JPH04220988A - Deep pan for electromagnetic cooking apparatus - Google Patents

Abstract

PURPOSE:To provide a deep pan solely devoted to an electromagnetic induction heating cooking apparatus equipped with self temp. controlling function, by adopting the constitution according to the invention as described hereunder. CONSTITUTION:A deep pan 1 to be solely devoted to an electromagnetic cooking apparatus is configured with materials which are consolidated, wherein the inside is made of a non-magnetic metal material 1a such as Al while the outside is made of a magnetic metal material 1b having a specific Curie point. This deep pan 1 induced by a heater coil is heated to the Curie point - over the Curie point, the magnetic metal material 1b becomes non-magnetic metal material 1a and no heating takes place. That is, heating is put on and off around the Curie point. Accordingly the intended temp. control is made practicable with this deep pan itself 1.

Description

[Detailed description of the invention]

0001

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention particularly relates to a pot for an electromagnetic cooker having a self-temperature control function.

0002

[Prior technology] Electromagnetic induction cooking device (hereinafter referred to as an electromagnetic cooking device)
A heating coil is placed below the top plate, and the lines of magnetic force generated by the heating coil cause eddy currents in the bottom surface of the electromagnetic cooker pot on the top plate to generate heat.

[0003] Conventionally, pots for such electromagnetic cookers have been made of magnetic metal materials (iron, SUS430 stainless steel), magnetic metal materials (iron, SUS430 stainless steel, etc.) and non-magnetic metal materials (aluminum, SUS304 stainless steel, etc.). ) and cladding materials (two or multiple layers) are often used.

[0004] Such conventional pots are used with temperature control performed by a thermistor installed on the back side of the top plate.

[0005]

[Problems to be Solved by the Invention] However, in such conventional induction cookers, the thermal conductivity of the crystallized glass used in the top plate is low, so the actual temperature of the pot for the induction cooker and the thermistor are low. The temperature difference between the temperature and the sensitive temperature of the pot becomes large, the thermal response is poor, and it is difficult to control the temperature under abnormal usage conditions such as cooking, and pots made of metal have problems such as significant warping and deformation of the bottom surface. .

A first object of the present invention is to solve the above-mentioned conventional problems, and is to provide a pot for an electromagnetic cooker having a self-temperature control function.

A second object of the present invention is to solve the above-mentioned conventional problems and to provide a pot for an electromagnetic cooker that can be made lighter.

[0008]

[Means for Solving the Problem] In order to achieve the above object, the first means for solving the problem of the electromagnetic cooker pot (hereinafter referred to as an electromagnetic pot) of the present invention is to use a magnetic metal material having a predetermined Curie temperature and a non-magnetic metal material. It is composed of a magnetic metal material,
A second problem-solving means is constructed by integrating a magnetic metal material having a predetermined Curie temperature into at least a portion of the non-magnetic metal material facing the heating coil of the electromagnetic cooker.

[0009] Furthermore, the above-mentioned non-magnetic metal material is made of a good thermal conductor.

0010

[Operation] The present invention has the above-described structure, and in the electromagnetic cooker pot (electromagnetic pot) according to the first problem solving means, a non-magnetic metal material is placed on the inside that comes in contact with cooking, and a magnetic metal material having a Curie temperature is placed on the outside. When the temperature of the electromagnetic pot is below the Curie temperature, the alternating magnetic flux radiated from the heating coil flows into the outer magnetic metal material, but since its magnetic permeability is high, the alternating magnetic flux induces it. The eddy currents are concentrated on the bottom side of the electromagnetic pot due to the skin effect of the high-frequency current.

Therefore, most of the alternating magnetic flux flows through the outer magnetic metal material and is not affected by the inner non-magnetic metal material.

As a result, the eddy current flows intensively on the surface of the outer magnetic metal material (bottom side of the pot), the electric resistance of the electromagnetic pot becomes equivalently large, and the Joule heat generated by the eddy current increases. The amount of heat generated by induction heating increases.

On the other hand, above the Curie temperature, the magnetic metal material loses its magnetism, so its magnetic permeability decreases and the penetration depth of eddy currents (the depth from the surface until the surface current decreases to a constant rate) increases.

[0014] For this reason, eddy currents due to the alternating magnetic field also flow in the inner non-magnetic metal material, and as a whole, eddy currents flow in a large cross-sectional area of the entire bottom of the electromagnetic pot, so the equivalent electrical resistance becomes small. , the Joule heat generated is small and the amount of heat generated by induction heating is small.

[0015] To explain the changes in the heating operation step by step, when heating is started from room temperature, it heats with a large amount of heat until it reaches the Curie temperature, and as a result, the electromagnetic pot reaches the Curie temperature. Then, the electromagnetic pot itself automatically changes its characteristics and generates less heat.

[0016] Then, when the temperature of the electromagnetic pot decreases to below the Curie temperature, the outer magnetic metal material regains magnetism and resumes heating with a large amount of heat.

[0017] Here, if the Curie temperature of the outer magnetic metal material is selected to a desired set temperature, the electromagnetic pot itself can automatically control the amount of heat generated by the above-described operation.

[0018] Furthermore, if a material with lower electrical resistance (good thermal conductor) is selected as the inner non-magnetic metal material than the outer magnetic metal material, the difference in electrical resistance around the Curie temperature will become even larger, and the amount of heating will decrease. control width can be increased.

For these reasons, by setting the Curie temperature to the desired temperature, it becomes possible to control the temperature with high accuracy.

On the other hand, in the electromagnetic pot according to the second problem-solving means, a magnetic metal material having a predetermined Curie temperature is integrated into at least a portion of the non-magnetic metal material facing the heating coil of the electromagnetic cooker. A phenomenon similar to that of problem solving means 1 occurs, and by setting the Curie temperature to the desired temperature, it becomes possible to accurately control the temperature.

Furthermore, in the electromagnetic pot according to the second means for solving the problem, since the part that integrates the magnetic metal material is a part of the non-magnetic metal material, the weight of the electromagnetic pot is reduced, making it easy to use.

[0022] In the above, by using a good thermal conductor as the inner non-magnetic metal material, the uneven temperature distribution caused by the poor heat conduction of the magnetic metal material is eliminated, and the temperature of the food cooked inside the electromagnetic pot becomes uniform. As a result, cooking performance is significantly improved.

[0023] In addition, especially when used as an electromagnetic pot that uses water or oil, it is optimal for the Curie temperature of the magnetic metal material to be 300 degrees or less, and specific examples of magnetic metal materials include nickel alloys and iron-chromium alloys. Good.

Furthermore, as the non-magnetic metal material for the inner side in which the food is placed, aluminum, copper, etc., which are good thermal conductors, are preferable.

On the other hand, as an integration method in the second means for solving the problem, a cladding material may be used, adhesion using a brazing material or an inorganic adhesive, or pressure bonding using a hot press method. The part to be integrated may be at least the part facing the heating coil, and may be extended to a larger part, but weight reduction will be somewhat impaired.

[0026]

DESCRIPTION OF THE PREFERRED EMBODIMENTS Specific embodiments of the present invention will be described below with reference to the accompanying drawings.

(Embodiment 1) FIG. 1 shows a sectional view of a pot for an electromagnetic cooker according to Embodiment 1 of the present invention.

In the figure, reference numeral 1 denotes a pot for an electromagnetic cooker (electromagnetic pot); the inner side for storing food is made of a non-magnetic metal material 1a made of aluminum, which is a good thermal conductor, and the outer side is heated at 180 degrees. It is integrally made of a magnetic metal material 1b made of a nickel alloy having a Curie temperature of .

This electromagnetic pot 1 was formed by drawing using a clad material made of the two types of metal materials mentioned above.

In order to evaluate this electromagnetic pot 1, oil was poured into the electromagnetic pot 1, which was placed on the top plate of a conventional electromagnetic cooker, and tempura was cooked.

At this time, temperature control was performed by automatically turning on and off the temperature of the electromagnetic pot 1 when it reached 180 degrees, and the temperature of the oil was controlled at 180 degrees.

[0032] Also, even if the temperature of each part of the oil is measured, it is 180%
The temperature was extremely uniform. As a result, I was able to successfully cook tempura.

(Embodiment 2) FIG. 2 shows a sectional view of an electromagnetic pot according to Embodiment 2 of the present invention.

Namely, reference numeral 2 denotes an electromagnetic pot, and the inner side for storing food is made of a non-magnetic metal material 2a made of aluminum and a good thermal conductor, similar to that of the first embodiment.

Further, on the outside of the bottom surface of the non-magnetic metal material 2a facing the heating coil of the electromagnetic cooker, a magnetic metal material 2b made of a nickel alloy having a Curie temperature of 180 degrees is hot-pressed at a high temperature condition higher than the Curie temperature. They are integrated by pressure welding according to the law.

When this electromagnetic pot 2 was evaluated in the same manner as in Example 1, similar effects were obtained. Also, compared to the pot of Example 1, it was much lighter and easier to use.

Furthermore, tempura was cooked in the same manner as in Examples 1 and 2 using SUS304 stainless steel as the non-magnetic metal material, but the temperature was better in the electromagnetic pot 2 using the above-mentioned aluminum good thermal conductor. The temperature control is accurate, allowing you to cook tempura well, and it is also light in weight.
It has become even more user-friendly.

As is clear from the above two examples, the electromagnetic cooking pot of the present invention has a self-temperature control function, and has significant effects such as improving cooking performance and increasing safety against oil ignition. It was done.

In the embodiment of the present invention, aluminum or S
Although US304 stainless steel is used, the material is not particularly limited to this, and metal materials such as copper may also be used.

Further, although a nickel alloy is used as a magnetic metal material having a Curie temperature, the present invention is not limited to this.

Furthermore, although 180 degrees has been described as the Curie temperature, this is not particularly limited to this temperature either.

[0042]

As is clear from the above description, the pot for an electromagnetic cooker of the present invention is made of a magnetic metal material having a predetermined Curie temperature and a non-magnetic metal material. By integrating a magnetic metal material having a predetermined Curie temperature into a part of the non-magnetic metal material facing the heating coil, it is possible to provide a pot for an electromagnetic cooker each having a self-temperature control function.

[0043] By making the non-magnetic metal material a good thermal conductor, the temperature distribution of the pot for the electromagnetic cooker is improved, the cooking performance is significantly improved, and the weight can be further reduced, making it easier to use.

At the same time, the electromagnetic induction heating cooker not only eliminates the need for the conventional thermistor on the bottom of the top plate, but also eliminates the risk of fire or other dangers even if an abnormality occurs, such as the electromagnetic cooking pot not cooking properly. .

[Brief explanation of the drawing]

FIG. 1 (a) A cross-sectional view of a pot for an electromagnetic cooker according to Example 1 of the present invention. (b) An enlarged cross-sectional view of part A in (a).

FIG. 2 (a) Cross-sectional view of the electromagnetic cooker pot of Example 2 (
b) Enlarged sectional view of part A in (a)

[Explanation of symbols]

1, 2 Pots for electromagnetic cooker 1a, 2a
Non-magnetic metal material 1b, 2b Magnetic metal material

Claims (3)

[Claims] 1. A pot for an electromagnetic cooker comprising a magnetic metal material and a non-magnetic metal material having a predetermined Curie temperature. 2. A pot for an electromagnetic cooker, in which a magnetic metal material having a predetermined Curie temperature is integrated into at least a portion of the non-magnetic metal material facing the heating coil of the electromagnetic induction cooker. 3. The pot for an electromagnetic cooker according to claim 1 or 2, wherein the non-magnetic metal material is a good thermal conductor.