| 摘要 |
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. |
| 主权项 |
1. A machine for coffee or other infusions in boiling water, comprising:
a heater (3), comprising a tube (30) predisposed for being heated for the purpose of increasing the temperature of a flow of water, continuous or discontinuous, between an inlet (33) and an outlet (34); heating means (R) predisposed for utilising an electric current for the purpose of heating the tube (30); characterised in that it comprises: at least one temperature sensor (S) structured in such a manner as to be substantially at the same temperature as the tube (30) and to vary in resistance based on its own temperature; a controller (9), predisposed for commanding the delivery of an electric heating current to the heating means (R) and delivery of an electric measuring current to the temperature sensor (S); a processing block (40), predisposed for measuring the voltage present at the terminals of the temperature sensor (S), when the electric measuring current is passing through it, and for comparing the measured voltage with a known reference voltage (52), generating an error signal (51); a control circuit (9) is predisposed for commanding the delivery of an electric current to the heating means (R), said electric current being proportional to the error signal (51) received. |
