Rockbolt
CA 2089609 C · Owner: Hollis, Ian · Inventors: Hollis, Ian
Overview
Its claims, description and drawings are in the Canadian Patents Database.
Open the CIPO recordAbstract From the Canadian patent
A rockbolt for anchoring in a borehole and then tensioning it has a nut at its proximal end whose screw threaded engagement with the rockbolt is utilised to force the nut against the surface at which the borehole is provided and cause tensioning of the rockbolt. Initially the nut cannot be run down the rockbolt owing to provision of a disc seated in a recess at the proximal end of the nut and which is only forced out from the recess when the nut is subject to a minimum predetermined torque. Holding of the disc in the recess is achieved by deformations of the nut resulting in the perimeter of the disc being frictionally restrained.
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 February 16, 1993 and granted May 5, 1998. A Canadian patent filed from October 1, 1989 lasts 20 years from filing, so its term ended February 16, 2013.
- A certificate of supplementary protection adds at most two years for a drug, so even that would have ended by February 16, 2015.
- 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.