| 摘要 |
This invention relates to pneumatic tires having a sidewall which contains at least one internal annular rubber insert. In particular, this invention relates to pneumatic tires which rely upon internal pneumatic air pressure and to pneumatic tires which conventionally rely upon internal pneumatic air pressure but which have a capability of running for extended distances without any significant internal air pressure, namely ambient atmospheric air pressure, depending somewhat upon the positioning and configuration of the sidewall insert. At least one of said rubber sidewall inserts is composed of two segments, namely a radially inner rubber segment and a radially outer rubber segment. The inner rubber segment and outer rubber segment have significantly different modulus and hardness physical properties. A portion of the segments overlap each other. In one aspect, each of the segments of the dual segment sidewall insert may be comprised of various types of rubber compositions containing, for example, a dispersion of an ultra high molecular weight polyethylene and/or a dispersion of a starch/plasticizer composite and/or mixtures of carbon black and silica and/or any reinforcing and non-reinforcing materials that could be used to tune the gradient of stiffness. |
