Air ring for cooling blown plastic film
CA 2246468 A1 · Owner: Planeta, Mirek · Inventors: Planeta, Mirek; Dang, Nghia (Paul) C.
Overview
Its claims, description and drawings are in the Canadian Patents Database.
Open the CIPO recordAbstract From the Canadian patent
An air ring for supplying cooling air to a hot extruded plastic film after the film has been extruded from an annular extrusion die at an elevated temperature has, an annular body which surrounds the tubular film after the film has left the extrusion die. The said body has a circumferentially extending air passage through, which air can be supplied from an external source and which directs cooling air from, the passage between the body and the film. A circumferentially extending series of, individually operable actuators are each operable to vary the flow of cooling air to, cause the film to become nearer to or further from the body at its circumferential, location to cause the …
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 September 3, 1998. No grant is recorded for it in Canada; had it been granted, its 20-year term would have ended September 3, 2018.
- A certificate of supplementary protection adds at most two years for a drug, so even that would have ended by September 3, 2020.
- 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.