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Toothbrush

US 1,820,439 A · Inventors: GORDON CHURCH ROBERT JAMES

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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 August 25, 1931. A patent granted before 1976 lasted at most 17 years from grant, so its term ended by August 25, 1948.
  • We check US rights only. Old patents can still inspire new ones: improvements may be patentable.
FiledNovember 21, 1929
GrantedAugust 25, 1931
Term endedAugust 25, 1948
Application number—
Classification (CPC)A46B15/0071
Length3 pages

Timeline

Timeline From USPTO dates

1930193219341936193819401942194419461948Application filedNov 21, 1929Patent grantedAug 25, 1931Term endedAug 25, 1948

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