Patent ID: 6786684
Filing Date: 2004-09-07
Classification: B23B,Y10T

Abstract:
A tubular hole cutter comprising:a. a backing plate; b. a tubular side wall attached to the backing plate and having a generally smooth, annular end surface opposite said backing plate, wherein the annular end surface is interrupted by three generally longitudinal gullets in the tubular side wall, said gullets being equally spaced about the circumference of the tubular side wall; and c. three cutting bits attached to the tubular side wall at respective trailing edges of said gullets, wherein the cutting bits: (i) extend past the trailing edges of the gullets in the direction of rotation of the tubular hole cutter; (ii) extend longitudinally past said annular end surface; and (iii) each have: a rake angle; a top relief; two side reliefs; and two radial reliefs, to provide a balanced, clean cut in a work piece.