Part defect detection device

Abstract

The utility model discloses a part defect detection device, which relates to the technical field of part manufacturing and comprises a detection base, a part detection mechanism is arranged on the front side of the top of the detection base, a lifting mechanism is arranged on the rear side of the top of the detection base, and a recovery mechanism is arranged on the rear side of the detection base. A motor groove is formed in the detection base, a servo motor is fixedly installed in an inner cavity of the motor groove, a gear is fixedly installed on an output shaft of the servo motor, the part detection mechanism comprises a movable ring, the movable ring is fixedly installed at the top of the detection base, and an outer gear ring is fixedly installed below the outer wall of the movable ring. According to the utility model, through the mutual cooperation of the movable ring, the outer gear ring, the part positioning mechanism, the gear and the liftable detection mechanism, the inner hole detection of the shaft sleeve part is faster and more efficient, the detection efficiency and the detection quality are improved, and defective parts with unqualified inner hole diameters are prevented from flowing into the market.

Description

Technical Field

[0001] This utility model relates to the field of parts manufacturing technology, and specifically to a parts defect detection device. Background Technology

[0002] Internal bores are widely present in various bushing-type parts and play a crucial role in their operation. To ensure the normal use of these parts, maintain their reliability, and prevent defects in the internal bore's dimensions, surface structure, etc., from affecting their quality and service life, defect detection of the internal bore is necessary. However, existing technologies have the following problems:

[0003] Because existing inspection methods mostly rely on manual inspection of the inner holes of bushing parts to determine whether they are up to standard, the inspection efficiency is low and the quality is poor, making it easy to miss parts and allow unqualified parts to pass inspection, posing a significant safety hazard. In addition, existing methods for inspecting the inner holes of bushing parts require the collection and recycling of parts with incorrect inner hole dimensions, wasting considerable manual time. Utility Model Content

[0004] This invention provides a part defect detection device to solve the problems mentioned in the background art.

[0005] To solve the above-mentioned technical problems, the technical solution adopted by this utility model is as follows:

[0006] A component defect detection device includes a detection base, a component detection mechanism on the top front side of the detection base, a lifting mechanism on the top rear side of the detection base, a retraction mechanism on the rear side of the detection base, a motor slot in the detection base, a servo motor fixedly installed in the inner cavity of the motor slot, a gear fixedly installed on the output shaft of the servo motor, a component detection mechanism including a movable ring fixedly installed on the top of the detection base, an external gear ring fixedly installed on the lower outer wall of the movable ring, the external gear ring meshing with the gear, four component positioning mechanisms arranged in a circular array on the top of the movable ring, a fixed base in the inner ring of the movable ring, the bottom of the fixed base fixedly connected to the top of the detection base, a vertical plate fixedly installed on the top of the fixed base, and an electric push rod fixedly installed on the rear side of the vertical plate.

[0007] A further improvement of this utility model is that: each of the four part positioning mechanisms includes two side boxes, a placement plate is fixedly installed below the opposite surfaces of the two side boxes, a guide inclined plate is fixedly installed on the side of the placement plate away from the center of the movable ring, two springs are fixedly installed on the opposite surfaces of the inner walls of the two side boxes, and a pressure plate is fixedly installed on the other end of the springs, and an arc-shaped clamping block is fixedly installed on the opposite surfaces of the two pressure plates, the opposite ends of the two arc-shaped clamping blocks respectively penetrate to the opposite surfaces of the two side boxes, the opposite surfaces of the two side boxes are designed with arc edges, and a guide plate is fixedly installed on the top of the two arc-shaped clamping blocks.

[0008] A further improvement of this utility model is that: a door-shaped upright plate is fixedly installed on the top of the two side upright boxes, and an infrared transmitter is fixedly installed on the side of the door-shaped upright plate away from the center of the movable ring at the horizontal position.

[0009] A further improvement of this utility model is that: each of the four placement plates has a sensing hole at the top center, and each of the four sensing holes has a mounting groove on the inner opposite surface of the inner ring. An infrared transmitter II is fixedly installed in the inner cavity of one mounting groove, and an infrared receiver II is fixedly installed in the inner cavity of the other mounting groove.

[0010] A further improvement of the present invention is that the lifting mechanism includes a portal frame, a drive column is fixedly installed at the top of the horizontal section of the portal frame, a sliding groove is provided on the front side of the drive column, a motor is fixedly installed at the top of the drive column, the output shaft of the motor passes through the inner cavity of the sliding groove and is fixedly installed with a threaded rod, a lifting plate is threadedly installed on the outer wall of the threaded rod, the front end of the lifting plate passes through the front side of the drive column and is fixedly installed with an extension plate, and a detection mechanism is provided at the bottom of the extension plate.

[0011] A further improvement of this utility model is that: a feeding sloping plate is fixedly installed on the top rear side of the detection base, the feeding sloping plate is located between two vertical points of the portal frame, side guard plates are fixedly installed on both the left and right sides of the feeding sloping plate, the front end of the feeding sloping plate overlaps with the side of the movable ring, and an infrared receiver is fixedly installed on the front side of the horizontal position of the portal frame, the infrared receiver and four infrared transmitters are all located on the same horizontal line.

[0012] A further improvement of the present invention is that the recycling mechanism includes a U-shaped plate, and a collection drawer is slidably installed in the inner cavity of the U-shaped plate, the collection drawer being located below the rear end of the discharge inclined plate.

[0013] A further improvement of this utility model's technical solution is that: the detection mechanism includes a fixed column, which is fixedly installed at the bottom of the extension plate. The fixed column is located directly above one of the four sensing holes. A threaded column one is fixedly installed at the bottom of the fixed column, a threaded column two is fixedly installed at the bottom of the threaded column one, a threaded column three is fixedly installed at the bottom of the threaded column two, and a hanging rod is fixedly installed at the bottom of the threaded column three. A fixed cylinder three is threadedly installed on the outer wall of the threaded column one, a fixed cylinder two is threadedly installed on the outer wall of the threaded column two, and a fixed cylinder one is threadedly installed on the outer wall of the threaded column three. The fixed cylinder three is sleeved on the outer wall of the fixed cylinder two, the fixed cylinder two is sleeved on the outer wall of the fixed cylinder one, and the fixed cylinder is sleeved on the outer wall of the hanging rod at the bottom of the threaded column three.

[0014] Due to the adoption of the above technical solution, the technological progress achieved by this utility model compared to the prior art is as follows:

[0015] This utility model provides a part defect detection device. Through the cooperation of a movable ring, an external gear ring, a part positioning mechanism, gears, and a liftable detection mechanism, the internal hole detection of bushing-type parts is made faster and more efficient, improving detection efficiency and quality, and preventing defective parts with unqualified internal hole diameters from entering the market.

[0016] This utility model provides a part defect detection device. Through the cooperation of an electric push rod, a feeding ramp, and a recycling mechanism, parts with unqualified inner diameters can be pushed by the electric push rod through the feeding ramp and quickly enter the recycling mechanism for centralized recycling, reducing the manual picking steps and saving manpower. Attached Figure Description

[0017] Figure 1 This is a schematic diagram of the overall structure of this utility model;

[0018] Figure 2 This is a schematic diagram of the detection mechanism of the present invention.

[0019] Figure 3 This is a schematic diagram of the part positioning mechanism of this utility model.

[0020] Figure 4 This is a top view of the placement plate of the present invention.

[0021] Figure 5 This is a schematic diagram of the lifting mechanism and the recovery mechanism of this utility model.

[0022] Figure 6 This is a schematic diagram of the detection mechanism of the present invention.

[0023] In the diagram: 1. Detection base; 11. Motor slot; 111. Servo motor; 112. Gear; 12. Unloading ramp; 121. Side guard plate; 2. Part detection mechanism; 21. Movable ring; 22. External gear ring; 23. Part positioning mechanism; 231. Side stand box; 232. Placement plate; 2321. Sensing hole; 2322. Mounting slot; 2323. Infrared transmitter II; 2324. Infrared receiver II; 233. Guide ramp; 234. Spring; 235. Pressure plate; 236. Arc-shaped clamp; 237. Wire guide plate; 238. Door-shaped upright plate; 239. Infrared transmitter 1; 24. Fixed base; 25. Upright plate; 26. Electric push rod; 3. Lifting mechanism; 31. Gate-shaped bracket; 32. Slide rail; 33. Motor; 34. Threaded rod; 35. Lifting plate; 36. Extension plate; 37. Detection mechanism; 371. Fixed column; 372. Threaded column 1; 373. Threaded column 2; 374. Threaded column 3; 375. Fixed cylinder 1; 376. Fixed cylinder 2; 377. Fixed cylinder 3; 38. Infrared receiver 1; 39. Drive column; 4. Recycling mechanism; 41. U-shaped plate; 42. Collection drawer. Detailed Implementation

[0024] To make the technical means, creative features, objectives and effects of this utility model easier to understand

[0025] Understood. The present invention will now be further described in conjunction with specific implementation methods.

[0026] like Figure 1 , Figure 2 , Figure 3As shown, this utility model provides a part defect detection device, including a detection base 1, a part detection mechanism 2 arranged on the front top of the detection base 1, a lifting mechanism 3 arranged on the rear top of the detection base 1, and a retraction mechanism 4 arranged on the rear side of the detection base 1. The detection base 1 has a motor slot 11, and a servo motor 111 is fixedly installed in the inner cavity of the motor slot 11. A gear 112 is fixedly installed on the output shaft of the servo motor 111. The part detection mechanism 2 includes a movable ring 21, which is fixedly installed on the top of the detection base 1. An external gear ring 22 is fixedly installed on the lower outer wall of the movable ring 21 and meshes with the gear 112. Four part positioning mechanisms 23 are arranged in a circular array on the top of the movable ring 21. A fixed base 24 is arranged on the inner ring of the movable ring 21. The bottom of the fixed base 24 is fixedly connected to the top of the detection base 1. A vertical plate 25 is fixedly installed on the top of the fixed base 24. An electric push rod 26 is fixedly installed on the rear side. Each of the four part positioning mechanisms 23 includes two side boxes 231. A placement plate 232 is fixedly installed below the opposite surface of the two side boxes 231. A guide inclined plate 233 is fixedly installed on the side of the placement plate 232 away from the center of the movable ring 21. Two springs 234 are fixedly installed on the opposite inner walls of the two side boxes 231. A pressure plate 235 is fixedly installed on the other end of the springs 234. An arc-shaped clamping block 236 is fixedly installed on the opposite surface of the two pressure plates 235. The opposite ends of the two arc-shaped clamping blocks 236 pass through to the opposite surface of the two side boxes 231. The opposite surface of the two side boxes 231 is designed with arc edges. A wire plate 237 is fixedly installed on the top of the two arc-shaped clamping blocks 236. A door-shaped upright plate 238 is fixedly installed on the top of the two side boxes 231. An infrared emitter 239 is fixedly installed on the horizontal side of the door-shaped upright plate 238 away from the center of the movable ring 21.

[0027] During testing, the circular perforated part (like a bushing) is aligned with the two arc-shaped clamping blocks 236 included in the four part positioning mechanisms 23 and inserted downwards. Guided by the guide plate 237, the part is secured between the two arc-shaped clamping blocks 236. The two arc-shaped clamping blocks 236 compress the spring 234 within the two side boxes 231 using pressure plates 235. The elastic pressure generated by the spring 234 temporarily clamps the part at the center of the top of the placement plate 232. Then, the servo motor 111 in the motor slot 11 is activated to drive the gear 112 to rotate, engaging with the outer gear ring 22 on the outer wall of the movable ring 21. Engaging the mechanism drives the overall movable ring 21 to rotate, thereby causing the four fixed part positioning mechanisms 23 to rotate and move one by one to the direction of the lifting mechanism 3. Whenever the infrared rays emitted by the infrared emitter 239 on the horizontal side of the portal plate 238 included in one of the part positioning mechanisms 23 are received by the infrared receiver 38 on the horizontal front side of the portal bracket 31, the infrared receiver 38 can generate an electrical signal to the servo motor 111. The servo motor 111 with its own encoder controls the rotation of the stop gear 112, so that the part positioning mechanism 23 at the top of the movable ring 21 stops at the front side of the portal bracket 31.

[0028] like Figure 4 , Figure 5 As shown, each of the four placement plates 232 has a sensing hole 2321 at its top center. The inner rings of the four sensing holes 2321 have mounting grooves 2322 on opposite sides. An infrared transmitter 2323 is fixedly installed in the inner cavity of one mounting groove 2322, and an infrared receiver 2324 is fixedly installed in the inner cavity of the other mounting groove 2322. The lifting mechanism 3 includes a portal frame 31. A drive column 39 is fixedly installed at the top of the horizontal section of the portal frame 31. A sliding groove 32 is provided on the front side of the drive column 39. A motor 33 is fixedly installed at the top of the drive column 39. The output shaft of the motor 33 passes through the inner cavity of the sliding groove 32 and is fixedly installed with a threaded rod 34. A lifting plate 35 is threaded onto the outer wall of the threaded rod 34. The front end extends to the front side of the drive column 39 and is fixedly installed with an extension plate 36. The bottom of the extension plate 36 is provided with a detection mechanism 37. The top rear side of the detection base 1 is fixedly installed with a feeding ramp 12. The feeding ramp 12 is located between two vertical points of the portal bracket 31. Side guard plates 121 are fixedly installed on both the left and right sides of the feeding ramp 12. The front end of the feeding ramp 12 overlaps with the side of the movable ring 21. An infrared receiver 38 is fixedly installed on the front side of the horizontal position of the portal bracket 31. The infrared receiver 38 and four infrared transmitters 239 are all located on the same horizontal line. The recycling mechanism 4 includes a U-shaped plate 41. A collection drawer 42 is slidably installed in the inner cavity of the U-shaped plate 41. The collection drawer 42 is located below the rear end of the feeding ramp 12.

[0029] By activating the motor 33 above the drive column 39 at the top of the portal bracket 31, the threaded rod 34 in the slide groove 32 can be rotated. The threaded connection between the threaded rod 34 and the lifting plate 35 drives the extension plate 36 to lower the detection mechanism 37. When the inner diameter of the part is within acceptable limits, the detection mechanism 37, positioned directly above the inner diameter, will pass through the inner diameter and insert into the sensing hole 2321, blocking the infrared rays emitted by the second infrared transmitter 2323 to the second infrared receiver 2324. This is considered acceptable. After the detection mechanism 37 rises and resets, the movable ring 21 can be driven to rotate again to detect the next part fixed by the part positioning mechanism 23. When the inner diameter of the part is small, the detection mechanism 37 cannot pass through the inner diameter of the part normally. The hole enters the sensing hole 2321, thus failing to block the infrared receiver 2324 from receiving the infrared rays emitted by the infrared transmitter 2323. This is considered unqualified, and the infrared receiver 2324 sends an electrical signal to the electric push rod 26, thereby activating the electric push rod 26 with its built-in signal receiving module. By moving the output end backward, the part is pushed backward. With the elastic clamping of the arc-shaped clamping block 236, the part can be smoothly pushed out. After passing through the guide ramp 233, it falls onto the unloading ramp 12, and is then placed to the sides by the side guard plate 121. Finally, it falls through the inclined unloading ramp 12 into the collection drawer 42 inside the U-shaped plate 41 for centralized collection. Afterward, the collection drawer 42 can be pulled out for processing.

[0030] like Figure 6 As shown, the detection mechanism 37 includes a fixed column 371, which is fixedly installed at the bottom of the extension plate 36. The fixed column 371 is located directly above one of the four sensing holes 2321. A threaded column 1 372 is fixedly installed at the bottom of the fixed column 371. A threaded column 2 373 is fixedly installed at the bottom of the threaded column 1 372. A threaded column 374 is fixedly installed at the bottom of the threaded column 2 373. A hanging rod is fixedly installed at the bottom of the threaded column 374. A fixed cylinder 377 is threadedly installed on the outer wall of the threaded column 1 372. A fixed cylinder 2 376 is threadedly installed on the outer wall of the threaded column 2 373. A fixed cylinder 1 375 is threadedly installed on the outer wall of the threaded column 374. The fixed cylinder 377 is sleeved on the outer wall of the fixed cylinder 2 376. The fixed cylinder 2 376 is sleeved on the outer wall of the fixed cylinder 1 375. The fixed cylinder 1 375 is sleeved on the outer wall of the hanging rod at the bottom of the threaded column 374.

[0031] The inspection mechanism 37 includes switchable diameter sizes. The smallest inner diameter parts can be inspected by the hanger at the bottom of the threaded column 374. Parts with slightly larger inner diameters can be inspected by threading the fixed cylinder 375 to the threaded column 374. Furthermore, by using the threaded connection between the fixed cylinder 2 376 and the threaded column 2 373, and the threaded connection between the fixed cylinder 377 and the threaded column 1 372, the device can be adapted to medium and large inner diameters, thereby improving the applicability of the inspection device.

[0032] The working principle of this defect detection device will be explained in detail below.

[0033] like Figure 1-6As shown, during testing, the circular perforated part (like a bushing) is aligned with the two arc-shaped clamping blocks 236 included in the four part positioning mechanisms 23 and inserted downwards. Guided by the guide plate 237, the part is clamped between the two arc-shaped clamping blocks 236. The two arc-shaped clamping blocks 236 compress the spring 234 within the two side boxes 231 using pressure plates 235. The elastic pressure generated by the spring 234 temporarily clamps the part at the center of the top of the placement plate 232. Then, the servo motor 111 in the motor slot 11 is activated, driving the gear 112 to rotate. The engagement of the gear 112 with the outer gear ring 22 on the outer wall of the movable ring 21 drives the entire movable ring 21 to rotate, thereby rotating the four part positioning mechanisms 23 with the parts fixed thereon. The parts are rotated and moved one by one to the direction of the lifting mechanism 3. Whenever the infrared rays emitted by the infrared emitter 239 on the horizontal side of the portal plate 238 included in one of the part positioning mechanisms 23 are received by the infrared receiver 38 on the horizontal front side of the portal bracket 31, the infrared receiver 38 sends an electrical signal to the servo motor 111. The servo motor 111 with its own encoder controls the rotation of the stop gear 112, so that the part positioning mechanism 23 at the top of the movable ring 21 stops at the front side of the portal bracket 31. At this time, by starting the motor 33 above the drive column 39 at the top of the portal bracket 31, the threaded rod 34 in the slide groove 32 can be rotated. The threaded connection between the threaded rod 34 and the lifting plate 35 can drive the extension plate 36 to move. The detection mechanism 37 descends. When the inner diameter of the part is within acceptable limits, the detection mechanism 37, positioned directly above the inner diameter, will pass through the inner diameter and insert into the sensing hole 2321 to block the infrared rays emitted by the second infrared emitter 2323 to the second infrared receiver 2324. This is considered acceptable. After the detection mechanism 37 rises and resets, the movable ring 21 can be driven to rotate again to detect the next part fixed by the part positioning mechanism 23. When the inner diameter of the part is small, the detection mechanism 37 cannot pass through the inner diameter and enter the sensing hole 2321 normally, thus failing to block the infrared rays emitted by the second infrared emitter 2323 from being received by the second infrared receiver 2324. This is considered unacceptable, and the second infrared receiver 2324 will then send an electrical signal to the electric pusher. The lever 26 activates the electric push rod 26 with its built-in signal receiving module. The output end moves backward, pushing the part backward. The curved clamping block 236 elastically holds the part, allowing it to be smoothly pushed out. After passing through the guide ramp 233, it falls onto the unloading ramp 12, and is then placed to the sides by the side guard plates 121. Finally, it falls through the inclined unloading ramp 12 into the collection drawer 42 inside the U-shaped plate 41 for centralized collection. The collection drawer 42 can be removed for processing afterward. Simultaneously, the detection mechanism 37 includes switchable diameter sizes. The smallest inner diameter part can be detected via the hanging rod at the bottom of the threaded column 374, while parts with slightly larger inner diameter parts can be detected by threading the fixed cylinder 375 to the threaded column 374.By utilizing the threaded connection between fixed cylinder 376 and threaded post 373, and the threaded connection between fixed cylinder 377 and threaded post 372, adaptation to medium and large inner hole diameters can be achieved, thereby improving the applicability of the testing device.

[0034] The present invention has been described in detail above. However, modifications or improvements can be made to it, which will be obvious to those skilled in the art. Therefore, any modifications or improvements that do not depart from the spirit of the present invention are within the protection scope of the present invention.

Claims

1. A part defect detection device, comprising a detection base (1), characterized in that: The detection base (1) has a part detection mechanism (2) on its top front side, a lifting mechanism (3) on its top rear side, and a recycling mechanism (4) on its rear side. The detection base (1) has a motor slot (11) with a servo motor (111) fixedly installed in the inner cavity of the motor slot (11). A gear (112) is fixedly installed on the output shaft of the servo motor (111). The part detection mechanism (2) includes a movable ring (21) which is fixedly installed on the detection base. (1) At the top, an external gear ring (22) is fixedly installed below the outer wall of the movable ring (21). The external gear ring (22) meshes with the gear (112). The top of the movable ring (21) is provided with four part positioning mechanisms (23) in a ring array. The inner ring of the movable ring (21) is provided with a fixed base (24). The bottom of the fixed base (24) is fixedly connected to the top of the detection base (1). The top of the fixed base (24) is fixedly installed with a vertical plate (25). An electric push rod (26) is fixedly installed on the rear side of the vertical plate (25).

2. The part defect detection device according to claim 1, characterized in that: Each of the four part positioning mechanisms (23) includes two side boxes (231). A placement plate (232) is fixedly installed below the opposite surfaces of the two side boxes (231). A guide plate (233) is fixedly installed on the side of the placement plate (232) away from the center of the movable ring (21). Two springs (234) are fixedly installed on the opposite surfaces of the inner walls of the two side boxes (231). A pressure plate (235) is fixedly installed on the other end of the springs (234). An arc-shaped clamping block (236) is fixedly installed on the opposite surfaces of the two pressure plates (235). The opposite ends of the two arc-shaped clamping blocks (236) respectively penetrate to the opposite surfaces of the two side boxes (231). The opposite surfaces of the two side boxes (231) are designed with arc edges. A guide plate (237) is fixedly installed on the top of the two arc-shaped clamping blocks (236).

3. The part defect detection device according to claim 2, characterized in that: A door-shaped upright plate (238) is fixedly installed on the top of the two side upright boxes (231), and an infrared emitter (239) is fixedly installed on the side of the door-shaped upright plate (238) away from the center of the movable ring (21).

4. The part defect detection device according to claim 2, characterized in that: Each of the four placement plates (232) has a sensing hole (2321) at the top center. Each of the four sensing holes (2321) has a mounting groove (2322) on the inner opposite side. An infrared transmitter (2323) is fixedly installed in the inner cavity of one mounting groove (2322), and an infrared receiver (2324) is fixedly installed in the inner cavity of the other mounting groove (2322).

5. A part defect detection device according to claim 1, characterized in that: The lifting mechanism (3) includes a portal frame (31), a drive column (39) is fixedly installed at the top of the horizontal position of the portal frame (31), a slide groove (32) is provided on the front side of the drive column (39), a motor (33) is fixedly installed on the top of the drive column (39), the output shaft of the motor (33) passes through the inner cavity of the slide groove (32) and a threaded rod (34) is fixedly installed thereon, a lifting plate (35) is threaded on the outer wall of the threaded rod (34), the front end of the lifting plate (35) passes through the front side of the drive column (39) and an extension plate (36) is fixedly installed thereon, and a detection mechanism (37) is provided at the bottom of the extension plate (36).

6. A part defect detection device according to claim 5, characterized in that: A feeding ramp (12) is fixedly installed on the top rear side of the detection base (1). The feeding ramp (12) is located between two vertical points of the portal frame (31). Side guard plates (121) are fixedly installed on both the left and right sides of the feeding ramp (12). The front end of the feeding ramp (12) overlaps with the side of the movable ring (21). An infrared receiver (38) is fixedly installed on the front side of the horizontal position of the portal frame (31). The infrared receiver (38) and four infrared transmitters (239) are all located on the same horizontal line.

7. A part defect detection device according to claim 6, characterized in that: The recycling mechanism (4) includes a U-shaped plate (41), and a collection drawer (42) is slidably installed in the inner cavity of the U-shaped plate (41). The collection drawer (42) is located below the rear end of the discharge ramp (12).

8. A part defect detection device according to claim 5, characterized in that: The detection mechanism (37) includes a fixed post (371), which is fixedly installed at the bottom of the extension plate (36). The fixed post (371) is located directly above one of the four sensing holes (2321). A threaded post one (372) is fixedly installed at the bottom of the fixed post (371). A threaded post two (373) is fixedly installed at the bottom of the threaded post one (372). A threaded post three (374) is fixedly installed at the bottom of the threaded post two (373). A fixed rod is fixedly installed. A fixed cylinder three (377) is threaded on the outer wall of the threaded column one (372). A fixed cylinder two (376) is threaded on the outer wall of the threaded column two (373). A fixed cylinder one (375) is threaded on the outer wall of the threaded column three (374). The fixed cylinder three (377) is sleeved on the outer wall of the fixed cylinder two (376). The fixed cylinder two (376) is sleeved on the outer wall of the fixed cylinder one (375). The fixed cylinder one (375) is sleeved on the outer wall of the rod at the bottom of the threaded column three (374).

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