| 摘要 |
<p>In the radius end mill of the present invention, main gash faces (17) whose angle of inclination with respect to an axis (O) is smaller than a twist angle (±) of chip discharge flutes (12) are formed on inner circumferential sides of distal end portions of wall surfaces (13) that face in a tool rotation direction of helically twisted chip discharge flutes (12) formed on an outer circumference of a distal end portion of a tool body (11) that is rotated around an axis (O), and end cutting edges (15) are formed on a distal end of the main gash faces (17), and sub gash faces (18) whose angle (²) of inclination with respect to the axis (O) is greater than that of the main gash faces (17) are formed on an outer circumferential side of the main gash faces (17) such that they extend away via step portions (19) from the main gash faces (17). In addition, corner cutting edges (16) that have a protruding arc-shaped contour are formed so as to be continuous with an outer circumferential side of the end cutting edges (15) extending from a distal end as far as an outer circumference of the sub gash faces (18).</p> |
