Abstract: An apparatus includes: a first shaft coupled to second and third shafts; a fourth shaft coupled to fifth and sixth shafts; a first differential coupled to the second and fifth shafts; a second differential coupled to the third and sixth shafts; a seventh shaft coupled to the first differential; an eighth shaft coupled to the second differential; a first torque and/or speed converter coupled to the seventh shaft; a second torque and/or speed converter coupled to the eighth shaft; a ninth shaft coupled to the first torque and/or speed converter; a tenth shaft coupled to the second torque and/or speed converter; an eleventh shaft coupled to the ninth and tenth shafts; a one-way bearing/coupling-uncoupling device coupled to at least one of the fourth, fifth, sixth, seventh, and ninth shafts; and an other one-way bearing/coupling-uncoupling device coupled to at least one of the fourth, sixth, eighth, and tenth shafts.

Abstract: A rotational power transmission apparatus is provided including an input coupler having first and second input shafts, a differential engine coupled to the first input shaft and transmitting power to a first output shaft. First and second one-way bearings are coupled to the first output shaft. A first torque converter is coupled to the first one-way bearing, and a second torque converter coupled to the second one-way bearing. An output coupler is coupled to output from the first torque converter, output from the second torque converter and a second output shaft.

Abstract: A rotational power transmission apparatus is provided including an input coupler having first and second input shafts, a differential engine coupled to the first input shaft and transmitting power to a first output shaft. First and second one-way bearings are coupled to the first output shaft. A first torque converter is coupled to the first one-way bearing, and a second torque converter coupled to the second one-way bearing. An output coupler is coupled to output from the first torque converter, output from the second torque converter and a second output shaft.

Abstract: The differential engine comprises a motor, a torque conversion stage, and a loading mechanism. The torque conversion stage includes first and second differential stages which are coupled together with a pair of shafts, with the shafts rotating in opposite directions. The first differential stage comprises an input shaft which is coupled to the output shaft of the motor, and first and second output shafts which are coupled to the respective shafts. The second differential stage comprises an output coupled to the output drive shaft, and first and second input shafts which are coupled to the respective shafts. The second differential stage includes a gear mechanism which applies a rotational torque to the output drive shaft when a difference occurs between the rotational speeds for the shafts. The rotational speeds of the shafts are varied by loading one or both of the shafts.