Roll for guiding web type material
CA 2006255 C · Owner: Drefs, Wolfgang · Inventors: Ruff, Hans-Albrecht; Drefs, Wolfgang; Kuhn, Friedrich
Overview
Its claims, description and drawings are in the Canadian Patents Database.
Open the CIPO recordAbstract From the Canadian patent
A roll for guidance of web type material such as paper or, cardboard, has a shell that features a multitude of bores. The roll is coordinated with a device for subjecting the roll interior to suction. To hold the web on the roll at standstill part of these bores can be subjected to suction. In the operation of the roll, air trapped between the web and the roll shell can enter the roll also through the remaining bores and escape in the roll area that is not looped by the web.
Read the whole patent
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 December 20, 1989 and granted December 6, 1994. A Canadian patent filed from October 1, 1989 lasts 20 years from filing, so its term ended December 20, 2009.
- A certificate of supplementary protection adds at most two years for a drug, so even that would have ended by December 20, 2011.
- 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.