Patent ID: 7934440

Claim:
A powered wrench, comprising: a housing having a handle part, a gear part, an interior space, and a means for accessing the interior space, the gear part having a bore therethrough; a shaft rotatably mounted in the interior space of the handle part having a proximal end, a distal end, and a first axis of rotation, the distal end connected to a motor drive, the proximal end forming a worm gear extending into the gear part; a first spur gear in the interior space of the gear part having a first number of teeth defining a first gear ratio appropriate for the application of power joined in a gear stack with a second spur gear having a second number of teeth defining a second gear ratio appropriate for the application of speed, the worm gear selectively engaged through a means for moveably connecting with one of the first or second spur gears, the gear stack having a second axis of rotation extending through the bore perpendicular to the first axis of rotation, the gear stack translatable along the second axis of rotation from a first position where one of the first or second spur gears is engaged to a second position where the other spur gear is engaged; a means for shifting between the first position and the second position; and a means for engaging a work piece connected to the gear stack; whereby torque supplied by the motor and transmitted through the worm gear, the means for connecting, and the gear stack is applied to the work piece at a preferred speed governed by a selected gear ratio.