| 摘要 |
PURPOSE:To perform cutting by using either of two eccentric cutting edges without causing interaction between them, by making a parallel side face, that is useful as a flank at the starting point of the edge, at the crossing of both edges. CONSTITUTION:The cutting edge 14 of a throw-away tip 3 is formed as two independent edges which are eccentric to each other, and a parallel side face 15 is formed at their crossing, so that it functions as a flank for the starting point 16 of the edge when it is on a tip seat 2 to perform cutting by using only either one of the edges 14 without causing any interaction between them. A square projection supported by a concave 6 on the tip seat 2 is formed on the rear side of a flank 10 of the throw-away tip 3 to prevent the tip from falling off the seat 2 because of cutting resistance imposed on the tip in various directions and also to improve its fitting strength. |
