Fluorescent lamp ballast
CA 2114989 A1 · Owner: Koninklijke Philips Electronics N.V. · Inventors: Garbowicz, Glenn D.
Overview
Its claims, description and drawings are in the Canadian Patents Database.
Open the CIPO recordAbstract From the Canadian patent
Fluorescent lamp ballast. A starting capacitor disconnect scheme for a fluorescent lamp in which each starting capacitor shunts one or more fluorescent lamps until all fluorescent lamps are ignited. Following ignition of all fluorescent lamps each starting capacitor is, effectively removed from the ballast. Preconditioning of the fluorescent lamp filaments can be limited to the period of time that one or more lamp loads are shunted by the starting capacitor.
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 4, 1994. No grant is recorded for it in Canada; had it been granted, its 20-year term would have ended February 4, 2014.
- A certificate of supplementary protection adds at most two years for a drug, so even that would have ended by February 4, 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.