Forging punch
CA 2023655 C · Owner: Asai, Tomohito · Inventors: Isono, Toru; Asai, Tomohito
Overview
Its claims, description and drawings are in the Canadian Patents Database.
Open the CIPO recordAbstract From the Canadian patent
A forging punch of the present invention includes: an outer punch of a cylindrical shape; and an inner punch disposed in the outer punch and protruding from an end surface of the outer punch; at least one of the punches having at least one groove for relieving oil formed either on an inner peripheral surface of the outer punch or on an outer peripheral surface of the inner punch. Therefore, an oil remaining between the end surface of the outer punch and the bottom surface of a workpiece is relieved to the outside of the forging punch by way of the groove, thereby enabling precise forging. Further, the forging punch has obviated additional processing, because no traces of the groove are …
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 August 20, 1990 and granted May 18, 1993. A Canadian patent filed from October 1, 1989 lasts 20 years from filing, so its term ended August 20, 2010.
- A certificate of supplementary protection adds at most two years for a drug, so even that would have ended by August 20, 2012.
- 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.