BOHRVORRICHTUNG ZUR HERSTELLUNG VON BOHRLÖCHERN MIT HINTERSCHNEIDUNG.

摘要

A drilling device for producing drilled holes with an undercut has a drill bit having a drilling head, a depth stop, an enlargement provided between the the drilling head and the depth stop and acting as a swivel bearing, a suction bell rotatably mounted on the depth stop, a bearing washer, and a resilient, ring-shaped cushioning element provided on the depth stop. The cushioning element abuts against the bearing washer and is connected to the suction bell. The depth stop of the drill shank has a concavely curved end face and the bearing washer has a convexly curved sliding face which rests on the concavely curved end face of the depth stop.