| 摘要 |
PROBLEM TO BE SOLVED: To prevent the occurrence of an unshaven part in a machinable material, by avoiding the fact that a cutting edge is not formed in an axial peripheral area of a distal end part, while improving the cutting quality by arranging bottom blades downward to a core. SOLUTION: This end mill is provided by forming at least a pair of bottom blades 8 extending to the outer peripheral side from the axis O side in this distal end part in the distal end part of an end mill body 1 rotated around the axis O. Among this, a pair of bottom blades 8A have a positive radial directional rake angle in an outer peripheral side area more than a peripheral area A of the axis O, and are connected via a chisel part 10 when mutual distal end flanks 9 cross by extending toward the axis O side in the peripheral area A of the axis O. COPYRIGHT: (C)2011,JPO&INPIT |
