Pencil sharpener
CA 2338196 C · Owner: Penshar, Llc · Inventors: Donaldson, Joseph K.
Overview
Its claims, description and drawings are in the Canadian Patents Database.
Open the CIPO recordAbstract From the Canadian patent
There is described herein a sharpener for a carpenter's pencil having a centering collar (14) mounted to a base enclosure (12) for relative rotation to generate the sharpening effect. Within the base enclosure (12) there is a symmetrical pencil point contour surface (22) and a blade (26;40) mounted along the contour surface (22) for cutting against the inserted pencil. The shape of the blade (26;40) is either curved or formed from a plurality of sections (42,44) to produce a narrow cut around the point extremity of the pencil and a wider cut further up the pencil shaft.
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 March 10, 2000 and granted October 21, 2003. A Canadian patent filed from October 1, 1989 lasts 20 years from filing, so its term ended March 10, 2020.
- A certificate of supplementary protection adds at most two years for a drug, so even that would have ended by March 10, 2022.
- 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.