JP5372129B2 - Induction heating cooker - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an induction heating cooker that solves the problem occurring when many rod-like high permeability materials are arranged and the high permeability materials are densely arranged at the center in a radial direction of the heating coils such that an airflow path for the heating coils disappears thereby making it impossible to cool the heating coils. <P>SOLUTION: The induction heating cooker comprises circular heating coils 2 heating a cooking vessel and including a first coil body 21 provided at the center and a second coil body 22 provided on a circumference of the first coil body 21 leaving a ring-shaped gap, a drive circuit energizing the heating coils 2, and a plurality of high permeability materials 49 radially provided on one side of the heating coils 2. The high permeability material 49 has a recess part 49b on an upper part at a position just below the first coil body 21. <P>COPYRIGHT: (C)2012,JPO&amp;INPIT

Description

  The present invention relates to an induction heating cooker, and more particularly to an induction heating cooker in which the heat generation density in the radial direction of the heating coil is made uniform while ensuring the cooling performance of the heating coil.

  In an induction heating cooker such as an IH cooking heater or rice cooker, a circular heating coil is energized with an alternating current of several tens of kHz, and the cooking utensil is heated by a current flowing through a cooking utensil such as a pot or kettle made of a conductor. . In order to improve the heat generation efficiency for cooking utensils, a method of collecting high magnetic permeability members such as ferrite under the heating coil and collecting the magnetic flux generated by the heating coil is taken, but in order to minimize the amount of expensive ferrite In general, a plurality of rod-shaped ferrites are arranged along the radial direction. For example, there is an IH cooking heater in which a ferrite having a constant width along the radial direction is arranged in a cross shape and a central portion is a gap (see, for example, Patent Document 1). On the other hand, there is an IH rice cooker in which rod-like ferrites whose width is increased at a constant rate along the radial direction are arranged in a cross shape and the center is a gap (see, for example, Patent Document 2). Moreover, in FIG. 7 of the said patent document 1, in order to make the temperature distribution of a cooking appliance uniform, block-shaped ferrite with a fixed width | variety was divided and distributed to the center part vicinity and outermost periphery part with a low heat generation density. An example is shown.

JP 59-25194 (page 2, FIG. 1, FIG. 7) Japanese Patent Laying-Open No. 2003-332034 (first page, FIG. 3)

  When the width of the ferrite is made constant along the radial direction, for example, when the heat generation density in the radial direction of the bottom of the cooking utensil (pan) having a radius of 100 mm is calculated, as shown in the reference diagram of FIG. In the distance R = 0, the vicinity of the central portion and the vicinity of the outer peripheral portion are low, and the intermediate portion between the central portion and the outer peripheral portion is high. Therefore, it is conceivable to make the temperature distribution in the radial direction uniform by arranging as much ferrite as possible in the vicinity of the central portion and the outer peripheral portion to concentrate the magnetic flux. Although the overall heat generation efficiency is improved by the conventional technique shown in FIG. 1 of Patent Document 1, it is difficult to make the temperature distribution uniform because ferrite has a uniform cross section in the radial direction. In the prior art shown in FIG. 7 of Patent Document 1 above, ferrite is arranged in the vicinity of the central portion and the outer peripheral portion, so that a uniform temperature distribution can be expected, but the ferrite is divided in the radial direction. Since the width is uniform, the heat density distribution of the pan cannot be finely adjusted. In addition, since ferrite is dispersed and installed in many places, there is a problem that requires time for assembly.

  In the prior art disclosed in Patent Document 2, since the width of the ferrite becomes narrower as it approaches the central portion of R = 0 along the radial direction, the heat generation density distribution along the radial direction is the heat generation density. In the vicinity of R = 0 inside the peak, there was a problem that the heat generation density further decreased. For reference, in order to increase the heat generation efficiency by paying attention only to the heat generation efficiency at the center, as shown in the reference diagram of FIG. 18, a high permeability member 200 such as ferrite is used for the circular heating coil 100. There is also a problem that it is difficult to cool the heating coil 1 with such a configuration.

  The present invention has been made to solve the above-described problems of the prior art, and can improve the heat generation efficiency while uniforming the heat generation density distribution along the radial direction and cooling the central portion of the heating coil. It aims at providing the induction heating cooking appliance which can do.

An induction heating cooker according to the present invention includes a first coil body provided at the center and a second coil body disposed around the outer periphery of the first coil body via a ring-shaped gap. Induction heating cooking comprising a circular heating coil for heating a cooking utensil, a drive circuit for passing current to the heating coil, and a plurality of high permeability members arranged radially on one side of the heating coil The high-permeability member is disposed with a gap between the lower surface of the heating coil and the lower surface of the heating coil, and a recess is provided at an upper portion corresponding to a position directly below the first coil body. The space to be communicated with the gap is a cooling air passage .

In the present invention, the high magnetic permeability member is disposed through the clearance from the lower surface of the heating coil, and a recess is provided at an upper portion corresponding to a position directly below the first coil body, and is formed by the recess. The space is connected to the gap to provide a cooling air passage so that the heat generation efficiency is improved while optimizing the amount of the high magnetic permeability member, and the heat generation density distribution in the radial direction is made uniform, and the central portion of the heating coil in the radial direction. It is also possible to secure an air path for cooling the air.

Embodiment 1 FIG.
FIG. 1 is a diagram schematically illustrating a main part of an induction heating cooker according to Embodiment 1 of the present invention. FIG. 1 (a) is a rear view showing the shape of a high permeability member and the arrangement with respect to a heating coil. ) Is a plan view showing the high magnetic permeability member, and FIG. 2 is a side sectional view of FIG. In the figure, an induction heating cooker 1 includes a circular heating coil 2, a drive circuit 3 for supplying a high-frequency current to the heating coil 2, and a plurality of radial coils disposed on the back side (lower side) of the heating coil 2. (In this example, eight) are configured to include ferrite 4 as a high permeability member, and a space between adjacent ferrites 4 in the circumferential direction forms an air passage 5 for cooling the heating coil 2. Yes. A cooking utensil 6 such as a pot or a pot is placed on a top plate (not shown) provided on the top of the heating coil 2. In addition, since ferrite is generally used as the high magnetic permeability member, hereinafter, it is referred to as ferrite unless particularly distinguished.

  Each ferrite 4 has a substantially uniform thickness in a direction parallel to the central axis θ of the heating coil 2, and the innermost peripheral portion A and the intermediate portion B are narrow in the radial direction, that is, a small cross-sectional area portion. 4a and 4b are formed in the vicinity of the central part between the innermost peripheral part A and the intermediate part B. The first part is wider than the small cross-sectional area parts 4a and 4b, that is, has a larger cross-sectional area. The large cross-sectional area 4c is formed. The ferrite 4 is formed to be wide from the small cross-sectional area portion 4b of the intermediate portion B toward the outermost peripheral portion C, and the outermost peripheral portion C is also configured as a second large cross-sectional area portion 4d, for example, in a single rod shape. Is formed.

  Further, a predetermined gap 5a constituting the air path 5 is provided between the small cross-sectional areas 4a of the adjacent ferrites 4, and the air path 5 is radially secured from the outside to the center of the heating coil 2. Yes. The small cross-sectional area 4b of the intermediate part B is set at a position corresponding to the vicinity of the peak in the radial heat generation density distribution shown in FIG. 17, and the first large cross-sectional area 4c is closer to the central part than the first peak. The large sectional area portion 4d of 2 is provided so as to correspond to the outermost peripheral portion C position where the heat generation density is low. In this document, the intermediate part B means a part between the innermost peripheral part A and the outermost peripheral part C, and is not limited to a position in the vicinity of a half in dimension. Other configurations are the same as those of the conventional apparatus.

  Next, the operation of the first embodiment configured as described above will be described. When a high frequency current is applied to the heating coil 2 by the drive circuit 3, a magnetic flux is generated around the heating coil 2, but since the ferrite 4 is installed in the vicinity of the heating coil 2, induction magnetization occurs in the ferrite 4, As a result, the magnetic flux passing through the ferrite 4 increases, the magnetic circuit of the ferrite 4 part becomes low resistance, the magnetic flux entering the cooking utensil 6 also increases, the eddy current generated increases, and the heating density and heating efficiency of the cooking utensil 6 increase. Will also increase.

  In the first embodiment, the first large cross-sectional area portion 4c formed by expanding the width of the ferrite 4 is positioned in the vicinity of the innermost peripheral portion A, and the second large cross-sectional area portion 4d is positioned in the outermost peripheral portion C. In this manner, the radial arrangement on the lower surface of the heating coil 2 improves the heat generation density at the portion where the heat generation density is reduced as shown in FIG. Is done. Further, in the vicinity of the center portion of the heating coil 2, since the gap 5 a exists between the adjacent ferrites 4, the improvement in the magnetic flux density by the ferrite 4 is slightly sacrificed. Necessary cooling is performed on the heating coil 2 by securing the leading air passage 5.

  As described above, according to the first embodiment, the heat generation density distribution in the radial direction with respect to the cooking utensil 6 is made uniform while increasing the heating efficiency, and the air passage 5 of the heating coil 2 can be secured, thereby cooling the heating coil 2. Can be obtained. Since the temperature distribution of the cooking utensil 6 is made constant along the radial direction, the food can be heated uniformly. Moreover, the amount of expensive ferrite can be reduced by narrowing the width of the intermediate portion B of the ferrite 4 in the radial direction where the heat generation density is high. Further, since the integrally formed ferrite 4 having the same shape may be disposed in the radial direction, the configuration is simple and the assembly can be facilitated. Note that the ferrite 4 is not necessarily limited to an integral one, and even a divided one can increase the uniform heat generation density distribution and improve the cooling of the heating coil 2.

Embodiment 2. FIG.
FIG. 3 schematically shows a main part of an induction heating cooker according to Embodiment 2 of the present invention, in which (a) is a rear view showing a high permeability member and a heating coil, and (b) is a side sectional view. It is. In the second embodiment, the width of the cross-sectional area of the ferrite 4 is changed along the radial direction in the first embodiment, whereas the cross-sectional area is changed in the radial direction by changing the thickness. That is, the planar shape of the ferrite 41 is formed with a constant width outside the intermediate portion B in the radial direction of the heating coil 2, and is tapered from the center of the intermediate portion B to the innermost peripheral portion A.

  The thickness of the ferrite 41 is slightly closer to the outer peripheral portion of the innermost peripheral portion A as shown in FIG. 3B, and the intermediate portion B is thin. As a small cross-sectional area portion 41a and a small cross-sectional area portion 41b, respectively. The outermost peripheral portion C and the outermost peripheral portion C are thick, and a large cross-sectional area portion 41c and a large cross-sectional area portion 41d are formed, respectively. In this example, the tip end portion 41e of the innermost peripheral portion A is also formed thick, but since the width is narrow, the cross-sectional area is not necessarily large. Although the adjacent ferrites 41 are almost in contact with each other at the innermost peripheral portion A in the drawing, the air path can be widened by providing a gap as in the first embodiment. Other configurations are the same as those in the first embodiment.

  In the second embodiment configured as described above, similarly to the first embodiment, the ferrite 41 has a cross-sectional area in the vicinity of the innermost peripheral portion A where the heat generation density is low and in the vicinity of the outermost peripheral portion C. By increasing the thickness and increasing the thickness at a position near the intermediate portion B where the heat generation density reaches a peak, the effect of making the heat generation density distribution uniform can be obtained as in the case of increasing the width of the ferrite. . Moreover, an air path can also be secured. Moreover, the heating efficiency in the vicinity of R = 0 can be improved by increasing the thickness of the tip portion 41e near the innermost peripheral portion A where the heating efficiency deteriorates. In addition, when the radius is large, the length along the circumferential direction becomes long, the thickness increases in a wide area, and interference with a circuit board (not shown) and mounted devices may be a problem. Therefore, it may be combined with a method of widening the width of the ferrite 41. Further, in the vicinity of the center in the vicinity of R = 0, the ratio of the portion where the ferrite 41 protrudes downward is small, and interference with equipment such as a substrate hardly occurs.

Embodiment 3 FIG.
4 is a side cross-sectional view schematically showing a main part of an induction heating cooker according to Embodiment 3 of the present invention. In the figure, the ferrite 42 disposed at the lower portion of the heating coil 2 includes a first high magnetic permeability material 42a that can be obtained at a low cost at a general level, and the magnetic permeability disposed on the outer peripheral side from the intermediate portion. The first high magnetic permeability material 42a is formed of a second high magnetic permeability material 42b having a higher magnetic permeability disposed adjacent to the central portion of the first high magnetic permeability material 42a, and the first high magnetic permeability material 42a has a cross-sectional area. In conversion, the heat generation density distribution is made uniform by changing the width in the radial direction of the heating coil 2 in the same manner as in the first embodiment.

  In the third embodiment configured as described above, the portion in which the cross-sectional area is increased by increasing the width and thickness of the ferrite in the first or second embodiment is replaced with the second high permeability. By using the magnetic material 42b, the resistance is reduced, and the distribution of heat generation density is made uniform while securing the air passage for cooling the heating coil 2 in the innermost peripheral portion A. In addition to the same effects as those of the first or second aspect, the second high magnetic permeability material 42b having a higher magnetic permeability can be used to suppress an increase in thickness, thereby reducing the size of the apparatus. Can also be obtained. Needless to say, the arrangement position of the second high magnetic permeability material 42b having a higher magnetic permeability is not limited to that illustrated in FIG. For example, the second high magnetic permeability material 42b is added to the outermost peripheral portion C, or the portion corresponding to the outermost peripheral portion C of the first high magnetic permeability material 42a is replaced with the second high magnetic permeability material 42b. May be.

Embodiment 4 FIG.
FIG. 5 is a side sectional view schematically showing a main part of an induction heating cooker according to Embodiment 4 of the present invention, and FIG. 6 is a side sectional view showing a modification thereof. In FIG. 5, the ferrite 43 is composed of a first portion 43a located on the outer peripheral side from the intermediate portion B, and a second portion 43b adjacent to the central portion side of the first portion 43a via a stepped portion, A gap 51 communicating with the air passage 5 (not shown) is formed between the second portion 43 b and the lower surface of the heating coil 2. Other configurations are the same as those of the first embodiment.

  In the fourth embodiment, the cooling air is passed through a large gap 51 formed between the ferrite 43 and the heating coil 2 in the vicinity of R = 0 in the innermost peripheral portion A, whereby the central portion of the heating coil 2 is Cooling more efficiently, for example, the possibility of insufficient cooling efficiency can be solved by concentrating the ferrites 4 as in the first embodiment. As shown in the modification of FIG. 6, the thickness of the second portion 43c adjacent to the central portion of the first portion 43a via the stepped portion is increased, or a material having a higher magnetic permeability is used. Thereby, the deterioration of the heating efficiency by having increased the distance with the heating coil 2 can also be prevented.

Embodiment 5 FIG.
FIGS. 7 to 10 illustrate the main part of an induction heating cooker according to Embodiment 5 of the present invention. FIG. 7 is a rear view schematically showing a high permeability member and a heating coil portion, and FIG. FIG. 9 is a side sectional view, FIG. 9 is a view showing the heat generation density at the bottom of the cooking utensil in the configuration shown in FIG. 7, and FIG. 10 is a rear view showing a modification of FIG. In the figure, the heating coil 2 has a circular first coil body 21 disposed in the center, and a second coil coil disposed around the outer periphery of the first coil body via a circular ring-shaped gap D. In the gap D, a plurality of temperature sensors 7 for detecting the temperature of the cooking utensil 6 are provided. The ferrite 44 has a substantially constant thickness and is formed with a large cross-sectional area 44a that is widened at a position corresponding to the gap D in the radial direction.

  The result of analyzing and calculating the temperature distribution of the cooking utensil 6 in the above configuration is shown in FIG. From FIG. 9, the magnetic field of the heating coil 2 is low and the heat generation efficiency is lowered at the position corresponding to the middle part B of the cooking utensil 6 immediately above the gap D part that is divided into two and has no coil. By arranging 44a so as to correspond to the gap D portion, the heat generation efficiency in this portion is improved, and the temperature distribution of the cooking utensil 6 is improved. 10 is similar to the example of FIG. 1 in that the cross-sectional area of the ferrite 45 corresponding to the portion where the heat generation density of the outermost peripheral portion C of the heating coil 2 is low is the same as that of the example of FIG. As a result, the heat generation efficiency at the outermost peripheral portion shown in FIG. 9 can be improved. As a result, a more uniform distribution can be obtained in the overall radial direction. Further, since the cross-sectional area of the portion having a high heat generation density is configured to be small, the amount of ferrite can be minimized and the cost can be reduced. It goes without saying that instead of increasing the width of the ferrite 44 or 45, the thickness may be increased, or a combination of both may be used.

Embodiment 6 FIG.
FIG. 11 is a partial cross-sectional view showing a main part of an induction heating cooker according to Embodiment 6 of the present invention. In the figure, the heating coil 2 is divided into two via a gap D in the radial direction as in the fifth embodiment shown in FIG. The ferrite 46 is formed with a large cross-sectional area 46a that is partially thick so as to enter the gap D where the heat generation density decreases. Other configurations are the same as those of the fifth embodiment. In general, ferrite has a higher effect of collecting magnetic flux as its cross-sectional area is larger, but the effect becomes smaller as the distance from the cooking utensil 6 is increased. For example, the magnetic field generated by the magnetic moment in ferrite decreases in proportion to the third power of the magnetic moment position. Therefore, it is more effective to arrange the ferrite as close to the cooking utensil 6 as possible. In the sixth embodiment, since the large cross-sectional area 46a is configured close to the cooking utensil 6 so as to enter the gap D between the first coil body 21 and the second coil body 22, the heat generation efficiency is improved. The improvement effect is high, and the temperature distribution in the radial direction can be made more uniform. For example, it may be configured in combination with the fifth embodiment.

Embodiment 7 FIG.
12 and 13 schematically illustrate the main part of an induction heating cooker according to Embodiment 7 of the present invention. FIG. 12 is a rear view schematically showing a high permeability member and a heating coil portion. 13 is a view corresponding to a cross-sectional view taken along line XIII-XIII in FIG. In the figure, the heating coil 2 is divided into two via the gap D in the radial direction as in the fifth embodiment shown in FIG. 7, and a plurality of similar temperature sensors 7 are provided in the gap D. The ferrite 47 is arranged radially in the radial direction of the heating coil 2 and is adjacent to the gap D in a rod-like ferrite body 47a formed with the same width except that it is tapered from the vicinity of the center toward the center. Block-like high magnetic permeability members 47b installed between the ferrite main bodies 47a.

  In the seventh embodiment configured as described above, the heating coil 2 is provided by arranging the block-like high permeability member 47b that concentrates the magnetic flux in the region of the gap D of the two-divided coil where the heat generation density distribution deteriorates. The temperature distribution in the radial direction can be made uniform. In addition, this gap D portion is a position where the coil body does not exist, and therefore the coil body does not need to be cooled, and since it is an intermediate portion between the center and the outermost periphery, the circumferential space is accordingly large. It is also possible to arrange a large number of the high magnetic permeability members 47b close to the cooking utensil 6, and the temperature distribution can be easily made uniform. Moreover, the problem of deterioration of heating coil 2 cooling does not arise. Although the width of the ferrite main body 47a is constant along the radial direction, the portion corresponding to the gap D and the outermost peripheral portion C may be formed wide as shown in FIG.

Embodiment 8 FIG.
14 and 15 schematically illustrate the main part of an induction heating cooker according to Embodiment 8 of the present invention. FIG. 14 is a rear view schematically showing a high magnetic permeability member and a heating coil portion. 15 is a view corresponding to a cross-sectional view taken along line XV-XV in FIG. In the eighth embodiment, the increase in cross-sectional area corresponding to the block-shaped high magnetic permeability member 47b shown in the seventh embodiment is integrated with the ferrite body 48a and protrudes upward so as to enter the gap D. The large cross-sectional area portion 48b is configured. As a result, the large cross-sectional area 48b of the ferrite 48 is closer to the cooking utensil 6 at the position of the gap D without increasing the number of the ferrites 48, so that the assembly is easy, the heat generation efficiency is further improved, and the temperature along the radial direction is increased. Distribution can be made uniform.

Embodiment 9 FIG.
FIG. 16 is a side sectional view schematically showing a main part of an induction heating cooker according to Embodiment 9 of the present invention. In the ninth embodiment, the heating coil 2 includes a first coil body 21 and a second coil body 22 that are divided into two via a gap D in the radial direction as in the fifth embodiment shown in FIG. Has been. The ferrite 49 is provided with a small cross-sectional area 49a having a recess 49b formed so as to cut the upper surface at a position corresponding to the first coil body 21. As shown in FIG. 9 of the fifth embodiment, when the heating coil 2 is divided into two, there is a peak position of the heat generation density at a position corresponding to the first coil body 21 disposed inside. The heating coil 2 needs to be cooled, and the peak position of the heat generation density is an area where the heat generation density of the cooking utensil 6 is desired to be lowered.

  However, in the ninth embodiment, the concave portion 49b is provided so that the concave portion 49b functions as a cooling air passage for the heating coil 2, and the small cross-sectional area portion 49a serves as a heat generation density of the cooking utensil 6. Can be lowered. On the other hand, in the innermost peripheral portion A and the outermost peripheral portion C of the first coil body 21 having a low heat generation density, the magnetic flux is concentrated by extending the ferrite 49, and the heat generation efficiency is improved. Needless to say, the cross-sectional area of the ferrite 49 along the radial direction may be changed due to unevenness according to the heat generation density, for example, as illustrated in FIG. According to the ninth embodiment configured as described above, the distribution along the radial direction of the heat generation efficiency or the temperature of the cooking utensil 6 can be made more constant, and the air path can be secured.

It is a figure which illustrates typically the principal part of the induction heating cooking appliance by Embodiment 1 of this invention, (a) is a rear view which shows the shape and arrangement | positioning with respect to a heating coil of a high-permeability member, (b) is high The top view which shows a magnetic permeability member. Side surface sectional drawing of Fig.1 (a). The principal part of the induction heating cooking appliance which concerns on Embodiment 2 of this invention is shown typically, (a) is a rear view which shows a high magnetic permeability member and a heating coil, (b) is side sectional drawing. Side surface sectional drawing which shows typically the principal part of the induction heating cooking appliance which concerns on Embodiment 3 of this invention. Side surface sectional drawing which shows typically the principal part of the induction heating cooking appliance which concerns on Embodiment 4 of this invention. It is side surface sectional drawing which shows the modification of FIG. The rear view which shows typically the principal part of the induction heating cooking appliance by Embodiment 5 of this invention. Side surface sectional drawing of FIG. The figure which shows the heat generation density in the cooking appliance bottom part by the structure shown in FIG. The rear view which shows the modification of FIG. The fragmentary sectional view which shows the principal part of the induction heating cooking appliance by Embodiment 6 of this invention. The rear view which shows typically the principal part of the induction heating cooking appliance by Embodiment 7 of this invention. FIG. 13 is a diagram corresponding to a cross-sectional view taken along line XIII-XIII in FIG. 12. The rear view which shows typically the principal part of the induction heating cooking appliance by Embodiment 8 of this invention. The figure equivalent to the arrow sectional view in the XV-XV line | wire of FIG. Side surface sectional drawing which shows typically the principal part of the induction heating cooking appliance by Embodiment 9 of this invention. The reference figure which shows the calculation result of the heat_generation | fever density of the cooking appliance bottom with respect to the radius of a cooking appliance, when the width | variety of a ferrite is made constant along a radial direction. FIG. 5 is a reference diagram for explaining an arrangement example of ferrite for increasing the heat generation efficiency at the center of the heating coil.

  DESCRIPTION OF SYMBOLS 1 induction heating cooker, 2 heating coil, 21 1st coil body, 22 2nd coil body, 3 drive circuit, 4, 41, 42, 43, 44, 45, 46, 47, 48, 49 ferrite (high Permeability member), 4a, 4b, 41a, 41b, 49a small cross section, 4c, 4d, 41c, 41d, 44a, 45b, 46a, 48b large cross section, 41e tip, 42a first high magnetic permeability Material, 42b second high permeability material, 43a first part, 43b, 43c second part, 47a, 48a ferrite body, 47b block-like high permeability member, 49b recess, 5 air path, 5a gap, 51 Gap, 6 Cooking utensil, 7 Temperature sensor, A Innermost circumference, B Middle, C Outermost circumference, D Gap, R Distance from the center of cooking utensil bottom , Θ the central axis.

Claims (2)

A circular shape for heating a cooking utensil comprising a first coil body provided at the center and a second coil body disposed around the outer periphery of the first coil body via a ring-shaped gap. In the induction heating cooker comprising a heating coil, a drive circuit for passing current to the heating coil, and a plurality of high permeability members arranged radially on one side of the heating coil, the high permeability member is The heating coil is disposed through a gap between the lower surface of the heating coil, and a recess is provided at an upper portion corresponding to a position directly below the first coil body, and a space formed by the recess is communicated with the gap to be cooled. An induction heating cooker characterized by having an air duct .   The induction heating cooker according to claim 1, wherein the concave portion is formed by scraping an upper surface of the high magnetic permeability member.

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