Patent · US Expired

High-voltage transformer protection circuit

US5119262A · kind A · utility

5Cited by
3References
10Claims
0Family size

Assignee

Inventor

Key dates

Filing dateJul 26, 1989
Grant dateJun 2, 1992
Priority date
Expiry dateJul 26, 2009

Classification

  • Technology area (CPC H)Electricity
  • CPC primaryH04N3/20
  • WIPO fieldAudio-visual technology
  • WIPO sectorElectrical engineering

Abstract

A protection circuit against an excessive current in a flyback transformer which supplies a high voltage to a CRT. A fuse and current detecting resistor are inserted on the line which supplies a current to the primary winding of the flyback transformer. The intermediate point of the primary winding and the node of the fuse and current detecting resistor are connected by a semiconductor switching element which becomes conductive when the voltage across the current detecting resistor reaches a certain high voltage. Accordingly, if an excessive current flows in the flyback transformer, the thyristor turns on, causing the fuse to be blown by the large current, whereby the current supply to the flyback transformer can be shut off.

Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.