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Control circuit

US 2,431,237 A · Inventors: FREEMAN KEITH L

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1 drawing sheet

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Listed from its USPTO record in Patent Yard's full-term archive. Its claims, description and drawings are in the USPTO PDF and on Google Patents, and the Claude kit works from them.

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Why it's free to use

  • Granted November 18, 1947. A patent granted before 1976 lasted at most 17 years from grant, so its term ended by November 18, 1964.
  • We check US rights only. Old patents can still inspire new ones: improvements may be patentable.
FiledOctober 19, 1945
GrantedNovember 18, 1947
Term endedNovember 18, 1964
Application number—
Classification (CPC)G05B11/013
Length3 pages

Sources & verification

Official USPTO records

Full published documentText and every drawing sheet as a PDF.USPTOFile historyStatus, office actions, notices, fee records and petitions.USPTO Patent CenterPatent Public Search recordSearchable full text and bibliographic data.USPTO

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