Patent ID: 7210878

Claim:
A core drilling machine with an electrical motor ( 2 ) for rotational drive of a core drilling bit ( 3 ) having cutting edges oriented axial to a work piece ( 4 ), a feeding means ( 6 ) for generation of the feed of the core drill bit ( 3 ) against the work piece ( 4 ) and a controller ( 7 ) for controlling, relative to a first one-to-one control parameter, detected by a sensor ( 8 , 8 ′) for one of electrical power consumption (P) and torque (M), wherein a force sensor ( 9 , 9 ′) is connected to the controller ( 7 ) for detecting a contact pressing force (F N ) of the core drill bit ( 3 ) as the second control parameter; wherein the force sensor ( 9 ′) is a power sensor of the feeding means ( 6 ); wherein the controller ( 7 ) is a microcontroller; and wherein the controller ( 7 ) is connected to an input means ( 14 ) for the radius (r) of the drill bit ( 3 ), with a transponder that queries an identification means ( 15 ) on the core drill bit ( 3 ).