{
  "patent_number": "US 1781541",
  "country": "US",
  "title": "How Albert Einstein and Leo Szilard Designed a Silent Refrigerator",
  "original_title": "Refrigeration",
  "summary": "A 1930 patent by Albert Einstein and Leo Szilard for a refrigerator that uses electromagnetic pumps instead of moving mechanical parts to circulate coolant.",
  "what_it_does": "The patent describes an absorption refrigerator system that eliminates the need for moving parts like pistons or electric motors, which were prone to failure and leaks in early refrigeration technology. It uses an electromagnetic pump to circulate a refrigerant fluid through a closed loop. By leveraging the interaction between an electric current and a magnetic field, the system moves the liquid coolant without any mechanical wear, aiming for a design that is silent and durable.",
  "what_it_does_not_cover": [
    "Does not cover standard vapor-compression refrigerators that use traditional electric compressors.",
    "Does not cover refrigerators using chemical refrigerants like Freon or modern hydrofluorocarbons.",
    "Does not cover systems that rely on mechanical pumps or rotating fans to move coolant."
  ],
  "filed": "1927-12-16",
  "granted": "1930-11-11",
  "expires": "1947-12-16",
  "status": "expired",
  "holder": "Electrolux Servel Corp",
  "holder_url": "https://patentbrief.org/company/electrolux-servel-corp",
  "inventors": [
    {
      "name": "Einstein Albert",
      "url": "https://patentbrief.org/inventor/einstein-albert"
    },
    {
      "name": "Szilard Leo",
      "url": "https://patentbrief.org/inventor/szilard-leo"
    }
  ],
  "times_cited": 22,
  "tags": [
    "mechanical",
    "energy"
  ],
  "abstract": null,
  "url": "https://patentbrief.org/patent/us/1781541/einstein-szilard-refrigerator",
  "markdown_url": "https://patentbrief.org/patent/us/1781541/einstein-szilard-refrigerator/md",
  "google_patents_url": "https://patents.google.com/patent/US1781541",
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}