Digital transducer system
CA 2136760 C · Owner: Nicholson, Laurence R. · Inventors: Nicholson, Laurence R.; Tavis, John R.
Overview
Its claims, description and drawings are in the Canadian Patents Database.
Open the CIPO recordAbstract From the Canadian patent
A variable reluctance transducer system incorporating digital control of parallel resonant circuits (L1C1, L2C1) including two inductive sensors (L1, L2) on each side of a flat diaphragm. The two parallel resonant circuits provide dual frequency signals for digital calculation to obtain a quotient of the frequencies thereby , substantially eliminating the resonant frequencies as a variable in the accuracy of the device. Manipulation of the produced quotient by a microcontroller (10) employing digital calibration tables stored in a programmable read only memory (14) allows calibration responsive to a temperature sensor (16) thereby substantially , eliminating temperature induced error …
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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 May 17, 1993 and granted October 12, 1999. A Canadian patent filed from October 1, 1989 lasts 20 years from filing, so its term ended May 17, 2013.
- A certificate of supplementary protection adds at most two years for a drug, so even that would have ended by May 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.