JPH0220899B2 - - Google Patents

Description

Detailed Description of the Invention <Industrial Application Field> The present invention is a heating cooking method in which a temperature sensor is provided at the bottom of a cooking container, and temperature control such as oil temperature for frying is performed based on the temperature detected by the temperature sensor. Regarding a control device.

<Prior art> In a conventional heating cooker, for example, a gas stove for cooking fried foods such as tempura, a temperature sensor is provided in contact with the bottom of the cooking container, and the heating means is adjusted based on the temperature detected by the temperature sensor. There is one in which the cooking temperature (oil temperature in this example) is controlled by controlling the amount of heat of the burner. In this case, the optimal oil temperature is determined by the cooking ingredients, etc., but on the other hand, what the temperature sensor detects is the temperature at the bottom of the cooker, which is affected by the heat of the burner, so the temperature detected by the temperature sensor is actually higher than the oil temperature. Therefore, in order to maintain the oil temperature at the optimum temperature, the operating temperature, which is the standard for switching the heating capacity of the burner, is usually set to a higher temperature than the appropriate oil temperature. For example, if you want to maintain the optimum oil temperature at 160℃, the operating temperature is 164℃.
temperature control is performed based on this operating temperature.

By the way, in conventional cooking control devices, when the sensor temperature rises to the operating temperature, the burner capacity switches from high output to low output, and when the temperature drops below the operating temperature, the burner output switches from low output to high output. It is configured to be replaced. Therefore,
During the initial start-up heating to raise the oil temperature to the appropriate temperature, as shown in Figure 4, when the temperature detected by the temperature sensor rises to the desired operating temperature, the burner capacity switches from high output to low output. However, as mentioned above, the operating temperature Tj, which is the standard for switching the heating capacity of the burner, is set higher than the appropriate oil temperature To, so there may be circumstances such as adding cold food during the heating process. The residual heat in the cooking vessel will cause the oil temperature to be significantly higher than the cooking temperature, unless
This causes what is called an overshoot.

In addition, since the temperature detected by the temperature sensor is in contact with the bottom of the cooking container, it is likely to be indirectly affected by the heat of the burner. The detection of the temperature change in the container may be delayed and the burner may not be switched from low output to high output, resulting in the oil temperature being significantly lower than the appropriate temperature.

Furthermore, the oil temperature drops rapidly when fried ingredients are added, but the subsequent temperature change between the oil and the cooking container will be affected even if the cooking container returns to its original cooking temperature, as the oil has a larger heat capacity. It takes time for the oil to return to the proper temperature. Moreover, when the temperature detected by the temperature sensor reaches the operating temperature, the burner is switched from high output to low output, which further slows down the rise in oil temperature that has not yet reached the predetermined temperature. The result will be poor quality when cooked.

<Purpose of the Invention> The present invention has been made in view of the above-mentioned problems in the prior art. The purpose is to effectively reduce temperature drops during repeated cooking.

<Structure of the Invention> In order to achieve the above-mentioned object, the cooking control device of the present invention includes a temperature sensor that detects the temperature at the bottom of the cooking container and a heating means that heats the cooking container. a temperature setting device that sets an operating temperature that is a target value for temperature control and an initial operating temperature that is lower than this operating temperature and that is a target value for temperature control during initial startup heating. Compare the detected temperature detected by the temperature sensor with the operating temperature or initial operating temperature set by the temperature setting device, and if the detected temperature is higher than the operating temperature or initial operating temperature, set the output of the means to the high output side. A comparator circuit that outputs a low output switching signal to the heat amount switching means to switch from low output to low output side, and a comparison circuit that calculates the rate of temperature decrease of the detected temperature detected by the temperature sensor, and lowers the heating means when this rate of temperature decrease is equal to or higher than a predetermined value. A temperature decreasing rate detection means is provided for outputting a high output switching signal for switching from the output side to the high output side to the heat amount switching means.

<Example> Hereinafter, an example in which the present invention is applied to a gas stove for cooking fried foods such as tempura will be described in detail.

FIG. 1 is a block diagram of a heating cooking control device. In the figure, 1 indicates the entire cooking control device, 2 is a temperature sensor that detects the temperature at the bottom of the cooking container, and 4 is a burner as a heating means for heating the cooking container. As shown in FIG. 2, the burner 4 is provided in the center of the burner 4 so as to be retractable and comes into contact with the bottom of the cooking container 6. Note that 8 is a trivet on which the cooking container 6 is placed.

Reference numeral 10 denotes a calorific value switching means for switching the output of the burner 4 between high output and low output, and is composed of, for example, electromagnetic gas valves 12a and 12b for high output and low output, which switch the gas flow rate.

14 is an operating temperature Tj that is a target value for temperature control based on the temperature detected by the temperature sensor 2, and this operating temperature Tj.
This is a temperature setting device that sets the initial operating temperature Ti, which is the target value for temperature control during initial startup heating at a lower temperature than the initial operating temperature Ti.

16 is the detected temperature Tm detected by temperature sensor 2
and the operating temperature Tj or initial operating temperature Ti set by the temperature setting device 14, and if the detected temperature Tm is higher than the operating temperature Tj or initial operating temperature Ti, the output of the burner 4 is changed from the high output side to the low output side. This is a comparator circuit that outputs a low output switching signal _S1 that switches to .

18 is the detected temperature Tm detected by temperature sensor 2
Temperature fall rate d(Tm ₂ −Tm ₁ )/dt per unit time of
(Here, Tm ₁ is the detected temperature measured last time, Tm ₂ is the detected temperature measured this time, and t is time.) If the temperature decrease rate is above a predetermined value, increase the output of burner 4 from the low output side to high. This is temperature decreasing rate detection means that outputs a high output switching signal _S2 for switching to the output side.

Reference numeral 20 denotes a signal selection circuit which selects the low output switching signal S ₁ outputted from the comparator circuit 16 and the high output switching signal S ₂ outputted from the temperature decreasing rate detection means 18 and supplies it to the heat quantity switching means 10; It consists of a circuit 22 and an RS flip-flop 24.
A one-shot circuit 26 outputs a set pulse in response to the ignition of the burner 4.

Next, the cooking temperature control operation of this cooking temperature control device will be explained with reference to the temperature characteristic diagram shown in FIG. In addition, in this example, the appropriate oil temperature To
is 180℃, and temperature control when heating oil to this temperature will be explained.

When the appropriate oil temperature is 180°C, the operating temperature Tj, which is the target value for temperature control, is set to 184°C, and the initial operating temperature Ti, which is the target value for temperature control during initial startup heating, is set to 184°C. lower temperature than that
The temperature is set at 177℃. And these operating temperatures
The respective values of Tj and initial operating temperature Ti are provided to a comparator circuit 16 by a temperature setting device 14.

In this state, when the burner 4 is ignited to heat the cooking container 6, a set pulse is output from the one-shot circuit 26, and this set pulse is input to the set terminal S of the RS flip-flop 24 of the signal selection circuit 20.
is set, and in response to this, the heat amount switching means 10 switches the output of the burner 6 to the high output side. Thus, in the initial heating state,
The burner 4 is started at high power and the cooking vessel 6 is heated.

In the initial rising heating state, the comparator circuit 16
compares the detected temperature Tm detected by the temperature sensor 2 and the initial operating temperature Ti set by the temperature setting device 14. Therefore, the detected temperature of temperature sensor 2
When Tm increases and reaches the initial operating temperature Ti, the comparator circuit 16 outputs a high-level low output switching signal _S1 , and this low output switching signal _S1
It is input to the reset terminal R of the RS flip-flop 24. As a result, RS flip-flop 2
4 is reset, in response to this, the heat quantity switching means 10 switches the output of the burner 4 from the high output side to the low output side. In this way, the cooking container 6
Since the output of the burner 4 is weakened when the residual heat of the cooking container 6 is less than that of the conventional cooking container, the temperature rise of the oil due to the residual heat of the cooking container 6 is relatively small, and overshoot can be prevented.

Since the detected temperature Tm from the temperature sensor 2 is input to the temperature decreasing rate detecting means 18, the temperature decreasing rate detecting means 18 sets the detected temperature Tm at predetermined time intervals (for example, every 5 seconds), and each time Temperature fall rate d between the measured detected temperature and the previously measured detected temperature
(Tm ₂ - Tm ₁ )/dt (here, Tm ₁ is the detected temperature measured last time, Tm ₂ is the detected temperature measured this time, t
is the time). After the output of the burner 4 is weakened, the rate of increase in oil temperature as well as the cooking vessel 6 gradually decreases, and eventually the oil temperature begins to drop. However, while the detected temperature Tm exceeds the operating temperature Tj, the output of the comparator circuit 16 is maintained at a high level even if the temperature decrease rate exceeds a predetermined value. The RS flip-flop 24 is not set and therefore the burner 4 cannot be switched to high power.

When the detected temperature Tm is lower than the operating temperature Tj and the temperature decrease rate exceeds a predetermined value, for example 1° C. in 5 seconds, the temperature decrease rate detection means 18 outputs a high level high output switching signal _S2 , This high output switching signal S ₂ is applied to one input terminal of the AND circuit 22 . At this time, since the low level output from the comparison circuit 16 is applied to the inverting input terminal of the AND circuit 22, the high output switching signal _S2 passes through the AND circuit 22 and is applied to the set terminal S of the RS flip-flop 24. is input. This results in
Since the RS flip-flop 24 is set,
In response to this, the heat quantity switching means 10 switches the output of the burner 4 from the low output side to the high output side.
In this way, when the temperature drop rate of the detected temperature Tm exceeds a predetermined value, the capacity of the burner 4 is switched from low output to high output, so the drop in oil temperature that tends to be cooled by the food being cooked is suppressed relatively early. and optimal oil temperature
The oil temperature will rise again before it drops significantly below To.

When the temperature continues to rise, the comparison circuit 16 compares the detected temperature Tm detected by the temperature sensor 2 with the temperature setting device 1.
Compare with the operating temperature Tj set in step 4. This operating temperature Tj is set higher than the initial operating temperature Ti (184°C in this example), so the burner 4
The oil temperature when the output switches from the high output side to the low output side becomes higher than when the temperature initially rises. Therefore, the cooking container 6 obtains sufficient residual heat before the output is switched, and is heated by this residual heat until the oil temperature becomes higher than that of the conventional oil. As a result, even if the oil temperature drops due to the addition of food to be cooked, the oil temperature can be maintained within the appropriate oil temperature range.

In this way, when the output of the burner 4 increases, the output of the burner 4 is switched between high and low based on the initial operating temperature Ti or the operating temperature Tj, and when the temperature decreases, the output of the burner 4 is switched between high and low based on the temperature decreasing rate. The oil temperature is maintained at approximately the appropriate temperature (180℃).

Next, switch the mode and, for example,
If the appropriate oil temperature is reset from 180°C to 160°C midway through, the operating temperature Tj will be 164°C. At this time, since the detected temperature Tm from the temperature sensor 2 has already exceeded the operating temperature Tj, the comparison circuit 16
A high-level low output switching signal _S1 is output from the output terminal 1, and the output of the burner 4 is immediately switched from the high output side to the low output side. If the detected temperature Tm is equal to or higher than the operating temperature Tj, the RS flip-flop 24 will not be set even if the temperature decrease rate exceeds 1° C. per 5 seconds, and the output of the burner 4 will not be switched to a high output. When the detected temperature Tm is lower than the operating temperature Tj and the rate of temperature decrease exceeds 1° C. per 5 seconds, the heat amount switching means 10 operates and switches from the low output side to the high output side. After that,
As mentioned above, when the temperature rises, the operating temperature Tj (164℃)
The temperature is controlled by switching the output of the burner between high and low levels based on the rate of temperature decrease when the temperature is lowered.

Although this embodiment has been described with reference to a gas stove for cooking fried foods, the present invention is not limited to this, and it goes without saying that the present invention can also be applied to other electric stoves.

<Effects of the Invention> In the present invention, the initial operating temperature, which is the reference for changing the output of the heating means in the initial state, is set to be lower than the operating temperature, which is the reference for changing the output when the temperature rises during cooking. , oil temperature overshoot during initial temperature rise is effectively suppressed. In addition, when the temperature rises during cooking, the output of the heating means is changed based on the operating temperature, and
Changes in the output of the heating means when the temperature is lowered are carried out based on the temperature lowering rate, so it is possible to reduce excessive drops in the cooking temperature due to control delays when the temperature is lowered, and also to prevent the cooking temperature from changing significantly from the appropriate temperature during repeated cooking, etc. Excellent effects such as being able to prevent a decrease in

[Brief explanation of drawings]

Figure 1 is a block diagram of the heating cooking control device, Figure 2
The figure is a configuration diagram of a burner, a temperature sensor, and a calorie switching device. Figure 3 is a temperature characteristic diagram when cooking fried food using the cooking control device of the present invention. Figure 4 is a temperature characteristic diagram when cooking fried food using a conventional cooking control device. It is a characteristic diagram. 1... Cooking control device, 2... Temperature sensor,
4... Heating means (burner), 10... Heat amount switching means, 14... Temperature setting device, 16... Comparison circuit, 18... Temperature reduction rate detection means.

Claims (1)

[Scope of Claims] 1. A temperature sensor that detects the temperature at the bottom of the cooking container; a heat amount switching device that switches the output of the heating device that heats the cooking container between high output and low output; and a target value for temperature control. a temperature setter that sets an operating temperature that is lower than the operating temperature and an initial operating temperature that is a target value for temperature control during initial startup heating at a temperature lower than the operating temperature; When the detected temperature is higher than the operating temperature or the initial operating temperature set by a comparison circuit that outputs an output to the switching means; and a high output circuit that calculates a rate of temperature decrease of the temperature detected by the temperature sensor and switches the heating means from a low output side to a high output side when the rate of temperature decrease is equal to or higher than a predetermined value. A heating cooking control device comprising: temperature decreasing rate detection means for outputting a switching signal to the heat amount switching means.