Patent ID: 8747043
Filing Date: 2014-06-10
Classification: B25B,E04B,F16B,Y10T

Abstract:
1. A fastener comprising: a head including a drive feature adapted to be driven by a tool to rotate the fastener; a shaft joined with and extending away from the head, the shaft terminating at an end, the shaft defining a longitudinal axis; a primary thread formed along the shaft, the primary thread coiling around the shaft toward the end, the primary thread including a last thread; and a chisel brake point located at the end, the chisel brake point including a first inclined surface and a second inclined surface that begin at a boundary and extend toward a chisel edge, wherein the last thread coils around the end, beyond the boundary toward the chisel edge, wherein the last thread merges with the first inclined surface to form an extension of the first inclined surface, thereby increasing a surface area of the first inclined surface, wherein the last thread includes a lower thread surface that is located within the end, wherein the lower thread surface coils around the shaft and joins with the primary thread so that material scraped at least by the chisel edge, while pre-boring a hole in a work piece with the fastener, is transferred to the last thread, and subsequently fed up the lower thread surface so that the material is moved from a bottom of the pre-bored hole and out of the pre-bored hole.