Filter underdrain module and underdrain system
CA 2120612 A1 · Owner: Neuspiel, Peter J. · Inventors: Neuspiel, Peter J.
Overview
Its claims, description and drawings are in the Canadian Patents Database.
Open the CIPO recordAbstract From the Canadian patent
A filter underdrain module (52) for an underdrain system (30) for a granular media filter. The module is an elongated integrally constructed, self-, contained unit having an enclosed interior and having a substantially flat substantially rectangular exterior top wall (53). The water and air for simultaneous backwashing and scouring the filter media are separately conveyed by conduits within the module, and separately discharged into the filter support bed (72) or directly into the filter media, as the case may be. The discharge openings for water (50) are all substantially the same shape and size and substantially, uniformly spaced along the length and breadth of the module. The same is …
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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 August 5, 1993. No grant is recorded for it in Canada; had it been granted, its 20-year term would have ended August 5, 2013.
- A certificate of supplementary protection adds at most two years for a drug, so even that would have ended by August 5, 2015.
- 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.