{
  "patent_number": "US 2708656",
  "country": "US",
  "title": "How the First Nuclear Reactor Works",
  "original_title": "Neutronic reactor",
  "summary": "The foundational 1955 patent by Enrico Fermi and Leo Szilard describing the design of the first nuclear reactor capable of a self-sustaining chain reaction.",
  "what_it_does": "The patent defines the critical physical requirements for a nuclear reactor to achieve a self-sustaining chain reaction. It specifies a lattice structure where natural uranium rods are embedded in a graphite moderator. The claim explicitly links the geometry, the volume ratio of the graphite to the uranium, and the material purity to the 'k=1.00' curve, which represents the threshold where the number of neutrons produced equals the number of neutrons lost. By maintaining these precise parameters, the system ensures that the fission process continues without external intervention.",
  "what_it_does_not_cover": [
    "Does not cover reactors using enriched uranium fuel, as the claim specifies natural uranium.",
    "Does not cover non-graphite moderation systems, such as heavy water or light water reactors.",
    "Does not cover specific control rod mechanisms or safety shutdown systems."
  ],
  "filed": "1944-12-19",
  "granted": "1955-05-17",
  "expires": "1972-05-17",
  "status": "expired",
  "holder": "Individual",
  "holder_url": "https://patentbrief.org/company/individual",
  "inventors": [
    {
      "name": "Fermi Enrico",
      "url": "https://patentbrief.org/inventor/fermi-enrico"
    },
    {
      "name": "Szilard Leo",
      "url": "https://patentbrief.org/inventor/szilard-leo"
    }
  ],
  "times_cited": 232,
  "tags": [
    "energy",
    "mechanical"
  ],
  "abstract": null,
  "url": "https://patentbrief.org/patent/us/2708656/nuclear-reactor-fermi-szilard",
  "markdown_url": "https://patentbrief.org/patent/us/2708656/nuclear-reactor-fermi-szilard/md",
  "google_patents_url": "https://patents.google.com/patent/US2708656",
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}