Carbon commutator
CA 2289419 C · Owner: Sakaura, Yoichi · Inventors: Yoshikawa, Noboru; Hotta, Tokio; Sakaura, Yoichi
Overview
Its claims, description and drawings are in the Canadian Patents Database.
Open the CIPO recordAbstract From the Canadian patent
Disclosed is a carbon commutator, comprising a plurality of metal segments each having a through-hole, a plurality of carbon segments each having a projecting portion, which contains a metal being inserted into the through-hole to be deformed so as to join tree carbon segment to the metal segment and a commutator body on which a plurality of the metal/carbon joined segments are arranged fixedly in a manner to form a substantially circular body.
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 November 12, 1999 and granted September 9, 2003. A Canadian patent filed from October 1, 1989 lasts 20 years from filing, so its term ended November 12, 2019.
- A certificate of supplementary protection adds at most two years for a drug, so even that would have ended by November 12, 2021.
- 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.