Patent ID: 6887018

Claim:
A chuck for an annular core bit ( 1 ) having an inner thread ( 2 ), comprising a motor-driven rotatable spindle ( 4 ) having a threaded support ( 5 ) cooperating with the inner thread ( 2 ) for supporting the annular core bit ( 1 ), and an axial stop flange ( 6 ); a stop member ( 7 ) associated with the axial stop flange ( 6 ), provided at a working tool side of the axial stop flange ( 6 ), axially connectable with the axial stop flange ( 6 ) under compressive strain, and axially displaceable relative thereto, within predetermined limits, for replaceably securing the annular core bit ( 1 ); displaceable, within predetermined limits, locking wedge means ( 9 ) for axially connecting the stop member ( 7 ) with the axial stop flange ( 6 ) under compressive strain; and a manually actuatable, displaceable release member ( 10 ) for displacing the locking wedge means ( 9 ) between a position in which the locking wedge means ( 9 ) axially connects the stop member ( 7 ) and the axial stop flange ( 6 ) under compressive strain, and a position in which the stop member ( 7 ) is axially displaceable relative to the axial stop flange ( 6 ).