Multiple-Light Discharge Lamp Lighting Device

• US 20080211423A1
• Filed: 12/16/2005
• Published: 09/04/2008
• Est. Priority Date: 12/24/2004
• Status: Active Grant

• Current Assignee: Minebea Company Limited (MinebeaMitsumi Inc.)
• Original Assignee: Minebea Company Limited (MinebeaMitsumi Inc.)
• Inventors: Weger, Robert, Shinmen, Hiroshi
• Granted Patent: US 7,579,785 B2
• Time in Patent Office: Days
• US Class Current: 315/259
• CPC Class Codes: H05B 41/245 for a plurality of lamps
• CPC Class Codes: H05B 41/2827 using specially adapted components in the load circuit, e.g. feed-back transformers, piezoelectric transformers; using specially adapted load circuit configurations

Abstract

To provide a multiple-light discharge lamp lighting device that stabilizes and equalizes tube current of a plurality of discharge lamps without arranging a Ballast element to the secondary side of an inverter transformer with low costs. A multiple-light discharge lamp lighting device 10 according to the present invention includes inverter means 12 and a plurality of inverter transformers TR₁ to TR_n. Discharge lamps La₁ to La_n are connected to secondary windings Ns1 to Nsn of the inverter transformers TR₁ to TR_n. Preferably, variable impedance elements Z₁ to Z_n, as variable inductance elements, are serially connected to primary windings Np1 to Npn of the plurality of inverter transformers TR₁ to TR_n. Accordingly, the tube current can be stabilized and equalized without using an element resistant to a high voltage.

Claims

1. A multiple-light discharge lamp lighting device comprising inverter means that outputs a high-frequency voltage and a plurality of inverter transformers, the multiple-light discharge lamp lighting device lighting-on a plurality of discharge lamps connected to secondary windings of the plurality of inverter transformers,

wherein a variable inductance element as a ballast element is connected in series to each of primary windings of the plurality of the inverter transformers;

and

the variable inductance element is provided with a main winding and a control winding in such a manner that the main winding is connected to the primary winding of the inverter transformer, and the control winding has current signal input that corresponds to fluctuation of tube current flowing in the discharge lamps for variably controlling inductance value of the variable inductance element so as to stabilize the tube current flowing in the discharge lamps

2. The multiple-light discharge lamp lighting device according to claim 1, wherein a condenser is connected in parallel to each of the primary windings of the plurality of the inverter transformers.