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Hydraulic spring closing mechanism for circuit breakers-prevention of unintentional closing

US 2,922,011 A · Inventors: MITCHELL HAROLD H

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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 January 19, 1960. A patent granted before 1976 lasted at most 17 years from grant, so its term ended by January 19, 1977.
  • We check US rights only. Old patents can still inspire new ones: improvements may be patentable.
FiledJuly 1, 1957
GrantedJanuary 19, 1960
Term endedJanuary 19, 1977
Application number—
Classification (CPC)H01H3/301
Length8 pages

Timeline

Timeline From USPTO dates

1958196019621964196619681970197219741976Application filedJuly 1, 1957Patent grantedJan 19, 1960Term endedJan 19, 1977

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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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