摘要 |
A cutting insert is provided with an upper surface, a lower surface, side surfaces for interconnecting the upper surface and the lower surface, cutting edges located at the intersections between the upper surface and the side surfaces, and grooves located in the side surfaces, extending from the upper surface toward the lower surface, and dividing the cutting edges. Each of the grooves is provided with a first edge and a second edge which are located at the edges of the groove in the width direction thereof and extending from the upper surface toward the lower surface. In a side view, the first edge has a first separated section located on the upper surface side and, as the first edge extends toward the lower surface, separated away from a reference line which passes through the midpoint of the groove in the width direction thereof and is substantially perpendicular to the lower surface. Also, in the side view, the second edge has a second separated section located on the upper surface side and separated away from the reference line as the second edge extends toward the lower surface. |