ELEMENTS TUBULAIRES COMPOSITES ET PROCEDES POUR LEUR FABRICATION

L'INVENTION CONCERNE UN ELEMENT TUBULAIRE RENFORCE DE FIBRES.SELON L'INVENTION, IL COMPREND UN TUBE CYLINDRIQUE 14 EN METAL AYANT UN AXE LONGITUDINAL; UNE COUCHE 32 D'ISOLEMENT ENTOURANT LE TUBE ET ADHERANT A SA SURFACE EXTERNE; UNE COUCHE DE FICHES DE RENFORCEMENT 34 ENTOURANT LE TUBE ET ADHERANT A LA SURFACE EXTERNE DE LA COUCHE D'ISOLEMENT, LA COUCHE DE FIBRES DE RENFORCEMENT CONTENANT UN CERTAIN NOMBRE DE FIBRES INDIVIDUELLES ET INDEPENDANTES DE RENFORCEMENT QUI SONT UNIFORMEMENT PLACEES SUR LA CIRCONFERENCE DU TUBE; ET UNE COUCHE DE RECOUVREMENT 36 ENTOURANT LE TUBE ET ADHERANT A LA SURFACE EXTERNE DE LA COUCHE DE FIBRES DE RENFORCEMENT.L'INVENTION S'APPLIQUE NOTAMMENT AUX ARBRES DE TRANSMISSION POUR VEHICULES AUTOMOBILES. A tubular element eg. for a drive shaft includes an aluminum tube (14) surrounded by a fiber composite sleeve (12) which comprises a plurality of individual reinforcing graphite fibers (34) oriented parallel to the longitudinal axis of the tube (14) and uniformly positioned about the circumference of the tube (14). An isolation layer (32) may be positioned between the graphite reinforcing layer (34) and the outer surface of the tube (14), and a protective covering layer (36) of fiber material may surround and be adhered to the outer surface of the graphite reinforcing layer (34). To form the tubular element a plurality of tubes (14) are coupled end-to-end by plugs (42), and fed along a longitudinal axis to an apparatus for applying the individual covering layers (32-36). As the tubes having the cured composite sleeve thereon exits the apparatus, the tubes are severed at each of the plugs (42) to produce a plurality of individual fiber reinforced tubular elements.