| 摘要 |
<p>PURPOSE:To equalize specifications of a dimmer, and set it applicable to a capacity of a lighting load by providing a time sharing change control part to actuate the dimmers cyclicly in order for every half cycle of an AC power supplied to the lighting load. CONSTITUTION:On-zones of a photo-MOS 41 of a time sharing change control part 4 are changed in such a way that triacs 11 provided at three dimmers A-C are time-sharingly ignited for every half cycle of voltage waveforms of an AC power supply 3 applied to a lighting load 2. Shift pulses are sent by a power supply synchronism circuit 43 to a shift register 42, plural photo-MOS's 41 are selectively put on for every half wave of an AC voltage to drive the dimmers A-C for igniting the triac 11 in the dimmers 1. Ignition action is therefore performed for 1/3 duty compared to a case of a single dimmer for one triac 11. As a result, the dimmer can be formed as modules of the same specifications, and by adjusting the number of the dimmers combined with each other, to cope with a load from a small capacity to a large capacity.</p> |
