Patent ID: 7455121

Claim:
A power tool comprising: a housing; a motor comprising an output shaft; and a speed reduction mechanism comprising: a pinion gear connected to the output shaft; a planetary gear disposed around the pinion gear and engaged with the pinion gear; a fixed gear surrounding the planetary gear and engaged with the planetary gear; a support member holding the fixed gear, said support member comprising: an outer surface held by the housing; an inner surface holding the fixed gear; a bearing disposed coaxially with the fixed gear; and a rotation stopper engaged with the housing thereby preventing the support member from rotating; and a spindle connected to the planetary gears and held by the bearing; a mechanism portion connected to the spindle and transmitting a rotational power of the speed reduction mechanism to an end tool; a first projection extending from a side surface of the fixed gear; and a first hole formed on the support member radially outward of the bearing and holding the first projection thereby limiting a rotation of the fixed gear, wherein the first projection, the first hole and the bearing are aligned in the radial direction of the bearing.