Multiple contour screening
CA 2222746 C · Owner: Frejborg, Frey · Inventors: Frejborg, Frey
Overview
Its claims, description and drawings are in the Canadian Patents Database.
Open the CIPO recordAbstract From the Canadian patent
A screen cylinder or plate with a screening surface (11) for separating accepts from rejects, the surface including a number of parallel macro grooves (22) and a number of parallel micro grooves (24) formed within each macro groove generally transverse to the flow direction. The macro grooves induce shear stress in the reject material preventing it from forming a mat on the screening surface. The micro grooves induce micro turbulence into the pulp at the screening openings (27) improving accepts flow through the openings. Each micro groove within a macro groove is located further away from the accepts surface (12) moving in the flow direction. The contour of each micro groove …
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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 May 31, 1996 and granted February 18, 2003. A Canadian patent filed from October 1, 1989 lasts 20 years from filing, so its term ended May 31, 2016.
- A certificate of supplementary protection adds at most two years for a drug, so even that would have ended by May 31, 2018.
- 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.