Washing machine motor and washing machine comprising same

Patent metadata

Field	Value
Publication number	US-9976243-B2
Application number	US-201415022000-A
Country	US
Kind code	B2
Filing date	Oct 2, 2014
Priority date	Oct 2, 2013
Publication date	May 22, 2018
Grant date	May 22, 2018

Abstract

Provided is a washing machine motor including: an outer rotor connected with an outer shaft; an inner rotor connected with an inner shaft; a stator disposed with an air gap between the inner rotor and the outer rotor and driving the inner rotor and the outer rotor independently; and a planetary gear set provided in the inner shaft to thus decelerate a rotational speed of the inner shaft. The outer shaft is rotated at the same speed as that of the outer rotor, and the inner shaft is decelerated compared to the rotational speed of the inner rotor, so as to increase the torque of the inner shaft. The washing machine motor enables a small-torque output from the inner rotor to drive the pulsator through a planetary gear set and a large-torque output from the outer rotor to drive the wash tub through the planetary gear set.

First claim

The invention claimed is:

1. A washing machine motor driving apparatus comprising:
an outer rotor;
an inner rotor;
a double stator disposed with an air gap between the inner rotor and the outer rotor, and driving the inner rotor and the outer rotor independently;
a first cylindrical outer shaft connected to the outer rotor;
a second cylindrical outer shaft connected to a washing tub;
a first inner shaft rotatably disposed inside the first cylindrical shaft and connected to the inner rotor;
a second inner shaft rotatably disposed inside the second cylindrical shaft and connected to a pulsator inside the washing tub; and
a planetary gear set comprising: a ring gear fixedly coupled to the first cylindrical outer shaft and the second cylindrical outer shaft; a sun gear fixedly coupled to the first inner shaft; a plurality of planetary gears rotatably engaged with an outer surface of the sun gear and an inner surface of the ring gear; and a carrier coupled to the second inner shaft and rotatably supporting the planetary gears,
wherein the planetary gear set is configured in such a way that, when a rotational force from the inner rotor is applied to the sun gear through the first inner shaft, a rotational speed of the inner rotor is decelerated through the planetary gears and is transmitted to the pulsator through the carrier and the second inner shaft; and, when a rotational force from the outer rotor is applied to the ring gear through the first cylindrical outer shaft, a rotational speed of the outer rotor is not decelerated and is transmitted to the washing tub through the ring gear and the second cylindrical outer shaft, thereby being able to rotate the pulsator and the washing tub in the decelerated speed and the non-decelerated speed, respectively, and in opposite directions to each other.

2. The washing machine driving apparatus of claim 1 , wherein a first bearing is supported on an outer surface of the first cylindrical outer shaft and a second bearing is supported on an outer surface of the second cylindrical outer shaft, and
wherein the first bearing is mounted on a first bearing housing and the second bearing is mounted on a second bearing housing.

3. The washing machine driving apparatus of claim 2 , wherein edge portions of the first and second bearing housings overlap each other and are fixed to an outer tub disposed outside the washing tub.

4. The washing machine driving apparatus of claim 2 , wherein the planetary gear set is disposed between the first bearing and the second bearing.

5. The washing machine driving apparatus of claim 1 , wherein the inner rotor comprises:
a first magnet disposed with a certain gap from an inner surface of the double stator;
a first back yoke disposed on a rear surface of the first magnet; and
an inner rotor support to one end of which the first magnet and the first back yoke are fixed, and the other end of which is connected to the first inner shaft, wherein the inner rotor support is integrally formed with the first magnet and the first back yoke by insert molding.

6. The washing machine driving apparatus of claim 1 , wherein the outer rotor comprises:
a second magnet disposed with a certain gap from an outer surface of the double stator;
a second back yoke disposed on a rear surface of the second magnet; and
an outer rotor support to one end of which the second magnet and the second back yoke are fixed, and the other end of which is connected to the first cylindrical outer shaft, wherein the outer rotor support is integrally formed with the second magnet and the second back yoke by insert molding.

7. The washing machine driving apparatus of claim 1 , wherein the double stator comprises: a plurality of stator cores that are made of a split type and assembled and arranged in an annular form; bobbins that are wrapped on respective outer circumferential surfaces of the plurality of stator cores; a first coil wound on one side of each of the stator cores; a second coil wound on the other side of each of the stator cores; and a stator support in which the plurality of stator cores are arranged and integrated in an annular shape and that is fixed to a bearing housing.

8. The washing machine driving apparatus of claim 7 , wherein the stator support is integrally formed with the plurality of stator cores by insert molding.

9. A washing machine comprising:
the washing machine driving apparatus according to claim 1 :
an outer tub that accommodates wash water;
the washing tub rotatably disposed inside the outer tub to thus perform washing and dehydrating; and
the pulsator rotatably disposed inside the washing tub to thus form wash water flows.

10. The washing machine of claim 9 , wherein the pulsator and the washing tub of the washing machine are driven in different directions and at different speeds from each other, so as to form strong wash water flows in a pattern form.

11. The washing machine of claim 9 , wherein the pulsator and the washing tub of the washing machine are driven at an identical speed to each other, so as to form strong wash water flows to heighten a cleaning capability.

12. The washing machine of claim 10 , further comprising first and second bearings that are provided in the first cylindrical outer shaft and the second cylindrical outer shaft, respectively.

Assignees

• Amotech Co Ltd

Inventors

• Kim Byung Soo
• Ko Hyung Hwan

Classifications

• D06F37/40 Primary

  for driving the receptacle and an agitator or impeller, e.g. alternatively {(D06F37/304, D06F37/308 take precedence)} · CPC title

• D06F37/304

  Arrangements or adaptations of electric motors · CPC title

• D06F37/36

  for rotating the receptacle at more than one speed {(D06F37/304, D06F37/308 take precedence)} · CPC title

• D06F34/10

  Power supply arrangements, e.g. stand-by circuits · CPC title

• D06F2105/48

  Drum speed · CPC title