Method and apparatus in the drying section of a paper making machine for speeding the threading of a paper or paperboard web
CA 2015344 C · Owner: Valmet Paper Machinery Inc. · Inventors: Vuorinen, Vesa; Virta, Raimo; Ruottu, Reijo
Overview
Its claims, description and drawings are in the Canadian Patents Database.
Open the CIPO recordAbstract From the Canadian patent
A method and apparatus in a drying section of a paper making machine wherein a so-called single-wire draw is applied and wherein blow boxes (20) are used, which are intended to prevent phenomena that disturb the mutual support contact between the web (W) and the drying wire (12). The blow boxes (20) extend across the entire width of the web (W), and they communicate with members (17, 18, 21, 22) that supply blow air, and they are provided with at least two nozzle slots (13, 14) transverse to the running and longitudinal direction of the web (W) as well as with a carrier face (16) between said nozzle slots. Negative pressure is produced in the space (A-) defined by the carrier face (16) and …
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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 April 30, 1990 and granted February 16, 1999. A Canadian patent filed from October 1, 1989 lasts 20 years from filing, so its term ended April 30, 2010.
- A certificate of supplementary protection adds at most two years for a drug, so even that would have ended by April 30, 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.
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Everything on this page comes from the CIPO record linked above. Contains information licensed under the Open Government Licence – Canada.