Method for controlling dehydration of washing machine

Abstract

A method for controlling dehydration of a washing machine, in which one reference degree of eccentricity in the direction, in which the vibration of a tub is large, is set to be lower than the other reference degree of eccentricity in the direction, in which the vibration of the tub is small, or one reference degree of eccentricity in the direction to the installation of a drying device is set to be lower than the other reference degree of eccentricity in the reverse direction, thereby preventing the washing machine from being excessively vibrated and allowing the washing machine to easily perform a dehydrating operation.

1 . A method for controlling dehydration of a washing machine, in which reference degrees of eccentricity in the clockwise and counterclockwise direction of a drum, for determining whether or not main dehydration is performed, are set to different values.  
   
   
       2 . The method as set forth in  claim 1 , 
 wherein the reference degree of eccentricity in the direction, in which the vibration of a tub is large, is set to be lower than the reference degree of eccentricity in the direction, in which the vibration of the tub is small.    
   
   
       3 . The method as set forth in  claim 1 , 
 wherein, in case that a drying device is eccentrically installed at left or right side from the center of a tub, one reference degree of eccentricity in the direction of installation of the drying device is set to be lower than the other reference degree of eccentricity in the reverse direction.    
   
   
       4 . The method as set forth in  claim 1 , 
 wherein, in case that the numbers of dampers connected to left and right sides of a tub differ from each other, one reference degree of eccentricity in the direction to the dampers having a small number is set to be lower than the other reference degree of eccentricity in the reverse direction.    
   
   
       5 . The method as set forth in  claim 1 , 
 wherein, in case that the numbers of springs connected to left and right sides of a tub differ from each other, one reference degree of eccentricity in the direction to the springs having a small number is set to be lower than the other reference degree of eccentricity in the reverse direction.    
   
   
       6 . A method for controlling dehydration of a washing machine, comprising the steps of: 
 (i) rotating a drum in one direction out of the clockwise and counterclockwise directions, and sensing a degree of eccentricity;    (ii) stopping the rotation of the drum when the degree of eccentricity sensed in step (i) is not lower than a first reference degree of eccentricity, and performing main dehydration when the degree of eccentricity sensed in step (i) is lower than the first reference degree of eccentricity;    (iii) rotating the drum in the direction reverse to the rotation in step (i) when the rotation of the drum is stopped in step (ii), and sensing a degree of eccentricity; and    (iv) stopping the rotation of the drum when the degree of eccentricity sensed in step (iii) is not lower than a second reference degree of eccentricity set to a value differing from that of the first reference degree of eccentricity, and performing main dehydration when the degree of eccentricity sensed in step (iii) is lower than the second reference degree of eccentricity,    wherein all steps from step (i) are repeated in case that the rotation of the drum is stopped in step (iv).    
   
   
       7 . The method as set forth in  claim 6 , 
 wherein, in the sense of the degree of eccentricity, a motor for rotating the drum is accelerated such that the rotational frequency (rpm) of the motor reaches a predetermined rotational frequency (rpm), the motor is maintained at a constant rotational speed for a predetermined time when the rotational frequency (rpm) of the motor reaches the predetermined rotational frequency (rpm), and then the motor is turned off; and the degree of eccentricity is sensed using a variation of the rotational speed (rpm) during a time of maintaining the motor at the constant speed.    
   
   
       8 . The method as set forth in  claim 6 , 
 wherein one reference degree of eccentricity, out of the first and second reference degrees of eccentricity, in the direction, in which the vibration of a tub is large, is set to be lower than the other reference degree of eccentricity in the direction, in which the vibration of the tub is small.    
   
   
       9 . The method as set forth in  claim 6 , 
 wherein, in case that a drying device is eccentrically installed at left or right side from the center of a tub, one reference degree of eccentricity, out of the first and second reference degrees of eccentricity, in the direction of installation of the drying device is set to be lower than the other reference degree of eccentricity in the reverse direction.    
   
   
       10 . The method as set forth in  claim 6 , 
 wherein, in case that the numbers of dampers connected to left and right sides of a tub differ from each other, one reference degree of eccentricity, out of the first and second reference degrees of eccentricity, in the direction to the dampers having a small number is set to be lower than the other reference degree of eccentricity in the reverse direction.    
   
   
       11 . The method as set forth in  claim 6 , 
 wherein, in case that the numbers of springs connected to left and right sides of a tub differ from each other, one reference degree of eccentricity, out of the first and second reference degrees of eccentricity, in the direction to the springs having a small number is set to be lower than the other reference degree of eccentricity.    
   
   
       12 . A method for controlling dehydration of a washing machine, comprising the steps of: 
 (i) rotating a drum in one direction out of the clockwise and counterclockwise directions, and sensing a degree of eccentricity;    (ii) stopping the rotation of the drum and performing disentanglement of laundry when the degree of eccentricity sensed in step (i) is not lower than a first reference degree of eccentricity, and performing main dehydration when the degree of eccentricity sensed in step (i) is lower than the first reference degree of eccentricity;    (iii) rotating the drum in the direction reverse to the rotation in step (i) when the rotation of the drum is stopped and the disentanglement of laundry is performed in step (ii), and sensing a degree of eccentricity; and    (iv) stopping the rotation of the drum and performing disentanglement of laundry when the degree of eccentricity sensed in step (iii) is not lower than a second reference degree of eccentricity set to a value differing from that of the first reference degree of eccentricity, and performing main dehydration when the degree of eccentricity sensed in step (iii) is lower than the second reference degree of eccentricity,    wherein all steps from step (i) are repeated in case that the rotation of the drum is stopped and the disentanglement of laundry is performed in step (iv).    
   
   
       13 . The method as set forth in  claim 12 , 
 wherein, in the sense of the degree of eccentricity, a motor for rotating the drum is accelerated such that the rotational frequency (rpm) of the motor reaches a predetermined rotational frequency (rpm), the motor is maintained at a constant rotational speed for a predetermined time when the rotational frequency (rpm) of the motor reaches the predetermined rotational frequency (rpm), and then the motor is turned off; and the degree of eccentricity is sensed using a variation of the rotational speed (rpm) during a time of maintaining the motor at the constant speed.    
   
   
       14 . The method as set forth in  claim 12 , 
 wherein one reference degree of eccentricity, out of the first and second reference degrees of eccentricity, in the direction, in which the vibration of a tub is large, is set to be lower than the other reference degree of eccentricity in the direction, in which the vibration of the tub is small.    
   
   
       15 . The method as set forth in  claim 12 , 
 wherein, in case that a drying device is eccentrically installed at left or right side from the center of a tub, one reference degree of eccentricity, out of the first and second reference degrees of eccentricity, in the direction of installation of the drying device is set to be lower than the other reference degree of eccentricity in the reverse direction.    
   
   
       16 . The method as set forth in  claim 12 , 
 wherein, in case that left and right suspension systems of the tub are bilaterally asymmetric, one reference degree of eccentricity, out of the first and second reference degrees of eccentricity, in the direction to the suspension system having relatively large vibration is set to be lower than the other reference degree of eccentricity in the reverse direction.    
   
   
       17 . The method as set forth in  claim 12 , 
 wherein, in case that the numbers of dampers connected to left and right sides of a tub differ from each other, one reference degree of eccentricity, out of the first and second reference degrees of eccentricity, in the direction to the dampers having a small number is set to be lower than the other reference degree of eccentricity in the reverse direction.    
   
   
       18 . The method as set forth in  claim 12 , 
 wherein, in case that the numbers of springs connected to left and right sides of a tub differ from each other, one reference degree of eccentricity, out of the first and second reference degrees of eccentricity, in the direction to the springs having a small number is set to be lower than the other reference degree of eccentricity in the reverse direction.    
   
   
       19 . The method as set forth in  claim 12 , 
 wherein the rotations of the drum in the clockwise and counterclockwise directions are alternately achieved in the disentanglement of laundry.    
   
   
       20 . The method as set forth in  claim 12 , 
 wherein the rotation of the motor in the counterclockwise direction is performed after a designated time from the stop of the rotation of the drum in the clockwise direction elapses in the disentanglement of laundry.