| 摘要 |
In order to make a vehicle tyre relatively flat-proof, a flexible, pressurised, closed-cell, syntactic foam tyre insert is fitted within the tyre to extend over the tread and adjoining sidewall areas. The tyre insert comprises a plurality of preformed elastomeric spheres compressed and moulded together into the configuration of the interior of the tyre casing, or a segment thereof. Each such elastomeric sphere is pressure moulded from a castable plastic resin in a mould (24) to form a hollow, thin-walled, seamless, pressurised, elastomeric sphere. The elastomeric spheres are coated with a liquid resin to fill any voids between said elastomeric spheres after they are compressed, and to bond said elastomeric spheres together when cured. The pressurised elastomeric spheres are manufactured in an apparatus which simultaneously rotates the mould (24), having a spherical mould cavity 24c, about two perpendicular axes of said cavity 24c to provide a uniform, thin-walled sphere. |
