公开(公告)号：US20210222340A1

公开(公告)日：2021-07-22

申请号：US17258058

申请日：2019-07-05

Applicant: LG ELECTRONICS INC.

Inventor： Wonseok PARK ,  Jieon KIM ,  Kiwook LEE

IPC: D06F34/10 ,  D06F33/42 ,  D06F37/30 ,  D06F39/08

Abstract: The present disclosure relates to a laundry treatment machine. A laundry treatment machine comprises: an inverter to convert the DC voltage from the converter into alternating current (AC) voltage by a switching operation and to output the converted AC voltage to a motor; and a controller that controls such that, while a washing tub motor is rotating at a constant speed, a drain motor operates in a first period during which the speed of the drain motor increases, a second period during which the speed of the drain motor decreases after the first period, and a third period during which the speed of the drain motor decreases after the second period, wherein a rising slope in the second period is less than a falling slope in the third period. Accordingly, a speed ripple of the drain motor may be reduced.

公开(公告)号：US20210285141A1

公开(公告)日：2021-09-16

申请号：US17258219

申请日：2019-07-05

Applicant: LG ELECTRONICS INC.

Inventor： Wonseok PARK ,  Junsung KIM ,  Kiwook LEE

IPC: D06F33/42 ,  D06F39/08 ,  D06F37/30 ,  D06F23/04 ,  F04D15/00 ,  F04D13/06 ,  H02P23/14

Abstract: The present disclosure relates to a laundry treatment machine. A pump motor provided in a drain pump is controlled to correspond to the operation of the main motor and the water level, so that the pump motor slows down based on the speed of rotation of the main motor and the water level and keeps operating at low speed. Therefore, the pump motor is able to keep operating without stopping operation, and the amount of noise caused by the start-up of the motor is reduced, and the time taken to align the rotor of the motor in position is reduced, thereby reducing drainage time and improving the drainage performance of the drain pump.