| 摘要 |
PURPOSE:To make it possible to control the temperature of an air flow to a predetermined value even the titled apparatus is in an abnormally used state where a suction port and a discharge port are blocked by connecting in series other PTC thermistors to a variable resistor of a hot air flow apparatus such as a hair drier or the like. CONSTITUTION:In a case where the ratio of a suction port 14 and a discharge port being blocked is small and an air flow quantity if not varied so much, an ignition angle in the positive one-half cycle of a heater 3a becomes large by the effect of a PTC thermistor 7a, the heater power is reduced, and the air flow temperature is controlled to a predetermined value, when the ratio of blocking the suction port and the discharge port is more than the half and the air flow quantity is less than the half, it is required to set the heater power to less than the half. However, the ignition angle in the positive semicycle of the heater 3a becomes large by the effect of a PTC thermistor 7c, and heater power becomes small and the temperature of the air flow is controlled to a predetermined value. In this case, the ignition angle in the negative one-half cycle of a motor 3b becomes large, and the rotational speed of the motor 3b is decreased. This makes the operator know an abnormal use is taking place.
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