Trepanning tool
CA 2012678 C · Owner: Hamilton, Martin N. · Inventors: Hamilton, Martin N.
Overview
Its claims, description and drawings are in the Canadian Patents Database.
Open the CIPO recordAbstract From the Canadian patent
A trepanning tool having a hollow, cylindrical body having a central axis with a drive means on one end and a means supporting cutting inserts on the other end. The cutting inserts are arranged to cut in groups of three. Each insert has at least one generally straight cutting edge, the second insert of each said group being disposed generally perpendicular to the central insert the cutting, edge of the first and third insert each being disposed at an acute angle in a vertical plane to the cutting edge of the first insert whereby the three inserts cut a concave circular groove as the tool rotates.
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 21, 1990 and granted April 21, 1998. A Canadian patent filed from October 1, 1989 lasts 20 years from filing, so its term ended March 21, 2010.
- A certificate of supplementary protection adds at most two years for a drug, so even that would have ended by March 21, 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.