A chuck for use with a manual or powered driver having a housing and a
rotatable drive shaft extending therefrom is provided. The chuck includes
a generally cylindrical body member having a nose section and a tail
section. Each of a plurality of jaws is slidably positioned in one of a
plurality of angularly disposed passageways in the body. Each jaw has a
jaw face formed on one side thereof and threads formed on the opposite
side thereof. A nut is rotatably mounted on the body in engagement with
the jaw threads so that rotation of the nut moves the jaws axially within
the passageways. A locking member, in a first axial position, is
rotatable with respect to the driver housing. In a second axial position,
it operatively engages the housing and the nut so that the locking member
is rotationally held to the housing and the nut so that the nut is
rotationally held to the housing. The locking member is axially
reciprocal between the first axial position and the second axial
position.