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Electric discharge apparatus

US 1,867,390 A · Inventors: THOMPSON BROWDER 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 July 12, 1932. A patent granted before 1976 lasted at most 17 years from grant, so its term ended by July 12, 1949.
  • We check US rights only. Old patents can still inspire new ones: improvements may be patentable.
FiledAugust 2, 1928
GrantedJuly 12, 1932
Term endedJuly 12, 1949
Application number—
Classification (CPC)H01J19/42 +1 more
Length4 pages

Timeline

Timeline From USPTO dates

1929193219351938194119441947Application filedAug 2, 1928Patent grantedJuly 12, 1932Term endedJuly 12, 1949

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