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Expired European patentEurope

Protection circuit for detachable operating unit used in audio device

EP 0448864 B1 · Applicant: PIONEER ELECTRONIC CORPORATION

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Overview

The published document from the EPO: abstract, claims, description and drawings. Open it full size

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Listed from its EPO record in Patent Yard's archive of European patents past their term. Its claims, description and drawings are in the EPO PDF and on Google Patents, and the Claude kit works from them.

Why it's free to use

  • Filed October 30, 1990 and granted December 20, 1995. A European patent lasts at most 20 years from filing, so its term ended October 30, 2010.
  • A supplementary protection certificate, which can extend a medicine or crop-protection patent, adds at most five and a half years, so even that would have ended by April 30, 2016.
  • We check European rights only. A US or other national patent in its family could still be in force: check its family on Espacenet or Google Patents.
FiledOctober 30, 1990
PublishedOctober 2, 1991
GrantedDecember 20, 1995
Term endedOctober 30, 2010
Application numberEP 90311879
Classification (CPC)H02H9/004

Timeline

Timeline From EPO dates

1991199319951997199920012003200520072009Application filedOct 30, 1990PublishedOct 2, 1991Patent grantedDec 20, 1995Term endedOct 30, 2010

Sources & verification