Apparatus for crushing or grinding of fibrous material, in particular drum refiner
CA 1320864 C · Owner: Maschinenfabrik Andritz Actiengesellschaft · Inventors: Bernhard, Emmerich; Henriksson, Sven-Erik; Lileg, Johann
Overview
Its claims, description and drawings are in the Canadian Patents Database.
Open the CIPO recordAbstract From the Canadian patent
The invention relates to a crushing or grinding element for drum refiners for the crushing or grinding of fibrous material with an engine-driven rotor, the element being attachable to the rotor shell conveniently at least one surface of revolution inclined to the rotor axis or extending approximately normally thereto and provided with crushing or grinding elements with a diameter increasing away from the material feed as well as optionally if at least two surfaces of, revolution inclined to the rotor axis or extending approximately normally thereto and having comminuting elements or the like are provided, some of them of opposing inclination to the rotor axis channels or bores for the …
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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 February 1, 1990 and granted August 3, 1993. A Canadian patent filed from October 1, 1989 lasts 20 years from filing, so its term ended February 1, 2010.
- A certificate of supplementary protection adds at most two years for a drug, so even that would have ended by February 1, 2012.
- 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.