Washing machine and control method of washing machine

Patent metadata

Field	Value
Publication number	US-11725330-B2
Application number	US-202117465302-A
Country	US
Kind code	B2
Filing date	Sep 2, 2021
Priority date	Feb 23, 2018
Publication date	Aug 15, 2023
Grant date	Aug 15, 2023

Abstract

A washing machine includes: a tub; a drum; an induction heater disposed in a position spaced apart from the drum and configured to heat the drum; an input power source; a relay configured to interrupt a current applied to the coil of the induction heater from the input power source; a first processor configured to control the relay; and a safety device connected to a circuit connecting the first processor and the relay. The safety device includes: a first thermostat configured to operate according to a temperature of a first air between the drum and the tub, and open the circuit when the temperature of the first air is a first safety control temperature; and a thermal fuse configured to operate according to a temperature of a second air outside the tub, and open the circuit when the temperature of the second air is a second safety control temperature.

First claim

What is claimed is:

1. A washing machine comprising:
a tub configured to receive water;
a drum that is made of a metal material, that is disposed in the tub, and that is configured to rotate in the tub;
an induction heater spaced apart from the drum and configured to heat the drum;
an input power source configured to supply input power;
a relay connected electrically between the input power source and the induction heater and configured to apply the input power to the induction heater according to a control signal received from a first processor;
the first processor configured to provide the control signal to the relay;
at least one temperature sensor configured to detect a temperature of air between the drum and the tub; and
a first thermostat disposed between the relay and the first processor and configured to connect or disconnect the control signal from the first processor to the relay based on the temperature being in a first safety temperature range.

2. The washing machine of claim 1 , wherein a portion of the first thermostat is disposed between the drum and the tub.

3. The washing machine of claim 2 , wherein the first thermostat is configured to operate based on the temperature of air between the drum and the tub being equal to a first safety control temperature in the first safety temperature range.

4. The washing machine of claim 3 , wherein the first safety temperature range is between 190 and 200 degrees Celsius.

5. The washing machine of claim 1 , wherein the relay is configured to disconnect the input power source and the induction heater based on the relay not receiving the control signal from the first processor.

6. The washing machine of claim 1 , wherein the input power comprises an alternating current (AC) power, and
wherein the washing machine further comprises:
a rectifier configured to rectify the AC power transmitted through the relay; and
a switching element configured to switch an output of the rectifier and supply the output of the switching element to the induction heater.

7. The washing machine of claim 6 , wherein the washing machine further comprises a second processor configured to be controlled by the first processor and to control operation of the switching element based on the control of the first processor.

8. The washing machine of claim 1 , further comprising:
a second thermostat disposed outside the tub and configured to connect or disconnect the control signal from the first processor to the relay based on a heat temperature of the induction heater.

9. The washing machine of claim 8 , further comprising:
a thermal fuse configured to connect or disconnect the control signal from the first processor to the relay based on a temperature of air outside the tub being greater than or equal to a safety control temperature.

10. The washing machine of claim 9 , wherein the safety control temperature is in a second safety temperature range, the second safety temperature range being greater than the first safety temperature range.

11. The washing machine of claim 10 , wherein the second safety temperature range is between 220 and 240 degrees Celsius.

12. The washing machine of claim 9 , wherein the thermal fuse comprises a wire configured to deform based on the temperature of air outside the tub being greater than or equal to the safety control temperature.

13. The washing machine of claim 9 , wherein the induction heater comprises:
a heater base fixed to the tub;
a coil fixed to an upper surface of the heater base; and
a heater cover coupled to the heater base and disposed at an upper side of the coil, and
wherein the first thermostat is spaced apart from a center of the coil by a certain distance in a circumferential direction of the drum and positioned on an outer edge of the coil when viewed from above the tub.

14. The washing machine of claim 13 , wherein the second thermostat is disposed at the heater cover and spaced apart from the coil.

15. The washing machine of claim 13 , wherein the thermal fuse is spaced apart from the coil.

16. The washing machine of claim 15 , wherein at least a part of the thermal fuse overlaps with the coil when viewed from above the tub.

17. The washing machine of claim 15 , wherein the thermal fuse is in contact with a bottom surface of the heater base.

18. The washing machine of claim 15 , wherein the thermal fuse is disposed between the heater base and the tub and is in contact with the tub.

19. The washing machine of claim 1 ,
wherein the first processor is configured to control the induction heater within a preset control temperature range based on the temperature detected by the at least one temperature sensor.

20. The washing machine of claim 1 , wherein the first thermostat comprises a bimetal that comprises a pair of alloy plates having different expansion coefficients.

Assignees

• Lg Electronics Inc

Inventors

• Kim Beomjun
• Kim Woore
• Hong Sangwook

Classifications

• D06F39/04 Primary

  Heating arrangements · CPC title

• D06F33/00

  Control of operations performed in washing machines or washer-dryers  (D06F31/00 takes precedence; details of control systems therefor D06F34/00; control of operations performed in domestic laundry dryers D06F58/32) · CPC title

• D06F34/08

  Control circuits or arrangements thereof · CPC title

• D06F34/28

  Arrangements for program selection, e.g. control panels therefor; Arrangements for indicating program parameters, e.g. the selected program or its progress · 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