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Expired Canadian patentCanada

Hearing aid

CA 2069737 C · Owner: Ramstad, Tor Audun · Inventors: Svean, Jarle; Krokstad, Asbjorn; Ramstad, Tor Audun

CIPO record

Overview

Drawings and full text

Its claims, description and drawings are in the Canadian Patents Database.

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Abstract From the Canadian patent

Programmable hybrid hearing aid with digital signal processing comprising a main section (1) which can be inserted in the meatus (6). The main section (1) comprises an open connection between the ear opening and an inner portion of the meatus (6) providing an acoustic transmission channel with low-pass characteristic and resonant amplification. The main section further comprises an electroacoustic transmission channel based on digital signal processing and a signal processor (DSP) and with possibility for suppressing a possible acoustic signal feedback through the acoustic transmission channel. A variant of the hearing aid is provided with a microphone (M1) and the feedback signal is …

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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 November 29, 1990 and granted September 14, 1999. A Canadian patent filed from October 1, 1989 lasts 20 years from filing, so its term ended November 29, 2010.
  • A certificate of supplementary protection adds at most two years for a drug, so even that would have ended by November 29, 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.
FiledNovember 29, 1990
GrantedSeptember 14, 1999
Term endedNovember 29, 2010
Patent numberCA 2069737 C
Classification (IPC)H04R25/00 +1 more

Timeline

Timeline From CIPO dates

1991199319951997199920012003200520072009Application filedNov 29, 1990Patent grantedSep 14, 1999Term endedNov 29, 2010

Sources & verification

Everything on this page comes from the CIPO record linked above. Contains information licensed under the Open Government Licence – Canada.