JP2620680B2 - Electric cooker control device - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a controller for an electric rice cooker such as an electric rice cooker capable of cooking rice porridge and the like.

[0002]

2. Description of the Related Art Conventionally, an electric rice cooker is disclosed in
As disclosed in Japanese Patent Application Laid-Open No. 7-136421, a heat sensitive body is provided at the bottom of the inner pot, and the heater is controlled based on the output of the heat sensitive body. In such an electric rice cooker, good results can be obtained in the detection of the completion of rice cooking and the temperature detection in a low temperature range. Since the temperature distribution of the food greatly depends on the non-uniformity, it is difficult to detect the boiling of the food.

In order to cook rice porridge and the like in an ideal form, it is necessary to accurately detect the boiling of the object to be cooked. I couldn't do that.

[0004]

SUMMARY OF THE INVENTION In view of the above-mentioned drawbacks, the present invention is intended to accurately detect boiling, reduce the size and weight of a lid, and protect an electronic circuit.

[0005]

According to the present invention, there is provided an outer pot and an inner pot for storing an object to be cooked which is removably provided in the outer pot.
A device having a lid for covering the outer pan and the inner pan, and a cooking heater for heating the inner pan, and detecting the boiling of the object to be cooked and adjusting the calorific value of the cooking heater. In the above, a thermosensitive body made of a thermistor whose resistance value changes according to temperature is provided in the lid body, and an electronic circuit electrically connected to the thermosensitive body is provided on a member side for storing the outer pan, and a resistance value of the thermosensitive body is provided. The electronic circuit performs the boiling detection based on the change, and after the boiling is detected, the electronic circuit changes the heat value of the cooking heater for a predetermined time so as to maintain the temperature of the object to be cooked near the boiling temperature for a predetermined time. After a predetermined time,
At the time of shifting to the heat retaining state, the heating of the cooking heater is stopped.

[0006]

A thermosensitive element made of a thermistor whose resistance value changes with temperature is provided in the lid, and an electronic circuit electrically connected to the thermosensitive element is provided on the side of the member that houses the outer pan, so that the resistance value of the thermosensitive element changes. Based on the electronic circuit, accurate boiling detection is performed to prevent overflow after boiling.

Further, after detecting the boiling, the electronic circuit lowers the calorific value of the cooking heater for a predetermined time so as to maintain the temperature of the food to be kept near the boiling temperature for a predetermined time, and then shifts to a heat retaining state. By stopping the heat generation of the cooking heater, the electronic circuit is not affected by the steam, and the α-formation of rice is promoted to prevent gelatinization.

[0008]

An embodiment of the present invention will be described with reference to the drawings.
FIG. 1 is a schematic sectional view of the electric cooker of the present invention.

1 is a cylindrical frame, 2 is a cylindrical outer pan with a bottom provided inside the frame, 3 is an inner pan which is removably inserted into the outer pan and stores the food, and 4 is A ring-shaped cooking heater 5 provided at the inner bottom portion of the outer pan 2 is provided at the center of the bottom surface of the outer pan 2 and the inner pan 3 is constantly operated by a spring 6.
The first thermosensitive element urged in close contact with the outer bottom surface (the position where the temperature of the object to be cooked is most accurately detected until the object reaches the boiling temperature). Has a Curie point around 70 degrees.

Numeral 7 denotes a rotatable lid for covering the outer pan 2 and the inner pan 3, and a lid packing 10 sandwiched between the outer pan 8 and the inner pan 9 having good heat conduction and the outer peripheral edge of each lid. And a second thermosensitive body 11 provided in close contact with the upper surface of the inner pan 9 (a position at which the boiling temperature is accurately detected). The thermosensitive body is a positive thermistor whose resistance value changes with a rise in temperature. The Curie point is set at about 80 degrees.

Reference numeral 12 denotes an auxiliary lid provided so as to be freely attached to the lower surface of the lid 7, reference numeral 13 denotes a frame cover for fitting and fixing the edges of the upper opening of the frame 1 and the outer pan 2, and reference numeral 14 denotes the frame 1 A housing 16 for an electronic circuit 15 described later is formed by a back cover fixed to a lower part of the electronic circuit 15.

FIG. 2 shows an electronic circuit connected to the first and second thermal elements 5 and 11.

MC is an input gate I ₁₉ I ₂ and an output gate O _0.
A microcomputer programmed with predetermined functions, RY is a relay in which a built-in contact RYS is connected in series to the cooking heater 4, E is a DC power supply,
STW is a start switch connected in series with the power supply, BG
₁ is a first bridge circuit including said first heat sensing element 5, setting a reference voltage to one side is connected in series to resistor R ₁ and the first susceptor 5 Tahen resistor R ₂ and the resistor R ₃ connected in series Each connection is connected to the input gate of the _first comparator CP1, and the output of the comparator is connected to the microcomputer MC1.
It is connected to one input gate I ₁ of.

BG ₂ is a second bridge circuit including the second heat sensitive element 11. One side is connected in series with the second heat sensitive element 11 and the resistor R ₄ , and the other side is connected in series with the resistor R ₅ and the resistor R _6. Set the reference voltage and connect each connection to the second comparator CP ₂
The output of the comparator is connected to another input gate I of the microcomputer MC.
Connected to ₂ . R ₇ and R ₈ are feedback resistors connected to the output gates of the respective comparators, and _Tr is connected in series to the relay RY and connected to the microcomputer MC.
Is a driver which is turned on / off by the output gate O ₀ via the resistor R ₉ .

Next, the operation will be described. First, when ordinary rice is cooked, a predetermined amount of water and rice are stored in the inner pot 3, inserted into the outer pot 2, and an input level connected to another input gate (not shown) of the microcomputer MC. By operating a changeover switch (not shown), the rice is set to the “rice cooking” position, the start switch STW is turned on, and the temperature of only the first thermosensitive element 5 is detected to perform the rice cooking operation. Here, when cooking porridge, rice and a large amount of water are stored in the inner pan 3, the inner pan is inserted into the outer pan 2, and the changeover switch is operated to set the rice porridge to the "porridge" position, and the start switch STW O
Set to N.

The output signal of the output gate O ₀ of the microcomputer MC accompanying this ON operation is turned on by the driver _Tr via the resistor R ₉ , the relay RY is driven, and the contact R
Electricity is supplied to the cooking heater 4 via YS.

[0017] This is the output of the first Compartment aerator CP ₁ due to the large resistance value of the first thermosensitive element 5 becomes "H",
In response to this, the output gate of the microcomputer MC becomes "H".

The temperature of the porridge is as shown in FIG.
When the amount of heat rapidly reach the vicinity of elevated approximately 90 degrees from the heating directly in the pot 3, the temperature of the first heat sensing element 5 is output to about 70 degrees is reached by the first Compartment aerator CP ₁ is "H" To "L", and the relay RY is turned "ON" and "O" at predetermined intervals by a first program in the microcomputer MC.
FF "to slightly lower the calorific value of the cooking heater 4 to gradually reach the boiling temperature. When the temperature of the rice porridge reaches the boiling temperature, the amount of steam generated in the inner pan 3 rapidly increases, and this steam heats the auxiliary lid 12 and the inner lid 9 to reach about 80 degrees. Second susceptor 11 which senses the temperature output of the resistance value increases abruptly second Compur chelator CP ₂ is input from "L" to the input gate I ₂ of the "H" microcomputer MC outputs gate O ₀
The second program controls the driver _Tr to maintain the boiling temperature of the porridge near the boiling temperature for a predetermined time (about 20 minutes), so that the calorific value of the heating heater 4 is further reduced by "O".
N "and" OFF "control. Eventually, after a lapse of a predetermined time, the output duty of the microcomputer MC is greatly changed, and the energization rate of the cooking heater 4 is minimized to shift to the heat retaining state. After the lapse of the predetermined time, the heat generation of the cooking heater 4 is stopped.

[0019]

As described above, according to the present invention, since the heat-sensitive body composed of the thermistor is provided in the lid, the influence of heat from the cooking heater is reduced, and accurate temperature detection can be performed. When cooking foods with a lot of moisture, such as porridge, it is possible to accurately detect the boiling of the object to be cooked, prevent overflowing due to overheating after the boiling, and compare with a thermosensitive body composed of a thermostat. The lid can be made lighter and smaller.

Furthermore, since the electronic circuit electrically connected to the thermosensitive element for detecting boiling is provided not on the cover but on the member for storing the outer pan, it is possible to reduce a failure due to the influence of steam. it can. Further, after the boiling is detected, the calorific value of the cooking heater is reduced for a predetermined time so that the temperature of the food is kept near the boiling temperature for a predetermined time.
It is possible to maintain the high temperature near the boiling temperature that is optimal for the formation for a predetermined time, promote the α-formation, and cook the rice porridge without the core deliciously. Furthermore, since the heating of the boiler heater is stopped after the above-mentioned predetermined time, gelatinization of the porridge due to heat retention can be reliably prevented, and porridge cooking can be performed satisfactorily.

[Brief description of the drawings]

FIG. 1 is a schematic cross-sectional view of an apparatus main body on which a control device for an electric cooker of the present invention is mounted.

FIG. 2 is an electric circuit diagram.

FIG. 3 is a characteristic diagram of an object to be cooked.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Frame 2 Outer pot 3 Inner pot 4 Heater for cooking 5 First heat-sensitive body (heat-sensitive body) 7 Lid 11 Second heat-sensitive body 14 Back cover 15 Electronic circuit 16 Storage room MC Microcomputer

Claims (1)

(57) [Claims] 1. An outer pan, an inner pan for storing an object to be cooked which is detachably inserted in the outer pan, a lid for covering the outer pan and the inner pan, and heating the inner pan. Having a heater for cooking
In the apparatus for detecting the boiling of the food to be cooked and adjusting the calorific value of the cooking heater, a heat-sensitive body comprising a thermistor whose resistance value changes according to the temperature is provided in the lid body, and a member side for storing the outer pan An electronic circuit electrically connected to the heat-sensitive body is provided, and the electronic circuit performs boiling detection based on a change in the resistance value of the heat-sensitive body. The amount of heat generated by the cooking heater is reduced for a predetermined time so as to maintain the temperature near the boiling temperature for a predetermined time, and after the predetermined time, the heat generation of the cooking heater is stopped when shifting to a warming state. Control device for electric cooker.