Drilling machine, in particular hand-held core drilling machine

摘要

The machine (10) has a drive including a motor for driving a tool spindle and two transmission stages, and a centering retainer retaining a pilot drill bit (24). A tool retainer (14) retains a drill bit (18), where the drill bit and the pilot drill bit are arranged concentrically with one another. The pilot drill bit drills a pilot hole, where one of the transmission stages is more drivable in a rotational speed range through the pilot hole. The drill bit drills a core hole, where the other transmission stage is more drivable in another rotational speed range through the core hole.