Electrical fault detecting device
CA 2004890 A1 · Owner: Sheldon, Raymond · Inventors: Mutch, Alan Joseph; Sheldon, Raymond
Overview
Its claims, description and drawings are in the Canadian Patents Database.
Open the CIPO recordAbstract From the Canadian patent
An apparatus for determining incorrect usage of an alternating current electricity supply to a metering device, has first signal generating means disposed at, a first location in the supply for generating a first, signal which varies with a property of the electricity supply in the vicinity of the first location second, signal generating means, disposed at a second location in the supply, for generating a second signal which varies with a property of the electricity supply in the vicinity of the second location and monitoring and actuator means adapted to monitor the two signals and to produce a third, actuating signal when the first and second signals are inconsistent with a correct …
Read 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
- Filed December 7, 1989. No grant is recorded for it in Canada; had it been granted, its 20-year term would have ended December 7, 2009.
- A certificate of supplementary protection adds at most two years for a drug, so even that would have ended by December 7, 2011.
- We check Canadian rights only. A patent in its family in another country could still be in force: check its family on Google Patents.
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.