Patent ID: 7824289

Claim:
A differential steering-drive for a vehicle having respective left and right driving traction elements, a propulsion engine with an engine drive shaft, and a steering wheel rotatable by an operator to indicate an intended direction of travel, said steering-drive comprising: a drive differential interconnecting said engine drive shaft and a pair of respective track drive shafts for differentially driving said respective left and right driving traction elements; and a steering differential operatively interconnecting said steering wheel and said respective track drive shafts so that: rotation of said steering wheel in a first direction causes rotation of said steering differential in a first direction and rotation of said steering wheel in an opposite direction causes rotation of said steering differential in an opposite, the speed of rotation of said steering differential in each direction being proportional to the angular rotation of said steering wheel; and the rotation of said steering differential in said first direction results in the rotation of said respective track drive shafts in opposite directions; and wherein said differential steering-drive further comprises one of the following combinations: (a) at least one of said drive and steering differentials comprises an all-gear limited-slip differential; and (b) said drive differential and said steering differential each comprise an all-gear limited-slip differential.