Dishwasher fill system

Claim 1

A positive water fill, flood prevention and cycle advance system for a dishwasher having a sump with an overflow level, fill valve means adapted for supplying a water level to the sump from a domestic supply of water available at pressures normally between about 30 pounds per square inch and 60 pounds per square inch but occasionally at below normal pressures to about 4 pounds per square inch and at above normal pressures to about 120 pounds per square inch, a pump motor for recirculating the water supplied and a timer for controlling said fill valve means and said pump motor in a dishwashing cycle including consecutive cycle portions of fill and recirculation, said timer including means for continuous energization thereof throughout said cycle portions, said system including a first timer switch in series with said fill valve means and controlled by said timer for a predetermined period to effect a water level in said sump above normal but below overflow when said water valve means is adapted for supplying water from a domestic supply of water aT normal and above normal pressures, a pressure switch having a first position in series with said first timer switch for enabling the supply of water to the sump and movable to a second position in series with said pump motor when the water level in said sump reaches normal to terminate the supply of water to said sump irrespective of the timer control of said first timer switch thereby to prevent floods and to energize said pump motor for changing said fill cycle portion to said recirculation cycle portion during said predetermined period, a second timer switch in series with said pump motor and said pressure switch in its second position and controlled by said timer before said pressure switch is movable to its second position and before the end of said predetermined period to enable the energization of said pump motor for said recirculation cycle portion as soon as the pressure switch moves to its second position whereby said recirculation cycle portion may be extended by the amount of time before the end of said predetermined period that said supply of water to said sump is terminated, and a third timer switch in series with said pump motor and said second timer switch and in shunt with said pressure switch, said third timer switch controlled by said timer to bypass said pressure switch and energize said pump motor through said second timer switch thereby to advance the dishwashing cycle irrespective of the position of said pressure switch or a below normal water level in said sump when said water valve means is adapted for supplying water from a domestic supply of water at below normal pressures.