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US 1,853,687 A · Inventors: KIMMELL WILLIAM J

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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.

Why it's free to use

  • Granted April 12, 1932. A patent granted before 1976 lasted at most 17 years from grant, so its term ended by April 12, 1949.
  • We check US rights only. Old patents can still inspire new ones: improvements may be patentable.
FiledMay 12, 1927
GrantedApril 12, 1932
Term endedApril 12, 1949
Application number—
Classification (CPC)H01J19/28 +1 more
Length4 pages

Timeline

Timeline From USPTO dates

19281931193419371940194319461949Application filedMay 12, 1927Patent grantedApril 12, 1932Term endedApril 12, 1949

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