Abstract:
An automatic torque transmission with one or more stages, where each stage has a number of available gear ratios. There is a planetary gear train comprising a planet gear on a planet gear carrier, a sun gear, and a ring gear, wherein an input to the planetary gear train is through the planet gear carrier, and wherein the planet gear is configured to drive the sun gear at higher speed and lower torque, and the ring gear at lower speed and higher torque. There is a first differential gear train having a first input side, a second input side, and an output, wherein the sun gear is coupled to the first input side of the first differential gear train and the ring gear is coupled to the second input side of the first differential gear train, thereby combining two inputs into a single output. A brake clutch is configured to be selectively coupled to the ring gear, to provide selective braking of the ring gear so as to selectively transfer drive from the ring gear to the sun gear. A one-way clutch is configured to be selectively engaged or disengaged from the sun gear, to selectively prevent rotation of the sun gear in one direction. The output of the differential gear train is coupled to either another stage of the transmission or to an output differential gear train. The output differential gear train is configured to be locked for forward drive or coupled to a housing for reverse drive. With the one-way clutch disengaged the sun gear will freewheel by rotating in reverse, with no output.