| 摘要 |
The present invention is a radius end mill (10) equipped with end cutting edges (7) formed so that the rotation tracks thereof around the axial line (O) trace a convex surface. The convex surface is formed so that in cross-sectional view along the axial line, the convex surface has a convex line such that the radius of curvature at the inner portion (7A), which is located closer to the axial line than the tip periphery (7B) of the end mill body (1), is larger than the radius of curvature at the tip periphery. The gash depth angle θ (°) calculated from θ = tan-1 (A/B) based on the distance A (mm) from the tip (7A) of the end cutting edge to the rearmost edge of a gash (6) in the axial direction and the radius B (mm) from the axial line to the point of contact (7B) between the peripheral cutting edge (5) and the end cutting edge is set to be not more than 50°. The sum (θ (°) + α (°)) of the gash depth angle θ (°) and the axial direction rake angle difference α (°) = (α2 (°) - α1 (°)) between the axial direction rake angle α2 (°) of the end cutting edge at the point of contact and the axial direction rake angle α1 (°) of the end cutting edge at the tip is set to be at least 60°. |
