A multi-functional testing device for wind turbine operation and maintenance

Abstract

This invention discloses a multi-functional inspection device for wind turbine operation and maintenance, relating to the field of wind turbine operation and maintenance technology. It includes a clamp, with a vertical plate fixedly connected to the outer side of the clamp. A top plate is fixedly connected to the upper side of the vertical plate. An operation and maintenance unit is arranged below the top plate. The operation and maintenance unit includes a U-shaped frame positioned below the top plate. A cleaning component is arranged on the inner side of the U-shaped frame. The cleaning component is used to clean impurities on the surface of the nacelle in the wind turbine, facilitating clearer operation and maintenance inspections. This multi-functional inspection device for wind turbine operation and maintenance, through the inclusion of a clamp, vertical plate, fixed plate, U-shaped frame, high-definition cameras, guide rails, and casters, facilitates the control of multiple high-definition cameras to inspect the surface of the wind turbine nacelle. Furthermore, through side rods, scraper blades one and two, a rotating shaft, a threaded cylinder, and a screw, it facilitates the control of scraper blades one and two to clean impurities on multiple surfaces of the nacelle, aiding subsequent inspections.

Description

Technical Field

[0001] This invention relates to the field of wind turbine operation and maintenance technology, specifically a multi-functional testing device for wind turbine operation and maintenance. Background Technology

[0002] A wind turbine is a device that converts wind energy into electrical energy and is an important component of renewable energy technology. During routine maintenance, wind turbine surfaces require inspection using maintenance and testing equipment.

[0003] A search revealed Chinese patent application number "CN202410262028.6", which specifically describes a multifunctional testing device and method for the operation and maintenance of wind turbine towers. The wind turbine includes a tower, a nacelle, and blades, with the nacelle and blades mounted on the tower. The testing device includes: an upper guide rail positioned above the tower; a first drive and limit module mounted on the upper guide rail and moving along the circumference of the tower; a lower guide rail positioned at the bottom of the tower; a second drive and limit module mounted on the lower guide rail and moving along the circumference of the tower; a third drive and transmission module mounted between the upper and lower guide rails and moving along the height of the tower; and a control module connected to the first, second, and third drive and transmission modules.

[0004] The aforementioned patent describes a wind turbine that includes a tower, nacelle, and blades. During operation and maintenance, the surface of the nacelle needs to be inspected. High-definition cameras are often used to observe the nacelle surface during inspection. However, since the nacelle is located at high altitude, bird droppings and dust accumulate on its surface. These bird droppings and impurities can cover up damaged and corroded areas of the nacelle, resulting in poor nacelle operation and maintenance. Summary of the Invention

[0005] To address the shortcomings of existing technologies, this invention provides a multi-functional testing device for wind turbine operation and maintenance, which solves the problem that impurities easily accumulate on the surface of the nacelle, affecting the operation and maintenance results.

[0006] To achieve the above objectives, the present invention provides the following technical solution:

[0007] A multi-functional inspection device for wind turbine operation and maintenance includes a clamp, a vertical plate fixedly connected to the outer side of the clamp, a top plate fixedly connected to the upper side of the vertical plate, an operation and maintenance unit disposed below the top plate, the operation and maintenance unit including a U-shaped frame disposed below the top plate, multiple mounting blocks II fixedly connected to the front side of the U-shaped frame, high-definition cameras fixedly connected to the outer sides of each of the multiple mounting blocks II, and a cleaning component disposed on the inner side of the U-shaped frame. The cleaning component is used to clean impurities on the surface of the nacelle in the wind turbine, making operation and maintenance inspections clearer.

[0008] Preferably, a guide rail is fixedly connected to the lower side of the top plate, side blocks are fixedly connected to both the left and right sides of the U-shaped frame, a fixing plate is fixedly connected to the upper side of the side blocks, a plurality of mounting blocks are fixedly connected to the upper side of the fixing plate, a control rod is rotatably connected between two mounting blocks, a moving wheel is fixedly connected to the outer side of the control rod, a motor for driving the control rod to rotate is fixedly connected to the outer side of the mounting block, the moving wheel is adapted to the guide rail, a sliding groove is opened on the upper side of the top plate, a slider is slidably connected to the inner side of the sliding groove, and a support block is fixedly connected between the slider and the U-shaped frame.

[0009] Preferably, the cleaning assembly includes side rods, which are disposed on the left and right sides of the U-shaped frame. One end of each side rod is fixedly connected to a scraper, and the other end of each side rod passes through the outside of the U-shaped frame and is fixedly connected to a side plate. A rotating shaft is rotatably connected to the upper side of the U-shaped frame, and a turntable is fixedly connected to the upper end of the rotating shaft. Two control blocks are connected to the outer side of the turntable, and inclined plates are rotatably connected to the upper side of each of the two control blocks. A rotating block is fixedly connected to the outer side of each of the two side plates, and the inclined plates and rotating blocks are rotatably connected.

[0010] Preferably, the upper side of the U-shaped frame is provided with a moving groove, the inner side of the moving groove is slidably connected to a moving block, the upper side of the moving block is fixedly connected to a stabilizing block, the outer side of the stabilizing block is fixedly connected to a toothed plate, the outer side of the rotating shaft is fixedly connected to a gear that meshes with the toothed plate, and an electric push rod is fixedly connected between the outer side of the moving block and the inner wall of the moving groove.

[0011] Preferably, a telescopic rod is fixedly connected to the lower side of the U-shaped frame, a scraper is fixedly connected to the lower end of the telescopic rod, a screw is rotatably connected to the upper side of the scraper, and a threaded cylinder is fixedly connected to the lower end of the rotating shaft, with the threaded cylinder threadedly connected to the screw.

[0012] Preferably, the scraper blade 2 has a rectangular hole in the middle, and two fixing blocks are fixedly connected to the front and rear sides of the rectangular hole. A reciprocating groove is formed on the outer side of the fixing block, and a reciprocating block is slidably connected to the outer side of the reciprocating groove. A vibrating plate is fixedly connected to the lower side of the reciprocating block, and control block 2 is fixedly connected to the upper side of the reciprocating block on both the front and rear sides. Two trapezoidal blocks are arranged inside the rectangular hole. A stop rod is fixedly connected to the side of control block 2 near the trapezoidal block. A connecting rod is fixedly connected between the two trapezoidal blocks. A reciprocating rod is fixedly connected to the left side of one of the trapezoidal blocks. A contact block is fixedly connected to the outer end of the reciprocating rod. A spring 1 is fixedly connected between the contact block and scraper blade 2. A spring 2 is fixedly connected between the outer side of the reciprocating block and the inner wall of the reciprocating groove.

[0013] Preferably, a limiting block is fixedly connected to the upper side of the U-shaped frame, a rotating rod is rotatably connected to the outer side of the limiting block, a gear two is fixedly connected to the upper end of the rotating rod, a cam is fixedly connected to the lower end of the rotating rod through the lower side of the limiting block, the cam abuts against the contact block, a bottom rod is fixedly connected to the lower side of the top plate, and a toothed plate one that meshes with the gear two is fixedly connected to the lower end of the bottom rod.

[0014] Beneficial effects

[0015] This invention provides a multifunctional testing device for the operation and maintenance of wind turbine units. Compared with the prior art, it has the following advantages:

[0016] (1) The multi-functional testing device for wind turbine operation and maintenance is equipped with clamps, upright plates, fixed plates, U-shaped frames, high-definition cameras, guide rails and moving wheels. It is convenient to control multiple high-definition cameras to inspect the surface of the nacelle of the wind turbine. It is also convenient to control scraper one and scraper two to clean impurities on multiple surfaces of the nacelle through side rods, scraper one, scraper two, rotating shaft, threaded cylinder and screw, which facilitates subsequent testing.

[0017] (2) The multi-functional detection device for the operation and maintenance of the wind turbine is equipped with a scraper, a vibrating plate, a trapezoidal block, a contact block and a cam. When the scraper and scraper clean the impurities on the surface of the nacelle, the vibrating plate moves repeatedly to increase the cleaning effect. Attached Figure Description

[0018] Figure 1 This is a three-dimensional structural diagram of the present invention;

[0019] Figure 2 The figure shown is a bottom-view three-dimensional structural diagram of the present invention with the operation and maintenance unit removed;

[0020] Figure 3 This is a three-dimensional structural diagram of the operation and maintenance unit in this invention;

[0021] Figure 4 This is a three-dimensional structural diagram of the operation and maintenance unit in this invention from another perspective;

[0022] Figure 5 for Figure 4 Enlarged view of point A in the middle;

[0023] Figure 6 This is a top-view three-dimensional structural diagram of the operation and maintenance unit in this invention;

[0024] Figure 7 This is a three-dimensional structural diagram of the cleaning component in this invention;

[0025] Figure 8 for Figure 7 Enlarged view of point B in the middle;

[0026] Figure 9 This is a cross-sectional perspective view of the cleaning component in this invention;

[0027] Figure 10 for Figure 9 A magnified view of point C in the middle.

[0028] In the diagram: 1. Clamp; 2. Vertical plate; 3. Top plate; 4. Maintenance unit; 5. Slide groove; 6. Slider; 7. Support block; 8. Base rod; 9. Toothed plate one; 10. Guide rail; 41. U-shaped frame; 42. Side block; 43. Fixing plate; 44. Mounting block one; 45. Control rod; 46. Moving wheel; 47. Motor; 48. Cleaning assembly; 49. Mounting block two; 410. High-definition camera; 481. Side rod; 482. Scraper one; 483. Side plate; 484. Rotating shaft; 485. Turntable; 486. Control block one; 487. Inclined plate; 488. Rotating block; 489. Gear one; 4810. Moving groove; 4811. Moving wheel 4812. Stabilizing block; 4813. Toothed plate II; 4814. Electric push rod; 4815. Telescopic rod; 4816. Scraper II; 4817. Threaded cylinder; 4818. Screw; 4819. Rectangular hole; 4820. Fixing block; 4821. Reciprocating groove; 4822. Reciprocating block; 4823. Vibrating plate; 4824. Control block II; 4825. Push rod; 4826. Limiting block; 4827. Rotating rod; 4828. Gear II; 4829. Cam; 4830. Trapezoidal block; 4831. Connecting rod; 4832. Reciprocating rod; 4833. Contact block; 4834. Spring I; 4835. Spring II. Detailed Implementation

[0029] 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.

[0030] This invention provides the following technical solutions: Example 1

[0031] Please see Figures 1-6A multi-functional inspection device for wind turbine operation and maintenance includes a clamp 1, a vertical plate 2 fixedly connected to the outer side of the clamp 1, a top plate 3 fixedly connected to the upper side of the vertical plate 2, an operation and maintenance unit 4 set below the top plate 3, the operation and maintenance unit 4 including a U-shaped frame 41, the U-shaped frame 41 set below the top plate 3, multiple mounting blocks 49 fixedly connected to the front side of the U-shaped frame 41, high-definition cameras 410 fixedly connected to the outer side of each of the multiple mounting blocks 49, and a cleaning component 48 set on the inner side of the U-shaped frame 41. The cleaning component 48 is used to clean impurities on the surface of the nacelle in the wind turbine, making operation and maintenance inspection clearer. The clamp 1 is connected to the tower on the wind turbine, making it easy to install the device on the wind turbine. The top plate 3 is located above the nacelle, making it easy for the operation and maintenance unit 4 to inspect the nacelle surface and facilitate daily maintenance.

[0032] A guide rail 10 is fixedly connected to the lower side of the top plate 3. Side blocks 42 are fixedly connected to both sides of the U-shaped frame 41. A fixing plate 43 is fixedly connected to the upper side of the side blocks 42. Multiple mounting blocks 44 are fixedly connected to the upper side of the fixing plate 43. A control rod 45 is rotatably connected between two mounting blocks 44. A moving wheel 46 is fixedly connected to the outer side of the control rod 45. A motor 47 that drives the control rod 45 to rotate is fixedly connected to the outer side of the mounting blocks 44. The moving wheel 46 is adapted to the guide rail 10. A sliding groove 5 is opened on the upper side of the top plate 3. A slider 6 is slidably connected to the inner side of the sliding groove 5. A support block 7 is fixedly connected between the slider 6 and the U-shaped frame 41. When testing, the motor 47 is started. The motor 47 drives the control rod 45 to rotate. The control rod 45 drives the moving wheel 46 to move. The moving wheel 46 drives the fixing plate 43 to move. The fixing plate 43 drives the U-shaped frame 41 to move back and forth, which facilitates the cleaning of impurities on the surface of the cabin and the testing.

[0033] The cleaning component 48 includes side rods 481, which are arranged on the left and right sides of the U-shaped frame 41. One end of each side rod 481 is fixedly connected to a scraper 482. The other end of each side rod 481 passes through the outside of the U-shaped frame 41 and is fixedly connected to a side plate 483. A rotating shaft 484 is rotatably connected to the upper side of the U-shaped frame 41. A turntable 485 is fixedly connected to the upper end of the rotating shaft 484. Two control blocks 486 are connected to the outer side of the turntable 485. An inclined plate 487 is rotatably connected to the upper side of each of the two control blocks 486. The outer side of the two side plates 483... A rotating block 488 is fixedly connected to the side, and an inclined plate 487 is rotatably connected to the rotating block 488. A moving groove 4810 is opened on the upper side of the U-shaped frame 41. A moving block 4811 is slidably connected to the inner side of the moving groove 4810. A stabilizing block 4812 is fixedly connected to the upper side of the moving block 4811. A toothed plate 4813 is fixedly connected to the outer side of the stabilizing block 4812. A gear 489 that meshes with the toothed plate 4813 is fixedly connected to the outer side of the rotating shaft 484. An electric push is fixedly connected between the outer side of the moving block 4811 and the inner wall of the moving groove 4810. Before inspecting the surface of the engine room, lever 4814 controls the electric push rod 4814 to move the moving block 4811. The moving block 4811 moves the stabilizing block 4812, which in turn moves the gear plate 4813. Since the gear plate 4813 meshes with gear 489, it causes gear 4813 to rotate, which in turn rotates shaft 484. Shaft 484 then rotates turntable 485, which in turn rotates control block 486. Control block 486 then rotates inclined plate 487. The rotation, due to the parallel arrangement of the two inclined plates 487, causes the inclined plates 487 to drive the side plates 483 to move. The side plates 483 on both sides move closer to each other, and the side plates 483 drive the side rods 481 to move. The side rods 481 drive the scrapers 482 to move. The two scrapers 482 move closer to the cabin and contact the left and right sides of the cabin. This facilitates the control of the scrapers 482 to move back and forth when the U-shaped frame 41 moves back and forth. This makes it easier for the scrapers 482 to clean the dust and impurities on the left and right sides of the cabin, and facilitates the high-definition camera 410 to inspect the surface of the cabin.

[0034] A telescopic rod 4815 is fixedly connected to the lower side of the U-shaped frame 41. A scraper 4816 is fixedly connected to the lower end of the telescopic rod 4815. A screw 4818 is rotatably connected to the upper side of the scraper 4816. A threaded cylinder 4817 is fixedly connected to the lower end of the rotating shaft 484. The threaded cylinder 4817 is threadedly connected to the screw 4818. When the scraper 482 cleans impurities on the surface of the engine room, the rotating shaft 484 rotates, causing the threaded cylinder 4817 to rotate. Since the threaded cylinder 4817 is threadedly connected to the screw 4818, the screw 4818 causes the scraper 4816 to descend, making it easier for the scraper 4816 to contact the top of the engine room and clean the dust and impurities on the top of the engine room. Example 2

[0035] Based on Example 1, such as Figures 7-10 As shown, a rectangular hole 4819 is provided in the middle of scraper 4816. Two fixing blocks 4820 are fixedly connected to both the front and rear sides of the rectangular hole 4819. A reciprocating groove 4821 is provided on the outer side of the fixing block 4820. A reciprocating block 4822 is slidably connected to the outer side of the reciprocating groove 4821. A vibrating plate 4823 is fixedly connected to the lower side of the reciprocating block 4822. A control block 4824 is fixedly connected to the upper side of the reciprocating blocks 4822 on both the front and rear sides. Two trapezoidal blocks 4830 are provided inside the rectangular hole 4819. The side of the control block 4824 closest to the trapezoidal blocks 4830 is fixedly connected to... There is a stop rod 4825, and a connecting rod 4831 is fixedly connected between two trapezoidal blocks 4830. A reciprocating rod 4832 is fixedly connected to the left side of one of the trapezoidal blocks 4830. A contact block 4833 is fixedly connected to the outer end of the reciprocating rod 4832. A spring 4834 is fixedly connected between the contact block 4833 and the scraper 4816. A spring 4835 is fixedly connected between the outer side of the reciprocating block 4822 and the inner wall of the reciprocating groove 4821. A limit block 4826 is fixedly connected to the upper side of the U-shaped frame 41. A rotating rod 4827 is rotatably connected to the outer side of the limit block 4826. Gear 4828 is fixedly connected to the upper end of the top plate 7. A cam 4829 is fixedly connected to the lower end of the rotating rod 4827, passing through the lower side of the limiting block 4826. The cam 4829 abuts against the contact block 4833. A base rod 8 is fixedly connected to the lower side of the top plate 3. A toothed plate 9, meshing with gear 4828, is fixedly connected to the lower end of the base rod 8. When cleaning impurities from the surface of the engine room, scraper 4816 drives gear 4828 to move. Because gear 4828 meshes with toothed plate 9, gear 4828 rotates, causing rotating rod 4827 to rotate. 4827 drives cam 4829 to rotate, cam 4829 drives contact block 4833 to move left and right, contact block 4833 drives reciprocating rod 4832 to move left and right, reciprocating rod 4832 drives trapezoidal block 4830 to move left and right repeatedly, trapezoidal block 4830 drives push rod 4825 to move, push rod 4825 drives control block 4824 to move, control block 4824 drives reciprocating block 4822 to move, reciprocating block 4822 drives vibrating plate 4823 to move back and forth repeatedly, so that vibrating plate 4823 contacts the engine compartment, thereby increasing the cleaning effect of vibrating plate 4823 on the surface of the engine compartment.

[0036] Working principle: In use, the operator first connects clamp 1 to the tower of the wind turbine, then controls motor 47 to drive moving wheel 46 to move, facilitating the movement of scraper blades 482 and 4816 around the nacelle. Then, the electric push rod 4814 drives moving block 4811. Under the action of toothed plate 4813, gear 489, rotating shaft 484, turntable 485, control block 486, inclined plate 487, side plate 483, and side rod 481, scraper blade 482 moves, and the scraper blades 482 on both sides contact the nacelle, facilitating the cleaning of dust and impurities on the left and right sides of the nacelle. Simultaneously, rotating shaft 4... 84 drives the threaded cylinder 4817 to rotate, and under the action of the screw 4818, controls the scraper 4816 to descend, facilitating the cleaning of dust on the top of the engine compartment. When inspection is carried out, the motor 47 is started to control the movement of scraper 482 and scraper 4816, and the surface of the engine compartment is inspected by the high-definition camera 410, which facilitates operation and maintenance. Under the action of toothed plate 9, U-shaped frame 41 drives gear 4828 to rotate. Under the action of rotating rod 4827, cam 4829, reciprocating rod 4832, trapezoidal block 4830, and stop rod 4825, the vibrating plate 4823 is controlled to move back and forth repeatedly, increasing the cleaning effect of dust and impurities.

[0037] It should be noted that, in this document, relational terms such as "first" and "second" are used only to distinguish one entity or operation from another, and do not necessarily require or imply any such actual relationship or order between these entities or operations. Furthermore, the terms "comprising," "including," or any other variations thereof are intended to cover non-exclusive inclusion, such that a process, method, article, or apparatus that comprises a list of elements includes not only those elements but also other elements not expressly listed, or elements inherent to such process, method, article, or apparatus.

[0038] Although embodiments of the invention have been shown and described, it will be understood by those skilled in the art that various changes, modifications, substitutions and alterations can be made to these embodiments without departing from the principles and spirit of the invention, the scope of which is defined by the appended claims and their equivalents.

Claims

1. A multi-functional testing device for wind turbine operation and maintenance, comprising a clamp (1), characterized in that: A vertical plate (2) is fixedly connected to the outside of the clamp (1), and a top plate (3) is fixedly connected to the upper side of the vertical plate (2). An operation and maintenance unit (4) is set below the top plate (3). The operation and maintenance unit (4) includes a U-shaped frame (41). The U-shaped frame (41) is set below the top plate (3). Multiple mounting blocks (49) are fixedly connected to the front side of the U-shaped frame (41). High-definition cameras (410) are fixedly connected to the outer side of the multiple mounting blocks (49). A cleaning component (48) is set on the inner side of the U-shaped frame (41). The cleaning component (48) is used to clean impurities on the surface of the nacelle in the wind turbine. The top plate (3) is fixedly connected to the lower side of the guide rail (10), and the U-shaped frame (41) is fixedly connected to the left and right sides of the side blocks (42). The side blocks (42) are fixedly connected to the upper side of the fixed plate (43), and the upper side of the fixed plate (43) is fixedly connected to multiple mounting blocks (44). A control rod (45) is rotatably connected between two mounting blocks (44). A moving wheel (46) is fixedly connected to the outer side of the control rod (45). A motor (47) that drives the control rod (45) to rotate is fixedly connected to the outer side of the mounting block (44). The moving wheel (46) is adapted to the guide rail (10). A sliding groove (5) is opened on the upper side of the top plate (3). A slider (6) is slidably connected to the inner side of the sliding groove (5). A support block (7) is fixedly connected between the slider (6) and the U-shaped frame (41). The cleaning assembly (48) includes side rods (481), which are arranged on the left and right sides of the U-shaped frame (41). One end of each side rod (481) is fixedly connected to a scraper (482), and the other end of each side rod (481) passes through the outside of the U-shaped frame (41) and is fixedly connected to a side plate (483). A rotating shaft (484) is rotatably connected to the upper side of the U-shaped frame (41), and a turntable (485) is fixedly connected to the upper end of the rotating shaft (484). Two control blocks (486) are connected to the outside of the turntable (485), and inclined plates (487) are rotatably connected to the upper side of each of the two control blocks (486). A rotating block (488) is fixedly connected to the outside of each of the two side plates (483), and the inclined plate (487) is rotatably connected to the rotating block (488).

2. The multi-functional testing device for wind turbine operation and maintenance according to claim 1, characterized in that: The upper side of the U-shaped frame (41) is provided with a moving groove (4810), the inner side of the moving groove (4810) is slidably connected to a moving block (4811), the upper side of the moving block (4811) is fixedly connected to a stabilizing block (4812), the outer side of the stabilizing block (4812) is fixedly connected to a toothed plate (4813), the outer side of the rotating shaft (484) is fixedly connected to a gear (489) that meshes with the toothed plate (4813), and an electric push rod (4814) is fixedly connected between the outer side of the moving block (4811) and the inner wall of the moving groove (4810).

3. The multi-functional testing device for wind turbine operation and maintenance according to claim 2, characterized in that: A telescopic rod (4815) is fixedly connected to the lower side of the U-shaped frame (41). A scraper (4816) is fixedly connected to the lower end of the telescopic rod (4815). A screw (4818) is rotatably connected to the upper side of the scraper (4816). A threaded cylinder (4817) is fixedly connected to the lower end of the rotating shaft (484). The threaded cylinder (4817) is threadedly connected to the screw (4818).

4. A multi-functional testing device for wind turbine operation and maintenance according to claim 3, characterized in that: The scraper (4816) has a rectangular hole (4819) in the middle. Two fixing blocks (4820) are fixedly connected to both the front and rear sides of the rectangular hole (4819). A reciprocating groove (4821) is provided on the outer side of each fixing block (4820). A reciprocating block (4822) is slidably connected to the outer side of the reciprocating groove (4821). A vibrating plate (4823) is fixedly connected to the lower side of the reciprocating block (4822). Control block (4824) is fixedly connected to the upper side of each reciprocating block (4822) on both the front and rear sides. Two trapezoidal blocks (4830) are provided inside the rectangular hole (4819). A stop rod (4825) is fixedly connected to the side of the control block 2 (4824) near the trapezoidal block (4830). A connecting rod (4831) is fixedly connected between the two trapezoidal blocks (4830). A reciprocating rod (4832) is fixedly connected to the left side of one of the trapezoidal blocks (4830). A contact block (4833) is fixedly connected to the outer end of the reciprocating rod (4832). A spring 1 (4834) is fixedly connected between the contact block (4833) and scraper 2 (4816). A spring 2 (4835) is fixedly connected between the outer side of the reciprocating block (4822) and the inner wall of the reciprocating groove (4821).

5. A multi-functional testing device for wind turbine operation and maintenance according to claim 4, characterized in that: A limiting block (4826) is fixedly connected to the upper side of the U-shaped frame (41). A rotating rod (4827) is rotatably connected to the outer side of the limiting block (4826). A gear two (4828) is fixedly connected to the upper end of the rotating rod (4827). A cam (4829) is fixedly connected to the lower side of the limiting block (4826) through the lower side of the rotating rod (4827). The cam (4829) abuts against the contact block (4833). A bottom rod (8) is fixedly connected to the lower side of the top plate (3). A toothed plate one (9) that meshes with the gear two (4828) is fixedly connected to the lower end of the bottom rod (8).

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