Series connected light string with filament shunting
CA 2255641 C · Owner: Jay Cavender, Inc. · Inventors: Janning, John L.
Overview
Its claims, description and drawings are in the Canadian Patents Database.
Open the CIPO recordAbstract From the Canadian patent
A string of series connected incandescent bulbs (12-21) in which substantially all of the bulb filaments in the set are individually provided with a shunt element (31) which is inoperative during the normal operation of the set and is operative to provide the shunt only when an increase in the voltage across the shunt element exceeded a predetermined value, whereby continued flow of rated current continues to flow through said string even though a plurality of bulbs are missing from their respective sockets.
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 3, 1997 and granted June 25, 2002. A Canadian patent filed from October 1, 1989 lasts 20 years from filing, so its term ended February 3, 2017.
- A certificate of supplementary protection adds at most two years for a drug, so even that would have ended by February 3, 2019.
- 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.