Screening device for a fiber slurry, and a backwash means therefor
CA 2124778 C · Owner: Young, Douglas L. G. · Inventors: Young, Douglas L. G.
Overview
Its claims, description and drawings are in the Canadian Patents Database.
Open the CIPO recordAbstract From the Canadian patent
A hydrofoil in close proximity to an outboard surface of a rotatable slurry screen, and a hydrofoil in close proximity to an inboard surface of the screen cooperate to create high and low slurry pressures at the surfaces which result in causing the slurry to surge through the screen to backwash the latter thereby, dislodging slurry-borne substances which tend to clog apertures in the screen.
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 May 31, 1994 and granted May 4, 1999. A Canadian patent filed from October 1, 1989 lasts 20 years from filing, so its term ended May 31, 2014.
- A certificate of supplementary protection adds at most two years for a drug, so even that would have ended by May 31, 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.