Expansion assembly for mine roof bolts utilized in small diameter bore holes
CA 2019045 A1 · Owner: Jennmar Corporation · Inventors: Stankus, John C.; Cokus, Michael A.; Yacisin, Paul
Overview
Its claims, description and drawings are in the Canadian Patents Database.
Open the CIPO recordAbstract From the Canadian patent
An improved expansion assembly for a mine roof bolt for use in a nominal one inch diameter bore hole with a nominal 5/8" diameter roof bolt is provided. The expansion assembly has a tapered plug with four tapered surfaces, an expansion shell that has four leaves extending axially upwardly from a support ring and into contact with the four tapered surfaces on the tapered plug, and a threaded support washer to support the expansion shell on the threaded end of a mine roof bolt. The tapered plug has a threaded bore therethrough for threading onto the mine roof bolt. The tapered plug tapered surfaces have an angle of taper of at least 6.5° to the axis of the mine roof bolt. The expansion leaves …
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 June 14, 1990. No grant is recorded for it in Canada; had it been granted, its 20-year term would have ended June 14, 2010.
- A certificate of supplementary protection adds at most two years for a drug, so even that would have ended by June 14, 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.