Dishwasher

Abstract

A dishwasher uses washing water containing microbubbles. The dishwasher includes a flow path forming rib that defines a washing water flow path inside an upper body and a lower body of a spray arm. The dishwasher further includes a fusion rib for fusion coupling the upper body and the lower body to effectively secure a flow path structure and simplify a fastening structure.

What is claimed is: 
     
         1 . A dishwasher comprising:
 a tub that defines a washing space;   a sump disposed at a lower side of the tub and configured to store washing water; and   a spray arm configured to discharge the washing water from the sump into the washing space,   wherein the spray arm comprises a main body portion that defines (i) an opening configured to receive the washing water from the sump, (ii) a first flow path configured to carry the washing water, and (iii) a suction hole in fluid communication with the washing space, the spray arm being configured to discharge the washing water having passed through the first flow path into the washing space,   wherein the first flow path comprises:
 a connection flow path configured to guide the washing water introduced through the opening of the main body portion, 
 a buffer flow path connected to the connection flow path, 
 an air suction flow path connected to the buffer flow path and configured to guide air introduced from the washing space through the suction hole, and 
 a discharge flow path connected to the air suction flow path, the discharge flow path having a discharge hole configured to discharge the washing water having passed through the air suction flow path toward the washing space, and 
   wherein a cross-sectional area of the buffer flow path is larger than a cross-sectional area of the air suction flow path.   
     
     
         2 . The dishwasher of  claim 1 , wherein the first flow path further comprises an air flow passage configured to supply the air introduced through the suction hole to the air suction flow path. 
     
     
         3 . The dishwasher of  claim 2 , wherein the air flow passage comprising at least one bending portion configured to change a flow direction of the air in the air flow passage. 
     
     
         4 . The dishwasher of  claim 2 , wherein the air flow passage is connected to the air suction flow path at a position that is closer to the discharge flow path than to the buffer flow path. 
     
     
         5 . The dishwasher of  claim 2 , wherein the cross-sectional area of the air suction flow path is larger than a cross-sectional area of the air flow passage. 
     
     
         6 . The dishwasher of  claim 1 , wherein the suction hole is defined at a lower surface of the spray arm. 
     
     
         7 . The dishwasher of  claim 1 , wherein the buffer flow path comprises:
 an expansion portion that is disposed adjacent to the connection flow path and expands the cross-sectional area of the buffer flow path along a flow direction of the washing water in the buffer flow path;   a retaining portion that is disposed downstream of the expansion portion and maintains the cross-sectional area of the buffer flow path along the flow direction of the washing water; and   a contraction portion that is disposed downstream of the retaining portion and contracts the cross-sectional area of the buffer flow path along the flow direction of the washing water.   
     
     
         8 . The dishwasher of  claim 1 , wherein the buffer flow path comprises:
 an inlet configured to receive the washing water from the connection flow path; and   an outlet configured to discharge the washing water in the buffer flow path to the air suction flow path.   
     
     
         9 . The dishwasher of  claim 8 , wherein a center of the inlet is offset from a line that passes through a center of the outlet. 
     
     
         10 . The dishwasher of  claim 1 , wherein the cross-sectional area of the air suction flow path is larger than a cross-sectional area of the connection flow path.