Patent ID: 7934280

Claim:
A drum-type washing machine, comprising: a tub mounted in a cabinet such that wash water is supplied into the tub; a drum rotatably mounted in the tub such that laundry is put into the drum; a motor that rotates the drum; and a controller that controls a driving of the motor such that, when the drum is rotated, the wash water supplied into the tub reaches an upper part of an inner circumferential surface of the tub so as to clean the inner circumferential surface of the tub, wherein the controller controls a rotation speed of the drum such that the wash water supplied into the tub circulates along the inner circumferential surface of the tub, and wherein the controller controls the rotation speed of the drum to be higher than a predetermined rotation speed of the drum for a washing or rinsing operation and lower than a predetermined rotation speed of the drum for a spin-drying operation.