Global Patent Index - EP 0893943 A1

EP 0893943 A1 19990127 - Inverter for a gas discharge lamp with stepwise variable frequencies

Title (en)

Inverter for a gas discharge lamp with stepwise variable frequencies

Title (de)

Wechselrichter zur Versorgung einer Entladungslampe mit sprunghaft veränderlicher Frequenz

Title (fr)

Onduleur à fréquence graduellement variable pour alimenter une lampe à décharge

Publication

EP 0893943 A1 19990127 (EN)

Application

EP 97202310 A 19970724

Priority

EP 97202310 A 19970724

Abstract (en)

The invention relates to an inverter for feeding a gas discharge lamp, comprising: a direct voltage source; at least two switch elements incorporated in a bridge circuit; a control circuit for controlling the switch elements so that the bridge circuit continuously generates an alternating voltage; at least one ballast inductance connected to one of the output terminals of the bridge circuit; and at least one gas discharge lamp connected between the ballast inductance and the other output terminal of the bridge circuit, wherein the control circuit is adapted to apply at its output terminals a control signal to the switch elements of the bridge circuit so that the alternating voltage generated by the bridge circuit changes frequency stepwise in time between at least three frequencies. According to a preferred embodiment the time duration for which a signal of a determined frequency is generated depends on the value of the frequency. <IMAGE>

IPC 1-7

H05B 41/392

IPC 8 full level

H05B 41/292 (2006.01)

CPC (source: EP)

H05B 41/2928 (2013.01)

Citation (search report)

Designated contracting state (EPC)

AT BE DE ES FI FR GB IE IT NL SE

DOCDB simple family (publication)

EP 0893943 A1 19990127; EP 0893943 B1 20060215; AT E318068 T1 20060315; DE 69735257 D1 20060420; DE 69735257 T2 20061116

DOCDB simple family (application)

EP 97202310 A 19970724; AT 97202310 T 19970724; DE 69735257 T 19970724