Membrane for secondary air suspension of a land or rail vehicle, method of manufacturing same, its suspension and vehicle incorporating same

A substantially toroidal membrane having an axial section substantially “Ω” shaped like a tire, the membrane comprising two attachment areas and at least one corded layer of at least one fabric thread extending from one of said attachment areas to the other one, said at least one corded layer being wound in adjacent turns radially on the outside of a radially internal elastomer layer and on the inside of a radially external elastomer layer which is deposited on the outside of said at least one corded layer,

• wherein said at least one fabric thread of said at least one corded layer is individually sheathed by an elastomer sheath which is extruded around said at least one fabric thread and which is compatible with said internal and external layers,
• and wherein the membrane is able to equip a secondary air suspension of a rail vehicle by being mounted under an auxiliary air tank under a body of the vehicle while communicating with said tank, the membrane being able to withstand operating pressures between 8 and 12 bars in said secondary air suspension,
• and wherein said attachment areas are respectively reinforced by two rods which consist of said at least one fabric thread circumferentially in extension of said at least one corded layer, these rods consisting of a textile cord forming said at least one fabric thread.