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Expired Canadian patentCanada

Electron tube

CA 444666 A · Owner: Philco Radio And Television Corporation · Inventors: John S. Vansant

CIPO record

Overview

Drawings and full text

Its claims, description and drawings are in the Canadian Patents Database.

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Listed from its CIPO record in Patent Yard's archive of Canadian patents past their term. Its claims, description and drawings are in the CIPO record and on Google Patents, and the Claude kit works from them.

Why it's free to use

  • Granted October 21, 1947. A Canadian patent filed before October 1, 1989 lasted 17 years from grant, so its term ended October 21, 1964.
  • We check Canadian rights only. A patent in its family in another country could still be in force: check its family on Google Patents.
Filed—
GrantedOctober 21, 1947
Term endedOctober 21, 1964
Patent numberCA 444666 A
Classification (IPC)H01J1/88 +1 more

Timeline

Timeline From CIPO dates

194819501952195419561958196019621964Patent grantedOct 21, 1947Term endedOct 21, 1964

Sources & verification

Everything on this page comes from the CIPO record linked above. Contains information licensed under the Open Government Licence – Canada.