Drain pump and washing machine having the same

Abstract

A drain pump capable of easily discharging air in the drain pump, and a washing machine having the same. The drain pump includes a washing water inlet compartment, a drain pump compartment configured to pump washing water contained in the washing water inlet compartment to an outside, a suction port provided between the washing water inlet compartment and the drain pump compartment to move the washing water from the washing water inlet compartment to the drain pump compartment, a drain line to connect the drain pump compartment to an outside to discharge the washing water, and an air outlet port provided on the drain pump compartment to discharge air contained in the drain pump compartment to an outside, wherein the air outlet port is connected to the drain line.

What is claimed is: 
     
         1 . A drain pump comprising:
 a washing water inlet compartment;   a drain pump compartment configured to pump washing water contained in the washing water inlet compartment to an outside;   a suction port provided between the washing water inlet compartment and the drain pump compartment to move the washing water from the washing water inlet compartment to the drain pump compartment;   a drain line to connect the drain pump compartment to the outside, to discharge the washing water; and   an air outlet port provided on the drain pump compartment to discharge air contained in the drain pump compartment,   wherein the air outlet port is connected to the drain line.   
     
     
         2 . The drain pump of  claim 1 , wherein air naturally flows from the air outlet port to the drain line due to the difference in pressure between the drain pump compartment and the drain line. 
     
     
         3 . The drain pump of  claim 1 , wherein the air outlet port protrudes at an upper portion of the drain pump compartment. 
     
     
         4 . The drain pump of  claim 1 , further comprising an air inlet port provided on the drain line, wherein the air outlet port is connected to the air inlet port. 
     
     
         5 . The drain pump of  claim 4 , further comprising an air passage to connect the air outlet port to the air inlet port. 
     
     
         6 . The drain pump of  claim 5 , wherein the air passage comprises a rubber hose. 
     
     
         7 . The drain pump of  claim 4 , wherein the air inlet port is integrally formed with the drain line. 
     
     
         8 . The drain pump of  claim 4 , wherein the air inlet port is separately formed with the drain line and coupled to the drain line. 
     
     
         9 . The drain pump of  claim 1 , wherein the drain line comprises a drain passage connected to the drain pump compartment, and an air passage connected to the air outlet port. 
     
     
         10 . The drain pump of  claim 9 , wherein the air passage is branched from the drain passage. 
     
     
         11 . The drain pump of  claim 9 , wherein the air passage is integrally formed with the drain passage. 
     
     
         12 . The drain pump of  claim 9 , wherein the air passage has a diameter smaller than a diameter of the drain passage. 
     
     
         13 . The drain pump of  claim 1 , wherein the drain line comprises an outlet port protruded at the pump case, and a drain hose including one end connected to the outlet port and the other end extended to an outside. 
     
     
         14 . A drain pump comprising:
 a pump case configured to accommodate washing water;   a pumping motor provided at one end of the pump case to pump the washing water to an outside;   a drain hose connected to the pump case while being adjacent to the pumping motor such that the washing water pumped by the pumping motor flows to an outside;   an air outlet port formed at a side of an upper portion of the pump case to discharge air, the side adjacent to the pumping motor;   an air inlet port protruded at the drain hose; and   an air passage to connect the air outlet port to the air inlet port.   
     
     
         15 . The drain pump of  claim 14 , wherein air naturally flows from the air outlet port to the air inlet port due to the difference in pressure between the drain hose and the pump case, the difference in pressure caused by the difference in velocity between the washing water flowing in the drain hose and the washing water flowing in the pump case. 
     
     
         16 . A drain pump comprising:
 a pump case configured to accommodate washing water;   a pumping motor provided at a portion of the pump case to generate a driving force to allow the washing water to be forcedly discharged to an outside;   a drain hose connected to the portion of the pump case, at which the pumping motor is provided, to guide the washing water to an outside;   an air outlet port protruded at an upper portion of the pump case, at which the pumping motor is provided, to discharge air; and   an air passage including one end connected to the air outlet port and the other end connected to the drain hose.   
     
     
         17 . The drain pump of  claim 16 , wherein the air passage is integrally formed with the drain hose. 
     
     
         18 . A washing machine provided with a tub, a drain pump to pump washing water in the tub, and a drain hose configured to allow the washing water pumped by the drain pump to flow therethrough,
 wherein the drain pump comprises:   a washing water inlet compartment into which the washing water is introduced from the tub;   a drain pump compartment provided with a suction port to draw the washing water in the washing water inlet compartment, and an outlet port connected to a drain hose which is configured to drain the washing water;   an air outlet port protruded at an upper portion of the drain pump compartment; and   an air passage to connect the air outlet port to the drain hose.   
     
     
         19 . The washing machine of  claim 18 , wherein the drain hose comprises an air inlet port protruded at the drain hose,
 wherein the air passage includes one end connected to the air outlet port and the other end connected to the air inlet port.   
     
     
         20 . The washing machine of  claim 18 , wherein the other end of the air passage is integrally formed with the drain hose. 
     
     
         21 . A washing machine comprising:
 a cabinet;   a tub disposed at an inside the cabinet to accommodate washing water;   a drain pump disposed at a lower portion of the tub to drain the washing water contained in the tub;   a drain line connected to the drain pump to guide the washing water, which is pumped by the drain pump, to an outside the cabinet; and   an air passage to connect the drain pump to the drain line to discharge air contained in the drain pump.   
     
     
         22 . The washing machine of  claim 21 , wherein the drain pump comprises an air outlet port protruded upward, at the drain pump, and the drain line comprises an air inlet port protruded upward, at the drain line,
 wherein one end of the air passage is connected to the air outlet port and the other end of the air passage is connected to the air inlet port.   
     
     
         23 . The washing machine of  claim 21 , wherein the drain pump comprises an air outlet port protruded upward, at the drain pump,
 wherein one end of the air passage is connected to the air outlet port and the other end of the air passage is integrally formed with the drain line.