Patent ID: 7245085
Filing Date: 2007-07-17
Classification: H05B

Abstract:
1. A means for restoring the continuity of a series connected, filament lamp circuit after one lamp filament opens, comprising: a plurality of series connected, filament lamps; a control relay in parallel with each of said lamps, the contacts of said relay being normally open when all lamps are burning; a power resistor in series with the contacts of each said relay, said power resistor arranged to provide a resistive load that is substantially the same as that of a lamp filament; and a second resistor in series with each of said control relays, the resistance value of said second resistor set so that said control relay will not pick up and close said contacts when all lamps in said circuit are functional, but will pick up when a lamp filament opens and imposes a high voltage across said second resistor to thereby substitute said power resistor for said opened lamp filament and restore the continuity of the circuit.