| 摘要 |
PROBLEM TO BE SOLVED: To provide a new cutting insert of a throw-away type with small- radius noses in which cutting grooves having cutting control ability in slight cutting with a very small feeding and cutting depth are formed for eliminating partial distortion of a thin member during machining. SOLUTION: Two curved portions formed on chipbreaker faces 46, 48 includes blade curved portions extending outside and backwardly from a ridge 52 to adjacent sides of a cutting insert. The chipbreaker faces 46, 48 are inclined upwardly from radius mixture portions 56, 58 to a flat portions 54 which is the highest portion on the upper face of the cutting insert. |
