Expansible anchor

Claim 1

An expansible anchor for use in mounting an object in an anchoring hole of a support structure, comprising an expander member having a screw-threaded trailing shaft portion and a leading expander portion diverging forwardly from the same; an expansion sleeve slidably surrounding said shaft portion over part of the length thereof and having a trailing end constituted of metallic material; an actuating member having a front annular end face constituted of metallic material; and a tapped bore into which said shaft portion is threaded, and which extends rearwardly from said front annular end face; and a cap formed of synthetic plastic material having a skirt portion of an outside diameter larger than the diameter of said trailing end of said sleeve so as to surround the latter, and a confined transverse portion extending inwardly of said skirt and surrounding said shaft portion, said transverse portion being located intermediate said metallic material trailing end of said expansion sleeve and said metallic material front annular end face of said actuating member so as to prevent metal-to-metal contact therewith so that, on requisite turning of said actuating member, said front annular end face bears against said transverse portion and via the same upon said trailing end of said expansion sleeve to effect relative movement of the same and of said expander member, thereby resulting in entry of said leading expander portion into said sleeve and consequent expansion of the same.