| 摘要 |
<P>PROBLEM TO BE SOLVED: To provide an end mill capable of controlling generation of burrs and folding-backs of upper and lower surfaces of a work material (formed of fiber reinforced plastic), and obtaining a vertical cut surface. <P>SOLUTION: In the end mill 1, a main groove 3 is formed in a spiral shape from a bottom blade 2 side to a shank 8 side, a sub groove 7 in the direction opposite to the twisting direction of the main groove 3 is formed in a land part 6 of a main cutting blade 5 formed along the main groove 3, and a flank 10 orthogonal to the sub groove 7 is formed in a sub cutting blade 9 formed by the sub groove 7. The sub groove 7 can be formed toward the shank 8 side from the position separate from the bottom blade 2. Further, the number of the main grooves 3 is ≥3 and ≤5, and the number of the sub grooves 7 can be twice the number of the main grooves 3. <P>COPYRIGHT: (C)2013,JPO&INPIT |
