摘要 |
The drill chuck comprises a chuck body connected to a drive shaft of a drilling drive device so as to deliver hammer blows to the working tool (e.g. the drill) of a hammer drill and the like, a plurality of clamp jaws which axially guide and hold the drill bit centered on the chuck axis, and a catch device which optionally acts to restrain the drill bit from rotary slipping with respect to the chuck body. The chuck jaws are positioned to axially overlap any axially extending working grooves provided in the drill bit shaft. At least one catch device is provided circumferentially between the clamp jaws, is radially movable in the chuck body and is constructed to engage in grooves running axially in the drill bit shaft or not according to the desire of the operator without loosening during drilling. |