Rock bolt shell and cone
CA 2122945 C · Owner: Wilkinson, John Christian · Inventors: Wilkinson, John Christian
Overview
Its claims, description and drawings are in the Canadian Patents Database.
Open the CIPO recordAbstract From the Canadian patent
A rock bolt shell and cone. An expansible shell having a cylindrical outer surface and raised ridges in relief on the exterior of the shell. One or more ridges are located along a curve non-congruent with a circumferential circle of the cylinder. In a disclosed embodiment each ridge lies along a helix of the cylinder and ridges are paired such that the helix of a first extends in one rotational direction while the curve of a second of the pair extends in the other rotational direction. each helix forms an angle of forty-five degrees with a centre line of the cylinder. Ridges intersect such that "V"-shaped projections extend along the outside of the shell. The vertices of certain of the …
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 May 5, 1994 and granted June 10, 2003. A Canadian patent filed from October 1, 1989 lasts 20 years from filing, so its term ended May 5, 2014.
- A certificate of supplementary protection adds at most two years for a drug, so even that would have ended by May 5, 2016.
- 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.