Laundry treating apparatus having induction heater

Patent metadata

Field	Value
Publication number	US-11891742-B2
Application number	US-202217580070-A
Country	US
Kind code	B2
Filing date	Jan 20, 2022
Priority date	Jan 10, 2019
Publication date	Feb 6, 2024
Grant date	Feb 6, 2024

Abstract

A laundry treating apparatus includes a tub, a drum for receiving an object therein, an induction heater for heating an outer circumferential face of the drum, a motor for rotating the drum, and a power supply for supplying power from an external power source to the laundry treating apparatus, a relay for interrupting current to be applied from the power supply to the induction heater via an electrical wire, a processor connected to the relay via a control wire and configured to control an operation of the relay and to control an operation of the induction heater and an operation of the motor, and a first safety device disposed at the control wire to interrupt a control signal to be applied from the processor to the relay. The first safety device operates in response to a temperature change thereof.

First claim

What is claimed is:

1. An object treating apparatus comprising:
a tub;
a drum rotatably disposed within the tub and configured to receive an object therein;
an induction heater disposed on the tub and configured to heat an outer circumferential surface of the drum facing the heater;
a first temperature sensor configured to detect a temperature of air in a space between the tub and the drum;
a second temperature sensor configured to sense a temperature of washing water in the tub or a temperature adjacent to condensed water in the tub; and
a processor configured to control an operation of the induction heater to heat the drum to heat and dry the object based on the temperature sensed by at least one of the first temperature sensor or the second temperature sensor,
wherein, when a temperature sensed by the first temperature sensor is equal to or greater than a first temperature, the processor is configured to control to stop the operation of the induction heater or to lower an output of the induction heater; or
wherein the processor is configured to perform repeatedly on and off of the operation of the induction heater in order to maintain the temperature detected by the first temperature sensor to the first temperature.

2. The object treating apparatus of claim 1 , wherein, when the second temperature sensor detects a second temperature while the induction heater heats washing-water to perform a washing cycle, the processor is configured to control to stop the operation of the induction heater or to lower an output of the induction heater.

3. The object treating apparatus of claim 2 , wherein the processor further configured to determine a drying ending timing based on the temperatures detected by the first temperature sensor and the second temperature sensor.

4. The object treating apparatus of claim 3 , wherein the processor further configured to determine the drying ending timing based on a difference (delta T) between a temperature detected by the first temperature sensor and a temperature detected by the second temperature sensor.

5. The object treating apparatus of claim 4 , wherein the processor further configured to define a first threshold value and stops a drying cycle when the difference between the temperature detected by the first temperature sensor and the temperature detected by the second temperature sensor is equal to or larger than the first threshold value; or
wherein the processor further configured to define a second threshold value which is obtained by subtracting the first threshold value from the first temperature and stops the drying cycle when the temperature detected by the second temperature sensor is equal to or smaller than the second threshold value.

6. The object treating apparatus of claim 5 , wherein the processor further configured to define the first threshold value based on a drying target load amount which is defined as a weight of a load to be dried.

7. The object treating apparatus of claim 6 , wherein the processor further configured to determine the drying target load amount during the drying cycle after the first temperature sensor detects the first temperature for the first time in the drying cycle.

8. The object treating apparatus of claim 7 , wherein the processor further configured to determine the drying target load amount based on a maximum value of the delta T as detected before the first temperature sensor senses the first temperature for the first time in the drying cycle.

9. The object treating apparatus of claim 7 , wherein the processor further configured to determine the drying target load amount based on a minimum value of the delta T as detected after the first temperature is sensed by the first temperature sensor for the first time in the drying cycle.

10. The object treating apparatus of claim 7 , wherein the processor further configured to determine the drying target load amount based on a time required to reach a maximum value of the delta T as detected before the first temperature sensor senses the first temperature for the first time in the drying cycle.

11. The object treating apparatus of claim 7 , wherein the processor further configured to determine the drying target load amount based on a time required to reach a minimum value of the delta T as detected after the first temperature is sensed by the first temperature sensor for the first time in the drying cycle.

12. The object treating apparatus of claim 1 , wherein the first temperature sensor is disposed at an upper portion of the tub and adjacent to the induction heater.

13. The object treating apparatus of claim 1 , wherein the first temperature sensor is positioned outside a projection region in which the induction heater vertically projects toward the drum.

14. The object treating apparatus of claim 1 , wherein the tub has a condensed water receiving portion having a recess defined downwards in a bottom of the tub, wherein the condensed water is contained in the condensed water receiving portion;
wherein the second temperature sensor is disposed close to the condensed water without being in contact with the condensed water.

15. The object treating apparatus of claim 14 , wherein the second temperature sensor is spaced, by a spacing of 10 mm to 15 mm from the bottom face of the condensed water receiving portion.

16. The object treating apparatus of claim 14 , wherein the second temperature sensor is spaced by a spacing of 12 mm from the bottom face of the condensed water receiving portion.

17. The object treating apparatus of claim 1 , further comprising:
a power supply configured to supply power from an external power source to the object treating apparatus;
a relay configured to apply or interrupt current flow from the power supply to the induction heater, wherein the relay is normally in an open state to thereby interrupt the current flow from the power supply to the induction heater;
wherein the processor further configured to control the relay by applying a control signal to the relay, the control signal causing the relay to switch from the open state to a closed state to thereby apply the current flow from the power supply to the induction heater.

18. The object treating apparatus of claim 17 , wherein, when the temperature sensed by the first temperature sensor is above the first temperature, the processor configured to cease active transmission of the control signal to the relay to stop the induction heater.

Assignees

• Lg Electronics Inc

Inventors

• Jang Jaehyuk
• Kim Beomjun
• Hong Sangwook

Classifications

• D06F34/10 Primary

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

• D06F34/24

  Liquid temperature · CPC title

• D06F37/42

  Safety arrangements, e.g. for stopping rotation of the receptacle upon opening of the casing door · CPC title

• D06F39/04

  Heating arrangements · CPC title

• D06F25/00

  Washing machines with receptacles, e.g. perforated, having a rotary movement, e.g. oscillatory movement, the receptacle serving both for washing and for centrifugally separating water from the laundry and having further drying means, e.g. using hot air  (control of washing or of washing and drying D06F33/00, D06F34/00; domestic laundry dryers D06F58/00) · CPC title