To stably clamp a chip.
Constraint surfaces 33, 33 sides of a tapered surface 43 formed on a head 42 of a clamp screw 40 press constraint surfaces 33, 33 sides of a tapered surface 56 formed in an insertion hole 55 of a chip element 50 by coming into surface contact with the constraint surfaces 33, 33 sides of the tapered surface 56. In a cross sectional view including tips of cutting edges 54, 54 of the chip element 50 and an axis R of the insertion hole 55, the contact surface of the tapered surface 43 of the head 42 of the clamp screw 40 with the tapered surface 56 of the insertion hole 55 of the chip element 50 is positioned on almost the same straight line as a straight line AE connecting a fulcrum A for a force F1 lifting the chip element 50, with the end point E of the contact surface at the constraint surfaces 33, 33 sides, when the cutting force P is applied to the tips of the cutting edges 54, 54.
ENDO KUNIHIRO
WATANABE SHOICHIRO
Tadashi Takahashi
Masakazu Aoyama
Akihiko Eguchi
Hideyuki Sugiura
Yasuhiko Murayama
Noriko Yanai
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