Patent ID: 8894073

Claim:
A drill chuck having a rotatable drive shaft, comprising: a generally cylindrical body having a nose section and a tail section, the tail section being configured to rotate with the drive shaft and the nose section having an axial bore formed therein; a plurality of jaws movably disposed with respect to the body and in communication with the axial bore for securing a shank of a tool in the drill chuck, each jaw comprising: a body including a substantially planar jaw face formed on an inner surface of the body and a plurality of teeth formed on an outer surface of the body, the jaw face being both disposed in a first plane and parallel to a longitudinal center axis of the drill chuck; and a ridge depending inwardly from the first plane in which the jaw face lies toward the longitudinal center axis, the ridge including a substantially planar tool engaging surface that is disposed in a second plane and is parallel to both the jaw face and the longitudinal center axis, wherein the tool engaging surface is disposed closer to the longitudinal center axis than the jaw face and only the tool engaging surface engages the shank of the tool when the tool is secured in the chuck; a nut rotatably mounted about the body such that rotation of the nut in a closing direction moves the jaws toward the longitudinal center axis of the drill chuck and rotation of the nut in an opening direction moves the jaws away from the longitudinal center axis of the drill chuck; and a sleeve rotatably mounted about the body such that rotation of the sleeve in the closing direction moves the jaws toward the longitudinal center axis of the drill chuck and rotation of the sleeve in the opening direction moves the jaws away from the longitudinal center axis.