Expired Canadian patentCanada
System providing a d. c. voltage equal to the r.m.s. value of an unknown a. c. voltage
CA 922376 A · Owner: Ballantine Laboratories · Inventors: James J. Duckworth; Norbert Schnog; Alfred B. Muller
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 March 6, 1973. A Canadian patent filed before October 1, 1989 lasted 17 years from grant, so its term ended March 6, 1990.
- 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—
GrantedMarch 6, 1973
Term endedMarch 6, 1990
Patent numberCA 922376 A
Classification (IPC)G01R19/22 +1 more
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.