Locking chuck

A chuck for use with a manual or powered driver having a rotatable drive shaft, said chuck comprising:

• a generally cylindrical body having a nose section and a tail section, said nose section having an axial bore formed therein;
• a plurality of jaws movably disposed with respect to said body in communication with said axial bore;
• an annular nut having threads formed thereon in engagement with threads on said jaws so that rotation of said nut about said body moves said jaws toward or away from said axis;
• a sleeve having a first portion comprised of a polymer, said sleeve being rotatably mounted about said body so that rotation of said sleeve in a closing direction moves said jaws toward a longitudinal axis of said axial bore and rotation of said sleeve in an opening direction moves said jaws away from said longitudinal axis;
• a bearing having a first race adjacent said body, a second race adjacent said sleeve and at least one bearing element disposed between said first race and said second race, one of said first race and said second race defining a ratchet and the other of said first race and said second race defining a pawl;
• and
• a ring comprised of metal and defining a cam surface that is configured to selectively engage said pawl, said ring being non-rotatably fixed to an inner surface of said first portion of said sleeve and disposed radially outward of said nut such that said pawl is disposed radially inward of said ring,
• wherein said ratchet and said pawl are configured so that when said pawl engages said ratchet, said ratchet and pawl prevent said second race from rotating in said opening direction with respect to said first race, and
• wherein said first portion of said sleeve is disposed radially outward of said ring and entirely encloses said ring in the radially outward direction.