Overvoltage protection circuit
CA 2115852 C · Owner: Kanai, Takeo · Inventors: Kusunoki, Kiyoshi; Kanai, Takeo
Overview
Its claims, description and drawings are in the Canadian Patents Database.
Open the CIPO recordAbstract From the Canadian patent
An overvoltage protection circuit including a plurality of series connected thyristors having an overvoltage protection function and a plurality of impedance circuits. Each of the impedance circuits is connected in parallel with one of the thyristors, respectively. The impedance circuits include at least a first impedance circuit having a first impedance value and a second impedance circuit having a second impedance value which is different from the first impedance value.
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 February 17, 1994 and granted July 6, 1999. A Canadian patent filed from October 1, 1989 lasts 20 years from filing, so its term ended February 17, 2014.
- A certificate of supplementary protection adds at most two years for a drug, so even that would have ended by February 17, 2016.
- 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.