Abstract: Dishwashing machine including a washing tank (1) provided with an upper aperture (6) and a lower aperture (7) that are interconnected through a conduit (8) extending outside the tank. During drying, the vapor in the tank is caused to circulate along a closed-loop flow-path defined by the tank and the conduit (8), thereby reducing to a minimum the effect of thermal stratification of the vapor in the tank and, as a result, favoring a homogeneous drying effect of the washload items.

Abstract: A dishwashing machine having a reservoir (6) communicating with the washing tank (1) through a lower aperture (7) connected to the delivery side of a drain pump (3). The reservoir (6) comprises an upper aperture (9) capable of communicating with the outside ambient through a valve (10) which is controlled by the program sequence control switch (13) of the machine so as to open during a pre-determined water discharge phase to enable the reservoir (6) to be filled by the water being let out from the tank (1); to temporarily close so as to prevent said reservoir (6) from emptying after said water discharge phase; and to finally open again so as to enable the water stored in the reservoir (6) to flow back into the washing tank (1), through the lower aperture (7) and the pump (3), to be used during said subsequent phase of the washing process.

Abstract: A method for controlling the amount of water filled in a dishwashing machine through a normally closed valve (18) to carry out a duty cycle of the machine in which the water is sprayed onto the washload items by a circulation pump (10) driven by an electric motor (11). The water is put under pressure by the pump in an intermittent manner with an alternate sequence of pre-set operating periods (T) and pauses (S) during which the motor rotating speed is at its highest value (V.sub.1) and lowest value (V.sub.0), respectively. The valve (18) is opened in at least one subsequent pause (S) following a preceding period (T) in which the pressure of the water in correspondence of the pump (10) decreases below a pre-determined threshold value (P.sub.2).

Abstract: Dishwashing machine including a valve (7) that is open during a water inlet phase and a circulation pump (11) that is energized during the water inlet phase. A control arrangement is driven by a signal (V) that is proportional to the outlet pressure of the circulation pump so as to close the inlet valve (7) when signal variations decrease below a pre-determined value. The circulation pump (11) is driven by a single-phase asynchronous motor (14) with a phase-shift capacitor (15) from which the signal (V) is derived. A further signal (U) can be derived from the capacitor (15) to drive the control arrangement so as to determine the correct de-energization of a discharge pump (18).