Aerial work platform limiting warning device and prompt control system thereof

Abstract

The application discloses a high-altitude operation vehicle limiting warning device and a prompt control system thereof, relates to the technical field of high-altitude operation vehicles, and comprises an elevator, two guardrails, fixing sleeves arranged on one side of the guardrails, supporting rods arranged in the fixing sleeves, buffer sleeves arranged on the outer sides of the top ends of the supporting rods, communication pipes fixedly connected to the top ends of the buffer sleeves, warning rods inserted into the communication pipes, limiting sleeves fixedly connected to one side of the buffer sleeves, guide plates fixedly connected to one side of the limiting sleeves, connecting plates fixedly connected to the two sides of the limiting sleeves, first buffer plates and second buffer plates fixedly connected to one side of the two connecting plates, and first rotating plates arranged in the first buffer plates. The high-altitude operation vehicle limiting warning device and the prompt control system thereof realize double limiting responses of mechanical triggering and photoelectric detection, are simple in structure, and are reliable in triggering.

Description

Technical Field

[0001] This invention relates to the field of aerial work platform technology, specifically to an aerial work platform limit warning device and its prompting control system. Background Technology

[0002] Aerial work platforms are versatile specialized equipment for working at heights. They are categorized into: scissor lift aerial work platforms, telescopic boom aerial work platforms, aluminum alloy aerial work platforms, and articulated boom aerial work platforms. Aerial work platforms offer safety and stability, fast travel speed, smooth lifting, and an attractive appearance, making them ideal for high-altitude maintenance and repair work.

[0003] The prior art utility model patent with publication number CN220317331U discloses a safety hydraulic lifting vehicle with a limit device, including a scissor lift and a vehicle body. The scissor lift is located directly above the vehicle body and is mounted on the surface of the vehicle body. A load-bearing platform is mounted on the upper surface of the scissor lift. The vehicle body intelligently controls the lifting and lowering of the load-bearing platform through the scissor lift. A radar sensor is integrated inside the vehicle body. The system controller for the radar sensor integration is an LPC2214 microcontroller. The system hardware introduces a distance measuring sensor integration to measure the distance between the upper safety guardrail and the top object or wall, and the distance from the ground. When the set safety distance is reached, an alarm is issued to achieve the limit function. The aforementioned patent mainly uses radar sensors to monitor the lifting height of the lifting platform, realizing the limit alarm function of the lifting height. However, in actual use, it can only monitor the lifting height in a single dimension. When the lifting platform encounters an obstacle, it lacks a direct mechanical triggering structure and anti-interference judgment mechanism. It is easy for the sensor to be falsely triggered due to vibration during normal operation of the equipment, which affects the work efficiency and safety.

[0004] The existing limit warning devices for aerial work platforms mostly rely solely on electronic sensors for height monitoring, lacking a dual limit response mechanism that combines mechanical linkage and electrical detection. Furthermore, they are insufficient in resisting vibration interference, which can easily lead to false alarms or accidental shutdowns, thus adversely affecting the reliability of the limit warning devices and the operational stability of the aerial work platform. Summary of the Invention

[0005] The purpose of this invention is to provide a limit warning device for aerial work platforms and its warning control system to solve the problems mentioned in the background art.

[0006] To achieve the above objectives, the present invention provides the following technical solution: a limit warning device and its warning control system for an aerial work platform, comprising a lift, a lifting platform installed on the top of the lift, an audible and visual alarm installed on one side of the lifting platform, guardrails installed on both sides of the top of the lifting platform, a fixing sleeve provided on one side of each guardrail, a support rod provided inside the fixing sleeve, a buffer sleeve fitted on the outer side of the top of the support rod, a connecting pipe fixedly connected to the top of the buffer sleeve, a warning rod inserted into the connecting pipe, a limit sleeve fixedly connected to one side of the buffer sleeve, and a limit sleeve fixedly connected to one side of the limit sleeve. The device is equipped with a guide plate, and a toothed plate is slidably connected inside the guide plate. A guide gear is provided at the bottom of the device's interior. A rotating shaft is fixedly connected inside the guide gear. The two ends of the rotating shaft pass through the two side walls of the device and are rotatably connected to the device. A connecting plate is fixedly connected to both sides of the device. A first buffer plate and a second buffer plate are fixedly connected to one side of each of the two connecting plates. A first rotating plate is provided inside the first buffer plate. A first through hole is opened inside both ends of the first rotating plate. A second rotating plate is provided inside the second buffer plate. A second through hole is opened inside both ends of the second rotating plate.

[0007] Preferably, both the first and second buffer plates are filled with buffer solution. The two ends of the rotating shaft pass through the first and second buffer plates respectively and are rotatably connected to them. One-way bearings are fixedly connected to the outer sides of both ends of the rotating shaft. The outer sides of the two one-way bearings are fixedly connected to the first and second rotating plates respectively. The inner and outer rings of the two one-way bearings have opposite limiting directions, so that when the guide gear rotates in the forward direction, it drives the rotating shaft to rotate in the forward direction, thereby driving the first rotating plate to rotate. At this time, the second rotating plate rotates relative to the rotating shaft. When the guide gear rotates in the reverse direction, it drives the rotating shaft and the second rotating plate to rotate in the opposite direction, and causes the first rotating plate to rotate relative to the rotating shaft, so that the toothed plate forms different damping magnitudes when moving up and down.

[0008] Preferably, both sides of the support rod are integrally formed with limit plates, and both sides of the buffer sleeve are provided with limit grooves. The two limit plates are slidably connected to the two limit grooves and adapted to the two limit grooves, thereby limiting the support rod and improving the stability of the support rod.

[0009] Preferably, a through groove is provided on one side of the buffer sleeve, one side of the guide gear is disposed inside the through groove, a toothed groove is provided on one side of the top end of the support rod, one side of the guide gear is meshed with the toothed groove, and the toothed plate is meshed with the other side of the guide gear, so that the toothed plate pushes the guide gear and the rotating shaft to rotate when it moves.

[0010] Preferably, an upper support plate is fixedly connected to one side of the top of the toothed plate, a vertical rod is fixedly connected to the bottom of the upper support plate, and a detection head is fixedly connected to the bottom of the vertical rod, so that the toothed plate moves when it moves, and the upper support plate moves when it moves, which in turn moves the vertical rod and the detection head.

[0011] Preferably, a lower support plate is fixedly connected to the bottom of the inner part of the limiting sleeve, a laser sensor is fixedly connected to the top of the lower support plate, a support plate is fixedly connected to the inner part of the limiting sleeve, a circular hole is opened inside the support plate, the detection head corresponds to the circular hole and the laser sensor, a spring is fixedly connected to the top of the support plate, and the top of the spring is fixedly connected to the bottom of the upper support plate so that the spring supports the upper support plate.

[0012] Preferably, the upper and lower ends of the fixed sleeve are fixedly connected to the support sleeve, and the two support sleeves are provided with sliding grooves on both sides. The two limiting plates are slidably connected to the two sliding grooves and adapted to the two sliding grooves to limit the position of the support rod.

[0013] Preferably, a clamp is fixedly connected to one side of the fixing sleeve, the clamp is fitted onto the outside of the guardrail, and the two sides of the clamp are fixed by bolts to facilitate the fixing and support of the clamp.

[0014] Preferably, a threaded rod is threadedly connected to one side of the fixed sleeve. A clamping plate is rotatably connected to one end of the threaded rod inside the fixed sleeve. Friction plates are fixedly connected to both ends of the clamping plate. The clamping plate is in contact with the outer side of the support rod. The two friction plates are respectively in contact with two limiting plates. A handle is fixedly connected to one end of the threaded rod on the outer side of the fixed sleeve. Rotating the handle causes the threaded rod to rotate, moving the threaded rod inside the fixed sleeve. This causes the fixed sleeve to move inside the clamping plate, which in turn causes the clamping plate to move the friction plates. The friction plates and clamping plate clamp and fix the support rod, facilitating the adjustment of the support rod's height.

[0015] A limit indicator control system for aerial work platforms includes: The laser sensor detects changes in the position of the detection head in real time and outputs a detection signal; When the position change of the detection head does not exceed the preset threshold, it is determined to be normal vibration and no shutdown is triggered; When the position change of the detection head exceeds a preset threshold and continues for a set time, it is determined to be a real limit trigger event; After the controller determines that a real limit switch trigger event has occurred, it cuts off the elevator's upward control circuit and triggers the audible and visual alarm. After the obstacle is removed, the spring pushes the detection head to reset, the laser sensor signal returns to normal, the controller deactivates the shutdown alarm, and the elevator is allowed to rise again.

[0016] Compared with the prior art, the beneficial effects of the present invention are: 1. This application sets up a linkage structure between the warning rod and the connecting pipe. When the warning rod touches the obstacle above, it can drive the buffer sleeve to slide down the support rod, and then drive the guide gear to rotate through the tooth groove, so that the tooth plate drives the detection head to descend and be identified by the laser sensor, thereby realizing a dual limit response of mechanical triggering and photoelectric detection. The structure is simple and the triggering is reliable.

[0017] 2. This application provides a first buffer plate and a second buffer plate on both sides of the limiting sleeve, respectively. Each buffer plate is filled with buffer solution and, together with a one-way bearing, a first rotating plate, and a second rotating plate, forms a direction-dependent damping structure. When the toothed plate descends, the rotation of the first rotating plate generates significant damping, which, in conjunction with the spring, effectively suppresses minor vibrations that could trigger the system during normal operation. When the plate rises and resets, the rotation of the second rotating plate generates less damping, ensuring a smooth reset of the buffer sleeve and significantly improving the system's anti-interference capability and stability.

[0018] 3. This application uses a laser sensor to detect changes in the position of the detection head in real time, and sets a threshold for position change and a duration judgment logic. Only when the threshold is exceeded and continues for a certain period of time is it determined to be a real limit event, at which point the controller cuts off the lifting control circuit of the elevator and triggers an audible and visual alarm. This control system effectively distinguishes between normal vibration and real collisions, avoids frequent false shutdowns, and ensures timely response when danger occurs, thus improving the safety of high-altitude operations.

[0019] 4. The support rod of this application is installed on the guardrail by a fixing sleeve. The fixing sleeve has a clamp and bolt fixing structure on one side, which facilitates quick disassembly and installation and position adjustment. At the same time, the support rod is clamped and locked by a threaded rod, a clamping plate and a friction plate, and is guided by a limit plate and a sliding groove. It is easy to adjust and firmly fixed, adapting to different vehicle models and working height requirements, and has low installation and maintenance costs. Attached Figure Description

[0020] Figure 1 This is a schematic diagram of the overall structure of the present invention; Figure 2 This is a schematic diagram showing the installation state of the present invention with the guardrail; Figure 3 This is a schematic diagram of the support rod of the present invention; Figure 4 This is a schematic diagram of the connecting pipe of the present invention; Figure 5 This is a schematic diagram of the structure of the warning bar of the present invention; Figure 6 This is a schematic diagram of the toothed plate of the present invention; Figure 7 This is a schematic diagram of the structure of the guide plate of the present invention; Figure 8 This is a schematic diagram of the detection head of the present invention; Figure 9 This is a schematic diagram of the connecting plate of the present invention; Figure 10 This is a schematic diagram of the structure of the rotating plate of the present invention; Figure 11 This is a schematic diagram of the structure of the first buffer plate of the present invention; Figure 12 This is a schematic diagram of the structure of the fixing sleeve of the present invention; Figure 13 This is a schematic diagram of the structure of the clamping plate of the present invention; Figure 14 This is a schematic diagram of the jacket structure of the present invention; Figure 15 This is a schematic diagram of the control system of the present invention.

[0021] The following are the labeling elements in the diagram: 1. Elevator; 2. Lifting platform; 3. Guardrail; 4. Fixing sleeve; 5. Support rod; 6. Buffer sleeve; 7. Connecting pipe; 8. Warning pole; 9. Limiting sleeve; 10. Gear plate; 11. Rotating shaft; 12. Guide gear; 13. Gear groove; 14. Through groove; 15. Guide plate; 16. Connecting plate; 17. First buffer plate; 18. Second buffer plate; 19. First rotating plate; 20. Second rotating plate. 21. First through hole; 22. Second through hole; 23. One-way bearing; 24. Lower support plate; 25. Laser sensor; 26. Support plate; 27. Round hole; 28. Upper support plate; 29. ​​Spring; 30. Vertical rod; 31. Detection head; 32. Limiting groove; 33. Limiting plate; 34. Threaded rod; 35. Clamping plate; 36. Friction plate; 37. Handle; 38. Jacket; 39. Support sleeve; 40. Slide groove. Detailed Implementation

[0022] 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.

[0023] Example 1: As Figures 1-14As shown, this invention provides a technical solution for a limit warning device for an aerial work platform, including a lift 1, a lifting platform 2 installed on the top of the lift 1, an audible and visual alarm installed on one side of the lifting platform 2, guardrails 3 installed on both sides of the top of the lifting platform 2, a fixing sleeve 4 provided on one side of each guardrail 3, a support rod 5 provided inside the fixing sleeve 4, and limit plates 33 integrally formed on both sides of the support rod 5. Limit grooves 32 are formed on both sides of the buffer sleeve 6. The two limit plates 33 are slidably connected to and adapted to the two limit grooves 32, thereby limiting the support rod 5. To improve the stability of the support rod 5, a buffer sleeve 6 is fitted on the outer side of the top of the support rod 5. A connecting pipe 7 is fixedly connected to the top of the buffer sleeve 6, and a warning rod 8 is inserted into the connecting pipe 7. A limit sleeve 9 is fixedly connected to one side of the buffer sleeve 6, and a guide plate 15 is fixedly connected to one side of the limit sleeve 9. A toothed plate 10 is slidably connected inside the guide plate 15. A guide gear 12 is provided at the bottom of the limit sleeve 9, and a rotating shaft 11 is fixedly connected inside the guide gear 12. The two ends of the rotating shaft 11 pass through the two side walls of the limit sleeve 9 and are rotatably connected to the limit sleeve 9. A connecting plate 16 is fixedly connected to both sides of the limit sleeve 9. Two connecting plates 16 are respectively fixedly connected to one side of a first buffer plate 17 and a second buffer plate 18. A first rotating plate 19 is disposed inside the first buffer plate 17, with first through holes 21 at both ends of the first rotating plate 19. A second rotating plate 20 is disposed inside the second buffer plate 18, with second through holes 22 at both ends of the second rotating plate 20. Both the first buffer plate 17 and the second buffer plate 18 are filled with buffer solution. A rotating shaft 11 passes through both ends of the first buffer plate 17 and the second buffer plate 18 respectively, and is rotatably connected to both the first buffer plate 17 and the second buffer plate 18. The rotating shaft 11 has external... One-way bearings 23 are fixedly connected to each side. The outer sides of the two one-way bearings 23 are fixedly connected to the first rotating plate 19 and the second rotating plate 20, respectively. The inner and outer rings of the two one-way bearings 23 have opposite limiting directions, so that when the guide gear 12 rotates in the forward direction, it drives the rotating shaft 11 to rotate in the forward direction, thereby driving the first rotating plate 19 to rotate. At this time, the second rotating plate 20 rotates relative to the rotating shaft 11. When the guide gear 12 rotates in the reverse direction, it drives the rotating shaft 11 and the second rotating plate 20 to rotate in the opposite direction, and causes the first rotating plate 19 to rotate relative to the rotating shaft 11, so that the toothed plate 10 forms different damping magnitudes when moving up and down.

[0024] A through groove 14 is provided on one side of the buffer sleeve 6, and one side of the guide gear 12 is disposed inside the through groove 14. A toothed groove 13 is provided on one side of the top of the support rod 5, and one side of the guide gear 12 is meshed with the toothed groove 13. The toothed plate 10 is meshed with the other side of the guide gear 12, so that the toothed plate 10 pushes the guide gear 12 and the rotating shaft 11 to rotate when it moves. An upper support plate 28 is fixedly connected to one side of the top of the toothed plate 10, and a vertical rod 30 is fixedly connected to the bottom of the upper support plate 28. A detection head 31 is fixedly connected to the bottom of the vertical rod 30, so that the toothed plate 10 drives the upper support plate 28 to rotate when it moves. When the upper support plate 28 moves, it drives the vertical rod 30 and the detection head 31 to move. The lower support plate 24 is fixedly connected to the bottom of the inner limit sleeve 9. The laser sensor 25 is fixedly connected to the top of the lower support plate 24. The support plate 26 is fixedly connected to the inner limit sleeve 9. The support plate 26 has a round hole 27 inside. The detection head 31 corresponds to the round hole 27 and the laser sensor 25. The spring 29 is fixedly connected to the top of the support plate 26. The top of the spring 29 is fixedly connected to the bottom of the upper support plate 28, so that the spring 29 supports the upper support plate 28.

[0025] The fixed sleeve 4 has support sleeves 39 fixedly connected to both its upper and lower ends. Slide grooves 40 are provided on both sides of the interior of each support sleeve 39. Two limiting plates 33 are slidably connected to and adapted to the two slide grooves 40 to limit the movement of the support rod 5. A clamping sleeve 38 is fixedly connected to one side of the fixed sleeve 4. The clamping sleeve 38 is fitted onto the outside of the guardrail 3, and both sides of the clamping sleeve 38 are fixed with bolts for easy fixation and support. A threaded rod 34 is threadedly connected to one side of the fixed sleeve 4. A clamping plate 3 is rotatably connected to one end of the threaded rod 34 inside the fixed sleeve 4. 5. Friction plates 36 are fixedly connected to both ends of the clamping plate 35. The clamping plate 35 is in contact with the outside of the support rod 5. The two friction plates 36 are respectively in contact with the two limiting plates 33. The threaded rod 34 is fixedly connected to a handle 37 at one end on the outside of the fixed sleeve 4. Rotating the handle 37 causes the threaded rod 34 to rotate, which in turn causes the threaded rod 34 to move inside the fixed sleeve 4. This causes the fixed sleeve 4 to move inside the clamping plate 35, which in turn causes the clamping plate 35 to move the friction plates 36. The friction plates 36 and the clamping plate 35 clamp and fix the support rod 5, which facilitates the adjustment of the height of the support rod 5.

[0026] In use, the handle 37 is clamped on the outside of the guardrail 3, and the sleeve 38 is fixed to the outside of the guardrail 3 with bolts. By manually rotating the handle 37, the handle 37 drives the threaded rod 34 to rotate, causing the threaded rod 34 to move horizontally. When the threaded rod 34 moves horizontally, it drives the clamping plate 35 and the friction plate 36 to move, causing the clamping plate 35 and the friction plate 36 to detach from the support rod 5. The support rod 5 can then be adjusted up and down inside the fixing sleeve 4 to adjust its height. After adjustment, the threaded rod 34 is screwed into the fixing sleeve 4, causing the clamping plate 35 and the friction plate 36 to lock the support rod 5, which is convenient for adapting to working environments of different heights.

[0027] The support rod 5 is installed on the guardrail 3 through the fixing sleeve 4. The fixing sleeve 4 has a clamp 38 and a bolt fixing structure on one side, which facilitates quick disassembly and position adjustment. At the same time, the support rod 5 is clamped and locked through the threaded rod 34, the clamping plate 35 and the friction plate 36, and guided by the limiting plate 33 and the sliding groove 40. It is easy to adjust and firmly fixed, adapting to different vehicle models and working height requirements, and has low installation and maintenance costs.

[0028] When the elevator 1 drives the lifting platform 2 and guardrail 3 to rise, it drives the support rod 5 and buffer sleeve 6 to rise, and also drives the connecting pipe 7 and warning rod 8 to rise. When the warning rod 8 encounters an obstacle, it causes the connecting pipe 7 to descend, and the buffer sleeve 6 to descend, causing the buffer sleeve 6 to slide down on the outside of the support rod 5, and causing the limiting sleeve 9 and the support rod 5 to move relative to each other. When the limiting sleeve 9 descends, it drives the guide gear 12 to descend, and causes the guide gear 12 to move relative to the support rod 5. The toothed groove 13 on one side of the support rod 5 pushes the guide gear 12 to rotate. The rotation of the guide gear 12 drives the toothed plate 10 to descend. When the toothed plate 10 descends, it drives the upper support plate 28 to descend, causing the upper support plate 28 to drive the vertical rod 30 and the detection head 31 to descend, so that the detection head 31 passes through the circular hole 27 and moves towards the laser sensor 25. The laser sensor 25 detects the position change of the detection head 31 and performs detection. If the change is large, it sends a signal to the warning device to issue a warning and controls the elevator 1 to shut down the electrical control system and stop the elevator 1 from rising.

[0029] When the buffer sleeve 6 descends slightly, it compresses the spring 29, causing the guide gear 12 to rotate and drive the rotating shaft 11 to rotate. The rotating shaft 11, in the direction of the descending toothed plate 10, drives the one-way bearing 23 and the first rotating plate 19 to rotate, locking the inner and outer rings of the one-way bearing 23 on the inner side of the first rotating plate 19, causing the first rotating plate 19 to rotate synchronously. When the first rotating plate 19 rotates inside the first buffer plate 17, because the diameter of the first through hole 21 is small, the buffer solution inside the first buffer plate 17 flows through the first through hole 21 during the rotation of the first rotating plate 19, forming a large damping effect, which slows down and buffers the rotation of the rotating shaft 11. Combined with the elasticity of the spring 29, it provides buffer support for the buffer sleeve 6, which can prevent the small vibrations generated during the normal operation of the elevator 1 from affecting the detection results and avoid false triggering of the alarm system.

[0030] By setting up a linkage structure between the warning rod 8 and the connecting pipe 7, when the warning rod 8 touches the obstacle above, it can drive the buffer sleeve 6 to slide down along the support rod 5, and then drive the guide gear 12 to rotate through the tooth groove 13, so that the tooth plate 10 drives the detection head 31 to descend and be identified by the laser sensor 25, thereby realizing a dual limit response of mechanical triggering and photoelectric detection. The structure is simple and the triggering is reliable.

[0031] When the buffer sleeve 6 rises and resets, the rotating shaft 11 rotates in the opposite direction to drive the second rotating plate 20 to rotate. The inner and outer rings of the one-way bearing 23 located inside the first rotating plate 19 rotate freely, causing the first rotating plate 19 and the rotating shaft 11 to rotate relative to each other, driving only the second rotating plate 20 to rotate. Because the diameter of the second through hole 22 is large, the damping effect is low. The elastic force of the spring 29 only supports the stable rising and resetting effect of the buffer sleeve 6, improving the stability of the buffer sleeve 6 during movement and reducing the impact force on the buffer sleeve 6.

[0032] This invention features a first buffer plate 17 and a second buffer plate 18 on both sides of the limiting sleeve 9, each filled with buffer solution. These buffer plates, along with a one-way bearing 23, a first rotating plate 19, and a second rotating plate 20, form a direction-dependent damping structure. When the toothed plate 10 descends, the first rotating plate 19 rotates, generating significant damping, which, combined with the spring 29, effectively suppresses minor vibrations that could trigger the system during normal operation. When the system rises and resets, the second rotating plate 20 rotates, generating less damping, ensuring a smooth reset of the buffer sleeve 6 and significantly improving the system's anti-interference capability and stability.

[0033] Example 2: Figure 15 As shown, a limit indication control system for aerial work platforms includes: The laser sensor 25 detects the position change of the detection head 31 in real time and outputs a detection signal; When the position change of the detection head 31 does not exceed the preset threshold, it is determined to be normal vibration and the machine will not be stopped. When the position change of the detection head 31 exceeds the preset threshold and continues for more than the set time, it is determined to be a real limit trigger event; After the controller determines that a real limit switch trigger event has occurred, it cuts off the lifting control circuit of elevator 1 and triggers the audible and visual alarm. After the obstacle is removed, the spring 29 pushes the detection head 31 to reset, the laser sensor 25 signal returns to normal, the controller cancels the shutdown alarm state, and the elevator 1 is allowed to rise again.

[0034] The laser sensor 25 monitors the position changes of the detection head 31 in real time, and sets a position change threshold and duration judgment logic. Only when the position change exceeds the threshold and lasts for a certain period of time is it determined to be a real limit event. The controller then cuts off the lifting control circuit of the elevator 1 and triggers an audible and visual alarm. This control system effectively distinguishes between normal vibration and real collision, avoids frequent accidental shutdowns, and ensures timely response when danger occurs, thereby improving the safety of high-altitude operations.

[0035] It will be apparent to those skilled in the art that the present invention is not limited to the details of the exemplary embodiments described above, and that the invention can be implemented in other specific forms without departing from its spirit or essential characteristics. Therefore, the embodiments should be considered in all respects as exemplary and non-limiting, and the scope of the invention is defined by the appended claims rather than the foregoing description. Thus, all variations falling within the meaning and scope of equivalents of the claims are intended to be included within the present invention. No reference numerals in the claims should be construed as limiting the scope of the claims.

Claims

1. A limit warning device for an aerial work platform, comprising a lift (1), a lifting platform (2) installed on the top of the lift (1), an audible and visual alarm installed on one side of the lifting platform (2), and guardrails (3) installed on both sides of the top of the lifting platform (2), characterized in that: Each of the two guardrails (3) is provided with a fixing sleeve (4) on one side. A support rod (5) is provided inside the fixing sleeve (4). A buffer sleeve (6) is fitted on the outer side of the top of the support rod (5). A connecting pipe (7) is fixedly connected to the top of the buffer sleeve (6). A warning rod (8) is inserted into the connecting pipe (7). A limit sleeve (9) is fixedly connected to one side of the buffer sleeve (6). A guide plate (15) is fixedly connected to one side of the limit sleeve (9). A toothed plate (10) is slidably connected inside the guide plate (15). A guide gear (12) is provided at the bottom of the limit sleeve (9). A guide gear (12) is fixedly connected inside the guide gear (12). There is a rotating shaft (11), and the two ends of the rotating shaft (11) pass through the two side walls of the limiting sleeve (9) and are rotatably connected to the limiting sleeve (9). The two sides of the limiting sleeve (9) are fixedly connected to a connecting plate (16). The two connecting plates (16) are fixedly connected to one side of a first buffer plate (17) and a second buffer plate (18). The first buffer plate (17) is provided with a first rotating plate (19) inside. The first rotating plate (19) is provided with a first through hole (21) at both ends. The second buffer plate (18) is provided with a second rotating plate (20) inside. The second rotating plate (20) is provided with a second through hole (22) at both ends.

2. The aerial work platform limit warning device according to claim 1, characterized in that: The first buffer plate (17) and the second buffer plate (18) are filled with buffer solution. The two ends of the rotating shaft (11) pass through the first buffer plate (17) and the second buffer plate (18) respectively and are rotatably connected to the first buffer plate (17) and the second buffer plate (18). One-way bearings (23) are fixedly connected to the outer sides of both ends of the rotating shaft (11). The outer sides of the two one-way bearings (23) are fixedly connected to the first rotating plate (19) and the second rotating plate (20) respectively. The inner and outer rings of the two one-way bearings (23) have opposite limiting directions.

3. The aerial work platform limit warning device according to claim 1, characterized in that: Both sides of the support rod (5) are integrally formed with limit plates (33), and both sides of the buffer sleeve (6) are provided with limit grooves (32). The two limit plates (33) are slidably connected to the two limit grooves (32) and are adapted to the two limit grooves (32).

4. The aerial work platform limit warning device according to claim 1, characterized in that: The buffer sleeve (6) has a through groove (14) on one side, the guide gear (12) is located inside the through groove (14) on one side, the support rod (5) has a tooth groove (13) on one side of the top end, the guide gear (12) is meshed with the tooth groove (13) on one side, and the tooth plate (10) is meshed with the guide gear (12) on the other side.

5. The aerial work platform limit warning device according to claim 1, characterized in that: An upper support plate (28) is fixedly connected to one side of the top of the toothed plate (10), a vertical rod (30) is fixedly connected to the bottom of the upper support plate (28), and a detection head (31) is fixedly connected to the bottom of the vertical rod (30).

6. The aerial work platform limit warning device according to claim 5, characterized in that: The bottom of the limiting sleeve (9) is fixedly connected to a lower support plate (24), the top of the lower support plate (24) is fixedly connected to a laser sensor (25), the inside of the limiting sleeve (9) is fixedly connected to a support plate (26), the inside of the support plate (26) is provided with a round hole (27), the detection head (31) corresponds to the round hole (27) and the laser sensor (25), the top of the support plate (26) is fixedly connected to a spring (29), the top of the spring (29) is fixedly connected to the bottom of the upper support plate (28).

7. The aerial work platform limit warning device according to claim 3, characterized in that: The fixed sleeve (4) has a support sleeve (39) fixedly connected to both the upper and lower ends inside. The two support sleeves (39) have sliding grooves (40) on both sides inside. The two limiting plates (33) are slidably connected to the two sliding grooves (40) and are adapted to the two sliding grooves (40).

8. The aerial work platform limit warning device according to claim 1, characterized in that: A sleeve (38) is fixedly connected to one side of the fixed sleeve (4). The sleeve (38) is fitted on the outside of the guardrail (3). The two sides of the sleeve (38) are fixed by bolts.

9. The aerial work platform limit warning device according to claim 1, characterized in that: A threaded rod (34) is threadedly connected to one side of the fixed sleeve (4). A clamping plate (35) is rotatably connected to one end of the threaded rod (34) inside the fixed sleeve (4). Friction plates (36) are fixedly connected to both ends of the clamping plate (35). The clamping plate (35) is in contact with the outside of the support rod (5). The two friction plates (36) are in contact with the two limiting plates (33) respectively. A handle (37) is fixedly connected to one end of the threaded rod (34) outside the fixed sleeve (4).

10. A limit indicator control system for aerial work platforms, applicable to the limit warning device for aerial work platforms as described in any one of claims 1-9, characterized in that, include: The laser sensor (25) detects the position change of the detection head (31) in real time and outputs a detection signal; When the position change of the detection head (31) does not exceed the preset threshold, it is determined to be normal vibration and the machine will not be stopped. When the position change of the detection head (31) exceeds the preset threshold and continues for more than the set time, it is determined to be a real limit trigger event; After the controller determines that a real limit trigger event has occurred, it cuts off the lifting control circuit of the elevator (1) and triggers the audible and visual alarm. After the obstacle is removed, the spring (29) pushes the detection head (31) to reset, the laser sensor (25) signal returns to normal, the controller cancels the shutdown alarm state, and allows the elevator (1) to rise again.

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