Patent ID: 7377763
Filing Date: 2008-05-27
Classification: B29C,B29K,H01B

Abstract:
1. An extrusion apparatus for producing a cable including a core comprising at least one transmissive element, and at least one pair of coating layers arranged at a radially outer position with respect to said core comprising an extrusion head, said extrusion head including: a) a male die, a female die, and at least one intermediate die coaxially mounted between the male die and the female die around a longitudinal axis substantially parallel to an advancing direction of said core; b) a longitudinal cavity configured to receive said core defined in said male die; c) at least one pair of feeding channels defined in said extrusion head and intended for depositing by co-extrusion, respectively, at least one coating layer of polymeric material and one coating layer of expanded polymeric material a first feeding channel, defined in part by the male die, for depositing a first coating layer including a polymeric material on said core before said first coating layer exits said intermediate die, and a second feeding channel for depositing a second coating layer including an expanded polymeric material on said core after said second coating layer exits said female die; and d) a plurality of suction channels intended for sucking configured to suck the gases released during an expansion of said second coating layer including an expanded polymeric material, said suction channels being defined in said extrusion head between said feeding channels.