Patent ID: 8070168

Claim:
A drill chuck comprising: a chuck body centered on and rotatable about an axis; a holder body rotatable on the chuck body and formed with a plurality of angularly spaced guides; a tightening sleeve surrounding the bodies; respective jaws in the guides between the tightening sleeve and the chuck body; means for shifting the jaws in the guides forward and together on rotation of the holder body in a tightening direction relative to the chuck body and for opposite shifting of the jaws on rotation of the holder body relative to the chuck body in an opposite loosening direction; an annular array of teeth rotationally fixed to one of the bodies; a pawl angularly fixed on the other of the bodies and engageable with the teeth; a spring biasing the pawl into engagement with the teeth, the pawl and the array of teeth being oriented such that when the pawl is in a locking position engaged with the array of teeth the holder body can rotate relative to the chuck body in the tightening direction but not in the loosening direction and when in a freeing position disengaged from the teeth the holder body can rotate freely in either direction relative to the chuck body, the pawl and the spring being made in one piece; respective interengaging stops on the other body and on the tightening sleeve limiting relative angular movement of the tightening sleeve on the other body between a pair of angularly offset end positions; and a spring-loaded retainer having a pair of angularly offset seats engageable with the tightening sleeve and releasably holding the tightening sleeve relative to the other body in the end positions.