Patent ID: 7942023

Claim:
A drum type washing machine comprising a drum rotatably supported around a horizontal or inclined rotary shaft, a motor to rotate the drum, and a control mechanism to control the motor, wherein the control mechanism comprises: a torque control unit to perform torque addition processes of adding pulse type torque during only a period for which the drum makes one rotation in a uniform torque control state in which torque of the motor is uniformly controlled k times (k is an integer not less than 2) and, at the same time, to set a rotation angle of the drum at points of time when the respective torque addition processes are carried out to be one obtained by equally dividing 360 degrees into k pieces; and a weight calculation unit to calculate an average value of rotational accelerations of the motor at the respective torque addition processes and, at the same time, to calculate a weight of laundry received in the drum based on the average value.