Dishwasher filter system

A filter system for a dishwasher having a floor, a wash pump and a drain pump comprising:

• a sump in the floor having a sidewall and a bottom wall having an inlet leading to the wash pump and an inlet leading to the drain pump;
• a filter assembly positioned in the sump including:
• a generally vertical filter retainer and an overlying perforate hood positioned adjacent the filter retainer;
• a multiple porosity filter element carried on at least a portion of an outer surface of the filter retainer;
• and
• a back wash sprayer connected to the wash pump and rotatably mounted inside the filter retainer and having at least one nozzle directed toward the filter element, wherein the inlet leading to the wash pump is positioned inside the filter assembly and the inlet leading to the drain pump is positioned outside the filter assembly;
• a dishwasher control, and a sensor positioned on the sidewall of the sump to detect accumulation of soil particles on the filter element and connected to the dishwasher control and arranged to activate the drain pump to remove soil particles from the sump when a predetermined accumulation of soil particles is detected;
• and
• a spray arm rotatably mounted above the filter system, wherein the sensor is arranged to detect that the spray arm is rotating and the dishwasher control is arranged to provide a check spray arm signal to the user when the sensor fails to detect spray arm rotation.

A dishwasher having a floor and a plurality of walls, a wash pump and a drain pump comprising:

• a sump in the floor having a sidewall, a bottom wall with an inlet leading to the wash pump and an inlet leading to the drain pump and a sump conduit extending upwardly from the bottom wall and connected to the outlet of the wash pump;
• a filter assembly positioned in the sump over the sump conduit and including:
• a generally vertical filter retainer and an overlying perforate hood;
• a multiple porosity filter element carried on the filter retainer;
• and
• a back wash sprayer rotatably mounted on the sump conduit inside the filter element and having two nozzles directed toward the filter element and vertically spaced on opposite sides of a generally cylindrical hub rotatably carried on the sump conduit, and wherein the sump conduit has one or more openings aligned with the hub to provide a supply of wash water to the back wash sprayer nozzles;
• and
• a spray arm rotatably mounted on the sump conduit above the filter assembly, wherein the inlet to the wash pump is positioned inside the filter assembly and the inlet to the drain pump is positioned outside the filter assembly.

A dishwasher having a floor and a plurality of side walls, a wash pump and a drain pump, the floor and plurality of sidewalls define a drawer having a mounting cavity for the wash pump at one corner and a mounting cavity for the drain pump at another corner, the dishwasher comprising:

• a sump in the floor having a sidewall, a bottom wall with an inlet leading to the wash pump and an inlet leading to the drain pump and a sump conduit extending upwardly from the bottom wall and connected to the outlet of the wash pump;
• a wash pump inlet conduit connecting the wash pump inlet to the wash pump;
• a wash pump outlet conduit connecting the wash pump to the sump conduit;
• a drain pump inlet conduit connecting the drain pump inlet to the drain pump;
• a filter assembly positioned in the sump over the sump conduit and including:
• a generally vertical filter retainer and an overlying perforate hood;
• a multiple porosity filter element carried on the filter retainer;
• and
• a back wash sprayer rotatably mounted on the sump conduit inside the filter element and having at least one backwash nozzle directed toward the filter element;
• and
• a spray arm rotatably mounted on the sump conduit above the filter assembly;
• wherein the inlet to the wash pump is positioned inside the filter assembly and the inlet to the drain pump is positioned outside the filter assembly.

A dishwasher having a floor and a plurality of walls, a wash pump and a drain pump comprising:

• a sump in the floor having a sidewall, a bottom wall with an inlet leading to the wash pump and an inlet leading to the drain pump and a sump conduit extending upwardly from the bottom wall and connected to the outlet of the wash pump;
• a filter assembly positioned in the sump over the sump conduit and including:
• a generally vertical filter retainer and an overlying perforate hood;
• a multiple porosity filter element carried on the filter retainer;
• and
• a back wash sprayer rotatably mounted on the sump conduit inside the filter element and having at least one backwash nozzle directed toward the filter element;
• and
• a spray arm rotatably mounted on the sump conduit above the filter assembly, the spray arm comprising a top member, a bottom member, and a plurality of nozzles configured to spray wash water in multiple directions, wherein the nozzles are positioned along the inside edge of the top member and the bottom member includes a plurality of diverter channels positioned along the inside edge of the bottom member beneath the plurality of nozzles to divert wash water to the nozzles;
• wherein the inlet to the wash pump is positioned inside the filter assembly and the inlet to the drain pump is positioned outside the filter assembly.

A dishwasher having a floor and a plurality of walls, a wash pump and a drain pump comprising:

• a sump in the floor having a sidewall, a bottom wall with an inlet leading to the wash pump and an inlet leading to the drain pump and a sump conduit extending upwardly from the bottom wall and connected to the outlet of the wash pump;
• a filter assembly positioned in the sump over the sump conduit and including:
• a generally vertical filter retainer and an overlying perforate hood;
• a multiple porosity filter element carried on the filter retainer;
• and
• a back wash sprayer rotatably mounted on the sump conduit inside the filter element and having at least one backwash nozzle directed toward the filter element;
• a spray arm rotatably mounted on the sump conduit above the filter assembly, wherein the inlet to the wash pump is positioned inside the filter assembly and the inlet to the drain pump is positioned outside the filter assembly;
• and
• a dishwasher control, and a pressure sensor positioned on the sidewall of the sump to detect accumulation of soil particles on the filter element and connected to the dishwasher control and arranged to activate the drain pump to remove soil particles from the sump when a predetermined accumulation of soil particles is detected, the sensor being arranged to detect that the back wash sprayer is rotating and the dishwasher control is arranged to provide a check filter signal to the user when the sensor fails to detect back wash sprayer rotation.