Patent ID: 7753816

Claim:
A transmission system comprising: a transmission case; a compound planetary gear train, comprising a first planetary gear train having a plurality of planetary gear train members and a second planetary gear train having a plurality of planetary gear train members; said first planetary gear train comprising a sun gear, a ring gear and a plurality of planet gears operationally engaging both said sun gear and said ring gear and operationally connected to a first planet carrier; said second planetary gear train comprising a sun gear, a ring gear and a plurality of planet gears operationally engaging both said sun gear and said ring gear and operationally connected to a second planet carrier; said ring gear of said first planetary gear train conjoined to said ring gear of said second planetary gear train and said first planet carrier conjoined to said sun gear of second planetary gear train; a first prime mover having a first drive shaft operationally connected to said sun gear of said first planetary gear train and in power communication with an energy storage device, operable to transfer power between said energy storage device and said first drive shaft; a second prime mover having a second drive shaft selectively operatively connectable to an auxiliary driving mechanism which is operatively connected to said second planet carrier, the conjoining of members of said first planetary gear train and members of said second planetary gear train and the positioning of said first prime mover and said second prime mover ensuring that the re-circulating power does not exceed the input power; an output shaft operatively connected to said first planet carrier and said sun gear of said second planetary gear train; a first torque transfer device positioned to selectively operatively connect said second drive shaft to said auxiliary driving mechanism; a second torque transfer device positioned to selectively operatively connect said ring gear of said first planetary gear train to said sun gear of said first planetary gear train; a third torque transfer device positioned to selectively operatively connect said ring gear of said first planetary gear train and said ring gear of said second planetary gear train to said transmission case; and a fourth torque transfer device positioned to selectively operatively connect said sun gear of said first planetary gear train to said transmission case.