Improved electromagnetic hearing system
CA 2118815 C · Owner: Buchele, William · Inventors: Buchele, William
Overview
Its claims, description and drawings are in the Canadian Patents Database.
Open the CIPO recordAbstract From the Canadian patent
The present invention comprises a hearing system apparatus and method for electromagnetically communicating signals to a magnetic transducer. The apparatus includes a signalling circuit (10 30, 40) for producing a pulse-width modulated current signal. An antenna means (60) is coupled to the signalling circuit (10 30, 40) for producing a variable electromagnetic field whose energy intensity is modulated by the output of the signalling circuit. In addition an energy storage circuit (160) is coupled to the antenna (60) for storing a substantial portion of the energy stored in the magnetic field produced by the antenna (60) when the magnetic field collapses between cycles of the current signal. …
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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 July 23, 1992 and granted April 21, 1998. A Canadian patent filed from October 1, 1989 lasts 20 years from filing, so its term ended July 23, 2012.
- A certificate of supplementary protection adds at most two years for a drug, so even that would have ended by July 23, 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.