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EP-4074877-B1 - LAUNDRY TREATMENT APPARATUS AND METHOD OF CONTROLLING THE SAME

EP4074877B1EP 4074877 B1EP4074877 B1EP 4074877B1EP-4074877-B1

Inventors

  • JANG, JAEHYUK
  • NOH, HYUNWOO
  • KIM, CHANGOH
  • KIM, WOO RE
  • HONG, SANGWOOK

Dates

Publication Date
20260513
Application Date
20180809

Claims (13)

  1. A laundry treatment apparatus comprising: a tub (200); a drum (300) disposed within the tub (200) and configured to accommodate laundry therein, the drum (300) being made of a metal material; an induction module (400) arranged on an outer peripheral surface of an upper portion of the tub (200) and configured to heat the drum (300) via induction using a magnetic field; a lifter (50) that is provided in the drum (300); and a module controller (20) comprising at least one processor, wherein the module controller (20) is configured to control an output of the induction module (400) to control an amount of heat generated at the circumferential surface of the drum (300), characterized in that the induction module (400) is configured to: be turned on based on a rotational speed of the drum (300) reaching a threshold revolutions per minute, RPM, after the drum (300) starts to rotate, and be turned off based on the rotational speed of the drum (300) falling to less than the threshold RPM, wherein the threshold RPM is less than a tumbling RPM for a tumbling driving of the drum (300).
  2. The laundry treatment apparatus according to claim 1, wherein the threshold RPM is 30 RPM.
  3. The laundry treatment apparatus according to claim 1, wherein the induction module (400) is configured to be turned on or off based on the rotational speed of the drum (300) when the drum (300) operates in a tumbling driving period.
  4. The laundry treatment apparatus according to claim 1, further comprising: at least one magnet (80) provided at a position circumferentially spaced apart from the at least one lifter (50) by a predetermined angle on the drum (300), and a sensor (85) provided on the tub (200) and configured to sense the at least one magnet, wherein a position of the at least one lifter (50) is determined based on a position of the at least one magnet sensed by the sensor (85).
  5. The laundry treatment apparatus according to claim 4, wherein the driving of the induction module (400) is turned on or off by the module controller (20) repeatedly while the drum (300) is being driven.
  6. The laundry treatment apparatus according to claim 5, wherein the induction module (400) is configured to be turned off at a point in time at which the at least one lifter (50) faces the induction module (400) while the drum (300) is being driven.
  7. The laundry treatment apparatus according to claim 6, wherein the induction module (400) is configured to be turned on when the at least one lifter (50) deviates from a range at which the at least one lifter (50) faces the induction module (400) while the drum (300) is being driven.
  8. The laundry treatment apparatus according to claim 7, wherein a position of the at least one lifter (50) is determined based on a rotation angle of the drum (300).
  9. The laundry treatment apparatus according to claim 4, wherein a drum heating amount of the induction module (400) is reduced at a position at which the at least one lifter (50) faces the induction module (400).
  10. The laundry treatment apparatus according to claim 9, wherein the drum heating amount of the induction module (400) is increased at a position at which the at least one lifter (50) deviates from the position at which the at least one lifter (50) faces the induction module (400).
  11. The laundry treatment apparatus according to claim 10, wherein the drum heating amount of the induction module (400) is not reduced although the position at which at least one lifter (50) faces the induction module (400) when a rotational speed of the drum (300) exceeds a predetermined speed.
  12. The laundry treatment apparatus according to claim 11, wherein the predetermined speed of the drum (300) is 200 RPM.
  13. The laundry treatment apparatus according to claim 11, wherein a position of the at least one lifter (50) is determined based on a rotation angle of the drum (300).

Description

BACKGROUND OF THE INVENTION Field of the Invention The present invention relates to a laundry treatment apparatus, which directly heats a drum accommodating laundry therein, and which is enhanced in efficiency and safety. Discussion of the Related Art A laundry treatment apparatus is an apparatus for treating laundry and has functions to wash, dry, and refresh laundry. There are various types of laundry treatment apparatuses, such as a washing machine that is mainly for washing laundry, a washing machine that is mainly for drying, and a refresher that is mainly for refreshing. Then, there is a laundry treatment apparatus capable of performing at least two laundry treatments among washing, drying, and refreshing. For example, a single washing and drying machine may perform all of washing, drying, and refreshing. In recent years, there has been provided a laundry treatment apparatus that incorporates two treatment apparatuses so that the two treatment apparatuses perform washing at the same time, or perform washing and drying at the same time. The laundry treatment apparatus may generally include a heating device that heats wash water or air. Heating of the wash water may be performed to raise the temperature of wash water so as to promote activation of a detergent and accelerate decomposition of contaminants, thereby enhancing washing performance. Heating of the air may be performed to dry wet laundry by applying heat to the wet laundry so as to evaporate moisture. In general, the heating of the wash water is performed via an electric heater, which is mounted on a tub in which the wash water is accommodated. The electric heater is immersed in the wash water, and the wash water includes foreign substances and detergents. Therefore, foreign substances, such as scale, may accumulate on the electric heater, which may degrade the performance of the electric heater. In addition, the heating of the air requires a separate element, such as a fan for forcibly generating movement of the air and a duct for guiding the movement of the air. For example, an electric heater or a gas heater may be used for heating the air. In general, the efficiency of such an air heating method is not high. In recent years, there has been provided a drying machine for heating air using a heat pump. The heat pump utilizes the cooling cycle of an air conditioner in reverse, and thus requires the same elements as those of an air conditioner, namely an evaporator, a condenser, an expansion valve, and a compressor. Unlike the air conditioner in which a condenser is used in an indoor unit to lower the temperature of indoor air, the drying machine using the heat pump is configured to dry laundry by heating air in an evaporator. However, such a drying machine using the heat pump has a complicated configuration and increased manufacturing costs, which is problematic. In such a variety of laundry treatment apparatuses, an electric heater, a gas heater, and a heat pump, which serve as a heating device, have advantages and disadvantages, respectively, and concepts for a laundry treatment apparatus that uses induction heating as a new heating method capable of further highlighting the advantages of the aforementioned devices and compensating for the disadvantages thereof have been provided (Japanese Patent Registration No. JP2001070689 and Korean Patent Registration No. KR10-922986). However, the related art discloses only basic concepts for performing induction heating in a washing machine, and does not propose specific constituent elements of an induction heating module, connections or operational relationships with basic constituent elements of the laundry treatment apparatus, or specific methods and configurations for enhancing efficiency and securing safety. Therefore, it is necessary to provide a variety of specific technical ideas for enhancing efficiency and securing safety of the laundry treatment apparatus to which an induction heating principle is applied. DE 10 2008 043281 (A1) relates to a domestic appliance for the care of items of laundry, with a drum for receiving the items of laundry and a heating device for heating the items of laundry and/or the washing suds. SUMMARY OF THE INVENTION Accordingly, the present invention is directed to a laundry treatment apparatus that substantially obviates one or more problems due to limitations and disadvantages of the related art. It is an object of the present invention to provide a laundry treatment apparatus that is enhanced in efficiency and safety while using induction heating. According to an embodiment of the present invention, it is an object to provide a laundry treatment apparatus that effectively prevents overheating from occurring in a lifter provided in a drum, thereby enhancing safety and a method of controlling the same. In particular, it is an object to provide a laundry treatment apparatus that faithfully maintains the basic functions of a lifter and enhances stability and a method