Method for controlling dewatering operation of washing machine

Abstract

A method for controlling dewatering of a washing machine includes detecting an initial reference eccentric position of a drum and an initial amount of eccentricity while a drum of a washing machine is rotated at a low speed, detecting a current eccentric position and a current amount of eccentricity of a drum while the drum is rotated at a low speed again after being rotated at a high speed, and controlling dewatering operation based on the detected initial reference eccentric position, the initial amount of eccentricity, the current eccentric position and the current amount of eccentricity.

1 . A method for controlling dewatering operation of a washing machine, comprising: 
 detecting an initial amount of eccentricity of a drum and an initial reference eccentric position in the drum while the drum is rotated at a low speed;    detecting a current amount of eccentricity of the drum and a current eccentric position in the drum while the drum is rotated at a low speed again after being rotated at a high speed; and    controlling dewatering operation based on the detected initial amount of eccentricity, the initial reference eccentric position, the current amount of the eccentricity and the current eccentric position.    
   
   
       2 . The method of  claim 1 , wherein the initial amount of eccentricity of the drum is detected while the drum of the washing machine is rotated at a low speed; and 
 a drum eccentric position is determined as the initial reference eccentric position at a maximum speed of a range of the low speed at which the drum is operated.    
   
   
       3 . The method of  claim 1 , wherein the current amount of eccentricity is detected while the drum is rotated at the low speed after being rotated at the high speed for a preset time; and 
 a drum eccentric position is determined as the current eccentric position at a maximum speed of a range of the low speed that comes after a rotation at the high speed for the preset time.    
   
   
       4 . The method of  claim 1 , further comprising: 
 detecting a difference of eccentricity value between the current amount of eccentricity and the initial amount of eccentricity;    determining whether the detected difference of eccentricity value is larger than a first preset reference value;    performing dewatering when the detected difference value of eccentricity is not larger than the first preset reference value;    detecting a difference value of position between the current eccentric position and the initial reference eccentric position when the detected difference value of eccentricity is larger than the first preset reference value;    determining whether the difference value of position between the current eccentric position and the initial reference eccentric position is larger than a second preset reference value;    performing dewatering when the difference value of position between the current eccentric position and the initial reference eccentric position is not larger than the second preset reference value; and    returning to detecting the initial amount of eccentricity of the drum after the drum is stopped when the difference value of position between the current eccentric position and the initial reference eccentric position is larger than the second preset reference value.    
   
   
       5 . A method for controlling dewatering operation of a washing machine, comprising: 
 detecting an initial amount of eccentricity of a drum while the drum of a washing machine is rotated at a low speed;    determining a drum eccentric position as an initial reference eccentric position at a maximum speed of a range of the low speed;    detecting a current amount of eccentricity while the drum is rotated at a low speed after being rotated at a high speed for a preset time, and determining a drum eccentric position as a current eccentric position at a maximum speed of the drum; and    controlling dewatering operation of a washing machine based on the initial amount of eccentricity, the initial reference eccentric position, the current amount of eccentricity and the current eccentric position.    
   
   
       6 . The method of  claim 5 , further comprising: 
 detecting a difference value of eccentricity between the current amount of eccentricity and the initial amount of eccentricity;    determining whether the detected difference value of eccentricity is larger than a first preset reference value;    performing a dewatering when the detected difference value is not larger than the first preset reference value;    detecting a difference value of position between the current eccentric position and the initial reference eccentric position;    determining whether the detected difference value of position is larger than a second preset reference value;    performing dewatering when the detected difference value of position is not larger than the second preset reference value; and    returning to detecting the initial amount of eccentricity of the drum after the drum is stopped when the detected phase difference is larger than the second preset reference value.    
   
   
       7 . The method of  claim 6 , wherein returning to detecting the initial amount of eccentricity of the drum after the drum is stopped comprises; 
 performing a series of operations of stopping and then driving the drum a preset number of times, and then returning to detecting the initial amount of eccentricity of the drum when the detected phase difference is larger than the second preset reference value.