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Apparatus for interrupting alternating currents

US 2,351,975 A · Inventors: FLORIS KOPPELMANN

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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 June 20, 1944. A patent granted before 1976 lasted at most 17 years from grant, so its term ended by June 20, 1961.
  • We check US rights only. Old patents can still inspire new ones: improvements may be patentable.
FiledDecember 9, 1936
GrantedJune 20, 1944
Term endedJune 20, 1961
Application number—
Classification (CPC)H02M7/34
Length21 pages

Timeline

Timeline From USPTO dates

193719401943194619491952195519581961Application filedDec 9, 1936Patent grantedJune 20, 1944Term endedJune 20, 1961

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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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