Patent ID: 11905637
Assignee: LG ELECTRONICS INC.
Field: Other consumer goods (Other fields)
Classification: CPC D  H  Y | IPC D  H

Claim 0:
1. A laundry treatment machine comprising:
a washing tub;
a washing tub motor to rotate the washing tub;
a drain pump;
a drain motor to operate the drain pump;
a converter to output a direct current (DC) voltage;
an inverter to convert the DC voltage from the converter into an alternating current (AC) voltage based on a switching operation and to output the converted AC voltage to the drain motor;
an output current detector to detect an output current flowing in the drain motor; and
a controller to control the drain motor to rotate at a second speed lower than a first speed and then increase the speed of the drain motor after a predetermined time, when the output current flowing in the drain motor decreases in a state where a speed of the drain motor is the first speed while a water level in the washing tub is kept constant,
wherein the controller controls to supply the same power to the drain motor, when the drain motor is driven at the first speed and when the drain motor is driven at the second speed,
wherein, while the water level in the washing tub decreases, the controller controls the speed of the drain motor to be gradually increased from a third speed lower than the first speed and higher than the second speed,
wherein the output current is substantially constant in a period during which the speed of the drain motor gradually increases from the third speed.