Title:
DEVICE FOR LIGHTING FILAMENT LAMP
Document Type and Number:
WIPO Patent Application WO/2000/019777
Kind Code:
A1
Abstract:
A device for lighting and dimming a plurality of filament lamps are provided which eliminates the effects of harmonic distortion on its power supply. Lamp control circuits (1-1 to 1-n) are provided corresponding to filament lamps (4-1 to 4-n). The lamp control circuits (1-1 to 1-n) supply current to the filament lamps (4-1 to 4-n) when switching elements are on, while it allows the energy stored in inductors (L) to energize the filament lamps when the switching elements are off. The on/off operation is repeated so as to supply current of substantially the same waveform as the input current. A control section (3) controls the current for varying the duty factor of the on/off signal to the switching elements and also supplies the lamp control circuits (1-1 to 1-n) with the on/off signal with deviated timing.
Inventors:
KANNO TAKAYUKI (JP)
Application Number:
PCT/JP1999/005186
Publication Date:
April 06, 2000
Filing Date:
September 22, 1999
Export Citation:
Assignee:
USHIO ELECTRIC INC (JP)
KANNO TAKAYUKI (JP)
KANNO TAKAYUKI (JP)
International Classes:
H05B39/04; H05B37/02; (IPC1-7): H05B37/02
Foreign References:
| JPH0266889A | 1990-03-06 | |||
| JPH04126393A | 1992-04-27 | |||
| JPH08162257A | 1996-06-21 | |||
| JPH08172770A | 1996-07-02 |
Other References:
See also references of EP 1058485A4
Attorney, Agent or Firm:
Isohata, Masao (Asahitokai Building 6-1 Otemachi 2-chome Chiyoda-ku, Tokyo, JP)
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