Operating device for discharge lamps having a preheating device
CA 2415512 A1 · Owner: Patent-Treuhand-Gesellschaft Fuer Elektrische Gluehlampen Mbh · Inventors: Schemmel, Bernhard; Busse, Olaf; Weirich, Michael
Overview
Its claims, description and drawings are in the Canadian Patents Database.
Open the CIPO recordAbstract From the Canadian patent
The invention relates to an operating circuit for a low-pressure discharge lamp LP, in which the lamp electrodes can be preheated by means of a resonant circuit C14, T11. In order to determine the resonant frequency accurately and to establish the lamp type being used, a frequency range is moved through at the start of operation and the voltage is measured on a primary winding T11 of a preheating transformer.
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 30, 2002. No grant is recorded for it in Canada; had it been granted, its 20-year term would have ended December 30, 2022.
- A certificate of supplementary protection adds at most two years for a drug, so even that would have ended by December 30, 2024.
- 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.