Nozzleless underdrain for granular filtration system
CA 2080096 C · Owner: Shea, Edward M. · Inventors: Shea, Edward M.; Scott, J. Holland
Overview
Its claims, description and drawings are in the Canadian Patents Database.
Open the CIPO recordAbstract From the Canadian patent
A self-supporting modular underdrain member for use in a liquid filtration system comprises a main body or housing including a peir of longitudinally extending inclined walls which may have a pair of generally triangular transverse walls connecting the inclined walls to one another the inclined walls, each being provided with a pair of longitudinally extending recesses and a plurality of orifices communicating with each of the recesses. A pair of flanges are connected to the inclined walls for attaching the underdrain body to a floor surface so that the inclined walls, any transverse walls and the floor surface define a cross-sectionally triangular underdrain chamber. Two pairs of elongate …
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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 7, 1992 and granted December 1, 1998. A Canadian patent filed from October 1, 1989 lasts 20 years from filing, so its term ended October 7, 2012.
- A certificate of supplementary protection adds at most two years for a drug, so even that would have ended by October 7, 2014.
- 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.