| 摘要 |
PURPOSE:To discharge rapidly high voltage generated on the high voltage ends of lamps even if at least a single lamp cannot be lighted normally, and downsize electric power supply by arranging a protective circuit such as a resistance or two Zener diodes on the high voltage end sides of plural fluorescent lamps. CONSTITUTION:Both two fluorescent lamps 1 and 2 are connected to the secondary side coil of a transformer 4 through a connector 3 and capacitors C1 and C2. One end of P1 of the capacitor C1 is connected to the high voltage end of the lamp 1, and one end P2 of the capacitor C2 is connected to the high voltage end of the lamp 2, respectively, and a resistence 5 being a protective circuit is arranged between the high voltage ends 1 and P2. By constituting in this way, when electric power supply is closed, though voltage of about 1200V is generated between the respective P1 and P2 and the earth by operation of the transformer 4, as for the P1, the lamp 1 operates normally, and voltage is reduced to about 400V, and as for the P2, since the lamp 2 is put in a normal lighting impossible condition, the electric charge of the P2 is discharged through the resistance 5 and the lamp 1, and the voltage of the P2 is put in the same as the voltage of the P1. |
