Novel laboratory ware cleaning machine
By designing an automated laboratory vessel cleaning machine, high-pressure spray cleaning and drying functions of chemicals and clean water, the problems of low cleaning efficiency and residual water stains in laboratory vessels are solved, achieving efficient, safe and water-saving cleaning effects.
Patent Information
- Application Number
- CN202422086167.6
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- Filing Date
- 2024-08-27
- Publication Date
- 2025-07-04
- Estimated Expiration
- 2034-08-27
AI Technical Summary
The cleaning efficiency of existing laboratory vessels is low. After cleaning, the vessels are easily left to dry. There are safety hazards and high labor costs when they are left to dry.
Design a laboratory vessel cleaning machine including a roller conveyor belt and a multi-function cleaning channel. Through the high-pressure spray cleaning and drying functions of chemicals and clean water, an automated cleaning process is realized and manual contact is avoided.
It improves cleaning efficiency, reduces water resource consumption, ensures that the cleaned utensils are clean and free of residual water stains, and reduces safety risks.
Smart Images
Figure CN223056333U_ABST
Abstract
Description
Technical Field
[0001] The utility model relates to the technical field of cleaning equipment, in particular to a new type of laboratory ware washing machine. Background Art
[0002] A large number of plastic laboratory wares (such as plastic test tubes, beakers, measuring cylinders, funnels, etc.) are used in laboratories for experiments, analysis, chemical reactions, separation, sampling, etc. When research becomes more and more refined and the requirements become higher and higher, the cleanliness of laboratory wares will directly affect the experimental results.
[0003] At present, most laboratory wares are still manually cleaned, and manual cleaning has the following disadvantages: low cleanliness, low cleaning efficiency, and high labor costs; solid waste such as waste gloves and masks will be generated during the manual cleaning process as protective equipment such as gloves and masks need to be worn; the chemical reagents contaminated on laboratory wares and the cleaning agents used may cause harm to the skin, eyes, etc. of the cleaning personnel; manual cleaning uses a large amount of water, wasting water. For this reason, we have proposed a new type of laboratory ware washing machine. Content of the Utility Model
[0004] The utility model is proposed to solve the disadvantages existing in the prior art, and provides a new type of laboratory ware washing machine, which solves the problems of low efficiency during cleaning and residual water stains after the wares are left to dry statically.
[0005] In order to achieve the above purpose, the utility model adopts the following technical scheme:
[0006] A new type of laboratory ware washing machine, including a roller conveyor belt, a controller is arranged on one side of the roller conveyor belt, a ware placement channel is arranged at the upper left end of the roller conveyor belt, a ware placement part is arranged in the ware placement channel, a ware chemical cleaning channel is arranged on one side of the ware placement channel, a chemical cleaning part is arranged in the ware chemical cleaning channel, a clear water flushing channel is arranged on one side of the ware chemical cleaning channel, a clear water flushing part is arranged in the clear water flushing channel, a drying channel is arranged on one side of the clear water flushing channel, a drying part is arranged in the drying channel, a chemical waste liquid collection box is arranged below the ware placement channel and the ware chemical cleaning channel, a clear water waste liquid collection box is arranged below the clear water flushing channel and the drying channel, and a cover plate is arranged above the ware placement channel.
[0007] Through the above technical solution, open the cover plate to form an open state above the vessel placement channel. Place the vessel to be cleaned in the vessel placement part and close the cover plate. Then, use the controller to control the operation of the roller conveyor belt. The roller conveyor belt first moves the vessel placement part with the vessel to the vessel chemical cleaning channel. Then, the chemical cleaning part in the vessel chemical cleaning channel performs a strong chemical cleaning on the vessel. The waste liquid or waste from the cleaning falls into the chemical waste liquid collection box for collection.
[0008] After that, the controller controls the operation of the roller conveyor belt to send the vessel after chemical cleaning into the clear water rinsing channel. The clear water rinsing part in the clear water rinsing channel performs a secondary cleaning on the vessel. The waste water from the cleaning falls into the clear water waste liquid collection box for collection.
[0009] Then, the controller controls the operation of the roller conveyor belt to send the cleaned vessel into the drying channel. The drying part is used for drying operation. Finally, the controller controls the operation of the roller conveyor belt to send the cleaned and dried vessel to the right end of the roller conveyor belt, and open the vessel placement part to take it, so as to provide an automatic cleaning function. At the same time, first perform a cleaning with chemicals, then perform two rinses with clear water to improve the cleaning efficiency, and finally dry it to avoid water stains remaining on the vessel.
[0010] Preferably, the chemical cleaning part includes a chemical annular spray pipe, which is arranged on the inner side wall of the vessel chemical cleaning channel. One side of the chemical annular spray pipe is provided with a conveying pipe 1, and one end of the conveying pipe 1 is provided with a water pump 1. In front of the vessel chemical cleaning channel, there is a chemical mixing tank. The upper side of the chemical mixing tank is provided with a tank cover, and the upper side of the tank cover is provided with a chemical adding pipe. Heaters 1 are arranged at the inner corners of the chemical mixing tank. The front side of the chemical mixing tank is provided with a temperature controller 1. The left side of the chemical mixing tank is provided with a water inlet pipe 1. The lower side of the chemical mixing tank is provided with a motor, and the shaft end of the motor is provided with a stirring rod. The stirring rod and the water pump 1 are both placed in the chemical mixing tank.
[0011] Through the above technical solution, add appropriate chemicals into the chemical mixing tank through the chemical adding pipe, then inject clear water into the chemical mixing tank through the water inlet pipe 1. Then, the temperature controller 1 controls the heater 1 to work, heating the liquid in the chemical mixing tank to a certain temperature. While heating, the motor drives the stirring rod to stir the liquid in the chemical mixing tank. After heating to the specified temperature, the water pump 1 works to pump the mixed liquid into the water pump 1 and flows into the chemical annular spray pipe, so as to perform a four-sided annular spray rinse on the vessel, thus providing a chemical rinsing function.
[0012] Preferably, the fresh water rinsing section includes a circular fresh water spraying pipeline, which is arranged on the inner side wall of the fresh water rinsing channel. One side of the circular fresh water spraying pipeline is provided with a second conveying pipe, and one end of the second conveying pipe is provided with a second water pump. In front of the fresh water rinsing channel, there is a fresh water tank. Heaters II are arranged at the inner corners of the fresh water tank. A temperature controller II is arranged on the front side of the fresh water tank. A second water inlet pipe is arranged on the left side of the fresh water tank. The second water pump is placed in the fresh water tank.
[0013] Through the above technical solution, fresh water is added into the fresh water tank through the second water inlet pipe. Then, the temperature controller II controls the heater II to work. The heater II heats the fresh water in the fresh water tank. After heating to a certain temperature, the second water pump pumps the liquid into the second conveying pipe and flows into the circular fresh water spraying pipeline, so as to perform a four-sided circular spraying rinse on the utensils, thereby providing a function of secondary fresh water rinsing.
[0014] Preferably, the drying section includes a circular air blowing duct, which is arranged on the inner side wall of the drying channel. A warm air blower is arranged in front of the drying channel. One side of the warm air blower is connected to one side of the circular air blowing duct.
[0015] Through the above technical solution, the warm air blower works, sucks air to form a heat flow and sends it into the circular air blowing duct, so as to perform a four-sided circular hot air drying on the utensils, thereby providing a drying function.
[0016] Preferably, a partition is arranged between the chemical waste liquid storage tank and the fresh water waste liquid storage tank. A waste liquid discharge pipe is arranged on the left side of the chemical waste liquid storage tank. A control valve is arranged on the outer side of the waste liquid discharge pipe. A drain pipe is arranged on the lower side of the fresh water waste liquid storage tank.
[0017] Through the above technical solution, the control valve controls the opening and closing of the waste liquid discharge pipe to provide a function of discharging the waste liquid in the chemical waste liquid storage tank. With the arrangement of the drain pipe, the drain pipe is externally connected to a hose, and the hose is inserted into the sewer drain outlet, so that the waste liquid in the fresh water waste liquid storage tank can be directly discharged into the sewer.
[0018] Preferably, the utensil placing section includes a placing frame, which is arranged on the upper side of the roller conveyor belt. A top cover is arranged on the upper side of the placing frame. A limiting component is arranged on the upper side of the top cover, and the limiting component is used for limiting between the top cover and the placing frame.
[0019] Through the above technical solution, with the limitation of the limiting component, the top cover can change the capacity in the placing frame.
[0020] Preferably, the limiting component includes a U-shaped frame disposed on the upper side of the top cover. A threaded rod is arranged inside the U-shaped frame. A rubber sleeve is provided in the middle of the outer side of the threaded rod. Moving plates are arranged at both ends of the outer side of the threaded rod. A limiting block is arranged on one side of the moving plate.
[0021] Through the above technical solution, lifting the U-shaped frame can separate the top cover from the placement frame. After placing a certain amount of utensils into the placement frame, lift the U-shaped frame again to combine the top cover with the placement frame. The lower side of the top cover fits against the top of the utensils. Then rotate the rubber sleeve, and the rubber sleeve drives the threaded rod to rotate on the U-shaped frame. The threaded rod rotates to drive the moving plate through thread transmission, and the moving plate drives the limiting block to move. The limiting block fits against the inner wall of the placement frame for fixation.
[0022] In summary, for this utility model, open the cover plate to form an open state above the utensil placement channel. Place the utensils to be cleaned in the utensil placement part and close the cover plate. Then use the controller to control the roller conveyor belt to work. The roller conveyor belt first moves the utensil placement part with the utensils to the utensil chemical cleaning channel. Then the chemical cleaning part in the utensil chemical cleaning channel performs a strong chemical cleaning on the utensils. The waste liquid or waste from the cleaning falls into the chemical waste liquid collection box for collection.
[0023] After that, the controller controls the roller conveyor belt to work, sending the utensils after chemical cleaning into the clear water rinsing channel. The clear water rinsing part in the clear water rinsing channel performs a secondary cleaning on the utensils. The waste water from the cleaning falls into the clear water waste liquid collection box for collection.
[0024] Then the controller controls the roller conveyor belt to work, sending the cleaned utensils into the drying channel. The drying part is used for drying operation. Finally, the controller controls the roller conveyor belt to work, sending the cleaned and dried utensils to the right end of the roller conveyor belt. Open the utensil placement part to take them, thus providing an automatic cleaning function. At the same time, first perform a cleaning with chemicals, then perform two rinses with clear water to improve the cleaning efficiency, and finally dry them, thereby avoiding water stains remaining on the utensils. This new laboratory utensil cleaning machine has a built-in drying function, high cleaning efficiency, high cleanliness, does not require manual contact, high safety, adopts a high-pressure spray cleaning method, and is more water-saving. BRIEF DESCRIPTION OF THE DRAWINGS
[0025] Figure 1 is an exploded structural schematic diagram of the present utility model;
[0026] Figure 2 is a front axonometric structural schematic diagram of the present utility model;
[0027] Figure 3 is a front axonometric sectional view of the present utility model taken along one direction;
[0028] Figure 4This is the structural schematic diagram of the second front axonometric section of the utility model;
[0029] Figure 5 This is the structural schematic diagram of the utensil placement part of the utility model;
[0030] Figure 6 This is the exploded structural schematic diagram of the utensil placement part of the utility model.
[0031] In the figure: 1. Roller conveyor belt; 2. Controller; 3. Utensil placement channel; 4. Utensil placement part; 41. Placement frame; 42. Top cover; 43. Limit component; 431. U-shaped frame; 432. Threaded rod; 433. Rubber sleeve; 434. Moving plate; 435. Limit block; 5. Utensil medicine cleaning channel; 6. Clear water flushing channel; 7. Drying channel; 8. Medicine waste liquid collection box; 9. Clear water waste liquid collection box; 10. Cover plate; 11. Medicine annular spray pipe; 12. Delivery pipe 1; 13. Water pump 1; 14. Medicine mixing box; 15. Box cover; 16. Medicine adding pipe; 17. Heater 1; 18. Temperature controller 1; 19. Water inlet pipe 1; 20. Motor; 21. Stirring rod; 22. Clear water annular spray pipe; 23. Delivery pipe 2; 24. Water pump 2; 25. Clear water tank; 26. Heater 2; 27. Temperature controller 2; 28. Water inlet pipe 2; 29. Annular air blowing air duct; 30. Hot air blower; 31. Partition board; 32. Waste liquid discharge pipe; 33. Control valve; 34. Drain pipe. Specific embodiments
[0032] Next, the technical solutions in the embodiments of the present utility model will be clearly and completely described in conjunction with the accompanying drawings in the embodiments of the present utility model. Obviously, the described embodiments are only a part of the embodiments of the present utility model, rather than all the embodiments.
[0033] Such as Figures 1-4As shown in the figure, a new type of laboratory ware washing machine includes a roller conveyor belt 1. On one side of the roller conveyor belt 1, there is a controller 2. At the upper left end of the roller conveyor belt 1, there is a ware placement channel 3. Inside the ware placement channel 3, there is a ware placement part 4. On one side of the ware placement channel 3, there is a ware chemical cleaning channel 5. Inside the ware chemical cleaning channel 5, there is a chemical cleaning part. The chemical cleaning part includes a chemical annular spray pipe 11, which is arranged on the inner side wall of the ware chemical cleaning channel 5. On one side of the chemical annular spray pipe 11, there is a conveying pipe 12. At one end of the conveying pipe 12, there is a water pump 13. In front of the ware chemical cleaning channel 5, there is a chemical mixing tank 14. On the upper side of the chemical mixing tank 14, there is a tank cover 15. On the upper side of the tank cover 15, there is a chemical adding pipe 16. At the inner corners of the chemical mixing tank 14, there are heaters 17. On the front side of the chemical mixing tank 14, there is a temperature controller 18. On the left side of the chemical mixing tank 14, there is a water inlet pipe 19. On the lower side of the chemical mixing tank 14, there is a motor 20. At the shaft end of the motor 20, there is a stirring rod 21. The stirring rod 21 and the water pump 13 are both placed inside the chemical mixing tank 14.
[0034] On one side of the ware chemical cleaning channel 5, there is a clean water rinsing channel 6. Inside the clean water rinsing channel 6, there is a clean water rinsing part. The clean water rinsing part includes a clean water annular spray pipe 22, which is arranged on the inner side wall of the clean water rinsing channel 6. On one side of the clean water annular spray pipe 22, there is a conveying pipe 23. At one end of the conveying pipe 23, there is a water pump 24. In front of the clean water rinsing channel 6, there is a clean water tank 25. At the inner corners of the clean water tank 25, there are heaters 26. On the front side of the clean water tank 25, there is a temperature controller 27. On the left side of the clean water tank 25, there is a water inlet pipe 28. The water pump 24 is placed inside the clean water tank 25.
[0035] On one side of the clean water rinsing channel 6, there is a drying channel 7. Inside the drying channel 7, there is a drying part. The drying part includes an annular air blowing duct 29, which is arranged on the inner side wall of the drying channel 7. In front of the drying channel 7, there is a warm air blower 30. One side of the warm air blower 30 is connected to one side of the annular air blowing duct 29.
[0036] Below the ware placement channel 3 and the ware chemical cleaning channel 5, there is a chemical waste liquid collection box 8. Below the clean water rinsing channel 6 and the drying channel 7, there is a clean water waste liquid collection box 9. On the upper side of the ware placement channel 3, there is a cover plate 10. Between the chemical waste liquid collection box 8 and the clean water waste liquid collection box 9, there is a partition 31. On the left side of the chemical waste liquid collection box 8, there is a waste liquid discharge pipe 32. Outside the waste liquid discharge pipe 32, there is a control valve 33. On the lower side of the clean water waste liquid collection box 9, there is a drain pipe 34.
[0037] In this embodiment, the cover plate 10 is opened to form an open state above the utensil placement channel 3. The utensil to be cleaned is placed in the utensil placement part 4, and the cover plate 10 is closed. Then, the controller 2 is used to control the operation of the roller conveyor belt 1. The roller conveyor belt 1 first moves the utensil placement part 4 with the utensil to the utensil chemical cleaning channel 5. Then, an appropriate chemical is added into the chemical mixing tank 14 through the chemical addition pipe 16. Next, clear water is injected into the chemical mixing tank 14 through the first water inlet pipe 19. Then, the first temperature controller 18 controls the operation of the first heater 17 to heat the liquid in the chemical mixing tank 14 to a certain temperature. While heating, the motor 20 drives the stirring rod 21 to stir the liquid in the chemical mixing tank 14. After heating to the specified temperature, the first water pump 13 operates to pump the mixed liquid into the first water pump 13 and flow into the chemical annular spray pipe 11, so as to perform a four-sided annular spray cleaning on the utensil, and perform a strong chemical cleaning. The waste liquid or waste material from the cleaning falls into the chemical waste liquid collection box 8 for collection.
[0038] After that, the controller 2 controls the operation of the roller conveyor belt 1 to send the utensil after chemical cleaning into the clear water rinsing channel 6. Clear water is added into the clear water tank 25 through the second water inlet pipe 28. Then, the second temperature controller 27 controls the operation of the second heater 26, and the second heater 26 heats the clear water in the clear water tank 25. After heating to a certain temperature, the second water pump 24 pumps the liquid into the second conveying pipe 23 and flows into the clear water annular spray pipe 22, so as to perform a four-sided annular spray cleaning on the utensil, and perform a secondary rinsing on the utensil. The waste water from the cleaning falls into the clear water waste liquid collection box 9 for collection.
[0039] Then, the controller 2 controls the operation of the roller conveyor belt 1 to send the cleaned utensil into the drying channel 7. The warm air blower 30 operates, and the suction forms a heat flow and is sent into the annular air blowing air pipe 29, so as to perform a four-sided annular hot air drying on the utensil. Finally, the controller 2 controls the operation of the roller conveyor belt 1 to send the cleaned and dried utensil to the right end of the roller conveyor belt 1, and the utensil placement part 4 is opened for taking.
[0040] As Figures 5-6 shown, the utensil placement part 4 includes a placement frame 41. The placement frame 41 is arranged on the upper side of the roller conveyor belt 1. A top cover 42 is arranged on the upper side of the placement frame 41. Both the placement frame 41 and the top cover 42 are arranged in a mesh structure. A limiting component 43 is arranged on the upper side of the top cover 42. The limiting component 43 includes a U-shaped frame 431. The U-shaped frame 431 is arranged on the upper side of the top cover 42. A threaded rod 432 is arranged inside the U-shaped frame 431. A rubber sleeve 433 is arranged in the middle of the outer side of the threaded rod 432. Moving plates 434 are arranged at both ends of the outer side of the threaded rod 432. A limiting block 435 is arranged on one side of the moving plate 434.
[0041] In this embodiment, the hand-held U-shaped frame 431 can separate the top cover 42 from the placement frame 41. After placing a certain amount of utensils into the placement frame 41, the hand-held U-shaped frame 431 combines the top cover 42 with the placement frame 41 again. The lower side of the top cover 42 fits against the top of the utensils. Then, the rubber sleeve 433 is rotated. The rubber sleeve 433 drives the threaded rod 432 to rotate on the U-shaped frame 431. The threaded rod 432 rotates to drive the moving plate 434 through threaded transmission. The moving plate 434 drives the limiting block 435 to move. The limiting block 435 fits against the inner wall of the placement frame 41 for fixation.
[0042] It should be noted that a thermostat is a series of automatic control components that, according to the temperature change of the working environment, undergo physical deformation inside the switch, thereby generating certain special effects and producing on or off actions. Or electronic components provide temperature data to the circuit based on different working principles at different temperatures for the circuit to collect temperature data.
[0043] Both the first water pump 13 and the second water pump 24 are booster pumps. A booster pump is a pump used to increase pressure.
[0044] The chemical agent annular spray pipe 11 and the clean water annular spray pipe 22 are both composed of an annular pipe and a high-pressure nozzle. A high-pressure nozzle is a device that uses high pressure to form a high-speed jet flow of fluid through the nozzle outlet. Its working principle is to increase the pressure of the fluid so that it generates high-speed flow when flowing through the nozzle outlet. This high-speed flowing fluid has greater kinetic energy, thus forming a high-speed jet flow, generating impact force and shear force to achieve the required treatment effect. The spraying effect of the high-pressure nozzle is mainly determined by factors such as the speed of the fluid, the shape of the nozzle outlet, and the density of the fluid. The higher the fluid speed, the greater the impact force and shear force of the jet flow, and the shape of the nozzle outlet affects the diffusion degree and direction of the jet flow. Different nozzle shapes can achieve different spraying effects.
[0045] The above is only the preferred specific embodiment of the present invention, but the protection scope of the present invention is not limited thereto. Any person skilled in the art within the technical scope disclosed by the present invention, according to the technical solution and the inventive concept of the present invention, makes equivalent substitutions or changes, and all should be covered within the protection scope of the present invention.
Claims
1. A new type of laboratory ware washing machine, including a roller conveyor belt (1), and a controller (2) is arranged on one side of the roller conveyor belt (1), characterized in that, On the upper left end of the roller conveyor belt (1), there is a utensil placement channel (3). Inside the utensil placement channel (3), there is a utensil placement part (4). On one side of the utensil placement channel (3), there is a utensil medicine cleaning channel (5). Inside the utensil medicine cleaning channel (5), there is a medicine cleaning part. On one side of the utensil medicine cleaning channel (5), there is a clear water rinsing channel (6). Inside the clear water rinsing channel (6), there is a clear water rinsing part. On one side of the clear water rinsing channel (6), there is a drying channel (7). Inside the drying channel (7), there is a drying part. Below the utensil placement channel (3) and the utensil medicine cleaning channel (5), there is a medicine waste liquid collection box (8). Below the clear water rinsing channel (6) and the drying channel (7), there is a clear water waste liquid collection box (9). On the upper side of the utensil placement channel (3), there is a cover plate (10).
2. The novel laboratory ware washing machine according to claim 1, characterized in that, The medicine cleaning part includes a medicine annular spray pipe (11). The medicine annular spray pipe (11) is arranged on the inner side wall of the utensil medicine cleaning channel (5). On one side of the medicine annular spray pipe (11), there is a conveying pipe one (12). One end of the conveying pipe one (12) is provided with a water pump one (13). In front of the utensil medicine cleaning channel (5), there is a medicine mixing box (14). On the upper side of the medicine mixing box (14), there is a box cover (15). On the upper side of the box cover (15), there is a medicine adding pipe (16). At the inner corners of the medicine mixing box (14), there are heaters one (17). On the front side of the medicine mixing box (14), there is a temperature controller one (18). On the left side of the medicine mixing box (14), there is a water inlet pipe one (19). On the lower side of the medicine mixing box (14), there is a motor (20). At the shaft end of the motor (20), there is a stirring rod (21). Both the stirring rod (21) and the water pump one (13) are placed inside the medicine mixing box (14).
3. A novel laboratory ware washing machine according to claim 1, characterized in that, The clear water rinsing part includes a clear water annular spray pipe (22). The clear water annular spray pipe (22) is arranged on the inner side wall of the clear water rinsing channel (6). On one side of the clear water annular spray pipe (22), there is a conveying pipe two (23). One end of the conveying pipe two (23) is provided with a water pump two (24). In front of the clear water rinsing channel (6), there is a clear water tank (25). At the inner corners of the clear water tank (25), there are heaters two (26). On the front side of the clear water tank (25), there is a temperature controller two (27). On the left side of the clear water tank (25), there is a water inlet pipe two (28). The water pump two (24) is placed inside the clear water tank (25).
4. A novel laboratory ware washing machine according to claim 1, characterized in that, The drying part includes an annular air blowing air pipe (29). The annular air blowing air pipe (29) is arranged on the inner side wall of the drying channel (7). In front of the drying channel (7), there is a warm air blower (30). One side of the warm air blower (30) is connected to one side of the annular air blowing air pipe (29).
5. A novel laboratory ware washing machine according to claim 1, characterized in that, A partition plate (31) is arranged between the chemical waste liquid storage tank (8) and the clean water waste liquid storage tank (9). A waste liquid discharge pipe (32) is arranged on the left side of the chemical waste liquid storage tank (8), a control valve (33) is arranged on the outer side of the waste liquid discharge pipe (32), and a drain pipe (34) is arranged on the lower side of the clean water waste liquid storage tank (9).
6. The novel laboratory ware washing machine according to claim 1, wherein, The vessel placing part (4) includes a placing frame (41). The placing frame (41) is arranged on the upper side of the roller conveyor belt (1). A top cover (42) is arranged on the upper side of the placing frame (41), and a limiting component (43) is arranged on the upper side of the top cover (42). The limiting component (43) is used for limiting between the top cover (42) and the placing frame (41).
7. A novel laboratory ware washing machine according to claim 6, characterized in that, The limiting component (43) includes a U-shaped frame (431). The U-shaped frame (431) is arranged on the upper side of the top cover (42). A threaded rod (432) is arranged inside the U-shaped frame (431). A rubber sleeve (433) is arranged in the middle of the outer side of the threaded rod (432). Moving plates (434) are arranged at both ends of the outer side of the threaded rod (432). A limiting block (435) is arranged on one side of the moving plate (434).