JPH10229940A - Electromagnetic induction heating type rice cooker - Google Patents

Abstract

PROBLEM TO BE SOLVED: To make it possible to achieve an enhanced efficiency both in heating at cooking rice and in thermal insulation at warm-keeping rice. SOLUTION: A flange 9 is fitted to the cook-pot setting part 8, where the cook-pot 4 is hung thereinto. Under a state of accommodating the cook-pot 4 into the inner frame 5, the entire surface of the heat insulation layer 15 is made so as to be not in contact with the inner frame 5. The heat reaching the heat insulation layer 15 is shut off at this non-contact part. The heat of the cook-pot 4 itself is, therefore, not transferred to the inner frame 5 side to enhance the thermal insulation capability of the cook-pot 4. The cook-pot 4 temperature can be restrained during stopping the heating of cook-pot 4. This can enhance the heating efficiency of the cook-pot 4.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an IH heating type rice cooker utilizing electromagnetic induction heating (hereinafter referred to as "IH heating"), which improves the heating efficiency during rice cooking and the heat retention efficiency during heat retention.

[0002]

Heretofore, in this type of jar combined rice cooker utilizing IH heating, a pot is selected from a magnetic metal material excellent in electromagnetic induction heating efficiency. In order to improve the thermal conductivity to the side of the pot, a material having good thermal conductivity such as aluminum is provided inside the magnetic metal material. The pot is formed by pressing using a clad material in which aluminum and stainless steel, which is a magnetic metal, are joined, or a stainless steel plate is joined when solidifying aluminum melt in a mold of a predetermined shape. There are various kinds. But in each case,
In the IH heating type rice cooker for jars, there is a problem that the pot has poor heat retention. The reason is that the pot itself generates heat by the magnetic metal material, and when the pot is heated indirectly from the outside of the pot using an electric heater, heat stays in the heating space outside the pot. , But the heat retention becomes higher, but this effect does not exist in the IH heating system where the pan itself generates heat.
Therefore, the heat retention becomes poor.

[0003] In addition, the poor heat retention of the pot causes a problem not only when keeping rice at a predetermined temperature but also when cooking rice. In other words, the rice cooking process that promotes water absorption of rice, the boiling continuous heating process that suppresses the amount of heating after boiling and keeps boiling moderately, and the unevenness that keeps the cooked rice from burning and keeping high temperature In the process or the like, the heating of the pot is performed intermittently, so that when the heating is not performed, the pot tends to cool down, which has been a factor of lowering the heating efficiency at the time of cooking rice.

[0004] In view of the above problems, it is an object of the present invention to provide an electromagnetic induction heating type rice cooker in which the heating efficiency during rice cooking and the heat retention efficiency during heat retention are improved.

[0005]

According to a first aspect of the present invention, there is provided an electromagnetic induction heating type rice cooker for achieving the above object.
It has a bottomed cylindrical pot and a pot storage unit that stores this pan,
The pot is mainly formed of a metal member, while a heat insulating layer is formed on the outside of the pot, an outwardly protruding flange is formed on an upper portion of the pot, and the upper portion is provided on an upper portion of the pot receiving portion. When the flange portion is placed on the pan placing portion and the pan is accommodated,
A gap is formed between the entire heat insulating layer of the pan and the pan accommodating portion.

According to the first aspect of the present invention, when the pot is stored, the entire surface of the heat insulating layer and the pan housing portion are in a non-contact state, and the heat reaching the heat insulating layer is blocked by the non-contact portion. As a result, the heat of the pot itself is not transmitted to the pot storage portion side, and as a result, it is possible to enhance the heat insulation of the pot and to prevent the temperature of the pot from dropping during cooking.

According to a second aspect of the present invention, there is provided an electromagnetic induction heating type rice cooker, wherein the heat insulating layer is made of a resin material such as a fluororesin or a silicone resin, glass or alumina. Characterized by being mixed with a fine-grained inorganic material.

According to the second aspect of the present invention, even if the heat insulating layer is formed on the outside of the pot, the inorganic material having excellent heat insulating properties is in the form of fine particles, so that the pot itself is not excessively enlarged.
The insulation of the pot can be improved. In addition, it is only necessary to paint and dry the resin material mixed with the heat insulating member on the outside of the pot, which has a great effect on manufacturing.

According to a third aspect of the present invention, in addition to the constitution of the second aspect, the electromagnetic induction heating type rice cooker further comprises an outer surface of the pot formed as a rough surface having an uneven shape by the heat insulating layer. .

[0010] According to the structure of the third aspect, particularly at the time of manufacturing, if the outer surface of the pot is checked, it can be easily determined whether or not the heat insulating layer has been applied. Even if the height of the convex portion on the outer surface of the pot varies, the entire surface of the heat-insulating layer and the pot housing are in a non-contact state, so that the heat of the pot escapes to the pot housing, There is no deterioration in the housing capacity.

According to a fourth aspect of the present invention, there is provided an electromagnetic induction heating type rice cooker according to the second aspect, wherein a pan temperature detecting means for detecting the temperature of the pan is brought into contact with an outer surface of the pan. The heat insulating layer is not formed on an outer surface of the pot at a contact portion of the pot temperature detecting means.

According to the structure of the fourth aspect, since the heat insulating layer is not formed at the portion of the pot temperature detecting means that contacts the outer surface of the pot, the temperature of the pot can be detected with high accuracy.

According to a fifth aspect of the present invention, there is provided an electromagnetic induction heating rice cooker according to the second aspect, wherein a pot temperature detecting means for detecting the temperature of the pot is brought into contact with the outer surface of the pot. The heat insulating layer on the outer surface of the pot at the contact portion of the pot temperature detecting means is formed thinner than other portions.

According to the structure of the fifth aspect, the portion of the pot temperature detecting means that contacts the outer surface of the pot has a heat insulating layer formed to be thinner than other portions, so that the temperature of the pot can be accurately detected. be able to. In addition, when forming the heat insulating layer, masking processing which is troublesome in manufacturing is not required.

Furthermore, in the electromagnetic induction heating type rice cooker according to claim 6 of the present invention, in addition to the configuration of claim 1, the pan is detachably accommodated from an upper opening of the pan accommodating section, and The same heat insulating layer as the outside of the pot is formed below the flange.

According to the configuration of claim 6, the lower side of the flange portion does not become so hot when holding the pan during the heat retention, and the usability when the pan is taken out from the pan storage portion is improved. Also,
Since the heat insulating layer can be formed on the lower side of the flange at the same time as the outside of the pot, a special manufacturing process is not required when forming the heat insulating layer on the flange. In addition, since there are no steps or grooves from the lower side of the flange portion to the outside of the pot, dirt does not enter and the appearance does not deteriorate. In addition, the temperature of the heat-insulating layer is lower than that of the metal surface constituting the pot, which makes it practically easier to use.

[0017]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the present invention will be described below with reference to the accompanying drawings.
In addition, the IH heating type rice cooker in this embodiment is an IH heating type jar rice cooker having a heat retaining function.

FIG. 1 is a sectional view of the IH-cooked rice cooker.
In the figure, 1 is a container body, 2 is an outer frame forming an outer shell of the container body 1, and a bottom plate 3 is fitted and fixed to an open lower end of the outer frame 2. In addition, inside the outer frame 2, there is a pan 4
Is provided with a bottomed cylindrical inner frame 5 serving as a pan storage section for detachably storing. The inner frame 5 includes an inner frame upper portion 6 integrally formed with the outer frame 2 made of polypropylene, and an outer frame 2 made of polyethylene terephthalate resin reinforced with glass fiber or polyamide resin reinforced with glass fiber. Is constructed by joining the inner frame lower part 7 of another part,
The upper part of the inner frame 5 is provided with a plurality of pot placing parts 8 partially projecting upward by about 1 to 3 mm. The pan mounting portion 8 is formed of a polyamide resin or a polyethylene terephthalate resin having excellent heat resistance, and the flange portion 9 formed on the upper outer peripheral portion of the pan 4 is mounted on the upper surface of the pan mounting portion 8. By placing, the pot 4 is housed inside the inner frame 5. In addition, if the pot placing portion 8 is formed of silicone rubber, the frictional resistance between the pot placing portion 8 and the outer surface of the pot 4 that contacts the pot placing portion 8 increases, so that the pot 4 becomes difficult to rotate during use, and the usability is improved. It is effective.

Here, the configuration of the bottomed cylindrical pot 4 for accommodating cooked materials such as rice, water and rice will be described with reference to FIGS.
This will be described in detail with reference to FIG. The pan 4 has a heat generating layer 12 made of a magnetic metal material such as ferrite stainless steel on the bottom and lower side of the main pot body 11 which is a main body of the pan 4 formed of a metal member having good thermal conductivity such as aluminum. Are joined. Further, a flange portion 9 protruding outward as described above is formed integrally with the pot 4 on the upper portion of the pot 4. On the outer surface of the pan 4, a paint 13 mainly composed of fluorine resin, silicone resin or polyethersulfone resin having a thickness of about 40 to 200 μm, alumina powder, titania powder, aluminum powder powder, glass powder powder, hollow glass A heat-insulating layer 15 is formed by painting a heat-insulating member mixed with a heat-insulating body 14 made of a fine-grained inorganic material having poor heat conductivity, selected from beads, glass fibers, mica powder, and the like (see FIG. 2). . Also, on the outer surface of the heat insulating layer 15,
Further, a paint mainly composed of a fluorine resin, a silicone resin or a polyether sulfone resin is applied and formed as a top coating layer 16 having a thickness of 10 to 50 μm (see FIG. 3). Insulation layer
The outer surface 15A of 15 is formed as an uneven rough surface in which the irregularities of the granular heat insulating main body 14 are left as they are. With this,
The outer surface 16A of the upper surface coating layer 16 which is the outer surface of the pan 4 is
Is formed on the rough surface along the outer surface 15A. These uneven outer surfaces 15A and 16A are clearly visible (0.05%).
mm).

The top coating layer 16 is not always necessary if it is colored by coating the heat insulating layer 15 and the appearance of the pot 4 can be properly treated. FIGS. 2 and 3 show an example of the heat insulating body 14 made of a granular inorganic material (inorganic powder). However, if glass having a high heat storage property is selected as the material of the heat insulating body 14, an excellent heat retaining effect can be obtained. Is obtained. In this case, as shown in FIG. 4, particularly when hollow glass beads are selected as the heat insulating body 14, the heat insulating effect of the pot 4 becomes more remarkable due to the internal air layer 17. In addition, the particle size of the heat insulating main body 14 is increased by the hollow portion, and the outer surface 15A of the heat insulating layer 15 is formed.
Can be clearly formed, and since no member is interposed in the hollow portion, it is possible to achieve a reduction in the weight of the pan 4 while improving the heat insulating effect. In addition,
At least on the inner surface of the portion of the pot main body 11 where the food contacts, for example, SUS3 selected from a material harder than the pot main body 11
Pot inner layer made of austenitic stainless steel such as 04
18 are joined.

Below the flange 9 formed on the upper outer surface of the pot 4, the same heat insulating layer 15 as the heat insulating layer 15 provided on the outer surface of the pot 4 is formed. The formation of the heat insulating layer 15 may be performed at the same time as the side surface of the pot 4 is painted for forming the heat insulating layer. That is, by turning the pan 4 upside down and painting from the bottom outer surface side of the pan 4, the outer surface of the pan 4 and the lower side of the flange portion 9 can be simultaneously and easily painted.

In FIG. 1, when the pot 4 is accommodated in the inner frame 5, the entire surface of the heat insulating layer 15 formed in the pot 4 is configured to be in non-contact with the inner surface of the inner frame 5. On the bottom and side surfaces of the pan 4, between the pan 4 and the inner frame 5 is 0.5 to 6 mm.
A gap 21 of about mm is formed. The smaller the gap 21 is, the more preferable the heat transfer of the pan 4 is suppressed. Also,
At the center of the bottom of the lower portion 6 of the inner frame, a pot temperature sensor 22 serving as a pan temperature detecting means is provided.
The temperature of the pot 4 is detected by contacting the bottom surface of the pan 4. In the present embodiment, the heat insulating layer 15 is formed in a portion other than the contact portion of the pot temperature sensor 22, and the heat insulating layer 15 is not formed on the outer surface of the pot 4 located in the contact portion. This is a pot mainly composed of the pan 4 by the heat insulation layer 15.
This is to prevent the temperature detection accuracy of 11 from deteriorating.
When the heat insulating layer 15 is coated on the outer surface of the pot 4, by masking the contact portion, the heat insulating layer 15 can be partially not formed. However, the masking process is troublesome, and the productivity is high. Cause aggravating factors. Therefore,
In this case, it is preferable to make the thickness of the heat insulating layer 15 at the contact portion smaller than at other portions. That is, when the heat insulating layer 15 is applied to the pot main body 11, the paint outlet is positioned over the side of the outer surface of the pot 11, and the paint 13 is placed on the bottom of the outer surface of the pot 4.
So that it does not Thereby, the heat insulation layer 15 is hardly formed at the bottom of the outer surface of the pan 4 or
Only the very thin heat-insulating layer 15 is formed, and the heat-insulating layer 15 can be formed only on a desired portion without deteriorating the manufacturability, and the temperature of the pan 4 can be accurately detected.

On the outer surface of the inner frame 5 corresponding to the heat generating layer 12 on the outer surface of the pan 4, an electromagnetic induction heating source formed by spirally winding a twisted litz wire formed by gathering copper wires insulated with polyurethane or the like. In addition, a heating coil 23 as a heating means is provided. The heating coil 23 is insert-molded when forming a coil base 24 made of a material such as polyethylene terephthalate reinforced with glass fiber, and has a configuration integrated with the coil base 24.
Is simply attached to the lower surface of the inner frame 5 by simply screwing it to the lower surface of the inner frame 5. Further, a power supply board 25 forming a power supply circuit and a heating control board 26 forming a control circuit of the heating coil 23 are disposed below the coil base 24 in the outer frame 2. The heating control board 26 includes an inverter circuit and supplies a high-frequency current of 24 to 30 kHz to the heating coil 23. When the high-frequency current is supplied, a magnetic field is generated in the heating coil 23 so that the heating layer 12 of the pan 4 is heated by IH heating to heat the pan 4.

On the heating control board 26, a switching element 27 as a heat generating component such as an IGBT element is provided with a radiator 28 mounted thereon. The heating control board 26 has a board temperature sensor.
29 are provided. On the upper side of the outer frame 2, an operation board
An operation panel 31 holding 30 is provided, and here, a plurality of operation switches 32 as operation means to be described later, and a display device 33 such as an LCD or an LED as display means are provided.

Reference numeral 41 denotes a lid body for opening and closing the upper surface opening of the pot 4, which is an outer lid 42, a frame-shaped outer lid cover 43 fixed to a lower peripheral portion of the outer lid 42, An outer shell is formed by the inner lid 44 that covers the opening inside the cover 43. This inner lid
The peripheral portion 44 is inserted between a lid reinforcing plate 45 located above the lid cover 43 and fixed on the outer lid cover 43 and an inner lid holding portion 46 formed to protrude on the inner peripheral surface of the outer lid cover 43. And is vertically movable with respect to the outer cover 43 in a predetermined range.
At the same time, the inner lid 44 is pressed downward by a spring 47 mounted between the inner lid 44 and the lid reinforcing plate 45. This is for improving the adhesion of the inner lid 44 to the pot 4. In addition, a lid packing 48 made of an annular elastic body is interposed between the peripheral part of the lid reinforcing plate 45 and the peripheral part of the inner lid 44.

A lid heater 51 and a lid temperature sensor 52 are provided on the upper surface, that is, the rear surface, of the inner lid 44. In addition, the outer lid
A steam port 53 and a steam port packing 54 made of an annular elastic body are attached to a central portion of 42. And steam port 53
The outer port cover 55 is engaged with a receiving portion 56 formed on the inner peripheral portion of the
Fixed to 42. On the other hand, a steam hole 57 is formed in the center of the inner lid 34 to communicate the inside of the pot 4 with the steam port 53 to the outside of the main body 1. In addition, the steam port packing 54
Is in close contact with the upper surface of the inner lid 44 around the vapor hole 57 to maintain airtightness. Reference numeral 58 denotes a hole for collecting the torn stored in the steam port 53 to the pot 4 side.

FIG. 5 schematically shows the configuration of the electrical control in the present embodiment. The microcomputer 61
Signals from the operation switch 32 provided on the operation panel 31 and the respective temperature sensors 22, 29, 52 are input, and based on the signals, via the IH drive circuit 62 and the high-frequency current generating means 63 on the heating control board 26, The output of the heating coil 23 and the power cutoff are controlled, the power cutoff of the lid heater 51 is controlled via the heater drive circuit 64 and the power cutoff means 65, and the operation panel 31 is controlled via the display drive circuit 66. The display operation of the provided display device 33 is controlled.

Next, the heating control at the time of cooking rice and at the time of keeping warm will be described with reference to the graph of FIG. In addition,
The solid line graph at the top of the figure shows the temperature of the pan temperature sensor 22, and the dotted line graph at the top of the figure shows the lid temperature sensor 52.
Shows the temperature. Also, the middle graph in the figure shows the timing and output of energization of the heating coil 23,
The lower graph in the same figure shows the energization timing and output of the lid heater 51. In the middle and lower graphs in the figure, the hatched portions indicate the energization timing. In the rice cooking step, each of the steps of boiled-cooking, boiling heating, boiling continuous heating, cooking, and steaming is sequentially performed. Hereinafter, the control of these steps will be described, but the numerical values and time specifically exemplified vary according to the rice cooking course, the product, and the like.

In the hot-boiled cooking, the output of the induction heating of the pan 4 is relatively low, and the water temperature in the pan 4 is heated to a high temperature of 60 ° C. or less to promote the water absorption of rice. After that, the process moves to the next boiling heating. It should be noted that it is not always necessary to perform the cooking, and it may be omitted. Boiling heating
This is the process of boiling the water in the pan 4. The heating coil 23
The output of IH heating by 1300W, 1000W, 700W, 4
It is divided into four stages of 00W, but 700W for one-sided cooking
, The boiling heating is the maximum heating amount of the heating coil 23
The pot 4 is heated by continuous energization of 1300W. Then, when the temperature of the lid temperature sensor 52 becomes 90 ° C. or higher during the boiling heating and the temperature change stabilizes at a predetermined temperature gradient, the process shifts to the boiling continuous heating. In this continuous boiling heating, the output of the IH heating to the pan 4 is slightly reduced,
By performing the predetermined intermittent energization, the heating amount is such that the boiling state of the water in the pan 4 continues for about 1 to 7 minutes. Then, when a predetermined stroke time elapses or when the temperature of the pot temperature sensor 22 rises by 2 to 5 ° C., the boiling continuous heating is finished, and the process shifts to cooking. In this cooking, the output of the IH heating to the pan 4 is set to the maximum of 1300 W and the intermittent energization is performed. Then, when the temperature of the pan temperature sensor 22 rises by 10 to 15 ° C., the cooking is finished and the process shifts to spots. In this spot, the output of IH heating to pan 4 was relatively low (700 W).
Then, heating is performed in accordance with the temperature of the pan temperature sensor 22, and the inside of the pan 4 is maintained at a high temperature so as not to cause scorching, thereby ensuring a spotting effect. Then, after a lapse of a predetermined period of time, the whirling is completed, and the process shifts to a warming process. In this warming process, the output of IH heating to the pan 4 is reduced to 400 W, and the pan 4 is heated by intermittent heating. For example, the basic configuration is an energization cycle in which the heating coil 23 is turned on for one second and turned off for seven seconds.
When the temperature of the pan 4 is lower than 70 ° C. at the time when the seven seconds off has elapsed, the configuration is such that energization for one second is performed, and the temperature of the rice in the pan 4 is maintained at about 70 to 76 ° C. In addition, in addition to 70-76 ° C, it is possible to use two types of heat, 64-70 ° C, and add a function to temporarily reheat the temperature of rice in the pan 4 to 80 ° C. Is also good. In any case, the heating means for heating the pot 4, that is, the heating coil 23, is configured to share the same IH heating as that for cooking rice. During cooking and warming, the inner lid 44 is heated by the lid heater 51 so that when the lid 41 is opened immediately after cooking or during the warming, dew condensation on the lower surface of the inner lid 44 does not flow down. I do.

As described above, in the present embodiment, in the IH heating type rice cooker in which the pan 4 itself is heated by the heat generating layer 12 made of a magnetic metal material, the pan 4 having a bottom and the pan 4 are accommodated. The pot 4 includes an inner frame 5 serving as a pot storage portion. The pot 4 forms a pot main body 11 mainly made of a metal member, while a heat insulating layer 15 is formed on the outside of the pot 4 and an outer layer is formed on an upper portion of the pot 4. The inner frame 5 is provided with a pot placing portion 8 on the upper portion, the flange portion 9 is placed on the pot placing portion 8 to accommodate the pan 4, and the inner frame 5 is formed on the inner frame 5. A gap 21 is formed between the entire surface of the heat insulating layer 15 of the pan 4 and the inner frame 5 in a state where the pan 4 is stored.
In other words, when the pot 4 is stored, the entire surface of the heat insulating layer 15 and the inner frame 5 are in a non-contact state, and the heat that reaches the heat insulating layer 15 is cut off by the non-contact portion. Is not transmitted to the inner frame 5 side (does not escape), and as a result, the heat retention of the pot 4 can be improved. In addition, at the time of cooking rice, a decrease in the temperature of the pan 4 during the period in which the heating of the pan 4 is stopped can be suppressed, so that the heating efficiency of the pan 4 can be increased and rice can be cooked without uneven heating, and uneven cooking can be achieved. It is possible to cook rice with less amount. Furthermore, when keeping warm, the pot 4 is hard to cool down, and power consumption during keeping warm is suppressed,
The disadvantage in the IH-cooked rice cooker can be improved.

In the present embodiment, the pot 4 is configured to be removably housed through the upper opening of the inner frame 5. In this case, since the outer surface temperature of the pan 4 is lowered by the heat insulating layer 15, it is safe to accidentally touch the outer surface of the pan 4 with a hand or the like when the pan 4 is taken out during the heat insulation. Moreover, when the heat insulating layer 15 is formed outside the pan 4, it is difficult to finish the thickness of the heat insulating layer 15 uniformly in manufacturing, and the outer surface dimensions of the pan 4 (the size of the pan 4) become uneven. However, in the present embodiment, when the pan 4 is accommodated in the inner frame 5, the outer diameter of the pan 4 including the heat insulating layer 15 is formed to be smaller than the minimum inner diameter of the inner frame 5 at the upper portion thereof. Even when the outside surface of the pan 4 is partially enlarged, when the pan 4 is detached from the inner frame 5, the pan 4 and the inner frame 5 do not come into contact with each other. Therefore, the accommodating property of the pan 4 in the inner frame 5 does not deteriorate, and problems such as the pan 4 being rubbed against the inner frame 5 and being difficult to enter into the inner frame 5 can be avoided. Further, in such a configuration, if the top coating layer 16 having good slipperiness is formed outside the heat insulating layer 15 as in the present embodiment, even if the pot 4 comes into contact with the inner frame 5, The inner surface is less likely to be scratched.

Further, in this embodiment, a heat insulating layer 15 is formed by mixing a heat insulating body 14 which is a fine granular inorganic material such as glass or alumina into a paint 13 which is a resin material such as a fluorine resin or a silicone resin. ing. Therefore, in this case, even if the heat insulating layer 15 is formed on the outside of the pot 4, the heat insulating main body 14 of the above-described material having excellent heat insulating properties is finely granular. By improving the heat insulating property of No. 4, it is possible to improve the above-described heating efficiency during rice cooking and the heat retention efficiency during heat retention. further,
It is only necessary to apply the resin material mixed with the heat insulating member to the outside of the pan 4 and dry it, and the productivity of the pan 4 can be remarkably improved.

In the present embodiment, the outer surface of the pot 4 is provided with a heat insulating layer.
Since the uneven surface is formed at 15, the outer surface of the pot 4 can be easily checked whether or not the heat insulating layer 15 has been applied, especially at the time of manufacturing. Further, even if the height of the convex portion on the outer surface of the pot 4 varies, the heat of the pot 4 escapes to the inner frame 5 because the entire surface of the heat insulating layer 15 and the inner frame 5 are in a non-contact state. There is no deterioration of the potability in the pot 4. Therefore, in this case, the presence or absence of the heat insulating layer 15 can be easily confirmed at the time of manufacturing, and the heat retaining property of the pot 4 and the accommodation property of the pot 4 in the inner frame 5 can be maintained well.

Further, in this embodiment, a pot temperature sensor 22 serving as a pot temperature detecting means for detecting the temperature of the pot 4 is provided in contact with the outer surface of the pot 4, and the pot temperature sensor 22 is provided on the outer surface of the pot 4 at the contact portion. The located heat insulating layer 15 is formed thinner than other portions or is not formed. With this configuration, the temperature of the pan 4 can be detected with high accuracy, so that the temperature of the pan 4 can be accurately controlled at the time of cooking rice and keeping the temperature warm. Is prevented from adversely affecting the temperature control at the time of cooking rice or keeping warm. Also, especially the former insulation layer
In the configuration in which the thickness of the heat insulating layer 15 is reduced, a troublesome masking process is not required, and the manufacturing effect when the heat insulating layer 15 is formed is large.

By the way, in this type of conventional electromagnetic induction heating type rice cooker, the temperature of the pot during the heat retention is usually about 60 to 75 ° C. However, since the material of the pot is made of metal, the upper part of the pot is When a hand (finger) touches the flange portion having the pot formed in the above, there was a dissatisfaction in use that the pot was hot and difficult to take out. Therefore, conventionally, a coating is applied to the lower side of the flange portion, but the thickness of the coating layer is as thin as 10 to 40 μm, and a sufficient effect cannot be obtained. There is also a plastic handle attached to the pan, but it has grooves and steps in the mounting part, and it has the drawback that it is difficult to clean when dirt enters, and the appearance of the pan deteriorates, There has also been a problem that the vessel body becomes large.

On the other hand, in the present embodiment, the pot 4 is removably accommodated in the upper opening of the inner frame 5.
Since the same heat insulating layer 15 as the heat insulating layer 15 formed on the outside of the pan 4 is also formed below the flange portion 9 for holding the pan 4 by hand, when the pan 4 is held during the heat insulation, the flange 4 is conventionally formed. The lower side of the portion 9 is not so heated, and the usability when removing the pan 4 from the inner frame 5 is improved. In addition, since the heat insulating layer 15 can be formed by painting on the lower side of the flange portion 9 at the same time as the outside of the pan 4, a special manufacturing process is not required when the heat insulating layer 15 is formed on the flange portion 9, and the productivity is high. . In addition, the flange 9
There is no step or groove from the lower side to the outside of the pot 4, so that dirt does not enter and the appearance is not deteriorated. Also,
The heat-insulating layer 15 can suppress the temperature rise outside the pan 4 and the lower side of the flange portion 9, and the heat-sensing temperature of the heat-insulating layer 15 is lower than that of the metal surface constituting the pan 4, so that it is practically easy to use.

The present invention is not limited to the above embodiment, and various modifications can be made within the scope of the present invention.

[0038]

According to the first aspect of the present invention, there is provided an electromagnetic induction heating type rice cooker comprising a bottomed cylindrical pot and a pot accommodating portion for accommodating the pan, wherein the pan is mainly made of a metal member. While forming
An insulating layer is formed on the outside of the pot, an outwardly projecting flange is formed on the upper portion of the pot, and the flange portion is mounted on a pan mounting portion provided on the upper portion of the pan receiving portion. When the pan is accommodated, a gap is formed between the entire surface of the heat insulating layer of the pan and the pan accommodating portion, and it is possible to improve the heating efficiency at the time of cooking rice and the heat retention efficiency at the time of keeping the temperature. become.

According to a second aspect of the present invention, there is provided an electromagnetic induction heating type rice cooker, wherein the heat insulating layer is made of a resin material such as a fluorine resin or a silicone resin, or a glass or alumina resin. In this case, it is characterized by mixing the fine and granular inorganic material, in this case, without increasing the size of the pot itself, increasing the heat insulation of the pot, the heating efficiency during rice cooking and the heat retention efficiency at the time of heat retention It is possible to improve the pot, and further, it is possible to remarkably improve the productivity of the pot.

According to a third aspect of the present invention, there is provided an electromagnetic induction heating type rice cooker according to the second aspect, wherein the outer surface of the pot is formed to have a rough surface with irregularities by the heat insulating layer. In addition to being able to easily check for the presence of a heat insulating layer during manufacturing,
The heat retention of the pan and the accommodation in the pan accommodation section can be maintained favorably.

According to a fourth aspect of the present invention, in addition to the configuration of the second aspect, the electromagnetic induction heating type rice cooker further comprises a pot temperature detecting means for detecting the temperature of the pot, which is brought into contact with the outer surface of the pot. The heat insulating layer is not formed on the outer surface of the pot at the contact portion of the pot temperature detecting means, and the temperature of the pot is controlled during cooking and keeping warm while having the heat insulating layer. It is possible to detect with high accuracy.

According to a fifth aspect of the present invention, there is provided an electromagnetic induction heating type rice cooker according to the second aspect, wherein a pot temperature detecting means for detecting the temperature of the pot is brought into contact with the outer surface of the pot. The heat insulating layer on the outer surface of the pot at the contact portion of the pot temperature detecting means is formed thinner than other portions, and the pot is provided with a heat insulating layer when cooking rice or keeping warm. Temperature can be detected with high accuracy, and the productivity at the time of forming the heat insulating layer can be improved.

Further, in the electromagnetic induction heating type rice cooker according to claim 6 of the present invention, in addition to the configuration of claim 1, the pan is removably accommodated from an upper opening of the pan accommodating section. The same heat insulating layer as the outside of the pan is also formed below the flange, so that the usability when the pan is taken out of the pan housing can be improved, and the production when the heat insulating layer is formed on the flange can be improved. The properties and the appearance of the pot can be improved at the same time.

[Brief description of the drawings]

FIG. 1 is an overall sectional view of an electromagnetic induction heating type rice cooker showing one embodiment of the present invention.

FIG. 2 is a cross-sectional view of a main part of the pot with the heat insulating layer formed thereon.

FIG. 3 is a sectional view of a main part of the pot in a state where the upper surface coating layer is formed.

FIG. 4 is a cross-sectional view of a main part of the pot in a case where hollow glass beads are selected as the heat insulating main body.

FIG. 5 is a block diagram showing an electrical configuration of the same.

FIG. 6 is a graph showing timing of heating and time-dependent change of temperature.

[Explanation of symbols]

 4 Pan 5 Inner frame (pan storage section) 8 Pan placement section 9 Flange section 11 Pan main body (main body) 13 Paint (resin material) 14 Thermal insulation main body (inorganic material) 15 Thermal insulation layer 21 Gap 22 Pan temperature sensor (pan temperature detection means)

Claims (6)

[Claims] 1. A pot having a bottomed cylindrical pot and a pot accommodating portion for accommodating the pot, wherein the pot forms a main body with a metal member, and an insulating layer is formed outside the pot, An outwardly protruding flange portion is formed on the upper portion of the pan, and when the flange portion is placed on the pan placing portion provided on the upper portion of the pan accommodating portion to accommodate the pan, An electromagnetic induction heating type rice cooker, wherein a gap is formed between the entire surface of the heat insulating layer and the pot housing portion. 2. The electromagnetic insulating device according to claim 1, wherein the heat insulating layer is formed by mixing a fine granular inorganic material such as glass or alumina into a resin material such as a fluorine resin or a silicone resin. Induction heating rice cooker. 3. The electromagnetic induction heating type rice cooker according to claim 2, wherein the outer surface of the pot is formed as a rough surface with irregularities by the heat insulating layer. 4. A pan temperature detecting means for detecting a temperature of the pan is provided in contact with an outer surface of the pan, and the heat insulating layer is not formed on an outer surface of the pan at a contact portion of the pan temperature detecting means. The electromagnetic induction heating type rice cooker according to claim 2, wherein 5. A pot temperature detecting means for detecting the temperature of the pot is provided in contact with an outer surface of the pot, and the heat insulating layer on the outer surface of the pot at a contact portion of the pot temperature detecting means is provided more than other portions. The electromagnetic induction heating type rice cooker according to claim 2, wherein the rice cooker is also formed to be thin. 6. The pan is removably accommodated in an upper opening of the pan accommodating portion, and the same heat insulating layer as the outside of the pan is formed below the flange. Item 7. An electromagnetic induction heating rice cooker according to Item 1.