CN116517940A

CN116517940A - Pretightening force locknut

Info

Publication number: CN116517940A
Application number: CN202310553601.4A
Authority: CN
Inventors: 李黄薇; 李武彬; 费玉红
Original assignee: Individual
Current assignee: Individual
Priority date: 2023-05-17
Filing date: 2023-05-17
Publication date: 2023-08-01

Abstract

The invention belongs to the field of thread looseness prevention, and relates to a pretightening force locknut. The locknut thread comprises two continuous sections of internal threads, the length of the front section of thread is larger than that of the rear section of thread, the front section of thread is used for fastening the nut, the rear section of thread is used for locking, and the pitches of the two sections of threads are identical and the starting points are different. According to the locknut disclosed by the invention, when the bolt threads are screwed into the rear-section thread part, due to the fact that a certain amount of difference exists between the front thread starting point and the rear thread starting point, the gap between the bolt threads and the meshing part of the two sections of threads of the nut is eliminated after the bolt is screwed, the extrusion deformation and the friction resistance which are effectively formed exist together, the pretightening force is generated, and the expected force exists all the time after the nut is screwed, so that the locknut is capable of realizing the lockeffect.

Description

Pretightening force locknut

Technical Field

The invention belongs to the field of thread looseness prevention, and relates to a pretightening force locknut.

Background

The common nut locking modes are as follows: rivet-punching looseness prevention, mechanical looseness prevention, friction looseness prevention and the like. The rivet-punching anti-loosening mode has the defects that the bolt rod can only be used once, the disassembly is very difficult, and a bolt auxiliary part is required to be destroyed for disassembly.

The mechanical locking is not locked in practice but is prevented from falling off because the locking nut stop is not preloaded and the locking stop only acts when the locking nut is released to the stop position.

Friction locking is the most widely used locking means that creates a positive pressure between the lock nut pairs that does not vary with external forces to create a friction force that resists relative rotation of the lock nut pairs. This positive pressure can be accomplished by axially or simultaneously compressing the lock nut pair in both directions. If the elastic washer, the double nuts, the self-locking nuts, the insert locking nuts and the like are adopted, a plurality of parts are required to be combined for use, and the assembly and the disassembly are inconvenient.

Disclosure of Invention

The purpose of the invention is that: based on the friction anti-loosening principle, the pre-tightening force anti-loosening nut is simple in structure, reliable in loosening prevention, reusable and wide in application range.

Technical proposal

The technical solution of the invention is as follows: the pretightening force locknut is characterized in that the locknut internal thread consists of a front section and a rear section of continuous internal threads, the length of the front section of internal threads 11 is longer than that of the rear section of internal threads 12, and the pitches of the two sections of internal threads are the same and the thread starting points are different.

Furthermore, the lengths of the front section internal thread and the rear section internal thread are adapted according to the specification of the locknut.

Further, the thread start point angle variable of the front section internal thread and the rear section internal thread is within the range of 10 degrees to 120 degrees.

Furthermore, the difference of the pitch diameter sizes of the front section internal thread and the rear section internal thread is adapted according to the anti-loosening performance requirement.

Further, the metal-nonmetal composite material is made of metal and nonmetal materials with certain strength.

Further, the metallic material is preferably 40Cr steel.

Further, the shape of the locknut is selected according to the requirement, and is preferably hexagonal.

Technical effects

According to the locknut disclosed by the invention, when the bolt is screwed into the inner thread 12 part of the rear section of the nut, due to the fact that a certain amount of difference exists between the front inner thread starting point and the rear inner thread starting point of the nut, the clearance between the outer thread 2 of the bolt and the meshing part 3 of the two sections of inner threads of the nut is eliminated after the bolt is screwed into the nut, the extrusion deformation and the friction resistance which are effectively formed exist together, a certain pretightening force is generated, and the pretightening force for clamping a workpiece after the nut is screwed up also exists all the time, so that the locknut is realized.

Drawings

FIG. 1 is a schematic view of a locknut;

FIG. 2 is a schematic view of a locknut and bolt connection thread;

the marks in the figure are: 1. a locknut body; 2. a bolt external thread; 3. a thread engagement surface; 4, workpiece to be clamped; 11. front section internal thread; 12. and the rear section is internally threaded.

Detailed Description

The invention is further described below with reference to examples. The following description is of some, but not all embodiments of the invention. All other embodiments, which can be made by those skilled in the art based on the embodiments of the invention without making any inventive effort, are intended to be within the scope of the invention.

The following is a further description of the practice of the invention with reference to the accompanying drawings.

When the nut blank is used for processing an inner hole thread, two sections of inner threads with the same thread pitch are formed in the inner hole of the nut according to the specification or the anti-loosening performance of the nut, the length of the front section inner thread 11 is 2/3 of the total length of the inner thread, the middle diameter size of the rear section inner thread 12 is the same as that of the front section inner thread 11, and the starting point position of the thread is different from that of the front section inner thread 11 by 30 degrees.

When the inner thread 12 of the rear section is partially screwed into the outer thread 2 of the bolt, the gap between the outer thread 2 of the bolt and the meshing part 3 of the inner threads of the front section and the rear section of the nut is eliminated because of the 30-degree difference between the starting points of the inner threads of the front section and the rear section of the bolt, the extrusion deformation and the friction resistance which are effectively formed exist together, a certain pretightening force is generated, and the pretightening force of a compressed workpiece still exists all the time after the nut is screwed, so that the anti-loosening purpose is realized.

While the foregoing is directed to embodiments of the present invention, other and further details of the invention may be had by the present invention, it should be understood that the foregoing description is merely illustrative of the present invention and that no limitations are intended to the scope of the invention, except insofar as modifications, equivalents, improvements or modifications are within the spirit and principles of the invention.

Claims

1. The pretightening force locknut is characterized in that the locknut internal thread consists of a front section and a rear section of continuous internal threads, the length of the front section of internal threads (11) is larger than that of the rear section of internal threads (12), the pitches of the two sections of internal threads are the same, and the thread starting points are different.

2. The pretension locknut of claim 1 wherein the length of the front and rear internal threads is adapted to locknut specifications.

3. The pretension locknut of claim 1, wherein the thread start angle variation of the front and rear internal threads is in the range of 10 ° -120 °.

4. The pretightening force locknut of claim 1, wherein the difference in pitch diameter size between the front and rear internal threads is adapted according to the lockperformance requirements.

5. The pretensioned locknut of claim 1 wherein the locknut is made of a metallic, non-metallic material having a certain strength.

6. A pretensioned locknut according to claim 5, characterized in that the metallic material is preferably 40Cr steel.

7. A pretensioning locknut according to claim 1, wherein the locknut profile is selected as desired, preferably hexagonal.