Tubular heating element with insulating core
CA 2212342 C · Owner: Hall, Bertie Forrest Jr. · Inventors: Hall, Bertie Forrest Jr.
Overview
Its claims, description and drawings are in the Canadian Patents Database.
Open the CIPO recordAbstract From the Canadian patent
A tubular heating element (10) having a metal tube (12) filled with a ceramic material (14). The metal tube has a near zero or slightly positive temperature coefficient of resistance. In an alternative embodiment a wire (16) is , coaxially supported within the metal tube (12) by the ceramic material (14). This wire may be used to stiffen the tubular heating element (10) or may be used as an electrical conductor.
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 21, 1995 and granted May 16, 2000. A Canadian patent filed from October 1, 1989 lasts 20 years from filing, so its term ended February 21, 2015.
- A certificate of supplementary protection adds at most two years for a drug, so even that would have ended by February 21, 2017.
- 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.