Direct ink storing type writing instrument
CA 2223135 C · Owner: Mitsubishi Pencil Kabushiki Kaisha · Inventors: Matsumoto, Kazuaki
Overview
Its claims, description and drawings are in the Canadian Patents Database.
Open the CIPO recordAbstract From the Canadian patent
A longitudinal groove which allows a number of annular grooves formed on the outer peripheral surface of an ink storage body to communicate with an ink chamber is cut halfway into the thickness of a flange formed at the rear part of the ink storage body. An outer part of the longitudinal groove cut into the flange is made to communicate with a passage which is defined by a cutout formed on the periphery of the flange and the inner wall of the barrel cylinder so that this passage establishes communication between the longitudinal groove and the ink chamber.
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 24, 1996 and granted January 9, 2001. A Canadian patent filed from October 1, 1989 lasts 20 years from filing, so its term ended December 24, 2016.
- A certificate of supplementary protection adds at most two years for a drug, so even that would have ended by December 24, 2018.
- 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.