Expansion bolt structure

Abstract

The invention relates to the field of fastening parts, in particular to an expansion bolt structure for uniformly expanding an expansion shell to effectively scattering anchoring force to improve theanchoring force and the durability of the expansion bolt. The expansion bolt structure comprises a bolt main body consisting of a thread section and an expansion bolt section; an expansion shell structure sleeves the expansion bolt section; a screw cap structure sleeves the thread section; the wall thickness of the expansion shell structure is gradually increased in a direction from the expansionbolt section to the thread section; and the inner wall surface of the expansion shell structure is tightly bonded with the outer wall surface of the expansion bolt section. The expansion bolt structure effectively overcomes the defects of low tightening force and easy failure of a traditional bolt structure, can be applied to anchoring structures with higher tightening force requirements more widely, and in particular, is suitable for tightening of objects with higher anchoring force requirements on such materials as cement and bricks.

Description

technical field [0001] The invention relates to the field of fastening parts, in particular to an expansion bolt structure. Background technique [0002] The fixing of the expansion screw is to use the inclination of the shape to promote the expansion to generate friction and grip force, so as to achieve the fixing effect. One end of the bolt is threaded, and the other end has a degree of taper. Wrap an iron cylinder on the outside. There are several cuts in the half of the iron cylinder. Put them together into the hole punched in the wall, and then lock the nut. The nut pulls the screw outward and pulls the vertebra into the iron cylinder. The cylinder is stretched out, so it is firmly fixed to the wall. Ordinary expansion bolts have two disadvantages. (1) The iron sheets of ordinary expansion bolts are of equal thickness, and the bolts have a large slope. When the bolts are under expansion force, there are lines between the screw rod and the expansion shell of the iron ...

AI Technical Summary

Problems solved by technology

The structure of ordinary expansion bolts leads to excessive local stress on the hole wall, and the material of the hole wall is prone to plastic failure, resulting in loss of expansion force and loosening of the bolts.

(2) Ordinary expansion bolts When the end of the vertebral body enters the iron expansion shell, the maximum expansion diameter of the entire screw will appear. After tightening the bolts, the outside of the iron expansion shell will not increase directly, but the position will follow the tightening of the bolts. Move, when the bolt is tightened, the screw rod is pulled out very long, but the tightening force cannot be effectively improved

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