Patent ID: 7326141

Claim:
A transmission drive system for a differential speed steered vehicle, the system comprising: first and second AC induction traction motors, each operatively coupled to first and second semi-independent coaxial traction shafts, respectively; first and second AC induction steer motors coaxially mounted on a common steer axis parallel to the coaxial traction shafts; and a steering gear assembly comprising: a common steer input shaft operatively connected to the two AC induction steering motors; first and second planetary gear sets, the first and second traction shafts being operatively connected with one of a first and second planet gear carrier, or a first and second ring gear, respectively, of the first and second planetary gear sets, the other of the first and second planet gear carriers or the first and second ring gears being operatively connected with each other; first and second offset gears mounted to the steer input shaft and meshing with a first and second sun gear, respectively, of the first and second planetary gear sets; and a reversing idler gear interposed between one of the first and second offset gears and one of the first and second sun gears.