Knife sharpening apparatus
CA 2005836 C · Owner: Friel, Daniel D. · Inventors: Friel, Daniel D.
Overview
Its claims, description and drawings are in the Canadian Patents Database.
Open the CIPO recordAbstract From the Canadian patent
A knife sharpening apparatus includes a moving abrasive surface. A magnetic guide has a guide surface in a plane disposed at a predetermined angle which intersects the plane of the abrasive surface. The magnetic guide is made from a magnetized material having opposite polarity north and south magnetic pole, faces with a first ferromagnetic member located against one pole and a second non-planar ferromagnetic member located in part against the other pole and a part extending parallel to the guide surface and contiguous to the magnetized material. The second ferromagnetic member is located at the surface remote from the abrasive 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
- Filed December 18, 1989 and granted March 28, 2000. A Canadian patent filed from October 1, 1989 lasts 20 years from filing, so its term ended December 18, 2009.
- A certificate of supplementary protection adds at most two years for a drug, so even that would have ended by December 18, 2011.
- 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.