Extruder having spiral groove in barrel
CA 1048720 A · Owner: Sterling Extruder Corporation · Inventors: Fields, Reuben T.
Overview
Its claims, description and drawings are in the Canadian Patents Database.
Open the CIPO recordAbstract From the Canadian patent
An improvement for apparatus used for the extrusion of plastic resins comprising a screw element which operates rotatably within a close-fitting barrel having cut into the interior surface thereof a shallow and narrow groove of the same hand and substantially the same lead as the screw element. - 1 -
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 February 20, 1979. A Canadian patent filed before October 1, 1989 lasted 17 years from grant, so its term ended February 20, 1996.
- 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.