| 摘要 |
PURPOSE: To provide an exchangeble cutting insert capable of cutting each recessed part having a wall perpendicular to one another, by mounting each secondary cutting edge in such manner that it does not project beyond its associated main cutting edge in the direction of a rake surface. CONSTITUTION: Each recessed valley part 7 is formed on a rake surface 2 adjacent to an insert corner 6 and united with a right end of each main cutting edge 5. The valley part 7 has a bottom surface 8 intersecting a secondary rake surface 9 on a secondary cutting edge 10. A degree of displacement of the secondary cutting edge 10 toward a bottom edge 4 to the main. cutting edge 5 and a degree of the outward displacement to the main rake surface to which the secondary cutting edge 10 is adjacent are determined so that each secondary cutting edge 10 does not project beyond its associated main cutting edge 5 when an insert is viewed from an upper portion in the direction of the rake surface 2. |
