| 主权项 |
1. A broach comprising:
a shaft-shaped broach body; and a plurality of cutting edges that are arranged on an outer circumference of the broach body spaced apart at intervals in an axial direction of the broach body, wherein the broach body is inserted into a prepared hole that is formed in a work material facing a tool feed direction along the axial direction, and, the plurality of cutting edges groove the prepared hole or machine an inner circumference of the prepared hole, thereby cutting the prepared hole into a predetermined shape, the plurality of cutting edges are provided with a spline teeth group, which contains a plurality of spline teeth that groove the prepared hole, and a round teeth group, which is disposed in a different position from the spline teeth group along the axial direction and contains a plurality of round teeth that machine the inner circumference of the prepared hole, at least one gullet is formed to extend along the outer circumference of the broach body in the circumferential direction around an axis of the broach body between the round teeth that are adjacent to one another in the axial direction in the round teeth group; the gullet extends toward the axial direction, gradually twisting toward the circumferential direction; and the spline teeth group and the round teeth group are formed integrally on the outer circumference of the broach body. |
