Bidirectional driving four-wheel steering automatic control system, control method and vehicle

Abstract

The invention belongs to the technical field of coal mine machinery, and particularly relates to a two-way driving four-wheel steering automatic control system, a control method and a vehicle. The automatic control system comprises a main driving two-way steering oil cylinder and a co-driving two-way steering oil cylinder. A main driving steering gear and a co-driving steering gear; the main driving steering gear is communicated with a main driving two-way steering oil cylinder through an oil way, and the co-driving steering gear is communicated with a co-driving two-way steering oil cylinder through an oil way; a hydraulic oil tank; the main driving two-way steering oil cylinder and the main driving steering gear are in control connection through a steering control valve set, and the co-driving two-way steering oil cylinder and the co-driving steering gear are in control connection through a steering control valve set. The reversing valve and the control proportional valve are integrated into the steering control valve set, on the basis that a control system is simplified as much as possible, automatic return control over the four front and rear tires is achieved through control over the reversing valve and the steering control valve set, and the problem that due to the influence of the external environment, a driver cannot accurately return a vehicle according to the feeling of himself or herself is solved. And the safety risk of vehicle deviation is caused by asynchronous corners of front and rear tires.

Description

Technical Field

[0001] The present invention belongs to the technical field of coal mine machinery, and particularly relates to a two-way driving four-wheel steering automatic control system, a control method and a vehicle. Background Art

[0002] At present, the integral two-way driving vehicle in coal mines is an important auxiliary transportation equipment. The integral two-way driving vehicle has a main cab and a co-driver cab, and has both two-wheel steering and four-wheel steering, which is suitable for transportation in narrow underground roadways. This type of vehicle has the characteristics of a compact body, two-way driving, four-wheel steering, and a small turning radius. When the driver operates the vehicle, the driver can switch the control valve group in the main cab to realize the switching between two-wheel and four-wheel of the vehicle. However, when switching the steering mode, it is necessary to center the front and rear tires before switching. When the front and rear tire angles are inconsistent during driving, the vehicle will deviate, posing a safety hazard.

[0003] When the driver moves from the main cab to the co-driver cab, the two tires on the main driver side change from the front wheels to the "rear wheels". When the two co-driver wheels are steered, the tires on the corresponding side of the co-driver cab cannot be controlled to steer, which violates the driver's steering habit, resulting in poor driving comfort for the driver and prone to misoperation.

[0004] Moreover, the current switching between two-wheel and four-wheel and their respective steering modes are all controlled by manually operating the hydraulic valve. In the underground where the light and visibility are poor, the operation of the vehicle is mainly adjusted and controlled by the driver's feeling. Affected by factors such as the driver's own feeling, underground light, and visibility, the adjustment and control of the tires are inaccurate, resulting in a safety risk of vehicle deviation due to the asynchronous rotation angles of the front and rear tires. Summary of the Invention

[0005] The object of the present invention is to overcome the defects in the prior art that when the two-wheel steering is performed in the main cab and the co-driver cab, the alignment is inaccurate, the tires on the corresponding side of the cab cannot be adjusted and controlled correspondingly for steering, and misoperation is prone to occur. The present invention provides a two-way driving four-wheel steering automatic control system, a control method and a vehicle that can automatically adjust the cab to control the steering of the tires on the corresponding side on the basis of realizing two-wheel steering in the main cab, four-wheel steering in the main cab, two-wheel steering in the co-driver cab, and four-wheel steering in the co-driver cab.

[0006] The technical solution adopted by the present invention to solve its technical problems is as follows:

[0007] As a first aspect, a two-way driving four-wheel steering automatic control system includes:

[0008] A main driver two-way steering oil cylinder and a co-driver two-way steering oil cylinder;

[0009] A main driver steering gear and a co-driver steering gear; the main driver steering gear is in oil circuit communication with the main driver two-way steering oil cylinder, and the co-driver steering gear is in oil circuit communication with the co-driver two-way steering oil cylinder;

[0010] The hydraulic oil tank is connected to both the driver's side steering gear and the co-driver's side steering gear through the oil circuit of the first reversing valve;

[0011] Between the driver's side two-way steering cylinder and the driver's side steering gear, and between the co-driver's side two-way steering cylinder and the co-driver's side steering gear, they are both controlled and connected through a steering control valve group;

[0012] Wherein, the steering control valve group includes: a valve seat; a first reversing valve, a second reversing valve, a third reversing valve and a first proportional control valve installed inside the valve seat;

[0013] The oil port P of the second reversing valve, the working port A of the first proportional control valve, and the working port A of the first reversing valve are connected in an oil circuit; the working oil port B of the first reversing valve, the oil port T of the third reversing valve, and the oil port B of the first proportional control valve are connected in an oil circuit; the oil port T of the second reversing valve is connected to the oil port T of the first reversing valve.

[0014] Further, the working oil port A of the driver's side steering gear, the working oil port A of the co-driver's side steering gear, and the oil inlet port P of the third reversing valve are connected in an oil circuit; the working oil port B of the driver's side steering gear, the working oil port B of the co-driver's side steering gear, and the oil inlet port P of the first reversing valve are connected in an oil circuit;

[0015] The working oil port A of the third reversing valve is connected to the working oil port Z1 of the driver's side two-way steering cylinder, and the working oil port B of the third reversing valve is connected to the working oil port Z2 of the co-driver's side two-way steering cylinder; the working oil port A of the second reversing valve is connected to the working oil port Z3 of the co-driver's side two-way steering cylinder in an oil circuit, and the working oil port B of the second reversing valve is connected to the working oil port Z4 of the driver's side two-way steering cylinder in an oil circuit.

[0016] Further, the first reversing valve, the second reversing valve, and the third reversing valve all adopt explosion-proof electromagnetic two-position four-way reversing valves; the first proportional control valve adopts an explosion-proof proportional three-position four-way reversing valve.

[0017] Further, a filter, a gear pump, and a flow dividing valve are sequentially arranged on the oil circuit between the hydraulic oil tank and the first reversing valve;

[0018] The oil inlet port P of the flow dividing valve is connected to the oil outlet port of the gear pump, the working oil port A of the flow dividing valve is connected to the oil inlet port P of the fourth reversing valve, and the working oil port B of the flow dividing valve is connected to the oil inlet port P of the first proportional control valve.

[0019] Further, the oil port T of the fourth reversing valve, the oil port T of the first proportional control valve, the oil port T of the flow dividing valve, the oil port T of the driver's side steering gear, and the oil port T of the co-driver's side steering gear are all connected to the hydraulic oil tank.

[0020] Further, when the main driver's two-wheel steering state is in effect, the first reversing valve, the second reversing valve, the third reversing valve, the fourth reversing valve, and the first proportional control valve are all de-energized;

[0021] When the main driver's four-wheel steering state is in effect, the second reversing valve, the third reversing valve, the fourth reversing valve, and the first proportional control valve are all de-energized, and the first reversing valve is energized;

[0022] When the co-driver's two-wheel steering state is in effect, the first reversing valve and the first proportional control valve are both de-energized, and the second reversing valve, the third reversing valve, and the fourth reversing valve are all energized;

[0023] When the co-driver's four-wheel steering state is in effect, the first proportional control valve is de-energized, and the first reversing valve, the second reversing valve, the third reversing valve, and the fourth reversing valve are all energized.

[0024] Further, when the main driver's side tire is being controlled to return to the straight position, the steering system is in the co-driver's two-wheel steering state;

[0025] When the co-driver's side tire is being controlled to return to the straight position, the steering system is in the co-driver's two-wheel steering state.

[0026] Further, when the main driver's side tire is deflected to the left and the main driver's side tire is being controlled to return to the straight position:

[0027] The hydraulic oil sequentially flows from the hydraulic oil tank, the filter, the gear pump, the port B of the flow dividing valve, the PA port of the first proportional control valve, the PB port of the second reversing valve, and enters the corresponding oil cavity from the port Z4 of the main driver's side steering cylinder, forming an oil inlet circuit for the main driver's side tire to return to the straight position;

[0028] The hydraulic oil sequentially flows from the port Z1 of the main driver's side steering cylinder, the port A of the third reversing valve, the port T of the third reversing valve, the port B of the first proportional control valve, and the port T of the first proportional control valve, and returns to the hydraulic oil tank, forming an oil return circuit for the main driver's side tire to return to the straight position.

[0029] Further, when the main driver's side tire is deflected to the right and the main driver's side tire is being controlled to return to the straight position:

[0030] Control the internal connection between the port P and the port B of the first proportional control valve, and the hydraulic oil in the hydraulic cylinder enters the corresponding oil cavity from the port Z1 of the main driver's side steering cylinder; control the internal connection between the port A and the port T of the second proportional control valve, and the hydraulic oil in the main driver's side steering cylinder returns to the hydraulic oil tank from the port Z4 of the main driver's side steering cylinder.

[0031] Further, when the co-driver's side tire is deflected to the right and the co-driver's side tire is being controlled to return to the straight position:

[0032] The system is in the state of two-wheel steering on the co-driver side. The right electromagnet of the first proportional valve is energized, controlling the internal connection of the oil ports P and B of the first proportional control valve. The pressure oil passes through the PB oil ports of the first proportional control valve and the TA oil ports of the third hydraulic valve, and enters the oil port Z1 of the steering cylinder on the driver side and into the corresponding oil chamber, forming an oil inlet circuit. The hydraulic oil in the oil chamber corresponding to the oil port Z4 of the steering cylinder on the driver side passes through the BP oil ports of the second reversing valve and the AT oil ports of the first proportional valve, forming an oil return circuit.

[0033] Furthermore, when the co-driver side tire deflects to the left and the co-driver side tire return control is performed:

[0034] The system is in the state of two-wheel steering on the driver side. The left electromagnet of the first proportional valve is energized, controlling the internal connection of the oil ports P and A of the first proportional control valve. The pressure oil passes through the PA oil ports of the first proportional control valve and the PA oil ports of the second hydraulic valve, and enters the oil port Z3 of the steering cylinder on the co-driver side and into the corresponding oil chamber, forming an oil inlet circuit. The hydraulic oil in the oil chamber corresponding to the oil port Z2 of the steering cylinder on the co-driver side passes through the BT oil ports of the third reversing valve and the BT oil ports of the first proportional valve, forming an oil return circuit.

[0035] As a second aspect, a control method for a two-way driving four-wheel steering automatic control system includes the following:

[0036] Step 1: Tire return operation; that is, select a return mode according to the deflection state of the vehicle tire to perform a return operation on the tire. If the tire is in the middle position, this step is not required.

[0037] Step 2: After the tire returns, select the vehicle steering mode; the vehicle operation modes include two-wheel steering mode on the driver side, four-wheel steering mode on the driver side, two-wheel steering mode on the co-driver side, and four-wheel steering mode on the co-driver side.

[0038] Step 3: Control the energization and de-energization of the fourth reversing valve, the first reversing valve, the second reversing valve, the third reversing valve, and the first proportional control valve according to the vehicle steering mode to complete the steering action of the corresponding vehicle steering mode.

[0039] As a third aspect, an integral two-way driving vehicle in a coal mine includes a frame; a driver's cab, a co-driver's cab, a front steering axle, and a rear steering axle installed on the frame; and a two-way driving four-wheel steering automatic control system as described above.

[0040] The driver's side two-way steering cylinder is installed on the front steering axle, and the co-driver's side two-way steering cylinder is installed on the rear steering axle; the main steering gear is installed in the driver's cab, and the auxiliary steering gear is installed in the co-driver's cab.

[0041] Furthermore, a main / co-driver cab control switching knob and a two-wheel / four-wheel steering switching knob are provided in both the main cab and the co-driver cab.

[0042] The beneficial effects of a two-way driving four-wheel steering automatic control system, a control method and a vehicle according to the present invention are as follows:

[0043] In the present invention, two-way steering cylinders are provided on both the front and rear axles. The delivery direction of the oil in the hydraulic oil tank is controlled by a first reversing valve, and then a plurality of reversing valves and a plurality of control proportional valves are integrated into a steering control valve group. On the basis of simplifying the control system as much as possible, through the control of the first reversing valve and the steering control valve group, the automatic return control of the four front and rear tires is realized, replacing the way that the driver needs to observe the return by eyes in the prior art. The control is more accurate and rapid, solving the problems in the prior art that due to the influence of the external environment, the driver cannot accurately return the vehicle by his own feeling, and the safety risk of vehicle deviation caused by the asynchronous rotation angles of the front and rear tires.

[0044] At the same time, when the main and co-driver cabs are switched in the present automatic control system, the "front tires" are also switched together. That is, when the main driver steers two wheels, the two tires on the main driver side are controlled to steer; when the co-driver steers two wheels, the two tires on the co-driver side are controlled to steer, avoiding the misoperation caused by the rear wheels steering and violating the driver's habits. When operating in any cab, the front wheels can be steered, improving the driving safety and comfort.

[0045] Adopting a new electric control logic, a main / co-driver cab control switching knob and a two-wheel / four-wheel steering switching knob are provided in the cab, and the steering mode is controlled by buttons to avoid misoperation. Description of the Drawings

[0046] The present invention will be further described in detail below in conjunction with the drawings and specific embodiments.

[0047] Figure 1 It is a partial structural schematic diagram of an integral two-way driving vehicle underground in a coal mine according to an embodiment of the present invention.

[0048] Figure 2 It is a control diagram of a two-way driving four-wheel steering automatic control system according to an embodiment of the present invention.

[0049] Figure 3 It is a control diagram of a steering control valve group according to an embodiment of the present invention.

[0050] Figure 4 It is a control diagram in the state of two-wheel steering by the main driver according to an embodiment of the present invention.

[0051] Figure 5 It is a control diagram in the state of four-wheel steering by the main driver according to an embodiment of the present invention.

[0052] Figure 6 It is the control diagram when the co-pilot's two wheels are in the steering state in the embodiment of the present invention.

[0053] Figure 7 It is the control diagram when the co-pilot's four wheels are in the steering state in the embodiment of the present invention.

[0054] Figure 8 It is the return control diagram when the main driver's side tire deviates to the left in the embodiment of the present invention.

[0055] Figure 9 It is the return control diagram when the main driver's side tire deviates to the right in the embodiment of the present invention.

[0056] Figure 10 It is the return control diagram when the co-pilot's side tire deviates to the right in the embodiment of the present invention.

[0057] Figure 11 It is the return control diagram when the co-pilot's side tire deviates to the left in the embodiment of the present invention.

[0058] Figure 12 It is the control method of the two-way driving four-wheel steering automatic control system of the present invention.

[0059] In the figure: 11, main driver's two-way steering oil cylinder; 12, co-pilot's two-way steering oil cylinder; 13, main driver's steering gear; 14, co-pilot's steering gear; 15, hydraulic oil tank; 16, fourth reversing valve; 17, steering control valve group, 171, valve seat, 172, first reversing valve, 173, second reversing valve, 174, third reversing valve, 175, first proportional control valve; 18, filter; 19, gear pump; 20, flow dividing valve; 2, main driver's cab; 3, co-pilot's cab; 4, front steering axle; 5, rear steering axle; 6, main and co-pilot's cab control switching knob; 7, two-wheel / four-wheel steering switching knob. Specific embodiments

[0060] Now, the present invention will be further described in detail with reference to the accompanying drawings. These drawings are all simplified schematic diagrams, only illustrating the basic structure of the present invention in a schematic manner, so they only show the components related to the present invention.

[0061] As Figures 1 - 11 shown in a specific embodiment of an integral two-way driving vehicle in a coal mine underground of the present invention, it includes a vehicle frame; a main driver's cab 2, a co-pilot's cab 3, a front steering axle 4, and a rear steering axle 5 installed on the vehicle frame, and a two-way driving four-wheel steering automatic control system is adopted. It should be understood that the installation methods of the front steering axle 4 and the rear steering axle 5 on the vehicle frame, and the installation methods and installation positions of the main driver's cab 2 and the co-pilot's cab 3 on the vehicle frame in the two-way driving vehicle in this embodiment all adopt the prior art, and will not be elaborated in detail here. Those skilled in the art should be able to obtain them simply.

[0062] AsFigure 1 As shown, the integrated two-way driving vehicle in the coal mine underground in this embodiment adopts a new two-way driving four-wheel steering automatic control system and a new electric control logic. A main / auxiliary cab control switching knob 6 and a two-wheel / four-wheel steering switching knob 7 are arranged in the cab, and the steering mode is controlled by buttons to avoid misoperation.

[0063] For further description, participate in Figure 2 , the two-way driving four-wheel steering automatic control system in this embodiment includes: a main driver two-way steering oil cylinder 11, an auxiliary driver two-way steering oil cylinder 12, a main driver steering gear 13, an auxiliary driver steering gear 14, and a hydraulic oil tank 15. The main driver steering gear 13 and the auxiliary driver steering gear 14 are used to control the steering of the corresponding side tires. The main driver steering gear 13 is connected to the main driver two-way steering oil cylinder 11 through an oil circuit, and the auxiliary driver steering gear 14 is connected to the auxiliary driver two-way steering oil cylinder 12 through an oil circuit. The hydraulic oil tank 15 is connected to the main driver steering gear 13 and the auxiliary driver steering gear 14 through a fourth reversing valve 16 by an oil circuit. The connection between the main driver two-way steering oil cylinder 11 and the main driver steering gear 13 and the connection between the auxiliary driver two-way steering oil cylinder 12 and the auxiliary driver steering gear 14 are both controlled by a steering control valve group 17.

[0064] As Figure 3 shown, specifically, the steering control valve group 17 includes: a valve seat 171; a first reversing valve 172, a second reversing valve 173, a third reversing valve 174, and a first proportional control valve 175 installed inside the valve seat 171. The oil port P of the second reversing valve 173, the working port A of the first reversing valve 172, and the working port A of the first proportional control valve 175 are connected by an oil circuit; the working oil port B of the first proportional control valve 175, the oil port T of the third reversing valve 174, and the oil port B of the first reversing valve 172 are connected by an oil circuit; the oil port T of the second reversing valve 173 is connected to the oil port T of the first reversing valve 172. It should be further noted that the main driver two-way steering oil cylinder 11 in this embodiment is installed on the front steering axle 4, the auxiliary driver two-way steering oil cylinder 12 is installed on the rear steering axle 5, the main steering gear is installed in the main cab 2, and the auxiliary steering gear is installed in the auxiliary cab 3.

[0065] In this embodiment, two-way steering oil cylinders are arranged on both the front and rear axles. The fourth reversing valve 16 is used to control the oil delivery direction in the hydraulic oil tank 15, and then a plurality of reversing valves and a plurality of control proportional valves are integrated into the steering control valve group 17. On the basis of simplifying the control system 1 as much as possible, through the control of the fourth reversing valve 16 and the steering control valve group 17, the automatic return control of the four front and rear tires is realized, replacing the way that the driver needs to observe the return by eye in the prior art. The control is more accurate and rapid, and solves the problem of the safety risk of vehicle deviation caused by the different synchronization of the front and rear tire angles due to the influence of the external environment, which makes it impossible for the driver to return the vehicle by his own feeling in the prior art.

[0066] As Figure 3As shown, the working oil port A of the driver's side steering gear 13, the working oil port A of the co-driver's side steering gear 14, and the oil inlet P of the third reversing valve 174 are in oil circuit communication; the working oil port B of the driver's side steering gear 13, the working oil port B of the co-driver's side steering gear 14, and the oil inlet P of the first reversing valve 172 are in oil circuit communication. The working oil port A of the third reversing valve 174 is in communication with the working oil port Z1 of the driver's side two-way steering cylinder 11, and the working oil port B of the third reversing valve 174 is in communication with the working oil port Z2 of the co-driver's side two-way steering cylinder 12; the working oil port A of the second reversing valve 173 is in oil circuit communication with the working oil port Z3 of the co-driver's side two-way steering cylinder 12, and the working oil port B of the second reversing valve 173 is in oil circuit communication with the working oil port Z4 of the driver's side two-way steering cylinder 11.

[0067] To adapt to the use environment of the vehicle underground in the mine, the first reversing valve 172, the second reversing valve 173, the third reversing valve 174, and the fourth reversing valve 16 in this embodiment all adopt two-position four-way explosion-proof reversing valves, and the first proportional control valve 175 adopts a three-position four-way explosion-proof proportional reversing valve.

[0068] In the control system 1 of this embodiment, a filter 18, a gear pump 19, and a flow dividing valve 20 are sequentially arranged on the oil circuit between the hydraulic oil tank 15 and the fourth reversing valve 16. The oil outlet of the hydraulic oil tank 15 is in communication with the oil inlet of the filter 18, the oil outlet of the filter 18 is in communication with the oil inlet of the gear pump 19, and then the oil inlet P of the flow dividing valve 20 is in communication with the oil outlet of the gear pump 19. The working oil port A of the flow dividing valve 20 is in communication with the oil inlet P of the fourth reversing valve 16, and the working oil port B of the flow dividing valve 20 is in communication with the oil inlet P of the first proportional control valve 175.

[0069] In the actual oil circuit, the oil port T of the fourth reversing valve 16, the oil port T of the first proportional control valve 175, the oil port T of the flow dividing valve 20, the oil port T of the driver's side steering gear 13, and the oil port T of the co-driver's side steering gear 14 are all in communication with the hydraulic oil tank 15.

[0070] The driver's side steering gear 13 and the co-driver's side steering gear 14 distribute the pressure oil provided by the gear pump 19 to both side cavities of the driver's side two-way steering cylinder 11 and the co-driver's side two-way steering cylinder 12; the pistons at both ends of the driver's side two-way steering cylinder 11 and the co-driver's side two-way steering cylinder 12 are connected to the knuckles of the tires, and the movement of the piston rods drives the tires to rotate to achieve steering. The two / four-wheel steering switching knobs in the driver's cab 2 and the two / four-wheel steering switching knobs in the co-driver's cab 3 control the switching between the two-wheel steering and four-wheel steering modes of the vehicle. The main / co-driver's cab control switching knob 6 in the driver's cab 2 and the main / co-driver's cab control switching knob 6 in the driver's cab 2 are mainly used for the driver to select which cab to operate in.

[0071] Specifically, as Figure 4As shown in the figure, when the two wheels on the driver's side are in the steering state, the fourth reversing valve 16, the first reversing valve 172, the second reversing valve 173, the third reversing valve 174, and the first proportional control valve 175 are all in the power-off state. The A and B ports of the driver's side steering gear 13 are connected to the P and A ports of the third reversing valve 174, the Z1 and Z4 ports of the driver's side two-way steering cylinder 11, the B and T ports of the second reversing valve 173, and the T and P ports of the first proportional control valve 172 to form a hydraulic circuit. By turning the steering wheel on the driver's side, two-wheel steering on the driver's side can be achieved.

[0072] As Figure 5 As shown in the figure, when the four wheels on the driver's side are in the steering state, the fourth reversing valve 16, the first proportional control valve 175, the second reversing valve 173, the third reversing valve 174, and the first reversing valve 172 are all in the power-off state. The first reversing valve 172 is powered on. The A and B ports of the driver's side steering gear 13 are connected to the P and A ports of the third reversing valve 174, and the Z1 and Z2 ports of the driver's side two-way steering cylinder 11 to form a circuit. The B and T ports of the second reversing valve 173, the T and B ports of the first reversing valve 172, the T and B ports of the third reversing valve 174, the Z2 and Z3 ports of the co-driver's side steering cylinder, the A and P ports of the second reversing valve 173, and the A and P ports of the first reversing valve 172 form a hydraulic circuit. The driver's side two-way steering cylinder 11 and the co-driver's side two-way steering cylinder 12 are connected in series. By turning the steering wheel on the driver's side, four-wheel steering on the driver's side can be achieved.

[0073] As Figure 6 As shown in the figure, when the two wheels on the co-driver's side are in the steering state, the first proportional control valve 175 and the first reversing valve 172 are both in the power-off state, and the fourth reversing valve 16, the third reversing valve 174, and the second reversing valve 173 are all in the powered-on state. The A and B ports of the co-driver's side steering gear 14 are connected to the P and B ports of the third reversing valve 174, the Z2 and Z3 ports of the co-driver's side two-way steering cylinder 12, the A and T ports of the second reversing valve 173, and the T and P ports of the first reversing valve 172 to form a hydraulic circuit. By turning the steering wheel on the co-driver's side, the co-driver's side two-way steering cylinder 12 can move left and right, achieving two-wheel steering on the co-driver's side.

[0074] As Figure 7As shown in the figure, when the co-pilot's four-wheel steering is in operation, the fourth reversing valve 16, the third reversing valve 174, the second reversing valve 173, and the first reversing valve 172 are all energized. The A and B ports of the co-pilot's steering gear 14 are connected to the P and B ports of the third reversing valve 174, the Z2 and Z3 ports of the co-pilot's two-way steering cylinder 12, the A and T ports of the second reversing valve 173, the T and B ports of the first reversing valve 172, the T and A ports of the third reversing valve 174, the Z1 and Z4 ports of the driver's two-way steering cylinder 11, the B and P ports of the second reversing valve 173, and the A and P ports of the first reversing valve 172 to form a hydraulic circuit. By turning the co-pilot's side steering wheel, the co-pilot's two-way steering cylinder 12 can move left and right. The co-pilot's two-way steering cylinder 12 is connected in series with the driver's two-way steering cylinder 11. By turning the co-pilot's side steering wheel, four-wheel steering on the co-pilot's side can be achieved.

[0075] In the two-way driving four-wheel steering automatic control system of this embodiment, when the driver's side tire is being controlled to return to the straight position, the steering system is in the co-pilot's two-wheel steering state. When the co-pilot's side tire is being controlled to return to the straight position, the steering system is in the co-pilot's two-wheel steering state.

[0076] It should be noted that in this embodiment, the driver's side is taken as the front view perspective. When the driver's side tire is deflected to the left and the driver's side tire is being controlled to return to the straight position: the steering system is in the co-pilot's two-wheel steering state, and the electromagnet a of the first proportional control valve 175 is energized. That is, the hydraulic oil sequentially flows from the hydraulic oil tank 15, the filter 18, the gear pump 19, the oil port B of the flow dividing valve 20, the oil port P of the first proportional control valve 175, the oil port A of the first proportional control valve 175, the oil port P of the second reversing valve 173, and the oil port B of the second reversing valve 173, and enters the corresponding oil cavity from the oil port Z4 of the driver's side steering cylinder, forming an oil inlet circuit for the driver's side tire to return to the straight position. The hydraulic oil sequentially flows from the oil port Z1 of the driver's side steering cylinder, the oil port A of the third reversing valve 174, the oil port T of the third reversing valve 174, the oil port B of the first proportional control valve 175, and the oil port T of the second proportional control valve 175, and returns to the hydraulic oil tank 15, forming an oil return circuit for the driver's side tire to return to the straight position. For details, see Figure 8 。

[0077] The hydraulic oil enters from the oil port Z4 of the driver's side steering cylinder. The piston of the driver's side two-way steering cylinder moves to the left, and the piston rod pulls the driver's side tire to rotate clockwise until the tire is parallel to the vehicle body and stops rotating, realizing the action of the driver's side tire returning to the straight position.

[0078] When the driver's side tire is deflected to the right and the driver's side tire is being controlled to return to the straight position: the electromagnet b of the first proportional control valve is energized, that is, the oil port P and the oil port B inside the first proportional control valve 175 are connected.

[0079] Specifically, as shown in Figure 9As shown, the steering system is in the state of two-wheel steering on the co-driver side. The electromagnet b of the first proportional control valve 175 is energized. The hydraulic oil sequentially flows from the hydraulic oil tank 15, the filter 18, the gear pump 19, the port B of the flow dividing valve 20, the port P of the first proportional control valve 175, the port B of the first proportional control valve 172, the port T of the third reversing valve 174, and the port A of the third reversing valve 174, and enters the corresponding oil cavity from the port Z1 of the steering cylinder on the driver side, forming an oil inlet circuit for the driver-side tire to return to the straight position. The hydraulic oil sequentially flows from the port Z4 of the driver-side steering cylinder, the port B of the second reversing valve 173, the port P of the second reversing valve 173, the port A of the first proportional control valve 175, and the port T of the second proportional control valve 175, and returns to the hydraulic oil tank 15, forming an oil return circuit for the driver-side tire to return to the straight position.

[0080] The hydraulic oil enters from the Z1 port of the driver's two-way steering cylinder 11. The piston rod of the driver's two-way steering cylinder 11 pulls the driver-side tire to rotate counterclockwise until the tire stops rotating when it is parallel to the vehicle body, realizing the action of the tire returning to the straight position.

[0081] When the co-driver side tire is deflected to the left, and this embodiment takes the driver side as the front view perspective for controlling the co-driver side tire to return to the straight position: As Figure 10 shown, the steering system is in the state of two-wheel steering on the driver side. Control the electromagnet b of the second proportional control valve 175 to be energized, that is, the inside of the port P and the port B of the first proportional control valve 175 are connected. Specifically, as Figure 8 shown, the hydraulic oil sequentially flows from the hydraulic oil tank 15, the filter 18, the gear pump 19, the port P of the flow dividing valve 20, the port B of the flow dividing valve 20, the port P of the first proportional control valve 175, the port B of the first proportional control valve 175, the port T of the third reversing valve 173, and the port B of the third reversing valve 173, and enters the corresponding oil cavity from the port Z2 of the co-driver side steering cylinder, forming an oil inlet circuit for the co-driver side tire to return to the straight position. The hydraulic oil sequentially flows from the port Z3 of the co-driver side steering cylinder, the port A of the third reversing valve 174, the port P of the third reversing valve 174, the port A of the first proportional control valve 175, and the port T of the second proportional control valve 175, and returns to the hydraulic oil tank 15, forming an oil return circuit for the co-driver side tire to return to the straight position.

[0082] The hydraulic oil enters from the Z2 port of the co-driver's two-way steering cylinder 12. The piston of the co-driver's two-way steering cylinder 12 moves to the right, and the piston rod pulls the co-driver side tire to rotate clockwise until the tire stops rotating when it is parallel to the vehicle body, realizing the return of the co-driver side tire to the straight position.

[0083] When the co-driver side tire is deflected to the right and the co-driver side tire is controlled to return to the straight position: The steering system is in the state of two-wheel steering on the driver side. Control the electromagnet a of the first proportional control valve 175 to be energized, that is, control the inside of the port P and the port A of the first proportional control valve 175 to be connected. Specifically, as Figure 11As shown in the figure, when the a electromagnet of the second proportional control valve 175 is energized, the hydraulic oil sequentially flows from the hydraulic oil tank 15, the filter 18, the gear pump 19, the oil port P of the flow dividing valve 20, the oil port B of the flow dividing valve 20, the oil port P of the first proportional control valve 175, the oil port A of the first proportional control valve 175, the oil port P of the second reversing valve 173, and the oil port A of the second reversing valve 173, and enters the corresponding oil cavity from the oil port Z3 of the co-driver side steering cylinder, forming an oil inlet circuit for the co-driver side tire to return to the straight position. The hydraulic oil sequentially flows from the oil port Z2 of the co-driver side steering cylinder, the oil port B of the third reversing valve 174, the oil port T of the third reversing valve 174, the oil port B of the first proportional control valve 175, and the oil port T of the first proportional control valve 175, and returns to the hydraulic oil tank 15, forming an oil return circuit for the co-driver side tire to return to the straight position. The pressure oil reaches the Z3 port of the co-driver two-way steering cylinder 12, pulling the co-driver side tire to rotate counterclockwise to achieve the tire return-to-straight operation.

[0084] To sum up, when the main and co-driver cabs are switched in this automatic control system, the "front tires" are also switched together. That is, when the two main driver wheels are steering, the two tires on the main driver side are controlled to steer; when the two co-driver wheels are steering, the two tires on the co-driver side are controlled to steer, avoiding misoperations caused by rear wheel steering and going against the driver's habits. When operating in either cab, front wheel steering can be achieved, improving driving safety and comfort.

[0085] As Figure 12 shown, based on the control method of the above two-way driving four-wheel steering automatic control system, it includes the following contents:

[0086] Step 1: Tire return-to-straight operation; that is, select the return-to-straight mode according to the deflection state of the vehicle tires to perform the tire return-to-straight operation.

[0087] Step 2: After the tires return to the straight position, select the vehicle steering mode; the vehicle operation modes include the two-wheel steering mode of the main driver, the four-wheel steering mode of the main driver, the two-wheel steering mode of the co-driver, and the four-wheel steering mode of the co-driver.

[0088] Step 3: According to the vehicle steering mode, control the energization and de-energization of the first reversing valve, the second reversing valve, the third reversing valve, the fourth reversing valve, and the first proportional control valve to complete the steering action of the corresponding vehicle steering mode.

[0089] In controlling the steering of a vehicle, first, the deflection state of the wheels is judged by relevant personnel, and the corresponding four-wheel steering states of the driver's and co-driver's sides are switched. According to the tire deflection state, the driver turns the corresponding steering wheel to adjust the tires. Then, according to the selected vehicle steering mode, the fourth reversing valve 16, the first reversing valve 172, the second reversing valve 173, the third reversing valve 174, and the first proportional control valve 175 are energized or de-energized. By using a relatively simple valve group, the functions of adjusting the tires on the same side of the cab, two-wheel steering of the driver's side, four-wheel steering of the driver's side, two-wheel steering of the co-driver's side, and four-wheel steering of the co-driver's side can be achieved. The adjustment is accurate and fast, avoiding the safety risk of vehicle deviation caused by the asynchronous rotation angles of the front and rear tires. The function coverage is large and it is easy to control.

[0090] It should be understood that the specific embodiments described above are only used to explain the present invention and are not used to limit the present invention. Obvious changes or variations derived from the spirit of the present invention are still within the protection scope of the present invention.

Claims

1. A two-way driving four-wheel steering automatic control system, characterized in that: include: Driver's two-way steering cylinder and co-driver's two-way steering cylinder; A main driver's steering gear and a co-driver's steering gear, wherein the main driver's steering gear is connected to the main driver's two-way steering cylinder oil circuit, and the co-driver's steering gear is connected to the co-driver's two-way steering cylinder oil circuit; A hydraulic oil tank, connected to the main driver's steering gear and the assistant driver's steering gear through a first reversing valve oil circuit; The main driver's two-way steering oil cylinder and the main driver's steering gear, and the co-driver's two-way steering oil cylinder and the co-driver's steering gear are both controlled and connected via a steering control valve group; Wherein, the steering control valve group includes: a valve seat; a first reversing valve, a second reversing valve, a third reversing valve and a first proportional control valve installed inside the valve seat; The oil port P of the second reversing valve, the working port A of the first proportional control valve, and the working port A of the first reversing valve are oil-circuit connected; the working oil port B of the first reversing valve, the oil port T of the third reversing valve, and the oil port B of the first proportional control valve are oil-circuit connected; the oil port T of the second reversing valve is oil-circuit connected with the oil port T of the first reversing valve.

2. A two-way driving four-wheel steering automatic control system according to claim 1, characterized in that: The working oil port A of the main driving steering gear, the working oil port A of the auxiliary driving steering gear, and the oil inlet P of the third reversing valve are in oil communication; the working oil port B of the main driving steering gear, the working oil port B of the auxiliary driving steering gear, and the oil inlet P of the first reversing valve are in oil communication; The working oil port A of the third reversing valve is connected to the working oil port Z1 of the main driver's two-way steering cylinder, and the working oil port B of the third reversing valve is connected to the working oil port Z2 of the passenger's two-way steering cylinder; the working oil port A of the second reversing valve is connected to the working oil port Z3 of the passenger's two-way steering cylinder, and the working oil port B of the second reversing valve is connected to the working oil port Z4 of the main driver's two-way steering cylinder.

3. A two-way driving four-wheel steering automatic control system according to claim 1, characterized in that: The first reversing valve, the second reversing valve and the third reversing valve are all explosion-proof electromagnetic two-position four-way reversing valves; the first proportional control valve is an explosion-proof proportional three-position four-way reversing valve.

4. A two-way driving four-wheel steering automatic control system according to claim 1, characterized in that: A filter, a gear pump and a diverter valve are sequentially arranged on the oil circuit between the hydraulic oil tank and the fourth reversing valve; The oil inlet P of the diverter valve is connected to the oil outlet of the gear pump, the working oil port A of the diverter valve is connected to the oil inlet P of the fourth reversing valve, and the working oil port B of the diverter valve is connected to the oil inlet P of the first proportional control valve.

5. A two-way driving four-wheel steering automatic control system according to claim 4, characterized in that: The oil port T of the fourth reversing valve, the oil port T of the first proportional control valve, the oil port T of the diverter valve, the oil port T of the driver's steering gear, and the oil port T of the passenger's steering gear are all connected to the hydraulic oil tank.

6. A two-way driving four-wheel steering automatic control system according to claim 4, characterized in that: When the main driving two-wheel steering state, the first reversing valve, the second reversing valve, the third reversing valve, the fourth reversing valve and the first proportional control valve are all in a power-off state; When the driver is in the four-wheel steering state, the second reversing valve, the third reversing valve, the fourth reversing valve and the first proportional control valve are all in the power-off state, and the first reversing valve is powered; When the co-pilot two-wheel steering state, the first reversing valve and the first proportional control valve are both in a power-off state, and the second reversing valve, the third reversing valve, and the fourth reversing valve are all in a power-on state; When the passenger car is in four-wheel steering state, the first proportional control valve is in a power-off state, and the first reversing valve, the second reversing valve, the third reversing valve, and the fourth reversing valve are all in a power-on state.

7. A two-way driving four-wheel steering automatic control system according to claim 6, characterized in that: When the driver's side tire is in the centering control mode, the steering system is in the passenger side two-wheel steering state; When the passenger side tire is returning to the center, the steering system is in the driver side two-wheel steering state.

8. A two-way driving four-wheel steering automatic control system according to claim 7, characterized in that: When the driver's side tire deviates to the left and the driver's side tire return control is performed: The electromagnet a of the first proportional control valve is energized, and the hydraulic oil sequentially flows from the hydraulic oil tank, the filter, the gear pump, the oil port B of the diverter valve, the oil port P and the oil port A of the first proportional control valve, the oil port P and the oil port B of the second reversing valve, and the oil port Z4 of the steering cylinder on the driver's side into the oil chamber, forming an oil inlet path for returning the tire on the driver's side to the center position; The hydraulic oil returns to the hydraulic oil tank from the oil port Z1 of the main driver's side steering cylinder, the oil port A and oil port T of the third reversing valve, the oil port B and oil port T of the first proportional control valve in turn, forming an oil return path for the main driver's side tire to return to the center position.

9. The two-way driving four-wheel steering automatic control system according to claim 7, characterized in that: When the driver's side tire deviates to the right and the driver's side tire return control is performed: The electromagnet b of the first proportional control valve is energized to control the internal communication between the oil port P and the oil port B of the first proportional control valve. The pressure oil passes through the oil port P and the oil port B of the first proportional control valve, the oil port T and the oil port A of the third hydraulic valve, and enters the corresponding oil chamber from the oil port Z1 of the steering cylinder on the main driving side, forming an oil inlet circuit. The hydraulic oil in the oil chamber corresponding to the oil port Z4 of the driver's side steering cylinder passes through the oil port B and the oil port P of the second reversing valve, and the oil port A and the oil port T of the first proportional control valve to form an oil return circuit.

10. The two-way driving four-wheel steering automatic control system according to claim 7, characterized in that: When the passenger side tire deviates to the right and the passenger side tire return control is performed: When the steering system is in the driver's side two-wheel steering state, the electromagnet b of the first proportional control valve is energized, controlling the internal connection between the oil port P and the oil port B of the first proportional control valve, and the pressure oil passes through the oil port P and the oil port B of the first proportional control valve, the oil port T and the oil port B of the third hydraulic valve, and enters the corresponding oil chamber from the oil port Z2 of the co-driver's side steering cylinder, forming an oil inlet circuit; The hydraulic oil in the oil chamber corresponding to the oil port Z3 of the passenger side steering cylinder passes through the oil port A and the oil port P of the second reversing valve, and the oil port A and the oil port T of the first proportional control valve to form an oil return circuit.

11. The two-way driving four-wheel steering automatic control system according to claim 7, characterized in that: When the passenger side tire deviates to the left and the passenger side tire return control is performed: The electromagnet a of the first proportional control valve is energized to control the internal communication between the oil port P and the oil port A of the first proportional control valve, and the pressure oil passes through the oil port P and the oil port A of the first proportional control valve, the oil port P and the oil port A of the second hydraulic valve, and enters the corresponding oil chamber from the oil port Z3 of the steering cylinder on the passenger side, forming an oil inlet circuit; The hydraulic oil in the oil chamber corresponding to the oil port Z2 of the passenger side steering cylinder passes through the oil port B and the oil port T of the third reversing valve and the oil port B and the oil port T of the first proportional control valve to form an oil return circuit.

12. A control method for a two-way driving four-wheel steering automatic control system according to any one of claims 7 to 11, characterized in that: Includes the following: Step 1: Tire alignment operation; that is, selecting an alignment mode according to the deflection state of the vehicle tire to perform a tire alignment operation; Step 2: After the tire is straightened, select a vehicle steering mode; the vehicle operation mode includes a main driver two-wheel steering mode, a main driver four-wheel steering mode, a co-driver two-wheel steering mode, and a co-driver four-wheel steering mode; Step 3: Control the power gain and loss of the first reversing valve, the second reversing valve, the third reversing valve, the fourth reversing valve, and the first proportional control valve according to the vehicle steering mode to complete the steering action corresponding to the vehicle steering mode.

13. An integrated two-way driving vehicle for underground coal mines, comprising a frame; a main driving cab, a co-driving cab, a front steering axle, and a rear steering axle mounted on the frame; characterized in that: A two-way driving four-wheel steering automatic control system as claimed in any one of claims 1 to 11 is adopted; The main driver's two-way steering cylinder is installed on the front steering axle, and the assistant driver's two-way steering cylinder is installed on the rear steering axle; the main steering gear is installed on the main driving cab, and the assistant steering gear is installed on the assistant driving cab.

14. The integrated two-way driving vehicle for underground coal mines according to claim 13, characterized in that: The main and co-driver cabs are both provided with a main and co-driver cab control switch knob and a two-wheel / four-wheel steering switch knob.

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