ROTARY CUTTING TOOL

PROBLEM TO BE SOLVED: To provide a rotary cutting tool equipped with very high excellency in the practical applicability, capable of ejecting the cutting chips in good performance even at the time of processing in vertical feeding and of hindering the chips from causing clogging as much as practicable. SOLUTION: The rotary cutting tool is configured so that a number of spiral chip ejecting grooves 2 are formed at the tip periphery of the tool body 1 assuming approximately a columnar shape and a bottom cutting edge is provided at the intersecting ridge part between the rake surface 3 of each chip ejecting groove 2 and the tip clearance surface of the tool body 1, wherein at least one of the bottom cutting edges is furnished with a non-cutting part 22 in which that part of the cutting edge positioned nearer the tool periphery immerses in the axial direction of the tool body 1. COPYRIGHT: (C)2008,JPO&INPIT