Switching power source
CA 2057310 C · Owner: Motomura, Hiroyuki · Inventors: Miyazawa, Shigeo; Motomura, Hiroyuki; Takizawa, Mikinao
Overview
Its claims, description and drawings are in the Canadian Patents Database.
Open the CIPO recordAbstract From the Canadian patent
A resonant type switching power source implementing zero voltage switching on the basis of the resonance between an inductor and a capacitor. A main switch is connected to the primary side of a main transformer. A pulse width control circuit generates a control signal for varying the turn-on time of the main switch until the output voltage of the secondary side of the tranformer being fed back reaches a predetermined value. A resonance capacitor is connected in parallel with the main witch. When the terminal voltage of the capacitor crosses zero potential toward the negative side, the pulse width control circuit delivers an ON command to the main switch. Alternatively the ON, control over …
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 9, 1991 and granted October 28, 1997. A Canadian patent filed from October 1, 1989 lasts 20 years from filing, so its term ended December 9, 2011.
- A certificate of supplementary protection adds at most two years for a drug, so even that would have ended by December 9, 2013.
- 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.