. Once energy storage is complete, the sequence valve 721 is opened to supply oil to the power steering cylinder 10. When the steering wheel 90 is moved, the sequence valve 721 can be directly opened to connect the oil supply path L1 , thereby preventing the occurrence of insufficient pressure in the power steering cylinder 10 .

[0042] In one embodiment, Figure 2 The figure shows a partial hydraulic principle diagram of a hydraulic control system according to a second embodiment of the present application. The hydraulic oil adjustment assembly further includes: a priority valve 75, a flow detection module 71, and a relief valve 76. The priority valve 75 is arranged on the oil supply line L1. The oil inlet of the priority valve 75 is connected to the main pump 50. The non-priority oil port of the priority valve 75 is connected to the emergency branch line L3. The priority oil port of the priority valve 75 is connected to the flow detection module 71. The flow detection module 71 is arranged on the first connecting oil line L4 between the priority valve 75 and the electronically controlled reversing valve 20. The flow detection module 71 is used to detect the hydraulic oil flow in the first connecting oil line L4 in real time and send a control signal to the control unit. The relief valve 76 is arranged on the third connecting oil line L6 between the emergency branch line L3 and the hydraulic oil tank 40.

[0043] The priority valve 75 is a valve that can automatically adjust the flow direction of hydraulic oil according to changes in hydraulic oil pressure. In the embodiment of the present application, the priority valve 75 and the relief valve 76 are used to replace the sequence valve 721 and the first hydraulically controlled reversing valve 722 in the above embodiment. In the hydraulic control system, the priority valve 75 is arranged on the oil supply circuit L1, its oil inlet is connected to the main pump 50, the non-priority oil port is connected to the emergency branch L3, and the priority oil port is connected to the flow detection module 71. Under normal operating conditions, the main pump 50 pumps hydraulic oil to the oil supply circuit L1. The priority valve 75, based on changes in hydraulic oil pressure, preferentially supplies hydraulic oil to the flow detection module 71 and the electronically controlled reversing valve 20 to prioritize the normal operation of the power steering cylinder 10. After the hydraulic oil pressure on the first connecting oil circuit L4 is greater than the third preset pressure, the priority valve 75 controls the main pump 50 to connect with the accumulator 80 to store energy in the accumulator 80. To ensure stable hydraulic oil pressure in the emergency branch line L3, a relief valve 76 is installed on the third connecting oil line L6 between the emergency branch line L3 and the hydraulic oil tank 40. When the hydraulic oil pressure in the emergency branch line L3 exceeds a preset pressure threshold, the relief valve 76 automatically opens, returning excess hydraulic oil to the hydraulic oil tank 40, thereby maintaining the hydraulic oil pressure in the emergency branch line L3 within a preset range. This design not only improves the emergency response speed of the hydraulic control system but also ensures that the accumulator 80 has sufficient energy to meet emergency needs.

[0044] In one embodiment, Figure 3Figure 2 shows a partial hydraulic principle diagram of a hydraulic control system according to a third embodiment of the present application. The flow detection module 71 includes a second hydraulically controlled directional valve 711, a throttle valve 712, and a signal transmission unit. The second hydraulically controlled directional valve 711 has a normal operating position and an abnormal operating position. When in the abnormal operating position, the second hydraulically controlled directional valve 711 is closed. In the normal operating position, the second hydraulically controlled directional valve 711 connects the first connecting oil line L4 and the emergency branch line L3. The throttle valve 712 is provided on the first connecting oil line L4. Its two ends are connected to the priority oil ports of the electronically controlled directional valve 20 and the priority valve 75, respectively. The two control oil ports of the second hydraulically controlled directional valve 711 are connected to the two ends of the throttle valve 712, respectively. When the pressure difference across the throttle valve 712 exceeds a fourth preset pressure, the second hydraulically controlled directional valve 711 is in the abnormal operating position. The signal transmission unit is mounted on the hydraulically controlled reversing valve and is used to send a control signal to the control unit when the second hydraulically controlled reversing valve 711 is in the normal position. When the main pump 50 is operating normally, the pressure differential across the throttle valve 712 is large, and the second hydraulically controlled reversing valve 711 is in the abnormal operating position. The hydraulic oil from the main pump 50 flows through the throttle valve 712 to supply the power steering cylinder 10, and the accumulator 80 is unable to supply oil to the power steering cylinder 10. If the main pump 50 fails or the oil supply line L1 becomes abnormal, the pressure differential across the throttle valve 712 decreases, and the second hydraulically controlled reversing valve 711 switches to the normal operating position. The second hydraulically controlled reversing valve 711 then opens the first connecting oil line L4 and the emergency branch line L3, allowing the residual hydraulic oil in the main pump 50, the emergency branch line L3, and the emergency oil line L2 to jointly supply the oil supply line L1. When detecting that the second hydraulically controlled reversing valve 711 is in the normal working position, the signal transmission unit can send a control signal to the control unit so that the control unit can start the emergency pump 60 for emergency oil supply.

[0045] In one embodiment, Figure 1 and Figure 2As shown, the emergency valve assembly 70 further includes a one-way valve 73 and an on-off valve 74. The one-way valve 73 is disposed on the emergency branch line L3 and is used to unidirectionally direct the flow of hydraulic oil from the oil supply line L1 to the accumulator 80. The on-off valve 74 is disposed on the second connecting oil line L5 between the accumulator 80 and the emergency oil line L2. The control oil port of the on-off valve 74 communicates with the oil line between the on-off valve 74 and the emergency oil line L2. When the pressure received by the control oil port of the on-off valve 74 exceeds a second preset pressure, the on-off valve 74 is opened. The one-way valve 73 prevents hydraulic oil from flowing back from the accumulator 80 to the oil supply line L1 when the main pump 50 is operating normally, ensuring that the hydraulic oil in the accumulator 80 can be effectively utilized. On-off valve 74 controls the flow between accumulator 80 and emergency oil circuit L2. When the pressure at the control port of on-off valve 74 exceeds a second preset pressure, indicating that the system is in an emergency state, on-off valve 74 opens, allowing the hydraulic oil in accumulator 80 to be quickly replenished to supply oil circuit L1 via emergency oil circuit L2. This design further enhances the emergency response capability of the hydraulic control system, ensuring that the vehicle can maintain normal steering function in emergency situations.

[0046] In one embodiment, a control method for a steering mechanism is provided, which is applied to the above-mentioned steering mechanism. The control method includes: determining the turning angle of the axle 100 when it is determined that the driver does not place both hands on the steering wheel 90; switching the working position of the electronically controlled reversing valve 20 according to the turning angle, so that the steering power cylinder 10 drives the axle 100 to return to the center, thereby driving the steering wheel 90 to return to the center.

[0047] In one embodiment, a working machine is provided, comprising the above-mentioned steering mechanism.

[0048] In the description of this application, it should be understood that the terms "first" and "second" are used for descriptive purposes only and should not be understood to indicate or imply relative importance or implicitly specify the number of technical features indicated. Therefore, a feature defined as "first" or "second" may explicitly or implicitly include at least one of such features. In the description of this application, "plurality" means at least two, for example, two, three, etc., unless otherwise specifically defined.

[0049] In this application, unless otherwise specified or limited, the terms "installed," "connected," "connect," "fixed," etc. should be understood in a broad sense. For example, they can refer to fixed connection, detachable connection, or integration; mechanical connection, electrical connection, or communication; direct connection or indirect connection through an intermediate medium; internal communication between two elements or interaction between two elements, unless otherwise specified. Those skilled in the art will understand the specific meanings of the above terms in this application based on specific circumstances.

[0050] In the description of this specification, the description with reference to the terms "one embodiment", "some embodiments", "example", "specific example", or "some examples" means that the specific features, structures, materials or characteristics described in conjunction with the embodiment or example are included in at least one embodiment or example of the present application. In this specification, the schematic representations 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 any one or more embodiments or examples in a suitable manner. In addition, those skilled in the art can combine and combine different embodiments or examples described in this specification and features of different embodiments or examples without contradiction.

[0051] Although the embodiments of the present application have been shown and described above, it can be understood that the above embodiments are exemplary and cannot be understood as limitations on the present application. Ordinary technicians in this field can change, modify, replace and modify the above embodiments within the scope of the present application.

Claims

1. A steering mechanism, characterized in that: The steering mechanism comprises an axle (100), a steering wheel (90) and a hydraulic control system, wherein the hydraulic control system comprises: A steering power cylinder (10) for driving the axle (100) to perform a steering operation; An oil supply circuit (L1) for supplying oil to the power steering cylinder (10); An electrically controlled reversing valve (20) is provided on the oil supply line (L1), and two working oil ports of the electrically controlled reversing valve (20) are respectively connected to the rod chamber and the rodless chamber of the steering power cylinder (10); A control unit is in communication with the electrically controlled reversing valve (20) and is configured to: determining the turning angle of the axle (100) when it is determined that the driver does not place both hands on the steering wheel (90); The working position of the electrically controlled reversing valve (20) is switched according to the turning angle, so that the steering power cylinder (10) drives the axle (100) to return to the center, thereby driving the steering wheel (90) to return to the center.

2. The steering mechanism according to claim 1, characterized in that: The electrically controlled reversing valve (20) comprises an intermediate cut-off position, a forward conducting position and a reverse conducting position, and the control unit is further configured as follows: When it is determined that the driver has not placed both hands on the steering wheel (90) and the axle (100) has a turning angle, the electrically controlled reversing valve (20) is controlled to switch to the forward conducting position or the reverse conducting position to drive the piston rod of the steering power cylinder (10) to extend and retract; When it is determined that the driver has not placed both hands on the steering wheel (90) and the axle (100) is in the return direction, the electrically controlled reversing valve (20) is controlled to switch to the intermediate cut-off position, thereby cutting off the oil supply circuit (L1) and the steering assist oil cylinder (10).

3. The steering mechanism according to claim 1, characterized in that: The hydraulic control system further comprises: A main control valve (30) is provided on the oil supply circuit (L1) and is connected to the steering wheel (90). The main control valve (30) has two working oil ports and two control oil ports. The two working oil ports of the main control valve (30) are respectively connected to the rod chamber and the rodless chamber of the steering power cylinder (10). The two control oil ports of the main control valve (30) are respectively connected to the oil inlet and the oil outlet of the electric control reversing valve (20). When the steering wheel (90) is stationary or the driver does not place both hands on the steering wheel (90), the main control valve (30) connects the oil supply circuit (L1) to the electric control reversing valve (20).

4. The steering mechanism according to claim 3, characterized in that: The main control valve (30) includes a first turning position, a second turning position, and a turning stop position. When the main control valve (30) is in the turning stop position, the oil supply circuit (L1) controlled by the main control valve (30) is connected to the electronically controlled reversing valve (20); when the main control valve (30) is in the first turning position or the second turning position, the main control valve (30) controls the oil supply circuit (L1) to be connected to the steering assist cylinder (10).

5. The steering mechanism according to any one of claims 1 to 4, characterized in that: The steering mechanism further comprises a steering wheel (90) detection unit communicatively connected to the control unit, the steering wheel (90) detection unit being used to detect in real time whether the driver places both hands on the steering wheel (90) and to send a control signal to the control unit.

6. The steering mechanism according to any one of claims 1 to 4, characterized in that: The steering mechanism further comprises an angle detection unit mounted on the axle (100), wherein the angle detection unit is used to detect the turning angle of the axle (100) and transmit the detected angle to the control unit.

7. The steering mechanism according to claim 1, characterized in that: The hydraulic control system further comprises: a hydraulic oil tank (40) in communication with the oil supply line (L1); a main pump (50) disposed on the oil supply line (L1) and used to transmit the hydraulic oil in the hydraulic oil tank (40) to the steering power cylinder (10); An emergency pump (60) is provided on an emergency oil circuit (L2) between the oil supply circuit (L1) and the hydraulic oil tank (40), and the emergency oil circuit (L2) is used to supply oil to the oil supply circuit (L1) in an emergency situation.

8. The steering mechanism according to claim 7, characterized in that: The hydraulic control system further comprises: an emergency valve group (70) disposed on the oil supply line (L1) between the main pump (50) and the electrically controlled reversing valve (20), the emergency valve group (70) being used to detect the hydraulic oil flow rate of the oil supply line (L1) and transmit the flow rate to the control unit, the control unit determining whether the main pump (50) has failed based on a control signal sent by the emergency valve group (70); An accumulator (80) is connected to the oil supply circuit (L1) via an emergency branch circuit (L3) and is used to supply oil to the oil supply circuit (L1) in an emergency.

9. The steering mechanism according to claim 8, characterized in that: The emergency valve group (70) comprises: a hydraulic oil adjustment component, disposed on the oil supply circuit (L1), the hydraulic oil adjustment component being used to preferentially supply oil to the accumulator (80); A flow detection module (71) is provided on the first connecting oil circuit (L4) between the hydraulic oil adjustment assembly and the electrically controlled reversing valve (20), and the flow detection module (71) is used to detect the hydraulic oil flow of the first connecting oil circuit (L4) in real time and send the control signal to the control unit.

10. The steering mechanism according to claim 9, characterized in that: The hydraulic oil adjustment assembly includes: A sequence valve (721) is provided on the oil supply line (L1) between the emergency branch line (L3) and the flow detection module (71); A first hydraulically controlled reversing valve (722), wherein two control oil ports of the first hydraulically controlled reversing valve (722) are respectively connected to the emergency branch (L3) and the oil circuit between the sequence valve (721) and the flow detection module (71); the first hydraulically controlled reversing valve (722) is connected to the control oil port of the sequence valve (721); when the pressure of the control oil port of the first hydraulically controlled reversing valve (722) is greater than a first preset pressure, the first hydraulically controlled reversing valve (722) controls the emergency branch (L3) to be connected to the control oil port, so that the sequence valve (721) is opened.

11. The steering mechanism according to claim 8, characterized in that: The emergency valve group (70) comprises: a priority valve (75) provided on the oil supply line (L1), wherein the oil inlet of the priority valve (75) is in communication with the main pump (50), the non-priority oil port of the priority valve (75) is in communication with the emergency branch line (L3), and the priority oil port of the priority valve (75) is in communication with the electrically controlled reversing valve (20); a flow detection module (71), provided on the first connecting oil circuit (L4) between the priority valve (75) and the electrically controlled reversing valve (20), the flow detection module (71) being used to detect the hydraulic oil flow of the first connecting oil circuit (L4) in real time and to send the control signal to the control unit; The overflow valve (76) is provided on the third connecting oil circuit (L6) between the emergency branch circuit (L3) and the hydraulic oil tank (40).

12. The steering mechanism according to claim 11, characterized in that: The flow detection module (71) includes: The second hydraulically controlled reversing valve (711) includes a normal working position and an abnormal working position. When the second hydraulically controlled reversing valve (711) is in the abnormal working position, the second hydraulically controlled reversing valve (711) is cut off. When the second hydraulically controlled reversing valve (711) is in the normal working position, the second hydraulically controlled reversing valve (711) connects the first connecting oil circuit (L4) and the emergency branch circuit (L3). A throttle valve (712) is provided on the first connecting oil circuit (L4), the two ends of the throttle valve (712) are respectively connected to the priority oil ports of the electric-controlled reversing valve (20) and the priority valve (75), and the two control oil ports of the second hydraulic-controlled reversing valve (711) are respectively connected to the two ends of the throttle valve (712). When the pressure difference between the two ends of the throttle valve (712) is greater than a fourth preset pressure, the second hydraulic-controlled reversing valve (711) switches to an abnormal working position; A signal transmission unit is installed on the hydraulically controlled reversing valve and is used to send the control signal to the control unit when the second hydraulically controlled reversing valve (711) is in a normal position.

13. The steering mechanism according to any one of claims 8 to 11, characterized in that: The emergency valve assembly (70) further comprises: a one-way valve (73) provided on the emergency branch (L3) and used for unidirectionally directing the flow direction from the oil supply line (L1) to the accumulator (80); The switch valve (74) is provided on the second connecting oil circuit (L5) between the accumulator (80) and the emergency oil circuit (L2); the control oil port of the switch valve (74) is connected to the oil circuit between the switch valve (74) and the emergency oil circuit (L2); when the pressure received by the control oil port of the switch valve (74) is greater than a second preset pressure, the switch valve (74) is turned on.

14. A method for controlling a steering mechanism, characterized in that: Applied to the steering mechanism according to any one of claims 1 to 13, the control method comprises: determining the turning angle of the axle (100) when it is determined that the driver does not place both hands on the steering wheel (90); The working position of the electrically controlled reversing valve (20) is switched according to the turning angle, so that the steering power cylinder (10) drives the axle (100) to return to the center, thereby driving the steering wheel (90) to return to the center.

15. A working machine, characterized in that: The working machine includes the steering mechanism according to any one of claims 1 to 13.

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