Flexible flat cable

{
  "publication_number": "US4567321A",
  "country": "US",
  "kind": "A",
  "title": "Flexible flat cable",
  "abstract": "An improved, highly flexible flat multi-conductor electrical cable is provided, useful for example in robots wherein such cables may be flexed many times, comprising a plurality of conductor assemblies held in parallel relationship between layers of insulating coverings, the improvement comprising conductor assemblies having an elongate, non-conductive center core filament helically overwrapped along its longitudinal dimension by a first conductor in foil or tape form, such as copper foil, this first tape conductor having an outer covering of a conductive, low-friction material, the conductive covering being helically overwrapped along its longitudinal dimension by a second conductor in foil or tape form, such as copper foil, the second foil conductor being wrapped in a lay opposite to that of the first conductor, i.e. if one foil conductor is \"S\" wrapped, the other foil conductor is \"Z\" wrapped. A preferred core filament material is expanded, porous, sintered polytetrafluoroethylene, and a preferred conductive covering is conductive, unsintered polytetrafluoroethylene. Preferred insulating coverings are layers of polytetrafluoroethylene.",
  "claims": [
    "1. An improved, highly flexible flat multi-conductor electrical cable comprising a plurality of conductor assemblies held in parallel relationship between layers of insulating coverings, the improvement comprising conductor assemblies having an elongate, non-conductive center core filament helically overwrapped along its longitudinal dimension by a first conductor in foil or tape form, this first tape conductor having an outer covering of a conductive, low friction material, said conductor covering being helically overwrapped along its longitudinal dimension by a second conductor in foil or tape form, said second foil conductor being wrapped having a lay different from that of said first conductor.",
    "2. The cable of claim 1 wherein said second conductor has a lay opposite to that of said first conductor.",
    "3. The cable of claim 1 wherein said foil conductors are copper foils.",
    "4. The cable of claim 1 wherein said core filament is a filament selected from the class consisting of nylon fiber or polytetrafluoroethylene filament.",
    "5. The cable of claim 1 wherein said core filament is expanded, porous, sintered polytetrafluoroethylene filament.",
    "6. The cable of claim 1 wherein said conductive covering is a covering of conductive polytetrafluoroethylene.",
    "7. The cable of claim 6 wherein said polytetrafluoroethylene is unsintered.",
    "8. The cable of claim 1 wherein said insulating coverings are layers of polytetrafluoroethylene."
  ],
  "cpc": [
    "H01B 7/0009",
    "H01B 7/0838"
  ],
  "assignees": [
    "JUNKOSHA CO LTD"
  ],
  "filing_date": "1984-09-24",
  "publication_date": "1986-01-28",
  "grant_date": "1986-01-28",
  "priority_date": "1984-02-20",
  "application_number": "US-65376284-A",
  "family_id": "12108051",
  "citations": [
    "GB1107405A",
    "US2998840A",
    "US3234722A",
    "US3760319A",
    "US4218581A",
    "US4313645A",
    "US4423282A",
    "US4443657A"
  ]
}