Bearings for roller cutter assembly
CA 2043781 A1 · Owner: White, Kenneth M. · Inventors: White, Kenneth M.
Overview
Its claims, description and drawings are in the Canadian Patents Database.
Open the CIPO recordAbstract From the Canadian patent
A roller cutter assembly for a roller reamer which can be attached to a drill string is formed of a cylindrical body having an integral tapered bearing pin at each end. A journal bearing block for each bearing pin can be secured to the roller reamer by welding so as to hold the cutter rotatably on the reamer. The bearing block has a diameter slightly larger than that of the bearing pin. The angle of taper of the bearing pins and bearing surfaces is greater than the arc tangent of the coefficient of static friction between the coacting bearing surfaces such that the bearing pins do not self lock in the bearing blocks.
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 3, 1991. No grant is recorded for it in Canada; had it been granted, its 20-year term would have ended June 3, 2011.
- A certificate of supplementary protection adds at most two years for a drug, so even that would have ended by June 3, 2013.
- 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.