Electrical sensor for sensing moisture in soils
CA 2093196 C · Owner: Hawkins, Alfred J. · Inventors: Hawkins, Alfred J.
Overview
Its claims, description and drawings are in the Canadian Patents Database.
Open the CIPO recordAbstract From the Canadian patent
A soil moisture sensor to be implanted in soil. The sensor has a conductive metal housing perforated to, pass moisture to and through a filter liner which lines an internal cavity. A transfer matrix is confined in the liner and is abutted by a buffer tablet of compacted gypsum. An electrode matrix abuts the tablet and bridges a pair of spaced-apart electrodes. Water, or absence of water in the, electrode matrix provides a measure of moisture in the soil as a function of electrical conductivity between the electrodes.
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 April 1, 1993 and granted December 16, 2003. A Canadian patent filed from October 1, 1989 lasts 20 years from filing, so its term ended April 1, 2013.
- A certificate of supplementary protection adds at most two years for a drug, so even that would have ended by April 1, 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.