| 摘要 |
<p>PURPOSE:To heat a liquid in a heater according to the required quantity of the liquid to thereby reduce the loss of heat radiation by a method wherein when it is detected from the signal of a temperature sensor on the side wall of the heater body that the quantity of the heated liquid in the heater is larger than a predetermined quantity, the heating resistor is not energized. CONSTITUTION:A heating resistor 5 is provided within a heater 1 having a liquid inlet port 3 and a liquid outlet port 2 and a linear or plane temperature sensor 4 for detecting the temperature of the liquid in the heater 1 is arranged vertically on the side wall of the heater 1 so as to extend uniformely along the side wall. Thus, when it is detected that the quantity of the heated liquid in the heater 1 is larger than the predetermined quantity, the heating resistor 5 is not energized so that the liquid in the heater 1 is prevented from being heated entirely at all times without regard to the required quantity of the liquid to be heated and it is possible to reduce the loss of heat radiation to thereby improve the conomical property of the heater.</p> |
