A method of operating a power tool chuck assembly includes inserting a tool bit within a central bore of a chuck body, displacing a plurality of jaws with the tool bit from an extended position to a retracted position, displacing the jaws from the retracted position toward the extended position with a spring, rotating a tightening sleeve about a rotational axis in a tightening direction, thereby imparting an axial displacement to the tightening sleeve relative to the chuck body, inwardly displacing a plurality of clamping nuts in a radial direction in response to engagement between a wedge defined on the tightening sleeve and the clamping nuts, causing respective threads on the clamping nuts and the jaws to engage, and applying a clamping force on the tool bit with the jaws in response to continued rotation of the tightening sleeve in the tightening direction.

A jaw for use in a drill chuck having a longitudinal center axis, comprising a chuck body which includes a jaw face formed on an inner surface of the chuck body and a plurality of teeth formed on an outer surface of the chuck body, the jaw face being substantially parallel to the longitudinal center axis. A ridge depends inwardly from the jaw face toward the longitudinal center axis. The ridge includes a tool engaging surface that is substantially parallel to the longitudinal center axis and has a width of between 0.020 to 0.060 inches.

A chuck assembly, for use with a rotary power tool, includes a chuck body rotatable about an axis, a plurality of jaws supported by the chuck body for relative movement therewith between a retracted position for permitting insertion of a tool bit within the chuck body and an extended position for clamping the tool bit, a plurality of clamping nuts surrounding the chuck body and having interior threads engageable with corresponding threads on the respective jaws, a tightening sleeve surrounding and threadably engaged with the chuck body for relative rotation therewith, and a wedge defined on the tightening sleeve for selective engagement with the clamping nuts for inwardly displacing the clamping nuts, causing the respective threads on the clamping nuts and jaws to engage, in response to rotation of the tightening sleeve relative to the chuck body in a tightening direction.

A chuck device in which a rotary sleeve provided to a main body is rotated, and by rotation of an annular rotary body which rotates together with the rotary sleeve, jaws screwed together with the rotary body are expanded, contracted, advanced, and retracted, and a tool is gripped by the jaws; the chuck device comprising a retaining engaging body for engaging with the rotary body and preventing the rotary sleeve from coming out of the rotary body; wherein the retaining engaging body is provided to be fixed to a proximal end side of the rotary sleeve; a rotation transmission part for directly or indirectly transmitting the rotation of the rotary sleeve to the rotary body is provided to the retaining engaging body; and the rotation of the rotary sleeve is transmitted to the rotary body via the retaining engaging body, and the rotary body rotates together with the rotary sleeve.