Patent ID: 6843293

Claim:
A pneumatic radial ply runflat tire having a tread, a carcass including a radial ply structure and two sidewalls each being reinforced by at least one reinforcing wedge inserts, the tire characterized by: the at least one reinforcing wedge insert being constructed of two or more different materials providing a structural moment of inertia that increases with increased strain in the sidewalls; characterized in that the least one reinforcing wedge insert in each sidewall, respectively, comprises a plurality of radially-layered, circumferentially disposed regions of a first flexible, low-hysteresis material separated by one or more circumferentially disposed layers of a second material being stiffer than the first material; in which the radially-layered, circumferentially disposed regions of flexible, low-hysteresis material and the layers of a second stiffer material are both triangularly shaped in cross section.