Knurling type anti-falling expansion bolt

Abstract

The invention discloses a knurling type anti-falling expansion bolt which comprises a bolt, a sleeve pipe, a gasket, a spring washer and an expansion nut. The sleeve pipe comprises a sleeve pipe bodywith a through hole formed in the middle and multiple clamp pieces located at the bottom of the sleeve body. A knurl is arranged at the top of the sleeve pipe body. Multiple first grooves which extendto the bottom end from the middle and penetrate through the pipe wall are formed in the outer wall of the sleeve pipe body. The expansion nut is in a circular table shape, and a threaded hole is formed in the middle of the expansion nut. The clamp pieces are obliquely arranged at the bottom of the sleeve pipe body, a flaring opening is formed, and the oblique angle of the clamp pieces is matchedwith the expansion nut. Multiple second grooves are formed in the inner walls, close to the bottom ends, of the clamp pieces, the clamp pieces can be bent inwards along the second grooves to form a cavity, and therefore the expansion nut is fixed inside. The expansion nut is prevented from falling, and meanwhile the expansion degree of the sleeve pipe can be adjusted.

Description

【Technical field】 [0001] The invention relates to the technical field of expansion bolts, in particular to the technical field of embossed anti-drop expansion bolts. 【Background technique】 [0002] Expansion bolts are generally composed of screw cylinders, expansion heads, expansion sleeves, nuts, washers and gaskets. According to the position of the nuts, they can be divided into nut external expansion bolts and nut internal expansion bolts. The nut-external expansion bolt refers to the form in which the nut is exposed to the outside, and the nut is screwed to tighten the expansion bolt; the nut-internal expansion bolt refers to the nut (that is, the expansion head) that is buried in the drilled hole of the wall or concrete. In the form of screwing the screw head at the end of the screw cylinder to tighten the expansion bolt. [0003] The current expansion bolts cannot be drilled deep or shallow during the installation process. Once the depth is drilled, for the nut-built-...

AI Technical Summary

Problems solved by technology

[0003] The current expansion bolts cannot be drilled deep or shallow during the installation process. Once the depth is drilled, for the nut-built-in expansion bolts, it is easy to make the nut (that is, the expansion head) fall into the drill hole, especially when the screw column It will be more likely to happen when the body is screwed in again, which will cause great inconvenience, and when screwing, the bolt (screw cylinder) and the nut will easily rotate together and cannot be tightened, which will affect the use of the expansion bolt

In addition, if the material of the ground or wall is relatively loose or the diameter of the drill bit used for drilling is too large, resulting in a clearance fit between the preset hole and the expansion sleeve, during the process of tightening the screw, the sleeve will rotate with the bolt rotation. Follow-up problems, resulting in unstable installation of equipment or devices

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