Downhole gravity tool
CA 2247743 C · Owner: Wignall, Albert H. · Inventors: Wignall, Albert H.
Overview
Its claims, description and drawings are in the Canadian Patents Database.
Open the CIPO recordAbstract From the Canadian patent
A tool for conducting gravimetry survey downhole in an earth formation includes a pressure vessel which houses a gravity sensor that is supported by a gimbal. The gravity sensor is aligned with vertical before taking gravity measurements by a first stepper motor and a second stepper motor. The first stepper motor incrementally rotates the gimbal about the pivot axis of the gimbal while the second stepper motor incrementally rotates the gimbal about the longitudinal axis of the pressure vessel. The stepper motors are controlled by an electronic processor that responds to signals from an accelerometer assembly that measures the inclination of the pressure vessel with respect to vertical. An …
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 September 21, 1998 and granted July 24, 2001. A Canadian patent filed from October 1, 1989 lasts 20 years from filing, so its term ended September 21, 2018.
- A certificate of supplementary protection adds at most two years for a drug, so even that would have ended by September 21, 2020.
- 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.