Patent ID: 8137035

Claim:
A cutting insert comprising a rake face region located on an upper surface, a flank located on a front surface, and a cutting edge located at an intersection between the rake face region and the flank, wherein at least three types of projections having different distances from the cutting edge are located on the rake face region, and when the three types of projections are represented by a first projection, a second projection and a third projection in the order of their increasing distance from the cutting edge, the top portion of the second projection is located lower than an imaginary straight line connecting the top portion of the first projection and the top portion of the third projection in the side view, and wherein a clamp face region clamped by a holder is further located on the upper surface, and in the plane view, the rake face region and the clamp face region are arranged in this order from the cutting edge, and the rake face region comprises a edge closer to the clamp face region, and the edge of the rake face region inclines so as to have an increasing distance from the cutting edge, from one end of the cutting edge toward the other end of the cutting edge, in the plane view.