Patent ID: 7866924

Claim:
A clamping mechanism for clamping a cutting insert by inserting the cutting insert into an insert mounting seat at a holder, the clamping mechanism comprising: the holder having an upper jaw and a lower jaw at a tip of the holder, a first contacting surface and a second contacting surface as the insert mounting seat, the first contacting surface and the second contacting surface facing each other, the first surface being provided at either one of the upper or the lower jaw, the second surface being provided at the other of the upper or the lower jaw; the cutting insert having first and second contact surfaces which contact with the first and second contacting surfaces of the holder respectively; wherein one of the first contacting surface or the first contact surface has a concave V-shape and the other has a convex V-shape, in a cross-section orthogonal to a longitudinal direction of the cutting insert; the concave V-shape consists of inclined left and right round faces that each bulge out, and a connecting recess provided where the left and right round faces meet; the convex V-shape includes inclined left and right planes and a connecting plane provided where the left and right planes meet; and the inclined left and right round faces and the inclined left and right planes come to contact at a first pair of contacting positions.