Quick release chuck device

A quick-change chuck device, comprising:

• a body member having a recess defined therein for receipt of a circular tool shank, said body member further comprising a plurality of tapered slots defined therein in communication with said recess, each said tapered slot being tapered in the longitudinal direction and further defining a longitudinally extending opening into said recess;
• an outer sleeve member coaxial about said body member and axially movable relative to said body member, said body member further comprising a plurality of inner diameter pin engaging surfaces;
• an axial spring mechanism disposed relative to said sleeve member and said body member so as to bias said sleeve member longitudinally relative to said body member to a biased position, said sleeve member axially movable against the biasing force of said spring mechanism to a released position;
• a plurality of tapered pins, each said tapered pin seated within a different one of said tapered slots, each said longitudinally extending opening in each said slot having dimensions such that a portion of each said tapered pin extends into said recess along the entire length of said pin defining a line contact between each said pin and a tool shank inserted into recess in said biased position of said outer sleeve member;
• and
• each said outer sleeve pin engaging surface being tapered to such a degree so as force one of said tapered pins uniformly radially inward upon said outer sleeve moving to said biased position such that said portion of each said pin defining said line contact moves essentially parallel to a centerline axis through said recess.

A machine tool configured for driving a tool bit, said machine tool comprising:

• a drivable spindle
• a quick-change chuck device, said chuck device further comprising:
• a body member having a recess defined therein for receipt of a circular tool shank, said body member further comprising at least one tapered slot defined therein in communication with said recess;
• an outer sleeve member coaxial about said body member and axially movable relative to said body member, said outer sleeve member further comprising at least one inner diameter pin engaging surface;
• an axial spring mechanism disposed relative to said sleeve member and said body member so as to bias said sleeve member longitudinally relative to said body member to a biased position, said sleeve member axially movable against the biasing force of said spring mechanism to a released position;
• and
• at least one tapered pin seated within said at least one tapered slot, said at least one tapered pin contacting said at least one outer sleeve pin engaging surface and thereby being forced radially inward within said slot so as to extend into said recess in said biased position of said outer sleeve, said pin being movable radially outward within said slot in said released position of said outer sleeve.