Means for mounting a roller cutter on a drill bit
CA 2033701 C · Owner: Schlumberger Technology Corporation · Inventors: Pearce, David E.; Walter, James C.
Overview
Its claims, description and drawings are in the Canadian Patents Database.
Open the CIPO recordAbstract From the Canadian patent
A rotary drill bit (10) having a roller cutter (28) retained on a journal (24) by an externally threaded retainer ring (52) mounted within an annular groove (48) in the journal (24). The radii (R1, R2) formed at the inner and outer corners of the groove (48) are designed by suitable formulas to provide adequate strength for the journal (24) including the flange (50) adjacent the groove (48).
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 January 7, 1991 and granted February 27, 1996. A Canadian patent filed from October 1, 1989 lasts 20 years from filing, so its term ended January 7, 2011.
- A certificate of supplementary protection adds at most two years for a drug, so even that would have ended by January 7, 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.