| 摘要 |
The invention relates to a solid drill bit for machine tools. The solid drill bit has a drill bit body ( 10 ) and two indexable inserts ( 20, 22 ) which are arranged at a radial distance from one another in a respective insert seat ( 16, 18 ) of the drill bit body ( 10 ) in the region of a chip flute ( 12, 14 ). The indexable inserts ( 20, 22 ) have an essentially quadratic contour. They project with their front-end main cutting edges ( 30, 34 ) axially beyond the drill bit body ( 10 ) and overlap one another radially in their active region. The radially outer indexable insert ( 22 ), with its outer insert corner ( 36 ) and with its adjoining secondary cutting edges ( 38 ) perpendicular to the relevant main cutting edge ( 34 ), projects radially beyond the circumference of the drill bit body. In order to permit burr-free through-drilling, the front-end main cutting edge ( 34 ) of the outer insert ( 22 ) is subdivided in its longitudinal extent into a radially inner working section ( 50 ) and a rectilinear peeling section ( 52 ) adjoining said working section ( 50 ) on the outside and extending up to the outer insert corner ( 36 ), said sections ( 50 and 52 ) enclosing a setting angle of 95° to 120° with one another. In the fitted state, the peeling section ( 52 ), toward the outer insert corner ( 36 ), is accordingly set at a positive setting angle of 72° to 87° relative to the end face of the drill bit body.
|
