Vacuum filtration system and method of filtering pulp fibers from pulp slurry using the same
CA 2109492 C · Owner: Groupe Laperriere & Verreault Inc. · Inventors: Brown, Rollin E.; Lewis, Frederick S.; Empie, Lewis F.
Overview
Its claims, description and drawings are in the Canadian Patents Database.
Open the CIPO recordAbstract From the Canadian patent
A method and apparatus for filtering pulp fibers from a pulp slurry, using a combination of vacuum hydrodynamic and, hydrostatic forces in order to achieve a more effective deposition of pulp fibers onto the filter surface and enhanced flow of filtrate through the cylinder. The apparatus is in the form of an improved vacuum filtration system in which the, filtrate outlet tube is disposed along the axis of rotation of the rotary cylinder and the filtrate inlet and outlet ports of each filtrate conduct are radially offset from one another in the direction of intended rotation of the cylinder. During various phases of filter operation, vacuum forces generated by the vacuum source cooperate …
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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 28, 1993 and granted September 15, 1998. A Canadian patent filed from October 1, 1989 lasts 20 years from filing, so its term ended October 28, 2013.
- A certificate of supplementary protection adds at most two years for a drug, so even that would have ended by October 28, 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.
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Everything on this page comes from the CIPO record linked above. Contains information licensed under the Open Government Licence – Canada.