Chuck for annular core bit

1. 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 ).

2. A chuck according to claim 1 , wherein the locking wedge means ( 9 ) is formed as annular wedge means tapering radially inwardly.

3. A chuck according to claim 1 ; wherein the release member ( 10 ) is formed as a manually rotatable, accessible from outside, stop ring having a guide profile ( 14 ) spaced from the locking wedge means ( 9 ) by two different distances corresponding to the two positions of the locking wedge means ( 9 ).

4. A chuck according to claim 1 , further comprising displaceable stop bodies ( 11 ) provided between the release member ( 10 ) and the locking wedge means ( 9 ).

5. A chuck according to claim 4 , further comprising spring means ( 15 ) for pre-loading the stop bodies ( 11 ) and for automatically axially displacing, via the locking wedge means ( 9 ), the stop member ( 7 ) away from the axial stop flange ( 6 ).

6. A chuck according to claim 1 , further comprising a snap ring ( 12 ) provided at a working tool side of the stop member ( 7 ) and securable to the work spindle ( 4 ) for limiting axial displacement of the stop member ( 7 ).

7. A chuck according to claim 1 , wherein the stop member ( 7 ) is formed as a deflection-resistant stop ring provided, on a working tool side thereof with an axial flange surface ( 8 ) and, on a power tool side thereof with an annular wedge surface ( 7 a ) formed as a result of a thickness thereof increasing radially inwardly.

8. A chuck according to claim 1 , wherein the axial stop flange ( 6 ) has, at a working tool side thereof, an annular wedge surface ( 6 a ) formed as a result of a stop flange thickness increasing radially inwardly.

9. A chuck according to claim 1 , further comprising annular sealing rings ( 13 ) provided, respectively, between the axial stop flange ( 6 ), the release member ( 10 ), and the stop member ( 7 ) and located in respective sealing grooves.