A follow-up back gas protection device for cylinder welding

Abstract

This utility model relates to the field of welding equipment technology, specifically to a follow-up back-gas protection device for cylinder welding. It includes a hollow cross arm and a chain drive mechanism mounted on the hollow cross arm. The chain drive mechanism includes a chain drive assembly and a drive assembly for driving the chain drive assembly. The chain drive assembly is connected to a moving seat that is slidably connected to the hollow cross arm. The back-gas protection assembly includes a back-gas protection box, a vent plate, and guide members. The vent plate is fixedly mounted inside the back-gas protection box. One end of the back-gas protection box is connected to a gas pipe, the height of which is lower than the height of the vent plate. Multiple guide members are arranged at the bottom of the back-gas protection box, and the guide members are connected to the moving seat. This utility model can penetrate deep into the interior of small-diameter cylinders, releasing inert gas only at the welding area of ​​the cylinder weld, effectively reducing inert gas consumption and effectively protecting the weld area from back-gas, improving the effect of single-sided welding and double-sided forming of the cylinder weld.

Description

Technical Field

[0001] This utility model relates to the field of welding equipment technology, specifically to a follow-up back gas protection device for cylinder welding. Background Technology

[0002] During the manufacturing process of the cylinder, longitudinal and circumferential welding operations are involved, especially for small-diameter cylinders. When the welding process requires single-sided welding and double-sided forming, an inert gas needs to be introduced into the cylinder for back gas protection. Its main function is to protect the welding area, forming a protective layer covering the arc and molten metal area. The inert gas is chemically stable and does not react with the molten metal. It can effectively isolate the surrounding air and prevent the high-temperature molten metal from reacting with oxygen, nitrogen and other gases in the air, thereby avoiding defects such as oxidation and porosity in the weld. In addition, the inert gas can also prevent the nitriding of the molten metal, further ensuring the density and mechanical properties of the weld.

[0003] When preparing small-diameter cylinders, the equipment is difficult to enter the cylinder due to its small diameter. Existing technologies usually use a direct inert gas supply method to introduce inert gas into the small-diameter cylinder. This method consumes a lot of inert gas, resulting in waste. Argon gas, in particular, increases the preparation cost. Furthermore, the single-sided welding of the cylinder welds and double-sided forming effect are not ideal, resulting in low work efficiency. Summary of the Invention

[0004] This invention addresses the problems of high inert gas consumption and unsatisfactory single-sided welding double-sided forming effect in existing technologies that use a direct-through method to introduce inert gas into small-diameter cylinders. It provides a follow-up back-gas protection device for cylinder welding. This device can penetrate deep into the small-diameter cylinder and release inert gas only at the welding area, effectively reducing inert gas consumption and significantly minimizing abnormal usage. Simultaneously, it effectively protects the weld area from back-gas, improving the single-sided welding double-sided forming effect of the cylinder weld.

[0005] To achieve the above objectives, the technical solution of this utility model is: a follow-up back-gas protection device for cylinder welding, comprising a hollow cross arm and a chain drive mechanism disposed on the hollow cross arm. The chain drive mechanism includes a chain drive assembly and a drive assembly for driving the chain drive assembly. The chain drive assembly is connected to a moving seat that is slidably connected to the hollow cross arm. The drive assembly can drive the chain drive assembly to perform transmission, so that the chain drive assembly drives the moving seat to slide on the hollow cross arm, thereby enabling it to enter the interior of a small-diameter cylinder.

[0006] A back-gas protection assembly is installed above the motion seat. This assembly includes a back-gas protection box, a vent plate, and guide members. The vent plate is fixedly installed inside the back-gas protection box and has multiple vent holes evenly distributed on it. One end of the back-gas protection box is connected to an air pipe, the height of which is lower than the height of the vent plate. Multiple guide members are arranged at the bottom of the back-gas protection box and are connected to the motion seat. During the sliding motion of the motion seat on the hollow cross arm, the back-gas protection assembly moves synchronously into the small-diameter cylinder. Inert gas can be introduced into the back-gas protection box through the air pipe, and the inert gas is released through the vent holes on the vent plate. The inert gas is only supplied to the back-gas protection box, and it is also released at the welding area of ​​the cylinder where the back-gas protection box is welded, thus reducing inert gas consumption.

[0007] Furthermore, multiple fixing plates are spaced apart on one side of the hollow cross arm. One end of the hollow cross arm has a slot, and the top has a strip-shaped hole. The top of the hollow cross arm also has a square hole. By installing the fixing plates on the columns outside the cylinder, the hollow cross arm can extend into the cylinder, so that the moving seat can drive the back air protection component into the cylinder.

[0008] Furthermore, the chain drive assembly includes a chain, a driven shaft, a driven sprocket, a tensioner, a drive shaft, and a drive sprocket. Both ends of the driven shaft are respectively engaged in slots. The driven sprocket is rotatably mounted on the driven shaft and located within the strip-shaped hole. Both ends of the drive shaft are provided with seated bearings fixed to the outside of the hollow cross arm. The drive sprocket is fixedly mounted on the drive shaft and located at the square hole. The chain is mounted on the drive sprocket and the driven sprocket. When the drive sprocket rotates, the driven sprocket can be driven to rotate through the chain. The chain is used to drive the moving seat to slide on the hollow cross arm.

[0009] Furthermore, both ends of the driven shaft are connected to the tensioning element. The tensioning element includes a tensioning seat, a tensioning screw, and a tensioning nut. The tensioning seat is fixedly disposed on the outside of the hollow cross arm. The tensioning screw is threadedly connected to the tensioning seat and one end passes through the driven shaft. The tensioning screw is slidably connected to the driven shaft. Both sides of the driven shaft are provided with tensioning nuts that are threadedly connected to the tensioning screw. By changing the position of the two tensioning nuts, the position of the driven shaft can be adjusted, thereby adjusting the position of the driven sprocket and thus adjusting the chain tension.

[0010] Furthermore, the drive assembly includes a drive support, a motor, a reducer, and an electromagnetic clutch. The drive support is fixedly mounted on the outside of the hollow cross arm, the reducer is mounted on the outside of the drive support, the output shaft of the motor is connected to the input shaft of the reducer, and the output shaft of the reducer is connected to the drive shaft via the electromagnetic clutch.

[0011] Furthermore, a connecting block is fixedly installed at the bottom of the horizontal part of the motion seat, and the connecting block is fixedly sleeved on the chain; a U-shaped block with an upward opening is provided on the inner side of the vertical part of the motion seat, and a slider is fixedly installed on the inner side of the U-shaped block. The motion seat is connected to the chain through the connecting block, so that the chain drives the motion seat to slide on the hollow cross arm during transmission.

[0012] Furthermore, L-shaped plates are fixedly installed on both sides of the hollow cross arm, and linear guide rails fixed to the outside of the hollow cross arm are installed inside the L-shaped plates. Stops are provided at both ends of the linear guide rails. A U-shaped block is inserted into the vertical part of the L-shaped plate and slidably connected to it. The slider is slidably mounted on the linear guide rail. Through the cooperation between the U-shaped block and the vertical part of the L-shaped plate, and between the slider and the linear guide rail, the motion seat can easily slide on the hollow cross arm, while also guiding the movement of the motion seat.

[0013] Furthermore, the guide component includes a guide slide shaft, a spring, and a limiting plate. The upper end of the guide slide shaft is connected to the back vent protection box, and the lower end passes through the motion seat and is connected to the limiting plate. The guide slide shaft is slidably connected to the motion seat. The spring is sleeved on the guide slide shaft and located between the back vent protection box and the motion seat. The elastic force of the spring supports the back vent protection box above the motion seat, and the limiting plate can prevent the guide slide shaft from detaching from the motion seat under the action of the spring.

[0014] The beneficial effects of this utility model through the above technical solution are as follows:

[0015] This utility model has a reasonable structure and good performance. It can penetrate deep into the interior of a small-diameter cylinder and release inert gas only at the welding area of ​​the cylinder. This can effectively reduce the consumption of inert gas, thereby reducing the cost of manufacturing the cylinder. It can also significantly reduce the abnormal use of inert gas, effectively protect the weld area from back gas, improve the effect of single-sided welding and double-sided forming of the cylinder weld, and improve work efficiency.

[0016] This invention extends a hollow crossbeam into a small-diameter cylinder and uses a drive assembly to drive a chain transmission assembly. The chain transmission assembly drives a moving seat to slide on the hollow crossbeam into the small-diameter cylinder. The moving seat drives a back-gas protection assembly to the welding area of ​​the cylinder to release inert gas. This protects only the welding area of ​​the cylinder from air, providing good protection. It eliminates the need to directly supply inert gas into the small-diameter cylinder, reducing abnormal consumption of inert gas and improving the effect of single-sided welding and double-sided forming of the cylinder weld.

[0017] This utility model's back-gas protection component introduces inert gas into the back-gas protection box through a gas pipe. The inert gas is then released through a vent plate inside the back-gas protection box. By using a method where the inert gas is only introduced into the back-gas protection box, the consumption of inert gas is reduced. In addition, the released inert gas only protects the welding area of ​​the cylinder, resulting in good weld formation of the cylinder. Attached Figure Description

[0018] Figure 1 This is a schematic diagram of the structure of a follow-up back gas protection device for cylinder welding according to this utility model. Figure 1 ;

[0019] Figure 2 This is a schematic diagram of the structure of a follow-up back gas protection device for cylinder welding according to this utility model. Figure 2 ;

[0020] Figure 3 yes Figure 2 Enlarged structural diagram at point A;

[0021] Figure 4 yes Figure 2 Enlarged structural diagram at point B;

[0022] Figure 5 This is a schematic diagram of the structure of a follow-up back gas protection device for cylinder welding according to this utility model. Figure 3 ;

[0023] Figure 6 This is a schematic diagram of the structure of a follow-up back gas protection device for cylinder welding according to this utility model. Figure 4 ;

[0024] Figure 7 yes Figure 6 Enlarged structural diagram at point C;

[0025] Figure 8 This is a schematic diagram of the back air protection box and motion seat of this utility model. Figure 1 ;

[0026] Figure 9 This is a schematic diagram of the back air protection box and motion seat of this utility model. Figure 2 .

[0027] The attached diagram is labeled as follows: 1 is a hollow crossarm, 101 is a fixed plate, 102 is a slot, 2 is a drive assembly, 201 is a drive support, 202 is a motor, 203 is a reducer, 204 is an electromagnetic clutch, 3 is a chain drive assembly, 301 is a chain, 302 is a driven shaft, 303 is a driven sprocket, 304 is a tensioning element, 3041 is a tensioning seat, 3042 is a tensioning screw, 3043 is a tensioning nut, 305 is a drive shaft, 306 is a drive sprocket, 307 is a bearing with a seat, 4 is an L-shaped plate, 5 is a linear guide rail, 501 is a stop block, 6 is a motion seat, 601 is a connecting block, 602 is a U-shaped block, 603 is a slider, 7 is a back air protection box, 8 is a vent plate, 9 is an air pipe, 10 is a guide shaft, 11 is a spring, and 12 is a limiting plate. Detailed Implementation

[0028] The present invention will be further described below with reference to the accompanying drawings and specific embodiments:

[0029] like Figures 1-9 As shown, a follow-up back gas protection device for cylinder welding includes a hollow cross arm 1 and a chain drive mechanism disposed on the hollow cross arm 1. The hollow cross arm 1 is a square columnar structure with a hollow interior. The chain drive mechanism includes a chain drive assembly 3 and a drive assembly 2 that drives the chain drive assembly 3 to move. The chain drive assembly 3 is connected to a motion seat 6 that is slidably connected to the hollow cross arm 1. In this embodiment, the drive assembly 2 drives the chain drive assembly 3 to run, and the chain drive assembly 3 drives the motion seat 6 to slide on the hollow cross arm 1. In specific use, the hollow cross arm 1 extends into the interior of a small-diameter cylinder, and the motion seat 6 can run into the interior of the small-diameter cylinder under the action of the chain drive assembly 3.

[0030] A back-gas protection assembly is provided above the motion seat 6. The back-gas protection assembly includes a back-gas protection box 7, a vent plate 8, and guide members. The vent plate 8 is fixedly installed inside the back-gas protection box 7 and is used to seal the back-gas protection box 7. Multiple vent holes are evenly distributed on the vent plate 8. One end of the back-gas protection box 7 is connected to an air pipe 9. The height of the air pipe 9 is lower than the height of the vent plate 8, so that the air pipe 9 can enter the interior of the back-gas protection box 7 and allow the inert gas to be released through the vent plate 8. Multiple guide members are provided at the bottom of the back-gas protection box 7 and are connected to the motion seat 6. In this embodiment, there are four guide members at the bottom of the back gas protection box 7, which are fixed at the bottom corners of the back gas protection box 7. The guide members enable the motion seat 6 to drive the back gas protection box 7 to move synchronously. The motion seat 6 drives the back gas protection box 7 to penetrate into the welding area of ​​the cylinder inside the small diameter cylinder. Only the back gas protection box 7 passes inert gas to the welding area to provide back gas protection for the welding area, thereby reducing the consumption of inert gas and improving the effect of single-sided welding and double-sided forming of the cylinder weld.

[0031] Multiple fixing plates 101 are spaced apart on one side of the hollow cross arm 1. One end of the hollow cross arm 1 has a slot 102, and the top has a strip-shaped hole. A square hole is also provided at the top of the hollow cross arm 1. In this embodiment, three fixing plates 101 are bolted to one side of the hollow cross arm 1. During the cylinder preparation and welding operation, a column can be fixed at the work site. By fixing the fixing plates 101 to the column, the hollow cross arm 1 can be easily inserted into the small-diameter cylinder.

[0032] The chain drive assembly 3 includes a chain 301, a driven shaft 302, a driven sprocket 303, a tensioner 304, a drive shaft 305, and a drive sprocket 306. The driven shaft 302 has both ends respectively fitted into slots 102. The driven sprocket 303 is rotatably sleeved on the driven shaft 302 and located within the slotted hole. The slot 102 facilitates the installation of the driven shaft 302 into the hollow crossarm 1, and also facilitates the adjustment of the driven shaft 302's position via the tensioner 304, thereby adjusting the tension of the chain 301. Additionally, the slotted hole... The hole provides an installation position for the driven sprocket 303, so as to install the driven sprocket 303 into the interior of the hollow cross arm 1; both ends of the drive shaft 305 are provided with seated bearings 307 fixed to the outside of the hollow cross arm 1. The seated bearings 307 are bolted to the outside of the hollow cross arm 1, so that the drive shaft 305 can drive the drive sprocket 306 to rotate. The drive sprocket 306 is fixedly sleeved on the drive shaft 305 and located at the square hole; the chain 301 is sleeved on the drive sprocket 306 and the driven sprocket 303. The hollow cross arm 1 has mounting slots on both sides corresponding to the square holes. The two ends of the drive shaft 305 are respectively mounted in the mounting slots on both sides of the hollow cross arm 1. The mounting slots provide the mounting position for the drive shaft 305, and the square holes provide the mounting position for the drive sprocket 306. The square holes and the strip holes facilitate the lower layer of the chain 301 to be located inside the hollow cross arm 1, so that the chain 301 can drive the motion seat 6 to slide on the hollow cross arm 1.

[0033] Both ends of the driven shaft 302 are connected to the tensioning member 304. The tensioning member 304 includes a tensioning seat 3041, a tensioning screw 3042, and a tensioning nut 3043. The tensioning seat 3041 is fixedly disposed on the outside of the hollow cross arm 1. The tensioning screw 3042 is threadedly connected to the tensioning seat 3041 and one end passes through the driven shaft 302. The tensioning screw 3042 is slidably connected to the driven shaft 302. The tensioning nuts 3043 threadedly connected to the tensioning screw 3042 are provided on both sides of the driven shaft 302. In this embodiment, the driven shaft 302 has a through hole at its end for the tensioning screw 3042 to pass through. The tensioning nut 3043 restricts the position of the driven shaft 302. By adjusting the position of the two tensioning nuts 3043 on the tensioning screw 3042, the position of the driven shaft 302 on the tensioning screw 3042 and within the slot 102 can be adjusted, thereby adjusting the position of the driven sprocket 303 and thus achieving the effect of adjusting the tension of the chain 301.

[0034] The drive assembly 2 includes a drive support 201, a motor 202, a reducer 203, and an electromagnetic clutch 204. The drive support 201 is fixedly mounted on the outside of the hollow cross arm 1. The reducer 203 is mounted on the outside of the drive support 201. The output shaft of the motor 202 is connected to the input shaft of the reducer 203. The output shaft of the reducer 203 is connected to the drive shaft 305 via the electromagnetic clutch 204. In this embodiment, when the electromagnetic clutch 204 is engaged, the motor 202 and the reducer 203 drive the drive shaft 305 to rotate via the electromagnetic clutch 204. When the electromagnetic clutch 204 is released, the initial position of the back air protection assembly can be manually adjusted.

[0035] Two connecting blocks 601 are fixedly installed at the bottom of the horizontal part of the motion seat 6. The connecting blocks 601 are in the form of a "U" shape and their vertical parts are fixedly connected to the motion seat 6. The connecting blocks 601 are fixedly sleeved on the chain 301. The connecting blocks 601 can be connected to the chain 301 by the cooperation of bolts and nuts. The inner side of the vertical part of the motion seat 6 is provided with an upward-facing U-shaped block 602. A slider 603 is fixedly installed on the inner side of the U-shaped block 602.

[0036] Both sides of the hollow cross arm 1 are fixedly provided with L-shaped plates 4. The horizontal part of the L-shaped plates 4 is fixedly connected to the hollow cross arm 1. A linear guide rail 5 fixed to the outside of the hollow cross arm 1 is provided inside the L-shaped plates 4. Both ends of the linear guide rail 5 are provided with stops 501. A U-shaped block 602 is inserted into the vertical part of the L-shaped plate 4 and is slidably connected to the vertical part of the L-shaped plate 4. A slider 603 is slidably disposed on the linear guide rail 5. In this embodiment, the cooperation between the U-shaped block 602 and the vertical part of the L-shaped plate 4 and the slider 603 and the linear guide rail 5 facilitates the sliding of the motion seat 6 on the hollow cross arm 1 and guides the movement of the motion seat 6. In addition, the stops 501 block the slider 603.

[0037] The guide component includes a guide slide shaft 10, a spring 11, and a limiting plate 12. The upper end of the guide slide shaft 10 is connected to the back vent protection box 7, and the lower end passes through the motion seat 6 and is connected to the limiting plate 12. The guide slide shaft 10 and the motion seat 6 are slidably connected. The spring 11 is sleeved on the guide slide shaft 10 and is located between the back vent protection box 7 and the motion seat 6. In this embodiment, a sliding hole matching the guide slide shaft 10 is opened at the horizontal corner of the motion seat 6. The guide slide shaft 10 is slidably connected to the motion seat 6 through the sliding hole. The diameter of the limiting plate 12 is larger than the diameter of the sliding hole. The limiting plate 12 is fixed to the bottom of the guide slide shaft 10 by bolts. The limiting plate 12 plays a limiting role for the guide slide shaft 10 to prevent the guide slide shaft 10 from detaching from the motion seat 6. The back vent protection box 7 is supported above the motion seat 6 by the elastic force of the spring 11.

[0038] The working principle of this utility model is as follows: When longitudinal and circumferential seam welding operations are performed on the preparation of small-diameter cylinders, the electromagnetic clutch 204 is released to adjust the initial position of the back gas protection box 7, and the fixing plate 101 is fixed on the column in the welding operation area so that the hollow cross arm 1 is in a suspended state and the hollow cross arm 1 extends into the interior of the small-diameter cylinder.

[0039] When the welding area of ​​the cylinder is protected with inert gas, the electromagnetic clutch 204 is engaged, and the output shaft of the motor 202 drives the input shaft of the reducer 203 to rotate. The output shaft of the reducer 203 drives the drive shaft 305 to rotate through the electromagnetic clutch 204. The drive shaft 305 drives the drive sprocket 303 to rotate. The drive sprocket 303 drives the driven sprocket 303 to rotate on the driven shaft 302 through the chain 301. The chain 301 drives the moving seat 6 to run on the hollow cross arm 1 into the small-diameter cylinder through the connecting block 601. The component drives the back gas protection box 7 to move into the small-diameter cylinder. When the back gas protection box 7 reaches the welding area of ​​the cylinder, the motor 202 is turned off. Then, inert gas is introduced into the back gas protection box 7 through the gas pipe 9. The inert gas is released from the vent hole on the vent plate 8 inside the back gas protection box 7. The inert gas only protects the welding area of ​​the cylinder and isolates it from the air. Finally, the welding area can be welded on the outside of the small-diameter cylinder by the welding torch. This reduces the abnormal use of inert gas and improves the effect of single-sided welding and double-sided forming of the cylinder weld.

[0040] The embodiments described above are merely preferred embodiments of the utility model and are not intended to limit the scope of the utility model. Therefore, all equivalent changes or modifications made to the technical solutions described in the scope of the utility model patent application should be included within the scope of the utility model patent application.

Claims

1. A trailing back gas shield for shell welding, characterized by, The device includes a hollow cross arm (1) and a chain drive mechanism mounted on the hollow cross arm (1). The chain drive mechanism includes a chain drive assembly (3) and a drive assembly (2) that drives the chain drive assembly (3) to move. The chain drive assembly (3) is connected to a motion seat (6) that is slidably connected to the hollow cross arm (1). A back air protection assembly is provided above the motion seat (6). The back air protection assembly includes a back air protection box (7), a vent plate (8), and guide members. The vent plate (8) is fixedly mounted inside the back air protection box (7). Multiple vent holes are evenly distributed on the vent plate (8). One end of the back air protection box (7) is connected to an air pipe (9). The height of the air pipe (9) is lower than the height of the vent plate (8). Multiple guide members are provided at the bottom of the back air protection box (7). The guide members are connected to the motion seat (6).

2. A trailing back gas shield for cylinder welding as defined in claim 1, wherein The hollow cross arm (1) has multiple fixing plates (101) spaced apart on one side. The hollow cross arm (1) has a slot (102) at one end and a strip hole at the top. The hollow cross arm (1) also has a square hole at the top.

3. The follow-up back gas protection device for cylinder welding according to claim 2, characterized in that, The chain drive assembly (3) includes a chain (301), a driven shaft (302), a driven sprocket (303), a tensioner (304), a drive shaft (305), and a drive sprocket (306). The driven shaft (302) is respectively fitted into the slot (102) at both ends. The driven sprocket (303) is rotatably sleeved on the driven shaft (302) and located in the strip hole. The drive shaft (305) is provided with seated bearings (307) fixed on the outside of the hollow cross arm (1) at both ends. The drive sprocket (306) is fixedly sleeved on the drive shaft (305) and located at the square hole. The chain (301) is sleeved on the drive sprocket (306) and the driven sprocket (303).

4. A follow-up back gas protection device for cylinder welding according to claim 3, characterized in that, Both ends of the driven shaft (302) are connected to the tensioning member (304). The tensioning member (304) includes a tensioning seat (3041), a tensioning screw (3042), and a tensioning nut (3043). The tensioning seat (3041) is fixedly disposed on the outside of the hollow cross arm (1). The tensioning screw (3042) is threadedly connected to the tensioning seat (3041) and one end passes through the driven shaft (302). The tensioning screw (3042) is slidably connected to the driven shaft (302). Both sides of the driven shaft (302) are provided with tensioning nuts (3043) that are threadedly connected to the tensioning screw (3042).

5. A follow-up back gas protection device for cylinder welding according to claim 3, characterized in that, The drive assembly (2) includes a drive support (201), a motor (202), a reducer (203), and an electromagnetic clutch (204). The drive support (201) is fixedly installed on the outside of the hollow cross arm (1). The reducer (203) is installed on the outside of the drive support (201). The output shaft of the motor (202) is connected to the input shaft of the reducer (203). The output shaft of the reducer (203) is connected to the drive shaft (305) via the electromagnetic clutch (204).

6. A follow-up backflow protection device for cylinder welding according to claim 5, characterized in that, A connecting block (601) is fixedly installed at the bottom of the horizontal part of the motion seat (6), and the connecting block (601) is fixedly sleeved on the chain (301); a U-shaped block (602) with an upward opening is provided on the inner side of the vertical part of the motion seat (6), and a slider (603) is fixedly installed on the inner side of the U-shaped block (602).

7. A follow-up back gas protection device for cylinder welding according to claim 6, characterized in that, Both sides of the hollow cross arm (1) are fixedly provided with L-shaped plates (4), and a linear guide rail (5) fixed to the outside of the hollow cross arm (1) is provided inside the L-shaped plate (4). Both ends of the linear guide rail (5) are provided with stop blocks (501); the U-shaped block (602) is inserted into the vertical part of the L-shaped plate (4) and is slidably connected to the vertical part of the L-shaped plate (4); the slider (603) is slidably disposed on the linear guide rail (5).

8. A follow-up back gas protection device for cylinder welding according to claim 1, characterized in that, The guide component includes a guide slide shaft (10), a spring (11), and a limiting plate (12). The upper end of the guide slide shaft (10) is connected to the back air protection box (7), and the lower end passes through the motion seat (6) and is connected to the limiting plate (12). The guide slide shaft (10) and the motion seat (6) are slidably connected. The spring (11) is sleeved on the guide slide shaft (10) and is located between the back air protection box (7) and the motion seat (6).

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