Die for, method of making, and fastener with lobed primary thread lead and interposed dual auxiliary thread lead with improved substrate entry end portion

摘要

A threaded fastener comprises a first, primary thread lead, and a pair of second, auxiliary thread leads alternatively interposed between successive threads of the first, primary thread lead, except within the vicinity of the tip portion of the fastener so as to define space for accommodating debris generated during the self-tapping of the fastener into a workpiece. The fastener also comprises lobe members formed upon the primary thread lead so as to predeterminedly affect torque insertion and pull-out resistance values.