Patent Yard Sign in
Expired Canadian patentCanada

Power circuit for transferring energy by alternately switching winding circuits of a transformer at high speed

CA 2238915 C · Owner: Nec Infrontia Corporation · Inventors: Hisanaga, Koji

CIPO record

Overview

Drawings and full text

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

Open the CIPO record

Abstract From the Canadian patent

In a power supply unit, AC energy is converted to DC energy and stored into a first capacitor to which a first winding of a transformer is connected. An anti-parallel circuit of a first transistor and a diode is connected between the first capacitor and the first winding. An anti-parallel circuit of a second transistor and a diode is connected between a second winding of the transformer and a second battery-charging capacitor. A, current is induced in a third winding of the transformer for charging a third capacitor when a current is produced in the first winding in a particular direction or when energy stored in the second winding is released into the third winding. The first and second …

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 May 28, 1998 and granted September 26, 2000. A Canadian patent filed from October 1, 1989 lasts 20 years from filing, so its term ended May 28, 2018.
  • A certificate of supplementary protection adds at most two years for a drug, so even that would have ended by May 28, 2020.
  • We check Canadian rights only. A patent in its family in another country could still be in force: check its family on Google Patents.
FiledMay 28, 1998
GrantedSeptember 26, 2000
Term endedMay 28, 2018
Patent numberCA 2238915 C
Classification (IPC)H02J9/06 +1 more

Timeline

Timeline From CIPO dates

1999200120032005200720092011201320152017Application filedMay 28, 1998Patent grantedSep 26, 2000Term endedMay 28, 2018

Sources & verification

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