Patent ID: 6716380
Filing Date: 2004-04-06
Classification: B29C,B60C,Y10T

Abstract:
A process for expanding at least one partially cross-linked blank which is intended to form, in the cross-linked, expanded state, all or part of an elastomeric safety support of cellular structure having closed cells and reduced air permeability, said support being intended to be mounted on a wheel rim within a tire, comprising:curing said or each blank in a bath of liquid fluid at excess pressure which is contained in an enclosure, the temperature of said bath having a maximum value of between 110Â°C. and 210Â°C., said bath having an absolute pressure at least a value equal to or greater than 5 bar and a final pressure-relief value substantially equal to 1 bar, wherein said or each blank is capable of unlimited increases in volume with respect to said enclosure, wherein said elastomeric safety support comprises an intermediate layer located radially towards an inside of an outer surface of the elastomeric safety support, and a core having a density greater than the density of the intermediate layer, wherein said elastomeric safety support has a cross-section through said support and said intermediate layer has a thickness, wherein the cross-section has a smallest dimension, wherein said thickness is between 5% and 30% of the smallest dimension of a cross-section through said support or part thereof.