Hydraulic steering system, aerial work equipment, and steering control method

Abstract

The present invention discloses a hydraulic steering system, aerial work equipment, and a steering control method, and relates to the technical field of aerial work equipment. The hydraulic steering system includes: an axle control valve group for controlling the steering of the steering wheel; a brake dual-speed control valve group, which is provided with a brake control valve for controlling the braking of the steering wheel; an oil source power assembly; a first connecting oil circuit, one end of which is connected to the oil inlet end of the axle control valve group connected to the oil source power assembly, and the other end is connected to the oil inlet end of the brake control valve; when the oil source power assembly delivers hydraulic oil to the axle control valve group, the hydraulic oil entering the axle control valve group is divided into one path to the first connecting oil circuit, so that the brake control valve controls the steering wheel to release the brake. The hydraulic steering system of the present invention can effectively reduce the friction between the steering wheel and the ground during the steering process, reduce the force acting on the steering cylinder when the steering wheel is turning, and improve the response speed and synchronization of the steering of the left and right steering wheels.

Description

Technical Field

[0001] The present invention relates to the technical field of aerial work equipment, and more specifically, to a hydraulic steering system. Furthermore, the present invention also relates to aerial work equipment including the hydraulic steering system and a steering control method applied to the aerial work equipment. Background Art

[0002] Aerial work platform models are heavy and have wide wheels. When the aerial work platform turns on the spot, the braked tires and the ground produce sliding friction at a certain angle. The sliding friction causes the tires to be subjected to greater steering pressure during the steering process; higher in-place steering pressure can easily lead to slow response when turning on the spot, and poor steering synchronization between the left and right tires.

[0003] In summary, how to reduce the steering pressure when the aerial work platform turns in situ is a problem that urgently needs to be solved by those skilled in the art. Summary of the Invention

[0004] In view of this, the purpose of the present invention is to provide a hydraulic steering system, which can deliver hydraulic oil to the braking dual-speed control valve group through the first connecting oil circuit during the actual steering process, and control the steering wheel to release the brake through the braking dual-speed control valve group, so that the sliding friction between the steering wheel and the ground during the steering process is at least partially converted into rolling friction, reducing the steering pressure when the aerial work platform is turning in place, and improving the steering response speed and synchronization of the left steering wheel and the right steering wheel.

[0005] Another object of the present invention is to provide an aerial work equipment including the above-mentioned hydraulic steering system and a steering control method applied to the above-mentioned aerial work equipment.

[0006] In order to achieve the above object, the present invention provides the following technical solutions:

[0007] A hydraulic steering system is applied to aerial work equipment, wherein the aerial work equipment includes a steering wheel; the hydraulic steering system includes:

[0008] A wheel axle control valve group, used for controlling the steering of the steering wheel;

[0009] A brake dual-speed control valve group is provided with a brake control valve for controlling the braking of the steering wheel;

[0010] An oil source power assembly, used for providing hydraulic oil to the axle control valve group and the brake dual-speed control valve group;

[0011] a first connecting oil circuit, one end of which is connected to the oil inlet end of the wheel axle control valve group connected to the oil source power component, and the other end of which is connected to the oil inlet end of the brake control valve of the brake dual-speed control valve group;

[0012] When the oil source power assembly delivers hydraulic oil to the axle control valve group, the hydraulic oil entering the axle control valve group is divided into one path to the first connecting oil path, so that the brake control valve controls the steering wheel to release the brake.

[0013] Optionally, it further comprises a travel control valve group and a second connecting oil circuit connecting the travel control valve group and the oil inlet end of the brake dual-speed control valve group, wherein the travel control valve group is used to control the flow of hydraulic oil flowing to different steering wheels;

[0014] A first one-way valve is provided at one end of the second connecting oil circuit connected to the brake dual-speed control valve group to prevent the hydraulic oil flowing into the brake dual-speed control valve group from the first connecting oil circuit from flowing into the travel control valve group through the first one-way valve.

[0015] Optionally, a second one-way valve is provided at one end of the first connecting oil circuit connected to the brake dual-speed control valve group to prevent the hydraulic oil from flowing from the second one-way valve to the oil source power assembly.

[0016] Optionally, the oil source power assembly includes a gear pump or a variable displacement pump.

[0017] A high-altitude working equipment comprises an equipment body, any one of the above-mentioned hydraulic steering systems, and a detection device for detecting the tilt angle of the equipment body.

[0018] Optionally, the detection device includes a first detection device for detecting the tilt angle of the device body in the front-to-back direction and a second detection device for detecting the tilt angle of the device body in the left-to-right direction.

[0019] Optionally, the detection device includes a tilt sensor and / or a tilt switch.

[0020] A steering control method, applied to any of the above-mentioned aerial work equipment, the steering control method comprising:

[0021] Obtaining the tilt angle of the device body;

[0022] Determine whether the inclination angle of the equipment body is less than 5°. If so, control the wheel axle control valve group to operate so that the steering wheel turns, and at the same time control the brake control valve in the brake dual-speed control valve group to be energized to release the brake of the steering wheel; if not, control the wheel axle control valve group to operate so that the steering wheel turns, and at the same time control the brake control valve in the brake dual-speed control valve group to be de-energized to put the steering wheel in a braking state.

[0023] A steering control method is applied to the above-mentioned aerial work equipment, and the steering control method includes:

[0024] Acquire a first tilt angle detected by the first detection device and a second tilt angle detected by the second detection device;

[0025] Determine whether any of the first tilt angle and the second tilt angle has a value greater than or equal to 5°. If so, control the wheel axle control valve group to operate so that the steering wheel steers, and simultaneously control the brake control valve in the brake dual-speed control valve group to be energized so that the steering wheel is in a braking state; if not, control the wheel axle control valve group to operate so that the steering wheel steers, and simultaneously control the brake control valve in the brake dual-speed control valve group to be energized so as to release the brake on the steering wheel.

[0026] In the process of using the hydraulic steering system provided by the present invention, when it is necessary to control the steering of the aerial work equipment, it is necessary to control the steering of the steering wheel through the wheel axle control valve group. In the process of steering the steering wheel, the oil source power component is required to provide hydraulic oil to the wheel axle control valve group. A part of the hydraulic oil supplied to the wheel axle control valve group by the oil source power component enters the wheel axle control valve group, and the other part is input into the brake control valve of the brake dual-speed control valve group through the first connecting oil circuit. The brake control valve controls the steering wheel to release the brake. In the process of steering the steering wheel, since the steering wheel can rotate at the same time, there is rolling friction between the steering wheel and the ground. Compared with the sliding friction between the steering wheel and the ground in the prior art, the friction between the steering wheel and the ground can be effectively reduced during the steering process, so that the force acting on the steering cylinder when the steering wheel is steering is reduced, which is beneficial to improving the response speed and synchronization of the steering of the left steering wheel and the right steering wheel.

[0027] The present invention also provides aerial work equipment including the hydraulic steering system and a steering control method applied to the aerial work equipment. BRIEF DESCRIPTION OF THE DRAWINGS

[0028] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the following briefly introduces the drawings required for use in the embodiments or the description of the prior art. Obviously, the drawings described below are merely embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on the provided drawings without paying any creative work.

[0029] Figure 1 This is a structural diagram of a specific embodiment 1 of the hydraulic steering system provided by the present invention;

[0030] Figure 2 This is a structural diagram of a specific embodiment 2 of the hydraulic steering system provided by the present invention;

[0031] Figure 3This is a structural diagram of a specific embodiment of the steering control method provided by the present invention.

[0032] Figure 1-3 middle:

[0033] 1 is the axle control valve group, 11 is the reversing valve, 12 is the left front steering cylinder, 13 is the right front steering cylinder, 14 is the left rear steering cylinder, 15 is the right rear steering cylinder, 2 is the brake dual-speed control valve group, 21 is the brake control valve, 31 is the gear pump, 32 is the variable pump, 4 is the first connecting oil circuit, 5 is the first one-way valve, 6 is the second connecting oil circuit, 7 is the second one-way valve, 8 is the travel control valve group, 91 is the left front motor, 92 is the right front motor, 93 is the left rear motor, and 94 is the right rear motor. DETAILED DESCRIPTION

[0034] The following will clearly and completely describe the technical solutions in the embodiments of the present invention in conjunction with the accompanying drawings. 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 making creative efforts are within the scope of protection of the present invention.

[0035] The core of the present invention is to provide a hydraulic steering system. During the actual steering process, hydraulic oil can be delivered to the braking dual-speed control valve group through the first connecting oil circuit, and the braking dual-speed control valve group can be used to control the steering wheel to release the brake, so that the sliding friction between the steering wheel and the ground during the steering process is at least partially converted into rolling friction, reducing the steering pressure when the aerial work platform is turning in place, and improving the steering response speed and synchronization of the left and right steering wheels.

[0036] Another core of the present invention is to provide an aerial work equipment including the above-mentioned hydraulic steering system and a steering control method applied to the above-mentioned aerial work equipment.

[0037] Please refer to Figures 1 to 3 .

[0038] This specific embodiment discloses a hydraulic steering system, which is applied to aerial work equipment, which includes a steering wheel; the hydraulic steering system includes: an axle control valve group 1, which is used to control the steering of the steering wheel; a brake dual-speed control valve group 2, which is provided with a brake control valve 21 for controlling the braking of the steering wheel; an oil source power component, which is used to provide hydraulic oil to the axle control valve group 1 and the brake dual-speed control valve group 2; a first connecting oil circuit 4, one end of which is connected to the oil inlet end of the axle control valve group 1 connected to the oil source power component, and the other end is connected to the oil inlet end of the brake control valve 21 of the brake dual-speed control valve group 2; when the oil source power component delivers hydraulic oil to the axle control valve group 1, the hydraulic oil entering the axle control valve group 1 is divided into one path to the first connecting oil circuit 4, so that the brake control valve 21 controls the steering wheel to release the brake.

[0039] like Figure 1 As shown, the axle control valve group 1 includes four reversing valves 11 respectively connected to the left front steering cylinder 12, the right front steering cylinder 13, the left rear steering cylinder 14, and the right rear steering cylinder 15. The oil source power component is provided with a gear pump 31. In the process of supplying oil to the axle control valve group 1, the hydraulic oil flowing out of the gear pump 31 enters the reversing valve 11, and part of the hydraulic oil enters the brake dual-speed control valve group 2 through the first connecting oil circuit 4 and flows to the brake control valve 21.

[0040] It should be noted that in the hydraulic steering system in this specific embodiment, the left front steering cylinder 12, the right front steering cylinder 13, the left rear steering cylinder 14, and the right rear steering cylinder 15 are respectively corresponded to by different reversing valves 11. During the actual control process, the two front wheels can be steered separately, or the two rear wheels can be steered separately, or the front and rear wheels can be steered in the same direction at the same time, or the front and rear wheels can be steered in different directions at the same time, which is determined according to the actual situation.

[0041] In the process of using the hydraulic steering system provided by this specific embodiment, when it is necessary to control the steering of the aerial work equipment, it is necessary to control the steering of the steering wheel through the wheel axle control valve group 1. During the steering process of the steering wheel, the oil source power component is required to provide hydraulic oil to the wheel axle control valve group 1. Part of the hydraulic oil supplied to the wheel axle control valve group 1 by the oil source power component enters the wheel axle control valve group 1, and the other part is input into the brake control valve 21 of the brake dual-speed control valve group 2 through the first connecting oil circuit 4. The brake control valve 21 controls the steering wheel to release the brake. During the steering process of the steering wheel, since the steering wheel can rotate at the same time, there is rolling friction between the steering wheel and the ground. Compared with the sliding friction between the steering wheel and the ground in the prior art, the friction between the steering wheel and the ground during the steering process can be effectively reduced, so that the force acting on the steering cylinder when the steering wheel is turning is reduced, which is beneficial to improving the response speed and synchronization of the steering of the left steering wheel and the right steering wheel.

[0042] In a specific embodiment, the hydraulic steering system also includes a travel control valve group 8 and a second connecting oil circuit 6 connecting the travel control valve group 8 and the oil inlet end of the brake dual-speed control valve group 2. The travel control valve group 8 is used to control the flow of hydraulic oil flowing to different steering wheels; a first one-way valve 5 is provided at one end of the second connecting oil circuit 6 connected to the brake dual-speed control valve group 2 to prevent the hydraulic oil flowing from the first connecting oil circuit 4 into the brake dual-speed control valve group 2 from flowing into the travel control valve group 8 through the first one-way valve 5.

[0043] After the hydraulic oil enters the brake dual-speed control valve group 2 from the first connecting oil circuit 4, part of the hydraulic oil will enter the second connecting oil circuit 6. The setting of the first one-way valve 5 can prevent the hydraulic oil flowing out of the first connecting oil circuit 4 from entering the walking control valve group 8 through the second connecting oil circuit 6, thereby avoiding affecting the walking action controlled by the walking control valve group 8 during the steering process.

[0044] like Figure 1 As shown, the hydraulic steering system is provided with a left front motor 91, a right front motor 92, a left rear motor 93, and a right rear motor 94, and the hydraulic oil flows into the left front motor 91, the right front motor 92, the left rear motor 93, and the right rear motor 94 respectively through the travel control valve group 8.

[0045] Based on the above embodiment, a second one-way valve 7 can be provided at one end of the first connecting oil circuit 4 connected to the brake dual-speed control valve group 2 to prevent the hydraulic oil from flowing from the second one-way valve 7 to the oil source power assembly.

[0046] During actual use, when the walking control valve group 8 is working, it is necessary to divert part of the hydraulic oil to the braking two-speed control valve group 2. This part of the hydraulic oil enters the braking two-speed control valve group 2 through the second connecting oil circuit 6. When the hydraulic oil flowing from the second connecting oil circuit 6 to the braking two-speed control valve group 2 enters the first connecting oil circuit 4, under the action of the second one-way valve 7, the hydraulic oil can be prevented from flowing to the oil source power component.

[0047] like Figure 2 As shown, the oil source power assembly can include a variable pump 32, which is suitable for automatically controlled aerial work equipment.

[0048] In addition to the above-mentioned hydraulic steering system, the present invention also provides an aerial work equipment including the hydraulic steering system disclosed in the above-mentioned embodiment, which includes an equipment body, any of the above-mentioned hydraulic steering systems and a detection device for detecting the tilt angle of the equipment body.

[0049] The detection device may include a first detection device for detecting the tilt angle of the device body in the front-to-back direction and a second detection device for detecting the tilt angle of the device body in the left-to-right direction; of course, the detection device may also be of other numbers, or detect the tilt angles in multiple directions, which is determined according to actual conditions and will not be elaborated here.

[0050] The detection device may include a tilt sensor and / or a tilt switch.

[0051] In addition to the above-mentioned aerial work equipment, the present invention also provides a steering control method, which is applied to the above-mentioned aerial work equipment. The steering control method includes:

[0052] Step S1, obtaining the tilt angle of the device body;

[0053] Step S2, determine whether the inclination angle of the equipment body is less than 5°. If so, control the wheel axle control valve group 1 to operate to make the steering wheel turn, and at the same time control the brake control valve 21 in the brake dual-speed control valve group 2 to be energized to release the brake of the steering wheel; if not, control the wheel axle control valve group 1 to operate to make the steering wheel turn, and at the same time control the brake control valve 21 in the brake dual-speed control valve group 2 to be de-energized to put the steering wheel in a braking state.

[0054] In the above step S2, when the inclination angle of the equipment body is less than 5°, the braking of the steering wheel can be released during the steering process, so that the steering pressure can be reduced, the steering response speed can be increased, and the service life of the steering cylinder can be increased while the size of the steering cylinder remains unchanged, or the size of the steering cylinder can be reduced while the steering pressure remains unchanged, the structural space can be optimized, and the procurement cost of the cylinder can be reduced; when the inclination angle of the equipment body is greater than or equal to 5°, the braking of the steering wheel does not need to be released during the steering process to avoid the aerial work equipment from sliding.

[0055] When the detection device includes a first detection device for detecting the tilt angle of the device body in the front-back direction and a second detection device for detecting the tilt angle of the device body in the left-right direction, the steering control method includes:

[0056] Step S01, obtaining a first tilt angle detected by a first detection device and a second tilt angle detected by a second detection device;

[0057] Step S02, determine whether there is a value greater than or equal to 5° between the first tilt angle and the second tilt angle. If so, control the wheel axle control valve group 1 to operate to make the steering wheel turn, and at the same time control the brake control valve 21 in the brake dual-speed control valve group 2 to be powered off, so that the steering wheel is in a braking state; if not, control the wheel axle control valve group 1 to operate to make the steering wheel turn, and at the same time control the brake control valve 21 in the brake dual-speed control valve group 2 to be powered on, so as to release the brake on the steering wheel.

[0058] The “first” and “second” in the first connecting oil circuit 4 and the second connecting oil circuit 6 and the first one-way valve 5 and the second one-way valve 7 mentioned in this application document are only for distinguishing the different positions and there is no distinction in order.

[0059] The various embodiments in this specification are described in a progressive manner, and each embodiment focuses on the differences from other embodiments. The same or similar parts between the various embodiments can be referenced to each other. Any combination of all the embodiments provided by the present invention is within the scope of protection of this invention and will not be described in detail here.

[0060] The hydraulic steering system, aerial work equipment, and steering control method provided by the present invention are introduced in detail above. Specific examples are used herein to illustrate the principles and implementation methods of the present invention. The description of the above embodiments is only used to help understand the method of the present invention and its core concept. It should be pointed out that for ordinary technicians in this technical field, without departing from the principles of the present invention, the present invention can also be improved and modified in a number of ways, and these improvements and modifications also fall within the scope of protection of the claims of the present invention.

Claims

1. A hydraulic steering system, characterized in that: Applicable to aerial work equipment, the aerial work equipment includes a steering wheel; the hydraulic steering system includes: A wheel axle control valve group (1), used for controlling the steering of the steering wheel; A braking dual-speed control valve group (2) is provided with a braking control valve (21) for controlling the braking of the steering wheel; An oil source power assembly, used for providing hydraulic oil to the axle control valve group (1) and the brake dual-speed control valve group (2); A first connecting oil circuit (4), one end of which is connected to the oil inlet end of the wheel axle control valve group (1) connected to the oil source power component, and the other end of which is connected to the oil inlet end of the brake control valve (21) of the brake dual-speed control valve group (2); When the oil source power assembly delivers hydraulic oil to the axle control valve group (1), the hydraulic oil entering the axle control valve group (1) is divided into one path to the first connecting oil path (4), so that the brake control valve (21) controls the steering wheel to release the brake; It also includes a travel control valve group (8) and a second connecting oil circuit (6) connecting the travel control valve group (8) and the oil inlet end of the brake dual-speed control valve group (2), wherein the travel control valve group (8) is used to control the flow of hydraulic oil flowing to different steering wheels; A first one-way valve (5) is provided at one end of the second connecting oil circuit (6) connected to the brake dual-speed control valve group (2) to prevent the hydraulic oil flowing into the brake dual-speed control valve group (2) from the first connecting oil circuit (4) from flowing into the travel control valve group (8) via the first one-way valve (5); The oil source power assembly includes a gear pump (31) or a variable displacement pump (32).

2. The hydraulic steering system according to claim 1, characterized in that: One end of the first connecting oil circuit (4) connected to the brake dual-speed control valve group (2) is provided with a second one-way valve (7) to prevent the hydraulic oil from flowing from the second one-way valve (7) to the oil source power assembly.

3. A high-altitude working equipment, characterized in that: It comprises an equipment body, the hydraulic steering system according to any one of claims 1 to 2, and a detection device for detecting the tilt angle of the equipment body.

4. The aerial work equipment according to claim 3, characterized in that: The detection device includes a first detection device for detecting an inclination angle of the device body in a front-to-back direction and a second detection device for detecting an inclination angle of the device body in a left-to-right direction.

5. The aerial work equipment according to claim 4, characterized in that: The detection device includes a tilt sensor and / or a tilt switch.

6. A steering control method, characterized in that: Applied to the aerial work equipment according to any one of claims 3 to 5, the steering control method comprises: Obtaining the tilt angle of the device body; Determine whether the tilt angle of the device body is less than 5°. If so, control the axle control valve group (1) to operate so as to steer the steering wheel, and simultaneously control the brake control valve (21) in the brake dual-speed control valve group (2) to be energized so as to release the brake of the steering wheel; if not, control the axle control valve group (1) to operate so as to steer the steering wheel, and simultaneously control the brake control valve (21) in the brake dual-speed control valve group (2) to be de-energized so as to put the steering wheel in a braking state.

7. A steering control method, characterized in that: Applied to the aerial work equipment according to claim 4 or 5, the steering control method comprises: Acquire a first tilt angle detected by the first detection device and a second tilt angle detected by the second detection device; It is determined whether the first tilt angle and the second tilt angle have a value greater than or equal to 5°. If so, the wheel axle control valve group (1) is controlled to operate so as to steer the steering wheel, and the brake control valve (21) in the brake dual-speed control valve group (2) is controlled to be de-energized so as to put the steering wheel in a braking state. If not, the wheel axle control valve group (1) is controlled to operate so as to steer the steering wheel, and the brake control valve (21) in the brake dual-speed control valve group (2) is controlled to be energized so as to release the brake on the steering wheel.

Images