Dishwasher

Abstract

The present invention relates to a dishwasher. The dishwasher of the present invention may include a sump for holding cleaning water, a cleaning pump for pumping the cleaning water from the sump, a spray arm for spraying the cleaning water through two or more nozzles, a supply flow passage for forming a flow passage to supply the cleaning water pumped by the cleaning pump to the spray arm, and an air mixing unit for drawing external air to spray the cleaning water through the nozzles together with the air. The air mixing unit may be mounted between the nozzle which sprays the cleaning water and an inlet of the supply flow passage connected to the spray arm, or the end of the supply flow passage connected to the spray arm. Accordingly, the washability of the dishwasher can be improved without increasing the amount of water used.

What is claimed is: 
     
         1 . A dishwasher comprising:
 a sump for holding cleaning water;   a cleaning pump for pumping the cleaning water from the sump;   a spray arm for spraying the cleaning water through two or more nozzles;   a supply flow passage for forming a flow passage to supply the cleaning water pumped by the cleaning pump to the spray arm; and   an air mixing unit for drawing external air to spray the cleaning water through the nozzles together with the air.   
     
     
         2 . The dishwasher as claimed in  claim 1 , wherein the air mixing unit is mounted between the nozzle which sprays the cleaning water and a connection portion which connects the spray arm to the supply flow passage to introduce the cleaning water to the spray arm. 
     
     
         3 . The dishwasher as claimed in  claim 2 , wherein the air mixing unit is mounted between the nozzle closest to the connection portion and the connection portion. 
     
     
         4 . The dishwasher as claimed in  claim 2 , wherein the air mixing unit includes an air introduction hole formed in a direction different from a direction in which the nozzle sprays the cleaning water. 
     
     
         5 . The dishwasher as claimed in  claim 4 , wherein the air mixing unit includes the air introduction hole formed toward a rotation direction of the spray arm. 
     
     
         6 . The dishwasher as claimed in  claim 4 , wherein the air mixing unit includes the air introduction hole formed in an upper side or an underside thereof perpendicular to the rotation direction of the spray arm. 
     
     
         7 . The dishwasher as claimed in  claim 4 , wherein a number and a size of the air introduction hole are determined based on a cross sectional area of the nozzles. 
     
     
         8 . The dishwasher as claimed in  claim 1 , wherein the air mixing unit is mounted to an end of the supply flow passage connected to the spray arm. 
     
     
         9 . The dishwasher as claimed in  claim 8 , wherein the air mixing unit is mounted to a portion closest to the connection portion of the spray arm among portions of the supply flow passage through which the cleaning water flows in a vertical direction. 
     
     
         10 . The dishwasher as claimed in  claim 8 , wherein the air mixing unit is mounted to a portion closest to the connection portion of the spray arm among portions of the supply flow passage through which the cleaning water flows in a horizontal direction. 
     
     
         11 . The dishwasher as claimed in  claim 1 , wherein the air mixing unit includes;
 an air introduction hole for introduction of the air from an outside of the tube,   a compression tube having a cross sectional area reduced in a flow direction of the cleaning water,   an air suction hole for serving as a suction passage of the air introduced through the air introduction hole thus into an inside of the tube, and   a buffer portion for buffering a pressure difference between the inside of the tube and the outside of the tube.   
     
     
         12 . The dishwasher as claimed in  claim 11 , wherein the air mixing unit includes two or more suction holes formed in symmetry. 
     
     
         13 . The dishwasher as claimed in  claim 11 , wherein the air suction hole is formed at an end portion of the compression tube with reference to a direction the cleaning water flows. 
     
     
         14 . The dishwasher as claimed in  claim 11 , wherein the buffering portion has a donut shape surrounding the cross sectional area reducing portion of the compression tube. 
     
     
         15 . The dishwasher as claimed in  claim 11 , wherein the air introduction hole and the air suction hole are not arranged on a line in a radial direction with reference to an axis of the tube.