Heat exchanger tube and method of manufacturing same
CA 2272421 C · Owner: Roffelsen, Franciscus · Inventors: Roffelsen, Franciscus
Overview
Its claims, description and drawings are in the Canadian Patents Database.
Open the CIPO recordAbstract From the Canadian patent
Heat exchanger tube (4; 4') composed of a metal outer tube (2; 2') having inner profile (8; 8') and a metal inner tube (3; 3') having outer profile (9; 9'), wherein the profiles are in undercut engagement with each other so that the inner and outer tubes are in rigid abutment without play and at least one , longitudinal channel (10 11; 10', 11') is provided for leak detection formed , between the outer tube and the inner tube. The heat exchanger tube can be manufactured by designing the profiles so that the inner and outer tubes can be screwed or slid one into the other, after which the tubes can be brought into a play-free, rigidly abutting configuration through deformation for , …
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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 November 24, 1997 and granted September 23, 2003. A Canadian patent filed from October 1, 1989 lasts 20 years from filing, so its term ended November 24, 2017.
- A certificate of supplementary protection adds at most two years for a drug, so even that would have ended by November 24, 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.