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EP 0131633 B1 · Applicant: MATSUSHITA ELECTRIC INDUSTRIAL CO., LTD.

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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 January 13, 1984 and granted October 26, 1988. A European patent lasts at most 20 years from filing, so its term ended January 13, 2004.
  • 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 July 13, 2009.
  • 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.
FiledJanuary 13, 1984
PublishedJanuary 23, 1985
GrantedOctober 26, 1988
Term endedJanuary 13, 2004
Application numberEP 84900532
Classification (CPC)H03D9/0641 +1 more

Timeline

Timeline From EPO dates

1985198719891991199319951997199920012003Application filedJan 13, 1984PublishedJan 23, 1985Patent grantedOct 26, 1988Term endedJan 13, 2004

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