Patent ID: 7963292

Claim:
A dish washing machine, comprising: a washing tub; at least one injection nozzle disposed in the washing tub; a sump disposed in the washing tub to forward wash water to the at least one injection nozzle and including a filth chamber disposed in the sump; a guide pipe connected between the sump and the at least one injection nozzle; and a bypass pipe, diverging from a portion of the guide pipe, connected to the sump to bypass the wash water in the sump to the guide pipe when pressure of the wash water in the filth chamber exceeds a predetermined pressure level, wherein the sump includes a sump housing forming a lower part of the sump, an impeller casing disposed on the sump housing to receive a washing impeller to pump wash water, the impeller casing being provided with a main channel and a sub channel to guide the flow of the wash water pumped by the washing impeller, a filth chamber communicating with the main channel to collect filth contained in the wash water, and a sampling channel to allow the filth chamber and the main channel to communicate with each other therethrough, and an impeller casing cover to cover the impeller casing, and wherein an end of the bypass pipe is coupled to the impeller casing cover while the end of the bypass pipe is located at an upper part of an outlet of the sampling channel.