Acoustic heterodyne device and method
CA 2261108 C · Owner: American Technology Corporation · Inventors: Norris, Elwood G.
Overview
Its claims, description and drawings are in the Canadian Patents Database.
Open the CIPO recordAbstract From the Canadian patent
The present invention is the emission of new sonic or subsonic compression waves from a resonant cavity (80) as a result of interference of at least two ultrasonic wave trains (30, 32). In one embodiment two ultrasonic emitters , (20) are oriented toward the cavity. When the difference in frequency between the two ultrasonic wave trains is in the sonic or subsonic frequency range a , new sonic or subsonic wave train of that frequency is emitted from within the cavity or region of interference in accordance with the principles of acoustical heterodyning. The preferred embodiment is a system comprised of a single ultrasonic radiating element oriented toward the cavity emitting multiple …
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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 16, 1997 and granted October 14, 2003. A Canadian patent filed from October 1, 1989 lasts 20 years from filing, so its term ended July 16, 2017.
- A certificate of supplementary protection adds at most two years for a drug, so even that would have ended by July 16, 2019.
- 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
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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.