US 11,952,698 B2
Laundry treatment machine
Junsung Kim, Seoul (KR); Sungwan Kim, Seoul (KR); and Chungill Lee, Seoul (KR)
Assigned to LG ELECTRONICS INC., Seoul (KR)
Appl. No. 17/258,289
Filed by LG ELECTRONICS INC., Seoul (KR)
PCT Filed Jul. 5, 2019, PCT No. PCT/KR2019/008283
§ 371(c)(1), (2) Date Jan. 6, 2021,
PCT Pub. No. WO2020/009526, PCT Pub. Date Jan. 9, 2020.
Claims priority of application No. 10-2018-0079059 (KR), filed on Jul. 6, 2018.
Prior Publication US 2021/0277563 A1, Sep. 9, 2021
Int. Cl. D06F 33/42 (2020.01); D06F 34/10 (2020.01); D06F 34/14 (2020.01); D06F 39/08 (2006.01); D06F 103/18 (2020.01); D06F 103/24 (2020.01); D06F 105/08 (2020.01)
CPC D06F 33/42 (2020.02) [D06F 34/14 (2020.02); D06F 34/10 (2020.02); D06F 39/085 (2013.01); D06F 2103/18 (2020.02); D06F 2103/24 (2020.02); D06F 2105/08 (2020.02)] 15 Claims
OG exemplary drawing
 
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; and
a controller configured to control the drain motor to operate at a first speed, a second speed less than the first speed, and a stop by changing a speed of the drain motor when the washing tub motor is accelerated,
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 the controller controls the drain motor to rotate at the first speed, the second speed, and a third speed less than the first speed by changing the speed of the drain motor, before the washing tub motor is accelerated,
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.