Patent ID: 7165925
Filing Date: 2007-01-23
Classification: F16B,Y10S

Abstract:
1. An expandable fastener assembly for insertion into a substrate, comprising: (a) a threaded fastener having a proximal end and a distal end, the proximal end being provided with a head having turning means, the fastener having a shank extending from the head to the distal end along a longitudinal axis, the shank being provided with double interleaved helical threads extending radially outwardly from the shank, each of said threads having a first surface generally facing the distal end or a second surface generally facing the proximal end, or both and each double interleaved helical thread pair being either proximal or distal; and (b) a continuous, expandable helical coil member wound around the shank of the threaded fastener, between each of the double interleaved helical thread pairs, the coil member having a radially inwardly facing portion and a radially outwardly facing portion with a thread-contacting surface extending between the inwardly and outwardly facing portions and generally facing the distal end of the fastener or may in other embodiments be generally facing the proximal end of the fastener, wherein, prior to insertion of the fastener assembly into the substrate, the coil member is in a radially compressed form; and (c) releasable securing means by which the coil member is releasably secured in its radially compressed form, along at least a portion of its length, to the shank of the fastener, wherein the releasable securing means maintains connection between the coil member and the fastener, thereby maintaining the coil member in its radially compressed form at least until that part of the fastener assembly that is so compressed is completely or substantially completely threaded into the substrate.