Manufacture of a hollow envelope by winding filamentary material

摘要

The invention is concerned with the manufacture, by winding of filamentary material, of a hollow envelope of elongate shape the profile of which evolves along its longitudinal direction. An apparatus for this purpose comprises a deformable mandrel over which the filamentary material is wound, a mould in which the mandrel carrying the winding is enclosed, and a device for flattening the envelope so produced against the walls of a cavity in a mould. The cavity wall is in the shape of the external surface of the requried envelope. The deformable mandrel comprises a rigid core and a flexible wall which is movable with respect to the core to press the winding against the wall of the mould cavity. A device may be provided for ensuring the relaxation of the tension of the threads of the winding produced when the flexible wall is in its position pressing the envelope against the wall of the cavity.