Patent · US Expired

Ballast for gas discharge lamps with shutdown of the filament heating

US6555970B2 · kind B2 · utility

3Cited by

1References

11Claims

0Family size

Assignee

Patent-Treuhand-Gesellschaft fur elektrische Gluhlampen mbH · DE

Inventors

Bernhard Schemmel · Weßling, DE
Michael Weirich · Unterhaching, DE

Key dates

Filing date	Jan 7, 2002
Grant date	Apr 29, 2003
Priority date	—
Expiry date	Jan 7, 2022

Classification

Technology area (CPC H)Electricity
CPC primaryH05B41/295
WIPO fieldElectrical machinery, apparatus, energy
WIPO sectorElectrical engineering

Abstract

An electronic ballast for discharge lamps with electrode filaments. The ballast contains a frequency-selective device, which suppresses an auxiliary heating current in the electrode filaments during operation of the lamp. Heating of the electrode filaments is possible only within a narrow frequency band.

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