Ballast for fluorescent lamp
CA 2282879 A1 · Owner: Miyazaki, Koji · Inventors: Ozawa, Masataka; Miyazaki, Koji; Murakami, Masanobu
Overview
Its claims, description and drawings are in the Canadian Patents Database.
Open the CIPO recordAbstract From the Canadian patent
A ballast for a fluorescent lamp includes a high frequency power source circuit for supplying a preheat start type fluorescent lamp with preheating and lighting current via an inductor. The high frequency power source circuit includes at least two switching elements for controlling application of voltages of different polarity to the fluorescent lamp a self, exciting type switching element driving circuit for driving the switching elements so as to alternate on and off repeatedly; and a timer circuit for detecting lapse of a predetermined time from start of the ballast for the fluorescent lamp. The switching element driving circuit shortens an ON-period of at least one of the switching …
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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 20, 1999. No grant is recorded for it in Canada; had it been granted, its 20-year term would have ended September 20, 2019.
- A certificate of supplementary protection adds at most two years for a drug, so even that would have ended by September 20, 2021.
- 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.