Patent ID: 6872042
Filing Date: 2005-03-29
Classification: F16B,Y10S

Abstract:
1. A fastener for removably fastening a work piece to a steel member comprising: an elongate shank having an axis, a head for receiving an axial impact for driving said fastener axially forwardly, said head having a recess for receiving a rotary driver, and a generally pointed tip; said shank having generally helical grooves for imparting clockwise rotation as said fastener is driven axially forwardly, wherein said generally helical grooves intersect generally annular grooves defining knurls, a plurality of said knurls each including a trailing portion angled no more than about 20 degrees from normal for increased pullout strength, a lateral cutting edge for cutting away said steel member when said fastener is rotated in a counterclockwise direction by said rotary driver, and an axially leading portion angled between about 60 degrees and about 70 degrees from normal and tapered toward said generally pointed tip.