| 摘要 |
This insert-type cutting tool (1) includes: an insert (20) formed as a flat polygonal plate, and which has an upper surface (21) formed as a rake surface and a lower surface (22); a tool main body (10) which has a recessed portion (13) formed on an outer side surface of a head portion (12) of the tool main body (10); and an insert seat (14) formed on a wall surface of the recessed portion (13) facing in a normal rotation direction of the tool main body (10), and to which the insert (20) is attached so that the upper surface (21) of the insert (20) faces in the normal rotation direction of the tool main body (10). A first through-hole (31A) and a second through-hole (31B) are formed in the insert (20). A first screw hole (15A) and a second screw hole (15B) are formed in the insert seat (14) of the tool main body (10) so that the first screw hole (15A) is separated from the second screw hole (15B) in an axial direction of the tool main body (10). The insert (20) is mounted on the insert seat (14) so that the center of the first screw hole (15A) is located closer to the axis (O) and to the base end of the tool main body (10) than the center of the first through-hole (31A), and the center of the second screw hole (15B) is located closer to the axis (O) and closer to the base end of the tool main body (10) than a center of the second through-hole (31B). A first inclination angle ¸1 formed by the intersection of a straight line passing trough the centre of the first screw hole (15A) and the center of the first through-hole (31A) with the axis (O) is less than or equal to a second inclination angle ¸2 formed by the intersection of a straight line passing through the center of the second screw hole (15B) and the center of the second through-hole (31B) with the axis (O). |
