Patent ID: 6093128
Filing Date: 2000-07-25
Classification: B25B,F16H

Abstract:
A self-shifting transmission for a ratchet wrench, comprising:a rotational drive means and a rotational output spindle means;a ratchet means driven by said output spindle means;a first transmission gear means and an overrunning clutch means rotatably connected in series between said rotational drive means and said rotational output spindle means;a centrifugal clutch means rotatably connected in parallel with said first transmission gear and said overrunning clutch drive means and said rotational output spindle means, said centrifugal clutch means rotatably connected to a shaft means which rotates in said overrunning clutch means such thatupon said drive means rotating at and above a predetermined rotational speed, said centrifugal clutch means engages to rotate said output spindle means while rotating said shaft means to overrun within said overrunning clutch; andupon said drive means rotating below said predetermined rotational speed, said centrifugal clutch means disengages thereby permitting said overrunning clutch to engage said shaft means and rotate said output spindle means through said first transmission gear means.