An automatic conveying device for aquatic product processing and production
By designing automated transport equipment, and utilizing a limit plate driven by an airbag and hydraulic rod in conjunction with a scraping plate, the problems of efficiency and damage in rotary fish scalers were solved, achieving thorough removal of fish scales and protection of the fish body.
Patent Information
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- GUANGDONG XIANGLIANG FOOD TECH CO LTD
- Filing Date
- 2026-04-13
- Publication Date
- 2026-06-30
Smart Images

Figure CN122300879A_ABST
Abstract
Description
Technical Field
[0001] This invention relates to the field of aquatic product transportation technology, and more specifically, to an automated transportation device for aquatic product processing and production. Background Technology
[0002] Freshwater fish, with their tender flesh and rich nutrients, are a core raw material in aquatic product processing. Scale removal is a crucial step in the pre-processing of freshwater fish, directly affecting the efficiency and quality of subsequent processing steps such as cutting, marinating, and packaging. As the freshwater fish processing industry moves towards large-scale and automated production, traditional manual scale removal, due to its low efficiency, high labor intensity, and difficulty in controlling hygiene standards, can no longer meet the demands of industrial production. Rotary drum scalers, with their simple structure, convenient operation, and efficient double-sided simultaneous scale removal, have become the mainstream equipment for automated scale removal in early freshwater fish processing and are widely used in various freshwater fish processing and transportation lines.
[0003] While rotary fish scalers improve processing efficiency, the random tumbling and friction-based scaling of the fish within the rotating drum, without precise positioning and contact control, creates blind spots in scale removal. Furthermore, achieving simultaneous scaling on both sides requires increasing the drum's rotation speed to enhance collision and friction between fish, making this "extensive" processing method inevitably damage the fish and negatively impacting subsequent fish meat processing.
[0004] To overcome the inherent defects of the rotary fish scaler, there is an urgent need for an automated transport device for aquatic product processing that balances processing efficiency, thorough scale removal, and minimal damage to the fish. Summary of the Invention
[0005] This invention provides an automated transportation device for aquatic product processing, which solves the problems of existing fish descaling equipment being unable to balance processing efficiency, thorough descaling, and low damage to the fish.
[0006] To achieve the above objectives, the automated transport equipment for aquatic product processing includes a pair of spaced-apart mounting plates, with multiple long conveyor rollers and multiple pairs of short conveyor rollers rotatably connected between the two mounting plates. Each pair of short conveyor rollers includes two rollers, and a cantilever frame is fixedly connected above the two mounting plates. An adjustable height limiting plate is provided between the lifting frame and the long conveyor rollers. A drive roller for scraping fish scales is rotatably connected below the limiting plate. A pressure block is provided on one side of the limiting plate. The pressure block is slidably connected to the lifting frame. An air-filled airbag is provided on the side of the pressure block away from the limiting plate. An operation box is provided between multiple pairs of long conveyor rollers. The operation box has a transfer chamber that communicates with the airbag. A lifting plate is slidably connected to the top of the operation box. The bottom of the lifting plate is kept in balance with the air pressure inside the transfer chamber. When the fish's tail passes the top of the lifting plate, the limiting plate slides down and squeezes the air bladder to compress the gas inside into the transfer chamber, so that the lifting plate causes the fish's tail to lift up and approach the drive roller.
[0007] In the above technical solution, the limiting plate compresses the airbag, and the gas inside the airbag is squeezed into the transfer chamber. The lifting plate is raised due to the increased air pressure at the bottom. The lifting plate lifts the fish tail towards the drive roller, thereby scraping off the scales on the fish tail.
[0008] Based on this, the top height of the operating box is lower than the top height of the short conveyor shaft, one end of the short conveyor shaft is rotatably connected to the mounting plate, and the other end of the short conveyor shaft is rotatably connected to the side wall of the operating box.
[0009] With this design, when the rotating short conveyor roller drives the fish to move, the top of the control box is slightly lower than the top of the short conveyor roller, thus preventing the control box from obstructing the fish's forward movement.
[0010] In another technical solution, rotating bolts are fixedly connected to the bottom of both ends of the limiting plate, and the drive roller is rotatably connected between the two rotating bolts. Multiple scraping plates are fixedly connected to the periphery of the drive roller.
[0011] Based on the above, a hydraulic rod and several guide rods are provided above the limiting plate. The hydraulic rod includes a cylinder and a piston end. The cylinder is fixedly connected to the lifting frame, the piston end is fixedly connected to the top of the limiting plate, one end of the guide rod is fixedly connected to the top of the limiting plate, and the guide rod is slidably connected to the lifting frame. The lifting plate is adjacent to the drive roller.
[0012] Furthermore, the scraper is curved. When the scraper rotates to directly below the drive roller, the concave side of the scraper points to the upstream side of the fish's movement. The radius of the drive roller gradually decreases from both ends to the middle to adapt to the shape of the fish.
[0013] In this technical solution, during the movement of the fish body driven by the short conveyor roller, the fish tail is placed forward along the direction of the fish body movement. When the fish tail reaches the bottom of the drive roller, the piston end of the hydraulic rod drives the limiting plate to descend. The descending limiting plate drives the drive roller to move closer to the tail of the fish body, thereby adapting to the thinner part of the fish tail. The motor drives the drive roller to rotate, and the scale scraping plate on its surface scrapes off the fish scales on the surface of the fish body.
[0014] In addition, the limiting plate has a driving slope on the side near the pressure block, and the pressure block has a pressure-bearing slope on the side near the limiting plate, with the driving slope and the pressure-bearing slope fitting together.
[0015] Furthermore, a slider is fixedly connected to the top of the pressure block, and a groove is provided on the top of the cantilever frame. The slider is slidably connected in the groove, and a spring is provided between one side of the slider and the side wall of the groove. The spring is used to drive the slider to slide in the groove and then return to its original position.
[0016] The pressure block has an extrusion plate on the side away from the limiting plate, the airbag is located inside the extrusion plate, the extrusion plate is slidably connected to the side wall of the cantilever frame, and the extrusion plate is fixedly connected to the pressure block.
[0017] As can be seen from the above scheme, when the hydraulic rod drives the limiting plate to slide down, the pressure-bearing inclined surface that is in contact with the driving inclined surface is driven by the descending driving inclined surface to slide away from the limiting plate. The pressure block pushes the extrusion plate to slide towards the side wall of the cantilever frame, thereby compressing the airbag by reducing the space enclosed by the extrusion plate and the side wall of the cantilever frame.
[0018] Based on the above description, the beneficial effects of the present invention compared with the prior art are as follows: When the fish tail reaches below the drive roller, the piston end of the hydraulic rod drives the limiting plate to descend. The descending limiting plate drives the drive roller to move closer to the tail of the fish body, thus fitting the thinner part of the fish tail. The pressure block pushes the extrusion plate to slide closer to the side wall of the cantilever frame. By reducing the space enclosed by the extrusion plate and the side wall of the cantilever frame, the airbag is compressed. The gas inside the airbag passes through the first and second air pipes and enters the transfer chamber, increasing the air pressure inside the transfer chamber. The pressure support is then affected by the expansion force of the gas at the bottom of the anti-detachment plate and rises. Multiple rising pressure supports drive the lifting plate to rise, thereby lifting the fish tail part that is transported to the top of the lifting plate, so that the thin scales on the fish tail can also be scraped off by the scale scraper. Attached Figure Description
[0019] The accompanying drawings are provided to further illustrate the invention and form part of the specification. They are used in conjunction with embodiments of the invention to explain the invention and do not constitute a limitation thereof. In the drawings: Figure 1 This is a perspective view of the overall structure of the present invention; Figure 2 This is a partial sectional side view of the present invention; Figure 3 This is a diagram showing the positional relationship between the conveying roller and the control box of the present invention; Figure 4 This is a perspective view showing the positional distribution of the scraper blades on the drive roller according to the present invention; Figure 5 This is a side view showing the positional distribution of the scraper blades on the drive roller according to the present invention; Figure 6 This is a side view schematic diagram of the driving roller descending to scrape off fish tail scales according to the present invention. Figure 7 This is a side view schematic diagram illustrating the principle of the limiting bolt descending to drive the pressure block to translate according to the present invention; Figure 8 This is a diagram showing the internal gas flow direction of the airbag of the present invention when it is compressed; Figure 9 This is a side view schematic diagram illustrating the principle of the pressure support rising during air intake in the transfer chamber of the present invention. Figure 10 This is a side view of the principle of the lifting plate being raised by the lifting support of the present invention.
[0020] The meanings of the labels in the diagram are as follows: 100. Mounting plate; 101. Long conveyor roller; 102. First air pipe; 103. Second air pipe; 104. Inlet; 110. Elevating frame; 120. Control box; 200. Drive roller; 201. Scraper; 210. Limiting plate; 211. Drive inclined plane; 212. Hydraulic rod; 213. Guide rod; 220. Pressure block; 221. Pressure inclined plane; 230. Slider; 231. Slide groove; 232. Spring; 300. Airbag; 310. Extrusion plate; 400. Transfer chamber; 401. Limiting chamber; 402. Pressure bearing support; 403. Limiting ring; 404. Anti-detachment plate; 410. Lifting plate. Detailed Implementation
[0021] The technical solutions in 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.
[0022] In existing technologies, descaling is performed using a rotary drum descaling machine. While this improves processing efficiency, the fish are randomly rolled around inside the drum after being placed in, resulting in frictional descaling without precise positioning and contact control. This leads to blind spots in scale removal. Furthermore, to achieve simultaneous descaling on both sides, the drum needs to rotate at a certain speed to increase collision and friction between the fish. This "extensive" processing method inevitably causes multiple types of damage to the fish, making it difficult to balance efficient seafood processing and transportation, thorough descaling, and minimal damage to the fish.
[0023] Please see Figure 1 and Figure 2In order to solve the problems existing in the prior art, the purpose of the present invention is to provide an automated transportation equipment for aquatic product processing and production. The transportation equipment includes a pair of spaced-apart mounting plates 100, and a plurality of long conveying rollers 101 and a plurality of pairs of short conveying rollers are rotatably connected between the two mounting plates 100. Each pair of short conveying rollers includes two rollers. A lifting frame 110 is fixedly connected above the two mounting plates 100. An adjustable height limiting plate 210 is provided between the lifting frame 110 and the long conveying roller 101. A drive roller 200 for scraping fish scales is rotatably connected below the limiting plate 210. A pressure block 220 is provided on one side of the limiting plate 210. The pressure block 220 is slidably connected to the lifting frame 110. An air-filled airbag 300 is provided on the side of the pressure block 220 away from the limiting plate 210. An operation box 120 is provided between multiple pairs of long conveying rollers 101. A transfer chamber 400 communicating with the airbag 300 is provided inside the operation box 120. A lifting plate 410 is slidably connected to the top of the operation box 120. The bottom of the lifting plate 410 is kept in balance with the air pressure inside the transfer chamber 400. When the fish's tail passes the top of the lifting plate 410, the limiting plate 210 slides down and squeezes the airbag 300 to compress the gas inside into the transfer chamber 400, so that the lifting plate 410 drives the fish tail to lift up and approach the drive roller 200.
[0024] During implementation, fish products are placed on top of the short conveyor roller at the inlet 104. The rotating short conveyor roller drives the fish body to move towards the long conveyor roller 101. Since the thickness of the fish body's tail is lower than that of its back and head, when the short conveyor roller drives the fish product to the top of the lifting plate 410, the limiting plate 210 drives the driving roller 200 to move downward, so that the driving roller 200 moves closer to the fish body. At the same time, the limiting plate 210 compresses the air bladder 300, and the gas inside the air bladder 300 is squeezed into the transfer chamber 400. The lifting plate 410 is raised due to the increased air pressure at the bottom. The lifting plate 410 lifts the fish tail closer to the driving roller 200, thereby scraping off the scales on the fish tail.
[0025] For a better understanding of the above content, please refer to [link / reference]. Figure 3 The top height of the control box 120 is lower than the top height of the short conveyor shaft. One end of the short conveyor shaft is rotatably connected to the mounting plate 100, and the other end of the short conveyor shaft is rotatably connected to the side wall of the control box 120.
[0026] It should be noted that the short conveyor shaft and the long conveyor roller 101 can be driven by a motor to rotate independently, or they can be connected coaxially with a pulley and then connected together by a belt to make multiple short conveyor shafts and long conveyor rollers 101 rotate synchronously. The specific choice depends on the actual production needs.
[0027] When the rotating short conveyor roller drives the fish to move, the top of the control box 120 is slightly lower than the top of the short conveyor roller, thereby preventing the control box 120 from obstructing the fish's forward movement.
[0028] Next, as Figure 4 and Figure 5 As shown, rotating bolts are fixedly connected to the bottom of both ends of the limiting plate 210, which are far apart. The drive roller 200 is rotatably connected between the two rotating bolts. Multiple scraping plates 201 are fixedly connected to the periphery of the drive roller 200.
[0029] Based on the above, a hydraulic rod 212 and several guide rods 213 are provided above the limiting plate 210. The hydraulic rod 212 includes a cylinder and a piston end. The cylinder is fixedly connected to the lifting frame 110, and the piston end is fixedly connected to the top of the limiting plate 210. One end of the guide rod 213 is fixedly connected to the top of the limiting plate 210, and the guide rod 213 is slidably connected to the lifting frame 110. The lifting plate 410 is adjacent to the drive roller 200.
[0030] Furthermore, the scale scraper 201 is curved. When the scale scraper 201 rotates to be directly below the drive roller 200, the concave side of the scale scraper 201 points to the upstream side of the fish body movement. The radius of the drive roller 200 gradually decreases from both ends to the middle to adapt to the shape of the fish body.
[0031] In other words, the mucus on the fish's surface has been removed before scaling, and the surfaces of the short and long conveyor rollers 101 are coated with a high-friction coefficient coating to ensure that the short and long conveyor rollers 101 provide sufficient driving force to the fish during scaling, ensuring that the fish can always move forward. During the movement of the fish driven by the short conveyor roller, the tail faces forward along the direction of the fish's movement. When the tail reaches below the drive roller 200, the piston end of the hydraulic rod 212 drives the limiting plate 210 to descend. The descending limiting plate 210 drives the drive roller 200 to move closer to the tail of the fish, thereby adapting to the thinner tail portion. The motor drives the drive roller 200 to rotate, and the scaling plate 201 on its outer surface scrapes off the fish scales from the fish's surface.
[0032] exist Figure 6 and Figure 7 In the middle, the limiting plate 210 has a driving slope 211 on the side near the pressure block 220, and the pressure block 220 has a pressure-bearing slope 221 on the side near the limiting plate 210. The driving slope 211 and the pressure-bearing slope 221 are in contact with each other.
[0033] Furthermore, a slider 230 is fixedly connected to the top of the pressure block 220, and a groove 231 is provided on the top of the cantilever frame 110. The slider 230 is slidably connected in the groove 231. A spring 232 is provided between one side of the slider 230 and the side wall of the groove 231. The spring 232 is used to drive the slider 230 to slide in the groove 231 and then return to its original position.
[0034] A compression plate 310 is provided on the side of the pressure block 220 away from the limiting plate 210. The airbag 300 is located inside the compression plate 310. The compression plate 310 is slidably connected to the side wall of the cantilever frame 110. The compression plate 310 is fixedly connected to the pressure block 220.
[0035] It should be disclosed that when the hydraulic rod 212 drives the limiting plate 210 to slide down, the pressure-bearing inclined surface 221, which is in contact with the driving inclined surface 211, is driven by the descending driving inclined surface 211 to slide away from the limiting plate 210. The pressure block 220 pushes the extrusion plate 310 to slide closer to the side wall of the cantilever frame 110, thereby compressing the airbag 300 by reducing the space enclosed by the extrusion plate 310 and the side wall of the cantilever frame 110.
[0036] Based on the above explanation, the following will further combine... Figures 8-10 Explain the superior effect of lifting the lifting plate 410: One side of the airbag 300 is connected to a first air tube 102, and one side of the transfer chamber 400 is connected to a second air tube 103. The first air tube 102 and the second air tube 103 are connected through a sealed hose. The top of the transfer chamber 400 is connected to several limiting chambers 401. Each limiting chamber 401 is slidably connected to a pressure support 402. The ends of the multiple pressure supports 402 away from the limiting chambers 401 are fixedly connected to the lifting plate 410.
[0037] Furthermore, a limiting ring 403 is fixedly connected to the upper part of the limiting cavity 401, and an anti-detachment plate 404 with a cross-sectional area larger than itself is fixedly connected to the end of the pressure support 402 near the transfer cavity 400. The limiting ring 403 is used to limit the anti-detachment plate 404 to prevent the pressure support 402 from falling out of the limiting cavity 401.
[0038] When the airbag 300 is compressed, the gas inside it passes through the first air tube 102 and the second air tube 103 into the transfer chamber 400, which increases the air pressure inside the transfer chamber 400. The pressure support 402 is then affected by the expansion force of the gas at the bottom of the anti-detachment plate 404 and rises. Multiple rising pressure supports 402 drive the lifting plate 410 to rise, thereby lifting the fish tail part that is transported to the top of the lifting plate 410, so that the thin scales of the fish tail can also be scraped off by the scale scraper 201.
[0039] The working principle of automated transportation equipment will be explained in more detail below: First, fish products are placed on top of the short conveyor roller from the inlet 104. The rotating short conveyor roller drives the fish to move towards the long conveyor roller 101. When the short conveyor roller drives the fish products to the top of the lifting plate 410, the limiting plate 210 drives the drive roller 200 to move downward, so that the drive roller 200 moves closer to the fish.
[0040] When the rotating short conveyor roller drives the fish to move, the top of the control box 120 is slightly lower than the top of the short conveyor roller, thus preventing the control box 120 from obstructing the fish's forward movement. During the movement of the fish driven by the short conveyor roller, the fish tail faces forward along the direction of movement. When the fish tail reaches below the drive roller 200, the piston end of the hydraulic rod 212 drives the limiting plate 210 to descend. The descending limiting plate 210 causes the drive roller 200 to move closer to the tail of the fish, thus fitting the thinner tail portion.
[0041] When the hydraulic rod 212 drives the limiting plate 210 to slide down, the pressure-bearing inclined surface 221, which is in contact with the driving inclined surface 211, is driven by the descending driving inclined surface 211 to slide away from the limiting plate 210. The pressure block 220 pushes the extrusion plate 310 to slide closer to the side wall of the lifting frame 110. By reducing the space enclosed by the extrusion plate 310 and the side wall of the lifting frame 110, the airbag 300 is compressed. The gas inside it passes through the first air pipe 102 and the second air pipe 103 into the transfer chamber 400, which increases the air pressure inside the transfer chamber 400. The pressure support 402 is affected by the gas expansion force at the bottom of the anti-detachment plate 404 and rises. Multiple rising pressure supports 402 drive the lifting plate 410 to rise, thereby lifting the fish tail part delivered to the top of the lifting plate 410, so that the thin scales of the fish tail can also be scraped off by the scale scraper 201.
[0042] Through the above-mentioned process, the processing of fish and aquatic products can ensure the efficiency of fish processing, remove fish scales from the fish's body, and prevent damage to the fish.
[0043] The foregoing has shown and described the basic principles, main features, and advantages of the present invention. Those skilled in the art should understand that the present invention is not limited to the above embodiments. The embodiments and descriptions in the specification are merely preferred examples and are not intended to limit the invention. Various changes and modifications can be made to the invention without departing from its spirit and scope, and all such changes and modifications fall within the scope of the present invention as claimed. The scope of protection of the present invention is defined by the appended claims and their equivalents.
Claims
1. An automatic conveying device for aquatic product processing and production, comprising a pair of spaced installation plates (100), a plurality of long conveying rollers (101) and a plurality of pairs of short conveying rollers rotatably connected between the two installation plates (100), each pair of short conveying rollers comprising two, a height-raising frame (110) fixedly connected above the two installation plates (100), characterized in that: a height-adjustable limiting plate (210) is arranged between the height-raising frame (110) and the long conveying rollers (101), a drive roller (200) for removing fish scales is rotatably connected below the limiting plate (210), a pressure-bearing block (220) is arranged on one side of the limiting plate (210), the pressure-bearing block (220) is slidably connected with the height-raising frame (110), a gas bag (300) full of gas is arranged on the side of the pressure-bearing block (220) away from the limiting plate (210), a plurality of pairs of long conveying rollers (101) are arranged between the operation box (120), the operation box (120) is provided with a transfer cavity (400) in communication with the gas bag (300), and a lifting plate (410) is slidably connected to the top of the operation box (120), the bottom of the lifting plate (410) is in pressure balance with the inside of the transfer cavity (400). When the tail of the fish passes through the top of the lifting plate (410), the limiting plate (210) slides downward to press the gas bag (300), so as to extrude the gas inside the gas bag (300) into the transfer cavity (400), so that the lifting plate (410) drives the fish tail to be lifted up and close to the drive roller (200). The top of the operation box (120) is lower than the top of the short conveying shaft, one end of the short conveying shaft is rotatably connected with the installation plate (100), and the other end of the short conveying shaft is rotatably connected with the side wall of the operation box (120).
2. The automatic transport equipment for aquatic product processing production according to claim 1, characterized in that: The bottoms of the two ends of the limiting plate (210) are fixedly connected with rotating pins, the drive roller (200) is rotatably connected between the two rotating pins, and a plurality of scale removing plates (201) are fixedly connected to the periphery of the drive roller (200).
3. The automatic transport equipment for aquatic product processing production according to claim 1, characterized in that: A hydraulic rod (212) and a plurality of guide rods (213) are arranged above the limiting plate (210), the hydraulic rod (212) comprises a cylinder body and a piston end, the cylinder body is fixedly connected with the height-raising frame (110), the piston end is fixedly connected with the top of the limiting plate (210), one end of the guide rod (213) is fixedly connected with the top of the limiting plate (210), and the guide rod (213) is slidably connected with the height-raising frame (110), and the lifting plate (410) is adjacent to the drive roller (200).
4. The automatic transport equipment for aquatic product processing production according to claim 1, characterized in that: The scale removing plate (201) is curved, when the scale removing plate (201) is rotated to be directly below the drive roller (200), the concave side of the scale removing plate (201) points to the upstream side of the fish body movement, and the radius of the drive roller (200) gradually decreases from both ends to the middle to adapt to the shape of the fish body.
5. The automatic transport equipment for aquatic product processing production according to claim 3, characterized in that: A driving slope (211) is formed on the side of the limiting plate (210) close to the pressure-bearing block (220), a pressure-bearing slope (221) is formed on the side of the pressure-bearing block (220) close to the limiting plate (210), and the driving slope (211) and the pressure-bearing slope (221) are mutually fitted.
6. The automatic transport equipment for aquatic product processing production according to claim 1, characterized in that: 7. The automatic transport equipment for aquatic product processing production according to claim 1, characterized in that: The pressure block (220) top fixedly connected with a sliding block (230), the top of the high frame (110) is provided with a sliding slot (231), the sliding block (230) is slidably connected in the sliding slot (231), the spring (232) is arranged between the one side of the sliding block (230) and the side wall of the sliding slot (231), and the spring (232) is used to drive the sliding block (230) to slide in the sliding slot (231) and reset.
8. The automated transport apparatus for processing aquatic products according to claim 1, characterized in that: The pressure block (220) is provided with an extrusion plate (310) away from the limiting plate (210), the air bag (300) is located in the extrusion plate (310), the extrusion plate (310) is slidably connected with the side wall of the high frame (110), and the extrusion plate (310) is fixedly connected with the pressure block (220).
9. The automated transport apparatus for processing aquatic products according to claim 1, characterized in that: The air bag (300) is communicated with a first air pipe (102) on one side, the transfer cavity (400) is communicated with a second air pipe (103) on one side, the first air pipe (102) and the second air pipe (103) are communicated through a sealing hose, and the top of the transfer cavity (400) is provided with a plurality of limiting cavities (401) in communication, each limiting cavity (401) is slidably connected with a pressure support (402) in the inside, and the end, away from the limiting cavity (401), of the plurality of pressure supports (402) is fixedly connected with a lifting plate (410).
10. The automated transport apparatus for processing aquatic products according to claim 9, wherein: The limiting cavity (401) is fixedly connected with a limiting ring (403) at the upper portion, the end, close to the transfer cavity (400), of the pressure support (402) is fixedly connected with a anti-drop plate (404) with a larger cross-sectional area than itself, and the limiting ring (403) is used to limit the anti-drop plate (404) to prevent the pressure support (402) from falling off from the limiting cavity (401). The limiting cavity (401) is fixedly connected with a limiting ring (403) at the upper portion, the end, close to the transfer cavity (400), of the pressure support (402) is fixedly connected with a anti-drop plate (404) with a larger cross-sectional area than itself, and the limiting ring (403) is used to limit the anti-drop plate (404) to prevent the pressure support (402) from falling off from the limiting cavity (401).