Tyres with a soft rubber rib on the bead rim - to maintain a sliding seal against the wheel rim

摘要

The base of the rim of a car tyre carcass is provided with an annular rubber rib having a radiused crest which is elastically compressible to seal the seat between the tyre and the wheel. The rib may be alongside the outer edge of the rim or radially beneath the bead reinforcement hoops. The rib is pref. made of rubber of 70-98 degrees Shore A hardness and has a base width/depth ratio of between 2 and 3. The rib section may have a trapezoidal, triangular or arcuate cross-section. The rib inhibits of pressure if the rim is displaced on the wheel rim by transient stresses, e.g. cornering with a tyre running at too low a pressure to prevent the tyre from shifting.