US Patent 7216873 Drill chuck

A drill chuck has a chuck body centered on and axis, and a tightening element surrounding the body and rotatable thereon about the axis. The tightening element has a front sleeve formed with jaw-holding guides and a rear sleeve releasably coupled with the front sleeve. A retaining ring bears axially forward on the sleeve. Releasable locking formations on the ring and body are relatively displaceable between a retaining position preventing axial rearward shifting of the ring and sleeve on the body and a freeing position permitting such shifting. A pusher rotationally coupled to the jaws bears axially forward on the jaws. Interengaging screwthreads on the pusher and chuck body are provided so that relative rotation of the sleeve together with the jaws and pusher relative to the chuck body axially displaces the jaws between their positions.