Patent ID: 8029215
Filing Date: 2011-10-04
Classification: B23B,B23P,B24B,Y10T

Abstract:
1. A drill bit for drilling holes of a plurality of diameters in a workpiece comprising: a generally conically-shaped main body including a tip, a rear wall, a central axis extending from said tip to said rear wall about which the drill bit is rotated, a first flute and a second flute each extending along a length of said main body, a first helical groove extending along said main body, said first helical groove including a plurality of first helical groove segments, a second helical groove extending along said main body, said second helical groove including a plurality of second helical groove segments, said first and second helical groove segments alternating along the length of said main body, and a cutting segment provided at least between adjacent ones of said first and second helical groove segments; and a shank extending rearwardly from said rear wall of said main body.