Patent ID: 7387054

Claim:
A device for driving screws comprising: a shank having an end portion defined by a wall of annular cross-section defining a seat, said end portion terminating at an end surface, a plurality of radial bores formed in said wall; a screw bit having a head end received in said seat and a driver end adapted to drive a screw; a sleeve surrounding at least part of said end portion of said shank and axially movable, relative to said shank, said sleeve having a surface facing said shank with a plurality of recesses, said sleeve having a bottom surface with an aperture through which said screwdriver bit is disposed; a spring disposed between said end portion of said shank and said bottom of said sleeve to provide a biasing force between said shank and said sleeve, wherein said spring is disposed between said end surface of said shank and said bottom portion of said sleeve; and a plurality of balls disposed in respective bores in said end portion of said shank, said balls held in engagement with said screw bit head when said balls are in contact with a non-recess portion of said sleeve, said balls movable in a radial direction away from said screwdriver bit head into said recesses when said balls align with said recess, thereby disengaging contact with said screw bit head.