Patent ID: 7640940

Claim:
A drive unit for dish washing machines, comprising: a sump for receiving wash water; a pump housing positioned inside the sump such that the pump housing is supported by the sump, the pump housing having a washing impeller located therein; a flow channel housing positioned to cover the top of the pump housing, the flow channel housing having flow channels for guiding some of the wash water pumped out from the washing impeller to washing arms and having a solid waste chamber for filtering some of the pumped-out wash water; a filter housing thermally fused to the upper part of the flow channel housing to define an integral housing, the filter housing having a filter opening, which corresponds to the solid waste chamber and having an upper chamber for filtering some of the pumped-out wash water disposed such that the upper chamber deviates from the solid waste chamber; and an arm holder thermally fused to the upper part of the filter housing to define an integral structure, the arm holder having a filter positioned to cover the filter opening of the filter housing, wherein the upper chamber has a bottom surface that is higher, by a predetermined amount, than a bottom surface of the solid waste chamber such that the bottom surfaces of the upper chamber and the solid waste chamber are configured to define a stepped structure, the upper chamber communicating with the solid waste chamber, and the filter of the arm holder is positioned to cover the solid waste chamber and the upper chamber.