Patent ID: 7828077

Claim:
A rotary tool for driving a fastener, said rotary tool comprising: a motor operable to provide a rotational force and having a rotational axis; a motor output shaft associated with said motor; a drive shaft rotatably driven by said motor via said motor output shaft, said motor output shaft and said drive shaft having substantially parallel axes of rotation, said drive shaft comprising a first gear at its end opposite said motor output shaft; a chuck assembly, said chuck assembly comprising a second gear and a chuck output shaft for rotatably driving a fastener, said chuck output shaft having a rotational axis that is non-parallel to the rotational axis of said drive shaft, wherein said chuck output shaft is adapted to rotate with said second gear and translate axially relative to said second gear; wherein said first gear imparts rotation to said second gear and said chuck output shaft to rotate said chuck output shaft about the rotational axis of said chuck output shaft when said motor is activated; a sensor responsive to at least one of (a) movement of said chuck output shaft relative to said second gear and said sensor and (b) proximity of said chuck output shaft to said sensor, and wherein said sensor generates an output signal indicative of said at least one of (a) movement of said chuck output shaft relative to second gear and said sensor and (b) proximity of said chuck output shaft to said sensor, and wherein said motor is responsive to said output signal; and wherein said sensor detects longitudinal movement of said chuck output shaft relative to said second gear whereby the power supplied to said motor is proportionally adjusted to variably alter the corresponding rotational speed of said chuck assembly in response to said detection of longitudinal movement of said chuck output shaft relative to said second gear.