| 摘要 |
PROBLEM TO BE SOLVED: To provide a drill head capable of lengthening tool life, and improving the machining accuracy, surface roughness and straightness of a work. SOLUTION: In this drill head, cutting blades 2, 3 are respectively brazed at least to the center side and the outer peripheral side of the tip face part of a head body 1, a guide pad 5 is brazed to the outer peripheral part of the tip face of the head body 1, in the outer periphery side cutting blade 3, a front cutting face 7 is provided with a chip breaker 10, and the outside surface of the outer periphery side cutting blade 3 is provided with a margin part 9. A side cutting face 11 is formed without a chamfer part on the tip side in the drill rotating direction of the margin part 9 in the outer periphery side cutting blade 3, a side cutting edge 12 is formed along the tip edge of the margin part 9, and the side cutting edge 12 is formed extending from the corner part K with a front cutting edge 6 to the total length of the leading edge of the margin part 9. COPYRIGHT: (C)2006,JPO&NCIPI
|
