Hydraulic system of crawler-type aerial work platform

Abstract

The utility model relates to a hydraulic system of a crawler-type aerial work platform, which comprises an oil tank filled with hydraulic oil for providing hydraulic power; the first pump set is connected with the oil tank; the second pump set is connected with the oil tank, and the second pump set is parallel to the first pump set; the main valve set is connected with the first pump set and the second pump set, the first pump set and the second pump set supply oil to a walking mechanism of the crawler-type aerial work platform through the main valve set, and the first pump set and the second pump set achieve independent flow control over the walking mechanism of the crawler-type aerial work platform. According to the hydraulic system of the crawler-type aerial work platform, the first pump set and the second pump set specifically adopt the combination mode of the permanent magnet motors and the pumps, the permanent magnet motors and the pumps directly output flow to the executing mechanism, pressure loss caused by proportional valve opening adjustment is avoided, and therefore the system noise is low; and by adopting the design, the overall size of the aerial work platform is reduced, and the aerial work platform is convenient to package and transport.

Description

Technical Field

[0001] This utility model relates to the field of aerial work platform technology, and in particular to a hydraulic system for a tracked aerial work platform. Background Technology

[0002] Tracked aerial work platforms are a type of aerial work platform that uses tracked walking technology, enabling movement with millimeter-level precision. Rubber tracked self-propelled aerial work platforms are hydraulically driven and utilize hydraulic telescopic booms to raise the work platform to a certain height, allowing workers to perform various tasks. They are suitable for tasks such as cleaning curtain walls in creative venues, replacing and repairing lighting fixtures, power testing, substation maintenance, and tower repair in the power industry, as well as in the military, aerospace, and petroleum industries.

[0003] Among them, tracked aerial work platforms include multiple actuators such as walking and lifting, and the synchronicity of walking and the energy saving of the system are particularly important.

[0004] The hydraulic systems widely used in existing tracked aerial work platforms consist of a single motor, a single pump, and a proportional multi-way valve control. This configuration suffers from slightly insufficient synchronization accuracy between the left and right traveling wheels and is not energy-efficient. Furthermore, the existing traveling mechanism uses a series-wound motor with an iron-core rotor and a relatively thick silicon steel stator, resulting in high heat generation and consequently, high noise levels. Utility Model Content

[0005] Therefore, the technical problem to be solved by this utility model is to overcome the problems of imperfect hydraulic control, high energy consumption and the need to improve the operational stability of the hydraulic system in the existing tracked aerial work vehicle.

[0006] To solve the above-mentioned technical problems, this utility model provides a hydraulic system for a tracked aerial work platform, comprising: an oil tank filled with hydraulic oil to provide hydraulic power; a first pump group connected to the oil tank; a second pump group connected to the oil tank and running parallel to the first pump group; and a main valve group connecting the first and second pump groups. The first and second pump groups supply oil to the actuator of the tracked aerial work platform through the main valve group, and simultaneously supply oil to the walking mechanism of the tracked aerial work platform through the main valve group. The first and second pump groups respectively achieve independent flow control of the walking mechanism of the tracked aerial work platform. Specifically, the hydraulic system of this utility model for a tracked aerial work platform uses a combination of permanent magnet motors and pumps in both the first and second pump groups. Because permanent magnet motors are used, the pumps directly output flow to the actuators, eliminating pressure loss caused by proportional valve opening adjustments, thus resulting in lower system noise. Furthermore, this design reduces the overall size of the aerial work platform, facilitating packaging and transportation.

[0007] In one embodiment of the present invention, the tracked aerial work platform includes a first walking mechanism, a second walking mechanism, and an execution mechanism.

[0008] In one embodiment of this utility model, the main valve group includes a first check valve, a second check valve, a first solenoid directional valve, a second solenoid directional valve, a third solenoid directional valve, and a solenoid valve. The first pump group is connected to the first traveling mechanism through the first check valve, and the second pump group is connected to the second traveling mechanism through the second check valve. The first solenoid directional valve is disposed on the return oil line between the first traveling mechanism and the oil tank, the second solenoid directional valve is disposed on the return oil line between the second traveling mechanism and the oil tank, the third solenoid directional valve is disposed on the oil supply line between the first pump group, the second pump group, and the actuator, and the solenoid valve is disposed between the oil supply line of the first pump group and the second pump group to realize that the first pump group and the second pump group alternately supply oil to the actuator.

[0009] In one embodiment of this utility model, the first electromagnetic reversing valve, the second electromagnetic reversing valve, and the third electromagnetic reversing valve are all three-position four-way electromagnetic reversing valves.

[0010] In one embodiment of this utility model, the solenoid valve is a two-position two-way solenoid directional valve.

[0011] In one embodiment of the present invention, the main valve group further includes a pressure reducing valve and a fifth solenoid directional valve. The first traveling mechanism and the second traveling mechanism are both connected to the fifth solenoid directional valve. The pressure reducing valve is connected between the fifth solenoid directional valve and the oil supply line of the actuator, and the fifth solenoid directional valve is connected to the oil return line of the oil tank.

[0012] In one embodiment of this utility model, the fifth electromagnetic directional valve is a three-position three-way electromagnetic directional valve.

[0013] In one embodiment of this utility model, the oil return pipeline of the oil tank is connected to an oil return filter.

[0014] In one embodiment of this utility model, an oil inlet filter is connected to the oil inlet pipeline from the oil tank to the first pump group and the second pump group.

[0015] In one embodiment of this utility model, a sixth electromagnetic reversing valve and a first overflow valve are provided between the oil inlet pipe and the oil return pipe of the first pump group, and a seventh electromagnetic reversing valve and a second overflow valve are provided between the oil inlet pipe and the oil return pipe of the second pump group.

[0016] Compared with the prior art, the above-mentioned technical solution of this utility model has the following beneficial effects:

[0017] The hydraulic system of the tracked aerial work platform described in this utility model uses a first pump group and a second pump group, namely dual permanent magnet motors and dual pump control. By setting the motor speed, the flow output can be adjusted. This design ensures better synchronization accuracy of the left and right wheels, eliminates the need for closed-loop feedback, and provides good walking synchronization performance with less manual correction. It also achieves stepless speed regulation of the lifting, rotating, and swinging actuators, eliminating the need for additional emergency power units or emergency pump groups. The system noise is greatly reduced, reaching a maximum of about 65 decibels compared to ordinary equipment systems that exceed 75 decibels. Attached Figure Description

[0018] To make the content of this utility model easier to understand, the present utility model will be further described in detail below with reference to specific embodiments and accompanying drawings.

[0019] Figure 1 This is a hydraulic diagram of the hydraulic system of the tracked aerial work platform in a preferred embodiment of the present invention;

[0020] Figure 2 This is a block diagram of the hydraulic system of the tracked aerial work platform in a preferred embodiment of the present invention.

[0021] Explanation of reference numerals in the accompanying drawings: Oil tank 100, first pump group 200, second pump group 300, main valve group 400, first traveling mechanism 500, second traveling mechanism 600, actuator 700, first check valve 1, second check valve 2, first solenoid directional valve 3, second solenoid directional valve 4, third solenoid directional valve 5, solenoid valve 6, pressure reducing valve 7, fifth solenoid directional valve 8, return oil filter 9, inlet oil filter 10, sixth solenoid directional valve 11, first relief valve 12, seventh solenoid directional valve 13, second relief valve 14. Detailed Implementation

[0022] The present invention will be further described below with reference to the accompanying drawings and specific embodiments, so that those skilled in the art can better understand and implement the present invention. However, the embodiments are not intended to limit the present invention.

[0023] Reference Figure 1 , 2 As shown, the tracked aerial work platform includes a first traveling mechanism 500, a second traveling mechanism 600, and an actuator 700. The tracked aerial work platform has two independent traveling mechanisms on each side, namely the first traveling mechanism 500 and the second traveling mechanism 600, which are used for the movement and turning of the tracked aerial work platform. The actuator 700 is used to realize the lifting, rotation, and swinging movements of the tracked aerial work platform.

[0024] To optimize the movement of the tracked aerial work platform's walking mechanism and actuators, the hydraulic system of this utility model includes: an oil tank 100, a first pump group 200, a second pump group 300, and a main valve group 400. The oil tank 100 is filled with hydraulic oil to provide hydraulic power. The first pump group 200 is connected to the oil tank 100. The second pump group 300 is connected to the oil tank 100 and runs parallel to the first pump group 200. The main valve group 400 connects the first pump group 200 and the second pump group 300. The first pump group 200 and the second pump group 300 supply oil to the actuators of the tracked aerial work platform through the main valve group 400. Simultaneously, the first pump group 200 and the second pump group 300 supply oil to the walking mechanism of the tracked aerial work platform through the main valve group 400, and the first pump group 200 and the second pump group 300 respectively achieve independent flow control of the walking mechanism of the tracked aerial work platform. The first pump group 200 and the second pump group 300 both consist of permanent magnet motors and pumps. The pump flow rate is adjusted by setting the speed of the permanent magnet motors. The use of permanent magnet motors, with their permanent magnet rotors and thin silicon steel stators, results in low heat generation and low noise. These two power units, the first pump group 200 and the second pump group 300, provide power to each of the left and right wheels of the tracked aerial work platform during movement. The speed of the permanent magnet motors is set to compensate for any errors in the flow rates of the two pumps, ensuring better synchronous forward and backward movement of the left and right wheels. Simultaneously, the first pump group 200 and the second pump group 300, in conjunction with the main valve group 400, supply oil to the actuator 700 to perform lifting, lowering, rotation, and swinging actions on the tracked aerial work platform. The operating speed of the lifting, rotation, and swinging actuators is set by the speed of the permanent magnet motors, changing the pump flow rate and achieving stepless speed regulation.

[0025] Reference Figure 1As shown, the main valve group 400 includes a first check valve 1, a second check valve 2, a first solenoid directional valve 3, a second solenoid directional valve 4, a third solenoid directional valve 5, and a solenoid valve 6. The first pump group 200 is connected to the first traveling mechanism 500 through the first check valve 1, and the second pump group 300 is connected to the second traveling mechanism 600 through the second check valve 2. The first solenoid directional valve 3 is located on the return oil line between the first traveling mechanism 500 and the oil tank 100, the second solenoid directional valve 4 is located on the return oil line between the second traveling mechanism 600 and the oil tank 100, the third solenoid directional valve 5 is located on the oil supply line between the first pump group 200, the second pump group 300, and the actuator 700, and the solenoid valve 6 is located between the oil supply line of the first pump group 200 and the second pump group 300 to realize that the first pump group 200 and the second pump group 300 alternately supply oil to the actuator 700. The solenoid valve 6 is an emergency solenoid valve (with manual operation). A solenoid valve 6 is connected in series between the oil supply lines of the first pump group 200 and the second pump group 300. When a specific device in one of the groups, such as a permanent magnet motor or pump, malfunctions, the solenoid valve 6 is energized, enabling the operation of lifting, rotating, and swinging actuators. In this case, the two groups of motors and pumps act as emergency backups for each other, eliminating the need for additional emergency pumps.

[0026] Specifically, the first solenoid directional valve 3, the second solenoid directional valve 4, and the third solenoid directional valve 5 are all three-position four-way solenoid directional valves, and the solenoid valve 6 is a two-position two-way solenoid directional valve. The solenoid directional valve is a switching element between the hydraulic control system and the electrical control system. It utilizes the attraction force of electromagnets at both ends to realize the movement of the valve core, thereby changing the on / off state of the oil circuit and thus realizing the switching of the actuator.

[0027] The main valve assembly 400 also includes a pressure reducing valve 7 and a fifth solenoid directional valve 8. The first traveling mechanism 500 and the second traveling mechanism 600 are both connected to the fifth solenoid directional valve 8. The pressure reducing valve 7 is connected between the fifth solenoid directional valve 8 and the oil supply line of the actuator 700, and the fifth solenoid directional valve 8 is also connected to the oil return line of the oil tank 100. The pressure reducing valve 7 and the fifth solenoid directional valve 8 are configured to perform pressure reduction control.

[0028] Specifically, the fifth solenoid directional valve 8 is a three-position three-way solenoid directional valve.

[0029] The return oil line of the oil tank 100 is connected to a return oil filter 9. The inlet oil lines from the oil tank 100 to the first pump group 200 and the second pump group 300 are both connected to inlet oil filters 10.

[0030] A sixth solenoid directional valve 11 and a first relief valve 12 are installed between the oil inlet and return lines of the first pump set 200. The sixth solenoid directional valve 11 can directly guide the oil input from the first pump set 200 back to the return line. When the sixth solenoid directional valve 11 is open, it allows the first traveling mechanism 500 driven by the first pump set 200 to idle. At the same time, the sixth solenoid directional valve 11 and the first relief valve 12 serve to protect the oil pump and relieve load.

[0031] Similarly, a seventh solenoid directional valve 13 and a second relief valve 14 are provided between the oil inlet and return lines of the second pump set 300. The seventh solenoid directional valve 13, when open, allows the second traveling mechanism 600 driven by the second pump set 300 to idle. Simultaneously, the seventh solenoid directional valve 13 and the second relief valve 14 protect the oil pump and relieve load.

[0032] Obviously, the above embodiments are merely illustrative examples for clear explanation and are not intended to limit the implementation. Those skilled in the art will recognize that other variations or modifications can be made based on the above description. It is neither necessary nor possible to exhaustively list all possible implementations here. However, obvious variations or modifications derived therefrom are still within the protection scope of this invention.

Claims

1. A hydraulic system for a tracked aerial work platform, characterized in that, include: The oil tank contains hydraulic oil that provides hydraulic power; The first pump unit is connected to the oil tank; The second pump set is connected to the oil tank and runs parallel to the first pump set; The main valve group connects the first pump group and the second pump group. The first pump group and the second pump group supply oil to the actuator of the tracked aerial work platform through the main valve group. At the same time, the first pump group and the second pump group supply oil to the walking mechanism of the tracked aerial work platform through the main valve group respectively. The first pump group and the second pump group respectively realize the independent flow control of the walking mechanism of the tracked aerial work platform. The main valve group includes a first check valve, a second check valve, a first solenoid directional valve, a second solenoid directional valve, a third solenoid directional valve, and a solenoid valve. The first pump group is connected to the first traveling mechanism through the first check valve, and the second pump group is connected to the second traveling mechanism through the second check valve. The first solenoid directional valve is located on the return oil line between the first traveling mechanism and the oil tank, and the second solenoid directional valve is located on the return oil line between the second traveling mechanism and the oil tank. The third solenoid directional valve is located on the oil supply line between the first and second pump groups and the actuator. The solenoid valve is located between the oil supply lines of the first and second pump groups to enable the first and second pump groups to alternately supply oil to the actuator.

2. The hydraulic system of a tracked aerial work platform according to claim 1, characterized in that: The tracked aerial work platform includes a first traveling mechanism, a second traveling mechanism, and an execution mechanism.

3. The hydraulic system of the tracked aerial work platform according to claim 1, characterized in that: The first, second, and third electromagnetic directional valves are all three-position four-way electromagnetic directional valves.

4. The hydraulic system of the tracked aerial work platform according to claim 3, characterized in that: The solenoid valve is a two-position two-way solenoid directional valve.

5. The hydraulic system of the tracked aerial work platform according to claim 1, characterized in that: The main valve group also includes a pressure reducing valve and a fifth solenoid directional valve. The first traveling mechanism and the second traveling mechanism are both connected to the fifth solenoid directional valve. The pressure reducing valve is connected between the fifth solenoid directional valve and the oil supply line of the actuator, and the fifth solenoid directional valve is connected to the oil return line of the oil tank.

6. The hydraulic system of the tracked aerial work platform according to claim 5, characterized in that: The fifth solenoid directional valve is a three-position three-way solenoid directional valve.

7. The hydraulic system of the tracked aerial work platform according to claim 1, characterized in that: The oil tank's return line is connected to a return oil filter.

8. The hydraulic system of the tracked aerial work platform according to claim 1, characterized in that: Oil inlet filters are connected to the oil inlet pipes from the oil tank to the first and second pump groups.

9. The hydraulic system of the tracked aerial work platform according to claim 1, characterized in that: The first pump set is provided with a sixth solenoid directional valve and a first relief valve between the oil inlet pipe and the oil return pipe, and the second pump set is provided with a seventh solenoid directional valve and a second relief valve between the oil inlet pipe and the oil return pipe.

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