CN111473093A

CN111473093A - Bolt

Info

Publication number: CN111473093A
Application number: CN202010488144.1A
Authority: CN
Inventors: 钱理
Original assignee: Suzhou Zhiyu Photoelectric Technology Co ltd
Current assignee: Suzhou Zhiyu Photoelectric Technology Co ltd
Priority date: 2020-06-02
Filing date: 2020-06-02
Publication date: 2020-07-31
Anticipated expiration: 2040-06-02
Also published as: CN111473093B

Abstract

The invention belongs to the technical field of bolts, and particularly relates to a bolt which comprises a pull rod and an adjusting shell, wherein after a pull rope for fixing goods is tensioned, a gear adjusting plate is moved, one end of a clamping strip is clamped in a corresponding annular ratchet on a ratchet wheel to be clamped, the adjusting swing plate is moved at the moment, the adjusting swing plate drives an adjusting ring to rotate, the adjusting ring drives the ratchet wheel to rotate through the clamping strip, the ratchet wheel drives an adjusting sleeve to rotate, the adjusting sleeve rotates to drive two first nuts to rotate through the matching of a guide block and a guide groove, the two first nuts slide towards one side provided with a locking spring while rotating, and the locking spring is compressed; generating pretightening force through a compressed locking spring; the problem that in operation, goods can shift because of vibration appearing in the road surface and make the stay cord relax, and the relaxation of stay cord arouses the screw-thread fit position of turn buckle both sides to lose the pretightning force for turn buckle easily breaks away from with the pull rod, causes the loss that can not retrieve.

Description

Bolt

Technical Field

The invention belongs to the technical field of bolts, and particularly relates to a bolt.

Background

The turnbuckle consists of an adjusting rod with left and right-handed threads, a nut and a pull rod; the lead screw is used for stretching, so that the tightness of the steel wire rope can be adjusted. The components may be tied up in component transport and loosened in installation correction.

However, the following problems may occur in the use of the turn buckle:

1. the stay cord that will fix the goods in the work is taut, but in operation, the goods can shift because of the road surface vibration appears and make the stay cord lax, and lax of stay cord arouses the screw-thread fit position of turn buckle both sides to lose the pretightning force for turn buckle and pull rod easily break away from, cause the loss that can not retrieve.

2. The threads of the turn-buckle are prone to failure under high tension, particularly failure at the thread-fit location.

It is necessary to design a self-pretightening turn buckle which improves the thread stress.

The invention designs a bolt to solve the problems.

Disclosure of Invention

In order to solve the defects in the prior art, the invention discloses a bolt which is realized by adopting the following technical scheme.

The utility model provides a bolt, it includes the pull rod, adjusts the shell, wherein adjusts the both ends fixed mounting of shell have two screw threads to opposite second nut soon, and the one end of pull rod has the drag hook, has the external screw thread on the excircle face of the pull rod other end, and the one end that two pull rods have the external screw thread is installed at the both ends of adjusting the shell through interior external screw thread fit, its characterized in that: an adjusting sleeve is rotatably arranged on the inner side of the adjusting shell; two first nuts with opposite thread turning directions are symmetrically and slidably mounted on the inner sides of the two ends of the adjusting sleeve; the two first nuts correspond to the two pull rods one by one and are matched with each other through internal and external threads respectively; a locking spring is respectively arranged between the two first nuts and the two inner end surfaces of the adjusting shell; and the adjusting shell is provided with a locking adjusting mechanism for controlling the two locking springs to press the two first nuts.

The locking adjusting mechanism comprises a ratchet wheel, an adjusting ring and a clamping strip, wherein two rows of annular ratchets distributed in parallel are arranged on the outer circular surface of the ratchet wheel, and the ratchet wheel is fixedly arranged on the adjusting sleeve; the adjusting ring is rotatably arranged on the inner circular surface of the adjusting shell and is in rotating fit with the ratchet wheel; the arc-shaped clamping strip is arranged on the adjusting ring in a swinging mode, and two ends of the clamping strip are respectively in one-way driving fit with the two rows of ratchets on the ratchet wheel in a one-to-one correspondence mode.

As a further improvement of the technology, two adjusting bulges are circumferentially and uniformly arranged on the outer circular surface of the adjusting shell.

As a further improvement of the technology, the outer circular surfaces of the two ends of the adjusting sleeve are provided with two symmetrically distributed annular grooves; two fixed supports are fixedly arranged on the inner circular surface of the adjusting shell, and the adjusting sleeve is arranged in the adjusting shell through the rotary matching of the two annular grooves and the two fixed supports.

As a further improvement of the technology, one end of the two locking springs connected with the inner end face of the adjusting shell is arranged on the inner end face of the adjusting shell through a thrust bearing.

As a further improvement of the present technology, the locking spring is a compression spring.

As a further improvement of the technology, two sliding grooves are respectively and uniformly arranged on the inner circular surfaces at the two ends of the adjusting sleeve in the circumferential direction; two sliding blocks are uniformly arranged on the outer circular surfaces of one ends of the two first nuts in the circumferential direction respectively; the two first nuts are slidably arranged at the two ends of the adjusting sleeve through the matching of the two sliding blocks and the sliding groove on the two first nuts; and one end of each of the two first nuts, which is not provided with the guide block, is fixedly provided with a limiting disc.

As a further improvement of the technology, an arc-shaped notch is formed in the outer circular surface of the adjusting shell, one end of the adjusting swing plate is fixedly mounted on the outer circular surface of the adjusting ring, and the other end of the adjusting swing plate penetrates through the arc-shaped notch to be in sliding fit with the arc-shaped notch.

As a further improvement of the technology, the clamping strip is arranged on the adjusting ring in a swinging mode through the supporting rotating shaft; a gear adjusting arc plate is fixedly arranged on the outer arc surface of the clamping strip, a first clamping groove is formed in the middle of the inner arc surface of the gear adjusting arc plate, and second clamping grooves which are symmetrically distributed are formed in two sides of the first clamping groove; the gear adjusting plate is arranged on the adjusting ring in a swinging mode through the supporting shaft, one end of the gear adjusting plate penetrates out of the arc-shaped notch and is located on the outer side of the adjusting shell, and the other end of the gear adjusting plate is matched with the first clamping groove and the second clamping groove.

The shortest distance between the axis of the first clamping groove and the axis of the support shaft is larger than the shortest distance between the axis of the second clamping groove and the axis of the support shaft.

As a further improvement of the technology, one end of the gear adjusting plate, which is matched with the first clamping groove and the second clamping groove, has elasticity; the gear adjusting arc plate has elasticity.

As a further improvement of the technology, the gear adjusting arc plate is made of rubber materials.

Compared with the traditional bolt technology, the bolt has the following beneficial effects:

1. according to the invention, after a pull rope for fixing goods is tensioned, a gear adjusting plate is moved, one end of a clamping strip is clamped in a corresponding annular ratchet on a ratchet wheel and is clamped, at the moment, an adjusting swing plate is moved, the adjusting swing plate drives an adjusting ring to rotate, the adjusting ring drives the ratchet wheel to rotate through the clamping strip, the ratchet wheel drives an adjusting sleeve to rotate, the adjusting sleeve rotates to drive two first nuts to rotate through the matching of a guide block and a guide groove, so that the two first nuts can slide towards one side provided with a locking spring while rotating, and the locking spring is compressed; generating pretightening force through a compressed locking spring; the problem that in operation, goods can shift because of vibration appearing in the road surface and make the stay cord relax, and the relaxation of stay cord arouses the screw-thread fit position of turn buckle both sides to lose the pretightning force for turn buckle easily breaks away from with the pull rod, causes the loss that can not retrieve.

2. In the invention, after the locking spring is compressed, the force of the two pull rods on the two first nuts can be transmitted to the adjusting shell through the locking spring; therefore, in this state, the pulling force of the two pull rods to the pull ropes on the two sides can be transmitted to the adjusting shell through the combined action of the two first nuts and the two second nuts at the two ends; the effect of design like this reduces the holding capacity of single nut, reduces the nut because of the great risk of damaging of pulling force.

3. When the locking spring is adjusted, the adjusting swing plate can be repeatedly moved, and the matching direction is one-way transmission after the clamping strip and the ratchet wheel are matched, so that the adjusting swing plate cannot drive the ratchet wheel to reversely rotate through the adjusting ring when being reset and moved, namely the adjustment of the locking spring cannot be influenced.

Drawings

Fig. 1 is an external view of an entire part.

Fig. 2 is a schematic view of the overall component distribution.

Fig. 3 is a schematic view of the installation of the locking adjustment mechanism.

Fig. 4 is a schematic view of the structure of the regulating shell.

Fig. 5 is a schematic view of the structure of the adjusting sleeve.

FIG. 6 is a ratchet mounting schematic.

Fig. 7 is a schematic view of a first nut structure.

Fig. 8 is a schematic view of the locking adjustment mechanism.

FIG. 9 is a schematic view of the adjustment swing plate and gear adjustment plate installation.

FIG. 10 is a schematic view of a strip installation.

Number designation in the figures: 1. a pull rod; 2. an adjustment housing; 3. locking the adjusting mechanism; 4. a first nut; 5. an adjusting sleeve; 6. an adjusting projection; 7. an arc-shaped notch; 8. a second nut; 9. a chute; 10. an annular groove; 11. fixing and supporting; 12. a ratchet wheel; 13. a limiting disc; 14. a thrust bearing; 15. a locking spring; 16. an adjusting ring; 17. adjusting the swing plate; 18. a gear adjusting plate; 19. clamping the strip; 20. a gear adjusting arc plate; 21. a first card slot; 22. a second card slot; 23. a support shaft; 24. a swing shaft; 25. a slide block.

Detailed Description

The following detailed description of embodiments of the present invention is provided in connection with the accompanying drawings and examples. The following examples or figures are illustrative of the present invention and are not intended to limit the scope of the present invention.

As shown in fig. 1 and 2, it includes a pull rod 1 and an adjusting shell 2, wherein as shown in fig. 4, two second nuts 8 with opposite thread turning directions are fixedly installed at two ends of the adjusting shell 2, as shown in fig. 1, 2 and 3, one end of the pull rod 1 has a draw hook, an external thread is provided on the external circular surface of the other end of the pull rod 1, as shown in fig. 1 and 2, one end of the two pull rods 1 with the external thread is installed at two ends of the adjusting shell 2 through the matching of the internal thread and the external thread, which is characterized in that: as shown in fig. 3 and 5, an adjusting sleeve 5 is rotatably mounted on the inner side of the adjusting shell 2; as shown in fig. 3, two first nuts 4 with opposite thread directions are symmetrically and slidably mounted on the inner sides of the two ends of the adjusting sleeve 5; the two first nuts 4 correspond to the two pull rods 1 one by one and are matched with each other through internal and external threads respectively; a locking spring 15 is respectively arranged between the two first nuts 4 and the two inner end surfaces of the adjusting shell 2; and the adjusting shell 2 is provided with a locking adjusting mechanism 3 for controlling the pressing force of the two locking springs 15 on the two first nuts 4. When the adjusting shell 2 is rotated, the two pull rods 1 are driven to approach to the middle, the two pull rods 1 approach to the middle to drive the two first nuts 4 to approach to the middle, however, the limiting discs 13 arranged on the two first nuts 4 are limited by the two ends of the adjusting sleeve 5, the adjusting sleeve 5 is rotatably arranged in the adjusting shell 2, the adjusting sleeve 5 can only rotate and cannot move transversely, so that the two first nuts 4 are limited by the adjusting sleeve 5 and cannot approach to the middle in the state, but the two pull rods 1 approach to the middle, so that the two first nuts 4 can rotate relative to the screw rod at the moment, and the transverse movement of the two pull rods 1 is adapted through rotation; the two first nuts 4 rotate to drive the adjusting sleeve 5 to rotate through the matching of the guide block and the guide groove; therefore, when the adjusting shell 2 and the adjusting sleeve 5 are rotated during normal use for fixing goods, the adjusting shell is a common turn buckle.

As shown in fig. 8 and 9, the locking adjustment mechanism 3 includes a ratchet 12, an adjustment ring 16, and a clamping strip 19, wherein as shown in fig. 6, two rows of annular ratchets are arranged in parallel on the outer circumferential surface of the ratchet 12, and the ratchet 12 is fixedly mounted on the adjustment sleeve 5; as shown in fig. 8 and 9, the adjusting ring 16 is rotatably mounted on the inner circumferential surface of the adjusting housing 2, and the adjusting ring 16 is rotatably engaged with the ratchet 12; as shown in fig. 9, the arc-shaped clip strip 19 is installed on the adjusting ring 16 in a swinging manner, and two ends of the clip strip 19 are respectively in one-to-one corresponding one-way driving fit with two rows of ratchet teeth on the ratchet 12.

As shown in fig. 4, two adjusting protrusions 6 are uniformly arranged on the outer circumferential surface of the adjusting shell 2 in the circumferential direction. The two adjustment projections 6 are designed to facilitate the operation of the user.

As shown in fig. 5, the outer circular surfaces of the two ends of the adjusting sleeve 5 are provided with two symmetrically distributed annular grooves 10; as shown in fig. 2 and 3, two fixed supports 11 are fixedly installed on the inner circumferential surface of the adjusting housing 2, and as shown in fig. 6, the adjusting sleeve 5 is installed in the adjusting housing 2 through the rotation fit of two annular grooves 10 and two fixed supports 11. The adjusting sleeve 5 is rotatable relative to the adjusting housing 2.

As shown in fig. 2 and 3, one end of the two locking springs 15 connected to the inner end surface of the adjusting case 2 is mounted on the inner end surface of the adjusting case 2 through a thrust bearing 14.

The lock spring 15 is a compression spring.

As shown in fig. 5, two sliding grooves 9 are uniformly formed on the inner circular surfaces of the two ends of the adjusting sleeve 5 in the circumferential direction; as shown in fig. 7, two sliding blocks 25 are respectively and uniformly installed on the outer circular surfaces of one ends of the two first nuts 4 in the circumferential direction; as shown in fig. 3, two first nuts 4 are slidably mounted at two ends of the adjusting sleeve 5 through the cooperation of two sliding blocks 25 thereon and the sliding groove 9; and a limiting disc 13 is fixedly arranged at one end of the two first nuts 4, which is not provided with the guide block. The first nut 4 and the adjusting sleeve 5 are guided and limited by the matching of the guide block and the guide groove; spacing dish 13 through the design plays limiting displacement to first nut 4, guarantees that locking spring 15 is in compression state all the time, and simultaneously when normally taut goods, it is spacing to first nut 4 through spacing dish 13 and the cooperation of adjusting collar 5, makes it rotate along with adjusting shell 2 together.

As shown in fig. 4, an arc notch 7 is formed on the outer circumferential surface of the adjusting shell 2, as shown in fig. 3, one end of the adjusting swing plate 17 is fixedly mounted on the outer circumferential surface of the adjusting ring 16, and the other end of the adjusting swing plate 17 penetrates through the arc notch 7 and is in sliding fit with the arc notch 7.

As shown in fig. 9 and 10, the clip strip 19 is mounted on the adjusting ring 16 by a support shaft 23; a gear adjusting arc plate 20 is fixedly installed on the outer arc surface of the clamping strip 19, a first clamping groove 21 is formed in the middle of the inner arc surface of the gear adjusting arc plate 20, and second clamping grooves 22 which are symmetrically distributed are formed in two sides of the first clamping groove 21; a gear adjusting plate 18 is mounted on the adjusting ring 16 through a support shaft in a swinging manner, one end of the gear adjusting plate 18 penetrates through the arc-shaped notch 7 and is located on the outer side of the adjusting shell 2, and the other end of the gear adjusting plate 18 is matched with a first clamping groove 21 and a second clamping groove 22.

The shortest distance between the axis of the first card slot 21 and the axis of the support shaft is greater than the shortest distance between the axis of the second card slot 22 and the axis of the support shaft.

One end of the gear adjusting plate 18, which is matched with the first clamping groove 21 and the second clamping groove 22, has elasticity; the gear adjusting arc plate 20 has elasticity.

The gear adjusting arc plate 20 is made of rubber material.

In the invention, when the goods are normally tensioned, the adjusting shell 2 is rotated, because one end of the adjusting swing plate 17 is matched with the starting end of the arc-shaped notch 7 in an initial state, and the rotating direction of the adjusting shell 2 is the same as the direction from the starting end to the tail end of the arc-shaped notch 7, when the adjusting shell 2 is rotated, the adjusting swing plate 17 is driven by the adjusting shell 2 to rotate together, the adjusting swing plate 17 drives the adjusting ring 16 to rotate together, so that the clamping strip 19 and the ratchet wheel 12 are in a separation state, and the adjusting sleeve 5 rotates to drive the ratchet wheel 12 to rotate, and the adjusting shell 2 drives the clamping strip 19 to rotate through the adjusting ring 16, so that the rotation interference can not be generated.

In the invention, after a pull rope for fixing goods is tensioned, the gear adjusting plate 18 is moved, the gear adjusting plate 18 swings towards the direction of the initial end of the arc-shaped notch 7, the gear adjusting plate 18 swings to enable one end of the gear adjusting plate, which is matched with the first clamping groove 21 on the gear adjusting arc plate 20, to swing in one second clamping groove 22, the gear adjusting plate 18 extrudes the gear adjusting arc plate 20 in the swinging process, the gear adjusting arc plate 20 swings to drive the clamping strip 19 to swing, so that one end of the clamping strip 19 is clamped in the corresponding annular ratchet on the ratchet wheel 12, at the moment, the adjusting swing plate 17 is moved, the adjusting swing plate 17 drives the adjusting ring 16 to rotate, the adjusting ring 16 drives the ratchet wheel 12 to rotate through the clamping strip 19, the ratchet wheel 12 drives the adjusting sleeve 5 to rotate, the adjusting sleeve 5 drives the two first nuts 4 to rotate through the matching of the guide block and the guide groove, and because the pull rods 1 at, then the two first nuts 4 will slide towards the side where the locking spring 15 is installed while rotating, and the locking spring 15 is compressed; generating a pre-tightening force through the compressed locking spring 15; the phenomenon that in operation, goods can shift because of vibration on the road surface to enable the pull rope to be loose is prevented, and the loosening of the pull rope causes the thread matching parts on the two sides of the turn buckle to lose pretightening force, so that the turn buckle is easily separated from the pull rod 1, and irreparable loss is caused.

After the locking spring 15 is compressed, the force of the two pull rods 1 on the two first nuts 4 is transmitted to the adjusting shell 2 through the locking spring 15; therefore, in this state, the pulling force of the two pull rods 1 to the pull ropes on the two sides can be transmitted to the adjusting shell 2 through the combined action of the two first nuts 4 and the two second nuts 8 on the two ends; the effect of design like this reduces the holding capacity of single nut, reduces the nut because of the great risk of damaging of pulling force.

In the invention, when the locking spring 15 is adjusted, the adjusting swing plate 17 can be repeatedly moved, and the clamping strip 19 and the ratchet wheel 12 are matched and driven in a single direction, so that the adjusting swing plate 17 cannot drive the ratchet wheel 12 to rotate reversely through the adjusting ring 16 when being reset and moved, namely, the adjustment of the locking spring 15 cannot be influenced.

The specific working process is as follows: when the bolt designed by the invention is used, in normal use, the adjusting shell 2 is rotated, the adjusting shell 2 drives the second nuts 8 at two ends to rotate, and because the two pull rods 1 with external threads at two ends are fixed with goods through the pull ropes, the second nuts 8 at two ends rotate to drive the pull rods 1 at two ends to approach to the middle, the pull ropes connected with the pull rods are tensioned, and then the goods are fixed; then, the gear adjusting plate 18 is moved, so that the gear adjusting plate 18 swings towards the starting end of the arc notch 7, the gear adjusting plate 18 swings to enable one end of the second clamping groove 22, which is matched with the first clamping groove 21 on the gear adjusting arc plate 20, to swing, the gear adjusting plate 18 presses the gear adjusting arc plate 20 in the swinging, the gear adjusting arc plate 20 swings to drive the clamping strip 19 to swing, so that one end of the clamping strip 19 is clamped in the corresponding annular ratchet on the ratchet wheel 12, at the moment, the adjusting swing plate 17 is moved, the adjusting swing plate 17 drives the adjusting ring 16 to rotate, the adjusting ring 16 drives the ratchet wheel 12 to rotate through the clamping strip 19, the ratchet wheel 12 drives the adjusting sleeve 5 to rotate, the adjusting sleeve 5 drives the two first nuts 4 to rotate through the matching of the guide block and the guide groove, and because the pull rods 1 at the two ends are already in a tensioned state, at the moment, the two first nuts 4 slide towards one side provided with the locking spring 15 while rotating, the locking spring 15 is compressed; generating a pre-tightening force through the compressed locking spring 15; the phenomenon that in operation, goods can shift because of vibration on the road surface to enable the pull rope to be loose is prevented, and the loosening of the pull rope causes the thread matching parts on the two sides of the turn buckle to lose pretightening force, so that the turn buckle is easily separated from the pull rod 1, and irreparable loss is caused.

When loosening, firstly, the gear adjusting plate 18 is moved to enable the gear adjusting plate 18 to swing towards the tail end direction of the arc-shaped notch 7, the gear adjusting plate 18 swings to enable one end of the gear adjusting plate, which is matched with the first clamping groove 21 on the gear adjusting arc plate 20, to swing to another second clamping groove 22, the gear adjusting plate 18 presses the gear adjusting arc plate 20 in the swinging process, the gear adjusting arc plate 20 swings to drive the clamping strip 19 to swing, one end of the clamping strip 19 is clamped in the corresponding annular ratchet on the ratchet wheel 12, at the moment, the adjusting swing plate 17 is moved to enable the adjusting swing plate 17 to drive the adjusting ring 16 to rotate, the adjusting ring 16 drives the ratchet wheel 12 to rotate through the clamping strip 19, the ratchet wheel 12 drives the adjusting sleeve 5 to rotate, the adjusting sleeve 5 drives the two first nuts 4 to rotate through the matching of the guide block and the guide groove, and because the pull rods 1 at two ends are in a tensioned state, at the moment, the two first nuts 4 slide towards one side far away from the locking, make locking spring 15 reset, after spacing dish 13 on two first nuts 4 and the both ends contact of adjusting collar 5 are spacing, the contra-rotation adjusting shell 2, adjusting shell 2 drives the second nut 8 rotation at both ends, and then loosens the stay cord of fixed goods.

Claims

1. The utility model provides a bolt, it includes the pull rod, adjusts the shell, wherein adjusts the both ends fixed mounting of shell have two screw threads to opposite second nut soon, and the one end of pull rod has the drag hook, has the external screw thread on the excircle face of the pull rod other end, and the one end that two pull rods have the external screw thread is installed at the both ends of adjusting the shell through interior external screw thread fit, its characterized in that: an adjusting sleeve is rotatably arranged on the inner side of the adjusting shell; two first nuts with opposite thread turning directions are symmetrically and slidably mounted on the inner sides of the two ends of the adjusting sleeve; the two first nuts correspond to the two pull rods one by one and are matched with each other through internal and external threads respectively; a locking spring is respectively arranged between the two first nuts and the two inner end surfaces of the adjusting shell; the adjusting shell is provided with a locking adjusting mechanism for controlling the pressing force of the two locking springs on the two first nuts;

2. A bolt according to claim 1, wherein: two adjusting bulges are uniformly arranged on the outer circular surface of the adjusting shell in the circumferential direction.

3. A bolt according to claim 1, wherein: two symmetrically distributed annular grooves are formed in the outer circular surfaces of the two ends of the adjusting sleeve; two fixed supports are fixedly arranged on the inner circular surface of the adjusting shell, and the adjusting sleeve is arranged in the adjusting shell through the rotary matching of the two annular grooves and the two fixed supports.

4. A bolt according to claim 1, wherein: and one end of each locking spring, which is connected with the inner end face of the adjusting shell, is arranged on the inner end face of the adjusting shell through a thrust bearing.

5. A bolt according to claim 1, wherein: the locking spring is a compression spring.

6. A bolt according to claim 1, wherein: two sliding grooves are uniformly formed in the circumferential direction on the inner circular surfaces at the two ends of the adjusting sleeve respectively; two sliding blocks are uniformly arranged on the outer circular surfaces of one ends of the two first nuts in the circumferential direction respectively; the two first nuts are slidably arranged at the two ends of the adjusting sleeve through the matching of the two sliding blocks and the sliding groove on the two first nuts; and one end of each of the two first nuts, which is not provided with the guide block, is fixedly provided with a limiting disc.

7. A bolt according to claim 1, wherein: the outer disc of adjusting the shell is opened has the arc breach, adjusts the one end fixed mounting of pendulum board on the outer disc of adjustable ring, adjusts the other end of pendulum board and wears out arc breach and arc breach sliding fit.

8. A bolt according to claim 7, wherein: the clamping strip is arranged on the adjusting ring in a swinging mode through the supporting rotating shaft; a gear adjusting arc plate is fixedly arranged on the outer arc surface of the clamping strip, a first clamping groove is formed in the middle of the inner arc surface of the gear adjusting arc plate, and second clamping grooves which are symmetrically distributed are formed in two sides of the first clamping groove; the gear adjusting plate is arranged on the adjusting ring in a swinging mode through the supporting shaft, one end of the gear adjusting plate penetrates through the arc-shaped notch and is located on the outer side of the adjusting shell, and the other end of the gear adjusting plate is matched with the first clamping groove and the second clamping groove;

the shortest distance between the axis of the first clamping groove and the axis of the supporting shaft is larger than the shortest distance between the axis of the second clamping groove and the axis of the supporting shaft.

9. A bolt according to claim 1, wherein: one end of the gear adjusting plate, which is matched with the first clamping groove and the second clamping groove, has elasticity; the gear adjusting arc plate has elasticity.

10. A bolt according to claim 9, wherein: the gear adjusting arc plate is made of rubber materials.