Patent ID: 11952698
Assignee: LG ELECTRONICS INC.
Field: Other consumer goods (Other fields)
Classification: CPC D  Y | IPC D

Claim 10:
11. 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; and
a controller configured to control the drain motor to operate in a first mode operating at a plurality of speeds by changing a speed of the drain motor before the washing tub motor is accelerated, and to operate in a second mode operating at a plurality of speeds by changing the speed of the drain motor when the washing tub motor is accelerated,
wherein a speed in the first mode is greater than a speed in the second mode,
wherein the controller is configured to control the drain pump to gradually decrease the speed of the drain motor without stopping, before the washing tub motor is accelerated,
wherein, after the acceleration of the washing tub motor, the controller controls the drain motor to operate in a third mode in which the drain pump is repeatedly turned on and off,
wherein an amount of wash water flowing into the drain pump before the washing tub motor is accelerated is greater than an amount of wash water flowing into the drain pump when the washing tub motor is accelerated.