Patent ID: 8118702

Claim:
A hand-held power nut runner, comprising: a housing with a rotation motor, an output shaft, and a reduction gearing connecting the motor to the output shaft; wherein the reduction gearing comprises a plurality of planetary gearing stages having a common ring gear supported in the housing, and each one of the planetary gearing stages includes a sun gear, a planet wheel carrier, and a plurality of planet wheel units engaging the ring gear and the sun gear; wherein each of the planet wheel units of at least one of the planetary gearing stages comprises two axially spaced spur gears fitted to a common spindle that is rotatively journalled relative to the planet wheel carrier via a needle bearing; and wherein one of the two axially spaced spur gears is rigidly secured to the common spindle, and the other one of the two axially spaced spur gears is supported on the common spindle via a wringing fit for self alignment with the rigidly secured spur gear, thereby evenly sharing a load between the two axially spaced spur gears.