A vacuum apparatus having textured web-facing surface for controlling the rate of application of vacuum pressure in a through air drying papermaking process
CA 2214235 C · Owner: The Procter & Gamble Company · Inventors: Ensign, Donald Eugene; Trokhan, Paul Dennis
Overview
Its claims, description and drawings are in the Canadian Patents Database.
Open the CIPO recordAbstract From the Canadian patent
A papermaking vacuum apparatus having a web-facing surface adapted to support a papermaking belt and comprising a head a body and at least one vacuumslot disposed in the head and defining an aperture on the web-facing surface. The vacuum slot is in fluid communication with the web-facing surface and extends from the web-facing surface to the body which is in further fluid communication with a vacuum source. The web-facing surface comprises a textured area in the region ofthe web-facing surface juxtaposed with the aperture defined by the vacuum slot. This textured area creates a leakage of at least about 35 Marlatts at a pressuredifferential of 7 inches of Mercury. This leakage eliminates …
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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 August 29, 1997 and granted May 16, 2000. A Canadian patent filed from October 1, 1989 lasts 20 years from filing, so its term ended August 29, 2017.
- A certificate of supplementary protection adds at most two years for a drug, so even that would have ended by August 29, 2019.
- 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.