×

Emergency lighting circuits

  • US 4,686,424 A
  • Filed: 01/21/1986
  • Issued: 08/11/1987
  • Est. Priority Date: 01/21/1986
  • Status: Expired due to Term
First Claim
Patent Images

1. An emergency lighting circuit for keeping a lamp energized in the absence of power line voltage comprisinga discharge lamp;

  • a high frequency inverter circuit having an input and an output;

    first circuit means for supplying power to said lamp from one of said output of said inverter circuit and said power lines supplying the line voltage;

    a normally closed contact set;

    a rechargeable battery connected to said input of said inverter circuit through said contact set; and

    a full wave rectifier, a ballast reactor and a relay winding connected in series circuit relationship with said battery across said power lines, said relay operating said contact set so that when line voltage is present said relay is energized and said battery is charged with said contact set open, energizing said lamp through said first circuit means from said power lines and so that failure of line voltage causes said relay to be deenergized, closing said contact set and resulting in inverter operation of said lamp.

View all claims
  • 2 Assignments
Timeline View
Assignment View
    ×
    ×