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Expired Canadian patentCanada

Luminous tube protection circuit

CA 2030848 C · Owner: Pitre, John W. Jr. · Inventors: Pitre, John W. Jr.; Whorton, Jere D.

CIPO record

Overview

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

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Abstract From the Canadian patent

A protection circuit for monitoring the power from a luminous tube transformer to a luminous tube including sensor connected to a secondary of the transformer a window compar-, ator circuit connected to the sensor and providing a fault signal when the sensor output exceeds the window limits and a, driver switching off power to the transformer primary when the driver receives a fault signal. A temperature compensation circuit monitors the ambient air temperature for providing a time delay before disconnecting the power supply until the luminous tube stabilizes, and also turns off the power supply when the ambient temperature exceeds upper and lower limits.

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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 26, 1990 and granted June 25, 2002. A Canadian patent filed from October 1, 1989 lasts 20 years from filing, so its term ended November 26, 2010.
  • A certificate of supplementary protection adds at most two years for a drug, so even that would have ended by November 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.
FiledNovember 26, 1990
GrantedJune 25, 2002
Term endedNovember 26, 2010
Patent numberCA 2030848 C
Classification (IPC)H05B41/36 +2 more

Timeline

Timeline From CIPO dates

1991199319951997199920012003200520072009Application filedNov 26, 1990Patent grantedJune 25, 2002Term endedNov 26, 2010

Sources & verification

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