JPH05251170A - Induction heating cooker - Google Patents

Abstract

PURPOSE:To provide an induction heating cooker having the performance, which reduces the deformation due to the lowering of mechanical and thermal strength and the unevenness of heating temperature and the unevenness of temperature reset and which obtains the sufficient practical thermal power responsiveness and the sufficient practical thermal power strength to eliminate the practical trouble of the unevenness of temperature. CONSTITUTION:A square-shape rib 5 having a cross section projecting downward is provided in the bottom surface of a cooking plate 4 as a container, which is to be placed on an oven plate 1 and of which bottom surface is heated by heating coils 2 and 3, at a part corresponding to the periphery of the flat surface of the top surface of the cooking plate 4. This rib 5 is formed so as to surround a part positions of the heating coils 2, 3.

Description

Detailed Description of the Invention

[0001]

FIELD OF THE INVENTION The present invention relates to an induction heating cooker.

[0002]

2. Description of the Related Art In recent years, it has been considered that an induction heating cooker includes a container such as a special cooking pot or a cooking plate in order to bring out its characteristics. One of the features of the induction heating cooker is that it has a quicker thermal power response than the sheathed heater, which is one of the heat sources of conventional cooking utensils.To bring out this feature more, it is necessary to reduce the heat capacity of the container. It is effective, and reducing the wall thickness of the container is an effective means.

A conventional induction heating cooker is shown below in FIG.
The description will be made with reference to FIG.

In the figure, 21 is a top plate which also serves as an outer shell of the main body, 22 and 23 are first and second heating coils provided in the main body below the top plate 21, and 24 is a bottom plate placed on the top plate 21. The iron sprayed film is a cooking plate made of aluminum die cast which is a container heated by the heating coils 22 and 23, and 25 is a flat surface of the cooking plate which is a cooking surface when the cooking plate 24 is heated by the heating coils 22 and 23. It shows a temperature distribution curve. In addition, the thickness of the flat portion of the cooking plate 24 is 2 in order to bring out quick heat response which is one of the features of the induction heating cooker.
It was set to about mm.

[0005]

In the structure of the conventional induction heating cooker as described above, reducing the thickness of the cooking plate 24 not only lowers the mechanical strength in practical use, but also When it rises to a high temperature due to baking, it is deformed by rapid cooling such as sprinkling with water and its thermal strength is weak,
Further, one of the disadvantages of the induction heating cooker is that the heating surface temperature rise of the portions located on the heating coils 22 and 23 is high, but the heating surface temperature rise of the portions off the heating coils 22 and 23 is low. The unevenness appears more conspicuously, and the temperature of the temperature distribution curve 25 is greatly reduced at both end portions of the temperature distribution curve 25 that are off the heating coils 22 and 23 and the central portion between the heating coils. In addition, when the food is placed on the portions of the cooking plate 24 located on the heating coils 22 and 23, the temperature recovery is fast, but the food is placed on the portions of the cooking plate 24 off the heating coils 22 and 23. However, there was a problem that the temperature recovery even when the temperature was not sufficiently obtained and the temperature recovery unevenness appeared remarkably.

The present invention is to solve the above-mentioned problems, and it is a first object of the present invention to provide an induction heating cooker capable of reducing the degree of temperature decrease when a food is placed on the outer peripheral portion of the container where the temperature is likely to decrease. To aim.

A second object is to reduce the degree of temperature decrease of the container when the food is placed between the adjacent heating coils in the case of having a plurality of heating coils.

A third object is to delay the temperature rising rate of the upper portion of the heating coil of the container, which is the portion where the temperature easily rises, to make the heating temperature of the container uniform and at the same time improve the thermal and mechanical strength. To do.

A fourth object is to disperse the heat generated in the upper portion of the heating coil of the container where the temperature easily rises over the entire surface of the container to make uniform the heating temperature unevenness and the temperature recovery unevenness of the container, and at the same time, the thermal It is to improve the mechanical hardness.

[0010]

In order to achieve the above-mentioned first object, the first means of the induction heating cooker of the present invention is a top plate which also serves as an outer shell of a main body in which a heating coil is arranged in the lower main body. A container to be placed is provided, and the lower surface of the container has a convex shape at least in a portion substantially facing the outer periphery of the upper surface flat portion.

In order to achieve the second object, the second means is provided with a container which is placed on a top plate which also serves as an outer shell of the main body in which a plurality of heating coils are arranged in the lower main body, and the lower surface of the container is provided. Has a configuration in which a portion located between at least a plurality of adjacent heating coils has a convex shape.

In order to achieve the third object, the third means is provided with a container placed on a top plate which also serves as an outer shell of the main body in which a heating coil is arranged in the lower main body, and at least the lower surface of the container is heated. The configuration includes an annular convex portion above the coil and a second convex portion protruding outward or inward from the annular convex portion.

Further, in order to achieve the fourth object, the fourth
Means comprises a container placed on a top plate which also serves as an outer shell of the main body in which a heating coil is arranged in the lower main body, and a lower surface of the container has at least an upper portion of the heating coil with a substantially radial convex portion with respect to the center of the heating coil. Prepared for the configuration.

[0014]

According to the induction heating cooker of the present invention, by the constitution of the above-mentioned first means, the outer peripheral portion of the flat portion corresponding to the end portion of the cooking surface of the container is easily displaced from the heating coil and the magnetic force is hard to reach so that the cooked food is The amount of temperature decrease increases once placed and the temperature decreases once, but the heat storage amount is increased by increasing the wall thickness by making the bottom surface of the container convex so that the temperature decrease degree when the food is placed on the outer periphery of the container Can be reduced.

Further, according to the structure of the second means, when a plurality of heating coils are provided in the main body, at least the portion located between the adjacent heating coils is convex on the lower surface of the container, This part tends to be out of the heating coil and the magnetic force is hard to reach, so the food is placed and the temperature tends to decrease, but since the lower surface is convex, the heat storage amount is large and the adjacent heating It is possible to reduce the degree of temperature decrease when the food is placed between the coils.

According to the structure of the third means, at least the annular convex portion above the heating coil and the second convex portion protruding outward or inward from the annular convex portion are provided on the lower surface of the container. , The magnetic density generated by the heating coil is high and the temperature is easily increased by heating, so that the heat capacity of the upper part of the heating coil of the container can be increased, the temperature rising speed is delayed to make the heating temperature of the container uniform, and at the same time, the annular convex portion -It is reinforced by the second protrusion protruding inward, so that the thermal and mechanical strength can be improved.

Further, according to the constitution of the fourth means, since the lower surface of the container is provided with the convex portion substantially radial with respect to the center of the heating coil at least in the portion located above the heating coil, the magnetic density generated by the heating coil is high. The heat generated in the upper part of the heating coil of the container where the temperature tends to rise due to heating is dispersed inward and outward by the substantially radial convex parts, so that the heating surface of the container is equalized and food is placed. Even if a local temperature drop occurs, heat is supplemented from the surroundings by being transmitted through the convex portion, so that the temperature can be quickly recovered. In addition, the substantially radial projections cover almost the entire bottom surface of the cooking plate, so mechanical reinforcement is made, resulting in mechanical shock and high temperature rise.
The strength against thermal shock such as quenching can be improved.

[0018]

【Example】

(Embodiment 1) An embodiment of the present invention will be described below with reference to FIGS.

In the figure, reference numeral 1 denotes a top plate which also serves as an outer shell of the main body,
2 and 3 are first and second heating coils provided in the main body under the top plate 1, and 4 is a container placed on the top plate 1 and the iron sprayed film on the bottom surface is heated by the heating coils 2 and 3. It is an aluminum die-cast cooking plate. The bottom surface of the cooking plate 4 is provided with a substantially quadrilateral rib 5 having a downward convex cross-section at a portion substantially facing the outer periphery of the flat surface of the top surface. The rib 5 has two ribs indicating the position of the heating coil. It is provided so as to enclose a dotted-chain circle.

The operation of the induction heating cooker configured as described above is as follows. The outer peripheral portion of the flat surface of the cooking plate 4 is located outside the heating coils 2 and 3, and the magnetic force is hard to reach. To increase the amount of heat storage by providing a rib 5 having a convex lower surface at a portion substantially opposite to the outer circumference of the portion to increase the amount of heat storage, and to reduce the degree of temperature decrease when the food is placed on the outer circumference of the cooking plate. Will be possible.

(Second Embodiment) A second embodiment of the present invention will be described below with reference to FIGS. 3 and 4.

The same parts as those of the first embodiment are designated by the same reference numerals and detailed description thereof will be omitted. As shown in the figure, a rib 6 having a convex cross section is also provided in a portion located between the two heating coils 2 and 3, and the rib 5 and the rib 6 are connected and integrated. Then, the ribs 5 and 6 are arranged so as to surround two two-dot chain lines indicating the position of the heating coil.

The operation of the second embodiment will be described below. The bottom of the cooking plate 4 has two adjacent heating coils 2
Since the rib 6 is provided by making the portion located between and 3 into a convex shape, this portion is likely to be located away from the heating coils 2 and 3 and the magnetic force is hard to reach, and the temperature of the cooked food is apt to drop. However, since the wall thickness is large, the amount of heat storage is large, and it is possible to reduce the degree of temperature decrease when the food is placed between the adjacent heating coils 2 and 3. Further, in the second embodiment, since the rectangular rib 5 is also provided near the outer periphery of the flat surface of the cooking plate, the heat storage amount can be increased also in this portion, and the degree of temperature decrease when the food is placed can be reduced. It will be possible.

(Embodiment 3) A third embodiment of the present invention will be described below with reference to FIGS.

The same parts as those in the first embodiment are designated by the same reference numerals and detailed description thereof will be omitted. As shown in the figure, the bottom of the cooking plate 4 is provided with ribs 7 having a convex cross-section in the vertical and horizontal directions in a grid pattern, and the grid ribs 7 are formed in squares in the portions located above the heating coils 2 and 3, respectively. Annular ribs 8 and 9 (shown in phantom in FIG. 6) are configured. Therefore, the rib arrangement on the back surface of the cooking plate 4 is such that the rib 1 of the second convex portion protruding outward from the two rectangular annular ribs 8 and 9 is formed.
It is configured to cover the back surface of the cooking plate 4 with a series of 0s.

The operation of the second embodiment will be described below. On the lower surface of the cooking plate 4, ribs 8 and 9 which are annular convex portions above the heating coils 2 and 3 and a rib 10 which is a second convex portion protruding outward from the ribs 8 and 9 are provided.
Since the heating coils 2 and 3 are provided with a high magnetic density, the heat capacity of the upper portions of the heating coils 2 and 3 of the cooking plate 4 in which the temperature easily rises due to heating can be increased, and the temperature rising speed of this portion can be delayed. Cooking plate 4
At the same time as making the heating temperature uniform, the bottom surface of the cooking plate 4 is reinforced by the second protrusions 10 protruding outward from the ribs 8 and 9 that are annular protrusions, and the thermal and mechanical strength is improved. In a practical use, it can be a cooking plate that is not deformed by punching, emptying, quenching, etc.

(Fourth Embodiment) A fourth embodiment of the present invention will be described below with reference to FIGS. 7 and 8.

The same parts as those in the first embodiment are designated by the same reference numerals and detailed description thereof will be omitted. As shown in the drawing, on the lower surface of the cooking plate 4, at least the portions located above the heating coils 2 and 3 are provided with ribs 11 which are convex portions from the portion with respect to the center of the heating coils 2 and 3 in a substantially radial pattern. It is connected to a rectangular rib 12 provided in substantially the same shape as the outer periphery of the flat surface of the cooking plate.

The operation of the fourth embodiment will be described below. The heat generated in the upper portions of the heating coils 2 and 3 of the cooking plate 4 is dispersed inward and outward by a substantially radial rib 11 provided on the lower surface of the cooking plate 4 centering on a point with respect to the centers of the heating coils 2 and 3. Cooked plate 4
The heating surface is heated so that even if a temperature drop occurs locally such as when a cooked food is placed, the heat is transmitted through the ribs 11 to be supplemented from the surroundings, so that the temperature can be quickly recovered.
In addition, the substantially radial ribs 11 cover almost the entire bottom surface of the cooking plate 4, so that the ribs 11 are mechanically reinforced and can sufficiently withstand practical impacts such as mechanical shocks and thermal shocks such as high temperature rise and rapid cooling. The strength can be obtained.

[0030]

As is apparent from the above embodiments, according to the present invention, at least the portion of the lower surface of the container that substantially opposes the outer periphery of the upper surface is convex, so that the heat storage amount in the outer peripheral portion of the container is large. Therefore, it is possible to reduce the degree of temperature decrease when the food is placed on the outer peripheral portion of the container.

Further, in the case where the lower surface of the container has a convex portion located between at least a plurality of adjacent heating coils, the temperature is low when the food is placed because the heat generated is small because it is located off the heating coil. However, since the lower surface is convex, the amount of accumulated heat is large, and the degree of temperature decrease when the food is placed between the adjacent heating coils is reduced.

A container provided with at least an annular convex portion above the heating coil and a second convex portion protruding outward or inward from the annular convex portion on the lower surface of the container is a container whose temperature easily rises. The heat capacity of the upper part of the heating coil can be increased, the temperature rising rate can be delayed to make the heating temperature of the container uniform, and at the same time, the second protruding from the annular convex part to the outside and the inside
It is reinforced by the convex portions of and the thermal and mechanical strength can be improved.

Further, in the case where the lower surface of the container is provided with a convex portion substantially radial with respect to the center of the heating coil at least in a portion located above the heating coil, the heat generated in the upper portion of the heating coil of the container is substantially radial convex portion. Disperses inward and outward, so that the heating surface of the container is soaked, and even if the temperature drops locally due to the food being cooked, the heat is transmitted through the convex portion and the heat is supplemented from the surroundings, so that the temperature is recovered quickly. .. In addition, the substantially radial protrusions cover almost the entire bottom surface of the container, providing mechanical reinforcement and improving the strength against mechanical shock and thermal shock such as high temperature rise and rapid cooling. A heating cooker can be provided.

[Brief description of drawings]

FIG. 1 is a sectional view of an induction heating cooker according to a first embodiment of the present invention.

FIG. 2 is a bottom view of the cooking plate of the induction heating cooker according to the first embodiment.

FIG. 3 is a sectional view of the induction heating cooker according to the second embodiment.

FIG. 4 is a bottom view of the cooking plate of the induction heating cooker according to the second embodiment.

FIG. 5 is a sectional view of an induction heating cooker according to the third embodiment.

FIG. 6 is a bottom view of the cooking plate of the induction heating cooker according to the third embodiment.

FIG. 7 is a sectional view of an induction heating cooker according to the fourth embodiment.

FIG. 8 is a bottom view of the cooking plate of the induction heating cooker according to the fourth embodiment.

FIG. 9 is a sectional view of a conventional induction heating cooker.

FIG. 10 is a partial cross-sectional view for explaining the operation of the induction heating cooker.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Top plate 2,3 Heating coil 4 Cooking plate (container) 5 Square rib (convex part) 6 Rib (convex part) located between heating coils 8,9 Annular convex part 10 Second convex part 11 Radial rib ( Radial projection)

Claims (4)

[Claims] 1. A guide which is provided with a container placed on a top plate which also functions as an outer shell of a main body in which a heating coil is disposed in a lower main body, and the lower surface of the container has a convex shape at least in a portion substantially facing the outer periphery of the upper surface flat portion. Heating cooker. 2. A container mounted on a top plate which also serves as an outer shell of a main body, in which a plurality of heating coils are disposed in a lower main body, and the lower surface of the container is located at least between the plurality of adjacent heating coils. An induction heating cooker with a convex portion. 3. A container mounted on a top plate which also serves as an outer shell of a main body, wherein a heating coil is disposed in a lower main body, and an annular convex portion above the heating coil and at least an annular convex portion on the lower surface of the container. An induction heating cooker provided with a second convex portion protruding outwardly or inwardly. 4. A container mounted on a top plate which also serves as an outer shell of a main body, in which a heating coil is disposed in a lower main body, and the lower surface of the container is at least above the heating coil and substantially at the center of the heating coil. An induction heating cooker provided with radial protrusions.