Acoustic apparatus
CA 2022002 C · Owner: Gen Engineering Co. Ltd. · Inventors: Ono, Hiroshi
Overview
Its claims, description and drawings are in the Canadian Patents Database.
Open the CIPO recordAbstract From the Canadian patent
An acoustic apparatus adapted to be heard only by a specific person or persons in one space without being worn by the user as in the case of an earphone. Sounds issuing from the apparatus do not leak to the outside and are not affected by the surrounding noise. Basically the apparatus, is arranged such that a sound source is disposed in one focus of a reflector having an ellipsoidal surface of revolution, and sounds are heard at the other focus. To increase the number of specific hearers if the central, portion of the reflector is made into a non-ellipsoidal surface of revolution, or a cross section having an ellipsoidal surface of revolution is extended orthogonally to the cross section by …
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 July 26, 1990 and granted October 5, 1999. A Canadian patent filed from October 1, 1989 lasts 20 years from filing, so its term ended July 26, 2010.
- A certificate of supplementary protection adds at most two years for a drug, so even that would have ended by July 26, 2012.
- 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.