| 摘要 |
PROBLEM TO BE SOLVED: To provide a drilling tool for chip removing machine processing, and also to provide a loose top of the same, and further to provide a base body.SOLUTION: A branch (15) transmits torque to the loose top (2) through a contact surface (36) in the tangential direction and the inner support surface (17) of the branch is simultaneously elastically pressed to the outer contact surface (24) of the loose top to be held in order to firmly grasp it. When the loose top is mounted, the loose top is inserted in an axial direction between the branches (15) and a support surface (20) in the tangential direction is turned till it contacts with the contact surface (36) in the tangential direction of the loose top. In order to allow the loose top to be temporarily centered with coarse accuracy relative to turning in, protruding guide surfaces (the plural) (26) are formed at the loose top and they are arranged in the axial direction between a contact surface (11) in the axial direction and the outer contact surface (24). |
