JPH0866298A - Electromagnetic rice cooker - Google Patents

Abstract

PURPOSE: To improve responsiveness by unnecessitating the embedding of a temperature fuse into a sensor holder part by providing the temperature fuse on the lower surface side of a thin part formed on the lower surface side of the bottom of an inner case. CONSTITUTION: One part of an inner case bottom 3a is formed into a thin part 30, and a temperature fuse 15 is provided on the side of a lower surface 30a of the thin part 30. Thus, it is not necessary to embed any large temperature fuse on the side of a center sensor 22 like the conventional rice cooker, the rice cooker can be miniaturized and can reduce heat capacity, dispersion in the uneven accuracy on the upper surface of a sensor cap is reduced, the accuracy of adhesion with the surface of a bottom 2a of an inner pan 2 is improved as well, and the temperature detecting performance of first and second thermistors 23 and 24 is improved, too. Further, since one part of the inner case bottom 3a as a work coil installing part is formed into the thin part 30 adjacently to the inner pan 2, when the temperature of the inner pan 2 is made abnormal, the abnormal temperature is detected by easily transmitting that head through the thin part 30 to the temperature fuse 15. Therefore, even when the temperature fuse is put into an insulated tube, responsiveness is improved.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an electromagnetic rice cooker having an abnormal temperature detecting function.

[0002]

2. Description of the Related Art In general, an electromagnetic rice cooker detects an abnormal temperature state by fusing when an inner pot temperature reaches an abnormal temperature higher than a predetermined value, and supplies power to a work coil and a microcomputer. A thermal fuse to shut off is provided.

Conventionally, the thermal fuse is provided inside a center sensor at the center of the inner case, in parallel with a temperature sensor such as a thermistor. The center sensor is configured to have a sensor cap with high heat conductivity at the top, and is configured to contact the bottom of the inner pot via the sensor cap. Therefore, the temperature sensor and the temperature fuse respectively detect the temperature of the inner pot via the sensor cap.

The temperature sensor variably controls the heat generation amount of the inner pot by the work coil according to the detected temperature of the inner pot, while the temperature fuse controls the temperature of the inner pot to be an abnormal temperature set in advance. When it reaches, the power supply to the work coil and the microcomputer is cut off to prevent abnormal heating.

[0005]

As described above, in the conventional electromagnetic rice cooker, a temperature fuse is buried at the upper end of the center sensor to detect an abnormal temperature of the inner pot and to supply power to the work coil and the like corresponding thereto. I was trying to shut off.

However, when such a structure is adopted, the following problems occur.

(1) Since the size of the thermal fuse is considerably large, the diameter of the upper end portion of the sensor holder of the center sensor must be considerably large.

(2) If the diameter of the upper end of the sensor holder is large, the degree of adhesion of the contact surface with the bottom portion of the inner pot via the sensor cap is deteriorated due to unevenness in unevenness or the like. As a result, the temperature detection performance decreases.

(3) The structure of the sensor holder becomes complicated, and the number of processes for assembling and assembling increases, resulting in high cost.

(4) The thermal fuse must be insulated from the surroundings, and must be housed and buried in an insulating tube, so that the response is poor.

(5) The fusing of the member due to the abnormal temperature
Originally, the area around the work coil is the most problematic.

The present invention has been made to solve these problems, and a sensor of a center sensor is formed by forming a thin portion on the lower surface side of the bottom of the inner case and providing a temperature fuse on the lower surface side of the thin portion. It is an object of the present invention to provide an electromagnetic rice cooker that does not require embedding a temperature fuse in a holder portion and has good response.

[0013]

SUMMARY OF THE INVENTION The present invention is provided with the following means for solving the problems in order to surely solve the above-mentioned conventional problems and effectively achieve the object.

That is, the electromagnetic rice cooker according to the present invention comprises a container body composed of an inner case and an outer case, a work coil provided on the lower surface side of the inner case in the container body, and a coil for supporting the work coil from below. In an electromagnetic rice cooker comprising a table and an inner pot stored in the inner case,
A part of the bottom of the inner case is formed into a thin portion, and a thermal fuse is provided on the lower surface side of the thin portion.

Further, in the electromagnetic rice cooker of the present invention, in the above configuration, an opening facing the lower surface of the thin portion of the upper inner case is formed in the coil base portion vertically corresponding to the thin portion of the inner case. The thermal fuse held by the thermal fuse holder from below through the opening is detachably mounted.

Further, in the electromagnetic rice cooker of the present invention, in each of the above-described configurations, a center sensor having a built-in abnormal temperature detection sensor is provided at the center of the inner case, and the abnormal temperature detection sensor in the center sensor is provided. The microcomputer controls the microcomputer to stop the operation of heating the inner coil of the work coil by the abnormal temperature detection signal, while shutting off all power supply circuits including the work coil and the microcomputer when the thermal fuse is blown. .

[0017]

In the electromagnetic rice cooker of the present invention, the following actions are realized corresponding to the configuration.

That is, in the configuration of the electromagnetic rice cooker of the present invention, as described above, the container body including the inner case and the outer case, the work coil provided on the lower surface side of the inner case in the container body, and the work coil An electromagnetic rice cooker comprising a coil base for supporting the inner case from below and an inner pot accommodated in the inner case, wherein a part of the bottom of the inner case is formed in a thin portion and a temperature is formed on the lower surface side of the thin portion. Since a fuse is provided, it is not necessary to bury a large thermal fuse on the center sensor side.

Therefore, the size (diameter) of the upper end of the sensor holder can be reduced, and the accuracy of close contact with the inner pot (the accuracy of heat transfer) can be improved. Therefore, the temperature detection performance of the temperature sensor is also improved.

Further, the structure inside the center sensor, which is the work coil installation portion, is simplified, the processing and assembling are improved, and the cost is reduced.

Further, since a part of the bottom of the inner case is formed in a thin portion, when the temperature of the inner pot becomes abnormal, the heat is easily transmitted to the thermal fuse through the thin portion to detect the abnormal temperature. Is done. Therefore, the responsiveness is high even in the insulating tube.

In this case, an opening facing the lower surface of the thin portion of the upper inner case bottom is formed in the lower coil base corresponding to the thin portion of the inner case bottom, and the opening is formed through the opening. When the thermal fuse held in the thermal fuse holder is detachably mounted from below, the thermal fuse can be easily assembled at the time of assembly and the thermal fuse once blown can be easily replaced.

Further, in these configurations, a center sensor having an abnormal temperature detection sensor is provided in the center of the inner case, and first, an abnormal temperature detection signal of the abnormal temperature detection sensor of the center sensor is used to first work coil of the microcomputer. While stopping the heating control operation of the inner pot by the above, when the temperature fuse is blown, all power circuits including the work coil and the control circuit such as the microcomputer are shut off, and the set values are different. If the abnormal temperature detection and detection system of is realized, the power supply to the work coil can be cut off before the final melting of the thermal fuse, thereby eliminating the waste of the thermal fuse.

If there is any abnormality in the abnormal temperature detection sensor that can be operated repeatedly without replacing the thermal fuse, or if the microcomputer goes out of control, the thermal fuse is finally terminated. The fusing operation surely shuts off the power supply to the work coil and the microcomputer, so that absolute safety can also be secured.

[0025]

As a result of the above, according to the present invention, it is possible to improve the temperature detection performance of the center sensor portion and to simplify the structure and reduce the cost.

Further, the responsiveness of the thermal fuse itself can be improved, and assembling and replacement become easy.

Further, when a temperature fuse and an abnormal temperature detection sensor are combined and the abnormal temperature reference value of the abnormal temperature detection sensor is set lower than the operation set temperature of the temperature fuse, the abnormal temperature detection sensor can be used except when the abnormal temperature detection sensor fails. There is almost no need to operate the thermal fuse, and the need to replace the thermal fuse is reduced except when the abnormal temperature detection sensor fails or the microcomputer runs away.

[0028]

【Example】

(Embodiment 1) FIGS. 1 to 4 show the configuration of an electromagnetic rice cooker according to an embodiment of the present invention.

First, the electromagnetic rice cooker 1 of this embodiment is configured to serve, for example, both rice cooking and heat retention. And
For example, as shown in FIGS. 1 and 2, an inner pot (rice cooker) 2 made of stainless steel or the like capable of generating heat by eddy current inside.
And a cylindrical main body 3 made of a synthetic resin and having a bottom and a cylindrical outer case 4 supporting the inner case 3. A lid unit 5 is provided on the upper part of the container body so as to be openable and closable.

The bottom 3a of the inner case 3 is shown in FIGS.
As shown in FIG. 2, the work coils 7a and 7b of the inner and outer two sets can be fitted with the first and second concentric ribs 91 and 92 at predetermined intervals.
The a and 7b are joined to the radially inner and outer fitting surfaces via the first and second ribs 91 and 92 with an adhesive agent.

The outer case 4 includes a cylindrical cover 4a formed of a synthetic resin plate, a synthetic resin shoulder 4b coupled to an upper end of the cover 4a, and a cover 4a. A bottom portion 4c made of synthetic resin connected to a lower end portion forms a bottomed cylindrical shape with a space 6 having a predetermined width formed between the bottom portion 3a of the inner case 3 and the bottom portion 3a of the inner case 3. The inner case (protective frame) 3 made of synthetic resin and having a bottomed cylindrical shape for setting the inner pot 2 so as to be able to be taken out as described above is supported. First and second ribs 91, 91 partitioning between the work coils 7a, 7b on the outer peripheral portion of the bottom 3a of the inner case 3.
A thin portion 30 having a concave portion is formed on the lower surface side in a portion between 92, and the lower surface side of the thin portion 30 includes work coils 7a, 7b and a microcomputer when abnormal heating occurs as described later. Rice cooker control unit 61 (described later)
A thermal fuse 15 for shutting off power to the power supply is provided. Further, the work coils 7a and 7b and the coil base 8 are provided below the bottom portion 3a of the inner case 3 so as to be vertically positioned. An operation panel section 120 is provided on the front side of the cover section 4a of the outer case 4, and an operation board 100 provided with the rice cooker control unit 61 and the like is provided on the back side thereof.

In the lower part of the coil base 8, there is provided a power supply for controlling the energization amount of the work coils 7a and 7b by a rice cooker control unit (see reference numeral 61 in FIG. 5) comprising a microcomputer on the operation board 100 side. A control board 36 having a control circuit is provided.

The coil base 8 has a work-coil supporting portion 8a which has a saucer-shaped inner case supporting surface and supports the work coils 7a and 7b.
It is composed of a ferrite core fitting groove 9, 9 formed on the upper side of the outer case bottom 4c and a leg portion 10, 10 provided at a lower portion of the work coil supporting portion 8. Supported by. On the outer peripheral surface of the side of the work coil supporting portion 8a of the coil base 8, a pair of vertical wall structures are provided on both sides of one end (outer peripheral end) of the ferrite core fitting groove 9, 9 ,. Spacers 11 and 11 are provided, and a ring-shaped magnetic shield plate 12 is fitted and fixed from the lower side to the outer periphery of the spacers 11 and 11 with a predetermined gap maintained therebetween.

Further, the ferrite core fitting grooves 9, 9
······································· is formed in a state of extending in the radial direction with a circumferential interval of 90 degrees therebetween, and also penetrating in the vertical direction. • is fitted.

Further, as shown in detail in FIG. 3, an opening 80 having a predetermined diameter is formed in a portion of the coil base 8 corresponding to the thin portion 30 of the inner case bottom 3a. The temperature fuse holder 14 having an H-shaped cross section standing up above the work coil supporting portion 8 via
Is detachably attached, and the thermal fuse holder 14 supports the cylindrical thermal fuse 15 in an insulating tube in a state of contacting the lower surface 30a of the thin portion 30 of the bottom portion 3a of the inner case 3. ing.

That is, the thermal fuse holder 14 is provided with the thermal fuse 1 in the concave portion 14a on the upper end side of the holder having the H-shaped cross section.
5 and a part of the lower side wall is bent outwardly in the horizontal direction so as to be attached to the lower surface of the coil base 8.
The mounting portion 14b is fixed to the lower surface of the coil base 8 with a screw 81 from the lower side in a detachable state by fastening it with screws 81.

On the other hand, the bottom part 3a and the side wall part 3b of the inner case 3 are integrally formed, and the center part of the bottom part 3a and the center part of the work coil support part 8a of the coil stand 8 are concentrically penetrated in the vertical direction. A storage space portion (fitting insertion hole) 17 for the center sensor 16 is formed. The center sensor storage space portion 17 is vertically movable up and down in the center sensor storage space portion 17 and constantly urged upward by a coil spring 18. In this state, a center sensor 22 for detecting the set state of the inner pot is provided.

The center sensor storage space 17 is formed in a cylindrical body 19 formed by ribs extending in both the upper and lower directions at the center of the coil stand 8, and a sensor cover 20 is fitted into a lower opening thereof. , Screws 21 are fixed to the pressure wall portion on one side of the cylinder body 19 on the coil stand 8 side.

As shown in detail in FIG. 4, for example, the center sensor 22 is provided with a large-diameter thermal fuse for detecting an abnormal temperature as in the prior art at a sensor holding portion 94 at the upper end inside the cylindrical sensor holder 22a. Is not provided, and only the first and second thermistors (temperature sensors) 23 and 24 for detecting the temperature of the inner pot 2 which are considerably smaller than the temperature fuse are provided in parallel at the center. At the same time, the upper surface of the sensor holder 94 at the upper end of the sensor holder 22a is far larger than the conventional one, which is sufficient to cover the small-diameter sensor holder 94 provided with only the small first and second thermistors 23 and 24. A sensor cap 25 made of a small-diameter metal material having good thermal conductivity is fitted and fixed integrally. Then, the upper side edge portion 2 of the cylindrical sensor holder 22a
The lower part 6 is fitted with a ring-shaped shield member 93 provided with a lip portion 93a for shielding in the circumferential direction, and a coil interposed between the shield member 93 and the cover surface 27 of the lower sensor cover 20. The entire sensor holder 22a is supported by a spring 18 so as to be able to move up and down and to be constantly urged upward.

Sensor holder 9 in the sensor holder 22a
The lower portion 94a of the fourth sensor cover 4 extends downward by a predetermined length in the shape of a rectangular tube to form a reed switch mounting portion 96 at the lower end, while a cylindrical magnet mounting portion 95 is formed on the lower sensor cover 20.
Are formed. Then, the magnet 28 attached to the upper end of the magnet attachment portion 95 and the reed switch 29 attached to the reed switch attachment portion 96,
The reed switch 29 is turned on and off by moving the sensor switch 22a up and down in accordance with the elevating operation of the sensor holder 22a.
The ON and OFF signals are used to detect the non-set and set states of the inner pot 2. The reference numeral 34 indicates the sensor holder 2 on the bottom 3a of the inner case.
2a is a rising position regulating edge portion, and the edge portion 34 stands up a predetermined height above the upper surface of the inner case bottom portion 3a so that water or the like does not easily enter the sensor housing space portion 17. I have.

In the case of this embodiment, the inner pot 2 has an upper edge 2b on the inner pot supporting edge 83 inside the shoulder 4b of the outer case 4 and has heat resistance and a low coefficient of friction. It is supported by being locked via a high support member 84.

As described above, in the structure of this embodiment, a part of the inner case bottom 3a is formed in the thin portion 30, and the thermal fuse 15 is provided on the lower surface 30a side of the thin portion 30. Therefore, it is not necessary to bury a large thermal fuse on the side of the center sensor 22 unlike the related art. That is, the sensor holding portion 94 of the sensor holder 22a
Since only the first and second thermistors 23 and 24 are installed in the sensor holder 22a,
In addition, the size of the sensor cap 25 can be considerably reduced as compared with the related art, so that the heat capacity of the sensor cap 25 itself can be reduced, and the unevenness of the unevenness on the upper surface of the sensor cap 25 is reduced. The accuracy of thermal coupling (adhesion accuracy) with the bottom 2a surface is also improved, and the temperature detection performance of the first and second thermistors 23 and 24 is also improved.

Further, the structure inside the center sensor 22 is simplified, the processing and assemblability are improved, and the cost is reduced.

Further, since the inner wall 2 is close to the inner pan 2 and a part of the inner case bottom 3a which is the work coil installation portion is formed in the thin portion 30, when the inner pan 2 reaches an abnormal temperature, the heat is generated. An abnormal temperature is detected by being easily transmitted to the thermal fuse 15 via the thin portion 30. Therefore, the responsiveness is high even in the insulating tube. The thermal fuse 15 preferably operates at a lower temperature than the thermal fuse provided in the conventional center sensor 22, for example.

In that case, the inner case bottom 3
In the lower coil base 8 portion corresponding to the thin portion 30 of a,
An opening 80 is formed facing the lower surface 30a of the thin portion 30 of the upper inner case bottom 3a, and the thermal fuse 15 held by the thermal fuse holder 14 is detachably attached from below through the opening 80. Therefore, it becomes easy to assemble the thermal fuse 15 at the time of assembly and to replace the thermal fuse 15 once blown.

Further, in the case of the above configuration, the following merits are brought about as compared with the case where the temperature fuse is provided in the center sensor 22 portion, for example.

That is, in the case of the center sensor 22 portion, when foreign matter such as rice grains enters the upper portion of the sensor cap 25, the heat transfer performance is greatly changed and the operation performance is affected. When the thermal fuse 15 is provided on the lower surface side of 3a, such an influence is not exerted, and a constant and stable operation performance can always be ensured.

The thermal fuse installation section divides the work coils 7a and 7b into two sets, the inner side and the outer side in the radial direction, to make the heat distribution of the inner pot 2 wide and uniform. Since there is no temperature gradient between the ribs 91 and 92 and there is no influence of external temperature on the central temperature distribution portion, it is possible to detect the inner pot temperature accurately and stably.

The first and second thermistors 23,
Reference numeral 24 indicates that the first thermistor 23 is used to control the duty of the work coils 7a and 7b, and the second thermistor 24 is used for detecting abnormal temperature, as is apparent from the control circuit of FIG. (This point will be described later).

On the other hand, the lid unit 5 has an outer cover 37 made of a synthetic resin,
The inner pot 2 of the lid unit 5 fitted inside the outer peripheral edge of the
Is formed in a hollow structure by an inner frame portion 38 made of synthetic resin and a heat radiating plate 57 fitted in the inner frame portion 38, which constitutes an engaging portion to the outer cover 37 and the heat radiating plate 57. Is
The outer peripheral edges are mutually connected via the inner frame 38. The lid unit 5 is rotatably attached to the shoulder portion 4b of the outer case 4 via a hinge mechanism 40, and its open end side is engaged with a predetermined position of the lid unit 5. A lock lever 39 for opening and closing the lid unit 5 is provided.

In addition, approximately at the center of the lid unit 5,
The vapor discharge port 43 is formed so as to penetrate vertically.
A rubber packing 45 is provided in the steam discharge port 43.
Are fitted and the vapor discharge cylinder 44 is attached via the packing 45.

Next, FIG. 5 shows the configuration of a control circuit section centered on the rice cooker control unit of the electromagnetic rice cooker.

In the figure, reference numeral 61 denotes a rice cooker control unit provided on the operation board 100 on the back side of the operation panel section 120 on the front side of the outer case 4, and the rice cooker control unit 61 is mainly composed of a microcomputer and a detection circuit. Unit, a control circuit unit, an oscillation circuit unit, and the like. The detection circuit unit includes, for example, the first and second thermistors 2.
The inner pot temperature detection values T by 3, 24 are respectively input.

Reference numeral 62 is the second thermistor 2 described above.
A temperature detection voltage V ₂ corresponding to the resistance value change of the 4 input through the resistor r _3, abnormal temperature criteria are set on the basis of pre Ji because experimental value voltage _{Vs [Vs = {r 2 /} (r 1 + r ₂ )} × (+ B)] and outputs an oscillation operation stop signal to the oscillation circuit when the temperature detection voltage V ₂ becomes equal to or higher than the abnormal temperature reference voltage Vs. Reference numeral 62 functions as an operation stop control circuit of an inverter circuit that drives the work coils 7a and 7b. The temperature detection voltage V ₁ of the first thermistor 23 is:
It is adapted to be supplied to the control circuit section for controlling the heating amount through the A / D converter of the rice cooker control unit 61. The comparator 62 is configured as an independent circuit separate from the control circuit unit.

In the conventional configuration, as described above, the inner pot 2
A first thermistor 2 serving as a temperature sensor for detecting the temperature of the bottom 2a;
It is arranged to convert the electric signal into an electric signal by only 3 and detect it, and to transmit the detected signal to the control circuit section (in the microcomputer section) for the usual heating amount control to control the heat generation temperature. However, in the control of the IH rice cooker as in the present embodiment, in the process of generally controlling the temperature,
Although the temperature can be controlled in this way, on the other hand, when the temperature of the bottom of the inner pot 2 rises abnormally in the process of controlling with a timer, etc., or when an abnormality such as a microcomputer runaway occurs, the abnormal temperature is detected. Becomes impossible. For this reason, in the conventional configuration, the center sensor 22
Although a large-diameter temperature fuse is provided side by side with the first thermistor 23 in such a portion, when such a configuration is adopted, as described in the above-mentioned conventional problems (1) to (4). There are disadvantages.

Therefore, as described above, the first thermistor 23
The inner pan temperature detection signal V ₁ from the second thermistor 2 is input to the control circuit section for controlling the heating amount.
The inner pot temperature detection signal V ₂ of 4 is input to the comparator 62, which is a temperature determination means other than the microcomputer control other than the heating amount control circuit section, and only when an abnormal temperature higher than a predetermined temperature occurs, the inverter circuit The oscillation operation of is stopped.

With such a configuration, the center sensor 22 having a further increased detection accuracy due to the miniaturization of the sensor cap 25 by removing the large-diameter temperature fuse as described above.
The by second thermistor 24 by anomaly temperature detection value V ₂ detected with high accuracy regardless of the control state or failure of the microcomputer control circuit unit, to stop the oscillation of reliably and compulsorily inverter circuit it can. Therefore,
As a result, the alternating magnetic field from the work coils 7a and 7b can be stopped quickly, and more secure safety is ensured. In addition, as a result, abnormal heating can be stopped early before fusing of the thermal fuse 15 depending on how to set the reference temperature, and the thermal fuse 15 provided on the coil base 8 side, which is necessary for safety standards, can be replaced. It can be made almost unnecessary. The abnormal temperature is detected by automatically releasing the oscillation stop signal output and restarting the oscillation of the inverter circuit when the temperature of the inner pot 2 detected by the second thermistor 24 falls to a safe state. Alternatively, it may be started, or on the other hand, the oscillation operation may not be started again unless the lock is released again such as once locked and reset.

As described above, the second thermistor 24 and the comparator 62, which are independent of the control circuit section of the microcomputer, are provided.
An abnormal temperature detection determining means is provided, and the abnormal heating state is detected as early as possible by the temperature detected by the second thermistor 24 serving as an abnormal temperature detection sensor.
If the heating operation of the a and 7b is stopped, the replacement of the thermal fuse 15 can be made unnecessary. Then, at the time of abnormal heating, the abnormal temperature can be reliably detected, and higher safety can be ensured. As a result, the number of parts of the sensor unit can be reduced, and the cost can be reduced by reducing the number of processing and assembling steps.

Further, since abnormal temperature detection is originally the final means for ensuring safety, it is necessary to always ensure reliable temperature detection performance.

In that sense, for example, a single thermistor 2
In the case where the heating temperature control 3 is used for both the heating temperature control and the abnormal temperature detection control, some handicap occurs in durability and reliability.

Further, it is difficult to select characteristics according to the control purpose, and the circuit structure becomes complicated in terms of signal processing.

However, as in the present embodiment, the remaining space from which the temperature fuse 15 of the sensor holder 22 is removed is effectively used, and in addition to the first thermistor 23 dedicated to the heating amount control, it is further dedicated to abnormal temperature detection. Providing the second thermistor 24 facilitates selection of the temperature detection characteristic according to the control purpose, and improves reliability and durability against failure without complicating the circuit configuration in design. It becomes possible.

Moreover, since there are only two sets of thermistors, the probability of failure is low, and even in the worst case, at least either the heating amount reduction control by the heating amount control or the energization cutting by the abnormal temperature detection can be secured. .
Therefore, the need to replace the thermal fuse can be eliminated as much as possible.

Moreover, since the thermistor is generally much smaller than the thermal fuse, the sensor cap portion can be downsized.

[Brief description of drawings]

FIG. 1 is a central vertical cross-sectional view showing a configuration of an electromagnetic rice cooker according to an embodiment of the present invention, which is cut left and right at a central portion in the front-rear direction.

FIG. 2 is a longitudinal sectional view of a central portion of the electromagnetic rice cooker cut in a front-rear direction at a central portion in a left-right direction.

FIG. 3 is an enlarged sectional view of a thermal fuse section of the electromagnetic rice cooker.

FIG. 4 is an enlarged sectional view of a center sensor portion of the electromagnetic rice cooker.

FIG. 5 is a control circuit diagram of the electromagnetic rice cooker.

[Explanation of symbols]

1 is an electromagnetic rice cooker, 2 is an inner pot, 3 is an inner case, 3a is an inner case bottom, 4 is an outer case, 5 is a lid unit, 7a and 7b are work coils, 8 is a coil stand, 14 is a temperature fuse holder, 15 is a thermal fuse, 23 is a first thermistor,
Reference numeral 24 is a second thermistor, 30 is a thin wall portion, 37 is an outer cover, 38 is an inner frame portion, 43 is a steam discharge port, 43 is a steam discharge cylinder, 61 is a rice cooker control unit, and 62 is a comparator.

Claims (3)

[Claims] 1. A container body including an inner case and an outer case, a work coil provided on a lower surface side of the inner case in the container body, a coil table for supporting the work coil from below, and An electromagnetic rice cooker comprising an inner pot to be stored, wherein a part of the bottom of the inner case is formed in a thin portion and a temperature fuse is provided on a lower surface side of the thin portion. 2. An opening facing the lower surface of the thin portion of the upper inner case is formed in the coil base portion corresponding to the upper and lower portions of the thin portion of the inner case, and a temperature fuse holder is provided from the lower side through the opening. 2. The electromagnetic rice cooker according to claim 1, wherein the held thermal fuse is detachably attached. A center sensor having a built-in abnormal temperature detection sensor is provided at the center of the inner case, and a microcomputer controls heating of the inner pot of the work coil by a microcomputer based on an abnormal temperature detection signal of the abnormal temperature detection sensor in the center sensor. 3. The electromagnetic rice cooker according to claim 1, wherein the operation is stopped, and all the power supply circuits including the work coil and the microcomputer are shut off when the thermal fuse is blown. .