Expired Canadian patentCanada
Liquid resistance switch for electrical purposes
CA 83280 A · Owner: Wooliscroft, John Harold · Inventors: Wooliscroft, John Harold
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 October 6, 1903. A Canadian patent filed before October 1, 1989 lasted 17 years from grant, so its term ended October 6, 1920.
- We check Canadian rights only. A patent in its family in another country could still be in force: check its family on Google Patents.
FiledMay 11, 1903
GrantedOctober 6, 1903
Term endedOctober 6, 1920
Patent numberCA 83280 A
Classification (IPC)—
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.