Clamping device for cutting insert, cutting tool, and cutting insert

A clamp member for clamping a cutting insert in a tool body, the clamp member comprising:

• a clamp portion provided with an insert contact surface;
• and
• a main portion connected to the clamp portion and comprising:
• opposing first and second contact surfaces;
• a long hole having a central axis line and extending between the first and second contact surfaces, the long hole comprising a first insertion portion and a second insertion portion connected to the first insertion portion, the first insertion portion being wider than the second insertion portion and further from the clamp portion than the second insertion portion;
• a first screw engagement surface formed in a periphery of the second insertion portion on a side of the first contact surface;
• and
• a second screw engagement surface formed in a periphery of the second insertion portion on a side of the second contact surface;
• wherein:
• the first and second screw engagement surfaces are arranged in a direction substantially orthogonal to the central axis line;
• and
• the first and second contact surfaces are constituted by planes and inclined with respect to the first and second screw engagement surfaces, respectively.

A double-sided cutting insert comprising:

• mutually opposing upper and lower surfaces;
• a side surface extending between the upper and lower surfaces;
• and
• a mounting hole penetrating the upper and lower surfaces and having a central axis line (CA) passing through the upper and lower surfaces;
• the mounting hole having a polygonal inner peripheral surface defined by a plurality of indexable surfaces, each configured for regulating a direction of seating of the cutting insert;
• the indexable surfaces being rotationally symmetric with respect to the central axis line (CA);
• the indexable surfaces being 180° rotationally symmetric with respect to a transverse axis line (TA) passing midway between the upper and lower surfaces of the cutting insert;
• and
• the indexable surfaces being minor symmetric with respect to a plane defined by the transverse axis line (TA) and the central axis line (CA).