Patent ID: 7473058

Claim:
An electric power tool, comprising: a base assembly; a motor housing slidably mounted on the base assembly; a motor and transmission mechanism contained in the motor housing connected to an output shaft on which a bit is to be fixed; a vertical toothed bar mounted on one of the base assembly and the motor housing and a gear shaft horizontally mounted on the other of the base assembly and the motor housing; a first gear rotatably mounted on the gear shaft and being engaged with the toothed bar; a second gear mounted on the other of the base assembly and the motor housing and slidably movable between a first position and a second position; and a knob mounted on the other of the base assembly and the motor housing for operably rotating the second gear; wherein, when the second gear is at the first position, the second gear directly engages the first gear and, when the second gear is at the second position, the second gear disengages the first gear.