Expired Canadian patentCanada
Thermionic amplifier
CA 218067 A · Owner: The International Western Electric Company · Inventors: The Western Electric Company
Overview
Drawings and full text
Its claims, description and drawings are in the Canadian Patents Database.
Open the CIPO recordRead the whole patent
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 April 25, 1922. A Canadian patent filed before October 1, 1989 lasted 17 years from grant, so its term ended April 25, 1939.
- 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—
GrantedApril 25, 1922
Term endedApril 25, 1939
Patent numberCA 218067 A
Classification (IPC)H01J
Timeline
Timeline From CIPO dates
Sources & verification
Official CIPO records
Everything on this page comes from the CIPO record linked above. Contains information licensed under the Open Government Licence – Canada.