Abstract: A gear-reducing, torque-multiplying gear drive assembly includes a stationary outer case housing an internal rotary carrier having an output shaft fixed thereto which is journaled by the case for rotation of the carrier and shaft relative to the case. A pair of electric motors are mounted on the carrier and drive a pair of associated planet gears which are enmeshed with a fixed sun gear. Operating the motors rotates the planet gears causing the carrier and the output stub shafts fixed thereto to rotate about a common axis of the stub shafts.

Abstract: A gear-reducing, torque-multiplying gear drive assembly includes input and output shafts journaled by a case for rotation about a common first axis. A rotary cage is accommodated within the case and is fixed to the output shaft. A bevel drive gear is fixed on the input shaft. Input and output bevel gear sets are mounted on planet shafts carried by the cage in spaced, parallel relation to the input bevel gear. A set of transversely arranged idler bevel gears couple the drive gear to the input planet gears. The output planet gears are enmeshed with a stationary sun gear. Rotating the input shaft rotates the planet gears through the transverse idler bevel gears, which in turn rotates the cage and output shaft.

Abstract: A gear-reducing, torque-multiplying gear drive assembly having a housing journaling coaxial input and output shafts coupled by an orbital gear drive assembly. A driving sun gear is fixed on the input shaft and rotates a plurality of input planet gears fixed to associated planet shafts journaled at their opposite ends by end walls of a rotary cage within the housing. Each planetary shaft also has an output planet gear within the cage enmeshed with a stationary sun gear fixed to the housing. Rotating the input shaft rotates the planet gears which in turn rotates the cage and drives the output shaft. Selecting the output planetary gears and stationary sun gear to be twice the size of the input gears produces a 2:1 gear ratio between the input and output shaft with a resultant 1:4 torque ratio.