US 5,806,275 A · Chemical anchor bolt and cap assembly

Abstract

A chemical anchor bolt and cap assembly installable in a hole drilled in masonry to tightly fasten a fixture thereto and to resist loosening of the fastening should the masonry be subjected to vibratory or other external forces. The assembly includes a bolt having an externally-threaded cylindrical shank coated with a release agent and a thin-walled hollow cap having a non-cylindrical shape coupled to the end of the shank and extending therefrom in axial alignment with the shank. To install the assembly, the shank and the cap coupled thereto are inserted through a mounting hole in the fixture into the masonry hole in which is deposited an uncured epoxy that then surrounds the cap and the shank. When the epoxy hardens, formed therein is a female thread matching the release-coated male thread of the shank so that the bolt is now turnable, the cap being then embedded in the epoxy. As a consequence, formed in the masonry hole below the end of the shank is a hard epoxy column having a non-cylindrical cavity whose epoxy bank is defined and lined by the non-cylindrical cap to create a partial barrier to the unimpeded advance of the shank. To tighten the fastening, the bolt is turned to advance the end of the shank into the cavity, the shank then overcoming the partial barrier by cutting into and tapping the lined epoxy bank. The resultant frictional engagement between the end of the shank and the partial barrier acts to resist loosening of the fastening.

Claims14

Dependent claims

A chemical anchor bolt and cap assembly installable in a hole drilled in masonry having a charge of a hardenable bonding agent, deposited therein which when hardened acts to produce a fastening to tightly fasten a fixture or other object having a mounting hole to the masonry and to resist loosening of the fastening should the masonry be subjected to external forces;

said assembly comprising:
A. a bolt provided with an externally-threaded cylindrical shank extending from a head, said shank having a predetermined diameter and being coated with a release agent;
and
B. a cap coupled to an end of the shank and extending therefrom said cap having a shape whose geometry is such that at least one internal straight line passing through an axis of the cap is shorter than the diameter of the shank whereby when the shank and the cap coupled thereto are inserted through the fixture mounting hole into the masonry hole and the bonding agent hardens, then a female thread is formed in the bonding agent that matches the thread of the shank to permit the bolt to turn, and a bonding agent column is formed below the end of the shank having a cavity therein defined by the shape of the cap embedded in the column, said cavity having a bonding agent bank lined by the cap which creates a partial barrier to an unimpeded advance of the shank, whereby to tighten the fastening the bolt is turned in to advance the end of the shank to overcome the partial barrier by cutting into the lined bank, the resultant frictional engagement between the end of the shank and the partial barrier resisting turning out of the bolt and loosening of the fastening.

1 more element

Dependencies are inferred from the claim text.

Chemical anchor bolt and cap assembly

Life of this patent

Chemical anchor bolt and cap assembly

Life of this patent

Abstract

Claims14