Patent ID: 7308948

Claim:
An electric power tool comprising: a housing; a motor; a planetary gear reduction mechanism which transmits output of the motor to an output shaft protruding from a front side of the housing and rotates an internal gear; a pressing means for pressing and fixing the internal gear; an impact mechanism which applies an intermittent impact to the output shaft in a rotative direction; a releasing means which selectively releases the impact to the output shaft applied by the impact mechanism; a clutch switching member which is slidable between a first sliding position to engage with the internal gear so as to regulate the rotation of the internal gear and a second sliding position to disengage from the internal gear so as to release the regulation of the rotation of the internal gear; an impact switching member which is slidable between a first sliding position to release impact by the impact mechanism with the operation of the releasing means and a second sliding position to apply impact by the impact mechanism without the operation of the releasing means, and a common switching member which simultaneously engages with both the clutch switching member and the impact switching member to slide them when the common switching member is moved to a predetermined position, whereby combination of the above sliding positions is changeable, wherein by moving the common switching member located outside of the housing, one operation mode is selectable among the following: an impact mode where impact is applied by the impact mechanism and internal gear rotation is regulated simultaneously; a clutch mode where impact by the impact mechanism is released and the regulation of the internal gear rotation is released simultaneously, and a drill mode where impact by the impact mechanism is released and the internal gear rotation is regulated simultaneously.