Washing machine

Abstract

A washing machine includes a cabinet, an outer tank, an inner tank, a circulation tube, and a circulation pump. The outer tank is held in the cabinet. The inner tank is rotatably mounted in the outer tank so as to accommodate and stir laundry. The circulation tube draws washing water kept in the outer tank and returns it to the outer tank. The circulation pump is located at some midpoint in the circulation tube so as to circulate the washing water. The washing machine further includes, at some midpoint in the circulation tube, a washing water-condition detector for detecting the condition of the washing water. This structure ensures the amount of washing water circulating through the washing water-condition detector, without depending on the operation of the inner tank. Thus, the washing machine can detect the degree of contamination of washing water with high accuracy while maintaining its washing efficiency.

1 . A washing machine comprising;
 a cabinet;   an outer tank held in the cabinet;   an inner tank rotatably mounted in the outer tank, the inner tank accommodating laundry;   an agitating portion for agitating the laundry;   a circulation tube for drawing washing water kept in the outer tank and returning the washing water to the inside of the outer tank;   a circulation pump located at some midpoint in the circulation tube, the circulation pump circulating the washing water; and   a controller for controlling operations of the agitating portion and the circulation pump, wherein   the washing machine further includes, at some midpoint in the circulation tube, a washing water-condition detector for detecting a condition of the washing water.   
     
     
         2 . The washing machine of  claim 1 , wherein
 the controller operates the circulation pump intermittently during a washing step; and   the washing water-condition detector detects a condition of the washing water when the circulation pump is stopped.   
     
     
         3 . The washing machine of  claim 1 , wherein
 the circulation tube allows the washing water to be injected into the inner tank.   
     
     
         4 . The washing machine of  claim 1 , wherein
 the controller synchronizes operations of the agitating portion and the circulation pump.   
     
     
         5 . The washing machine of  claim 1 , wherein
 the controller stops the operation of the agitating portion when a predetermined time has passed after having stopped the circulation pump.   
     
     
         6 . The washing machine of  claim 1 , wherein the controller drives the circulation pump during a rinsing step. 
     
     
         7 . The washing machine of  claim 1 , wherein
 the agitating portion is the inner tank, and the laundry is stirred by rotation of the inner tank.   
     
     
         8 . The washing machine of  claim 1 , further comprising:
 an agitator rotatably mounted on an inner bottom of the inner tank, wherein   the agitating portion is the agitator, and   the laundry is stirred by rotation of the agitator.