INDUCTION HEATING APPLIANCE FOR COOKING

• US 20090314771A1
• Filed: 12/18/2007
• Published: 12/24/2009
• Est. Priority Date: 12/18/2006
• Status: Active Grant

• Current Assignee: Panasonic Intellectual Property Management Co., Ltd. (Panasonic Holdings Corporation)
• Original Assignee: Panasonic Intellectual Property Management Co., Ltd. (Panasonic Holdings Corporation)
• Inventors: Yokono, Masahiro, Okada, Kazuichi
• Granted Patent: US 9,565,721 B2
• Time in Patent Office: Days
• US Class Current: 219/647
• CPC Class Codes: H05B 2213/07 Heating plates with temperature control means
• CPC Class Codes: H05B 6/062 for cooking plates or the like

Abstract

An infrared sensor for detecting infrared rays of light and a light emitting element are disposed below a light transmittable top plate, which has a hearing area for heating an article to be heated placed thereon, in juxtaposed fashion relative to each other, so that infrared rays of light radiated from the article to be heated may be guided towards the infrared sensor. A light guide portion is provided for guiding rays of flight, emitted from the light emitting element, towards a heating area of the top plate, and the rays of light emitted from the light emitting element and guided by the light guide portion are projected onto the top plate through an upper opening of the light guide portion so that such rays of light can be noticed with eyes within the heating area.

Claims

1-11. -11. (canceled)

12. An induction heating appliance for cooking which comprises:

a body;

a light transmittable top plate provided atop the body and having a heating area for heating an article to be heated with the latter placed thereon;

a heating coil disposed below the top plate in face-to-face relation with the heating area for generating magnetic fields necessary to induction heat the article to be heated;

an infrared sensor disposed below the top plate for detecting infrared rays of light;

a light emitting element disposed below the top plate;

a light guide portion for guiding the infrared rays of light, emitted from the article to be heated, towards the infrared sensor; and

a control means for controlling an output of the heating coil based on an output signal from the infrared sensor,

wherein the top plate is provided with an infrared incident region positioned immediately above an upper opening of the light guide portion to guide the infrared rays of light, emitted from the article to be heated, towards the light guide portion, and the infrared incident region is also positioned at a location inwardly of an outer periphery of the heating coil and on a straight line extending in a forward and rearward direction of the body and passing across a center of the heating coil, when viewed from above the body, or its proximity and offset forwardly from the center of the heating coil, so that rays of light emanating from the light emitting element are emitted within the infrared incident region to allow the rays of light to be noticed within the heating area when viewed from above the body.

13. The induction heating appliance for cooking as claimed in claim 12, wherein in pace of the arrangement, in which the light emitted from the light emitting element is caused to illuminate within the infrared incident region and such light is noticeable within the heating area when viewed from above the body, the light emitted from the light emitting element is caused to illuminate in proximity to the infrared incident region and such light is noticeable within the heating area when viewed from above the body.

14. The induction heating appliance for cooking as claimed in claim 12, wherein the infrared incident region is provided only at one location inwardly of the outer periphery of the heating coil.

16. The induction heating appliance for cooking as claimed in claim 12, wherein when viewed from above the body, the infrared incident region has a center arranged on a straight line passing across a center of the heating coil and a center of a light emitting portion, which is a region where the light emitted from the light emitting element can be noticed, or its vicinity and between the center of the heating coil and the center of the light emitting portion.

17. The induction heating appliance for cooking as claimed in claim 16, wherein there is further provided a light guide element, upon which the light from the light emitting element is incident and which has a light emitting surface illuminated in an annular shape, and the light from the light emitting element is guided from the light emitting surface of the light emitting element towards the light guide portion.

18. The induction heating appliance for cooking as claimed in claim 17, wherein the infrared rays of light radiated from the article to be heated is guided towards the infrared sensor through the opening after having passed through a through-hole formed inside the light emitting surface.

19. The induction heating appliance for cooking as claimed in claim 16, wherein the infrared sensor and the light emitting element altogether form a sensor unit, and the sensor unit includes a printed circuit board for fixing and electrically connecting the infrared sensor and the light emitting element, a housing made of an electroconductive metallic material and accommodating therein the printed circuit board, and wherein the housing has a lower extension tube extending towards the infrared sensor and the light emitting element, with the infrared sensor and the light emitting element being accommodated within the lower extension tube.

20. The induction heating appliance for cooking as claimed in claim 19, further comprising a light diffusing ring having a through-hole above the infrared sensor and the light emitting element, wherein the infrared sensor is arranged below the through-hole.

23. The induction heating appliance for cooking as claimed in claim 13, wherein the infrared incident region is provided only at one location inwardly of the outer periphery of the heating coil.

24. The induction heating appliance for cooking as claimed in claim 13, wherein when viewed from above the body, the infrared incident region has a center arranged on a straight line passing across a center of the heating coil and a center of a light emitting portion, which is a region where the light emitted from the light emitting element can be noticed, or its vicinity and between the center of the heating coil and the center of the light emitting portion.

15. An induction heating appliance for cooking which comprises:

a body;

a light transmittable top plate provided atop the body and having a heating area for heating an article to be heated with the latter placed thereon;

a heating coil disposed below the top plate in face-to-face relation with the heating area for generating magnetic fields necessary to induction heat the article to be heated;

an infrared sensor disposed below the top plate for detecting infrared rays of light;

a light emitting element disposed below the top plate;

a light guide portion for guiding the infrared rays of light, emitted from the article to be heated, towards the infrared sensor; and

a control means for controlling an output of the heating coil based on an output signal from the infrared sensor,

wherein the top plate is provided with an infrared incident region positioned at a location inwardly of an outer periphery of the heating coil and offset from a center of the heating coil to guide the infrared rays of light, emitted from the article to be heated, towards the light guide portion, so that rays of light emanating from the light emitting element are emitted within the infrared incident region to allow the rays of light to be noticed within the heating area when viewed from above the body, and

wherein the light guide portion guides the light, emitted from the light emitting element, towards the infrared incident region, and the infrared incident region is partly or entirely noticeable when the light emitted from the light emitting element and guided within the light guide portion is projected towards the top plate through an opening of the light guide portion.

21. An induction heating appliance for cooking which comprises:

a body;

a light transmittable top plate provided atop the body and having a heating area for heating an article to be heated with the latter placed thereon;

a heating coil disposed below the top plate in face-to-face relation with the heating area for generating magnetic fields necessary to induction heat the article to be heated;

an infrared sensor disposed below the top plate for detecting infrared rays of light;

a light emitting element disposed below the top plate;

a light guide portion for guiding the infrared rays of light, emitted from the article to be heated, towards the infrared sensor; and

a control means for controlling an output of the heating coil based on an output signal from the infrared sensor,

wherein the top plate is provided with an infrared incident region positioned immediately above an upper opening of the light guide portion at a location inwardly of an outer periphery of the heating coil and offset from the center of the heating coil to guide the infrared rays of light, emitted from the article to be heated, towards the light guide portion, so that rays of light emanating from the light emitting element are emitted in proximity to the infrared incident region to allow the rays of light to be noticed within the heating area when viewed from above the body, and

wherein there is further provided a second light guide portion separated from the light guide portion by a light shielding wall, and the light emitted from the light emitting element travels through the second light guide portion to illuminate a light diffusing layer formed in proximity to the infrared incident region.

22. An induction heating appliance for cooling which comprises:

a body;

a light transmittable top plate provided atop the body and having a heating area for heating an article to be heated with the latter placed thereon;

a heating coil disposed below the top plate in face-to-face relation with the heating area for generating magnetic fields necessary to induction heat the article to be heated;

an infrared sensor disposed below the top plate for detecting infrared rays of light;

a light emitting element disposed below the top plate;

a light guide portion for guiding the infrared rays of light, emitted from the article to be heated, towards the infrared sensor; and

a control means for controlling an output of the heating coil based on an output signal from the infrared sensor,

wherein the top plate is provided with an infrared incident region positioned immediately above an upper opening of the light guide portion at a location inwardly of an outer periphery of the heating coil and offset from the center of the heating coil to guide the infrared rays of light, emitted from the article to be heated, towards the light guide portion, so that rays of light emanating from the light emitting element are emitted within or in proximity to the infrared incident region to allow the rays of light to be noticed within the heating area when viewed from above the body, and

wherein the infrared incident region is arranged, when viewed from above the body, on a straight line passing across the center of the heating coil and a center of the light emitting portion, which is a region at which the rays of light emitted from the light emitting element are noticeable, or its vicinity and between the center of the heating coil and the center of the light emitting portion.