CN214007745U

CN214007745U - Self-tightening anti-loose fastening device

Info

Publication number: CN214007745U
Application number: CN202020772754.XU
Authority: CN
Inventors: 李武彬
Original assignee: Jiangsu Hanzhijin Technology Co ltd
Current assignee: Jiangsu Hanzhijin Technology Co ltd
Priority date: 2020-05-11
Filing date: 2020-05-11
Publication date: 2021-08-20
Anticipated expiration: 2030-05-11

Abstract

The utility model discloses a locking fastener of self-clinching formula to improve the locking performance of device, reduce the manufacturing cost of product, be suitable for the needs of high standard high safety and complicated operating mode environment. The self-tightening bolt comprises a bolt 1 and a self-tightening nut, wherein the bolt 1 is provided with a common and standard external thread; the self-tightening nut consists of two sections of continuous deformed threads with self-tightening effect, the front section deformed thread a1 plays a fastening role, and the rear section deformed thread a2 plays a role in keeping the anti-loosening capacity increased; the self-tightening nut is matched and connected with the bolt to clamp the workpiece more and more tightly, or a certain pretightening force is provided at any position of the bolt. The technical scheme of the utility model reliable antidetonation locking performance can be brought, manufacturing cost, the reuse rate, the life of the improvement nut that are showing guarantee to receive under various adverse operating environment such as frequent vibration and load change each link screw thread pair not hard up, play the effect of real locking, application scope is extensive.

Description

Self-tightening anti-loose fastening device

Technical Field

The utility model relates to a locknut device belongs to locking fastening work piece technical field.

Background

In production life, the fastener is usually not separated in the connecting and assembling process, and the fastener brings convenience to the mechanical industry.

In the connection fitting, a bolt-nut connection is the most commonly used fastening structure. The machinery that adopts bolt and nut fastener is at the in-service use in-process, because the influence of complicated operating mode, the bolt and nut inevitably can drop by oneself in the environment of frequent vibration and alternating load to cause the use danger.

In order to solve the problem of loosening of the fastening device, scientists and engineers in many countries in the world make a lot of experimental researches, and the anti-loosening fastening device originates abroad, generally adopts methods such as locking plates, pins, nylon embedding, deformed threads, chemical glue coating and the like, delays the time for the self-loosening of the fastening device to a certain extent, but does not solve the problem fundamentally. The prior anti-loosening methods in China are many, wherein the anti-loosening method is not detachable, the detachable threaded connection is changed into the non-detachable threaded connection by adopting the modes of welding, bonding or punching riveting and the like, the anti-loosening method belongs to the more reliable traditional anti-loosening method, but the defects are obvious,

that is, the threaded fastener cannot be reused and the operation is very troublesome when mounting and dismounting. The other method is to adopt a mechanical fixing piece for loosening prevention, and the principle is to utilize the mechanical fixing piece to fix and pin between a threaded piece and a connected piece or between the threaded piece and the threaded piece so as to prevent loosening. The anti-loosening method has poor reliability, does not fundamentally solve the problems, has multiple potential safety hazards, and is difficult to adapt to the requirements of high standard, high safety and other complex environmental conditions.

Disclosure of Invention

The utility model aims at overcoming the not enough of prior art, providing the locking fastener of self-clinching formula, through improving nut thread portion structure, reach more outstanding reliable locking purpose.

The utility model discloses following technical scheme has specifically been adopted: the self-tightening anti-loose fastening device comprises a bolt and a nut; the nut is connected with the bolt through threads, the inner hole thread of the nut is composed of two sections of continuous deformation threads with the same pitch, the deformation structure and the deformation mode of the front section deformation threads and the rear section deformation threads are different, the pitch diameter of the front section deformation threads is larger than that of the rear section deformation threads, the front section deformation threads are provided with wedge angles, and the rear section deformation threads are provided with trapezoidal angles.

Furthermore, the front section of deformed thread is a thread-type angular deformed thread, a wedge-shaped inclined plane is arranged at the root of the thread, the angle (wedge angle) between the wedge-shaped inclined plane and the axis is smaller than the thread angle, and the pitch diameter of the section of internal thread is the same as that of the common thread; when the nut and the bolt are mutually screwed to compress a workpiece, the tooth point of the external thread of the bolt can tightly prop against the wedge-shaped inclined plane of the front section deformed thread, so that a larger locking force is generated. Because the angle of the tooth shape is changed, the normal force generated by the contact between the threads is increased, so the normal pressure of the front section deformed threads is far greater than the fastening pressure, and the generated anti-loosening friction force is also greatly increased. Meanwhile, when the external thread of the bolt is meshed with the deformed internal thread of the front section of the nut, the load is uniformly distributed on the full length of the contacted spiral line section by the wedge-shaped inclined surface, and more than 80% of total load is prevented from being intensively acted on thread surfaces of the first and second teeth when the common thread is meshed, so that the defect that the common standard coupling pair is easy to loosen in a vibration environment is overcome.

Furthermore, the rear section deformed thread is a tooth-shaped angular deformed thread, a trapezoidal angle is arranged at the tooth bottom of the rear section deformed thread, the angle between a trapezoidal tooth edge and a tooth-shaped central axis (trapezoidal tooth angle) is smaller than the original tooth angle, the pitch diameter of the section of internal thread is smaller than the pitch diameter value of the thread of the matched bolt, and the optimal value is 0.05mm-0.2 mm; when the nut and the bolt are screwed or the workpiece is pressed tightly, the two sides of the thread of the external thread of the bolt can be tightly attached to the two sides of the thread of the rear-section deformed thread, so that large friction force and locking force are generated.

Because the pitch diameter of the section of the thread is reduced, interference exists between the section of the thread and the external thread of the bolt, and the friction force and the anti-loosening locking force generated by the thread connecting surface are gradually increased along with the increase of the interference; then the pitch diameter diminishes and can make this section internal thread major diameter diminish (be less than the big footpath of connecting bolt external screw thread), can oppress the cusp of junction bolt external screw thread and make its deformation destroy even, and the space that the trapezoidal angular form of kerve design formed effectively avoids the destruction to bolt external screw thread cusp, and has increased the flexible space that interference magnitude arouses the deformation.

When the bolt thread is meshed with the rear section deformation thread of the nut, the section deformation thread coupling pair overcomes the defect that a common standard coupling pair is easy to loosen in a vibration environment, simultaneously has a protection effect on the external thread of the bolt, and prolongs the service life.

Further, nut anterior segment deformation screw portion is inequality with back end deformation screw portion peripheral shape, the utility model discloses be directional during well nut fastening, anterior segment deformation screw portion terminal surface and work piece contact change nut peripheral shape and can effectively distinguish.

The working principle of the utility model is that the normal force is increased by the wedge surface arranged on the front section of the two-section continuous deformation thread with the same pitch of the inner hole thread of the nut, thereby greatly improving the capability of the nut to resist shock and cause loosening during fastening; the interference magnitude of the trapezoidal angle arranged at the rear section and 0.05mm-0.2mm ensures that the nut forms frictional resistance generated by interference at any position of the bolt or when fastening a workpiece, and simultaneously the trapezoidal angle for preventing the damage to the external thread of the bolt is designed; when the friction anti-loosening locking force formed by the two sections of threads is mutually superposed and enhanced, good anti-loosening capability is inevitably formed.

By adopting the technical scheme, the utility model discloses can realize following technological effect: 1. reliable anti-seismic and anti-loosening performance: the utility model discloses can realize dual locking, warp the increase of screw thread wedge surface normal force through the nut anterior segment promptly and lock on the one hand, on the other hand nut back end warp the increase of magnitude of interference of screw thread and lock for reach dual auto-lock, from tighting when the nut realizes locking bolt, realized the locking performance of antidetonation better. 2. According to the utility model discloses a principle can know, the utility model discloses can lock the bolt under the condition of not destroying screw thread substructure, consequently can show the life who improves nut and bolt. 3. Can be repeatedly used: the design of the trapezoidal deformation angle of nut back end plays the outer tooth of protection bolt, provides the effect in space for warping, consequently the utility model discloses can realize used repeatedly. 4. Without any auxiliary locking elements such as spring washers, stop washers, etc. The fastening device can achieve the purpose of complete self-locking without any external auxiliary element. 5. The product cost can be greatly reduced, and the market occupation space is improved. 6. The utility model belongs to the fastener of the type of joining in marriage, the specification model adopts standard size, with standard external screw thread phase-match. 7. The utility model discloses do not receive the influence that the temperature acutely changed, but the wide application is on the spare part that requires self-locking function, like on high-speed railway, space flight, boats and ships, car etc. require high auto-lock part, set up the specification according to actual need can. 8. Any metal and nonmetal can be selected, and the material, the shape and the dimension are not limited. 9. Can realize the same locking force of screwing in and screwing out, and achieve the purpose of not loosening the nut

Drawings

Fig. 1 is a structure diagram of the device of the present invention.

Fig. 2 is a schematic view of the thread pair structure of the present invention.

Fig. 3 is a schematic view of the front section deformed thread of the present invention.

Fig. 4 is a schematic diagram of the rear deformed thread of the present invention.

Fig. 5 is a schematic view of an embodiment of the present invention.

Fig. 6 is a schematic view of an embodiment of the present invention.

Symbolic illustration in the drawings: 1, a bolt; 2, a nut; 3, a gasket; a1 front segment deformed thread; a2 rear segment deformed thread; a3 bolt threads; c1 wedge angle; c2 trapezoid angle; s is a wedge surface; c, tooth corners; b, axial line of the nut; v, original tooth angle; d, pitch diameter of bolt threads; d1 front section deformed thread pitch diameter; d2 back deformed thread pitch diameter; e a normal pressure increasing portion; k trapezoidal flexible space.

Detailed Description

To facilitate the understanding and practice of the present invention for those skilled in the art, the following detailed description of the present invention is provided in connection with the accompanying drawings and the detailed description.

As shown in fig. 1, 2, 3 and 4, the device is a self-tightening anti-loose fastening device, which comprises a bolt 1 and a nut 2; the nut is connected with the bolt through threads, the inner hole thread of the nut consists of two sections of continuous deformation threads with the same pitch, the deformation structures and the deformation modes of the front section deformation thread a1 and the rear section deformation thread a2 are different, the intermediate diameter d1 of the front section deformation thread a1 is larger than the intermediate diameter d2 of the rear section deformation thread a2, the front section deformation thread a1 is provided with a wedge angle c1, and the rear section deformation thread a2 is provided with a trapezoidal angle c 2.

Example 1: as shown in fig. 1, 5 and 6, the screw thread a3 of the bolt is a standard screw thread of 60 degrees, and the front section of the nut is a common internal screw thread of 60 degrees, and the pitch diameter of the common internal screw thread is the same as that of the common screw thread; the angle (wedge angle) of the wedge-shaped inclined plane to the axis is 48 degrees in the front-section deformed thread a 1; when the nut 2 and the bolt 1 are mutually screwed to press a workpiece, the tooth tips of the external threads of the bolt can tightly abut against the wedge-shaped inclined plane S of the front section deformed thread a1 to form a normal pressure increasing part E, so that the normal force generated by the contact between the threads is increased, the normal pressure of the front section deformed thread a1 is far greater than the fastening pressure, and the generated anti-loosening friction force is greatly increased; meanwhile, when the external thread of the bolt is meshed with the internal thread of the nut 2, the wedge-shaped inclined surface S enables the load to be uniformly distributed on the full length of the section of the contacted spiral line, and the phenomenon that more than 80% of total load is concentrated on thread surfaces of the first and second teeth when the common thread is meshed is avoided, so that the defect that the common standard coupling pair is easy to loosen in a vibration environment is overcome.

The rear section deformed thread a2 is a 60-degree deformed thread, the pitch diameter of the thread is less than the pitch diameter value of the thread of the matched bolt by 0.1mm, and a 15-degree trapezoidal thread angle is arranged at the root of the thread; when the nut and the bolt are screwed at any position or tightly press a workpiece, interference exists between the nut and the bolt and the external thread of the bolt, two side surfaces of the thread form of the 60-degree thread section of the deformed thread can be tightly attached to the two side surfaces of the thread form of the 60-degree thread of the bolt, and the friction force and the anti-loosening locking force generated along with the increase of the interference are gradually increased; then the pitch diameter diminishes and can make this section internal thread major diameter diminish (be less than the big footpath of connecting bolt external screw thread), can oppress the cusp of junction bolt external screw thread and make its deformation destroy even, and the space that the 15 trapezoidal angles of root design formed can effectively avoid the destruction to bolt external screw thread cusp, and can increase the elastic expansion space K that magnitude of interference arouses the deformation.

Two sections of continuous deformed threads with the same pitch are arranged in the inner hole thread of the nut 2, and a 48-degree wedge-shaped surface S is arranged at the front section of the deformed threads, so that the normal force is increased, and the looseness resistance of the nut caused by vibration resistance during fastening is greatly improved; the rear section is provided with a 15-degree trapezoidal angle and a magnitude of interference of 0.1mm, so that the nut forms frictional resistance caused by interference at any position of the bolt or when a workpiece is fastened, and meanwhile, the trapezoidal angle for preventing the damage to the external thread of the bolt is designed; when the friction anti-loosening locking force formed by the two sections of threads is mutually superposed and enhanced, good anti-loosening capability is inevitably formed.

The foregoing is only a preferred embodiment of the present invention, and it should be noted that, for those skilled in the art, a plurality of improvements and decorations can be made without departing from the concept of the present invention, and these improvements and decorations should also be considered as the protection scope of the present invention.

Claims

1. From locking fastener of compact form, including bolt (1), nut (2), the nut passes through cooperation threaded connection, its characterized in that with the bolt: the nut inner hole thread is composed of two sections of continuous deformation threads with the same pitch, the deformation structures and the deformation modes of the front section deformation thread (a 1) and the rear section deformation thread (a2) are different, the pitch diameter of the front section deformation thread (a 1) is larger than that of the rear section deformation thread (a2), the front section deformation thread (a 1) is provided with a wedge angle (c1), and the rear section deformation thread (a2) is provided with a trapezoidal angle (c 2).

2. The self-clinching anti-loose fastener of claim 1, wherein: the front section deformed thread (a 1) is a thread type angle deformed thread, and a wedge-shaped inclined plane is arranged at the root of the thread.

3. The self-clinching anti-loose fastener of claim 2, wherein: the angle between the wedge-shaped inclined plane and the axis is smaller than the tooth corner (c).

4. The self-clinching anti-loose fastener of claim 1, wherein: the rear section deformed thread (a2) is a thread-shaped angular deformed thread, and a trapezoidal tooth surface (S) is arranged at the bottom of the thread.

5. The self-clinching anti-loose fastener of claim 4, wherein: the angle between the trapezoidal tooth edge and the tooth-shaped central axis is smaller than the original tooth angle (V).

6. The self-clinching anti-loose fastener of claim 1, wherein: the pitch diameter of the front section deformed thread (a 1) is the same as that of a common thread; the pitch diameter of the rear-section deformed thread (a2) is smaller than the pitch diameter value of the matched bolt thread (a3) by 0.05mm-0.2 mm.

7. The self-clinching anti-loose fastener of claim 1, wherein: the outer peripheral shapes of the front section deformed screw thread (a 1) and the rear section deformed screw thread (a2) are different.