Control system and control method for landing legs of crawler scissor type overhead working truck

Abstract

The invention provides a control system and a control method for a landing leg of a crawler scissor type overhead working truck, the control system comprises a hydraulic oil tank, a gear pump, a speed reducer motor and a landing leg oil cylinder, a walking main oil inlet pipeline and a landing leg main oil inlet pipeline are respectively connected with the speed reducer motor and the landing leg oil cylinder through a walking control valve group and a landing leg control valve group; a priority valve is arranged on a pipeline of an oil outlet of the gear pump, and a valve element of the priority valve is connected with a walking main oil return pipeline arranged between the walking control valve set and the hydraulic oil tank through an electromagnetic switch control valve. A switch reversing valve is arranged on the supporting leg main oil inlet pipeline and is a three-position four-way electromagnetic valve. Hydraulic pressure is adopted as power to drive the speed reducer motor to drive the walking mechanism to act, the priority valve is arranged, oil liquid preferentially meets the working condition of retracting the supporting legs in the running process, a more economical scheme is used for achieving component type selection, reducing energy consumption, increasing endurance and achieving the function of retracting the supporting legs while the vehicle runs normally.

Description

Technical Field

[0001] The invention relates to a control system and a control method for outriggers of a crawler scissor-type aerial work vehicle, belonging to the technical field of aerial work platforms. Background Art

[0002] The existing crawler scissor-type aerial work platforms on the market generally use travel motors to directly drive their travel systems. Considering that crawler models often involve some harsh working conditions, their reliability is not as good as that of hydraulic motors in muddy environments.

[0003] The crawler scissors on the domestic market are mainly electric-driven, and there are fewer hydraulic-driven products. The main reasons for this are as follows.

[0004] First of all, when the crawler scissor-type aerial work vehicle with outriggers finishes its work and is ready to move to another site, it will have the function of retracting the outriggers while walking to avoid the operator forgetting to retract the outrigger cylinder to a safe position before driving, causing the outriggers to collide and be damaged. The electric-driven crawler scissor-type aerial work vehicle on the market has an electronically controlled walking system and hydraulically controlled outriggers, which can operate simultaneously without interfering with each other. However, the hydraulic-driven crawler scissor-type aerial work vehicle has both actions controlled by hydraulics, so there are problems with component selection and flow distribution that need to be solved.

[0005] Secondly, since the walking system and the outrigger system need to work at the same time, the required flow rate will be very large, while the flow rate required for the lifting process of the working platform is relatively small. If the fixed-displacement gear pump is used for the whole machine, it will cause a waste of capacity when performing the lifting action under the working conditions of walking and extending the outriggers, and the gear pump and the motor work in the low-efficiency speed area, and the endurance of the whole machine is poor. If a variable piston pump is used, the problem of large differences in the flow rates required for the above different working conditions can be solved, but the size and cost of the variable pump far exceed the gear pump, so it cannot be used. Summary of the invention

[0006] Purpose of the invention: In view of the deficiencies in the prior art, the present invention provides a control system and method for the outriggers of a crawler scissor-type aerial work vehicle. By setting an electromagnetic switch valve, it is possible to independently select whether to perform combined control of the walking mechanism and the outrigger mechanism. By setting a priority valve, the outriggers can be controlled to be retracted simultaneously when the vehicle starts walking. Both walking and outrigger retraction are achieved through a hydraulic system, which has a low cost and better driving stability on muddy roads.

[0007] Technical solution: A crawler scissor-type aerial work vehicle outrigger control system includes a hydraulic oil tank, a gear pump, a reducer motor and an outrigger oil cylinder. The gear pump oil outlet pipeline is divided into two branches, namely a walking main oil inlet pipeline and an outrigger main oil inlet pipeline. The walking main oil inlet pipeline and the outrigger main oil inlet pipeline are connected to the reducer motor and the outrigger oil cylinder through a walking control valve group and an outrigger control valve group respectively. A priority valve is arranged on the pipeline of the oil outlet of the gear pump, and the valve core of the priority valve is connected to the main oil return pipeline of the travel arranged between the travel control valve group and the hydraulic oil tank through the electromagnetic switch control valve, and the electromagnetic switch control valve is in a two-way conduction state in the power-off state; A switch reversing valve is arranged on the main oil inlet pipeline of the outrigger, and the switch reversing valve is a three-position four-way solenoid valve.

[0008] The present invention adopts hydraulic power to drive the reducer motor to drive the walking mechanism to move. Compared with the walking mechanism driven by an electric motor, it has a wider range of applications and can be stably used in wet and muddy working environments. By setting a priority valve, it can ensure that the oil will give priority to the working conditions of the retracting and outrigger legs during driving. A more economical solution is used to solve the component selection, which not only ensures the reduction of energy consumption and the increase of endurance, but also realizes the function of retracting the outriggers while the vehicle is driving normally.

[0009] The outrigger control valve group includes two groups of front outrigger control valve groups and rear outrigger control valve groups with the same structure. Any front outrigger control valve group or rear outrigger control valve group includes an electromagnetic switch valve installed on the left outrigger oil cylinder and the right outrigger oil cylinder, and an outrigger switch valve arranged between the two electromagnetic switch valves and the switch reversing valve.

[0010] By respectively arranging two groups of corresponding outrigger control valve groups on the front and rear outrigger cylinders, the control of the front and rear outrigger cylinders can be achieved, and the action of the outrigger cylinders on one side can be shielded through the outrigger switch valve, so that only the front or rear outrigger cylinders can be controlled to lift or lower separately. Under the condition of the same oil flow rate, the outrigger cylinder extension or retraction action can be completed faster.

[0011] The electromagnetic switch valve is arranged on the oil circuit corresponding to the large chamber of the outrigger oil cylinder, and also includes a hydraulically controlled one-way valve arranged between the electromagnetic switch valve and the outrigger switch valve. The hydraulically controlled one-way valve is arranged on the oil circuit corresponding to the large chamber of the outrigger oil cylinder, and is connected to the oil circuit corresponding to the small chamber of the outrigger oil cylinder.

[0012] In order to ensure that the outrigger oil cylinder can provide stable support after being extended, an electromagnetic switch valve is set. When the oil cylinder needs to move, the electromagnetic switch valve is energized and the oil circuit is connected. When it is not energized, it is in a blocked state. After the outrigger oil cylinder is extended, the electromagnetic switch valve is not energized to achieve stable support. A hydraulically controlled one-way valve is set to ensure stable support even when the electromagnetic switch valve fails to block.

[0013] The travel control valve group includes an electromagnetic proportional reversing valve and a pressure compensation valve arranged on the oil circuit between the electromagnetic proportional reversing valve and the reducer motor.

[0014] In order to achieve hydraulically driven walking, an electromagnetic proportional reversing valve and a pressure compensation valve are set so that the hydraulic oil output to the reducer motor is only controlled by the opening size of the electromagnetic proportional reversing valve, with stable operation and high reliability.

[0015] An overflow valve is arranged between the main traveling oil inlet pipeline and the main traveling oil return pipeline, and a one-way valve is arranged between the overflow valve and the main traveling oil inlet pipeline.

[0016] In order to protect the hydraulic system, an overflow valve is set. When the system pressure value is too high, the excess hydraulic oil is returned to the tank through the overflow valve.

[0017] A three-way flow valve is provided between the main traveling oil inlet pipeline and the main traveling oil return pipeline.

[0018] The starting pressure value of the three-way flow valve is lower than that of the relief valve. When the system pressure value is too large, it will overflow from the three-way relief valve first, making the pressure value in the system smaller than the pressure value overflowing through the relief valve, resulting in less energy loss and achieving energy-saving effect.

[0019] A control method for a crawler scissor-type aerial work vehicle outrigger control system, The control solenoid switch control valve is energized, and the working condition is divided into fully supported working condition and incompletely supported working condition according to the outrigger status; The vehicle completes the supporting action, the outrigger oil cylinders are extended and in contact with the ground, entering the fully supported working condition, the operator issues a walking command, the electromagnetic proportional reversing valve is not energized, the walking mechanism does not move, the operator issues a retraction command for the outrigger oil cylinders, and the switch reversing valve is energized; The outrigger cylinders retract to leave the ground and enter the partially supported working condition. The operator issues a travel command, the electromagnetic proportional directional valve is energized, the whole system determines the direction of the travel command, and controls the outrigger switch valves in the opposite direction to be energized, so that the outrigger cylinders in the travel direction are retracted first. 4 to 6 seconds after the operator issues the travel command, the outrigger switch valves on the other side are not energized and reset to the passage position, and all the outrigger cylinders are retracted.

[0020] The fully supported working condition is specifically as follows: a detection switch is installed at the connection between the frame and the outrigger cylinder, and the outrigger cylinder has an extending movement. When the outrigger cylinder is extended and supported on the ground, the cylinder barrel moves up and contacts the detection switch. When the cylinder barrels of the front and rear outrigger cylinders both move up and contact the detection switch, the system determines that the current condition is a fully supported working condition.

[0021] The incomplete support working condition is specifically: the outrigger oil cylinder has an extension action, and at least one outrigger oil cylinder is not in contact with the detection switch.

[0022] Beneficial effects: The present invention adopts hydraulic power to drive the reducer motor to drive the travel mechanism. Compared with the travel mechanism driven by an electric motor, it has a wider range of applications and can be stably used in wet and muddy working environments. By setting a priority valve, it can ensure that the oil will give priority to the working conditions of the retracting and outrigger legs during driving. A more economical solution is used to solve the component selection, which not only ensures the reduction of energy consumption and increase of endurance, but also realizes the function of retracting the outriggers while the vehicle is driving normally. BRIEF DESCRIPTION OF THE DRAWINGS

[0023] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings required for use in the embodiments or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are only embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on the provided drawings without paying creative work.

[0024] Figure 1 It is the hydraulic principle diagram of the present invention. DETAILED DESCRIPTION

[0025] The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions 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.

[0026] In the description of the present invention, it is necessary to understand that the terms "up", "down", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inside", "outside", etc., indicating the orientation or position relationship are based on the orientation or position relationship shown in the drawings, and are only for the convenience of describing the present invention and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as a limitation on the present invention.

[0027] In the present invention, unless otherwise clearly specified and limited, a first feature being "above" or "below" a second feature may include that the first and second features are in direct contact, or may include that the first and second features are not in direct contact but are in contact through another feature between them. Moreover, a first feature being "above", "above" and "above" a second feature includes that the first feature is directly above and obliquely above the second feature, or simply indicates that the first feature is higher in level than the second feature. A first feature being "below", "below" and "below" a second feature includes that the first feature is directly below and obliquely below the second feature, or simply indicates that the first feature is lower in level than the second feature.

[0028] like Figure 1 As shown, a crawler scissor type aerial work vehicle outrigger control system comprises a hydraulic oil tank 1, a gear pump 2, a reducer motor 3 and an outrigger oil cylinder. The gear pump 2 oil outlet pipeline is divided into two branches, namely a walking main oil inlet pipeline and an outrigger main oil inlet pipeline. The walking main oil inlet pipeline and the outrigger main oil inlet pipeline are connected to the reducer motor 3 and the outrigger oil cylinder through a walking control valve group 4 and an outrigger control valve group 5 respectively. A priority valve 6 is provided on the pipeline of the oil outlet of the gear pump 2, and the valve core of the priority valve 6 is connected to the main oil return pipeline of the travel arranged between the travel control valve group 4 and the hydraulic oil tank 1 through the electromagnetic switch control valve 7. In the power-off state, the electromagnetic switch control valve 7 is in a two-way conduction state; A switch reversing valve 8 is arranged on the main oil inlet pipeline of the outrigger, and the switch reversing valve 8 is a three-position four-way solenoid valve.

[0029] The present invention adopts hydraulic power to drive the reducer motor 3 to drive the walking mechanism to move. Compared with the walking mechanism driven by an electric motor, it has a wider range of applications and can be stably used in wet and muddy working environments. By setting a priority valve 6, it is ensured that the oil will give priority to the working conditions of the retracting and outrigger legs during driving. A more economical solution is used to solve the component selection, which not only ensures the reduction of energy consumption and the increase of endurance, but also realizes the function of retracting the outriggers while the vehicle is driving normally.

[0030] The outrigger control valve group 5 includes two groups of front outrigger control valve groups 51 and rear outrigger control valve groups 52 with the same structure. Any front outrigger control valve group 51 or rear outrigger control valve group 52 includes an electromagnetic switch valve 53 installed on the left outrigger oil cylinder and the right outrigger oil cylinder, and an outrigger switch valve 54 arranged between the two electromagnetic switch valves 53 and the switch reversing valve 8.

[0031] By respectively arranging two groups of correspondingly controlled outrigger control valve groups 5 on the front and rear outrigger cylinders, control of the front and rear outrigger cylinders can be achieved, and the action of the outrigger cylinders on one side can be shielded through the outrigger switch valve 54, so that only the front or rear outrigger cylinders can be controlled to lift or lower separately. Under the condition of the same oil flow rate, the outrigger cylinder extension or retraction action can be completed more quickly.

[0032] The electromagnetic switch valve 53 is arranged on the oil circuit corresponding to the large chamber of the outrigger oil cylinder, and also includes a hydraulically controlled one-way valve 55 arranged between the electromagnetic switch valve 53 and the outrigger switch valve 54. The hydraulically controlled one-way valve 55 is arranged on the oil circuit corresponding to the large chamber of the outrigger oil cylinder, and is connected to the oil circuit corresponding to the small chamber of the outrigger oil cylinder.

[0033] In order to ensure that the outrigger oil cylinder can provide stable support after being extended, an electromagnetic switch valve 53 is provided. When the oil cylinder needs to be actuated, the electromagnetic switch valve 53 is energized and the oil circuit is connected. When it is not energized, it is in a blocked state. After the outrigger oil cylinder is extended, the electromagnetic switch valve 53 is not energized, thereby achieving stable support. A hydraulically controlled one-way valve 55 is provided, so that stable support can still be maintained when the electromagnetic switch valve 53 fails to be blocked.

[0034] The travel control valve group 4 includes an electromagnetic proportional reversing valve and a pressure compensation valve 9 arranged on the oil circuit between the electromagnetic proportional reversing valve and the reducer motor 3 .

[0035] In order to realize walking through hydraulic drive, an electromagnetic proportional reversing valve and a pressure compensation valve 9 are set, so that the hydraulic oil output to the reducer motor 3 is only controlled by the opening size of the electromagnetic proportional reversing valve, and the operation is stable and the reliability is high.

[0036] An overflow valve 10 is provided between the main traveling oil inlet pipeline and the main traveling oil return pipeline, and a one-way valve 101 is provided between the overflow valve 10 and the main traveling oil inlet pipeline.

[0037] In order to protect the hydraulic system, an overflow valve 10 is provided. When the system pressure value is too large, the excess hydraulic oil is returned to the oil tank through the overflow valve 10.

[0038] A three-way flow valve 102 is provided between the main traveling oil inlet pipeline and the main traveling oil return pipeline.

[0039] The starting pressure value of the three-way flow valve 102 is lower than that of the relief valve 10. When the system pressure value is too large, the three-way relief valve 10 will overflow first, so that the pressure value in the system is smaller than the pressure value overflowing through the relief valve 10, the energy loss is smaller, and the energy saving effect is achieved.

[0040] A control method for a crawler scissor-type aerial work vehicle outrigger control system, The electromagnetic switch control valve 7 is energized, and the outrigger status is divided into a fully supported working condition and an incompletely supported working condition; The vehicle completes the supporting action, the outrigger oil cylinders are extended and contact the ground, entering the fully supported working condition, the operator issues a walking command, the electromagnetic proportional reversing valve is not energized, the walking mechanism does not move, the operator issues a retraction command for the outrigger oil cylinders, and the switch reversing valve 8 is energized; The outrigger oil cylinders retract to leave the ground and enter the incomplete support condition. The operator issues a travel command, the electromagnetic proportional reversing valve is energized, the whole system determines the direction of the travel command, controls the outrigger switch valve 54 in the opposite direction to be energized, and the outrigger oil cylinders in the travel direction are retracted first. 4 to 6 seconds after the operator issues the travel command, the outrigger switch valve 54 on the other side is not energized and reset to the passage position, and the outrigger oil cylinders are all retracted.

[0041] The fully supported working condition is specifically as follows: a detection switch is installed at the connection between the frame and the outrigger cylinder, and the outrigger cylinder has an extending movement. When the outrigger cylinder is extended and supported on the ground, the cylinder barrel moves up and contacts the detection switch. When the cylinder barrels of the front and rear outrigger cylinders both move up and contact the detection switch, the system determines that the current condition is a fully supported working condition.

[0042] The incomplete support working condition is specifically: the outrigger oil cylinder has an extension action, and at least one outrigger oil cylinder is not in contact with the detection switch.

[0043] In this specification, each embodiment is described in a progressive manner, and each embodiment focuses on the differences from other embodiments. The same or similar parts between the embodiments can be referred to each other. For the device disclosed in the embodiment, since it corresponds to the method disclosed in the embodiment, the description is relatively simple, and the relevant parts can be referred to the method part.

[0044] The above description of the disclosed embodiments enables one skilled in the art to implement or use the present invention. Various modifications to these embodiments will be apparent to one skilled in the art, and the general principles defined herein may be implemented in other embodiments without departing from the spirit or scope of the present invention. Therefore, the present invention will not be limited to the embodiments shown herein, but rather to the widest scope consistent with the principles and novel features disclosed herein.

Claims

1. A crawler scissor lift aerial work vehicle outrigger control system, comprising a hydraulic oil tank (1), a gear pump (2), a reducer motor (3) and an outrigger oil cylinder, wherein the gear pump (2) has an oil outlet pipeline divided into two branches, namely a main oil inlet pipeline for traveling and a main oil inlet pipeline for outriggers, wherein the main oil inlet pipeline for traveling and the main oil inlet pipeline for outriggers are connected to the reducer motor (3) and the outrigger oil cylinder via a traveling control valve group (4) and an outrigger control valve group (5), respectively, and characterized in that: A priority valve (6) is provided on the pipeline of the oil outlet of the gear pump (2); the valve core of the priority valve (6) is connected to a main travel oil return pipeline provided between the travel control valve group (4) and the hydraulic oil tank (1) via an electromagnetic switch control valve (7); and the electromagnetic switch control valve (7) is in a two-way conduction state in a power-off state; A switch reversing valve (8) is provided on the main oil inlet pipeline of the outrigger, and the switch reversing valve (8) is a three-position four-way solenoid valve.

2. The crawler scissor type aerial work vehicle outrigger control system according to claim 1, characterized in that: The outrigger control valve group (5) comprises two groups of front outrigger control valve groups (51) and rear outrigger control valve groups (52) of identical structure, and any of the front outrigger control valve groups (51) or rear outrigger control valve groups (52) comprises electromagnetic switch valves (53) installed in the left outrigger oil cylinder and the right outrigger oil cylinder, and an outrigger switch valve (54) arranged between the two electromagnetic switch valves (53) and the switch reversing valve (8).

3. The crawler scissor type aerial work vehicle outrigger control system according to claim 2, characterized in that: The electromagnetic switch valve (53) is arranged on the oil circuit corresponding to the large chamber of the outrigger oil cylinder, and further comprises a hydraulically controlled one-way valve (55) arranged between the electromagnetic switch valve (53) and the outrigger switch valve (54); the hydraulically controlled one-way valve (55) is arranged on the oil circuit corresponding to the large chamber of the outrigger oil cylinder, and is in communication with the oil circuit corresponding to the small chamber of the outrigger oil cylinder.

4. The crawler scissor type aerial work vehicle outrigger control system according to claim 1, characterized in that: The travel control valve group (4) comprises an electromagnetic proportional reversing valve (41) and a pressure compensation valve (9) arranged in the oil circuit between the electromagnetic proportional reversing valve (41) and the reducer motor (3).

5. The crawler scissor type aerial work vehicle outrigger control system according to claim 1, characterized in that: A relief valve (10) is provided between the main traveling oil inlet pipeline and the main traveling oil return pipeline, and a check valve (101) is provided between the relief valve (10) and the main traveling oil inlet pipeline.

6. The crawler scissor type aerial work vehicle outrigger control system according to claim 1, characterized in that: A three-way flow valve (102) is provided between the main traveling oil inlet pipeline and the main traveling oil return pipeline.

7. A control method for a crawler scissor-type aerial work vehicle outrigger control system according to any one of claims 1 to 6, characterized in that: The electromagnetic switch control valve (7) is energized, and the outrigger state is divided into a fully supported working condition and an incompletely supported working condition; The vehicle completes the supporting action, the outrigger oil cylinders are extended and in contact with the ground, and enters the fully supported working condition. The operator issues a travel command, the electromagnetic proportional reversing valve is not energized, and the traveling mechanism does not move. The operator issues a retraction command for the outrigger oil cylinders, and the switch reversing valve (8) is energized; The outrigger oil cylinders are retracted to leave the ground and enter the incomplete support working condition. The operator issues a travel command, the electromagnetic proportional reversing valve is energized, the whole machine system determines the direction of the travel command, controls the outrigger switch valve (54) in the opposite direction to be energized, and the outrigger oil cylinders in the travel direction are retracted first. 4 to 6 seconds after the operator issues the travel command, the outrigger switch valve (54) on the other side is not energized and resets to the passage position, and the outrigger oil cylinders are all retracted.

8. The control method of the outrigger control system of the crawler scissor type aerial work vehicle according to claim 7, characterized in that: The fully supported working condition is specifically as follows: a detection switch is installed at the connection between the frame and the outrigger cylinder, and the outrigger cylinder has an extending movement. When the outrigger cylinder is extended and supported on the ground, the cylinder barrel moves up and contacts the detection switch. When the cylinder barrels of the front and rear outrigger cylinders both move up and contact the detection switch, the system determines that the current condition is a fully supported working condition.

9. The control method of the outrigger control system of the crawler scissor type aerial work vehicle according to claim 8, characterized in that: The incomplete support working condition is specifically: the outrigger oil cylinder has an extension action, and at least one outrigger oil cylinder is not in contact with the detection switch.

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