Patent ID: 7077038
Filing Date: 2006-07-18
Classification: F16B

Abstract:
1. A screw, comprising: a screw head having a drive recess which is for engagement with a drive head of a driver bit; and a screw shank having threads and being integrally formed with the screw head, wherein the drive recess includes a plurality of engaging grooves equiangularly radiating from an axis of the screw in plan view, a cross section of a bottom face of each engaging groove cut along a plane including the axis of screw including a first straight line and a second straight line. a first portion of the first straight line is nearer to the screw shank than second straight line, and an inclination angle α of the second straight line to the axis of the screw is larger than an inclination angle β of the first straight line to the axis of the screw.