Ballast for a discharge lamp with adaptive preheating

US8134297B2 · kind B2 · utility

Assignee

• OSRAM GmbH · DE

Inventors

• Olaf Busse · Munich, DE
• Markus Heckmann · Munich, DE
• Reinhard Lecheler · Leibnizweg, DE
• Alfons Lechner · Pfaffenhofen an der Ilm, DE
• Siegfried Mayer · Leinfelden, DE
• Thomas Pollischansky · Stadtbergen, DE
• Bernd Rudolph · Forstern, DE
• Bernhard Schemmel · Weßling, DE
• Kay Schmidtmann · Birkenfeld, DE
• Harald Schmitt · Hersbruck, DE
• Thomas Siegmund · West Lafayette, US
• Arwed Storm · Dachau, DE
• Horst Werni · Birkenfeld, DE

Key dates

• Filing date: Aug 30, 2006
• Grant date: Mar 13, 2012
• Expiry date: Aug 26, 2028

Classification

• Technology area (CPC H): Electricity
• CPC primary: H05B41/295
• WIPO field: Electrical machinery, apparatus, energy
• WIPO sector: Electrical engineering

Abstract

The present invention relates to an electronic ballast for discharge lamps (LA) which have preheatable electrodes (E1, E2). The electronic ballast has a measuring apparatus (M), which is designed to measure, during the preheating process, a variable, which is correlated with the electrode temperature increased by the preheating, of at least one of the electrodes (E1, E2) of a connected discharge lamp (LA), and a control apparatus (C), which is designed to match the electrode temperature, during the preheating process, in response to the measurement by adjusting an operational parameter of the electronic ballast. Furthermore, the electronic ballast is designed to detect cross discharges or a sufficient operating temperature of one of the electrodes (E1, E2) and possibly to ignite the discharge.