{
  "patent_number": "US 723325",
  "country": "US",
  "title": "Leamon Souder's 1903 Design for a Spiral Escalator",
  "original_title": "Moving spiral stairway or elevator.",
  "summary": "A 1903 patent for a mechanical staircase that moves in a circular, spiraling path to transport people between floors.",
  "what_it_does": "The patent describes a mechanical system where steps are mounted on a continuous chain that follows a helical or spiral track. As the chain moves, the steps rise or descend while simultaneously rotating around a central axis. This design intended to save space compared to traditional straight escalators by allowing the stairs to fit into a circular shaft.",
  "what_it_does_not_cover": [
    "Does not cover standard linear escalators that move in a straight line.",
    "Does not cover elevators that use a vertical cable-and-pulley system.",
    "Does not cover stationary spiral staircases that lack a motorized moving mechanism."
  ],
  "filed": "1902-03-24",
  "granted": "1903-03-24",
  "expires": "1922-03-24",
  "status": "expired",
  "holder": "Individual",
  "holder_url": "https://patentbrief.org/company/individual",
  "inventors": [
    {
      "name": "Leamon G Souder",
      "url": "https://patentbrief.org/inventor/leamon-g-souder"
    }
  ],
  "times_cited": 17,
  "tags": [
    "mechanical",
    "automotive"
  ],
  "abstract": null,
  "url": "https://patentbrief.org/patent/us/723325/escalator-moving-stairway",
  "markdown_url": "https://patentbrief.org/patent/us/723325/escalator-moving-stairway/md",
  "google_patents_url": "https://patents.google.com/patent/US723325",
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}