Device for operating discharge lamps
AssigneePatent-Treuhand-Gesellschaft fur elektrische Gluhlampen mbH
InventorsBernd Rudolph, Harald Schmitt
Life of this patent
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Abstract
A device for operating a plurality of discharge lamps (71, 72) is to be fashioned cost effectively. Two lamps (71, 72) are therefore operated in a single load circuit. In the preheating phase, the incandescent filaments (711, 712, 721, 722) are supplied with preheating current either directly or via a transformer (Ls, Lp). The preheating current is controlled via a temperature-dependent resistor (PTC) in such a way that the continuous heating current is greatly reduced over all the filaments during the operation of the lamp.
Claims7
A device for operating at least two discharge lamps (71, 72), having
- a first contact device for electrically connecting a first discharge lamp (71), which has two first incandescent filaments (711, 712),
- a second contact device for electrically connecting a second discharge lamp, which has two second incandescent filaments (721, 722), and
- a current control device for controlling the current through the two first and two second incandescent filaments (711, 712, 721, 722), characterized
- in that terminals (22, 23) of the first contact device for one of the first incandescent filaments (712) are connected to terminals (24, 25) of the second contact device for one of the second incandescent filaments (721) together with a secondary winding (Ls) of a transformer device in the circuit, and
- in that one terminal (21, 27), each of the first and second contact device for the respective other one of the first and second incandescent filaments (711, 722) are interconnected, with the interposition of the current control device (9), in series with the primary winding (Lp) of the transformer device.
Dependencies are inferred from the claim text.