Patent ID: 7334850

Claim:
A traction system for a vehicle, comprising: a support frame defining a substantially circular track belt support that is revolvable about an axis at a center of said track belt support, said axis being in a fixed position with respect to a chassis of the vehicle; a flexible track belt and a track belt stretching assembly for lengthwise stretching of said flexible track belt comprising one or more telescoping track belt stretching rollers; said system having a first traction configuration in which the flexible traction belt is held on said support frame to form a substantially circular, wheel-like traction surface, said belt stretching assembly can change to a belt stretching state in which said rollers engage said belt and stretch the track belt out from a relatively relaxed state in said first traction configuration, to a stretched state defining one or more other traction configurations of the system; and wherein said support frame comprises two coaxial circular cooperating support members with a gap between them defining together said circular track belt support, said gap extending radially from the axis to the lateral part of said gap defining a track belt stretching assembly-holding space, said belt-stretching assembly being housed within said space in said first traction configuration.