Patent ID: 7137920

Claim:
A vehicle having said at least two pairs of driving wheels wherein at least one of said pairs is steerable in relation to the longitudinal axis of said vehicle, said vehicle comprising: a first transmission branch; a second transmission branch; at least two control units, each comprising a planetary gear set and a control motor, said planetary gear set comprising a sun gear, an internal gear, and planet wheels; and a hub reduction gear, wherein said transmission branches are connected to one another by way of a fork and one of said transmission branches comprises a drive shaft, said control units disposed between said drive shaft and a driving wheel, said control motor interacting with said sun gear by way of a gear, said drive shaft interacting with said internal gear by way of a coaxial connection through said sun gear, said driving wheel interacting with said planet wheels, said control motor influencing the planetary gear-set to vary the transmission ratio of said second branch, said hub reduction gear disposed between said planet wheels and said driving wheel, and wherein each of a plurality of steerable wheels is connected to said drive shaft by way of one of said control units.