Patent ID: 8851810

Claim:
A cutting tool, comprising: a cutting insert comprising a body part in a polygonal plate shape, a cutting edge located along an intersection of an upper surface and a side surface of the body part; and a holder comprising an insert pocket for attaching the cutting insert at a front end part of the holder, wherein the insert pocket comprises a seating part comprising a seating face which is brought into contact with a lower surface of the cutting insert, and is inclined forward in a rotation direction of the holder as the seating face extends away from the front end part of the holder, and a constraining part configured to be brought into contact with a first side surface and a second side surface adjacent to each other along the side surface of the body part, the constraining part comprises a curved portion, a first constraining face which is connected to one end of the curved portion, and extends perpendicularly with respect to the rotation axis of the holder or extends away from the front end part of the holder as the first constraining face extends away from the curved portion, and a second constraining face which is connected to the other end of the curved portion, extends toward the front end part of the holder as the second constraining face extends away from the curved portion and extends toward the rotation axis from an end portion close to the curved portion.