| 摘要 |
PURPOSE:To obtain safety control of a heater by providing a waterless boiling preventing control means which turns the heater OFF when a time period from turning-ON of the heater by a first temperature deciding means to turning-OFF of the heater by a second temperature deciding means is shorter than a prescribed value. CONSTITUTION:A controller 13 is provided with a first temperature deciding means 14 for comparing temperature signal from a temperature detector 12 with a first reference temperature signal, a second temperature deciding means 15 for comparing the temperature signal with a second reference temperature signal which is higher than the first reference temperature signal, and further with a warmth retaining control means 16 for turning a heater 3 ON when the temperature signal is lower than the first reference temperature signal in the first temperature deciding means 14 and turning the heater 3 OFF when the temperature signal is higher than the second reference temperature signal in the second temperature deciding means 15, and a waterless boiling preventing control means 17 for turning the heater OFF when a time period from turning-ON of the heater 3 by the first temperature deciding means 14 to turning- OFF of the heater by the second temperature deciding means 15 is shorter than a prescribed value. Thus, safety control of the heater can be obtained. |
