JPS6330004B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a control device for an electric rice cooker such as an electric rice cooker, and is particularly suitable for cooking rice porridge in which the boiling temperature is maintained for a predetermined period of time without using a special pot for cooking rice porridge. The purpose is to automatically control the firepower according to the cooking progress of porridge and to perform highly efficient cooking.

In general, when cooking food such as porridge that is kept at around boiling temperature for a predetermined period of time, when heated with a heater that generates a relatively high amount of heat, such as an electric rice cooker, the operating temperature of the built-in heat sensitive element (approximately 140 - 150 degrees)
Until it reaches the boiling temperature, it will be heated continuously even after it reaches the boiling temperature.
There was a drawback that it caused overflow. For this reason, there are some methods that reduce the amount of heat from the heater by installing a special pot for cooking rice porridge and putting water between the pot and the outer pot and heating this water to evaporate it, but as mentioned above, a special pot is used. Therefore, it was expensive, the heat of the heater could not be used effectively, and the start-up was slow.

The present invention aims to improve the above-mentioned drawbacks, and the heater is controlled by the first heat-sensitive element that is in close contact with the inner bottom surface of the inner pot from the start of cooking until the temperature reaches around the boiling temperature, and when the temperature reaches around the boiling temperature, the heater is controlled by the second heat-sensitive element. This is detected by a heat sensitive element, and the subsequent calorific value of the boiling heater is controlled to be smaller than the calorific value of the previous heater. This will be explained below based on the drawings. FIG. 1 shows a schematic cross-sectional view. 1 is a cylindrical frame; 2 is a bottomed cylindrical outer pot built into the frame; 3 is an inner pot that is removably inserted into the outer pot and stores food to be cooked;
Numeral 4 is a ring-shaped boiling heater provided at the inner bottom of the outer pot 2; 5 is provided at the center of the bottom of the outer pot 2; The first heat-sensitive element is energized to be in close contact with the position that most accurately senses the temperature of the food until it reaches the temperature. It is a negative thermistor whose resistance value decreases as the temperature rises, and it is around 70 degrees. The Currie points are set in Reference numeral 7 denotes a rotatable lid body for closing the outer pot 2 and the inner pot 3, which includes an outer lid 8, an inner lid 9 with good heat conduction, a lid packing 10 held between the outer periphery of each lid, and an inner lid. The second heat sensitive body 11 is provided in close contact with the upper surface of 9 (the position where the boiling temperature is accurately detected). A Currie point has been set up nearby. 12
13 is a frame cover that fits and fixes the edge of the upper opening of the frame 1 and the outer pot 2; 14 is fixed to the lower part of the frame 1; The back cover forms a storage chamber 16 for an electronic circuit 15, which will be described later.

Figure 2 shows an electronic circuit, where MC is a microcomputer that has input gates I ₁ and I ₂ and output gate O ₀ and is programmed with predetermined functions, and RY is a built-in contact RYS that is connected to the Relay connected in series to heater 4, E is DC power supply,
STW is a start switch connected in series to the power supply,
BG ₁ is a first bridge circuit that includes the first heat sensitive body 5, one side connects the first heat sensitive body 5 and a resistor _R1 in series, and the other side connects a resistor _R2 and a resistor _R3 in series to provide a reference voltage. Set each connection to the first comparator
The output of the _comparator is connected to one input gate _I1 of the microcomputer MC. BG ₂ is a second bridge circuit that includes the second heat sensitive body 11, one side connects the second heat sensitive body 11 and a resistor _R4 in series, and the other side connects a resistor _R5 and a resistor _R6 in series to provide a reference voltage. and each connection is connected to the input gate of a second comparator CP ₂ , the output of which is connected to another input gate I ₂ of the microcomputer MC. 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 turned on and off via the resistor R ₉ by the output gate O ₀ of the microcomputer MC. There is a driver who does.

Next, we will discuss the operation. First, when cooking rice normally, a predetermined amount of water and rice are stored in the inner pot 3, inserted into the outer pot 2, and the input level is connected to another input gate (not shown) of the microcomputer MC. Operate the selector switch (not shown) to set it to the "cooking" position, then press the start switch.
The STW is turned on to set the temperature detection state of only the first heat sensitive element 5 and perform the rice cooking operation.

To cook porridge, store rice and a large amount of water in the inner pot 3, insert the inner pot into the outer pot 2, operate the changeover switch to set it to the "porridge" position, and press the start switch STW. Turn on. With this ON operation, the microcomputer MC
The output signal of the output gate O ₀ turns on the driver Tr through the resistor R ₉ , drives the relay RY, and closes the contact.
Power is applied to the boiling heater 4 via RYS. This is because the output of the first comparator CP ₁ becomes "H" due to the large resistance value of the first heat sensitive body 5, and in response, the output gate of the microcomputer MC becomes "H".

The temperature of the porridge is determined by the boiling heater 4 as shown in Figure 3.
As the amount of heat directly heats the inner pot 3, it rises rapidly and reaches around 90 degrees, the temperature of the first heat sensitive element 5 reaches about 70 degrees, and the output of the first comparator CP ₁ becomes "H". The first program in the microcomputer MC turns the relay RY ON and OFF at predetermined intervals to slightly reduce the calorific value of the boiling heater 4 and gradually reach the boiling temperature. When the temperature of the porridge reaches the boiling temperature, the amount of steam generated in the inner pot 3 increases, and this steam heats the auxiliary lid 12 and the inner lid 9, so that the temperature of the inner lid reaches about 80 degrees. The resistance value of the second heat sensitive body 11 that senses this temperature increases rapidly, so the output of the second comparator CP ₂ changes from "L" to "H" and is input to the input gate I ₂ of the microcomputer MC and output. Gate O ₀ controls the driver Tr according to the second program to maintain the porridge near the boiling temperature for a predetermined period of time (approximately 20 minutes), and the boiling heater 4 is activated.
``ON'' and ``OFF'' to further reduce the calorific value of
Control. Eventually, after a predetermined period of time has elapsed, the duty of the output of the microcomputer MC is greatly changed to minimize the energization rate of the boiling heater 4 and shift to a warm state. After this predetermined time has elapsed, the heat generation of the boiling heater 4 may be completely stopped if it is not necessary.

As described above, the present invention provides an outer pot, a cylindrical inner pot with a bottom for storing food that can be inserted and removed into the outer pot, and a lid body for covering the outer pot and the inner pot. a boiling heater provided on the inner bottom of the outer pot; a first heat sensitive element provided on the outer pot and always energized to be in close contact with the outer bottom surface of the inner pot; and a second heat sensitive element provided inside the lid. and a heat-sensitive body, the first heat-sensitive body controls the amount of heat generated by the boiling heater until the food to be cooked reaches near the boiling temperature from the start of cooking, and the heating temperature is determined by the first heat-sensitive body until the food to be cooked reaches near the boiling temperature. Detected by the second heat sensitive body,
Since the calorific value of the boiling heater after this is controlled to be lower than the calorific value of the heater before boiling, it is possible to accurately detect the temperature in the entire process, measure effective heat utilization, and prevent overflow. Never. Moreover, since the porridge can be cooked in a single pot, there is no need for a dedicated pot, and the trouble of completely sealing the outer pot is eliminated.

[Brief explanation of the drawing]

FIG. 1 is a schematic sectional view of the electric boiler of the present invention, FIG. 2 is an electric circuit diagram, and FIG. 3 is a characteristic diagram of the food to be cooked. DESCRIPTION OF SYMBOLS 1... Frame, 2... Outer pot, 3... Inner pot, 4... Boiling heater, 5... First heat sensitive body, 7... Lid body, 11...
Second heat sensitive body.

Claims (1)

[Claims] 1. An outer pot, a bottomed cylindrical inner pot for storing food that is removably inserted into the outer pot, a lid for covering the outer pot and the inner pot, and a lid for the outer pot. A boiling heater provided in the inner bottom, a first heat sensitive element provided in the outer pot and energized so as to be in close contact with the outer bottom surface of the inner pot at all times, and a second heat sensitive element provided in the lid body. From the start of cooking until the food to be cooked reaches around the boiling temperature, the first heat sensitive element controls (the amount of heat generated by) the boiling heater, and when the food to be cooked reaches around the boiling temperature, the second A control device for an electric boiler, characterized in that the control device detects the temperature using a heat sensitive body and controls the calorific value of the boiling heater thereafter to be smaller than the calorific value of the heater before boiling.