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Cylinder head for two-cycle doublebore-cylinder internal combustion engines

US 2,142,004 A · Inventors: AUGUST PORTMANN

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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 December 27, 1938. A patent granted before 1976 lasted at most 17 years from grant, so its term ended by December 27, 1955.
  • We check US rights only. Old patents can still inspire new ones: improvements may be patentable.
FiledAugust 16, 1937
GrantedDecember 27, 1938
Term endedDecember 27, 1955
Application number—
Classification (CPC)F02B75/18
Length4 pages

Timeline

Timeline From USPTO dates

193819401942194419461948195019521954Application filedAug 16, 1937Patent grantedDec 27, 1938Term endedDec 27, 1955

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

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