| 摘要 |
PROBLEM TO BE SOLVED: To prevent damage to a corner blade and deterioration of machined surface roughness due to a change in cutting edge strength of the corner blade or cutting load variations. SOLUTION: The distal end outer peripheral side of a wall surface facing in a direction of rotation T of an end mill in a chip discharge groove 4 of the distal end outer periphery of an end mill body 1 rotated around an axis O is taken to be a corner blade rake face 11. The corner blade 12 whose rotational track around the axis O forms a projected circular arc shape projected toward the distal end outer peripheral side is formed at the ridge portion of the corner blade rake face. A gash 7 is formed on the inner peripheral side of the corner blade rake face 11, and a wall surface facing in the direction of rotation T of the end mill is taken as a bottom blade rake face 8. A bottom blade 9 being continuous with the corner blade 12 and extended toward the inner peripheral side is formed at the ridge portion on the distal end of the bottom blade rake face. In an intersection line L between the corner blade rake face 11 and the bottom blade rake face 8, a distal end Q thereof is located radially inward with respect to the axis O than the center S of the projected circular arc formed by the corner blade 12 in the rotational track around the axis O, and extened from the rear end side in the direction of the axis O than a projected end P in the direction of the axis O of the corner blade 12. COPYRIGHT: (C)2010,JPO&INPIT |
