Aerial vehicle pit protection structure and hydraulic control system thereof

Abstract

The invention discloses a high-altitude vehicle pit protection structure and a hydraulic control system thereof. A pit control valve, an auxiliary hydraulic pipeline and a connector are omitted, a multi-way valve is additionally provided with a link for independently controlling opening and closing of a pit to optimize amplitude variation, the phenomenon of amplitude variation stop is avoided when a pit baffle is opened, control logic and a hydraulic control mode are simplified, redundant pipelines are omitted, cost is reduced, space is saved, and the system is suitable for large-scale popularization and application. The operation experience is improved, and the working efficiency is improved.

Description

Technical Field

[0001] This invention relates to the field of engineering machinery technology, specifically to a protective structure for pits in aerial work platforms and its hydraulic control system. Background Technology

[0002] The pit stop guard on an aerial work platform is a device to ensure the safety of operators. Aerial work platforms equipped with pit stop guards have two working states: First, the retracted state, where the boom is fully retracted and raised to a working range of 5° with the horizontal. In this state, the pit stop guard is not open, and the travel speed is high. Second, the raised state, where the boom is raised from 5° to a maximum working range of 70°. In this state, the pit stop guard is open, the travel speed is reduced, and safety is ensured during operation.

[0003] The shortcomings of existing technology: Currently, during lifting operations, when the luffing angle exceeds 5° of the horizontal angle, the pit baffle opens, causing the luffing speed to drop sharply and stop. Once the baffle is fully open, the luffing speed returns to normal. Analysis reveals that because the pit load is much lower than the load during luffing, the parallel connection of the pit control valve and the multi-way valve causes a large amount of hydraulic oil to flow to the low-load side, resulting in the luffing stopping when the pit baffle opens during the luffing process. This significantly impacts the operator experience, complicates the control method and piping connections, increases operating costs, and reduces work efficiency. Summary of the Invention

[0004] The purpose of this invention is to provide a protective structure for pits in aerial work platforms and its hydraulic control system, so as to solve the problems mentioned in the background art.

[0005] To achieve the above objectives, the present invention provides the following technical solution: a pit protection structure for aerial work platforms, comprising a chassis, an operator's cab, and a telescopic boom, wherein the operator's cab is disposed on the chassis, the chassis is provided with a pit baffle for ensuring personnel driving safety, and the operator's cab is provided with a telescopic operating assembly for lifting connected to the telescopic boom, the telescopic operating assembly comprising: A pull rod is provided in the operating room and connected to the telescopic arm via a connector. The pull rod is equipped with a lower angle sensor for detecting angle changes. A lower luffing cylinder, which is connected to the lower pull rod and controls the lifting of the lower pull rod; Upper luffing cylinder, which is connected to the telescopic boom and controls the raising and lowering of the telescopic boom; An upper angle sensor is disposed on the telescopic arm and connected to the upper luffing cylinder, and the upper angle sensor is used to detect angle changes.

[0006] The present invention also provides a hydraulic system for protecting potholes on aerial work platforms. The hydraulic system includes a control component for controlling the opening and closing of the pothole baffle and a power source component for providing a power source. The control component includes: A lower luffing cylinder control valve is provided, which connects to and controls the operation of the lower luffing cylinder. The C1 port of the lower luffing cylinder control valve is connected to the rodless chamber of the lower luffing cylinder, and the C2 port of the lower luffing cylinder control valve is connected to the rod chamber of the lower luffing cylinder. The upper luffing cylinder control valve is connected to and controls the operation of the upper luffing cylinder. The C1 port of the upper luffing cylinder control valve is connected to the rodless chamber of the upper luffing cylinder, and the C2 port of the upper luffing cylinder control valve is connected to the rod chamber of the upper luffing cylinder. A multi-way valve is used to change the direction of hydraulic oil. The multi-way valve A1 port is connected to the lower luffing cylinder control valve V1 port, the multi-way valve B1 port is connected to the lower luffing cylinder control valve V2 port, the multi-way valve A2 port is connected to the upper luffing cylinder control valve V1 port, and the multi-way valve B2 port is connected to the upper luffing cylinder control valve V2 port. Two pit-filling cylinders are provided, each connected to the chassis and the pit-filling baffle. The two cylinders control the opening or retraction of the pit-filling baffle.

[0007] Preferably, the power source assembly includes: Oil tank, the oil tank being used to store hydraulic oil; A gear pump, the oil inlet of which is connected to the oil tank, is used to supply hydraulic oil; A drive motor is provided, which is connected to the gear pump and controls the operation of the gear pump.

[0008] Preferably, the multi-way valve is connected to two hydraulic locks, with port A3 of the multi-way valve connected to ports V6 of the two hydraulic locks, and port B3 of the multi-way valve connected to ports V5 of the two hydraulic locks.

[0009] Preferably, the two hydraulic lock C6 ports are respectively connected to the rodless chambers of the two pit cylinders.

[0010] Preferably, the gear pump is connected to the P port of the multi-way valve.

[0011] Preferably, the T port and TS port of the multi-way valve are connected to the oil tank.

[0012] Compared with the prior art, the beneficial effects of the present invention are: This invention discloses a pothole protection structure for aerial work platforms and its hydraulic control system. By eliminating the pothole control valve and its associated hydraulic lines and joints, and by adding a separate control to the multi-way valve to control the opening and closing of the pothole, the invention optimizes the luffing and prevents luffing from stopping when opening the pothole baffle. This simplifies the control logic and hydraulic control method, eliminates redundant lines, reduces costs, saves space, improves the user experience, and increases work efficiency. Attached Figure Description

[0013] Figure 1 This is a schematic diagram of the aerial work platform pit protection structure of the present invention; Figure 2 This is a schematic diagram illustrating the opening principle of the pit baffle of the present invention; In the diagram: 1. Chassis; 2. Operator's cab; 3. Telescopic boom; 4. Pit baffle; 5. Lower lever; 6. Lower angle sensor; 7. Lower luffing cylinder; 8. Upper luffing cylinder; 9. Upper angle sensor; 10. Lower luffing cylinder control valve; 11. Upper luffing cylinder control valve; 12. Multi-way valve; 13. Two pit cylinders; 14. Oil tank; 15. Gear pump; 16. Drive motor; 17. Two hydraulic locks. Detailed Implementation

[0014] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0015] In the description of this invention, it should be understood that the terms "center," "longitudinal," "lateral," "length," "width," "thickness," "upper," "lower," "top," "bottom," "inner," "outer," "clockwise," and "counterclockwise," etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. They are only for the convenience of describing this invention and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limitations on this invention.

[0016] In the description of this patent, it should be noted that, unless otherwise explicitly specified and limited, the terms "installation," "connection," and "setting" should be interpreted broadly. For example, they can refer to a fixed connection or setting, a detachable connection or setting, or an integrated connection or setting. Those skilled in the art can understand the specific meaning of the above terms in this patent according to the specific circumstances.

[0017] Furthermore, the terms "first" and "second" are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of technical features indicated. Thus, a feature defined as "first" or "second" may explicitly or implicitly include one or more of that feature. In the description of this invention, "a number" means two or more, unless otherwise explicitly specified.

[0018] Example Please see Figure 1 As shown, the present invention provides a technical solution for a pit protection structure for aerial work platforms: It includes a chassis 1, an operator's cab 2, and a telescopic boom 3. The operator's cab 2 is located on the chassis 1. The chassis 1 is equipped with a pit baffle 4 to ensure the safety of personnel during travel. The operator's cab 2 is equipped with a telescopic operating assembly for lifting, which connects to the telescopic boom 3. The telescopic operating assembly includes a pull rod 5, a lower luffing cylinder 7, a lower angle sensor 6, an upper luffing cylinder 8, and an upper angle sensor 9. The pull rod 5 is located in the operator's cab 2 and connected to the telescopic boom 3 via a connector. 5. A lower angle sensor 6 is installed to detect angle changes. The lower luffing cylinder 7 is connected to the lower pull rod 5 and controls the lifting of the lower pull rod 5. The upper luffing cylinder 8 is connected to the telescopic boom 3 and controls the lifting of the telescopic boom 3. The upper angle sensor 9 is set on the telescopic boom 3 and connected to the upper luffing cylinder 8. The upper angle sensor 9 is used to detect angle changes. When the aerial work platform is in the fully retracted state, the lower luffing cylinder 7 or the upper luffing cylinder 8 extends, causing the lower pull rod 5 or the telescopic boom 3 to change angle. The angle is detected by the lower angle sensor 6 and the upper angle sensor 9.

[0019] This invention also provides a hydraulic system for protecting aerial work platforms from potholes, such as... Figure 2As shown, the hydraulic system includes a control component that controls the opening and closing of the pit baffle 4 and a power source component that provides the power source. The control component includes a lower luffing cylinder control valve 10, an upper luffing cylinder control valve 11, a multi-way valve 12, and two pit cylinders 13. The lower luffing cylinder control valve 10 is connected to and controls the operation of the lower luffing cylinder 7. Port C1 of the lower luffing cylinder control valve 10 is connected to the rodless chamber of the lower luffing cylinder 7, and port C2 of the lower luffing cylinder control valve 10 is connected to the rod chamber of the lower luffing cylinder 7. The upper luffing cylinder control valve 11 is connected to and controls the operation of the upper luffing cylinder 8. Port C1 of the upper luffing cylinder control valve 11 is connected to the upper luffing cylinder 8. The rodless chamber of the luffing cylinder 8 is connected to the rod chamber of the upper luffing cylinder 8 via port C2 of the upper luffing cylinder control valve 11. The multi-way valve 12 is used to change the direction of the hydraulic oil. Port A1 of the multi-way valve 12 is connected to port V1 of the lower luffing cylinder control valve 10, port B1 of the multi-way valve 12 is connected to port V2 of the lower luffing cylinder control valve 10, port A2 of the multi-way valve 12 is connected to port V1 of the upper luffing cylinder control valve 11, and port B2 of the multi-way valve 12 is connected to port V2 of the upper luffing cylinder control valve 11. Both pitting cylinders 13 are connected to the chassis 1 and the pitting baffle 4. The two pitting cylinders 13 control the opening or retraction of the pitting baffle 4. The multi-way valve 12 is connected to two hydraulic locks 17. The A3 port of the multi-way valve 12 is connected to the V6 port of the two hydraulic locks 17, the B3 port of the multi-way valve 12 is connected to the V5 port of the two hydraulic locks 17, and the C6 ports of the two hydraulic locks 17 are respectively connected to the rodless chambers of the two pit cylinders 13.

[0020] The power source assembly includes an oil tank 14, a gear pump 15, and a drive motor 16. The oil tank 14 is used to store hydraulic oil. The T port and TS port of the multi-way valve 12 are connected to the oil tank 14. The oil suction port of the gear pump 15 is connected to the oil tank 14. The gear pump 15 is connected to the P port of the multi-way valve 12. The gear pump 15 is used to supply hydraulic oil. The drive motor 16 is connected to the gear pump 15 and controls the operation of the gear pump 15.

[0021] When in use, the pit baffle 4 opens as follows: When the luffing cylinder is lowered, the drive motor 16 drives the gear pump 15 to draw oil from the oil tank 14. The hydraulic oil enters the P port PV1 of the multi-way valve 12 and is energized, causing the hydraulic oil flowing in from the P port of the multi-way valve 12 to flow out from the A1 port of the multi-way valve 12. The hydraulic oil enters the V1 port of the lower luffing cylinder control valve 10, flows out through the C1 port of the lower luffing cylinder control valve 10, and enters the rodless chamber of the lower luffing cylinder 7. The hydraulic oil in the rod chamber of the lower luffing cylinder 7 returns to the oil tank 14 after passing through the C2 port and V2 port of the lower luffing cylinder control valve 10, the B1 port and T port of the multi-way valve 12. At this time, the lower luffing cylinder 7 extends, causing the lower lever 5 to change angle. When the angle of the lower lever 5 is detected to be greater than 5° of the horizontal angle, at the same time that the multi-way valve 12PV1 is energized, PV5 is energized, causing hydraulic oil to flow out from port A3 of the multi-way valve 12 into port V6 of the two hydraulic locks 17, and then into the rodless chamber of the two pit cylinders 13 through port C6. The hydraulic oil in the rod chamber of the two pit cylinders 13 returns to the oil tank 14 after passing through port C5 and port V5 of the two hydraulic locks 17, port B3 and port T of the multi-way valve 12. At this time, the two pit cylinders 13 extend, causing the pit baffle 4 to open.

[0022] During the upward luffing operation, the drive motor 16 drives the gear pump 15 to draw oil from the oil tank 14. The hydraulic oil enters the P port PV3 of the multi-way valve 12, which is energized, causing the hydraulic oil flowing in from the P port of the multi-way valve 12 to flow out from the A2 port of the multi-way valve 12. The hydraulic oil enters the V1 port of the upper luffing cylinder control valve 11, flows out through the C1 port of the upper luffing cylinder control valve 11, and enters the rodless chamber of the upper luffing cylinder 8. The hydraulic oil in the rod chamber of the upper luffing cylinder 8 returns to the oil tank 14 after passing through the C2 port and V2 port of the upper luffing cylinder control valve 11, the B2 port and T port of the multi-way valve 12. At this time, the upper luffing cylinder 8 extends, causing the upper pull rod angle to change. When the upper pull rod angle is detected to be greater than 5° of the horizontal angle, at the same time that the multi-way valve 12PV3 is energized, PV5 is energized, causing hydraulic oil to flow out from the A3 port of the multi-way valve 12 into the V6 port of the two hydraulic locks 17, and then into the rodless chamber of the two pit cylinders 13 through the C6 port. The hydraulic oil in the rod chamber of the two pit cylinders 13 returns to the oil tank 14 after passing through the C5 port and V5 port of the two hydraulic locks 17, the B3 port and T port of the multi-way valve 12. At this time, the two pit cylinders 13 extend, causing the pit baffle 4 to open.

[0023] The added multi-way valve 12 also includes a pressure compensator. The inlet of the pressure compensator is connected to the P port of the multi-way valve 12, and the outlet is connected in parallel with the load and LS port. During the luffing and lifting operation, the pit baffle 4 is opened, which is a combined action for the multi-way valve 12. During this combined action, LS only detects the highest pressure. The inlet pressure of each compensator is the same, and the pressure at the P port before each valve core is the same, ensuring that the pressure difference ΔP before and after each valve core is the same. According to the flow calculation formula Q=K... A ΔP, where K is the flow coefficient (a constant), A is the valve core opening area, and ΔP is the pressure difference across the valve core, shows that the flow rate through the valve core is determined only by the valve core opening area. By changing the current of the multi-way valves 12PV1-PV4, the valve core opening area can be changed, thereby controlling the flow rate and the speed of each action, regardless of the load pressure. Therefore, opening the pit baffle 4 while performing luffing will not cause the luffing to stop; when performing compound actions, the speed of the drive motor 16 can be appropriately increased by the program so that the speed of each action is not affected during compound actions.

[0024] The foregoing has shown and described the basic principles, main features, and advantages of the present invention. Those skilled in the art should understand that the present invention is not limited to the above embodiments. The embodiments and descriptions in the specification are merely preferred examples and are not intended to limit the invention. Various changes and modifications can be made to the invention without departing from its spirit and scope, and all such changes and modifications fall within the scope of the present invention as claimed. The scope of protection of the present invention is defined by the appended claims and their equivalents.

Claims

1. A pit protection structure for aerial work platforms, comprising a chassis (1), an operating cab (2), and a telescopic boom (3), characterized in that: The operating room (2) is located on the chassis (1), the chassis (1) is provided with a pit baffle (4) for ensuring the safety of personnel driving, and the operating room (2) is provided with a telescopic operating assembly for lifting connected to the telescopic arm (3). The telescopic operating assembly includes: A pull rod (5) is provided in the operating room (2) and connected to the telescopic arm (3) by means of a connecting piece. The pull rod (5) is equipped with a lower angle sensor (6) for detecting angle changes. The lower luffing cylinder (7) is connected to the lower pull rod (5) and controls the lifting of the lower pull rod (5); Upper luffing cylinder (8), which is connected to the telescopic boom (3) and controls the lifting and lowering of the telescopic boom (3); Upper angle sensor (9) is installed on the telescopic arm (3) and connected to the upper luffing cylinder (8). The upper angle sensor (9) is used to detect angle changes.

2. The hydraulic system for protecting aerial work platforms from potholes according to claim 1, characterized in that: The hydraulic system includes a control component for controlling the opening and closing of the pit baffle (4) and a power source component for providing a power source. The control component includes: The lower luffing cylinder control valve (10) is connected to and controls the operation of the lower luffing cylinder (7). The C1 port of the lower luffing cylinder control valve (10) is connected to the rodless chamber of the lower luffing cylinder (7), and the C2 port of the lower luffing cylinder control valve (10) is connected to the rod chamber of the lower luffing cylinder (7). Upper luffing cylinder control valve (11), the upper luffing cylinder control valve (11) is connected to and controls the operation of the upper luffing cylinder (8), the C1 port of the upper luffing cylinder control valve (11) is connected to the rodless chamber of the upper luffing cylinder (8), and the C2 port of the upper luffing cylinder control valve (11) is connected to the rod chamber of the upper luffing cylinder (8); A multi-way valve (12) is used to change the direction of hydraulic oil. The A1 port of the multi-way valve (12) is connected to the V1 port of the lower luffing cylinder control valve (10), the B1 port of the multi-way valve (12) is connected to the V2 port of the lower luffing cylinder control valve (10), the A2 port of the multi-way valve (12) is connected to the V1 port of the upper luffing cylinder control valve (11), and the B2 port of the multi-way valve (12) is connected to the V2 port of the upper luffing cylinder control valve (11). Two pit cylinders (13) are connected to the chassis (1) and the pit baffle (4). The two pit cylinders (13) control the pit baffle (4) to open or retract.

3. The hydraulic system for protecting aerial work platforms from potholes according to claim 2, characterized in that: The power source assembly includes: Oil tank (14), the oil tank (14) is used to store hydraulic oil; A gear pump (15) with its suction port connected to the oil tank (14) is used to supply hydraulic oil. A drive motor (16) is connected to the gear pump (15) and controls the operation of the gear pump (15).

4. The hydraulic system for protecting aerial work platforms from potholes according to claim 2, characterized in that: The multi-way valve (12) is connected to two hydraulic locks (17). The A3 port of the multi-way valve (12) is connected to the V6 port of the two hydraulic locks (17), and the B3 port of the multi-way valve (12) is connected to the V5 port of the two hydraulic locks (17).

5. The hydraulic system for protecting aerial work platforms from potholes according to claim 4, characterized in that: The two hydraulic locks (17) C6 ports are respectively connected to the rodless chambers of the two pit cylinders (13).

6. The hydraulic system for protecting aerial work platforms from potholes according to claim 3, characterized in that: The gear pump (15) is connected to the P port of the multi-way valve (12).

7. The hydraulic system for protecting aerial work platforms from potholes according to claim 3, characterized in that: The T port and TS port of the multi-way valve (12) are connected to the oil tank (14).

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