JP3276309B2 - Electromagnetic induction heating cooking container - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an electromagnetic induction heating cooking container, which is installed in the vicinity of an induction heating coil, generates an induction current by a high frequency magnetic field generated from the induction heating coil, and performs cooking by the induction current. The present invention relates to a cooking container in which a container itself generates heat and cooks contents.

[0002]

2. Description of the Related Art Conventionally, as an electromagnetic induction heating cooking container that generates heat by an induction current when used together with an induction heating coil of this type, a container made of a magnetic material such as iron is generally used.

However, this type is heavy and difficult to handle because it is mainly composed of iron having a large specific gravity. for that reason,
By using a non-magnetic material such as aluminum as the main material and attaching a magnetic material as a cladding material to the outer surface,
Electromagnetic induction heating with magnetism is performed.

However, these materials also have problems in cost and corrosion resistance, and it is difficult to partially adjust the thickness of the magnetic material by the method of attaching a clad material. Have difficulty.

Japanese Patent Application Laid-Open No. 9-3576 discloses that a nickel-cobalt alloy is plated on the outer surface of a nonmagnetic material, and an induced current is generated in the plating layer to generate heat.

[0006]

However, in the invention described in the above publication, the thickness of the plating layer is 10 to 100.
Since the resistance to the induced current generated by the magnetic field lines penetrating the plating layer is large because it is as thin as micron, a sufficient induced current cannot be generated, the output power is reduced, and the resistance of the induced current is large. The coil generates heat, and the coil becomes unnecessarily hot. Further, these cooking containers are not completely uniform over the entire circumference of the container, and heat is easily transmitted to the outside through the handle at a place where the handle is attached, so that the temperature does not rise sufficiently. , Causing uneven heating.

SUMMARY OF THE INVENTION The present invention has been made in view of the above circumstances, and a thermal sprayed film layer of a magnetic material is formed on the outer surface of a non-magnetic material to enable induction heating, and a coil is required along with the induction heating. An object of the present invention is to provide an electromagnetic induction heating cooking container that does not generate heat as described above.

[0008]

According to the present invention, there is provided a method for forming a thermally sprayed film layer having a thickness of 400 to 600 microns made of a magnetic metal on an outer surface of a base made of a non-magnetic material of a cooking container, The thickness of the sprayed film layer is increased in the vicinity of the portion where the handle is attached in the circumferential direction of the cooking vessel, as compared with other portions.

In the present invention, the nonmagnetic material may be aluminum or copper. As the metal having magnetism, iron, cobalt, nickel, ruthenium, rhodium, palladium, osmium, iridium, platinum or an alloy thereof is suitable.

[0010]

[0011]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS FIG. 1 shows an electromagnetic induction heating rice cooker 1 using an electromagnetic induction heating cooking container of the present invention as an inner pot, in which an induction heating coil 3 is installed in an exterior body 2, An inner pot 4 is placed on the induction heating coil 3. Reference numeral 9 denotes a temperature sensor, and reference numeral 10 denotes a lid that covers an upper portion of the exterior body 2.

In the inner pan 4, reference numeral 5 denotes an inner pan substrate made of a non-magnetic material such as aluminum, and a sprayed film layer 6 made of a magnetic metal such as iron is formed on the outer surface from the bottom surface to the lower side surface. Is formed.

The inner pot base material 5 needs to be made of a non-magnetic material. Aluminum or copper is suitable as the material, but non-magnetic stainless steel such as SUS-304 can also be used. It is also possible to use a non-metallic material such as a ceramic material or glass.

The sprayed film layer 6 is a metal having magnetism, such as iron, cobalt, nickel, ruthenium, rhodium,
Transition metals such as palladium, osmium, iridium or platinum or alloys thereof are suitable.

In the present invention, it is necessary that the thickness of the sprayed film layer 6 is 400 microns or more. 40
If the diameter is less than 0 μm, the induction heating coil 3 generates heat, the temperature of the induction heating coil 3 becomes unnecessarily high, and a part of the input power is consumed by the coil 3 to cause a loss. When the thickness of the thermal spray coating layer 6 increases, the temperature of the induction heating coil 3 decreases. However, the temperature is limited to about 600 μm.

The average thickness of the sprayed film layer 6 must be 400 microns or more in a range where the sprayed film layer 6 of the inner pan 4 comes into contact with the magnetic flux generated from the induction heating coil 3. However, there is no problem even if the sprayed film layer 6 is formed beyond the range, and the thickness at that portion may be thin. Further, the sprayed film layer 6 may not be formed at the portion in contact with the temperature sensor 9.

Further, the thickness of the sprayed film layer 6 in a range where the magnetic flux is in contact with the magnetic flux can be partially changed.
The density of the magnetic flux generated from the induction heating coil 3 is not necessarily uniform, but varies partly in a large or small manner. However, it is preferable to change the thickness of the sprayed film layer 6 almost in proportion to the distribution of the magnetic flux.

In the present invention, the thickness of the sprayed film layer 6 is larger in the vicinity of the handle 7 attached to the inner pot 4 than in other portions. In the circumferential direction of the sprayed film layer 6, heat is easily transmitted to the outside in the vicinity of the handle 7 due to its structure, and it is easy to escape. By increasing the thickness of the sprayed film layer 6 in the vicinity of the portion, the amount of heat generated by electromagnetic induction is increased. Is increased, and the heat escaping from the handle 7 is compensated for.

FIGS. 2 and 3 show the inner pan 4 having the above-mentioned handle 7.
The thermal spray coating layer 6 is formed on the outer surface of the inner pot base material 5. Handles 7 are attached to the upper end of the inner pan 4 at two opposing positions, and the sprayed film layer 6 below the handle 7 is formed with a thickened portion 8. Although the thickness of the thickness increasing portion 8 depends on the structure of the inner pan 4 and the exterior body 2 in the portion of the handle 7, it is appropriate that the average thickness of the sprayed film layer 6 is larger by 20 to 100%.

Although the electromagnetic induction heating cooking container of the present invention can be used as the inner pot 4 of the electromagnetic induction heating rice cooker 1, a cooking container for storing contents in other cooking utensils having an electromagnetic induction heating function. Can be applied to
Further, the present invention can be applied to a cooking container usable in a general electromagnetic cooker, and can also be applied as a pot, a frying pan, a hot plate, and the like.

[0021]

According to the study by the inventors, as the thickness of the sprayed film layer 6 increases, the induction current is generated effectively and the cooking vessel generates heat, so that the output power as an electromagnetic cooking appliance increases. In addition, since the magnetic lines of force generated from the coil are effectively used for heat generation of the cooking container, unnecessary heat generation of the coil is suppressed.

In the electromagnetic induction heating rice cooker 1 shown in FIG. 1, an inner pot 4 in which a sprayed film layer 6 in which the thickness of a sprayed film is variously changed is formed on a 2.5 mm thick inner pot base material 5 made of aluminum. And put water in the inner pan 4 to input power 50
The power was supplied at 0 W for 1 hour, and the output power and the maximum temperature of the surface of the induction heating coil 3 were measured. The results were as shown in Table 1 below.

[0023]

[Table 1]

As can be understood from the numerical values in Table 1,
If the thickness of the sprayed film layer 6 is less than 400 microns, the output power is insufficient and the temperature of the induction heating coil 3 is high.
Unnecessarily generating heat. The output power hardly changes even if it exceeds 600 microns, and the temperature of the coil 3 hardly changes.

[0025]

Thus, according to the present invention, since the sprayed film layer 6 made of a magnetic material is formed on the base material 5 made of a non-magnetic material, it is lighter than a cooking vessel mainly made of iron. By using aluminum or copper having good thermal conductivity as the material 5, the heat transfer efficiency as a cooking container can be increased.

Further, the input power is efficiently converted to heat generated by electromagnetic induction heating, and a large output power equivalent to the case of using a conventional iron-based cooking vessel is obtained, so that the object to be cooked is efficiently cooked. And the induction heating coil does not generate unnecessary heat.

By changing the thickness of the sprayed film layer 6 almost in proportion to the distribution of the magnetic flux generated from the induction heating coil 3, the entire inner pan 4 is heated almost uniformly, and the partial heating is performed. Unevenness is less likely to occur.

Further, according to the present invention, the thickness of the sprayed film layer 6 is thicker in the vicinity of the handle 7 attached to the inner pan 4 than in the other parts, so that the part is more thick than the other parts. Also, more heat is generated by the electromagnetic induction, and the heat escaping from the handle 7 can be replenished, so that uneven heating does not occur.

[Brief description of the drawings]

FIG. 1 is a central longitudinal sectional view of an electromagnetic induction heating rice cooker to which the present invention is applied as an inner pot.

FIG. 2 is a central longitudinal sectional view of an inner pot having a handle of the rice cooker.

FIG. 3 is a cross-sectional view of the inner pan, taken along the line III-III. 3 Induction heating coil 4 Cooking vessel 5 Base material 6 Thermal spray film layer 7 Handle 8 Thickness increasing portion

──────────────────────────────────────────────────続 き Continuation of the front page (56) References JP-A-8-228911 (JP, A) JP-A-7-184768 (JP, A) JP-A 8-131337 (JP, A) JP-A-8-131 140832 (JP, A) Japanese Utility Model Application 3-58221 (JP, U) (58) Fields investigated (Int. Cl. ⁷ , DB name) A47J 27/00 103 A47J 27/00 104 A47J 36/02

Claims (3)

(57) [Claims] 1. A thickness 40 made of a magnetic metal is provided on an outer surface of a base (5) made of a non-magnetic material of a cooking vessel (4).
A spray coating layer (6) of 0 to 600 microns is formed, and the vicinity of the portion where the handle (7) is attached in the circumferential direction of the cooking vessel (4) is compared with the other portions. ), The electromagnetic induction heating cooking container characterized by thickening 2. The electromagnetic induction heating cooking container according to claim 1, wherein the non-magnetic material forming the substrate (5) is aluminum or copper. 3. The magnetic metal forming the thermal spray coating layer (6) is iron, cobalt, nickel, ruthenium, rhodium, palladium, osmium, iridium, platinum or an alloy thereof. The electromagnetic induction heating cooking container according to claim 1 or 2.