Patent · US Expired

Operating device for discharge lamps having a preheating device

US6753659B2 · kind B2 · utility

1Cited by

6References

5Claims

0Family size

Assignee

Patent-Treuhand-Gesellschaft fur elektrische Gluhlampen mbH · DE

Inventors

Olaf Busse · Munich, DE
Bernhard Schemmel · Weßling, DE
Michael Weirich · Unterhaching, DE

Key dates

Filing date	Dec 20, 2002
Grant date	Jun 22, 2004
Priority date	—
Expiry date	Dec 20, 2022

Classification

Technology area (CPC Y)Emerging Cross-Sectional Technologies
CPC primaryY10S315/07
WIPO fieldElectrical machinery, apparatus, energy
WIPO sectorElectrical engineering

Abstract

An operating circuit for a discharge lamp (LP) having preheatable electrodes includes a device (C14, T11, T12, T13, G) for preheating the electrodes. The device includes a resonant circuit (C14, T11) which oscillates during preheating. During operation, the operating circuit produces an AC voltage having a frequency that is moved through a frequency range, records the response of the resonant circuit (C14, T11) by measuring an electrical variable (UC14), and identifies the resonant frequency of the resonant circuit (C14, T11) from the electrical variable (UC14), and preheats the electrodes by setting the frequency of the AC voltage to the resonant frequency.

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