An extruder screw having core portion of polygonal cross section
CA 1284414 C · Owner: Goodrich (B.F.) Company (The) · Inventors: Kim, Heung-Tai
Overview
Its claims, description and drawings are in the Canadian Patents Database.
Open the CIPO recordAbstract From the Canadian patent
A screw for use in an extruder barrel for plasticizing plastic material from a solid phase to a viscous form wherein the feed screw has a cylindrical core with a helical flight extending for the full length of the screw. A selected portion or portions of the screw's core has a polygonal cross section whose apexes are parallel to the axis of rotation of such screws to thereby more precisely control the plasticizing action of the plastic material its, viscosity and temperature while providing a thoroughly mixed and homogeneous melt.
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 May 28, 1991. A Canadian patent filed before October 1, 1989 lasted 17 years from grant, so its term ended May 28, 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.