An FDY spinning and stretching device

The spinning process involves heating the spinning fibers with a heating plate and a heat-conducting rod, causing them to stick together and be collected. The spinning fibers are then pulled stably using a slanted hook and a hook rod. Combined with an electric slide rail and a magnet, this method solves the problem of messy and disordered spinning, and improves the efficiency and safety of spinning and stretching.

CN224430805UActive Publication Date: 2026-06-30DALIAN LONGSHENG MASCH CO LTD

Patent Information

Authority / Receiving Office
CN · China
Patent Type
Utility models(China)
Current Assignee / Owner
DALIAN LONGSHENG MASCH CO LTD
Filing Date
2025-08-27
Publication Date
2026-06-30

AI Technical Summary

Technical Problem

During the spinning and stretching process, the disordered spinning process causes inconvenience and safety hazards, affecting the efficiency of the workflow.

Method used

The spinning process uses a heating plate and a heat-conducting rod to heat the spinning fibers, causing them to stick together and be collected. The spinning process is then stabilized by a slanted hook and a hook rod. Combined with an electric slide rail and a magnet, the spinning process achieves orderly cutting and winding of the fibers, eliminating the need for manual operation.

Benefits of technology

It achieves orderly collection and stable stretching of the spun yarn, improves work efficiency, and eliminates the safety hazards of manual operation.

✦ Generated by Eureka AI based on patent content.

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Abstract

This utility model relates to the field of spinning and stretching technology, and more particularly to an FDY spinning and stretching device. It includes a stretching plate, a pressing device disposed above the stretching plate, an immersion driving device disposed at one end of the stretching plate, and several stretching shafts rotatably disposed on one side of the stretching plate. The pressing device can discharge filaments. It also includes a hooking device and a debris-removing device. The hooking device includes a second slider. A first groove is formed through the stretching plate, and the second slider is slidably connected within the first groove. This utility model, through the arrangement of a heating plate and a heat-conducting rod, can melt the portion of the filaments in contact with the heat-conducting rod by heating, causing the filaments to adhere to the heat-conducting rod through the melted filaments. This allows the heat-conducting rod to collect the disordered filaments by rotating.
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Description

Technical Field

[0001] This utility model relates to the field of spinning and stretching technology, and in particular to an FDY spinning and stretching device. Background Technology

[0002] The spinning and stretching process is a step after polyester fibers are extruded into spun fibers at the spinning process. The spinning and stretching process is an important step to improve the physical and mechanical properties of the fibers, which can improve the stability and strength of the spinning process. After the stretching process, the fibers will be soaked.

[0003] After polyester fibers are extruded into spun fibers at the spinning device, they are collected and placed at the spinning process area for a period of time before being discharged from the spinning device. The section of spun fibers that is just discharged is in a disordered state. At this point, workers need to pull out the disordered spun fibers and cut them with the orderly spun fibers. The cut disordered spun fibers need to be collected using other devices or tools. The two steps of pulling out the disordered spun fibers and collecting them are extremely inconvenient and seriously affect the overall workflow. At the same time, after the spun fibers are cut, workers need to use hooks to catch the spun fibers and wrap them around the stretching rollers for stretching. Since the stretching rollers are rotating, this step poses a great safety hazard. Utility Model Content

[0004] In order to overcome the problems mentioned in the background art, this utility model provides an FDY spinning stretching device.

[0005] The technical solution of this utility model is as follows: an FDY spinning and stretching device, including a stretching plate, an extrusion device above the stretching plate, an immersion drive device at one end of the stretching plate, and several stretching shafts rotatably arranged on one side of the stretching plate. The extrusion device can discharge spun yarn. It also includes a hooking device and a debriding device. The hooking device includes a second slider. A first groove is opened through the stretching plate. The second slider is slidably connected in the first groove. A rotating shaft is fixedly connected to one side of the second slider. A first gear is rotatably connected to one end of the rotating shaft. An oblique hook and a hook rod for hooking spun yarn are fixedly installed on the side of the first gear away from the rotating shaft. The debriding device includes a heating plate. A racetrack-shaped groove is opened through the stretching plate. A movable shaft is movably connected in the racetrack-shaped groove. A motor is connected to one end of the movable shaft. The heating plate is detachably snapped onto the other end of the movable shaft. Several heat-conducting rods are fixedly connected to the end of the heating plate away from the movable shaft.

[0006] Preferably, the hooking device also includes an electric slide rail, an electric slide rail is provided on the stretching plate, an electric slider is slidably connected inside the electric slide rail, and a first magnet and a second magnet are respectively fixed to the opposite end of the second slider and the electric slider.

[0007] Preferably, the hooking device also includes a cutting blade, a second groove is provided on one side of the stretching plate, a slide plate is slidably connected in the second groove, the cutting blade is fixedly connected to the end of the slide plate away from the stretching plate, and an elastic plate is fixedly connected to the top of the slide plate, with the elastic plate in contact with the rotating shaft.

[0008] Preferably, the hooking device also includes a first rack, and two first racks are installed on one side of the stretching plate via a fixing plate. The first racks are located above and below the two ends of the electric slide rail, respectively.

[0009] Preferably, the impurity removal device further includes a first slider, a first slider that is slidably connected in a first groove and slidably in contact with a second slider, a second rack fixedly connected to the side of the first slider away from the second slider, a second gear that is rotatably connected to the stretching plate body meshing below the second rack, a third rack meshing below the second gear, a sliding frame that is slidably connected to the stretching plate body fixedly connected to the bottom of the third rack, a motor fixedly connected inside the sliding frame, a push rod that is slidably connected to the stretching plate body fixedly connected to one side of the sliding frame, and a cylinder that is fixedly connected to the stretching plate body fixedly connected to the bottom side of the push rod.

[0010] Preferably, the impurity removal device further includes an elastic wedge block, and the second slider and the rotating shaft have corresponding sliding grooves inside, with the same wedge block slidably connected in the two sliding grooves. A spring is connected between one end of the wedge block and the sliding groove of the rotating shaft. A wedge groove is opened at one end of the first slider near the second slider, and the other end of the wedge block extends out of the sliding groove of the second slider and is located in the wedge groove of the first slider. There is damping between the inclined surface of the wedge groove of the first slider and the inclined surface of the wedge block.

[0011] The beneficial effects of this utility model are:

[0012] 1. This utility model, through the setting of a heating plate and a heat-conducting rod, can melt the part of the spinning yarn that is in contact with the heat-conducting rod by heating, so that the spinning yarn and the heat-conducting rod are bonded together by the melted spinning yarn, thereby enabling the heat-conducting rod to collect the messy and disordered spinning yarn by rotating.

[0013] 2. This utility model, through the setting of the oblique hook and hook rod, can make the spinning yarn wrap around the oblique hook and hook rod by rotation, thereby stably pulling the spinning yarn. Then, through the cooperation of electric slide rail and electric slider, the spinning yarn is wound around the stretching shaft for stretching, avoiding the safety hazards caused by manual operation. Attached Figure Description

[0014] Figure 1 This is a schematic diagram of the overall structure of this utility model;

[0015] Figure 2 This is a schematic diagram of the structure of the electric slide rail of this utility model;

[0016] Figure 3 This is a schematic diagram of the heating plate and heat-conducting rod of this utility model;

[0017] Figure 4 This is a schematic diagram of the structure of the cutting blade of this utility model;

[0018] Figure 5 This is a schematic diagram of the rear part of the tensile plate of this utility model;

[0019] Figure 6 This is a schematic diagram of the structure of the second gear of this utility model;

[0020] Figure 7 This is a schematic diagram of the structure of the wedge block of this utility model;

[0021] Figure 8 This utility model Figure 2 Enlarged view of point A in the middle.

[0022] In the attached diagram, the following are the reference numerals: 1-stretching plate, 2-extrusion device, 3-immersion drive device, 4-stretching shaft, 5-spinning, 6-electric slide rail, 7-electric slider, 8-first slider, 9-second slider, 901-first slide groove, 10-rotating shaft, 11-first gear, 12-slanted hook, 13-hook rod, 14-first magnet, 15-second magnet, 16-first rack, 17-slide plate, 1701-second slide groove, 18-elastic plate, 19-cutting blade, 20-second rack, 21-second gear, 22-third rack, 23-sliding frame, 24-motor, 2401-moving shaft, 25-heating plate, 26-heat conducting rod, 27-push rod, 28-cylinder, 29-wedge block, 30-spring. Detailed Implementation

[0023] The embodiments of this utility model will now be described in detail with reference to the accompanying drawings.

[0024] An FDY spinning and stretching device, such as Figures 1-8As shown, the device includes a stretching plate 1, a pressing device 2 on top of the stretching plate 1, and an immersion driving device 3 at one end of the stretching plate 1. Both the pressing device 2 and the immersion driving device 3 are external devices and do not need to be connected to the stretching plate 1. The pressing device 2 can discharge the spinning yarn 5, and the immersion driving device 3 can clamp the spinning yarn 5 through its own clamping device and drive the spinning yarn 5 to the next immersion step. Several stretching shafts 4 are rotatably arranged on one side of the stretching plate 1. The rotation of the stretching shafts 4 can stretch the spinning yarn 5, and each stretching shaft 4 is electrically driven (since the stretching shafts 4 are existing technology, the power source driving the rotation of the stretching shafts 4 is not shown). The device also includes a hooking device and a debris removal device. The hooking device includes a second slider 9. A first sliding groove 901 is formed through the stretching plate 1. A second slider 9 is slidably connected inside the groove 901. A rotating shaft 10 is fixedly connected to one side of the second slider 9. A first gear 11 is rotatably connected to one end of the rotating shaft 10. A slanted hook 12 and a hook rod 13 for hooking the spinning yarn 5 are fixedly installed on the side of the first gear 11 away from the rotating shaft 10. The outer wall of the hook rod 13 is provided with damping. The impurity removal device includes a heating plate 25. A racetrack-shaped slide groove is opened through the stretching plate 1, and a movable shaft 2401 is movably connected inside the racetrack-shaped slide groove. A motor 24 is connected to one end of the movable shaft 2401, and the heating plate 25 is detachably snapped to the other end of the movable shaft 2401. Several heat-conducting rods 26 are fixedly connected to the end of the heating plate 25 away from the movable shaft 2401. The heating plate 25 can heat the heat-conducting rods 26. The heated temperature is only enough to slightly melt the spinning yarn 5, so that the melted part of the spinning yarn 5 has a certain degree of stickiness.

[0025] The hooking device also includes an electric slide rail 6. An electric slide rail 6 is provided on the stretching plate 1. The electric slide rail 6 is connected to the first slide groove 901. An electric slider 7 is slidably connected inside the electric slide rail 6. A first magnet 14 and a second magnet 15 are respectively fixed to one end of the second slider 9 opposite to the electric slider 7. The magnetic poles of the first magnet 14 and the second magnet 15 are opposite.

[0026] The hooking device also includes a cutting blade 19. A second slide groove 1701 is provided on one side of the stretching plate 1. A slide plate 17 is slidably connected in the second slide groove 1701. The length of the second slide groove 1701 is shorter than the length of the first slide groove 901. The cutting blade 19 is fixedly connected to the end of the slide plate 17 away from the stretching plate 1. An elastic plate 18 is fixedly connected to the top of the slide plate 17. The elastic plate 18 is in contact with the rotating shaft 10.

[0027] The hooking device also includes a first rack 16. The tension plate 1 is located on one side of the second slide groove 1701 and two first racks 16 are installed by two fixing plates. The first racks 16 are located above and below the two ends of the electric slide rail 6, respectively. The first racks 16 can mesh with the first gear 11.

[0028] The impurity removal device also includes a first slider 8, which is slidably connected to a first slide groove 901 and slidably contacts a second slider 9. A second rack 20 is fixedly connected to the side of the first slider 8 away from the second slider 9. The second rack 20 is located on the rear side of the stretching plate 1. A second gear 21, which is rotatably connected to the stretching plate 1, is meshed below the second rack 20. A third rack 22 is meshed below the second gear 21. A sliding frame 23, which is slidably connected to the stretching plate 1, is fixedly connected to the bottom of the third rack 22. The sliding frame 23 is fixedly connected to a motor 24. A push rod 27, which is slidably connected to the stretching plate 1, is fixedly connected to one side of the sliding frame 23. A cylinder 28, which is fixedly connected to the stretching plate 1, is fixedly connected to one side of the bottom of the push rod 27.

[0029] The impurity removal device also includes an elastic wedge block 29. The second slider 9 and the rotating shaft 10 have corresponding sliding grooves inside, and the same wedge block 29 is slidably connected in the two sliding grooves. A spring 30 is connected between one end of the wedge block 29 and the sliding groove of the rotating shaft 10. The first slider 8 has a wedge groove at one end near the second slider 9. The other end of the wedge block 29 extends out of the sliding groove of the second slider 9 and is located in the wedge groove of the first slider 8. There is damping between the inclined surface of the wedge groove of the first slider 8 and the inclined surface of the wedge block 29.

[0030] Working principle:

[0031] After the extrusion device 2 extrudes the polyester fiber into spun yarn 5, it is cooled and stored inside. Then, it is discharged to the stretching device for stretching. When the spun yarn 5 is first discharged from the extrusion device 2, one end is disordered, which does not meet the specifications required by the stretching device. Therefore, the device does not stretch the disordered end of the spun yarn 5; it falls directly onto the heat-conducting rod 26. At this time, the heating plate 25 is activated, heating the heat-conducting rod 26. The temperature of the heat-conducting rod 26 melts the spun yarn 5 in contact with it, allowing the heat-conducting rod 26 to adhere to the unmelted spun yarn 5. Then, the motor 24 is activated, driving the heating plate 25 and the heat-conducting rod 26 to rotate via the movable shaft 2401. Rotating rod 26 can wind up the disordered spun yarn 5. Since the spun yarn 5 is disordered, the heat-conducting rod 26 does not need to be neat when winding it up; it only needs to be able to wind the disordered spun yarn 5 onto the heat-conducting rod 26. The winding operation of the heat-conducting rod 26 will continue until the orderly part of the spun yarn 5 contacts the heat-conducting rod 26. At this time, cylinder 28 is activated. Cylinder 28 pushes sliding frame 23 to slide on stretching plate 1 through push rod 27. Sliding frame 23 will drive movable shaft 2401, heating plate 25 and heat-conducting rod 26 to slide synchronously through motor 24. At the same time, sliding frame 23 will also drive third rack 22 to slide synchronously. Third rack 22 meshes with second gear 21, and second gear 21 meshes with second rack 20. The sliding of third rack 22 will drive second rack 20 to slide in the opposite direction. Figure 5 Based on the direction, the third rack 22 slides to the left, and the second rack 20 slides to the right. If... Figure 1 or Figure 2Based on the direction, the second rack 20 slides to the left. The sliding of the second rack 20 will drive the first slider 8 to slide within the first groove 901. The first slider 8 pushes the wedge block 29 to move synchronously through the wedge groove on it. The wedge block 29 will drive the second slider 9 to slide synchronously. The second slider 9 will drive the rotating shaft 10, the first gear 11, the oblique hook 12, the hook rod 13, and the first magnet 14 to slide synchronously. The sliding of the rotating shaft 10 will drive the slide plate 17 to slide within the second groove 1701 through the elastic plate 18. The slide plate 17 will drive the cutting blade 19 to slide synchronously. The sliding of the cutting blade 19 will contact the spinning yarn 5 and cut it, so that the spinning yarn 5 is orderly. The ordered parts separate from the disordered parts. Then, the oblique hook 12 contacts the orderly part of the spinning filament 5. As the oblique hook 12 moves, the spinning filament 5 moves along the inclined surface of the oblique hook 12 away from the rotating shaft 10. The spinning filament 5 then passes over the oblique hook 12 and is positioned between the oblique hook 12 and the hook rod 13. During this process, the slide plate 17 has moved to one end of the second slide groove 1701. At this point, the slide plate 17 can no longer move, while the rotating shaft 10 continues to move. The movement of the rotating shaft 10 will compress the elastic plate 18, causing it to bend. Then, the rotating shaft 10 will pass over the elastic plate 18 and no longer contact it. The rotating shaft 10 continues... The first gear 11, which is rotatably connected to the first gear 16, will mesh with one of the first racks 16 and rotate 360° counterclockwise. The first gear 11 drives the oblique hook 12 and hook rod 13 to rotate synchronously. The rotation of the oblique hook 12 and hook rod 13 will hook the spinning thread 5 between them, so that the spinning thread 5 is wound around the oblique hook 12 and hook rod 13. Through the winding of the spinning thread 5 and the friction between the damping of the hook rod 13 and the spinning thread 5, the oblique hook 12 and hook rod 13 can continuously hook the spinning thread 5 and can stably pull the spinning thread 5. As the first slider 8, the second slider 9 and the rotating shaft 10 continue to move, the first slider 8 will move to one end of the first groove 901. At this time, The first slider 8 can no longer move. At the same time, the second slider 9 causes the first magnet 14 and the second magnet 15 to make magnetic contact. It is worth noting that at this time, the cylinder 28 can no longer extend. The third rack 22 and the sliding frame 23 also stop moving. The heating plate 25 and the heat-conducting rod 26 are located at the end of the racetrack-shaped slide groove on the stretching plate 1 away from the electric slide rail 6. At this time, the heating plate 25 can be turned off. After the heating plate 25 and the heat-conducting rod 26 have cooled down, the heating plate 25 can be disassembled on the movable shaft 2401. This allows the messy and disordered spinning fibers 5 on the heat-conducting rod 26 to be cleaned. After cleaning, the heating plate 25 can be snapped back onto the movable shaft 2401.

[0032] When the first magnet 14 and the second magnet 15 are in magnetic contact and the cylinder 28 no longer extends, the electric slider 7 is activated. The electric slider 7 will slide along the electric slide rail 6 and drive the second slider 9, the rotating shaft 10 and the spinning 5 to move synchronously through the first magnet 14 and the second magnet 15. Since the first slider 8 can no longer slide at this time, the inclined surface of the wedge groove of the first slider 8 will squeeze the wedge block 29, so that it is contained in the sliding groove of the second slider 9 and the rotating shaft 10. The spring 30 contracts. It is worth noting that in the subsequent process, the wedge block 29 will always be restricted by the electric slide rail 6. Before the wedge block 29 and the wedge groove of the first slider 8 are re-corresponded, the wedge block 29 will always be contained in the sliding groove of the second slider 9 and the rotating shaft 10.

[0033] When the electric slider 7 drives the second slider 9, the rotating shaft 10 and the spinning 5 to slide along the electric slide rail 6 via the first magnet 14 and the second magnet 15, the spinning 5 will be wound around several stretching shafts 4 until the electric slider 7 slides to the position of the electric slide rail 6 close to the soaking drive device 3. At this time, the first gear 11 will mesh with the first rack 16 at this position and rotate 360° clockwise, so that the oblique hook 12 and the hook rod 13 rotate synchronously and release the spinning 5. At this time, the spinning 5 is no longer wrapped around the oblique hook 12 and the hook rod 13. Then the soaking drive device 3 will clamp the spinning 5 through its own clamping device and drive the spinning 5 to the next step, that is, the soaking step.

[0034] After the stretching operation of spinning 5 is completed, the electric slider 7 is activated, causing it to slide back and reset along the electric slide rail 6. The electric slider 7 drives the second slider 9 and the rotating shaft 10 to reset until the electric slider 7 slides to one end of the electric slide rail 6 close to the first groove 901. At this point, the electric slider 7 stops sliding, and the wedge block 29 corresponds to the wedge groove of the first slider 8. The spring 30 extends elastically and drives the wedge block 29 to engage in the wedge groove of the first slider 8. Then, the control cylinder 28 retracts. The cylinder 28 drives the third rack 22 and the motor 24 to reset via the push rod 27 and the sliding frame 23. The motor 24 drives the heating plate 25 and the heat-conducting rod 26 to reset via the movable shaft 2401. The third rack 22, through the meshing relationship between the second rack 20, the second gear 21 and the third rack 22, drives the first slider 8 to reset. The first slider 8 passes through the wedge groove. The inclined surface pushes the wedge block 29 to slide synchronously. It should be noted that at this time, the first slider 8 drives the wedge block 29 to slide synchronously through the damping between the inclined surface of the wedge groove and the inclined surface of the wedge block 29. The wedge block 29 drives the second slider 9 and the rotating shaft 10 to slide and reset synchronously. The second slider 9 and the rotating shaft 10 drive the structure on them to reset synchronously. During the reset process, the rotating shaft 10 will contact the elastic plate 18 and push the elastic plate 18 to reset. The elastic plate 18 drives the slide plate 17 and the cutting blade 19 to reset. When the slide plate 17 slides to the end of the second slide groove 1701 away from the electric slide rail 6, the slide plate 17 and the elastic plate 18 have completed the reset and no longer slide. The rotating shaft 10 continues to slide and will squeeze and deform the elastic plate 18. Then the rotating shaft 10 passes over the elastic plate 18. At this time, the cylinder 28 has completed the retraction and the rotating shaft 10 no longer slides, thus completing the overall reset.

[0035] The above description is only a preferred embodiment of the present utility model. It should be noted that for those skilled in the art, several improvements and modifications can be made without departing from the principle of the present utility model, and these improvements and modifications should also be considered within the protection scope of the present utility model.

Claims

1. An FDY spinning and stretching device, comprising a stretching plate (1), an extrusion device (2) disposed above the stretching plate (1), an immersion drive device (3) disposed at one end of the stretching plate (1), and a plurality of stretching shafts (4) rotatably disposed on one side of the stretching plate (1), wherein spun yarn (5) can be discharged from the extrusion device (2), characterized in that, It also includes a hooking device and a debris removal device. The hooking device includes a second slider (9). A first groove (901) is provided through the stretching plate (1). The second slider (9) is slidably connected in the first groove (901). A rotating shaft (10) is fixedly connected to one side of the second slider (9). A first gear (11) is rotatably connected to one end of the rotating shaft (10). A slanted hook (12) and a hook rod (13) for hooking the spinning (5) are fixedly installed on the side of the first gear (11) away from the rotating shaft (10). The debris removal device includes a heating plate (25). A racetrack-shaped groove is provided through the stretching plate (1). A movable shaft (2401) is movably connected in the racetrack-shaped groove. A motor (24) is connected to one end of the movable shaft (2401). The heating plate (25) is detachably snapped to the other end of the movable shaft (2401). Several heat-conducting rods (26) are fixedly connected to the end of the heating plate (25) away from the movable shaft (2401).

2. The FDY spinning and stretching device according to claim 1, characterized in that: The hooking device also includes an electric slide rail (6), an electric slide rail (6) is provided on the stretching plate (1), an electric slider (7) is slidably connected inside the electric slide rail (6), and a first magnet (14) and a second magnet (15) are respectively fixed to one end of the second slider (9) opposite to the electric slider (7).

3. The FDY spinning and stretching device according to claim 2, characterized in that: The hooking device also includes a cutting blade (19), a second groove (1701) is provided on one side of the stretching plate (1), a sliding plate (17) is slidably connected in the second groove (1701), the cutting blade (19) is fixedly connected to one end of the sliding plate (17) away from the stretching plate (1), and an elastic plate (18) is fixedly connected to the top of the sliding plate (17), and the elastic plate (18) is in contact with the rotating shaft (10).

4. The FDY spinning and stretching device according to claim 3, characterized in that: The hooking device also includes a first rack (16). The tension plate (1) is located on one side of the second slide (1701) and two first racks (16) are installed by a fixing plate. The first racks (16) are located above and below the two ends of the electric slide rail (6).

5. The FDY spinning and stretching device according to claim 4, characterized in that: The impurity removal device also includes a first slider (8), a first slider (8) that is slidably connected in a first groove (901) and slidably in contact with a second slider (9), a second rack (20) fixedly connected to the side of the first slider (8) away from the second slider (9), a second gear (21) that is rotatably connected to the stretching plate (1) meshes below the second rack (20), a third rack (22) that is meshed below the second gear (21), a sliding frame (23) that is slidably connected to the stretching plate (1) is fixedly connected to the bottom of the third rack (22), a sliding frame (23) that is slidably connected to the stretching plate (1) is fixedly connected inside the sliding frame (23), a push rod (27) that is slidably connected to the stretching plate (1) is fixedly connected to one side of the sliding frame (23), and a cylinder (28) that is fixedly connected to the stretching plate (1) is fixedly connected to one side of the bottom of the push rod (27).

6. The FDY spinning and stretching device according to claim 5, characterized in that: The impurity removal device also includes an elastic wedge block (29), and the second slider (9) and the rotating shaft (10) are provided with corresponding sliding grooves. The same wedge block (29) is slidably connected in the two sliding grooves. A spring (30) is connected between one end of the wedge block (29) and the sliding groove of the rotating shaft (10). The first slider (8) is provided with a wedge groove at one end near the second slider (9). The other end of the wedge block (29) extends out of the sliding groove of the second slider (9) and is located in the wedge groove of the first slider (8). There is damping between the inclined surface of the wedge groove of the first slider (8) and the inclined surface of the wedge block (29).