| 摘要 |
PURPOSE:To enable to use a motor driven blower commonly as it is even if the power source cycle is different by setting a reference voltage of a reference voltage generator by selectively switching a resistor in response to the two types of the power source frequencies by a switch. CONSTITUTION:A motor driven blower 8 of an electric cleaner is connected to 50/60Hz 100V AC power source 7 through a bidirectional thyristor 9. The voltages of a capacitor C9 for starting charging by the output of a circuit 17 for detecting the zero cross of a power source and varying the charging period via a variable resistor VR1 and a reference voltage generator 13 are compared to control the thyristor 9. At this time, two resistors VR2, VR3 in response to the two types of the power source frequencies and a switch 18 are provided in the generator 13, and selectively switched according to 50Hz, 60Hz. Accordingly, even if the power source frequency is different, it can be used in an adequate state, and the irregular width of regulation can be narrowed. |
