| 摘要 |
PURPOSE:To eliminate an electric shock accident and at the same time to attain miniaturization of the titled control circuit, by using a tripod transformer to insulate an operation switch and a variable resistor from a power supply. CONSTITUTION:A variable resistor 12 and a switch 13 are connected in series to both terminals of a secondary coil 7 of a tripod transformer 1. At the same time, a primary coil 6 and a series circuit of a full wave rectifier 14, a resistance 15 and a capacitor 16 are connected in parallel to a power supply 17. While a full wave rectifier 18 is connected to both terminals of a third coil 8. A capacitor 19 for pulse absorption is put into the DC side of the rectifier 18, and the DC output is divided and applied between the base and the emitter of a transistor 20 connected to the DC side of the rectifier 14 via resistances 21 and 22. Then the juncture of the resistance 15 and the capacitor 16 is connected via an SBS25 to the gate of a triac 24 which is set in series to a load 23 connected to the power supply 17. The charging time of the capacitor 16 is delayed by varying the resistor 12. Thus the phase control is made possible for the load electric power. |
