| 摘要 |
PURPOSE:To prevent heating efficiency from being lowered when the heating output is decreased, and thereby eliminate resistance for discharging as well as to contrive an reduction of parts in number by connecting a cooling fan motor with a filter capacitor in parallel. CONSTITUTION:A cooling fan motor 12 is connected with a filter capacitor 6 in parallel, and an inverter circuit 16 is connected with the filter capacitor 6 and the both ends of a TRIAC 11. The inverter circuit 16 is composed of a parallel circuit with a heating coil 8 and a commutation capacitor 9, a transistor 9 acting as a power switching element, and of a fly wheel device 10. When the inverter circuit 16 is suspended in oscillation, the TRIAC 11 is simultaneously turned off. In this case, the fan motor 12 is also suspended simultaneously, the loading of the filter capacitor 6 is concurrently discharged via the fan motor 12, thereby letting the loading vanish instantly. This constitution allows the fan motor to be rotated only during heating, thereby eliminating load in electricity, and also improving cooling effect as well as conversion efficiency considerably. |
