Patent ID: 9080276
Filing Date: 2015-07-14
Classification: D06F

Abstract:
1. A method of operating a washing machine comprising: operating a motor to rotate a tub holding a load at a first rotational rate, the first rotational rate being less than a first predetermined threshold rotational rate and being greater than a rotational rate that enables the load to remain in contact with an inner surface of the rotating tub; identifying a torque applied by the motor to continue to rotate the tub at the first rotational rate; identifying a mass of the load with reference to the torque and the first rotational rate; operating the motor to rotate the tub at a second rotational rate, the second rotational rate being greater than the first predetermined threshold rotational rate; identifying an electrical power level applied to the motor to continue rotation of the tub at the second rotational rate; obtaining an out of balance mass value from a memory with reference to the identified electrical power level applied to the motor, the second rotational rate, and the identified mass; identifying a maximum rotational rate for the tub with reference to the out of balance mass value; and operating the motor to rotate the tub at a third rotational rate that is less than or equal to the identified maximum rotational rate and the third rotational rate being greater than the first predetermined threshold rotational rate.