摘要 |
The present invention relates to a cutting insert having cutting edge portions at intersection ridge portions between each of two end surfaces at the opposite side to each other and the peripheral side surface. Both the end surfaces are formed to be plane-symmetrical. In each end surface, long side portions and short side portions are alternately connected through raised corners or lowered corners. Each cutting edge portion is formed in regard to the raised corner, and has a corner cutting edge formed in the raised corner, a major cutting edge connected to the corner cutting edge and extending in the long side portion, and a minor cutting edge connected to the corner cutting edge at the opposite side and extending in the short side portion. |