Patent ID: 8496414

Claim:
A clamping member for clamping a cutting insert on a tool holder, comprising: a body having a top surface engageable with a head of a clamping bolt, a bottom surface for facing the tool holder and a bolt hole for insertion of the clamping bolt, the bolt hole passing through between the top surface and the bottom surface; and a protrusion portion protruding from the bottom surface and engageable with a mounting hole formed in the cutting insert, wherein the protrusion portion has an inclined surface facing toward a rotational direction about a center axis of the clamping bolt; wherein: the inclined surface is inclined so that the protrusion portion is gradually tapered from a base side thereof proximate the bottom surface toward an end side thereof distal from the bottom surface; the inclined surface is smoothly and convexly curved in a circumferential direction of the protrusion portion, and is smoothly connected to an outer surface other than the inclined surface; and a cross section in a base portion of the protrusion portion has a substantially circular shape and a cross section in an end portion of the protrusion has a substantially elliptic shape having a major axis exending in a longitudinal direction of the clamping member.