Apparatus and process for forming center unwindable rolls of perforatedplastic film
CA 1282765 C · Owner: Roeland, James F. · Inventors: Gavin, James R.; Roeland, James F.
Overview
Its claims, description and drawings are in the Canadian Patents Database.
Open the CIPO recordAbstract From the Canadian patent
An apparatus and a method are disclosed for winding strips or tubes of plastic film into center-unwindable rolls having a diameter of at least about 3 inches and for unloading the wound rolls without telescoping thereof. Bare expandable winding shafts are provided which comprise a fixed vacuum leaf and a plurality of movable leaves controlled by an elongated air bladder the, contracted diameter being at least about one-quarter inch less than the expanded diameter. Each leaf also has an outer surface having a selected slipperiness toward the film surface.
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
- Granted April 9, 1991. A Canadian patent filed before October 1, 1989 lasted 17 years from grant, so its term ended April 9, 2008.
- 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.