US 4,449,012 AGranted

Overhead cable with tension-bearing means

AssigneeKupferdraht-Isolierwerk AG Wildegg

InventorOthmar Voser

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Abstract

In known overhead telephone cables comprising two individual encased and stranded conductors, each consisting of a plurality of copper wires for the transmission of signals, and steel wires for load bearing purposes, the problem of relatively high susceptibility to corrosion at leakage points in the casing due to water penetration is solved by replacing the steel wires with bundles of stretch-resistant synthetic fibres, e.g. aromatic polyamide fibres, and the tendency of spirally wound synthetic fibres, or bundles of fibres, to shift towards the center of the conductor when the cable is under tension, and thus allow the cable to elongate is prevented by arranging the copper wires and bundles of fibres so that they position themselves mutually. The coherency of the bundles of fibres required for this purpose may be obtained, for example, by stranding or twisting the fibres in the bundle or impregnating the bundle with a resin, preferably colophony.

Claims19

Dependent claims

An overhead cable comprises at least two conductors each comprising a plurality of metal wires for signal transmission and a plurality of substantially non-extensible load-bearing substantially circular helically stranded fiber bundles, both said wires and bundles extending generally in the longitudinal direction of the cable and being helically stranded together, and an exterior protective cover enclosing said wires and bundles, and a bridge connecting together the covers of each adjacent pair of conductors in said cable, said conductor having one metal wire or fibre bundle at the center thereof as a core, said plural metal wires and said circular fibre bundles other than said core being arranged generally symmetrically around the core axis at substantially equispaced peripheral points therearound with said wires and bundles in alternating relation, said symmetrically arranged wires being of like size and said symmetrically arranged bundles being of like size, each such bundle being in abutting contact with said core and the adjacent pair of wires.

Dependencies are inferred from the claim text.