| 摘要 |
<p>Automatic coffee machines have very low thermal efficiency because they have to heat a considerable thermal mass, constituted by the heater 3) appearing in FIG. 1, which has a weight generally ranging between 0.5 and 1 Kg of metal, typically consisting of aluminium. Said mass is used to stabilise the temperature of the water to be injected in the blend of coffee. In this configuration, 90% or more of the thermal energy is wasted. The energy saving coffee machine, the subject matter of the present invention, is instead constructed with a heater 3), appearing in FIG. 4, that has a thermal mass much lower than the mass of the liquid to be heated, and is typically constructed with metal tube 30), as shown in FIG. 4, weighing a few grams. The heating current 41) in FIG. 4 flows directly on said tube, heating it together with the water contained therein, while a very rapid temperature control circuit makes it possible to maintain a constant temperature of the water flowing through the heater 3) shown in FIG. 4. Temperature measurement is carried out by monitoring the resistance of the tube 30) shown in FIG. 4, at the times in which the heating current 41) is not passing through the latter. In this manner, high energy efficiency is obtained, in that the dispensing of the coffee begins immediately upon pressing the start push button 48) and the machine is kept completely switched off between the dispensing of one cup of coffee and the next.</p> |
