Patent ID: 6479008
Filing Date: 2002-11-12
Classification: B29D

Abstract:
A method of moulding and curing tires for vehicle wheels, comprising the following steps:disposing a tire on a toroidal support the outer surface of which substantially mates an inner surface of the tire; closing the tire and the toroidal support inside a moulding cavity defined in a vulcanization mould, said moulding cavity having walls the shape of which match that of an outer surface of the tire when vulcanization has been completed; pressing the outer surface of the tire against the moulding cavity walls; transmitting heat to the tire to cause a molecular cross-linking; wherein during said pressing step an expansion is imposed to the tire; wherein the tire expansion is carried out by admitting a fluid under pressure to at least one gap for fluid diffusion created between the outer surface of the toroidal support and the inner surface of the tire; wherein the admission of fluid under pressure takes place to an upper portion of the moulding cavity communicating with a lower portion of the cavity through said diffusion gap; drawing fluid under pressure out of the lower portion of the moulding cavity, carried out concurrently with said admission step, so as to create a pressurized fluid stream in the diffusion gap; and, an axial movement of the inner circumferential edges of the tire from the equatorial plane of the toroidal support carried out concurrently with the tire expansion.