Method for manufacturing an improved overhead and underground cable lead-in cable for voice, data and video transmission services

摘要

A method of manufacturing an improved overhead or underground telephone lead-in cable for transmission services VVDL (voice, video, data and lead-in) that permits the connection of the users to the public telephone system with a high speed digital service link, besides the analog services required. The cable has at least one or a plurality of transmission circuits. One of the transmission circuit is formed by two metal conductor elements cooperating in turn to self-support the cable or a conventional type of impregnated fibers or kevlar tape. The second circuit which is formed by a stranded pair of conductors is impregnated with a swelling powder preventing moisture penetration.

主权项

1. A method for manufacturing an overhead or underground telephone lead-in cable for voice, video and data (VVDL) transmission services, said cable comprising a core having self supporting member comprising conducting elements impregnated with moisture absorbing swelling powder, said method comprising the steps of:
a) constructing a rectangular structure comprising a rectangular outer cover having a geometrical shape comprising a thermoplastic material; b) arranging positioning at least one or a plurality of transmission circuits; forming a first transmission circuit by extruding a self-supporting member with the thermoplastic material to form an extruded cover; said self-supporting member comprising two conducting elements upwardly projecting therefrom the rectangular structure; said conducting elements comprising a material selected from a group consisting of metal, alloys, fiberglass and combinations thereof; c) arranging conducting elements at opposite ends, in parallel, and in turn are diametrically opposed to the first transmission circuit; d) forming a second transmission circuit with the cable comprising the core having a pair of stranded conductors at a center of the rectangular structure; e) insulating each one of the stranded conductors with a thermoplastic compound layer; applying die insulation continuously and uniformly such that concentricity of a wall of insulating material with regard to the conductor is higher than 90-92%; and colored for identification purposes; f) electrostatically depositing and positioning a swelling material layer as a moisture absorbing protection surrounding the core; arranging said swelling material layer between an area around a thin thermoplastic sleeve and the core of the stranded conductors and impregnating spaces with the swelling material layer; g) applying helicoidally or longitudinally a the thin thermoplastic sleeve as a fusion protective tape material which is temperature resistant material on the pair of stranded conductors to resist a temperature of up 240° C.; controlling wall thickness and helix of each one of the stranded conductors to obtain a characteristic impedance stability at relatively high frequency; h) helically uniting the fusion protective tape material with the swelling material layer and the core: said fusion protective tape material selected from the group consisting of polymers, kevlar tapes and mylar tapes: i) trimming edges at a corner of the rectangular structure and recesses at lateral ends to provide a lower tensile stress; and j) reinforcing the extruded cover with the thermoplastic material to form the lead-in cable; and k) developing cable constructions of from at least 16 AWG to 26 AWG conductors as components of the core.