Photo switching device
CA 2354088 A1 · Owner: Cheng, Ching Chi · Inventors: Cheng, Ching Chi
Overview
Its claims, description and drawings are in the Canadian Patents Database.
Open the CIPO recordAbstract From the Canadian patent
A photo switching device includes first and second terminals respectively coupled to a power source and a load. A bi-directional current routing circuit including a rectifying bridge is connected to the first, and second terminals to receive electricity from the first and second terminals and has positive and negative output terminals. A switching/driving circuit is connected between the positive and negative output terminals for selectively conducting an output current of the bi-directional current routing circuit from the positive output terminal to the negative output terminal. The switching/driving circuit includes a silicon controlled switching device having a gate coupled to and …
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 July 25, 2001. No grant is recorded for it in Canada; had it been granted, its 20-year term would have ended July 25, 2021.
- A certificate of supplementary protection adds at most two years for a drug, so even that would have ended by July 25, 2023.
- 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.