Patent ID: 8851581

Claim:
A traction system for a vehicle comprising: a) at least one fixed drive wheel, wherein said fixed drive wheel is attachable to a shaft of the vehicle; b) at least one mobile drive wheel, wherein said mobile drive wheel is attachable to a shaft of the vehicle; c) a main frame, wherein said frame comprises: i) a first circular aperture in which a rolling mechanism is installed; ii) a cavity comprising a plurality of second apertures to fix a pivotal member; d) a pivotal member, wherein said pivotal member is pivotally mounted: i) at a first extremity, to the at least one mobile drive wheel; ii) at the other extremity, to the cavity of the main frame allowing lateral movement in relation to the said cavity; e) at least one idler wheel pivotally mounted at each extremity of the main frame; f) a plurality of road wheels pivotally mounted to the main frame; g) a traction band installed around the drive wheels, the idler wheels and the road wheels; wherein the second apertures to fix the pivotal member are positioned on the frame to ensure that the mobile drive wheel applies a constant tension on the traction band during the pivotal movement of the mobile drive wheel induced by the variation of the angle between the pivotal member while pivoting around a rotation axis of said shaft.