阅读说明：本技术 一种智能电网用运维小车 (Operation and maintenance trolley for smart power grid ) 是由 顾振飞 毛宇鹏 陈勇 汤昕怡 王文轩 李维勇 王文锋 于 2021-07-29 设计创作，主要内容包括：本发明公开了一种智能电网用运维小车,属于电网维护技术领域,包括车体和驱动履带,车体的一端设置有驱动履带,所述车体的另一端设置有维护机构,维护机构包括用于对物体进行吊运的吊运组件、用于对吊运组件的位置进行调节的调节组件以及用于防止物体在吊运过程中发生摆动的防护组件,所述吊运组件包括第一限位板,第一限位板的一侧间隔设置有第二限位板,第一限位板的一端设置有用于对于第二限位板的位置进行调节的高度调节件；本发明结构简单,使用方便,使用时通过限位组件和防坠组件的相互配合,避免挂钩在吊运物体的过程中发生摆动,从而防止被吊运的物体由于风力等外界因素而发生摆动,使运维小车的使用更加安全。(The invention discloses a maintenance trolley for an intelligent power grid, which belongs to the technical field of power grid maintenance and comprises a trolley body and a driving crawler, wherein the driving crawler is arranged at one end of the trolley body, a maintenance mechanism is arranged at the other end of the trolley body, the maintenance mechanism comprises a hoisting component for hoisting an object, an adjusting component for adjusting the position of the hoisting component and a protecting component for preventing the object from swinging in the hoisting process, the hoisting component comprises a first limiting plate, second limiting plates are arranged at intervals on one side of the first limiting plate, and a height adjusting piece for adjusting the position of the second limiting plate is arranged at one end of the first limiting plate; the anti-falling trolley is simple in structure and convenient to use, and when the anti-falling trolley is used, the limit component and the anti-falling component are matched with each other, so that the hook is prevented from swinging in the process of lifting an object, the lifted object is prevented from swinging due to external factors such as wind power and the like, and the operation and maintenance trolley is safer to use.)

1. The utility model provides an operation and maintenance dolly for smart power grids, includes automobile body (2) and drive track (4), and the one end of automobile body (2) is provided with drive track (4), its characterized in that: the other end of automobile body (2) is provided with maintains mechanism (3), maintains mechanism (3) including the handling subassembly that is used for carrying out the handling to the object, be used for adjusting the adjusting part of handling the position of subassembly and be used for preventing that the object from taking place wobbling protection component at the handling in-process.

2. The operation and maintenance trolley for the smart grid as claimed in claim 1, wherein: the lifting assembly comprises a first limiting plate (31), a second limiting plate (378), a height adjusting piece (32), a winch (374), a third limiting plate (379), a hook (383), a traction rope (375), a first fixed pulley (377) and a second fixed pulley (382), wherein the first limiting plate (31) is arranged on the adjusting assembly, the second limiting plate (378) is arranged on one side of the first limiting plate (31) at intervals, the height adjusting piece (32) used for adjusting the position of the second limiting plate (378) is arranged at one end of the first limiting plate (31), the winch (374) is arranged at the other end of the first limiting plate (31), the third limiting plate (379) is arranged on the side surface of the second limiting plate (378), the hook (383) is arranged on one side of the third limiting plate (379), the traction rope (375) is arranged at the joint of the hook (383) and the winch (374), and two ends of the second limiting plate (378) are provided with first fixed pulleys (377) corresponding to the traction rope (375), and one end, far away from the second limiting plate (378), of the third limiting plate (379) is provided with a second fixed pulley (382) corresponding to the traction rope (375).

3. The operation and maintenance trolley for the smart grid as claimed in claim 2, wherein: one end of the height adjusting piece (32) is provided with a monitoring camera (376).

4. The operation and maintenance trolley for the smart grid as claimed in claim 2, wherein: the adjusting part comprises a first limiting base (36), a first limiting slide rail (33), a first limiting sleeve (34) and a driving part, the first limiting base (36) is arranged at the top of the vehicle body, the first limiting slide rail (33) is arranged inside the first limiting base (36), the two ends of the first limiting slide rail (33) are slidably connected with the first limiting sleeve (34) corresponding to the first limiting plate (31), and the driving part used for driving the first limiting sleeve (34) to move is further arranged inside the first limiting base (36).

5. The operation and maintenance trolley for the smart grid as claimed in claim 4, wherein: the drive assembly comprises a limiting screw rod (371), a limiting sliding block (35) and a driver (373), the limiting screw rod (371) is rotatably connected with a first limiting base (36), the limiting sliding block (35) corresponding to a first limiting sleeve (34) is in threaded connection with the two ends of the limiting screw rod (371), and the driver (373) used for driving the limiting screw rod (371) to rotate is arranged at the two ends of the first limiting base (36).

6. The operation and maintenance trolley for the smart grid as claimed in claim 5, wherein: the protection component comprises a second limiting base (381), a limiting component and an anti-falling component, wherein the second limiting base (381) is arranged at the bottom of a third limiting plate (379), one end of the second limiting base (381) is provided with the limiting component used for preventing the hook (383) from swinging, and the other end of the second limiting slide rail (391) is provided with the anti-falling component used for preventing the hook (383) from accidentally falling.

7. The operation and maintenance trolley for the smart grid as claimed in claim 6, wherein: the limiting assembly comprises a third limiting slide rail (392), a second limiting sleeve (396), a connecting plate (395), a first anti-falling plate (394) and a second protective magnetic plate (384), the third limiting slide rail (392) is arranged inside a second limiting base (381) along the vertical direction, one end of the third limiting slide rail (392) is connected with the second limiting sleeve (396) in a sliding mode, the connecting plate (395) corresponding to the hook (383) is arranged on the side face of the second limiting sleeve (396), the first anti-falling plate (394) is arranged on the other side of the second limiting sleeve (396), and the second protective magnetic plate (384) is arranged at one end of the first anti-falling plate (394).

8. The operation and maintenance trolley for the smart grid as claimed in claim 7, wherein: the anti-falling assembly comprises a fourth limiting plate (385), a second limiting sliding rail (391), a reset spring (389), a limiting frame (393), a second anti-falling plate (397), a first protective magnetic plate (372), an electromagnet (388) and a driving iron plate (386), wherein two ends of the fourth limiting plate (385) are connected between the third limiting sliding rail (392) and the inner wall of a second limiting base (381) in a sliding mode through the second limiting sliding rail (391), the reset spring (389) used for driving the fourth limiting plate (385) to be close to the third limiting sliding rail (392) is arranged at two ends of the second limiting base (381), the limiting frame (393) is arranged on the side face of the fourth limiting plate (385), the second anti-falling plate (397) corresponding to the first anti-falling plate (394) is connected at one end of the limiting frame (393) in a rotating mode, the first protective magnetic plate (372) used for reducing noise in cooperation with the second protective magnetic plate (384) is arranged at one end of the second anti-falling plate (397), an electromagnet (388) is arranged inside the second limiting base (381), and a driving iron plate (386) used for being matched with the electromagnet (388) to adjust the position of the fourth limiting plate (385) is arranged on the side face of the fourth limiting plate (385).

9. The operation and maintenance trolley for the smart grid as claimed in claim 8, wherein: and an elastic buffer plate (387) used for reducing noise is arranged on the side surface of the electromagnet (388).

10. The operation and maintenance trolley for the smart grid according to any one of claims 1 to 9, wherein: two ends of the vehicle body (2) are movably connected with a box door (1).

Technical Field

The invention relates to an operation and maintenance trolley for an intelligent power grid, and belongs to the technical field of power grid maintenance.

Background

The power grid needs to be maintained regularly in the using process so as to eliminate faults or potential safety hazards in the power grid and ensure the normal operation of the power grid, and in order to reduce the labor intensity of workers, the power grid is often maintained by an operation and maintenance trolley in the prior art;

the traditional operation and maintenance trolley comprises a trolley body, a hook, a fixing plate, a fixing rod, a gear and the like, and has the advantages that wheels can be contracted, the stability and convenience of the trolley are improved, and an object can be hoisted;

however, the operation and maintenance trolley is lack of a protection structure, so that when the operation and maintenance trolley is used for lifting objects, the lifted objects are easy to swing due to external factors such as wind power, and potential safety hazards exist in the use of the operation and maintenance trolley.

Disclosure of Invention

The invention aims to overcome the defects in the prior art and provide an operation and maintenance trolley for a smart grid, so as to solve the problems in the background art.

In order to achieve the purpose, the invention is realized by adopting the following technical scheme:

the invention provides an operation and maintenance trolley for a smart grid, which comprises a trolley body and a driving crawler, wherein one end of the trolley body is provided with the driving crawler, and the operation and maintenance trolley is characterized in that: the other end of the car body is provided with a maintenance mechanism, and the maintenance mechanism comprises a lifting component for lifting objects, an adjusting component for adjusting the position of the lifting component and a protection component for preventing the objects from swinging in the lifting process.

Preferably, the hoisting assembly comprises a first limit plate, a second limit plate, a height adjusting piece, a winch, a third limit plate, a hook, a traction rope, a first fixed pulley and a second fixed pulley, the first limit plate is arranged on the adjusting component, one side of the first limit plate is provided with second limit plates at intervals, one end of the first limit plate is provided with a height adjusting piece used for adjusting the position of the second limit plate, the other end of the first limit plate is provided with a winch, the side surface of the second limit plate is provided with a third limit plate, a hook is arranged on one side of the third limit plate, a traction rope is arranged at the joint of the hook and the winch, and first fixed pulleys corresponding to the traction ropes are arranged at two ends of the second limiting plate, and a second fixed pulley corresponding to the traction rope is arranged at one end, far away from the second limiting plate, of the third limiting plate.

Preferably, one end of the height adjusting piece is provided with a monitoring camera.

Preferably, the adjusting part comprises a first limiting base, a first limiting slide rail, a first limiting sleeve and a driving part, the first limiting base is arranged at the top of the vehicle body, the first limiting slide rail is arranged in the first limiting base, the two ends of the first limiting slide rail are slidably connected with the first limiting sleeve corresponding to the first limiting plate, and the driving part used for driving the first limiting sleeve to move is further arranged in the first limiting base.

Preferably, the driving assembly comprises a limiting screw rod, a limiting sliding block and a driver, the limiting screw rod is rotatably connected with the first limiting base, the limiting sliding block corresponding to the first limiting sleeve is in threaded connection with the two ends of the limiting screw rod, and the driver used for driving the limiting screw rod to rotate is arranged at the two ends of the first limiting base.

Preferably, the protection component comprises a second limiting base, a limiting component and an anti-falling component, the second limiting base is arranged at the bottom of the third limiting plate, one end of the second limiting base is provided with the limiting component used for preventing the hook from swinging, and the other end of the second limiting slide rail is provided with the anti-falling component used for preventing the hook from accidentally falling.

Preferably, the limiting assembly comprises a third limiting slide rail, a second limiting sleeve, a connecting plate, a first anti-falling plate and a second protective magnetic plate, the third limiting slide rail is arranged inside the second limiting base along the vertical direction, one end of the third limiting slide rail is connected with the second limiting sleeve in a sliding mode, the side face of the second limiting sleeve is provided with the connecting plate corresponding to the hook, the other side of the second limiting sleeve is provided with the first anti-falling plate, and one end of the first anti-falling plate is provided with the second protective magnetic plate.

Preferably, the anti-falling assembly comprises a fourth limiting plate, a second limiting slide rail, a return spring, a limiting frame, a second anti-falling plate, a first protective magnetic plate, an electromagnet and a driving iron plate, two ends of the fourth limiting plate are connected between the third limiting slide rail and the inner wall of the second limiting base in a sliding way through the second limiting slide rail, two ends of the second limiting base are provided with a return spring for driving the fourth limiting plate to be close to the third limiting slide rail, a limit frame is arranged on the side surface of the fourth limit plate, one end of the limit frame is rotationally connected with a second anti-falling plate corresponding to the first anti-falling plate, one end of the second anti-falling plate is provided with a first protection magnetic plate which is matched with the second protection magnetic plate for noise reduction, the inside of the second limiting base is provided with an electromagnet, and the side face of the fourth limiting plate is provided with a driving iron plate which is used for being matched with the electromagnet to adjust the position of the fourth limiting plate.

Preferably, the side of the electromagnet is provided with an elastic buffer plate for reducing noise.

Preferably, two ends of the vehicle body are movably connected with the box doors.

Compared with the prior art, the invention has the following beneficial effects: the lifting device is simple in structure and convenient to use, and when the lifting device is used, the limit component and the anti-falling component are matched with each other, so that the hook is prevented from swinging in the process of lifting an object, the lifted object is prevented from swinging due to external factors such as wind power and the like, the operation and maintenance trolley is safer to use, and the lifting device can prevent the lifted object from falling due to the fracture of the traction rope, further improve the safety of the operation and maintenance trolley.

Drawings

FIG. 1 is a schematic structural diagram of an operation and maintenance trolley for a smart grid;

FIG. 2 is a schematic structural diagram of a maintenance mechanism in an operation and maintenance trolley for a smart grid;

fig. 3 is a schematic structural diagram of a second limiting base in the operation and maintenance trolley for the smart grid;

fig. 4 is a schematic structural diagram of a limiting frame in an operation and maintenance trolley for a smart grid.

In the figure: 1. a box door; 2. a vehicle body; 3. a maintenance mechanism; 4. driving the caterpillar; 31. a first limit plate; 32. a height adjustment member; 33. a first limiting slide rail; 34. a first limit sleeve; 35. a limiting slide block; 36. a first limit base; 371. a limiting screw rod; 372. a first shield magnetic plate; 373. a driver; 374. a winch; 375. a hauling rope; 376. a surveillance camera; 377. a first fixed pulley; 378. a second limiting plate; 379. a third limiting plate; 381. a second limiting base; 382. a second fixed pulley; 383. hooking; 384. a second shield magnetic plate; 385. a fourth limiting plate; 386. driving the iron plate; 387. an elastic buffer plate; 388. an electromagnet; 389. a return spring; 391. a second limiting slide rail; 392. a third limiting slide rail; 393. a limiting frame; 394. a first fall arrest plate; 395. a connecting plate; 396. a second limit sleeve; 397. and a second anti-falling plate.

Detailed Description

The invention is further described below with reference to the accompanying drawings. The following examples are only for illustrating the technical solutions of the present invention more clearly, and the protection scope of the present invention is not limited thereby.

In the description of the present invention, it is to be understood that the terms "center", "longitudinal", "lateral", "up", "down", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer", and the like, indicate orientations or positional relationships based on those shown in the drawings, and are used only for convenience in describing the present invention and for simplicity in description, and do not indicate or imply that the referenced devices or elements must have a particular orientation, be constructed and operated in a particular orientation, and thus, are not to be construed as limiting the present invention. Furthermore, the terms "first", "second", etc. are used for descriptive purposes only and are not to be construed as indicating or implying relative importance or implicitly indicating the number of technical features indicated. Thus, a feature defined as "first," "second," etc. may explicitly or implicitly include one or more of that feature. In the description of the present invention, "a plurality" means two or more unless otherwise specified.

In the description of the present invention, it should be noted that, unless otherwise explicitly specified or limited, the terms "mounted," "connected," and "connected" are to be construed broadly, e.g., as meaning either a fixed connection, a removable connection, or an integral connection; can be mechanically or electrically connected; they may be connected directly or indirectly through intervening media, or they may be interconnected between two elements. The specific meaning of the above terms in the present invention can be understood by those of ordinary skill in the art through specific situations.

Please refer to fig. 1, the embodiment provides a maintenance trolley for a smart grid, which includes a trolley body 2 and a driving crawler 4, wherein the driving crawler 4 is disposed at one end of the trolley body 2, the driving crawler 4 is used in the prior art, a maintenance mechanism 3 is disposed at the other end of the trolley body 2, and the maintenance mechanism 3 includes a lifting component for lifting an object, an adjusting component for adjusting the position of the lifting component, and a protection component for preventing the object from swinging in the lifting process.

Referring to fig. 1 and 2, in an embodiment, in order to make the application range of the lifting assembly wider, in the embodiment, preferably, the lifting assembly includes a first limiting plate 31, a second limiting plate 378, a height adjusting member 32, a winch 374, a third limiting plate 379, a hook 383, a pulling rope 375, a first fixed pulley 377, and a second fixed pulley 382, the first limiting plate 31 is disposed on the adjusting assembly, the second limiting plate 378 is disposed at an interval on one side of the first limiting plate 31, the height adjusting member 32 for adjusting the position of the second limiting plate 378 is disposed at one end of the first limiting plate 31, the winch 374 is disposed at the other end of the first limiting plate 31, the third limiting plate 379 is disposed on a side of the second limiting plate 378, the hook 383 is disposed on one side of the third limiting plate 379, the pulling rope 375 is disposed at a connection position of the hook 383 and the winch 374, the two ends of the second limiting plate 378 are provided with a first fixed pulley 377 corresponding to the pulling rope 375, and one end of the third limiting plate 379 far away from the second limiting plate 378 is provided with a second fixed pulley 382 corresponding to the pulling rope 375.

Referring to fig. 2, in an embodiment, in order to make the functions of the lifting assembly more abundant, in this embodiment, preferably, one end of the height adjusting member 32 is provided with a monitoring camera 376, and the monitoring camera 376 is a high-definition night vision camera;

in another embodiment, in order to lower the cost of the hoisting assembly, in this embodiment, preferably, the hoisting assembly includes a first limiting plate 31, a second limiting plate 378 is disposed at an interval on one side of the first limiting plate 31, a hook 383 is disposed on one side of the second limiting plate 378, a winch 374 is disposed at the other end of the second limiting plate 378, a steel wire rope is disposed at a connection position between the winch 374 and the hook 383, a motor is disposed on a side surface of the first limiting plate 31, a threaded rod is disposed at one end of the motor, which is far away from the first limiting plate 31, a driving sleeve rotatably connected with the second limiting plate 378 is in threaded connection with one end of the threaded rod, which is far away from the motor, and the height of the second limiting plate 378 is adjusted by the mutual matching of the motor, the threaded rod and the driving sleeve when the hoisting assembly is used;

referring to fig. 2, in an embodiment, in order to make the use of the adjusting assembly more convenient, in the embodiment, preferably, the adjusting assembly includes a first limiting base 36, a first limiting slide rail 33, a first limiting sleeve 34, and a driving assembly, the first limiting base 36 is disposed at the top of the vehicle body 2, the first limiting slide rail 33 is disposed inside the first limiting base 36, two ends of the first limiting slide rail 33 are slidably connected with the first limiting sleeve 34 corresponding to the first limiting plate 31, and the driving assembly for driving the first limiting sleeve 34 to move is further disposed inside the first limiting base 36.

Referring to fig. 2, in an embodiment, in order to make the use of the driving assembly more reliable, in this embodiment, preferably, the driving assembly includes a limit screw rod 371, a limit slider 35, and a driver 373, the limit screw rod 371 is rotatably connected with a first limit base 36, two ends of the limit screw rod 371 are in threaded connection with the limit slider 35 corresponding to a first limit sleeve 34, two ends of the first limit base 36 are provided with the drivers 373 for driving the limit screw rod 371 to rotate, and the drivers 373 are motors or pneumatic motors;

in another embodiment, in order to make the cost of the adjusting assembly lower, in this embodiment, preferably, the adjusting assembly includes a first limiting base 36, two ends of the first limiting base 36 are provided with hydraulic cylinders, one end of the hydraulic cylinder, which is far away from the first limiting base 36, is provided with a driving plate corresponding to the first limiting plate 31, and when in use, the first limiting plate 31 is driven to move by the mutual cooperation of the hydraulic cylinders and the driving plate;

referring to fig. 2 and fig. 3, in an embodiment, in order to make the protection effect of the protection assembly better, in this embodiment, preferably, the protection assembly includes a second limit base 381, a limit assembly, and an anti-falling assembly, where the second limit base 381 is welded to the bottom of the third limit plate 379, one end of the second limit base 381 is provided with the limit assembly for preventing the hook 383 from swinging, and the other end of the second limit sliding rail 391 is provided with the anti-falling assembly for preventing the hook 383 from accidentally falling.

Referring to fig. 3, in an embodiment, in order to improve the limiting effect of the limiting assembly, in this embodiment, preferably, the limiting assembly includes a third limiting slide rail 392, a second limiting sleeve 396, a connecting plate 395, a first anti-falling plate 394, and a second protective magnetic plate 384, the third limiting slide rail 392 is disposed inside the second limiting base 381 along the vertical direction, one end of the third limiting slide rail 392 is slidably connected with the second limiting sleeve 396, a connecting plate 395 corresponding to the hook 383 is disposed on a side surface of the second limiting sleeve 396, a first anti-falling plate 394 is disposed on the other side of the second limiting sleeve 396, and a second protective magnetic plate 384 is disposed on one end of the first anti-falling plate 394.

Referring to fig. 3 and 4, in order to reduce the failure rate of the anti-falling assembly, in this embodiment, preferably, the anti-falling assembly includes a fourth limiting plate 385, a second limiting slide rail 391, a return spring 389, a limiting frame 393, a second anti-falling plate 397, a first magnetic shield plate 372, an electromagnet 388, and a driving iron plate 386, two ends of the fourth limiting plate 385 are slidably connected between the third limiting slide rail 392 and an inner wall of the second limiting base 381 through the second limiting slide rail 391, two ends of the second limiting base 381 are provided with the return spring 389 for driving the fourth limiting plate 385 to approach the third limiting slide rail 392, a limiting frame 393 is arranged on a side surface of the fourth limiting plate 385, one end of the limiting frame 393 is rotatably connected with the second anti-falling plate 397 corresponding to the first anti-falling plate 394, and the second anti-falling plate 397 can rotate 90 ° counterclockwise, the one end that the board 397 was prevented weighing down to the second is provided with the first protection magnetic sheet 372 that the cooperation second protection magnetic sheet 384 made an uproar fall, the inside of second limit base 381 is provided with the electro-magnet 388, the side of fourth limiting plate 385 is provided with and is used for cooperating the electro-magnet 388 to carry out the drive iron plate 386 that adjusts to the position of fourth limiting plate 385.

When the first anti-falling plate 394 moves downwards, the first protection magnetic plate 372 and the second protection magnetic plate 384 repel each other, at the moment, the second anti-falling plate 397 is tightly attached to the limiting frame 393 due to the mutual repulsion of the first protection magnetic plate 372 and the second protection magnetic plate 384, the phenomenon that the second anti-falling plate 397 and the limiting frame 393 are violently installed due to the falling of the first anti-falling plate 394 is avoided, and the service life of the assembly is prolonged;

referring to fig. 3, in an embodiment, in order to reduce noise generated when the electromagnet 388 collides with the driving iron plate 386, in this embodiment, preferably, an elastic buffer plate 387 for reducing noise is disposed on a side surface of the electromagnet 388, and a material of the elastic buffer plate 387 is not limited, in this embodiment, preferably, the material of the elastic buffer plate 387 is rubber or silicone;

in another embodiment, in order to make the cost of the protection assembly lower, in this embodiment, preferably, the protection assembly includes a second limit base 381, a third limit slide rail 392 at one end of the second limit base 381, a second limit sleeve 396 is slidably connected to one end of the third limit slide rail 392, a telescopic connecting rod corresponding to the hook 383 is disposed on a side surface of the second limit sleeve 396, an electric hydraulic cylinder corresponding to the third limit slide rail 392 is disposed on the other side of the second limit sleeve 396, and the second limit sleeve 396 is fixed by extending the electric hydraulic cylinder when in use;

referring to fig. 1, in an embodiment, in order to enrich the carrying function of the vehicle body 2, in this embodiment, it is preferable that two ends of the vehicle body 2 are movably connected with a box door 1, when in use, the box door 1 is opened, and then a tool commonly used for maintenance is placed inside the vehicle body 2 for transportation.

The working principle and the using process of the invention are as follows: when the trolley is used, a power grid is maintained through the operation and maintenance trolley, when objects need to be lifted, the objects are hung on the hook 383, a power supply of the winch 374 is switched on, the traction rope 375 is wound through the winch 374, so that the objects are lifted, and in the lifting process, the hook 383 is prevented from swinging through the connecting plate 395, so that the lifted objects are prevented from swinging due to external factors such as wind power and the like, and the operation and maintenance trolley is safer to use;

when the hauling rope 375 is broken accidentally, the hook 383 hung with articles falls, the first anti-falling plate 394 moves downwards, the second anti-falling plate 397 supports the first anti-falling plate 394, the hook 383 is prevented from falling freely, and therefore the safety of the operation and maintenance trolley is improved remarkably;

secondly, when the hook 383 needs to fall normally, the power supply of the electromagnet 388 is connected, at the moment, the electromagnet 388 drives the driving iron plate 386 to enable the driving iron plate 386 to drive the fourth limiting plate 385 to move towards the direction close to the electromagnet 388, at the moment, the second anti-falling plate 397 loses the linkage locking effect on the first anti-falling plate 394, so that the hook 383 can fall normally, and the hook 383 is worthy of popularization and use.

The above description is only a preferred embodiment of the present invention, and it should be noted that, for those skilled in the art, several modifications and variations can be made without departing from the technical principle of the present invention, and these modifications and variations should also be regarded as the protection scope of the present invention.