Multiple light level fluorescent lamp unit
CA 1189134 A · Owner: General Electric Company · Inventors: Beck, Charles E.
Overview
Its claims, description and drawings are in the Canadian Patents Database.
Open the CIPO recordAbstract From the Canadian patent
An integral self-contained gas discharge lamp unit including control circuitry wherein a plurality of electrically parallel ballast resistors are electrically connected in series with a pair of spaced filaments contained in a gas discharge lamp. Electrical switching means is provided to ensure and facilitate starting by electrically connecting at least two parallel ballast resistors to the rest of the control circuitry when starting the lamp unit. Additional electrical switching means enables the lamp unit to be operated at multiple light levels. The electrical switching means to ensure and facilitate starting is automatically controlled while electrical switching means to operate the lamp …
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
- Granted June 18, 1985. A Canadian patent filed before October 1, 1989 lasted 17 years from grant, so its term ended June 18, 2002.
- 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.