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Emergency-call device

US 1,581,981 A · Inventors: PHELPS WENDELL H

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Overview

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 April 20, 1926. A patent granted before 1976 lasted at most 17 years from grant, so its term ended by April 20, 1943.
  • We check US rights only. Old patents can still inspire new ones: improvements may be patentable.
FiledMarch 10, 1924
GrantedApril 20, 1926
Term endedApril 20, 1943
Application number—
Classification (CPC)G09F7/00
Length3 pages

Timeline

Timeline From USPTO dates

1925192719291931193319351937193919411943Application filedMarch 10, 1924Patent grantedApril 20, 1926Term endedApril 20, 1943

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.