| 摘要 |
The present invention provides a tool body (20) for a cutting edge exchange-type rotary cutting tool, the tool body having a substantially cylindrical shape and a rotational center axis. On the outer circumferential surface (23) of the tool body, a spiral groove (28) is formed so as to extend from the base end-side toward the tip end-side of the tool body. The spiral groove (28) is provided with a plurality of insert seats (30) disposed and formed so as to be offset from each other from the base end-side toward the tip end-side. The insert seats (30) are provided with a bottom surface (31) and first and second lateral surfaces (32, 33) that extend so as to be orthogonal to the bottom surface (31). The first lateral surface (32) faces the base end-side of the tool body (20), and the second lateral surface (33) faces the tip end-side of the tool body (20) and is positioned more toward the base end-side than the first lateral surface (32). With respect to at least one insert seat (30) positioned more toward the base end-side of the tool body (20) than an insert seat positioned at the most tip-end-side of the tool body, the length L1 of the first lateral surface (32) is longer than the length L2 of the second lateral surface (33). |
