Drill bit, has main cutting edge divided into two partial cutting edges, where one of edges is designed as free cutting edge with clearance angle opposite to free cutting edge-accessory end flank which is attached with free edge

摘要

The bit (1) has a main cutting edge divided into two partial cutting edges, where one of the edges is designed as a guiding cutting edge (5) with a guiding bevel. The guiding edge has a supporting bevel (14) that is provided at a guiding cutting edge-accessory end flank (11) such that the bevels limit the guiding flank in a rotating direction of the bit. The guiding flank is attached to the guiding edge. The other edge is designed as a free cutting edge (6) with a clearance angle opposite to a free cutting edge-accessory end flank which is attached with the free edge.