Device and method for collecting wastewater in dishwashers

1. An arrangement for forwarding waste water out of a lower region of a dishwashing machine, the arrangement comprising:

a discharge path along which a to-be-discharged fluid is discharged from a lower region of a dishwashing machine, the discharge path extending from a pass on location in the lower region of the respective dishwashing machine to a discharge location at which the to-be-discharged fluid is discharged from the dishwashing machine;

a recirculation start path along which a circulable fluid is forwarded from the lower region of the respective dishwashing machine, the recirculation start path extending from a take over location in the lower region of the respective dishwashing machine to an exit location beyond which the circulable fluid flows further to a washing volume of the dishwashing machine; and

an upstream segment along which flows all fluid that has reached the lower region of the respective dishwashing machine, the upstream segment being communicated with the pass on location associated with the discharge path and the take over location associated with the recirculation start path such that all to-be-discharged fluid flows, on the one hand, through the upstream segment to the pass on location associated with the discharge path and thereafter flows along the discharge path to the discharge location or, on the other hand, all circulable fluid flows through the upstream segment to the take over location associated with the recirculation start path and thereafter flows along the recirculation path to the exit location of the recirculation start path, the upstream segment being formed of:

a pump well,

a sump section,

an inflow section comprising one and only one outlet whereby all to-be-discharged fluid or all circulable fluid flows wherein the inflow section of the pump well extends into and inside of the sump section and wherein the top of the sump section is above the valve means and is open to the external environment to form a vent, and

a valve means for selectively opening the inflow section for the flow of fluid from the pump well into the sump section and closing the inflow section to prevent the flow of fluid from the pump well into the sump section, the upstream segment being operable to advance all to-be-discharged fluid successively through the pump well, the inflow section, and the sump section, whereupon all to-be-discharged fluid is thereafter flowed into the discharge path for ultimate discharge at the discharge location and to advance all circulable fluid successively through the pump well, the inflow section, and the sump section, whereupon all circulable fluid is thereafter flowed into the recirculation path for ultimate forwarding beyond the exit location.

2. The arrangement according to claim 1 and further comprising a controller for controlling the valve means (a) to open during one portion of a respective washing cycle of the dishwashing machine for transfer of waste water through the discharge path via which the waste water is discharged from the dishwasher, (b) to thereafter close the valve means, whereupon fluid thereafter arriving in the lower region of the dishwasher is collected in the pump well, and (c) to thereafter open the valve means during a later portion of the respective washing cycle of the dishwashing machine for flow of fluid along the recirculation path via which the fluid is recirculated to a washing volume of the dishwasher.

3. The arrangement according to claim 1 and further comprising at least one of a lye pump and a circulating pump that is communicated with the sump section.