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US 1,659,870 A · Inventors: MARIA GRAHAM et al.

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The published document from the USPTO: abstract, claims, description and drawings. Open it full size

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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 February 21, 1928. A patent granted before 1976 lasted at most 17 years from grant, so its term ended by February 21, 1945.
  • We check US rights only. Old patents can still inspire new ones: improvements may be patentable.
FiledFebruary 18, 1926
GrantedFebruary 21, 1928
Term endedFebruary 21, 1945
Application number—
Classification (CPC)H04M1/24
Length8 pages

Timeline

Timeline From USPTO dates

1927192919311933193519371939194119431945Application filedFeb 18, 1926Patent grantedFeb 21, 1928Term endedFeb 21, 1945

Sources & verification

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

Cross-check elsewhere

Google PatentsFull text, worldwide family, citing patents and legal events.patents.google.comJustia PatentsFull text, claims and classification.patents.justia.comFreePatentsOnlineFull text and PDF.freepatentsonline.comEspacenetForeign family and legal status.European Patent Office

Everything on this page comes from the USPTO record linked above.