Detachable expansion screw

Abstract

The invention relates to a detachable expansion screw comprising a casing and a screw. An inner thread matched with an outer thread of the screw is arranged on the inner circumferential wall of the casing. A front end inner cavity of the casing is conical. Expansion ceilings are evenly distributed on the front end circumferential wall of the casing in the axial direction. The parts, between adjacent expansion ceilings, of the casing form expansion strips. An expansion groove communicating with the expansion ceilings is formed in the middle circumferential wall of the casing. A conical tip corresponding to the cone of the casing is arranged at the front end of the screw. An inside-to-outside expansion mode is adopted for the detachable expansion screw, the expansion strips can be stretchedby a larger angle, the expansion diameter is larger, thus the casing is connected more firmly and is not liable to falling off, a large weight can be borne, and object use safety is ensured. When screwed tightly, the screw moves towards the inside of a building. After the expansion screw is installed, little part of the screw is exposed, and thus a wall is attractive in appearance. When the expansion screw needs to be detached, the screw is retracted till a tension sense disappears, supporting force is lost in the casing, in this way, the expansion strips are taken back, then a threaded rod and a sleeve are pulled out together, the expansion screw can be taken out easily and can be recycled, and resources are saved.

Description

technical field [0001] The invention relates to the technical field of fasteners, in particular to a detachable expansion nail. Background technique [0002] In the field of fasteners, expansion nails are widely used. For example, when installing other hanging objects on the walls, beams, columns, etc. of buildings, it is generally necessary to drill holes in the positions required by the building, and then install expansion nails in the holes. , and then fix other hanging objects on the expansion nails. Currently common expansion nails are composed of a screw and an outer sleeve. Expansion joints are provided on the sleeve. The volume of the sleeve can be changed by changing the relative position of the screw and the sleeve to achieve the purpose of fixation. Existing expansion nails generally deform the casing by squeezing both ends inward and then expand the casing to fasten the casing in the hole. This kind of expansion nail encounters soft and low-density walls such as...

AI Technical Summary

Problems solved by technology

Existing expansion nails generally deform the casing by squeezing both ends inward and then expand the casing to fasten the casing in the hole. This kind of expansion nail encounters soft and low-density walls such as foam bricks and gypsum boards. Walls, hollow bricks, etc. are almost useless. It is very difficult to disassemble the expansion nails after use. The disassembly process easily deforms the screws and cannot be reused. It is a waste of resources, and the expansion nails are stuck on the wall, which affects the decoration effect and is not beautiful.

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