{
  "patent_number": "US 3668658",
  "country": "US",
  "title": "How the Floppy Disk's Protective Jacket Cleans the Disk",
  "original_title": "Magnetic record disk cover",
  "summary": "An IBM patent from 1972 describing a protective, non-removable cover for a magnetic disk that uses a built-in cleaning material to wipe the disk surface while it spins.",
  "what_it_does": "This patent describes a protective sleeve for a magnetic disk that remains stationary while the disk spins inside it. The inside of this sleeve is lined with a special porous, antistatic material that stays in physical contact with the disk surface. As the disk rotates, this lining acts like a constant wiper, removing dust and contaminants that could otherwise cause read or write errors. The cover also includes a specific opening, or transducing aperture, which allows the magnetic read/write head of the computer drive to touch the disk surface to access data.",
  "what_it_does_not_cover": [
    "Does not cover disks that are intended to be removed from their protective covers by the user.",
    "Does not cover storage systems where the disk and the protective cover rotate together as a single unit.",
    "Does not cover cleaning mechanisms that are separate from the disk's permanent housing.",
    "Does not cover optical storage media like CDs or DVDs."
  ],
  "filed": "1969-12-22",
  "granted": "1972-06-06",
  "expires": "1989-12-22",
  "status": "expired",
  "holder": "International Business Machines Corp",
  "holder_url": "https://patentbrief.org/company/international-business-machines-corp",
  "inventors": [
    {
      "name": "Ralph Flores",
      "url": "https://patentbrief.org/inventor/ralph-flores"
    },
    {
      "name": "Herbert E Thompson",
      "url": "https://patentbrief.org/inventor/herbert-e-thompson"
    }
  ],
  "times_cited": 79,
  "tags": [
    "consumer_electronics",
    "mechanical",
    "semiconductors"
  ],
  "abstract": "In a magnetic recording system, the combination comprising a rotary magnetic record disk and a cover for containing the disk. The cover has its inner surfaces in frictional contact with the adjacent surfaces of the disk. Furthermore, the disk is rotatable while the cover is maintained stationary in the magnetic recording system. The cover includes means for cleaning the surface of the disk during rotation of the disk.",
  "url": "https://patentbrief.org/patent/us/3668658/floppy-disk-diskette",
  "markdown_url": "https://patentbrief.org/patent/us/3668658/floppy-disk-diskette/md",
  "google_patents_url": "https://patents.google.com/patent/US3668658",
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}