GB495653A - Improvements in or relating to wall-plugs and the like fastenings - Google Patents

Abstract

495,653. Wall-plugs &c. DUNCAN, J. May 21, 1937, Nos. 14135 and 34831. [Class 89 (i)] A wall-plug or like fastening comprises a hollow, plug-like body 8 formed at its outer end with a recess 15 and at its inner end with expansible fingers 8a between radial slots 16 which extend longitudinally from the recess to the innermost end of the body, the bore of the latter being tapered to receive wedge means which expand the fingers 8a when moved by a bolt 10 or the like, the outer end of which is accommodated in the recess 15. The otherwise cylindrical bore may be formed with oppositely directed tapered surfaces 12, 14 adapted to be engaged, respectively, by a wedge 9 and a conical part 11 on the bolt, the wedge having one or more ribs 17 to engage the slots 16. The outer surface of the body 8 may be slightly tapered and may comprise a smooth outer portion 22 and an inner portion formed with annular buttress teeth 18 and longitudinal grooves 18a (not shown), the inner and outer portions being separated by an annular groove 19, or other zone of weakening, which facilitates outward expansion of the fingers 8a. One of the slots 16 may extend to the outermost end of the body 8. The latter may be flanged as at 23, whilst the bolt may be formed with a nut head 10b, for operation by a box key, and with a hold, such as a tapped hole 20, to receive a screw for attaching an external object to the wall-plug. Alternatively, a hook or the like may be provided on the body 8 or on the flange 23. The body 8 and bolt 10 may be made of steel and the wedge 9 of cast iron, or they may all be made of galvanized steel or phosphor bronze, whilst the teeth 18 may be case-hardened.