CUTTING TOOL

PROBLEM TO BE SOLVED: To increase fixing force of a cutting insert in a cutting tool having a structure fixed by positioning by pushing the cutting insert to the restricting wall side by a clamping disc screw. SOLUTION: A projecting round part 35 is formed at an angle formed by a tapered seat 17 for receiving a disc part 34 of a head part 33 of the clamping disc screw 31 in a clamping hole of the cutting insert 11 and a hole part 15 for inserting a shaft part 32 of the disc screw 31. While, a recessed round part 35 having a radius larger than the projecting round part 18, is formed in the corner between the shaft part 32 in the disc screw 31 and the disc part 34 of the head part 33. When viewed in a cross-section including the axis of the disc screw 31, a fixation by pressing a side surface of the cutting insert 11 to a restricting wall by screwing in the disc screw 31, is performed by bringing a surface of the recessed round part 35 of the disc screw 31 into pressure contact with a surface of the projecting round part 18 in the clamping hole. The fixing force is increased due to becoming wide pressure contact of a contact surface without becoming spotted contact. COPYRIGHT: (C)2005,JPO&NCIPI