Pressure change signals for remote control of downhole tools
CA 2111735 C · Owner: Schultz, Roger Lynn · Inventors: Skinner, Neal Gregory; Schultz, Roger Lynn; Kyle, Donald G.
Overview
Its claims, description and drawings are in the Canadian Patents Database.
Open the CIPO recordAbstract From the Canadian patent
Methods of controlling a downhole tool in a well are disclosed wherein pressure change signals are introduced into a column of fluid standing in the well. The command signal includes at least one high level pressure change applied to the column of fluid. The high level pressure change includes a change from a first value to a second value with the second, value being at least about 1,000 psi above hydrostatic pressure of the column of fluid in the well, and with pressure being maintained at the second value for an interval of time corresponding to information stored in a control system of the downhole valve. A number of suitable command signal formats are disclosed, particularly including …
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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 December 17, 1993 and granted February 13, 2001. A Canadian patent filed from October 1, 1989 lasts 20 years from filing, so its term ended December 17, 2013.
- A certificate of supplementary protection adds at most two years for a drug, so even that would have ended by December 17, 2015.
- 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.