Patent ID: 7201235

Claim:
A driver drill comprising: a housing having a spindle protruding forward; a motor housed in the housing; a planetary gear reduction mechanism housed in a gear case of the housing for transferring output of the motor to the spindle and allowing an internal gear provided in front of the spindle to be rotatable; an engaging member held in the gear case for engaging with an end face of the internal gear; a pressing means that presses the engaging member from the front through an intermediate member held movably in the axial direction by the gear case; an interfering unit provided in the gear case for interfering with the intermediate member at a predetermined rotating position thereof to regulate movement of the intermediate member in the axial direction, and an operating member capable of rotating the intermediate member by rotative operation, wherein by rotative operation of the operating member, the intermediate member is rotated to a lock position where interference occurs with the interference unit and to a lock-releasing position where no interference occurs with the interference unit, thereby at the lock position a drill mode can be selected for regulating the movement of the intermediate member and prohibiting the internal gear from idling, and at the lock-releasing position a clutch mode can be selected for releasing the regulation of the movement of the intermediate member and allowing the internal gear to idle.