| 摘要 |
<p>A tip (30) comprises a generally square lower surface (30a), clearing flanks (33) formed on a projecting curved surface-like upper surface (30c) raised upward from two opposed sides (30b) of the square surface, a pair of rake faces (32) formed on first side surfaces (30e) raised upward from the remaining two opposed sides (30d) of the square surface and crossing the projecting curved surface, a pair of corner edges (31) each formed at a ridge at which a rake face (32) and a clearing flank (33) cross each other, and a pair of second side surfaces (30f) which, when viewed from the direction orthogonal to the lower surface (30a), is formed so as to obliquely cross the opposed two sides (30b) of the square surface, is raised upward from the lower surface (30a), and cuts out a section at which the lower surface (30a) and the upper surface (30c) cross each other. In indexing an acting corner edge (31a) and an acting face (32a) which connects to the acting corner edge, the first side surfaces (30e) as non-acting faces (32b), the second side surfaces (30f) adjacent to the acting corner edge (31a), and the lower surface (30a) are restrained on a seating surface of a tip seat (51).</p> |
