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US5151143A Expired / Lapsed US ⏱️ 0.0 years remaining

Moisture-impermeable electric conductor

Assignee: Phillips Cables Ltd
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Filing: 1991-05-22
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Granted: 1992-09-29
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Expires: 2011-05-22
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Abstract

Abstract In the manufacture of a cable core comprising a moisture-impermeable multi-wire conductor, the conductor is stranded in a conventional manner and, after a fluid-impermeable layer of plastics material has been extruded over the conductor to form the core, the core is wound around the hub of a cable drum in such a way that each end of the wound core is exposed and accessible. One exposed end of the wound core is sealed and air is evacuated from the conductor interstices by a vacuum pump cemented to the other exposed end of the wound core. A source of semi-conductive moisture-impermeable compound in a liquid or semi-liquid state is then connected to the exposed end of the wound core and moisture-impermeable compound is drawn into and flows along the evacuated conductor interstices until the interstices are filled throughout the length of the core. The moisture-impermeable compound in the interstices is then permitted to solidify or thicken to such an extent that it will not readily flow from the conductor.

Inventors

  • 👤 Ian Downie

Bibliographic Details

Application Number —
Jurisdiction US
Data Source google_patents
Last Synchronized 2026-11-05 10:53
CPC Classifications
H; H01; H01B; H01B13/00; H01B13/32; H01B13/322

Claims Analysis

Total Claims: 15
Claim 1
Independent Claim 241 words
A method of manufacturing an electric cable comprising at least one cable core having a substantially moisture-impermeable multi-wire electric conductor, which method comprises causing a flexible elongate core of metal or metal alloy to travel continuously in the direction of its length; helically winding around the advancing metal core at least one layer of wires to form a flexible multi-wire conductor; extruding over the multi-wire conductor at least one fluid-impermeable layer of plastics material to form an electric cable core; winding the cable core around the hub of a cable drum in such a way that each end of the wound cable core is exposed and accessible; sealing the end of the multi-wire conductor at one exposed end of the wound cable core and evacuating air from the interstices bounded by the wires of the multi-wire conductor from the other exposed end of the wound cable core; connecting a source of semi-conductive moisture-impermeable compound in a liquid or semi-liquid state to the end of the multi-wire conductor at one exposed end of the wound cable core and filling the interstices with moisture-impermeable compound by allowing moisture-impermeable compound to be drawn into and to flow along the interstices throughout the length of the multi-wire conductor until the interstices are substantially filled throughout the length of the conductor and permitting or causing the moisture-impermeable compound in said interstices to thicken to such an extent that it will not readily flow from the conductor.
Claim 2
Independent Claim 241 words
A method of manufacturing an electric cable comprising at least one cable core having a substantially moisture-impermeable multi-wire electric conductor, which method comprises causing a flexible elongate core of metal or metal alloy to travel continuously in the direction of its length; helically winding around the advancing metal core at least one layer of wires to form a flexible multi-wire conductor; extruding over the multi-wire conductor at least one fluid-impermeable layer of plastics material to form an electric cable core; winding the cable core around the hub of a cable drum in such a way that each end of the wound cable core is exposed and accessible; sealing the end of the multi-wire conductor at one exposed end of the wound cable core and evacuating air from the interstices bounded by the wires of the multi-wire conductor from the other exposed end of the wound cable core; connecting a source of semi-conductive moisture-impermeable compound in a liquid or semi-liquid state to the end of the multi-wire conductor at one exposed end of the wound cable core and filling the interstices with moisture-impermeable compound by allowing moisture-impermeable compound to be drawn into and to flow along the interstices throughout the length of the multi-wire conductor until the interstices are substantially filled throughout the length of the conductor and permitting or causing the moisture-impermeable compound in said interstices to thicken to such an extent that it will not readily flow from the conductor.
Claim 3
Dependent Claim 50 words
A method as claimed in claim 1 in which the electric cable core is to constitute the core of a single core electric cable, wherein before the cable core is wound around the hub of the cable drum, the method further comprises applying a cable sheath to the cable core.
Claim 4
Dependent Claim 81 words
A method as claimed in claim 1 in which the electric cable core is to constitute one core of a multi-core electric cable, wherein, before the cable core is wound around the hub of the cable drum, the method further comprises laying-up the cable core with at least one other cable core of similar construction, applying a cable sheath to the assembled cores to form a multi-core electric cable, and winding the electric cable around the hub of the cable drum.
Claim 5
Dependent Claim 44 words
A method as claimed in claim 3, wherein the method further comprises evacuating the multi-wire conductors of the cable cores of the wound multi-core cable and drawing moisture-impermeable compound in a liquid or semi-liquid state into the evacuated interstices of the multi-wire conductors concurrently.
Claim 6
Dependent Claim 27 words
A method as claimed in claim 1, wherein the method further comprises evacuating substantially all air from the interstices of the multi-wire conductor during the evacuating step.
Claim 7
Dependent Claim 55 words
A method as claimed in claim 1, wherein, before semi-conductive moisture-impermeable compound in a liquid or semi-liquid state is drawn into the interstices of the conductor, the method further comprises heating the multi-wire conductor of the wound core to prevent premature cooling and thickening of the compound as it is being drawn into the interstices.
Claim 8
Dependent Claim 20 words
A method as claimed in claim 6, wherein said heating is effected by passing an appropriate current along the conductor.
Claim 9
Dependent Claim 36 words
A method as claimed in claim 1, wherein the method further comprises evacuating air from the interstices of the multi-wire conductor of the wound cable core at the exposed leading end of the wound cable core.
Claim 10
Dependent Claim 43 words
A method as claimed in claim 8, wherein the method further comprises feeding the leading end of the wound cable core through a hole in a flange of the cable drum so that the leading end of the wound cable core protrudes therethrough.
Claim 11
Dependent Claim 74 words
A method as claimed in claim 1, wherein the method further comprises detachably connecting a vacuum pump to the end of the multi-wire conductor at the exposed end of the wound cable core, which vacuum pump incorporates means for temporarily sealing the end of said multi-wire conductor with respect to the vacuum pump, and evacuating air from the interstices of the multi-wire conductor of the wound cable core by means of said vacuum pump.
Claim 12
Dependent Claim 44 words
A method as claimed in claim 1, wherein the method further comprises detachably connecting to the end of said multi-wire conductor at the exposed trailing end of the wound cable core a source of said semi-conductive, moisture-impermeable compound in a liquid or semi-liquid state.
Claim 13
Dependent Claim 36 words
A method as claimed in claim 11, wherein the method further comprises effecting a temporary seal between said multi-wire conductor and the source of semi-conductive, moisture-impermeable compound whilst the interstices of said conductor are being evacuated.
Claim 14
Dependent Claim 39 words
A method as claimed in claim 11, wherein the method further comprises heating the source of semi-conductive, moisture-impermeable compound to maintain compound in the source at such a temperature that the compound is in said liquid or semi-liquid state.
Claim 15
Dependent Claim 77 words
A method as claimed in claim 1, wherein the method further comprises selecting a semi-conductive, moisture-impermeable compound which, when heated to a temperature of above approximately 150° C., is sufficiently liquified for the compound to be drawn into evacuated interstices of said multi-wire conductor of the wound cable core and which, when permitted to cool to a temperature below approximately 130° C., thickens to such an extent that the compound will not readily flow from the conductor.

References Cited (Backward Citations)

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US3615959A Cited
US3589121A Cited
US4125741A Cited
US4407854A Cited
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USPTO Annuity & Maintenance Windows

Annuity Stage Window Opens Payment Deadline Surcharge Period Until Estimated Fee Status
3.5 Years (Year 4) 1995-09-29 1996-03-30 1996-09-29 $2000.00 Window Closed / Lapsed
7.5 Years (Year 8) 1999-09-29 2000-03-30 2000-09-29 $3760.00 Window Closed / Lapsed
11.5 Years (Year 12) 2003-09-29 2004-03-30 2004-09-29 $7700.00 Window Closed / Lapsed

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