Power grid line monitoring equipment

Abstract

The utility model discloses a power grid line monitoring device, which relates to the technical field of power grid line monitoring and comprises a main frame, a first traveling wheel and a second traveling wheel are symmetrically arranged in the main frame, and a first transmission case and a second transmission case are rotatably arranged on rotating shafts on two sides of the first traveling wheel and the second traveling wheel respectively. Driving assemblies are arranged in the first transmission box and the second transmission boxes, guide sliding rods are symmetrically arranged on one sides of the second transmission boxes, a threaded rod is arranged in a threaded hole in the upper end of a mounting block on one side of one second transmission box, a rotating block is rotationally arranged at one end of the threaded rod, and a cleaning mechanism is arranged in one end of the main frame. The cross sections of the first walking wheel and the second walking wheel are arranged in an arc shape, so that the cable is prevented from deviating from the detection position of the detection component when the main frame moves, and meanwhile, the cable is convenient to clean by arranging the first brush roller and the second brush roller.

Description

Technical Field

[0001] The utility model relates to the technical field of power grid line monitoring, in particular to power grid line monitoring equipment. Background Art

[0002] Power lines refer to the lines used to transmit electric energy between power plants, substations and power users. It is an important part of the power supply system and is responsible for the transmission and distribution of electric energy. Ensure the quality of line erection, strengthen operation and maintenance, and improve the reliability of power supply to users. Because overhead lines are placed in the open air for a long time, the components of the lines are not only subject to normal electrical and mechanical loads, but also to natural and man-made external conditions such as wind, rain, ice, snow, air pollution, lightning, etc., which affect each line and component, causing line damage and inability to work normally. It needs to be monitored and maintained by equipment.

[0003] Chinese Patent: CN220086804U discloses a national power grid line monitoring and maintenance device. The device is provided with a walking mechanism. The bidirectional screw rod rotates through the slider and the connecting plate to drive the connecting rod, the first walking wheel and the second walking wheel to move, so that the two sets of first walking wheels and the second walking wheels are close to each other and clamp the line to ensure the stability of the monitoring frame on the line. At this time, the worker can loosen the monitoring frame, and the corresponding connecting rod rotates to drive the two first walking wheels and the second walking wheels to rotate, so that the two sets of first walking wheels and the second walking wheels can walk on the line, and the monitoring frame can monitor while walking on the line. When the monitoring frame detects a problem with the line, the monitoring frame will sound an alarm to remind the workers that the line needs maintenance, thereby reducing the tediousness of workers manually pushing the monitoring and maintenance device forward and allowing workers to do other work during monitoring. However, the cables are exposed to the outside for a long time, so that a lot of dust will adhere to the surface of the cables, which will cause inaccurate monitoring data during detection. In addition, the running wheels of the above-mentioned monitoring device are cylindrical, and the monitoring component is in the middle. When monitoring the cables, the monitoring frame is prone to tilting, so that the cables are at the end of the running wheels, which makes the detection component unable to monitor the cables, making it inconvenient for actual use.

[0004] Based on this, a power grid line monitoring device is now provided, which can eliminate the disadvantages of existing devices. Utility Model Content

[0005] The utility model aims to provide a power grid line monitoring device to solve the problems in the background art that it is inconvenient to clean the cable surface and the cable is inconvenient to align with the monitoring component.

[0006] In order to achieve the above purpose, the utility model provides the following technical solutions:

[0007] A power grid line monitoring device comprises a main frame, a handle is fixedly provided on the upper end of the main frame, a first walking wheel and a second walking wheel are symmetrically provided inside the main frame, a connecting support plate is rotatably provided between the rotating shafts on both sides of the two first walking wheels and the second walking wheels, a first transmission box and a second transmission box are rotatably provided on the rotating shafts on both sides of the first walking wheels and the second walking wheels, a driving assembly for driving the two first walking wheels and the second walking wheels to rotate is provided inside the first transmission box and the second transmission box, the two first transmission boxes are fixedly provided at the bottom end of the inner side of the main frame, a detection component is fixedly provided between the two connecting support plates, a guide slide bar is symmetrically provided on one side of the second transmission box, a guide slide groove is provided at the corresponding position of the guide slide bar at the inner upper end of the main frame, a threaded rod is provided in the threaded hole on the upper end of the mounting block on one side of the second transmission box, a rotating block is rotatably provided at one end of the threaded rod, the rotating block is fixedly provided on one side of the first transmission box, the threaded rod is rotatably provided in the mounting hole at the upper end of the main frame, and a cleaning mechanism for cleaning cables is provided inside one end of the main frame.

[0008] On the basis of the above technical solutions, the present invention also provides the following optional technical solutions:

[0009] The transmission gear of the present invention is a gear selected from the group consisting of a first gear and a second gear selected from the group consisting of a first gear and a second gear selected from the group consisting of a first gear and a second gear selected from the group consisting of a first gear and a second gear selected from the group consisting of a first gear and a second gear selected from the group consisting of a first gear and a second gear selected from the group consisting of a first gear and a second gear selected from the group consisting of a first gear and a second gear selected from the group consisting of a first gear and a second gear selected from the group consisting of a

[0010] In an optional scheme: the cleaning mechanism includes a first brush roller and a second brush roller, each of the first brush roller and the second brush roller is provided with a plurality of bristles, the first brush roller and the second brush roller are respectively arranged at positions corresponding to the first walking wheel and the second walking wheel inside the main frame, a first rotating plate and a second rotating plate are rotatably provided on the rotating columns at both ends of the first brush roller and the second brush roller, the two first rotating plates are respectively fixed on one side of the two first transmission boxes, the two second rotating plates are respectively fixed on one side of the two second transmission boxes, a second driven wheel and a third driven wheel are respectively fixed on the rotating shafts at one end of the first brush roller and the second brush roller, the second driven wheel and the third driven wheel are respectively connected to the second driving wheel and the third driving wheel on the rotating shaft on one side of the first walking wheel and the second walking wheel through the second belt and the third belt, and a rectangular through-hole is provided at the bottom end of the main frame corresponding to the positions of the first brush roller and the second brush roller.

[0011] In an optional solution, the first brush roller and the second brush roller are installed in a staggered manner.

[0012] In an optional solution: combing plates are fixedly provided inside the main frame at positions corresponding to the positions of the first brush roller and the second brush roller, and a plurality of combing grooves are provided on one side of the combing plate.

[0013] In an optional solution: a baffle is fixedly provided on one side of the first transmission box and the second transmission box close to the comb plate.

[0014] In an optional solution: a plurality of balls are provided on the inner side of the baffle.

[0015] In an optional scheme: a rotating seat is symmetrically provided on one side of the main frame, a protective plate is rotatably provided on the rotating seat, a limit plate is tightly provided on one side of the protective plate, the limit plate is slidably provided inside the fixed tube, the fixed tube is fixed on one side of the main frame, a return spring is fixed between one end of the limit plate and one side inside the fixed tube, a shift plate is fixed on the upper end of the limit plate, and a sliding groove is provided at the upper end of the fixed tube corresponding to the position of the shift plate.

[0016] Compared with the prior art, the utility model has the following beneficial effects:

[0017] The utility model arranges the first walking wheel and the second walking wheel in an arc-shaped cross-section, thereby facilitating that the cable is always located in the middle of the first walking wheel and the second walking wheel, thereby preventing the cable from deviating from the detection position of the detection component when the main frame moves; at the same time, by arranging the first brush roller and the second brush roller, the first brush roller and the second brush roller are respectively driven to rotate when the first walking wheel and the second walking wheel rotate; the first brush roller and the second brush roller facilitate cleaning of the cable through a plurality of bristles, thereby maintaining the accuracy of the cable detection value of the detection component; by symmetrically arranging two protective plates on one side of the main frame, the protective plates can be quickly fixed by the limit plate to prevent them from falling when the main frame is working, thereby increasing the practicability of the power grid line detection equipment. BRIEF DESCRIPTION OF THE DRAWINGS

[0018] Figure 1 It is a structural schematic diagram of the utility model.

[0019] Figure 2 This is a schematic diagram of the internal structure of the first transmission box of the utility model.

[0020] Figure 3 This is a schematic diagram of the installation of the electric motor of the utility model.

[0021] Figure 4 This is a schematic diagram of the installation of the detection component of the utility model.

[0022] Figure 5 This is a schematic diagram of the installation of the first brush roller and the second brush roller of the utility model.

[0023] Figure 6 This is a schematic diagram of the installation of the comb plate and baffle of the utility model.

[0024] Figure 7 This is a schematic diagram of the internal structure of the fixed pipe of the utility model.

[0025] Notes on figure numbers: 11 main frame, 12 handle, 13 first running wheel, 14 second running wheel, 15 connecting support plate, 16 first transmission box, 17 second transmission box, 18 third conical friction wheel, 19 sleeve shaft, 20 external spline shaft, 21 motor, 22 threaded rod, 23 first brush roller, 24 second brush roller, 25 comb plate, 26 baffle plate, 27 protective plate, 28 limit plate, 29 return spring, 30 fixed tube, 31 detection component. DETAILED DESCRIPTION

[0026] In order to make the purpose, technical solutions and advantages of the present invention more clearly understood, the present invention is further described in detail below in conjunction with the accompanying drawings and embodiments.

[0027] Example 1

[0028] In one embodiment, Figure 1-Figure 7As shown, a power grid line monitoring device comprises a main frame 11, a handle 12 is fixedly provided on the upper end of the main frame 11, a first running wheel 13 and a second running wheel 14 are symmetrically provided inside the main frame 11, a connecting support plate 15 is rotatably provided between the rotating shafts on both sides of the two first running wheels 13 and the second running wheels 14, a first transmission box 16 and a second transmission box 17 are rotatably provided on the rotating shafts on both sides of the first running wheels 13 and the second running wheels 14, a driving assembly for driving the two first running wheels 13 and the second running wheels 14 to rotate is provided inside the first transmission box 16 and the second transmission box 17, and the two first transmission boxes 16 are fixedly provided at the inner bottom end of the main frame 11, A detection component 31 is fixedly provided between the two connecting support plates 15, a guide slide bar is symmetrically provided on one side of the second transmission box 17, a guide slide groove is provided at the inner upper end of the main frame 11 corresponding to the position of the guide slide bar, a threaded rod 22 is provided in the threaded hole on the upper end of the mounting block on one side of the second transmission box 17, a rotating block is rotatably provided at one end of the threaded rod 22, the rotating block is fixedly provided on one side of the first transmission box 16, the threaded rod 22 is rotatably provided in the mounting hole on the upper end of the main frame 11, a cleaning mechanism for cleaning the cables is provided inside one end of the main frame 11, and the cleaning mechanism facilitates the cleaning of the cables, thereby increasing the accuracy of the detection component 31 in monitoring the cables;

[0029] The driving assembly includes a motor 21, which is fixed in a mounting groove on one side of the main frame 11. The output end of the motor 21 is fixedly connected to a rotating shaft at one end of a first walking wheel 13. The first conical friction wheel on the rotating shaft of the first walking wheel 13 is frictionally matched with the second conical friction wheel at one end of the sleeve shaft 19. The sleeve shaft 19 is rotatably arranged in a mounting hole at the upper end of the first transmission box 16. An external spline shaft 20 is slidably provided at one end of the sleeve shaft 19. The external spline shaft 20 is connected to the sleeve shaft 19 through a spline fit. A third conical friction wheel 18 is fixedly provided at one end of the external spline shaft 20. A fourth conical friction wheel is frictionally arranged on the third conical friction wheel 18, and the fourth conical friction wheel is fixedly arranged on a rotating shaft at one end of a second traveling wheel 14, and the external spline shaft 20 is rotatably arranged in a mounting hole at the bottom end of the second transmission box 17, and a first driving wheel is fixedly arranged on a rotating shaft on one side of the first traveling wheel 13 and the second traveling wheel 14, and the first driving wheel is connected to the first driven wheel on the rotating shaft at one end of the other first traveling wheel 13 and the second traveling wheel 14 through a first belt. When in use, when it is necessary to monitor the cable, the user takes the main frame 11 by the handle 12, and moves the main frame 1 The cable is passed through the notch on one side of the cable, so that the cable is in close contact with the middle of the two first running wheels 13, and then the threaded rod 22 is rotated. Under the action of the thread, the two second transmission boxes 17 drive the two second running wheels 14 to move along the length direction of the guide slide bar. When the two second running wheels 14 are in close contact with the cable, the two first running wheels 13 and the second running wheels 14 can clamp the cable, so that the main frame 11 is fixed, and then the motor 21 is started. The output end of the motor 21 drives a first running wheel 13 to rotate, and the first running wheel 13 drives the external spline shaft through the cooperation of the first conical friction wheel and the second conical friction wheel. 20 rotates, the external spline shaft 20 drives a second travel wheel 14 to rotate through the third conical friction wheel 18 and the fourth conical friction wheel, and then the first travel wheel 13 and the second travel wheel 14 respectively drive another first travel wheel 13 and the second travel wheel 14 to rotate through the first belt, and the first travel wheel 13 and the second travel wheel 14 rotate in opposite directions, so that the main frame 11 moves along the length direction of the cable, and the line is monitored by two detection components 31, the detection component 31 is electrically connected to the external control component, and when the detection component 31 detects a problem, it can notify the staff to repair the cable.

[0030] The cleaning mechanism includes a first brush roller 23 and a second brush roller 24, each of which is provided with a plurality of bristles. The first brush roller 23 and the second brush roller 24 are respectively arranged at positions corresponding to the first walking wheel 13 and the second walking wheel 14 inside the main frame 11, and a first rotating plate and a second rotating plate are respectively rotatably provided on rotating columns at both ends of the first brush roller 23 and the second brush roller 24. The two first rotating plates are respectively fixed on one side of the two first transmission boxes 16, and the two second rotating plates are respectively fixed on one side of the two second transmission boxes 17. A second driven wheel and a third driven wheel are respectively fixed on the rotating shafts at one end of the first brush roller 23 and the second brush roller 24, and the second driven wheel and the third driven wheel are respectively connected to a second driving wheel on a rotating shaft on one side of the first walking wheel 13 and the second walking wheel 14 through a second belt and a third belt. The brush roller 23 and the brush roller 24 are connected to each other by transmission, and the first brush roller 23 and the brush roller 24 are connected to each other by transmission. The bottom end of the main frame 11 is provided with a rectangular through-hole at a position corresponding to the position of the first brush roller 23 and the second brush roller 24. When in use, when the first walking wheel 13 and the second walking wheel 14 rotate, the first walking wheel 13 and the second walking wheel 14 respectively drive the first brush roller 23 and the second brush roller 24 to rotate through the second belt and the third belt, and the second driving wheel and the third driving wheel are larger than the diameter of the second driven wheel and the third driven wheel, so that the rotation speed of the first brush roller 23 and the second brush roller 24 is greater than the rotation speed of the first walking wheel 13 and the second walking wheel 14. The first brush roller 23 and the second brush roller 24 clean the cable with a plurality of bristles, and then the detection component 31 monitors the cable. Since the first brush roller 23 and the second brush roller 24 are staggered, dust cleaned by the second brush roller 24 is prevented from falling on the first brush roller 23.

[0031] The first brush roller 23 and the second brush roller 24 are installed in a staggered manner. When in use, the first brush roller 23 and the second brush roller 24 are staggered to prevent dust cleaned by the second brush roller 24 from falling onto the first brush roller 23 .

[0032] Combing plates 25 are fixedly provided at positions corresponding to the first brush roller 23 and the second brush roller 24 inside the main frame 11. A plurality of combing grooves are provided on one side of the combing plate 25, which facilitates separation of residual dust inside the first brush roller 23 and the second brush roller 24 when in use.

[0033] A baffle 26 is fixedly provided on one side of the first transmission box 16 and the second transmission box 17 close to the comb plate 25, so as to prevent the dust cleaned by the first brush roller 23 and the second brush roller 24 from re-attaching to the cable when in use.

[0034] A plurality of balls are disposed on the inner side of the baffle plate 26 , which can prevent one side of the baffle plate 26 from damaging the cable when in use.

[0035] Example 2

[0036] The difference from Example 1 is that: a rotating seat is symmetrically provided on one side of the main frame 11, and a protective plate 27 is rotatably provided on the rotating seat. A limiting plate 28 is closely provided on one side of the protective plate 27. The limiting plate 28 is slidably provided inside the fixed tube 30. The fixed tube 30 is fixedly provided on one side of the main frame 11. A return spring 29 is fixedly provided between one end of the limiting plate 28 and one side inside the fixed tube 30. A dial plate is fixedly provided on the upper end of the limiting plate 28. A sliding groove is provided at the upper end of the fixed tube 30 corresponding to the position of the dial plate. When in use, when the main frame 1 Before working, the two protection plates 27 are rotated so that one side of the protection plates 27 is in close contact with one side of the main frame 11. At the same time, when the protection plates 27 are rotated, the limiting plates 28 are pushed to slide to the inside of the fixed tube 30. When one side of the protection plates 27 is in close contact with one side of the main frame 11, the limiting plates 28 are returned to the initial position under the action of the return spring 29, so that one side of the limiting plates 28 is in close contact with one side of the protection plates 27, thereby fixing the protection plates 27 to prevent the first running wheels 13 and the second running wheels 14 of the main frame 11 from being separated from the cable when the main frame 11 is in use, causing the main frame 11 to fall off.

[0037] The above embodiment discloses a power grid line monitoring device, wherein when it is necessary to monitor the cable, the user takes the main frame 11 through the handle 12, passes the cable through the notch on one side of the main frame 11, so that the cable is in close contact with the middle of the two first running wheels 13, and then rotates the threaded rod 22. Under the action of the thread, the two second transmission boxes 17 drive the two second running wheels 14 to move along the length direction of the guide slide bar. When the two second running wheels 14 are in close contact with the cable, the two first running wheels 13 and the second running wheels 14 can clamp the cable, thereby fixing the main frame 11, and rotating the two protective plates 27 so that one side of the protective plates 27 is in close contact with the main frame 11. One side is in close contact with the other side of the main frame 11, and when the protective plate 27 rotates, the limit plate 28 is pushed to slide to the inside of the fixed tube 30. When one side of the protective plate 27 is in close contact with one side of the main frame 11, the limit plate 28 returns to the initial position under the action of the return spring 29, so that one side of the limit plate 28 is in close contact with one side of the protective plate 27, thereby fixing the protective plate 27 to prevent the first running wheel 13 and the second running wheel 14 of the main frame 11 from being separated from the cable when in use, causing the main frame 11 to fall off, and then the motor 21 is started, and the output end of the motor 21 drives a first running wheel 13 to rotate, and the first running wheel 13 drives the outer spline shaft 2 through the cooperation of the first conical friction wheel and the second conical friction wheel. 0 rotates, the external spline shaft 20 drives a second travel wheel 14 to rotate through the third conical friction wheel 18 and the fourth conical friction wheel, and then the first travel wheel 13 and the second travel wheel 14 respectively drive another first travel wheel 13 and the second travel wheel 14 to rotate through the first belt, and the first travel wheel 13 and the second travel wheel 14 rotate in opposite directions, so that the main frame 11 moves along the length direction of the cable, and at the same time, when the first travel wheel 13 and the second travel wheel 14 rotate, a first travel wheel 13 and a second travel wheel 14 respectively drive the first brush roller 23 and the second brush roller 24 to rotate through the second belt and the third belt, and the second driving wheel and the third driving wheel are large. The diameter of the second driven wheel and the third driven wheel makes the rotation speed of the first brush roller 23 and the second brush roller 24 greater than the rotation speed of the first walking wheel 13 and the second walking wheel 14. The first brush roller 23 and the second brush roller 24 clean the cables through a plurality of bristles, and then the detection component 31 monitors the cables. Since the first brush roller 23 and the second brush roller 24 are staggered, dust cleaned by the second brush roller 24 is prevented from falling on the first brush roller 23, and the circuit is monitored by two detection components 31. The detection component 31 is electrically connected to the external control component. When the detection component 31 detects a problem, it can notify the staff to repair the cable.

[0038] The above is only a specific implementation of the present application, but the protection scope of the present application is not limited thereto. Any person skilled in the art who is familiar with the present technical field can easily think of changes or substitutions within the technical scope disclosed in the present application, which should be included in the protection scope of the present application. Therefore, the protection scope of the present application should be based on the protection scope of the claims.

Claims

1. A power grid line monitoring device, comprising a main frame (11), a handle (12) is fixedly provided at the upper end of the main frame (11), a first running wheel (13) and a second running wheel (14) are symmetrically provided inside the main frame (11), a connecting support plate (15) is rotatably provided between the rotating shafts on both sides of the two first running wheels (13) and the second running wheels (14), a first transmission box (16) and a second transmission box (17) are rotatably provided on the rotating shafts on both sides of the first running wheels (13) and the second running wheels (14), a driving assembly for driving the two first running wheels (13) and the second running wheels (14) to rotate is provided inside the first transmission box (16) and the second transmission box (17), characterized in that: The two first transmission boxes (16) are fixedly arranged at the bottom end of the inner side of the main frame (11), and a detection component (31) is fixedly arranged between the two connecting support plates (15). A guide slide bar is symmetrically arranged on one side of the second transmission box (17), and a guide slide groove is arranged at the inner upper end of the main frame (11) corresponding to the position of the guide slide bar. A threaded rod (22) is arranged in the threaded hole at the upper end of the mounting block on one side of the second transmission box (17), and a rotating block is rotatably arranged at one end of the threaded rod (22). The rotating block is fixedly arranged on one side of the first transmission box (16), and the threaded rod (22) is rotatably arranged in the mounting hole at the upper end of the main frame (11). A cleaning mechanism for cleaning cables is arranged inside one end of the main frame (11).

2. A power grid line monitoring device according to claim 1, characterized in that: The driving assembly comprises an electric motor (21), the electric motor (21) being fixedly arranged in a mounting groove on one side inside the main frame (11), the output end of the electric motor (21) being fixedly connected to a rotating shaft at one end of a first walking wheel (13), a first conical friction wheel on the rotating shaft of the first walking wheel (13) being frictionally matched with a second conical friction wheel at one end of a sleeve shaft (19), the sleeve shaft (19) being rotatably arranged in a mounting hole at the upper end of a first transmission box (16), an external spline shaft (20) being slidably arranged at one end of the sleeve shaft (19), the external spline shaft (20) being connected to the sleeve shaft (19) by spline matching, the external spline shaft (20) being frictionally matched with the sleeve shaft (19), A third conical friction wheel (18) is fixedly provided at one end of the key shaft (20), a fourth conical friction wheel is frictionally provided on the third conical friction wheel (18), the fourth conical friction wheel is fixedly provided on a rotating shaft at one end of a second traveling wheel (14), the external spline shaft (20) is rotatably provided in a mounting hole at the bottom end of a second transmission box (17), a first driving wheel is fixedly provided on a rotating shaft at one side of the first traveling wheel (13) and the second traveling wheel (14), the first driving wheel is transmission-connected to a first driven wheel on a rotating shaft at one end of another first traveling wheel (13) and the second traveling wheel (14) through a first belt.

3. A power grid line monitoring device according to claim 2, characterized in that: The cleaning mechanism comprises a first brush roller (23) and a second brush roller (24), each of which is provided with a plurality of bristles. The first brush roller (23) and the second brush roller (24) are respectively arranged inside the main frame (11) at positions corresponding to the positions of the first running wheel (13) and the second running wheel (14). A first rotating plate and a second rotating plate are respectively rotatably arranged on rotating columns at both ends of the first brush roller (23) and the second brush roller (24), and the two first rotating plates are respectively fixedly arranged on one side of two first transmission boxes (16). The two second rotating plates are respectively fixed on one side of the two second transmission boxes (17); a second driven wheel and a third driven wheel are respectively fixed on the rotating shafts at one end of the first brush roller (23) and the second brush roller (24); the second driven wheel and the third driven wheel are respectively connected to the second driving wheel and the third driving wheel on the rotating shafts at one side of the first walking wheel (13) and the second walking wheel (14) through a second belt and a third belt; a rectangular through hole is provided at the bottom end of the main frame (11) corresponding to the position of the first brush roller (23) and the second brush roller (24).

4. A power grid line monitoring device according to claim 3, characterized in that: The first brush roller (23) and the second brush roller (24) are installed in a staggered manner.

5. A power grid line monitoring device according to claim 3, characterized in that: Combing plates (25) are fixedly provided inside the main frame (11) at positions corresponding to the first brush roller (23) and the second brush roller (24), and a plurality of combing grooves are provided on one side of the combing plate (25).

6. A power grid line monitoring device according to claim 5, characterized in that: A baffle plate (26) is fixedly provided on one side of the first transmission box (16) and the second transmission box (17) close to the combing plate (25).

7. A power grid line monitoring device according to claim 6, characterized in that: A plurality of balls are arranged on the inner side of the baffle (26).

8. The power grid line monitoring device according to claim 1, characterized in that: A rotating seat is symmetrically arranged on one side of the main frame (11), and a protective plate (27) is rotatably arranged on the rotating seat. A limiting plate (28) is tightly arranged on one side of the protective plate (27), and the limiting plate (28) is slidably arranged inside a fixed tube (30). The fixed tube (30) is fixedly arranged on one side of the main frame (11), and a return spring (29) is fixedly arranged between one end of the limiting plate (28) and one side inside the fixed tube (30). A shifting plate is fixedly arranged on the upper end of the limiting plate (28), and a sliding groove is arranged at the upper end of the fixed tube (30) corresponding to the position of the shifting plate.

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