| 摘要 |
<p>An espresso coffee machine having a boiler provided with an electric resistance heater is fitted with a temperature transducer of the negative temperature coefficient (NTC) resistance type producing an output signal indicative of the boiler temperature. A comparator unit is fed the output signal and compares the signal with the extreme values of a temperature range to control activation and deactivation of the heater. A first display device fed by the output signal continuously displays the boiler water temperature. The output signal is also continuously fed to a memory and processing unit having stored therein the Mollier diagram curve relating to saturated vapor. The memory and processing unit continuously outputs the value of the corresponding water vapor pressure in the boiler, which value is displayed by a second display device.</p> |
