| 摘要 |
<p>Provided is a ball end mill that does not interfere with the defect resistance of the cutting blade, the rotational track of which forms a convex hemispherical shape. A ball end mill in which a gash (4) is formed on the tip of a main end mill body (1) that is rotated around an axis line (O) and a cutting edge (5), the rotational track around the axis line (O) of which forms a convex hemispherical shape having a center (C) on the axis line (O), is formed on the edge of the gash (4) wall surface (4A) that faces in the end mill rotation direction (T). In the cross-section that is orthogonal to the cutting edge (5), the difference between the narrow angle formed by the axis line (O) and the line tying the center (C) to the position on the cutting edge (5) where the depth of the gash (4) is maximal and the narrow angle formed by the axis line (O) and the line tying the center (C) to the position on the cutting edge (5) where the rake angle of the cutting edge (5) in the cross-section orthogonal to the cutting edge (5) is maximal on the positive angle side is within ±7°.</p> |
