Method of detecting washing machine unbalance and operation control method using the same

Abstract

A method of detecting a dewatering unbalance of a washing machine and an operation control method using the same is provided, by which a system stability on dewatering is enhanced by controlling a dewatering speed to be appropriate for a state of unbalance that is quickly and accurately detected at an early stage of the dewatering. In a washing machine sequentially performing washing, rinsing, draining, and dewatering on a washing tub holding water and laundry therein, a method of detecting a dewatering unbalance of the washing machine, including a step of detecting an unbalance amount through a variation width of a rotational speed of the washing tub on performing the dewatering.

What is claimed is:  
     
         1 . In a washing machine sequentially performing washing, rinsing, draining, and dewatering on a washing tub holding water and laundry therein, a method of detecting a dewatering unbalance of the washing machine, comprising a step of detecting an unbalance amount through a variation width of a rotational speed of the washing tub on performing the dewatering.  
     
     
         2 . The method as claimed in  claim 1 , wherein the variation width of the rotational speed of the washing tub is detected from a first resonance RPM band.  
     
     
         3 . The method as claimed in  claim 2 , herein the variation width of the rotational speed of the washing tub is detected from a steady rotational speed section.  
     
     
         4 . In a washing machine sequentially performing washing, rinsing, draining, and dewatering on a washing tub holding water and laundry therein, an operation control method of the washing machine, comprising steps of: 
 detecting an unbalance amount through a variation width of a rotational speed of the washing tub on entering the dewatering; and    performing the dewatering at a rotational speed appropriate for the detected unbalance amount.    
     
     
         5 . The method as claimed in  claim 4 , wherein the variation width of the rotational speed of the washing tub is detected from a first resonance RPM band.  
     
     
         6 . The method as claimed in  claim 5 , herein the variation width of the rotational speed of the washing tub is detected from a steady rotational speed section.  
     
     
         7 . The method as claimed in  claim 5 , wherein the rotational speed of the dewatering is determined to belong to one of a normal rotational speed section, an intermediate rotational speed section, and a minimum rotational speed section, according to a range to which the detected unbalance amount belongs.  
     
     
         8 . In detecting an unbalance amount through a variation width of a rotational speed of a washing tub of a washing machine on performing dewatering, the washing machine sequentially performing washing, rinsing, draining, and the dewatering on the washing tub holding water and laundry therein, a method of detecting a dewatering unbalance of the washing machine, comprising steps of: 
 detecting the variation width of the rotational speed of the washing tub from a steady rotational speed section among a first resonance RPM band;    if RPM is reduced by more than a predetermined amount, generating an error-induction possible signal;    if the error-induction possible signal is generated, detecting an RPM value per unit time within a predetermined time range from a moment of the generation of the error signal; and    finding an unbalance determination value using root mean square based on the detected RPM values.