Three-shaft unmanned transport vehicle steering system and three-shaft unmanned transport vehicle

Abstract

The utility model discloses a steering system of a three-shaft unmanned transport vehicle and the three-shaft unmanned transport vehicle. The three-shaft unmanned transport vehicle steering system comprises three steering control loops, a steering angle sensor, a first filter, a one-way valve B, an electric oil pump, a second filter, a one-way valve C, a redundant oil pump, an oil tank and a control module, wherein each steering control loop is composed of an electric control hydraulic valve, a one-way valve A, an energy accumulator and a stop valve. According to the three-axle unmanned transport vehicle steering system, the three axles are controlled to steer through the three steering control loops respectively, three-axle independent control can be achieved, and multiple steering modes can be supported; meanwhile, valve blockage can be reduced, manual steering control is carried out during vehicle moving, and the redundancy performance of the system is improved; compared with an existing three-axis steering control loop, the number of components is small, and the cost of the steering control loop is reduced.

Description

Technical Field

[0001] The utility model relates to the technical field of steering of unmanned transport vehicles, in particular to a three-axle unmanned transport vehicle steering system and a three-axle unmanned transport vehicle. Background Art

[0002] The steering system of the existing three-axle vehicle is shown in a hydraulic drive system of a three-axle unmanned vehicle disclosed in a Chinese patent application with the application number CN202211532845.6. It sets multiple hydraulic motors / pumps for control, multiple proportional valves and multiple solenoid valves to jointly control the three-axle steering. The steering control is complex, there are many components, and the manufacturing cost is high. In addition, when the hydraulic motor / pump of the vehicle fails, the steering system cannot work properly. When using a trailer or other device to move the vehicle, the trailer etc. need the wheels to be straightened or assisted steering to facilitate the normal movement of the vehicle. If the wheel angles are not appropriate, it will cause difficulties in towing the trailer, and the existing steering system cannot meet the steering requirements during vehicle relocation. Summary of the Utility Model

[0003] To solve the above technical problems, the utility model provides a three-axle unmanned transport vehicle steering system and a three-axle unmanned transport vehicle. Among them, for the three-axle unmanned transport vehicle steering system, the three-axle unmanned transport vehicle is provided with three axles; it is characterized in that: each of the three axles is provided with a steering control circuit and an angle sensor;

[0004] The steering control circuit includes an electro-hydraulic valve, an A check valve, an accumulator, and a stop valve;

[0005] The output end of the electro-hydraulic valve is connected to the steering bridge cylinder of the axle; the input end of the electro-hydraulic valve is connected to the first filter through the A check valve; the stop valve and the accumulator are connected to the connecting oil path between the A check valve and the electro-hydraulic valve;

[0006] The first filter is connected to the fuel tank through a B check valve and an electric oil pump; the oil return ends of the electro-hydraulic valves are all connected to the fuel tank through a second filter;

[0007] The connection node of the first filter and the B check valve is connected to the fuel tank through a C check valve and a redundant oil pump;

[0008] The electro-hydraulic valve, the angle sensor, and the electric oil pump are all communicatively connected to the control module.

[0009] Preferably, an A pressure sensor is provided on the oil path of the accumulator; a B pressure sensor is provided on the first filter; the A pressure sensor and the B pressure sensor are both communicatively connected to the control module.

[0010] Preferably, the A check valve and the A pressure sensor are integrated in a valve block; the valve block communicates with the stop valve and the accumulator.

[0011] Preferably, the first filter and the second filter are both provided with blockage switches; the blockage switches are communicatively connected to the control module.

[0012] Preferably, an oil cooler and a temperature sensor are provided on the oil return end of the steering control circuit and on the oil path of the second filter; the oil cooler and the temperature sensor are both communicatively connected to the control module.

[0013] Preferably, the fuel tank is provided with a liquid level switch; the liquid level switch is communicatively connected to the control module.

[0014] Preferably, the corner sensors are provided at both ends of the axle.

[0015] The present utility model also provides a three-axle unmanned transport vehicle, which adopts the three-axle unmanned transport vehicle steering system described above arbitrarily.

[0016] Preferably, the first axle and the second axle are arranged adjacent to each other; the A check valve and / or the A pressure sensor in the steering control circuit of the first axle and the A check valve and / or the A pressure sensor in the steering control circuit of the second axle are integrated in the same valve block.

[0017] Preferably, the second axle and the third axle are arranged adjacent to each other; the A check valve and / or the A pressure sensor in the steering control circuit of the second axle and the A check valve and / or the A pressure sensor in the steering control circuit of the third axle are integrated in the same valve block.

[0018] The three-axle unmanned transport vehicle steering system provided by the present utility model controls the steering of three axles respectively through three steering control circuits, can achieve three-axle independent control, and can support multiple steering modes; an electric oil pump supplies oil to the three steering control circuits respectively, and the number of electric oil pumps required is small; through the A check valve, the accumulator and the cut-off valve circuit in the steering control circuit, the reaction speed of the steering system is increased; through the first filter and the second filter, the particulate matter in the hydraulic oil is captured and removed, the valve blockage is reduced, and the occurrence of faults is reduced; through the circuit design of the C check valve and the redundant oil pump, manual steering control is convenient during vehicle relocation, and the system redundancy is improved. The three-axle unmanned transport vehicle steering system provided by the embodiments of the present utility model has simple steering control; compared with the existing three-axle steering control circuit, the number of components is reduced, and the cost of the steering control circuit is reduced. Description of the Drawings

[0019] Figure 1 It is a three-axle unmanned transport vehicle steering system diagram provided by the embodiments of the present utility model;

[0020] Wherein: 11, the first axle; 12, the second axle; 13, the third axle; 21, the first angle sensor; 22, the second angle sensor; 23, the third angle sensor; 311, the first electro-hydraulic valve; 312, the first accumulator; 313, the first stop valve; 314, the first A pressure sensor; 315, the first A check valve; 316, the first valve block; 321, the second electro-hydraulic valve; 322, the second accumulator; 323, the second stop valve; 324, the second A pressure sensor; 325, the second A check valve; 326, the second valve block; 331, the third electro-hydraulic valve; 332, the third accumulator; 333, the third stop valve; 334, the third A pressure sensor; 335, the third A check valve; 336, the third valve block; 341, the first filter; 3411, the first blockage switch; 342, the B check valve; 343, the electric oil pump; 344, the B pressure sensor; 351, the C check valve; 352, the redundant oil pump; 36, the fuel tank; 361, the liquid level switch; 371, the second filter; 3711, the second blockage switch; 372, the oil cooler; 373, the temperature sensor; 40, the control module. Detailed implementation manners

[0021] In order to make the technical means, creative features, achieved purposes and functions of the present utility model easy to understand, the present utility model will be further described below in conjunction with specific embodiments. However, the following embodiments are only the preferred embodiments of the present utility model, not all of them. Based on the embodiments in the implementation manners, other embodiments obtained by those skilled in the art without creative efforts all belong to the protection scope of the present utility model. The experimental methods in the following embodiments are all conventional methods unless otherwise specified. The materials, reagents, etc. used in the following embodiments can all be obtained from commercial channels unless otherwise specified.

[0022] In the description of the present utility model, it should be noted that the orientation or positional relationship indicated by the terms "upper", "lower", "inner", "outer", "front end", "rear end", "both ends", "one end", "the other end", etc. is the orientation or positional relationship based on the orientation or positional relationship shown in the drawings. It is only for the convenience of describing the present utility model 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 therefore cannot be understood as a limitation to the present utility model. In addition, the terms "first" and "second" are only used for descriptive purposes and cannot be understood as indicating or implying relative importance.

[0023] In the description of the present utility model, it should be noted that unless otherwise clearly specified and defined, terms such as "installation", "provided with", "connection", etc. shall be understood in a broad sense. For example, "connection" can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be directly connected or indirectly connected through an intermediate medium, and it can be the communication inside two components. For those of ordinary skill in the art, the specific meanings of the above terms in the present utility model can be understood according to specific circumstances.

[0024] As Figure 1 shown, an embodiment of the present utility model provides a steering system for a three-axle unmanned transport vehicle and a three-axle unmanned transport vehicle. Among them, the three-axle unmanned transport vehicle is provided with three axles, namely a first axle 11, a second axle 12, and a third axle 13; the first axle 11 is provided with a first steering control circuit and a first angle sensor 21; the second axle 12 is provided with a second steering control circuit and a second angle sensor 22; the third axle 13 is provided with a third steering control circuit and a third angle sensor 23; the first angle sensor 21, the second angle sensor 22, and the third angle sensor 23 are all arranged at one end of the corresponding axle; the steering axle of the axle is a hydraulic steering axle;

[0025] The first steering control circuit includes a first electro-hydraulic valve 311, a first A check valve 315, a first accumulator 312, and a first stop valve 313; the oil circuit output end of the first electro-hydraulic valve 311 is connected to the steering axle of the first axle 11; the oil circuit input end of the first electro-hydraulic valve 311 is connected to the first A check valve 315; the first stop valve 313 and the first accumulator 312 are connected to the connecting oil circuit between the first A check valve 315 and the first electro-hydraulic valve 311;

[0026] The second steering control circuit includes a second electro-hydraulic valve 321, a second A check valve 325, a second accumulator 322, and a second stop valve 323; the oil circuit output end of the second electro-hydraulic valve 321 is connected to the steering axle of the second axle 12; the oil circuit input end of the second electro-hydraulic valve 321 is connected to the second A check valve 325; the second stop valve 323 and the second accumulator 322 are connected to the connecting oil circuit between the second A check valve 325 and the second electro-hydraulic valve 321;

[0027] The third steering control circuit includes a third electro-hydraulic valve 331, a third A check valve 335, a third accumulator 332, and a third stop valve 333; the oil circuit output end of the third electro-hydraulic valve 331 is connected to the steering axle of the third axle 13; the oil circuit input end of the third electro-hydraulic valve 331 is connected to the third A check valve 335; the third stop valve 333 and the third accumulator 332 are connected to the connecting oil circuit between the third A check valve 335 and the third electro-hydraulic valve 331;

[0028] The first A check valve 315, the second A check valve 325, and the third A check valve 335 are all connected to the output end of the first filter 341; the input end of the first filter 341 is sequentially connected to the fuel tank 36 through a B check valve 342 and an electric oil pump 343;

[0029] The oil return ends of the first electro-hydraulic valve 311, the second electro-hydraulic valve 321, and the third electro-hydraulic valve 331 are all connected to the fuel tank 36 through a second filter 371;

[0030] The oil circuit connection node of the first filter 341 and the B check valve 342 is connected to the fuel tank 36 through a C check valve 351 and a redundant oil pump 352; the first filter 341 is a high-pressure filter;

[0031] The electro-hydraulic valve, the steering angle sensor, and the electric oil pump 343 are all communicatively connected to the control module 40. The steering angle sensor, the steering axle, the electro-hydraulic valve, the accumulator, the stop valve, the pressure sensor, the check valve, the filter, the electric oil pump, and the redundant oil pump can all adopt existing commercial products; the control module 40 is the control center on the driverless vehicle.

[0032] During steering control, the electric oil pump 343 starts to work, sending the hydraulic oil in the fuel tank 36 to each steering control circuit; the control module 40 controls the on-off of each electro-hydraulic valve respectively to independently control the steering of the corresponding axle, and can support multiple steering mode controls; the response speed of the steering system is accelerated through the accumulator and the stop valve circuit in the steering control circuit;

[0033] The first filter 341 and the second filter 371 respectively capture and remove particulate matter from the hydraulic oil entering the steering control circuit and returning to the fuel tank 36, reducing valve blockage and reducing the occurrence of faults;

[0034] The steering system in this embodiment is also equipped with a redundant oil pump 352; the redundant oil pump 352 is replaced by an existing commercial hand-operated oil pump or an electronically controlled oil pump matched with low-pressure drive; when the electric oil pump 343 fails electronically, the redundant oil pump 352 can be started to provide a hydraulic source, and the steering electro-hydraulic valve does not require high-pressure energy to drive, and low-pressure energy can control the opening and closing of the valve, thereby controlling the steering of the system; it is convenient to perform steering control when moving the vehicle and improves system redundancy.

[0035] The steering system of the three-axle unmanned transport vehicle provided by the embodiment of the present utility model controls the steering of three axles through three steering control loops respectively, can achieve three-axis independent control, and supports a variety of steering modes; an electric oil pump 343 supplies oil to the three steering control loops respectively, and the required number of electric oil pumps 343 is small; through the A check valve, accumulator and stop valve loop in the steering control loop, the reaction speed of the steering system is accelerated; through the first filter 341 and the second filter 371, the particulate matter in the hydraulic oil is captured and removed, reducing valve blockage and reducing the occurrence of faults; through the loop design of the C check valve 351 and the redundant oil pump 352, it is convenient to control the steering during vehicle relocation and improves system redundancy. The steering system of the three-axle unmanned transport vehicle provided by the embodiment of the present utility model has simple steering control; compared with the existing three-axle steering control loop, the number of components is reduced, and the cost of the steering control loop is reduced.

[0036] During specific implementation, a first A pressure sensor 314 is provided on the oil path of the first accumulator 312; a second A pressure sensor 324 is provided on the oil path of the second accumulator 322; a third A pressure sensor 334 is provided on the oil path of the third accumulator 332; a B pressure sensor 344 is provided on the first filter 341; the A pressure sensor and the B pressure sensor 344 are both communicatively connected to the control module 40. By cooperating with the above-mentioned steering system through the A pressure sensor and the B pressure sensor 344, the control module 40 can perform reasonable pressure control logic, better save energy; avoid the continuous long-term operation of the oil pump, motor and controller, and improve reliability.

[0037] During specific implementation, the A check valve and the A pressure sensor are integrated in the valve block; the valve block communicates with the stop valve and the accumulator. As Figure 1 shown, the valve block includes a first valve block 316, a second valve block 326 and a third valve block 336; the first valve block 316, the second valve block 326 and the third valve block 336 are respectively integrated with the A check valve and the A pressure sensor in the steering control loop connected thereto; the integrated valve block provides a system oil path interface, which is convenient for system layout and connection.

[0038] During specific implementation, the first filter 341 is provided with a first blockage switch 3411, and the second filter 371 is provided with a second blockage switch 3711; the first blockage switch 3411 and the second blockage switch 3711 are both communicatively connected to the control module 40. When the impurities in the filter are excessive, the control module 40 monitors the oil path blockage situation through the blockage switch, so as to perform system alarm, cleaning and filter element replacement in time.

[0039] During specific implementation, the filter uses an existing filter product with a blockage switch.

[0040] During specific implementation, an oil cooler 372 and a temperature sensor 373 are provided on the oil return line of the steering control circuit and the oil path of the second filter 371; both the oil cooler 372 and the temperature sensor 373 are communicatively connected to the control module 40. When the oil return temperature is too high, the control module 40 can turn on the oil cooler 372 for cooling, preventing problems such as easy thermal degradation of the hydraulic oil, accelerated oxidation of the oil fluid, and change in the viscosity of the oil fluid at high temperatures, and improving the system reliability.

[0041] During specific implementation, the fuel tank 36 is provided with a liquid level switch 361; the liquid level switch 361 is communicatively connected to the control module 40. By monitoring the oil level in the fuel tank through the liquid level switch 361, when the oil level drops below the set high level, the liquid level switch sends a signal to the control module 40 to trigger an alarm or directly shut down the hydraulic pump, preventing the pump from operating without oil or with insufficient oil, thereby avoiding damage to the pump and system failures.

[0042] During specific implementation, the corner sensors are provided at both ends of the axle. The above axle adopts a structure with a single-sided angle sensor on the axle. This structure performs corner fitting control in combination with the corner relationships of the left and right wheels, saving the matching cost while meeting the application requirements. However, when the angle sensor on the axle is damaged, the steering angle detection cannot be performed. In this implementation, by setting redundant corner sensors, when one angle sensor on the axle fails, the control module 40 can start the redundant corner sensor for angle detection, avoiding problems of abnormal steering control caused by abnormal corner sensors and improving the safety performance.

[0043] The present utility model also provides a three-axle unmanned transport vehicle, adopting the three-axle unmanned transport vehicle steering system as described above arbitrarily.

[0044] During specific implementation, when the first axle 11 and the second axle 12 are arranged adjacent to each other; the first A check valve 315 and / or the first A pressure sensor 314 in the steering control circuit of the first axle 11, and the second A check valve 325 and / or the second A pressure sensor set 324 in the steering control circuit of the second axle 12 are integrated in the same valve block; this valve block communicates with the first accumulator 312 and the second accumulator 322.

[0045] When the second axle 12 and the third axle 13 are arranged adjacent to each other; the second A check valve 325 and / or the second A pressure sensor 324 in the steering control circuit of the second axle 12, and the third A check valve 335 and / or the third A pressure sensor 334 in the steering control circuit of the third axle 13 are integrated in the same valve block; this valve block communicates with the second accumulator 322 and the third accumulator 332.

[0046] The length of the oil circuit affects the system response time and pressure drop. However, when the distances between two axles are close, and on the premise of ensuring the normal operation of the hydraulic oil system, integrating the check valves and A pressure sensors of adjacent axles into one valve block can save the cost of the valve block and some pipeline connection costs, thereby reducing the layout cost of the hydraulic system.

[0047] Although the embodiments of the present invention have been shown and described, those of ordinary skill in the art can understand that various changes, modifications, substitutions, and variations can be made to these embodiments without departing from the principle and spirit of the present invention. The scope of the present invention is defined by the appended claims and their equivalents.

Claims

1. A steering system for a three-axle unmanned transport vehicle, wherein the three-axle unmanned transport vehicle is provided with three axles; characterized in that: All three axles are equipped with steering control circuits and steering angle sensors; The steering control circuit includes an electronically controlled hydraulic valve, a one-way valve A, an accumulator, and a stop valve; The output end of the electronically controlled hydraulic valve is connected to the steering bridge cylinder of the axle; the input end of the electronically controlled hydraulic valve is connected to the first filter (341) via the A check valve; the stop valve and the accumulator are connected to the connecting oil path between the A check valve and the electronically controlled hydraulic valve; The first filter (341) is connected to the oil tank (36) via a B check valve (342) and an electric oil pump (343); the oil return end of the electronically controlled hydraulic valve is connected to the oil tank (36) via a second filter (371); The connection node of the first filter (341) and the B check valve (342) is connected to the oil tank (36) via the C check valve (351) and the redundant oil pump (352); The electronically controlled hydraulic valve, the rotation angle sensor, and the electric oil pump (343) are all communicatively connected to the control module (40).

2. The three-axle unmanned transport vehicle steering system according to claim 1, characterized in that: An A pressure sensor is provided on the oil circuit of the accumulator; the first filter (341) is provided with a B pressure sensor (344); the A pressure sensor and the B pressure sensor (344) are both communicatively connected to the control module (40).

3. The three-axle unmanned transport vehicle steering system according to claim 2 is characterized in that: The A one-way valve and the A pressure sensor are integrated in the valve block; the valve block is connected to the stop valve and the accumulator.

4. The three-axle unmanned transport vehicle steering system according to claim 1, characterized in that: The first filter (341) and the second filter (371) are both provided with a blocking switch; the blocking switch is communicatively connected to the control module (40).

5. The three-axle unmanned transport vehicle steering system according to claim 1, characterized in that: An oil cooler (372) and a temperature sensor (373) are provided on the oil circuit between the oil return end of the steering control circuit and the second filter (371); the oil cooler (372) and the temperature sensor (373) are both communicatively connected to the control module (40).

6. The three-axle unmanned transport vehicle steering system according to claim 1, characterized in that: The oil tank (36) is provided with a liquid level switch (361); the liquid level switch (361) is communicatively connected to the control module (40).

7. The three-axle unmanned transport vehicle steering system according to claim 1, characterized in that: The rotation angle sensors are arranged at both ends of the axle.

8. A three-axle unmanned transport vehicle, characterized in that: A three-axle unmanned transport vehicle steering system as described in any one of claims 1 to 7 is adopted.

9. The three-axle unmanned transport vehicle according to claim 8, characterized in that: The first axle (11) and the second axle (12) are arranged adjacent to each other; the A check valve and / or the A pressure sensor in the steering control circuit of the first axle (11) and the A check valve and / or the A pressure sensor in the steering control circuit of the second axle (12) are integrated in the same valve block.

10. The three-axle unmanned transport vehicle according to claim 9, characterized in that: The second axle (12) and the third axle (13) are arranged adjacent to each other; the A check valve and / or the A pressure sensor in the steering control circuit of the second axle (12) and the A check valve and / or the A pressure sensor in the steering control circuit of the third axle (13) are integrated in the same valve block.

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