Hydraulic walking control system, control method and aerial work vehicle

Abstract

The invention discloses a hydraulic walking control system and method and a high-altitude operation vehicle. The system comprises a walking pump, a first flow distributing and collecting valve, a second flow distributing and collecting valve and all walking motors. A port A of the walking pump is connected with a third port of the first flow distributing and collecting valve and a third port of the second flow distributing and collecting valve, and a port B of the walking pump is connected with a port B of the left front walking motor, a port B of the left rear walking motor, a port A of the right front walking motor and a port A of the right rear walking motor. A fourth port of the first flow distributing and collecting valve is connected with a port A of a left front walking motor, and a second port of the first flow distributing and collecting valve is connected with a port A of a left rear walking motor; a fourth port of the second flow distributing and collecting valve is connected with a port B of the right front walking motor, and a second port of the second flow distributing and collecting valve is connected with a port B of the right rear walking motor. The problem that the walking effect is affected due to the fact that flow and pressure change is caused by slipping during walking is solved.

Description

Technical Field

[0001] The present invention belongs to the technical field of hydraulic control, and in particular relates to a hydraulic travel control system, a control method and an aerial work vehicle. Background Art

[0002] The travel control system used by existing aerial work vehicles usually includes a diverter and collector valve, a front axle, a rear axle and a travel motor. The oil is diverted to the front and rear axles through three diverter and collector valves, and then to the four travel motors. The specific control methods include: diverting to the two travel motors of the front wheels and the two travel motors of the rear wheels through the diverter and collector valve, or diverting to the right front motor and the left rear motor and the left motor and the right rear motor through the diverter and collector valve. Throttling damping is used to control the oil channel connection at both ends of each diverter and collector valve, which plays a role in regulating the different flow requirements of each travel motor caused by uneven ground conditions, ensuring that the travel speed of each travel motor can be consistent when different situations occur, and there will be no tire dragging. The system is also equipped with an overflow valve, a flushing valve and different reversing throttle valves to achieve climbing and flat ground travel.

[0003] The disadvantages of the above two hydraulic travel control methods are: when climbing a slope, if the front wheel slips, the load pressure of the front wheel travel motor will be seriously reduced. When the pressure difference between the front wheel travel motor and the rear wheel travel motor is large, the oil will pass through the throttling damping to the low-pressure side, causing the front wheel to spin, greatly reducing the climbing effect, showing that the climbing is weak and even unable to climb in severe cases; when traveling on flat ground, due to the influence of the throttling damping and the reversing throttle valve, the pressure will be high and the speed will drop when traveling and turning, and it will also be affected by the throttling damping and the reversing throttle valve when retreating.

[0004] At the same time, due to a large number of throttling damping, reversing throttle valves and overflow valves, the system pressure loss is increased, thereby increasing energy consumption loss and increasing the cost of use. In addition, the costs of these two hydraulic travel control solutions are relatively high. Summary of the invention

[0005] The purpose of the present invention is to provide a hydraulic travel control system, a control method and an aerial work vehicle to solve at least one of the problems that the traditional control method easily causes the front wheels to spin when climbing, affecting the climbing effect, and the large number of valve cores increases energy loss and increases system cost.

[0006] The present invention solves the above-mentioned technical problems through the following technical solutions: a hydraulic travel control system, comprising a travel pump, a first diverter and collector valve, a second diverter and collector valve, a left front travel motor, a left rear travel motor, a right front travel motor and a right rear travel motor; the A port of the travel pump is connected to the third port of the first diverter and collector valve and the third port of the second diverter and collector valve, and the B port of the travel pump is connected to the B port of the left front travel motor, the B port of the left rear travel motor, the A port of the right front travel motor and the A port of the right rear travel motor; the fourth port of the first diverter and collector valve is connected to the A port of the left front travel motor, and the second port of the first diverter and collector valve is connected to the A port of the left rear travel motor; the fourth port of the second diverter and collector valve is connected to the B port of the right front travel motor, and the second port of the second diverter and collector valve is connected to the B port of the right rear travel motor.

[0007] Furthermore, the system also includes a shuttle valve and a flushing valve, the two ends of the shuttle valve are respectively connected to the A port and the B port of the travel pump; the first port and the second port of the flushing valve are respectively connected to the A port and the B port of the travel pump, and the third port of the flushing valve is connected to the hydraulic oil tank through the oil return port.

[0008] Furthermore, a first throttling element is provided on the pipeline between the third port of the flushing valve and the oil return port.

[0009] Furthermore, the second port of the first flow diverter and collector valve is also connected to the fourth port of the first flow diverter and collector valve through a second throttling member; the second port of the second flow diverter and collector valve is also connected to the fourth port of the second flow diverter and collector valve through a third throttling member.

[0010] Further, the second port of the first flow dividing and collecting valve is also connected to the fourth port of the first flow dividing and collecting valve through the first one-way valve and the second one-way valve; the second port of the second flow dividing and collecting valve is also connected to the fourth port of the second flow dividing and collecting valve through the third one-way valve and the fourth one-way valve;

[0011] The connection point between the first one-way valve and the second one-way valve, and the connection point between the third one-way valve and the fourth one-way valve are both connected to the oil replenishment pump integrated in the travel pump through the oil replenishment port.

[0012] Furthermore, the system also includes a first pressure sensor and a second pressure sensor, wherein the first pressure sensor is used to detect the pressure of port A of the travel pump, and the second pressure sensor is used to detect the pressure of port B of the travel pump.

[0013] Based on the same concept, the present invention provides an aerial work vehicle, the vehicle comprising the hydraulic travel control system as described above.

[0014] Based on the same concept, the present invention provides a hydraulic travel control method, which is applied to the hydraulic travel control system as described above, and the control method includes:

[0015] When moving forward, the oil flows from the A port of the travel pump into the third port of the first flow-dividing and collecting valve and the third port of the second flow-dividing and collecting valve; then the oil is divided in equal proportion to the A port of the left rear travel motor and the A port of the left front travel motor through the second port and the fourth port of the first flow-dividing and collecting valve, and the oil is divided in equal proportion to the B port of the right rear travel motor and the B port of the right front travel motor through the second port and the fourth port of the second flow-dividing and collecting valve; the oil flows back to the B port of the travel pump after passing through the left rear travel motor, the left front travel motor, the right rear travel motor and the right front travel motor;

[0016] When moving backward, the oil flows directly from the B port of the travel pump into the B port of the left rear travel motor, the B port of the left front travel motor, the A port of the right rear travel motor and the A port of the right front travel motor; the oil flows into the second port of the first diverter-collecting valve after passing through the left rear travel motor, the oil flows into the fourth port of the first diverter-collecting valve after passing through the left front travel motor, the oil flows into the second port of the second diverter-collecting valve after passing through the right rear travel motor, and the oil flows into the fourth port of the second diverter-collecting valve after passing through the right front travel motor; finally, the oil flows back to the A port of the travel pump through the first diverter-collecting valve and the second diverter-collecting valve.

[0017] Beneficial Effects

[0018] Compared with the prior art, the advantages of the present invention are:

[0019] The present invention performs shunt control on the left travel motor (including the left front travel motor and the left rear travel motor) through the first shunt and collector valve, and performs shunt control on the right travel motor (including the right front travel motor and the right rear travel motor) through the second shunt and collector valve, that is, the present invention adopts the same-side shunt control method; when walking (including climbing), since the same-side shunt control is adopted, even if one tire slips, it will not affect the flow and pressure of the tire on the other side, and therefore will not affect the climbing effect, thus avoiding the problem that the flow and pressure changes due to slipping during walking, thereby affecting the walking (including climbing) effect.

[0020] The present invention only uses the first diverter-collector valve and the second diverter-collector valve when moving backward, which greatly reduces the cost of use; it eliminates excessive damping and valve groups, greatly reduces pressure loss, reduces the cost of system components, and avoids the problems of pressure buildup and speed loss caused by inconsistent flow due to turning when traveling at high and low speeds on flat ground. BRIEF DESCRIPTION OF THE DRAWINGS

[0021] In order to more clearly illustrate the technical solution of the present invention, the drawings required for use in the description of the embodiments will be briefly introduced below. Obviously, the drawings described below are only one embodiment of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative work.

[0022] Figure 1 is a schematic diagram of a hydraulic travel control system in an embodiment of the present invention;

[0023] Figure 2 is an oil flow diagram of the hydraulic travel control system when moving forward in an embodiment of the present invention;

[0024] Figure 3 1 is an oil flow diagram of the hydraulic travel control system when moving backward in an embodiment of the present invention.

[0025] Explanation of the reference numerals in the accompanying drawings: 1-first pressure sensor, 2-shuttle valve, 3-flush valve, 4-second pressure sensor, 5-left front travel motor, 6-right front travel motor, 7-second diverter and collector valve, 8-third one-way valve, 9-fourth one-way valve, 10-right rear travel motor, 11-first one-way valve, 12-left rear travel motor, 13-first diverter and collector valve, 14-second one-way valve, MA-measuring point of the first pressure sensor, MB-measuring point of the second pressure sensor, T-oil return port, M-reserved port, T1-oil replenishment port, LFB-port B of the left front travel motor, LFA-port A of the left front travel motor, LRB-port B of the left rear travel motor, LRA-port A of the left rear travel motor, RFA-port A of the right front travel motor, RFB-port B of the right front travel motor, RRA-port A of the right rear travel motor, RRB-port B of the right rear travel motor. DETAILED DESCRIPTION

[0026] The following is a clear and complete description of the technical solutions in the present invention in conjunction with the drawings in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0027] The technical solution of the present application is described in detail with specific embodiments below. The following specific embodiments can be combined with each other, and the same or similar concepts or processes may not be described in detail in some embodiments.

[0028] like Figure 1As shown, a hydraulic travel control system provided by an embodiment of the present invention includes a travel pump, a first diverter and collector valve 13, a second diverter and collector valve 7, a left front travel motor 5, a left rear travel motor 12, a right front travel motor 6 and a right rear travel motor 10; the A port of the travel pump is connected to the third port of the first diverter and collector valve 13 and the third port of the second diverter and collector valve 7, and the B port of the travel pump is connected to the B port of the left front travel motor 5, the B port of the left rear travel motor 12, the A port of the right front travel motor 6 and the A port of the right rear travel motor 10; the fourth port of the first diverter and collector valve 13 is connected to the A port of the left front travel motor 5, and the second port of the first diverter and collector valve 13 is connected to the A port of the left rear travel motor 12; the fourth port of the second diverter and collector valve 7 is connected to the B port of the right front travel motor 6, and the second port of the second diverter and collector valve 7 is connected to the B port of the right rear travel motor 10.

[0029] like Figure 2 As shown, when moving forward, the oil flows from the A port of the travel pump into the third port of the first diverter and collector valve 13 and the third port of the second diverter and collector valve 7; then the oil is diverted in equal proportion to the A port of the left rear travel motor 12 and the A port of the left front travel motor 5 through the second port and the fourth port of the first diverter and collector valve 13, and the oil is diverted in equal proportion to the B port of the right rear travel motor 10 and the B port of the right front travel motor 6 through the second port and the fourth port of the second diverter and collector valve 7; after passing through the left rear travel motor 12, the left front travel motor 5, the right rear travel motor 10 and the right front travel motor 6, the oil flows back to the B port of the travel pump.

[0030] like Figure 3 As shown, when moving backward, the oil flows directly from the B port of the travel pump into the B port of the left rear travel motor 12, the B port of the left front travel motor 5, the A port of the right rear travel motor 10 and the A port of the right front travel motor 6; the oil flows into the second port of the first diverter and collector valve 13 after passing through the left rear travel motor 12, the oil flows into the fourth port of the first diverter and collector valve 13 after passing through the left front travel motor 5, the oil flows into the second port of the second diverter and collector valve 7 after passing through the right rear travel motor 10, and the oil flows into the fourth port of the second diverter and collector valve 7 after passing through the right front travel motor 6; finally, the oil flows back to the A port of the travel pump through the first diverter and collector valve 13 and the second diverter and collector valve 7.

[0031] The present invention adopts a same-side shunt control method, that is, the left travel motor (including the left front travel motor 5 and the left rear travel motor 12) is shunted and controlled by the first shunt and collector valve 13, and the right travel motor (including the right front travel motor 6 and the right rear travel motor 10) is shunted and controlled by the second shunt and collector valve 7; when walking (including climbing), even if one tire slips, it will not affect the flow and pressure of the tire on the other side, so it will not affect the walking and climbing effects. When retreating, the oil flows directly from the travel pump to the travel motor through the travel control valve without passing through other damping and valve groups, etc., which greatly reduces the cost of use. The present invention eliminates valve groups such as overflow valves, reversing valves, and throttle valves, greatly reducing losses, improving efficiency, and reducing system costs. The present invention uses fewer valve groups, and will not cause pressure build-up and speed loss when the vehicle turns, and the overall pressure is relatively low.

[0032] The present invention abandons the traditional control method and uses three diverter and collector valves to make the oil form a diagonal diverter or front and rear wheel diverter, changes the control method of the hydraulic walking system, that is, uses two diverter and collector valves to perform same-side diverter control, avoiding the problem of changes in flow and pressure due to slipping during walking, which in turn affects the walking (including climbing) effect.

[0033] In a specific embodiment of the present invention, the travel control system also includes a shuttle valve 2 and a flushing valve 3, the two ends of the shuttle valve 2 are respectively connected to the A port and the B port of the travel pump; the first port and the second port of the flushing valve 3 are respectively connected to the A port and the B port of the travel pump, and the third port of the flushing valve 3 is connected to the hydraulic oil tank through the return oil port T.

[0034] In a specific embodiment of the present invention, a first throttle is further provided on the pipeline between the third port of the flushing valve 3 and the oil return port T. In this embodiment, the first throttle uses a damper with a diameter of 2.0, through which the flushing flow of the walking action oil is adjusted.

[0035] In a specific embodiment of the present invention, the second port of the first diverter and collector valve 13 is also connected to the fourth port of the first diverter and collector valve 13 through a second throttle member; the second port of the second diverter and collector valve 7 is also connected to the fourth port of the second diverter and collector valve 7 through a third throttle member.

[0036] In this embodiment, the second throttle and the third throttle are both two dampers, and the diameters of the two dampers are 0.6 and 2.5 respectively. The dampers are used to control the connection of the oil passage. When the ground inequality causes the required flow of each travel motor to be different, the damper with a diameter of 0.6 is used for adjustment to ensure that when the required flow of each travel motor is different, the travel speed of each travel motor can be made consistent, and the tire dragging phenomenon will not occur.

[0037] In a specific embodiment of the present invention, the second port of the first diverter and collector valve 13 is also connected to the fourth port of the first diverter and collector valve 13 through the first one-way valve 11 and the second one-way valve 14; the second port of the second diverter and collector valve 7 is also connected to the fourth port of the second diverter and collector valve 7 through the third one-way valve 8 and the fourth one-way valve 9; the connection point between the first one-way valve 11 and the second one-way valve 14, and the connection point between the third one-way valve 8 and the fourth one-way valve 9 are both connected to the oil replenishment pump integrated in the travel pump through the oil replenishment port T1.

[0038] When the road surface is uneven or the flow demand is large, the oil in the oil replenishing pump replenishes oil to the left rear travel motor A port and the left front travel motor A port respectively through the first one-way valve 11 and the second one-way valve 14; the oil in the oil replenishing pump replenishes oil to the right rear travel motor B port and the right front travel motor B port respectively through the third one-way valve 8 and the fourth one-way valve 9.

[0039] In a specific embodiment of the present invention, the walking control system further includes a first pressure sensor 1 and a second pressure sensor 4. The first pressure sensor 1 is used to detect the pressure at port A of the walking pump, and the second pressure sensor 4 is used to detect the pressure at port B of the walking pump.

[0040] The working state of the system is judged according to the pressure values ​​detected by the first pressure sensor 1 and the second pressure sensor 4, and the fault conditions during use are timely known.

[0041] The travel control system of the present invention is compared with the travel control scheme currently used in existing models. It can be seen that the pressure, return oil back pressure and pressure loss of the travel control system of the present invention are all small, and there is no pressure holding and speed drop phenomenon in high and low speed and steering travel, and the climbing effect is good.

[0042] A hydraulic travel control method provided in an embodiment of the present invention is applied to a hydraulic travel control system in an embodiment of the present application. The control method includes:

[0043] like Figure 2 As shown, when moving forward, the oil flows from the A port of the travel pump into the third port of the first diverter and collector valve 13 and the third port of the second diverter and collector valve 7; then the oil is diverted in equal proportion to the A port of the left rear travel motor 12 and the A port of the left front travel motor 5 through the second port and the fourth port of the first diverter and collector valve 13, and the oil is diverted in equal proportion to the B port of the right rear travel motor 10 and the B port of the right front travel motor 6 through the second port and the fourth port of the second diverter and collector valve 7; after passing through the left rear travel motor 12, the left front travel motor 5, the right rear travel motor 10 and the right front travel motor 6, the oil flows back to the B port of the travel pump.

[0044] like Figure 3As shown, when moving backward, the oil flows directly from the B port of the travel pump into the B port of the left rear travel motor 12, the B port of the left front travel motor 5, the A port of the right rear travel motor 10 and the A port of the right front travel motor 6; the oil flows into the second port of the first diverter and collector valve 13 after passing through the left rear travel motor 12, the oil flows into the fourth port of the first diverter and collector valve 13 after passing through the left front travel motor 5, the oil flows into the second port of the second diverter and collector valve 7 after passing through the right rear travel motor 10, and the oil flows into the fourth port of the second diverter and collector valve 7 after passing through the right front travel motor 6; finally, the oil flows back to the A port of the travel pump through the first diverter and collector valve 13 and the second diverter and collector valve 7.

[0045] What is disclosed above is only a specific implementation mode of the present invention, but the protection scope of the present invention is not limited thereto. Any technician familiar with the technical field can easily think of changes or modifications within the technical scope disclosed in the present invention, which should be covered within the protection scope of the present invention.

Claims

1. A hydraulic travel control system, characterized in that: The system includes a travel pump, a first diverter and collector valve, a second diverter and collector valve, a left front travel motor, a left rear travel motor, a right front travel motor and a right rear travel motor; the A port of the travel pump is connected to the third port of the first diverter and collector valve and the third port of the second diverter and collector valve, and the B port of the travel pump is connected to the B port of the left front travel motor, the B port of the left rear travel motor, the A port of the right front travel motor and the A port of the right rear travel motor; the fourth port of the first diverter and collector valve is connected to the A port of the left front travel motor, and the second port of the first diverter and collector valve is connected to the A port of the left rear travel motor; the fourth port of the second diverter and collector valve is connected to the B port of the right front travel motor, and the second port of the second diverter and collector valve is connected to the B port of the right rear travel motor.

2. The hydraulic travel control system according to claim 1, characterized in that: The system also includes a shuttle valve and a flushing valve, wherein the two ends of the shuttle valve are respectively connected to the A port and the B port of the travel pump; the first port and the second port of the flushing valve are respectively connected to the A port and the B port of the travel pump, and the third port of the flushing valve is connected to the hydraulic oil tank through the oil return port.

3. The hydraulic travel control system according to claim 2, characterized in that: A first throttling element is also provided on the pipeline between the third port of the flushing valve and the oil return port.

4. The hydraulic travel control system according to claim 1, characterized in that: The second port of the first flow dividing and combining valve is also connected to the fourth port of the first flow dividing and combining valve through a second throttling member; the second port of the second flow dividing and combining valve is also connected to the fourth port of the second flow dividing and combining valve through a third throttling member.

5. The hydraulic travel control system according to claim 1, characterized in that: The second port of the first flow dividing and collecting valve is also connected to the fourth port of the first flow dividing and collecting valve through the first one-way valve and the second one-way valve; the second port of the second flow dividing and collecting valve is also connected to the fourth port of the second flow dividing and collecting valve through the third one-way valve and the fourth one-way valve; The connection point between the first one-way valve and the second one-way valve, and the connection point between the third one-way valve and the fourth one-way valve are both connected to the oil replenishment pump integrated in the travel pump through the oil replenishment port.

6. The hydraulic travel control system according to any one of claims 1 to 5, characterized in that: The system further comprises a first pressure sensor and a second pressure sensor, wherein the first pressure sensor is used to detect the pressure of the port A of the travel pump, and the second pressure sensor is used to detect the pressure of the port B of the travel pump.

7. A high-altitude working vehicle, characterized in that: The vehicle comprises the hydraulic travel control system according to any one of claims 1 to 6.

8. A hydraulic travel control method, characterized in that: Applied to the hydraulic travel control system according to any one of claims 1 to 6, the control method comprises: When moving forward, the oil flows from the A port of the travel pump into the third port of the first flow-dividing and collecting valve and the third port of the second flow-dividing and collecting valve; then the oil is divided in equal proportion to the A port of the left rear travel motor and the A port of the left front travel motor through the second port and the fourth port of the first flow-dividing and collecting valve, and the oil is divided in equal proportion to the B port of the right rear travel motor and the B port of the right front travel motor through the second port and the fourth port of the second flow-dividing and collecting valve; the oil flows back to the B port of the travel pump after passing through the left rear travel motor, the left front travel motor, the right rear travel motor and the right front travel motor; When moving backward, the oil flows directly from the B port of the travel pump into the B port of the left rear travel motor, the B port of the left front travel motor, the A port of the right rear travel motor and the A port of the right front travel motor; the oil flows into the second port of the first diverter-collecting valve after passing through the left rear travel motor, the oil flows into the fourth port of the first diverter-collecting valve after passing through the left front travel motor, the oil flows into the second port of the second diverter-collecting valve after passing through the right rear travel motor, and the oil flows into the fourth port of the second diverter-collecting valve after passing through the right front travel motor; finally, the oil flows back to the A port of the travel pump through the first diverter-collecting valve and the second diverter-collecting valve.

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