Ultra hard insert cutters for heel row rotary cone rock bit applications
CA 2125335 C · Owner: Smith International, Inc. · Inventors: Mcdonough, Scott D.; Siracki, Michael A.; Cawthorne, Chris E.
Overview
Its claims, description and drawings are in the Canadian Patents Database.
Open the CIPO recordAbstract From the Canadian patent
A rotary cone rock bit for drilling boreholes in an earthen formation is disclosed. One or more rotary cones are rotatably retained on a journal bearing connected to the rock bit. These rotary cones form a circumferential heel row with extended ultra hard shaped cutters spaced within the heel row. Each of the shaped cutters form a cutting surface that extends above the heel row or is angled with respect to the formation to maintain the cutters in compression while the cutters shear a borehole wall. The shaped cutters serve to maintain the borehole diameter.
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 7, 1994 and granted August 4, 1998. A Canadian patent filed from October 1, 1989 lasts 20 years from filing, so its term ended June 7, 2014.
- A certificate of supplementary protection adds at most two years for a drug, so even that would have ended by June 7, 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.