CN2900898Y

CN2900898Y - Anti-loose screw structure

Info

Publication number: CN2900898Y
Application number: CN 200620046776
Authority: CN
Inventors: 沈金对
Original assignee: SHANGHAI LIANYING SCREWS Co Ltd
Current assignee: SHANGHAI LIANYING SCREWS Co Ltd
Priority date: 2006-10-13
Filing date: 2006-10-13
Publication date: 2007-05-16
Anticipated expiration: 2016-10-13

Abstract

The utility model discloses a release-avoided screw structure comprising a cap nut and a bolt wherein threads are distributed on the bolt, the section configuration of the thread in the bolt is a square and the shape change into a equiangular triangle after both equilateral sides extended and intersected, thereby, passive locking thread is point contacted with the thread in the bolt, the vibration force from the 30DEG C passive locking thread can be changed into the up pull force, thereby, the frictional force is improved and loosening can be avoided. The utility model has advantages of simple structure, convenient usage and not easy to drop.

Description

Anti-loose screw structural

Technical field

This practicality newly relates to a kind of fastening piece, relates to specifically a kind ofly the time preventing the screw that comes off in vibrations.

Background technique

As the screw of fastening piece, its most important performance is that its antidetonation is anti-loose performance, because normal screws commonly used is when locking, its screw thread mountain is a thread form with by the latch fitting screw-thread fit time, be parallel contact, sliding easily when vibrations gets loose, as shown in Figures 1 and 2.Method commonly used is the friction system commentaries on classics that increases the thread engagement intermountain, and as making a part of screw thread mountain distortion of screw earlier, soft thing is perhaps put into to stop screw thread rotation in the screw thread intermountain in powerful locking screw mountain, is coated with solid in addition on the screw thread mountain, and the locking back is fixing.Wherein on the screw thread mountain, be coated with solid owing to need not process without peculiar part and can realize, therefore often be used now, but also there is shortcoming in this method, as increase the assembling work time, pot life system condition increases, as according to the field of employment, select the solid of water-fast or oil resistance, heat resistance, winter hardiness, and will consider that incendivity in the operation is to the restrictive conditions such as Security of human body.

Summary of the invention

At the deficiency that prior art exists, order of the present utility model is to provide a kind of screw structure of becoming flexible of preventing when vibrations.

Goal of the invention of the present utility model is achieved by the following technical solution:

A kind of anti-loose screw structural comprises screw cap and lead screw, is evenly distributed with screw thread on the lead screw, and the section configuration on the screw thread mountain on the described lead screw is a quadrilateral, and its shape of the crossing back of prolongation, both sides that the length of side equates becomes nearly equilateral triangle.Like this when screw is locked screw-threaded coupling with quilt, a bit with by the lock screw thread contacting of mountain top, screw thread mountain, the disconnected point of contact blocks by the lock screw thread with 85～90 ° of forms, make like this along being passed the vibration force of coming and change into pulling force upwards, thereby increased frictional force and be not easy to become flexible by the angle of lock screw thread 30 degree.

It is loosening to prove further that by Fig. 8 and Fig. 9 screw structural of the present utility model is difficult for:

Among Fig. 8: release force=pulling force * COS (65+ α)＜COS60 * pulling force

(u is a friction factor)

Compare with regular screw threads, the utility model screw thread is under the condition of equal pulling force, and release force is less than the release force of common thread, this just mean need be bigger release force just can get loose.

Among Fig. 9:

Release force=vibration release force * COS (5+ α)＜vibration release force that vibration force transforms

Pulling force=vibration release force * COS60=1/2 that the vibration release force transforms vibrates release force

(u is a friction factor)

In vibration gets loose simulation test, vibration force one regularly, the vibration release force also is certain, but the release force that vibration force transforms on the new screw tooth form of this practicality is less than the vibration release force, and frictional force has also increased, and is greater than the tooth form of normal screws from the anti-loosing effect of face the utility model screw tooth form.

The section configuration on the screw thread mountain of screw of the present utility model is near equilateral triangle, just angle is outwardly cut away by level, like this with by the lock screw thread for some contact, make along being passed the vibration force of coming and change into the pulling force that makes progress, thereby increased frictional force and be not easy to become flexible by the angle of lock screw thread 30 degree.Advantage such as that screw structural of the present utility model has is simple in structure, easy to use, be not easy to come off.

Description of drawings

Fig. 1 is the amplification assumption diagram of normal screws section thread form;

The section of structure that Fig. 2 is a normal screws when being locked by latch fitting;

Fig. 3 is a normal screws when being locked by latch fitting, screw thread and the angular dependence figure that is contacted by the latch fitting screw thread;

Fig. 4 is the utility model screw structural figure;

Fig. 5 is an A portion thread form amplification assumption diagram among Fig. 4;

The section of structure that Fig. 6 is the utility model screw when being locked by latch fitting;

Fig. 7 is the utility model screw when being locked by latch fitting, screw thread and the angular dependence figure that is contacted by the latch fitting screw thread.

Fig. 8 is the utility model screw when being locked by latch fitting, release force, pulling force and pressure and frictional force graph of a relation;

Fig. 9 is the utility model screw when being locked by latch fitting, at the graph of a relation that various power under the vibration force are arranged.

The number in the figure explanation:

The tetragonal both sides of 1-screw cap 2-lead screw 3-screw thread mountain 4-

The disconnected sharp 6-of 5-is locked screw thread 7-screw 8-by latch fitting

Embodiment

How further specify the utility model below in conjunction with accompanying drawing 4-Fig. 7 realizes:

A kind of anti-loose screw 7 comprises screw cap 1 and lead screw 2, is evenly distributed with screw thread (as shown in Figure 4) on the lead screw 2; The section configuration on the screw thread mountain 3 on the described lead screw 2 is a quadrilateral, and its shape of the crossing back of 4 prolongations, both sides that the length of side equates becomes nearly equilateral triangle (as shown in Figure 5).

As shown in Figure 6, during at screw 7 and by latch fitting 8 lockings, screw thread mountain 3 has only any to contact with 25-α degree angle (wherein α is the 0-25 degree) with the 30 degree angles of being locked screw thread 6, the contact disconnected sharp 5 with 85～90 ° of forms block by the lock screw thread, make like this along being passed the vibration force of coming and change into pulling force upwards, thereby increased frictional force and be not easy to become flexible (as shown in Figure 7) by the angle of lock screw thread 30 degree.

Claims

1, a kind of anti-loose screw structural, comprise screw cap (1) and lead screw (2), lead screw is evenly distributed with screw thread on (2), it is characterized in that: the section configuration on the screw thread mountain (3) on the described lead screw (2) is a quadrilateral, and the crossing back of both sides (4) prolongation that the length of side equates is nearly equilateral triangle.

2, a kind of anti-loose screw structural according to claim 1, it is characterized in that: described screw (7) is with by latch fitting (8) screw-threaded coupling the time, screw thread mountain (3) is the some contact with being contacted by the lock screw thread, and the point (5) that breaks blocks by lock screw thread (6) with 85～90 ° of forms.