| 摘要 |
PURPOSE:To obtain a safety appliance for electric apparatuses, capable of breaking a power supply for a heater even in the state of a CPU be coming uncontrollable, by releasing a relay contact when a thermal switch senses the abnormality of temperature, and by breaking the power supply fed to the heater itself, and further, by informing a host device of a failure position as an alarm signal. CONSTITUTION:When in a heater 1, a failure is generated and a temperature is increased, a thermal switch 8 is operated and its sensed signal is inputted to a control part 4. An alarm signal is outputted from the control part 4 to a host device 6, and is displayed. The host device 6 can break a power supply 7 for the heater 1, responding to the alarm signal. But, before the timing of the alarm signal being inputted to the host device 6, a relay contact 5 of the power supply for the heater is opened directly by the thermal switch 8, utilizing the sensed signal, and the feed of the power supply to the heater is stopped. Thereby, even when a CPU in the control part 4 runs away, there is no possibility of the runaway and burning of a driving part, which are dangerous electrically and mechanically. Therefore, there is an effect in the aspect of safety. |
