Patent ID: 7326009

Claim:
A drill body for chip-removing metal machining defining a center axis of rotation, the drill body comprising: a front head and a rearwardly extending hollow shaft adapted for connection with a tube, the front head being configured symmetrically about the center axis of rotation and including a bridge defining a plurality of chip inlet openings in the front head, the bridge including a first material; an axial through-channel adapted to internally evacuate metal chips, the axial through-channel extending between the plurality of chip inlet openings in the front head and an outlet opening at a rear end of the hollow shaft; and a plurality of cutting edges being located behind the inlet openings respectively with reference to a direction of rotation of the drill body, each cutting edge including a second material integrally sintered with the first material of the bridge, and the pluralities of cutting edges and chip inlet openings being configured symmetrically with respect to a tip disposed along the center axis of rotation, each cutting edge extending between the tip and a periphery of the front head and including: a chip surface facing a respective chip inlet opening; and a clearance surface extending rearwardly from the chip surface with reference to the direction of rotation of the drill body.