CENTER LOCATING FEATURE IN DRILL BIT FORMED WITHOUT A POINTED TIP

摘要

A centering feature (230) on a drill bit (110) configured without a pointedtip, formed as an opening (230) betweenfirst (206) and second (208) relatively angularly inclined portions of a workengaging end (116) of the drill bit (110). The first portion(206) of the work engaging end (116) is defined by a cutting edge (134), andthe second portion (208) is defined by an end face sideboundary (216) transversely aligned with the cutting edge (134). The cuttingedge (134) and end face side boundary (216) are offsetfrom each other to create the opening (230), which permits the drill operatorto view a punch mark or other indication on the workpiece where the center (232) of the intended hole is to be located. The drilloperator positions the medial termination point (212) ofthe cutting edge (134) of the drill bit (110) over the center hole location(232) preparatory to contacting the drill bit (110) against thework piece to cut the hole.