Short radius culvert sections
CA 2118145 C · Owner: Major, Jean-Louis · Inventors: Mccavour, Thomas C.; Major, Jean-Louis
Overview
Its claims, description and drawings are in the Canadian Patents Database.
Open the CIPO recordAbstract From the Canadian patent
Soil/metal supporting structures commonly include panel sections having a short radius of curvature in the range of 750 mm to 2,500 mm. In such soil metal supporting structures the panels are of heavy gauge in the range of 2 mm to 10 mm thickness. Usually expensive tooling and forming techniques are required to cold form the heavy gauge material into a curved shaped having such short radius. Such expensive techniques have been eliminated by this invention by virtue of the improvements comprising: a) the panels have a high degree of ductility before being cold formed such high degree of ductility being determined by a ratio of specified minimum yield strength to specified minimum tensile …
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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 October 14, 1994 and granted July 13, 1999. A Canadian patent filed from October 1, 1989 lasts 20 years from filing, so its term ended October 14, 2014.
- A certificate of supplementary protection adds at most two years for a drug, so even that would have ended by October 14, 2016.
- 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.