Switch with current flow detector
CA 2216263 A1 · Owner: Ridgeway Research Corporation · Inventors: Kiss, Bill; Neathway, Graham
Overview
Its claims, description and drawings are in the Canadian Patents Database.
Open the CIPO recordAbstract From the Canadian patent
A switch for use in an AC circuit wired in a three-way switch mode for supplying power to a load has a first, terminal for-connection to an external line second and, third terminals for connection respectively to corresponding terminals of a second like switch, and a switch contact for selectively connecting the first terminal to either one of the second and third terminals. A transformer has its primary winding connected between the first terminal and the external line, and its secondary winding deriving an output voltage therefrom. The output voltage is rectified and supplied to a light-emitting diode. The ratio of turns of the windings of the transformer is such that the rectified …
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 September 23, 1997. No grant is recorded for it in Canada; had it been granted, its 20-year term would have ended September 23, 2017.
- A certificate of supplementary protection adds at most two years for a drug, so even that would have ended by September 23, 2019.
- 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.