Plunger and apparatus useful in extruding or dispensing viscous materials
CA 2203203 C · Owner: Beveridge, Keith A. · Inventors: Beveridge, Keith A.; Bennett, Mark A.; Waeber, Kenneth R.
Overview
Its claims, description and drawings are in the Canadian Patents Database.
Open the CIPO recordAbstract From the Canadian patent
The invention is a plunger useful in extruding or dispensing viscous material which comprises a thin disc of a material which is capable of deforming when, subjected to back pressure during use. The edge of the disc has a circular shape and a, cylindrical lip attached to the edge of the disc which lip is disposed , perpendicular to the edge of the disc. The disc has a face and a back surface located on opposite sides of, the sheet. The disc also has a symmetrical convex portion which protrudes beyond the, plane defined by the edge of the disc in the direction of the face and the peak of the, convex portion disposed in the center of the disc. The disc further comprises a, symmetrical …
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 April 21, 1997 and granted April 4, 2000. A Canadian patent filed from October 1, 1989 lasts 20 years from filing, so its term ended April 21, 2017.
- A certificate of supplementary protection adds at most two years for a drug, so even that would have ended by April 21, 2019.
- 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.