Low pressure responsive downhole tool with hydraulic lockout
CA 2081083 A1 · Owner: Schultz, Roger L. · Inventors: Ringgenberg, Paul D.; Manke, Kevin R.; Schultz, Roger L.
Overview
Its claims, description and drawings are in the Canadian Patents Database.
Open the CIPO recordAbstract From the Canadian patent
An annulus pressure responsive well tool includes a selectively actuatable hydraulic bypass for bypassing a pressure differential across a power piston of the tool so that an operating element associated with the power piston will remain in a chosen position during a subsequent change in well annulus pressure.
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 October 21, 1992. No grant is recorded for it in Canada; had it been granted, its 20-year term would have ended October 21, 2012.
- A certificate of supplementary protection adds at most two years for a drug, so even that would have ended by October 21, 2014.
- 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.