Energizing circuits for fluorescent lamps
AssigneeElectrides Corporation
InventorFrank A. Summa
Life of this patent
Estimating the term…
Abstract
Apparatus is disclosed which may be utilized as an energizing circuit for the ignition of fluorescent lamps and other gas discharge luminescent devices. The circuit directs energizing signals to gaseous discharge tubes at a voltage sufficient to intitiate ionization of the gases therein. The signals are characterized by having a predetermined frequency in the range from about 20 kilohertz to 10 megahertz. Thereafter, the circuit lowers the voltage and current of the signal delivered to the tubes to a level sufficient to maintain gas ionization. Significant power savings are realized over conventional ballast circuits with the apparatus of the present invention.
Claims5
In a transformer-coupled oscillator circuit for generating a high frequency signal across the secondary of the transformer to energize flourescent tubes, said oscillator circuit including at least one transistor and a DC power source with first and second terminals, the improvement comprising:
- a ferromagnetic pot-core transformer having first and second primary windings and a secondary winding, said second primary winding coupled between the first terminal of the DC power source and the collector of each said transistor;
- a first parallel R-C circuit having one end thereof coupled to the base of each said transistor and the second end thereof coupled to the second terminal of the DC power source;
- a second parallel R-C circuit having one end thereof coupled to the base of each said transistor;
- a bias resistor coupled between the second ends of said first and second R-C circuits;
- a serial combination of a third parallel R-C circuit and the first primary winding, coupled between the first terminal of the DC power source and the second end of said second R-C circuit;
- and
- an emitter resistor coupled between the emitter of each said transistor and the second terminal of the DC power source.
Dependencies are inferred from the claim text.