| 摘要 |
PURPOSE:To attain a temperature control with high accuracy and to prevent a fire from taking place, by detecting overheat of all parts of heater wires for attaining a suitable temperature control, in a device warming seats of a car and a bed. CONSTITUTION:When the temperature of heater wires 10 of a tubing heater is lower than the set value, a resistance value of a heat-sensing member 9 is small, and when it is discriminated that the resistance value detected at a comparator 14 is smaller than the set value, a timer 21 is energized for applying power to the heater wires 10 and increasing the temperature to the set temperature. When the temperature of the heater wires 10 exceeds the set temperature or a part of the heater wires 10 is overheated, the comparator 14 detects the decrease in the resistance value of the heat-sensing member 9, the timer is stopped for energizing and the temperature of the heater wires 10 is decreased to the set temperature. |
