Patent ID: 8491230

Claim:
An insert clamp for securing a cutting insert to a tool holder, the cutting insert having a central hole with its axis perpendicular to an upper surface, comprising: a forward protrusion to be received in the central hole of the insert, a central body portion provided with a pressing part to press down the upper surface of the insert and a screw hole for a clamping screw to pass through, and a rear protrusion having a rear contact surface to come in contact with a rearward slanting surface of the tool holder; wherein: the forward protrusion is formed on the forward end of the insert clamp, an inside surface of the forward protrusion extends downward in a spaced state apart from the inner wall of the central hole of the insert, and a distal portion of the inside surface of the forward protrusion is provided with a protuberance of convex curved surface to come in tangential contact with the inner wall of the insert; and the pressing part is formed on the bottom surface of the central body portion of the insert clamp, and has convex curved surfaces to come in tangential contact with the upper surface of the insert on both regions of the bottom surface of the central body portion which is bisected by a central line (L) passing through the forward protrusion and the screw hole.