Laundry treatment apparatus and method of controlling the same

Patent metadata

Field	Value
Publication number	US-11519124-B2
Application number	US-202117316265-A
Country	US
Kind code	B2
Filing date	May 10, 2021
Priority date	Aug 9, 2017
Publication date	Dec 6, 2022
Grant date	Dec 6, 2022

Abstract

A laundry treatment apparatus is configured to directly heat a drum containing laundry therein. The laundry treatment apparatus includes: a tub; a drum configured to rotate within the tub and to contain laundry therein, the drum being formed of a metallic material; and an induction module provided at an outer surface of the tub and configured to heat a surface of the drum within the tub via induction, the induction module comprising: a coil that comprises a wire through which an electric current is configured to pass so as to generate a magnetic field; a base housing configured to accommodate the coil therein, the base housing being mounted on the outer surface of the tub; an at least one magnet configured to be arranged above the base housing in which the coil is accommodated, and arranged to be lengthwise perpendicular to a longitudinal direction of the wire of the coil.

First claim

What is claimed is:

1. A laundry treatment apparatus comprising:
a tub;
a drum located in the tub and configured to rotate relative to the tub, the drum being made of a metallic material; and
an induction module located at an outer surface of the tub and configured to heat the drum via induction, the induction module comprising:
a coil that comprises a wire configured to generate a magnetic field, the coil having a front end portion, a rear end portion, and an intermediate portion located between the front end portion and the rear end portion, and
a plurality of permanent magnets comprising a plurality of first permanent magnets arranged at the front end portion or the rear end portion, and a plurality of second permanent magnets arranged at the intermediate portion,

wherein a density of the plurality of first permanent magnets is greater than a density of the plurality of second permanent magnets.

2. The laundry treatment apparatus according to claim 1 , wherein a distance between adjacent first magnets among the plurality of first permanent magnets is less than a distance between adjacent second magnets among the plurality of second permanent magnets.

3. The laundry treatment apparatus according to claim 2 , wherein the plurality of permanent magnets comprise a plurality of bar magnets, each bar magnet having a same size.

4. The laundry treatment apparatus according to claim 1 , wherein the plurality of permanent magnets are identical to one another.

5. The laundry treatment apparatus according to claim 1 , wherein the front end portion of the coil is located at a front portion of the tub, and the rear end portion of the coil is located at a rear portion of the tub.

6. The laundry treatment apparatus according to claim 1 , further comprising:
a base housing that accommodates the coil and that is located on the outer surface of the tub.

7. The laundry treatment apparatus according to claim 6 , wherein a wire density of the wire in the intermediate portion is greater than a wire density of the wire in the front end portion or the rear end portion, the wire density being defined as a ratio of an area of the wire to an area of the base housing.

8. The laundry treatment apparatus according to claim 6 , wherein the wire is located within the base housing, and
wherein the coil comprises:
a straight portion comprising a plurality of straight segments of the wire; and
a curved portion comprising a plurality of curved segments of the wire.

9. The laundry treatment apparatus according to claim 8 , wherein the straight portion of the coil comprises:
a horizontal straight portion comprising a front straight portion located at a front portion of the outer surface of the tub and a rear straight portion located at a rear portion of the outer surface of the tub; and
a vertical straight portion that extends perpendicular to the horizontal straight portion of the coil, and
wherein the curved portion of the coil is located between the horizontal straight portion of the coil and the vertical straight portion of the coil.

10. The laundry treatment apparatus according to claim 8 , wherein the plurality of second permanent magnets are arranged perpendicular to a part of the straight portion of the coil, and
wherein the plurality of first permanent magnets comprise:
curved portion magnets that are arranged along a radial direction of curvature of the curved portion of the coil, and
straight portion magnets that are arranged perpendicular to another part of the straight portion of the coil.

11. The laundry treatment apparatus according to claim 8 , wherein the curved portion of the coil comprises:
an inner coil portion arranged at an inner radial portion of the coil, the inner coil portion comprising a first subset among the plurality of curved segments of the wire; and
an outer coil portion arranged at an outer radial portion of the coil, the outer coil portion comprising a second subset among the plurality of curved segments of the wire, and
wherein a radius of curvature of the inner coil portion is equal to a radius of curvature of the outer coil portion.

12. The laundry treatment apparatus according to claim 6 , wherein the induction module further comprises a cover that is coupled to the base housing and that covers the coil.

13. The laundry treatment apparatus according to claim 12 , wherein the cover comprises a plurality of magnet mounting portions configured to mount the plurality of permanent magnets.

14. The laundry treatment apparatus according to claim 13 , wherein each of the plurality of magnet mounting portions is configured to accommodate one of the plurality of permanent magnets.

15. The laundry treatment apparatus according to claim 13 , wherein each of the plurality of magnet mounting portions comprises:
side walls that protrude downward from a bottom surface of the cover, the side walls defining a lower opening that accommodates at least one of the plurality of permanent magnets, and
wherein the at least one of the plurality of permanent magnets is exposed through the lower opening and faces the coil.

16. The laundry treatment apparatus according to claim 13 , wherein the base housing comprises a fixing rib that protrudes upward from the base housing toward the cover, the fixing rib defining a coil slot that receives the wire of the coil, and
wherein an upper end of the fixing rib is in contact with a lower end of one of the plurality of magnet mounting portions.

17. The laundry treatment apparatus according to claim 12 , wherein the base housing comprises a fixing rib that protrudes upward from the base housing toward the cover, the fixing rib defining a coil slot that receives the wire of the coil, and
wherein the cover comprises a plurality of reinforcing ribs that protrude downward from a bottom surface of the cover toward the base housing, the plurality of reinforcing ribs being in contact with an upper end of the fixing rib.

18. The laundry treatment apparatus according to claim 1 , wherein the induction module extends in a longitudinal direction, and the intermediate portion extends parallel to the longitudinal direction,
wherein the front end portion and the rear end portion extend in a width direction perpendicular to the longitudinal direction, and
wherein the wire is wound about a center area of the coil along the longitudinal direction and the width direction.

19. The laundry treatment apparatus according to claim 18 , wherein a length of the intermediate portion in the longitudinal direction is greater than a width of the front end portion or the rear end portion in the width direction.

20. The laundry treatment apparatus according to claim 18 , wherein a number of the plurality of first permanent magnets is greater than a number of the plurality of second permanent magnets.

Assignees

• Lg Electronics Inc

Inventors

• Kim Beomjun
• Park Bio
• Hong Sangwook

Classifications

• D06F39/04 Primary

  Heating arrangements · CPC title

• H05B6/108

  for heating a fluid · CPC title

• D06F2105/28

  Electric heating · CPC title

• D06F34/24

  Liquid temperature · CPC title

• H05B6/102

  the metal pieces being rotated while induction heated · CPC title