Battery disassembly overturning platform

By designing a battery disassembly and flipping platform, and utilizing load-bearing positioning, lifting and flipping components, the platform enables multi-angle flipping and height adjustment of batteries, solving the problem of low disassembly efficiency for large waste batteries and improving disassembly efficiency and safety.

CN223842945UActive Publication Date: 2026-01-27HUNAN ZHONGXIAN INTELLIGENT TECH CO LTD
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Patent Information

Application Number
CN202422869870.4
Authority / Receiving Office
CN · China
Patent Type
Utility models(China)
Current Assignee / Owner
Filing Date
2024-11-25
Publication Date
2026-01-27
Estimated Expiration
2034-11-25

AI Technical Summary

Technical Problem

The lack of standardized battery shapes during the recycling process of large-scale waste batteries leads to low efficiency and safety hazards due to manual flipping and disassembly, making them unsuitable for mass production.

Method used

A battery disassembly and flipping platform was designed. By combining a load-bearing positioning component, a lifting component, and a flipping component, the platform enables the positioning, lifting, and flipping of the battery. Utilizing a servo motor and chain drive system, the platform allows for multi-angle flipping and height adjustment of the battery, improving the convenience and safety of disassembly.

Benefits of technology

It improves battery disassembly efficiency, reduces labor intensity, enhances the adaptability and safety of the device, and adapts to the positioning and flipping requirements of different battery models.

✦ Generated by Eureka AI based on patent content.

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Abstract

The utility model relates to the technical field of battery disassembly, in particular to a battery disassembly overturning platform which comprises a base, supports are fixedly connected to the two ends of the base, and the tops of the two supports are fixedly connected through a connecting rod. A bearing positioning assembly is arranged on the upper side of the base. First guide rails are fixed to the two sides of an inner cavity of the support, an overturning assembly is slidably installed between the two first guide rails on the same side, and the two ends of the bearing and positioning assembly are rotationally connected with the two overturning assemblies correspondingly. A lifting assembly is installed between the two first guide rails, and the connecting end of the lifting assembly is connected with the overturning assembly. Batteries are positioned through the bearing and positioning assembly, the batteries of multiple models and different boundary dimensions can be positioned and overturned, the batteries are driven to ascend and descend through the lifting assembly, the bearing and positioning assembly is driven to overturn through the overturning assembly, rotation of different angles can be achieved, and convenience of later-period disassembly operation is facilitated; and therefore, the efficiency of disassembling the waste batteries by workers can be improved.
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Description

Technical Field

[0001] This utility model relates to the field of battery disassembly technology, specifically a battery disassembly flipping platform. Background Technology

[0002] A crucial step in the recycling of large used batteries is safe dismantling. Large batteries have connecting screws on their top, bottom, and sides. Since battery shapes vary widely in the market, there is no standardized method. Currently, most recycling companies rely on manual flipping to remove these screws and dismantle the batteries. This method is inefficient, poses numerous safety hazards, and is unsuitable for mass production. Therefore, we propose a battery dismantling and flipping platform. Utility Model Content

[0003] The purpose of this invention is to provide a battery disassembly and flipping platform, which solves the problems mentioned in the background art.

[0004] To achieve the above objectives, this utility model provides the following technical solution: a battery disassembly and flipping platform, including a base, with brackets fixedly connected to both ends of the base, and the tops of the two brackets fixedly connected by a connecting rod;

[0005] A load-bearing positioning component is provided on the upper side of the base;

[0006] Both sides of the inner cavity of the bracket are fixed with first guide rails, and a flipping component is slidably installed between the two first guide rails on the same side. The two ends of the bearing positioning component are respectively rotatably connected to the two flipping components.

[0007] A lifting assembly is installed between the two first guide rails, and the connecting end of the lifting assembly is connected to the tilting assembly.

[0008] By adopting the above technical solution, the battery is first placed on the load-bearing positioning component, and then positioned using the load-bearing positioning component. Then, the lifting component drives the flipping component and the load-bearing positioning component to lift the battery to a certain height, making it convenient for workers to disassemble its surface. At the same time, during the disassembly process, the flipping component can drive the load-bearing positioning component to flip, allowing the battery to rotate at different angles, which further improves the convenience of the disassembly operation for workers and reduces their labor intensity.

[0009] In a preferred embodiment of this utility model, the bearing positioning component includes:

[0010] The main beam has connecting shafts fixed at both ends, and the connecting shafts are connected to the corresponding flipping components.

[0011] There are two crossbeams, which are distributed on both sides of the bottom of the main beam. The two side walls of the main beam are fixed with slide rails. The outer wall of the slide rail is fitted with a matching first slider. The outer wall of the first slider is fixedly connected to the crossbeam through a connecting plate.

[0012] Two pressure rods are distributed directly above the two crossbeams. Each pressure rod has a first lead screw slider rotatably mounted on both ends. A turntable is fixedly fitted on the outer wall of the first lead screw slider. A matching first lead screw is connected through the inner cavity of the first lead screw slider. The tail end of the first lead screw is rotatably connected to the top end of the crossbeam.

[0013] The first positioning plate, there are two first positioning plates, the two first positioning plates are distributed at both ends of one side wall of the main beam, and a second slider is fixed on one side wall of the first positioning plate, the second slider is slidably fitted on the slide rail;

[0014] The second positioning plate, there are four of them, and they are distributed at both ends of one side wall of the two crossbeams. A second lead screw slider is fixedly connected to one side wall of the second positioning plate. The second lead screw slider is fitted onto the outer wall of the matching second lead screw. Bearings are fitted at both ends of the second lead screw and the bearings are fixedly connected to one side wall of the crossbeam. A handle is fixed to one end of the second lead screw.

[0015] Positioning bolts are threaded through the outer walls of the first positioning plate and the connecting plate. Fixing strips are fixed on both sides of the main beam, and multiple evenly distributed threaded holes are opened on the fixing strips.

[0016] By adopting the above technical solution, after the battery is hoisted onto the main beam, the first positioning plate is first slidably adjusted to the optimal position, and the position of the pressure rod is adjusted by sliding the crossbeam. Then, the positioning bolts and corresponding threaded holes are engaged for positioning. Then, the turntable is rotated to drive the first lead screw slider to rotate, thereby causing the pressure rod to descend and press the pressure rod onto the upper surface of the battery for positioning. Then, the handle is rotated to drive the second lead screw to rotate, thereby driving the second lead screw slider to move, which in turn drives the second positioning plate to move and fit against the side wall in the width direction of the battery, thereby achieving repositioning and ensuring the stability of the battery after positioning.

[0017] In a preferred embodiment of this utility model, the flipping component includes:

[0018] The carrier has first guide wheels rotatably mounted on all four sides of its two side walls, and second guide wheels rotatably mounted on both sides of its top and bottom. The first and second guide wheels are in contact with the outer walls of the first guide rails and the side walls on both sides of the inner cavity of the support. The carrier is connected to the corresponding lifting assembly.

[0019] The connecting shaft and the corresponding carrier are rotatably connected. A servo motor is fixed to the outer wall of one of the carriers. The outer end of the drive shaft of the servo motor passes through the carrier and is fixedly connected to one of the connecting shafts.

[0020] By adopting the above technical solution, the servo motor can drive the corresponding connecting shaft to rotate, thereby enabling the entire load-bearing positioning component to rotate, thus achieving flipping and adjusting the rotation angle, facilitating disassembly operations by staff.

[0021] In a preferred embodiment of this utility model, the lifting assembly includes:

[0022] A drive motor is mounted on the top of the base, and both ends of the drive motor are fixedly connected to a rotating shaft;

[0023] The sprockets are eight in number, with four distributed at the outer end of each shaft. The four sprockets on the same side are arranged in a U-shape. The sprockets are rotatably connected to the inner wall of the bracket via a wheel frame. A chain is wound around the outer wall of the four sprockets on the same side. The two ends of the chain are fixedly connected to the top and bottom of the frame, respectively. The outer end of the shaft is fixedly connected to the corresponding sprocket.

[0024] By adopting the above technical solution, the drive motor drives the rotating shaft to rotate, thereby driving one of the sprockets to rotate. Under the chain drive, the carrier frame can be raised and lowered, thereby raising and lowering the load-bearing positioning component and the battery, so that the battery is at the optimal height for convenient operation.

[0025] In a preferred embodiment of this utility model, a tension sprocket is rotatably mounted on the inner side wall of the bracket, and the lower side of the chain meshes with the tension sprocket.

[0026] In a preferred embodiment of this utility model, a counterweight is fixedly fitted on the outer wall of the chain, which makes the chain highly stable during up-and-down movement.

[0027] In a preferred embodiment of this utility model, a carrier plate is fixed on both sides of the outer wall of the counterweight, a through hole is provided at the top center of the carrier plate, and a third guide wheel is rotatably installed on all four sides of one side wall of the carrier plate near the through hole. A second guide rail is fixed in the inner cavity of the bracket, the second guide rail passes through the through hole, and the third guide wheel is attached to the outer wall of the second guide rail.

[0028] By adopting the above technical solution, the stability of the counterweight lifting and lowering can be improved by using the third guide wheel to roll along the outer wall of the second guide rail.

[0029] Compared with the prior art, the beneficial effects of this utility model are as follows:

[0030] The present application provides a battery disassembly and flipping platform, which positions the battery using a bearing and positioning component, then uses a lifting component to lift the battery, and uses a flipping component to flip the bearing and positioning component, thereby enabling rotation at different angles. This facilitates the subsequent disassembly operation, improves the efficiency of workers in disassembling used batteries, and also saves manpower.

[0031] The pressure rod, the first positioning plate, and the second positioning plate allow for quick position adjustment, enabling the bearing positioning component to adapt to batteries of different sizes for proper positioning. This improves the adaptability of the device, allowing it to be compatible with multiple models of batteries of different shapes and sizes for positioning and flipping. It also ensures the stability of battery positioning, thereby enhancing the safety of flipping. Attached Figure Description

[0032] Other features, objects, and advantages of this invention will become more apparent from the following detailed description of non-limiting embodiments with reference to the accompanying drawings:

[0033] Figure 1 This is a schematic diagram of the overall structure of a battery disassembly and flipping platform according to the present invention;

[0034] Figure 2 This is a schematic diagram of the load-bearing and positioning component structure of a battery disassembly and flipping platform according to the present invention;

[0035] Figure 3 This is a schematic diagram of the lifting component structure of a battery disassembly and flipping platform according to the present invention;

[0036] Figure 4 This is a schematic diagram of the flipping component structure of a battery disassembly and flipping platform according to the present invention.

[0037] In the picture:

[0038] 1. Base; 11. Bracket; 12. First guide rail; 13. Connecting rod;

[0039] 2. Bearing and positioning assembly; 21. Main beam; 22. Crossbeam; 23. First positioning plate; 24. Slide rail; 25. Positioning bolt; 26. Pressure rod; 27. First lead screw; 28. Turntable; 29. ​​Connecting shaft;

[0040] 3. Lifting assembly; 31. Drive motor; 32. Rotary shaft; 33. Sprocket; 34. Tensioning sprocket; 35. Chain; 36. Carrier plate; 37. Third guide wheel; 38. Counterweight;

[0041] 4. Second positioning plate; 41. Second lead screw; 42. Second lead screw slider;

[0042] 5. Tilting assembly; 51. Carrier frame; 52. First guide wheel; 53. Second guide wheel; 54. Servo motor. Detailed Implementation

[0043] Please see Figure 1-4 This utility model provides a technical solution: a battery disassembly and flipping platform, including a base 1, with brackets 11 fixedly connected to both ends of the base 1, and the tops of the two brackets 11 are fixedly connected by a connecting rod 13.

[0044] A load-bearing positioning component 2 is provided on the upper side of the base 1;

[0045] The bracket 11 has a first guide rail 12 fixed on both sides of its inner cavity. A flipping component 5 is slidably installed between the two first guide rails 12 on the same side. The two ends of the bearing positioning component 2 are rotatably connected to the two flipping components 5 respectively.

[0046] A lifting assembly 3 is installed between the two first guide rails 12, and the connecting end of the lifting assembly 3 is connected to the tilting assembly 5;

[0047] It should be understood that the battery is first placed on the load-bearing positioning component 2, and then positioned using the load-bearing positioning component 2. Then, the lifting component 3 drives the flipping component 5 and the load-bearing positioning component 2 to lift the battery to a certain height, making it convenient for workers to disassemble its surface. At the same time, during the disassembly process, the flipping component 5 can drive the load-bearing positioning component 2 to flip, so that the battery can rotate at different angles, which further improves the convenience of the disassembly operation for workers and reduces the labor intensity of workers.

[0048] like Figure 1 and 2 As shown; the bearing positioning component 2 includes:

[0049] The main beam 21 has connecting shafts 29 fixed at both ends, and the connecting shafts 29 are connected to the corresponding flipping components 5.

[0050] There are two crossbeams 22, which are distributed on both sides of the bottom of the main beam 21. The two side walls of the main beam 21 are fixed with slide rails 24. The outer wall of the slide rail 24 is fitted with a matching first slider. The outer wall of the first slider is fixedly connected to the crossbeam 22 through a connecting plate.

[0051] There are two pressure rods 26, which are located directly above the two crossbeams 22. Each end of the pressure rod 26 is rotatably mounted with a first lead screw slider. The outer wall of the first lead screw slider is fixedly fitted with a turntable 28. The inner cavity of the first lead screw slider is connected to a matching first lead screw 27. The tail end of the first lead screw 27 is rotatably connected to the top end of the crossbeam 22. Rotating the turntable 28 causes the first lead screw slider to descend, thereby causing the pressure rod 26 to descend. Thus, the pressure rod 26 can be used to apply pressure and position the battery from the top.

[0052] There are two first positioning plates 23, which are distributed at both ends of one side wall of the main beam 21. A second slider is fixed to one side wall of the first positioning plate 23. The second slider is slidably mounted on the slide rail 24. The two first positioning plates 23 are used to position the two ends of the battery in the length direction.

[0053] There are four second positioning plates 4, which are distributed at both ends of one side wall of the two crossbeams 22. A second lead screw slider 42 is fixedly connected to one side wall of the second positioning plate 4. The second lead screw slider 42 is fitted onto the outer wall of the matching second lead screw 41. Bearings are fitted at both ends of the second lead screw 41 and the bearings are fixedly connected to one side wall of the crossbeam 22. A handle is fixed to one end of the second lead screw 41. The second positioning plates 4 are used to position the two side walls in the width direction of the battery.

[0054] Positioning bolts 25 are threaded through the outer walls of the first positioning plate 23 and the connecting plate. Fixing strips are fixed on both sides of the main beam 21. Multiple evenly distributed threaded holes are opened on the fixing strips. By engaging the positioning bolts 25 with the threaded holes, the positions of the first positioning plate 23 and the crossbeam 22 can be locked.

[0055] It should be understood that after the battery is hoisted onto the main beam 21, the first positioning plate 23 is first slid to adjust to the optimal position, and the crossbeam 22 is slid to adjust the position of the pressure rod 26. Then, the positioning bolt 25 is engaged with the corresponding threaded hole for positioning. Then, the turntable 28 is rotated to drive the first lead screw slider to rotate, thereby causing the pressure rod 26 to descend and press the pressure rod 26 onto the upper surface of the battery for positioning. Then, the handle is rotated to drive the second lead screw 41 to rotate, thereby driving the second lead screw slider 42 to move, which in turn drives the second positioning plate 4 to move and fit against the side wall in the width direction of the battery, thereby achieving repositioning and ensuring the stability of the battery after positioning. At the same time, it can be compatible with positioning and flipping of batteries of different sizes and shapes.

[0056] like Figure 1 and 4 As shown; the flipping component 5 includes:

[0057] The carrier 51 has first guide wheels 52 rotatably mounted on all four sides of its two side walls, and second guide wheels 53 rotatably mounted on both sides of its top and bottom. The first guide wheels 52 and the second guide wheels 53 are attached to the outer wall and side wall of the first guide rail 12 on both sides of the inner cavity of the bracket 11. The carrier 51 is connected to the corresponding lifting assembly 3.

[0058] The connecting shaft 29 is rotatably connected to the corresponding carrier 51. A servo motor 54 is fixed to the outer wall of one of the carriers 51. The outer end of the drive shaft of the servo motor 54 passes through the carrier 51 and is fixedly connected to one of the connecting shafts 29.

[0059] It should be understood that the servo motor 54 can drive the corresponding connecting shaft 29 to rotate, thereby driving the entire load-bearing positioning component 2 to rotate, thus enabling flipping and adjusting the rotation angle, facilitating disassembly operations by staff.

[0060] like Figure 1 and 2 As shown; the lifting assembly 3 includes:

[0061] The drive motor 31 is mounted on the top of the base 1, and both ends of the drive motor 31 are fixedly connected to the rotating shaft 32.

[0062] There are eight sprockets 33 in total. Four sprockets are distributed at the outer end of each shaft 32. The four sprockets 33 on the same side are arranged in a U-shape. The sprockets 33 are rotatably connected to the inner wall of the wheel frame and the bracket 11. The outer wall of the four sprockets 33 on the same side is wrapped with a chain 35. The two ends of the chain 35 are fixedly connected to the top and bottom of the carrier 51, respectively. The outer end of the shaft 32 is fixedly connected to the corresponding sprocket 33.

[0063] It should be understood that by driving the rotating shaft 32 to rotate through the drive motor 31, one of the sprockets 33 can be driven to rotate. Under the drive of the chain 35, the carrier frame 51 can be raised and lowered, thereby raising and lowering the load-bearing positioning component 2 and the battery, so that the battery is at the optimal height for easy operation.

[0064] Furthermore, a counterweight 38 is fixedly fitted on the outer wall of the chain 35, which makes the chain 35 highly stable during up-and-down movement.

[0065] Furthermore, a tension sprocket 34 is rotatably mounted on the inner wall of the bracket 11, and the lower side of the chain 35 meshes with the tension sprocket 34; the tension sprocket 34 helps to prevent the chain 35 from becoming loose and slipping.

[0066] It is worth mentioning that the counterweight 38 has a carrier plate 36 fixed on both sides of its outer wall. A through hole is opened in the middle of the top of the carrier plate 36. A third guide wheel 37 is rotatably installed on all four sides of one side wall of the carrier plate 36 near the through hole. A second guide rail is fixed in the inner cavity of the bracket 11. The second guide rail passes through the through hole, and the third guide wheel 37 is attached to the outer wall of the second guide rail.

[0067] The stability of the counterweight 38 in lifting and lowering is improved by using the third guide wheel 37 to roll along the outer wall of the second guide rail.

[0068] The specific implementation principle of the battery disassembly and flipping platform in this embodiment is as follows: First, the battery lifting device is placed on the positioning assembly 2, and the first positioning plate 23 is adjusted to the optimal position. At the same time, the sliding beam 22 is used to adjust the position of the pressure rod 26. Then, the positioning bolt 25 is engaged with the corresponding threaded hole for positioning. Then, the turntable 28 is rotated to drive the first lead screw slider to rotate, thereby causing the pressure rod 26 to descend and press the pressure rod 26 onto the upper surface of the battery for positioning. Then, the handle is rotated to drive the second lead screw 41 to rotate, thereby driving the second lead screw slider 42 to move, which can move the second positioning plate. 4. Move the battery to fit against the side wall in the width direction. Drive the rotating shaft 32 to rotate via the drive motor 31, which in turn drives one of the sprockets 33 to rotate. Driven by the chain 35, the carrier frame 51 can be raised and lowered, thereby adjusting the height of the load-bearing positioning component 2 and the battery. Then, the operator can disassemble the battery. During the disassembly process, the servo motor 54 can drive the corresponding connecting shaft 29 to rotate, thereby rotating the entire load-bearing positioning component 2, which can be flipped over and the rotation angle adjusted, making it convenient for the operator to disassemble the battery.

[0069] In addition, the components included in this utility model battery disassembly and flipping platform are all general standard parts or parts known to those skilled in the art. Their structure and principle can be learned by those skilled in the art through technical manuals or conventional experimental methods. In the idle space of this device, all the above-mentioned electrical components, which refer to power components, electrical components, and the matching monitoring computer and power supply, are connected by wires. The specific connection method should refer to the working principle below, and the electrical connection between each electrical component is completed in the order of operation. The detailed connection method is a well-known technology in the field. The following mainly introduces the working principle and process, and will not explain the electrical control.

Claims

1. A battery disassembly and flipping platform, comprising a base (1), characterized in that: Both ends of the base (1) are fixedly connected to brackets (11), and the tops of the two brackets (11) are fixedly connected by a connecting rod (13). A bearing and positioning component (2) is provided on the upper side of the base (1); The bracket (11) has a first guide rail (12) fixed on both sides of its inner cavity. A flipping component (5) is slidably installed between the two first guide rails (12) on the same side. The two ends of the bearing positioning component (2) are rotatably connected to the two flipping components (5) respectively. A lifting assembly (3) is installed between the two first guide rails (12), and the connecting end of the lifting assembly (3) is connected to the flipping assembly (5).

2. The battery disassembly and flipping platform according to claim 1, characterized in that: The bearing positioning component (2) includes: The main beam (21) has connecting shafts (29) fixed at both ends, and the connecting shafts (29) are connected to the corresponding flipping components (5). There are two crossbeams (22) and they are distributed on both sides of the bottom of the main beam (21). The two side walls of the main beam (21) are fixed with slide rails (24). The outer wall of the slide rail (24) is fitted with a matching first slider. The outer wall of the first slider is fixedly connected to the crossbeam (22) through a connecting plate. There are two pressure rods (26), which are distributed directly above the two crossbeams (22). Both ends of the pressure rod (26) are rotatably mounted with a first lead screw slider. The outer wall of the first lead screw slider is fixedly fitted with a turntable (28). The inner cavity of the first lead screw slider is connected to a matching first lead screw (27). The tail end of the first lead screw (27) is rotatably connected to the top end of the crossbeam (22). The first positioning plate (23) consists of two plates, which are distributed at both ends of one side wall of the main beam (21). A second slider is fixed to one side wall of the first positioning plate (23), and the second slider is slidably mounted on the slide rail (24); The second positioning plate (4) has four positions and is distributed at both ends of one side wall of the two crossbeams (22). A second lead screw slider (42) is fixedly connected to one side wall of the second positioning plate (4). The second lead screw slider (42) is fitted onto the outer wall of the matching second lead screw (41). Both ends of the second lead screw (41) are fitted with bearings and the bearings are fixedly connected to one side wall of the crossbeam (22). A handle is fixed to one end of the second lead screw (41). The positioning bolts (25), the outer walls of the first positioning plate (23) and the connecting plate are threaded through the positioning bolts (25), and the two side walls of the main beam (21) are fixed with fixing strips, and the fixing strips are provided with multiple evenly distributed threaded holes.

3. The battery disassembly and flipping platform according to claim 2, characterized in that: The flipping component (5) includes: The carrier (51) has first guide wheels (52) rotatably mounted on all four sides of its two side walls, and second guide wheels (53) rotatably mounted on both the top and bottom sides of the carrier (51). The first guide wheels (52) and the second guide wheels (53) are attached to the outer wall and side wall of the first guide rail (12) on both sides of the inner cavity of the bracket (11). The carrier (51) is connected to the corresponding lifting assembly (3). The connecting shaft (29) and the corresponding carrier (51) are rotatably connected. A servo motor (54) is fixed to the outer wall of one of the carriers (51). The outer end of the drive shaft of the servo motor (54) passes through the carrier (51) and is fixedly connected to one of the connecting shafts (29).

4. The battery disassembly and flipping platform according to claim 3, characterized in that: The lifting assembly (3) includes: A drive motor (31) is installed on the top of the base (1), and both ends of the drive motor (31) are fixedly connected to a rotating shaft (32); There are eight sprockets (33), four of which are distributed at the outer end of each shaft (32). The four sprockets (33) on the same side are arranged in a square shape. The sprockets (33) are rotatably connected to the inner wall of the wheel frame and the bracket (11). The outer wall of the four sprockets (33) on the same side is wrapped with a chain (35). The two ends of the chain (35) are fixedly connected to the top and bottom of the carrier (51) respectively. The outer end of the shaft (32) is fixedly connected to the corresponding sprocket (33).

5. A battery disassembly and flipping platform according to claim 4, characterized in that: A tension sprocket (34) is rotatably mounted on the inner wall of the bracket (11), and the lower side of the chain (35) meshes with the tension sprocket (34).

6. A battery disassembly and flipping platform according to claim 4, characterized in that: The outer wall of the chain (35) is fixedly fitted with a counterweight (38).

7. A battery disassembly and flipping platform according to claim 6, characterized in that: The counterweight (38) has a carrier plate (36) fixed on both sides of its outer wall. A through hole is provided at the top center of the carrier plate (36). A third guide wheel (37) is rotatably installed on all four sides of one side wall of the carrier plate (36) near the through hole. A second guide rail is fixed in the inner cavity of the bracket (11). The second guide rail passes through the through hole. The third guide wheel (37) is attached to the outer wall of the second guide rail.