Patent ID: 7530132

Claim:
A method for controlling a drum-type washing machine during a dewatering process in which a motor, coupled to a drum, rotates the drum to extract water from laundry contained in the drum, the method comprising: detecting, before the dewatering process, an amount of laundry in the drum; rotating the motor at a first rotating speed; performing at least one eccentricity detection at the first rotating speed being proportional to the detected amount of laundry, to obtain an eccentricity value; accelerating, if the obtained eccentricity value is within a nominal range, the motor from the first rotating speed to a second rotating speed, the second rotating speed being lower than a resonance range of the motor and rotated drum; and entering a main dewatering phase based on said at least one eccentricity detection and wherein the main dewatering phase of the dewatering process is performed at a main dewatering speed determined based on the detected amount of laundry, and wherein the main dewatering speed is set according to a comparison of two successive eccentricity values obtained by said at least one eccentricity detection, and wherein the main dewatering phase is entered after obtaining a final eccentricity value by said at least one eccentricity detection; wherein the second rotating speed of the motor is maintained at a constant level for a first predetermined time before the main dewatering phase is entered; wherein the two successive eccentricity values consist of a current unbalance (UB) value and a previous UB value; and wherein, if the final eccentricity value permits entry to the main dewatering phase, the main dewater speed is set according to the final UB value obtained immediately preceding entry to the main dewatering phase when the current UB value is less than the previous UB value and is set according to the difference between the last two UB values when the current UB value is greater than the previous UB value.