Drill
AssigneeSumitomo Electric Hardmetal Corp.
InventorsYuma Kawakami, Daisuke Murakami, Masaaki Jindai, Keiji Kinoshita
Life of this patent
Estimating the term…
Abstract
Provided is a drill having a flat-shaped drill tip and excellent in cutting edge strength and chip removability. The drill includes: a cutting edge extending in a direction at an angle α of not less than 85° and not more than 90° with respect to a drill axis (line O-O); a flank face contiguous to the cutting edge and having a clearance angle β of not less than 5° and not more than 10° with respect to the drill axis (line O-O); and a rake face located opposite to the flank face across the cutting edge, the cutting edge includes a recess receding in a direction parallel to the drill axis (line O-O), and the rake face includes a front clearance formed at a side of an outer periphery of the drill.
Claims4
A drill comprising:
- a cutting edge extending in a direction at an angle of not less than 85° and not more than 90° with respect to a drill axis;
- a flank face contiguous to the cutting edge and having a clearance angle of not less than 5° and not more than 10° with respect to a perpendicular to the drill axis;
- and
- a rake face located opposite to the flank face across the cutting edge,
- the cutting edge including a recess receding in a direction parallel to the drill axis,
- the rake face including a front clearance formed at a side of an outer periphery of the drill,
- the recess receding from the top of the cutting edge and forming an arc shape as the drill is seen sideways, wherein
- the rake face includes a thinning portion formed at a side of the drill axis,
- the thinning portion includes a linear portion and a curved portion as seen from above a tip of the drill, the linear portion is shaped to extend beyond the drill axis, and an outer end of the curved portion is located inside the outer periphery of the drill.
Dependencies are inferred from the claim text.