JPH06129644A - Heating cooking apparatus equipped with overheating preventive function - Google Patents

Abstract

PURPOSE:To prevent burning from being produced by tentatively judging an article to be cooked is an oily food when boiling temperature is higher than boundary temperature and thereafter, when the degree of scattering of detected temperature gets a predetermined temperature or lower, correcting the judgement result to be a moist food. CONSTITUTION:When boiling state detector means 13 judges a food to be cooked to be a boiling state, article discrimination means 11 temporarily judges the article to be an oily food when boiling temperature is higher than a boundary temperature, and discriminate the article to be a moist food as equiribrium state detector means 14 detects an equilibrium state thereafter. Interruption temperature setting means 12 sets interruption temperature based upon a result of discrimination. Judgement control means 10 compares detection temperatures by the interruption temperature setting means 12 and a temperature sensort 7 and controls a gas supply controller 4 such that a gas burner 1 is extinguished as the detection temperature rises to the interruption temperature. The interruption temperature setting means 12 sets as allowable maximum temperature first interruption temperature slightly lower than temperature where oil is fired and sets upon starting the gas burner 1 the first interruption temperature such that it gets an initial value of the interruption temperature.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention detects temperature of cooked food and regulates temperature rise of cooked food.
The present invention relates to a heating cooker with an overheat prevention function that prevents burning and ignition of cooked food.

[0002]

2. Description of the Related Art Conventionally, as a heating cooker, a temperature sensor detects the temperature of a cooking container such as a pot in which a food is put in order to prevent burning and ignition due to overheating of the food, and based on the detected temperature. A configuration has been proposed in which heating by the heating means is automatically stopped. For example, JP-A-3
In the invention described in Japanese Patent No. 236518, focusing on the fact that the change in temperature per unit time decreases when water boils, in a determination region (for example, 97 to 130 ° C.) set to detect water boiling. When the rate of change in temperature becomes equal to or lower than a predetermined value, it is determined that such a state has occurred due to boiling of water, and the cooked food is determined to be a water-cooked food with a large amount of water such as a cooked rice. In addition, when the boiling state of the cooked food is not detected in the determination area, it is determined to be an oil cooked food such as a fried food or a fried food using oil.

When it is determined to be a water-cooked product, the boiling temperature is used as the boiling temperature, and the boiling temperature is set according to the boundary temperature (for example, 108 ° C.) set to a predetermined temperature between 100 and 130 ° C. By adding a predetermined constant to the boiling temperature, the stop temperature is determined so as to prevent charring after evaporation of water. For example, when the boiling temperature is lower than the boundary temperature, 13 degrees is added, and when the boiling temperature is equal to or higher than the boundary temperature, the temperature obtained by adding 5 degrees is set as the stop temperature. Also, when it is determined that it is an oil cooked food,
Set the stop temperature to prevent ignition of oil such as tempura. The stop temperature thus determined is compared with the detected temperature, and when the detected temperature rises to the stop temperature, heating by the heating means is stopped. Further, the stop temperature, once set, is not changed during cooking.

[0004]

By the way, in this type of heating cooker, the temperature sensor is provided so as to come into contact with the outer surface of the cooking container so that the temperature sensor can be used without being aware of the position of the temperature sensor. Is normal. Therefore, the temperature difference between the inside and outside of the cooking container becomes large in a cooking container such as a thick clay pot made of a material with low thermal conductivity,
Even in the case of water-cooked food, the boiling state may not be detected in the determination area. That is, in the above conventional configuration, when the boiling temperature is detected in the determination region of 130 ° C. or less, it is determined to be water-cooked food, and when the boiling state is not detected in the determination region, it is determined to be an oil-cooked food. There is a problem that when you put water cooked food like this in a clay pot, it is misjudged as oil cooked food even if it is water cooked food. If such misjudgment occurs, the stop temperature is lower than the desired temperature. Since it will be set high, the food may be burnt.

On the other hand, when the heating means is a gas burner or the like, if the cooking vessel is temporarily separated from the heating means after it is judged to be water-cooked food and the stop temperature is set, the flame is agitated and the temperature sensor burns. There is also a problem that the detected temperature rises and exceeds the stop temperature during the period when the cooking container is apart from the heating means, and the heating means automatically stops and cooking is interrupted. Furthermore, when the cooking container is air-baked with water remaining in the cooking container, or when cooking an oil-cooked food with a high water content such as stir-fried food, the boiling state in the judgment area Since it may be detected and the stop temperature is set to a relatively low temperature corresponding to the water-cooked food, there arises a problem that the heating means is stopped during the cooking and the cooking is interrupted.

The present invention is intended to solve the above-mentioned problems, and it is possible to accurately discriminate between water-prepared food and oil-prepared food regardless of the type and shape of the cooking container, so as to prevent charring in the water-prepared food. (EN) It is intended to provide a heating cooker with an overheat prevention function, which can prevent the above-mentioned problem and also prevent the cooking from being interrupted by misidentifying an oil cooked food as a water cooked food.

[0007]

In the present invention, in order to achieve the above object, a heating means for heating a cooking container containing a food, a temperature detecting means for detecting the temperature of the cooking container,
A determination control unit that generates a stop signal when the temperature detected by the temperature detection unit rises to a set stop temperature, a heating control unit that stops heating by the heating unit when a stop signal is received from the determination control unit, and a detected temperature rise When the speed is below the default value, the boiling state detection means that determines that the cooking product is in the boiling state, and when the degree of dispersion of the detected temperature is below the default value, the heating amount by the heating means and the heat radiation amount from the cooking product and cooking container Is an equilibrium state that is almost equilibrium, and when the boiling temperature at which the boiling state is detected is lower than the predetermined boundary temperature, it is determined that the food is watery and the boiling state is detected. If there is no cooked food, it is provided with a cooked food discrimination means, and a stop temperature setting means for setting a stop temperature according to the type of cooked food discriminated by the cooked food discrimination means. Another means, when the boiling temperature is higher than the boundary temperature of the oil-oil food and temporarily determined using, is to determine the subsequent equilibrium condition is detected in the water food.

The cooked food discriminating means may be constructed so as to discriminate an oil cooked food if the temperature rise exceeds a predetermined value within a certain time after the boiling state is detected.

[0009]

According to the above construction, when the rate of rise of the detected temperature becomes equal to or lower than the predetermined value, it is determined that the cooking product is in the boiling state, and when the boiling temperature in which the boiling state is detected is lower than the predetermined boundary temperature, the moisture content is reduced. It is determined as a water-cooked food with a large amount of water, and if the boiling state is not detected, it is determined as an oil-cooked food. On the other hand, when the boiling temperature is higher than the boundary temperature, it is tentatively determined rather than presumed to be an oil-cooked product, and after the tentatively-determined that it is an oil-cooked product, when the degree of dispersion of the detected temperature becomes equal to or lower than a predetermined value, the heating means It is determined that the amount of heat generated by the heat treatment and the amount of heat radiated from the cooked food and the cooking container are substantially in equilibrium, and at this time, the determination result is corrected to the water cooked food. In this way, if the equilibrium state is detected even after once discriminating from oil-cooked foods, the discrimination result can be corrected to water-cooked foods.In order to prevent oil ignition, the stop temperature is set high first to ensure safety. However, when it is determined that the food is water-cooked in a cooking container whose outer surface temperature is high, such as a clay pot, the stop temperature can be lowered to prevent burning.

In addition, if the temperature rise within a certain period of time after the water cooking product is judged to be a predetermined value or more, it is judged that it is an oil cooking product. If the cooking container is temporarily separated and the detected temperature rises, or if water evaporates and the detected temperature rises after detecting the boiling state like stir-fried food, the type of cooked food is corrected to oil cooked food. It is possible to prevent the heating means from stopping during cooking by raising the stop temperature.

[0011]

FIG. 2 shows a schematic configuration of an embodiment of the present invention. A gas burner 1 is used as the heating means, and in the combustion gas supply path 2 to the gas burner 1, a main valve 3 for manually opening and closing the flow path and adjusting the flow rate of the combustion gas,
A gas supply control device 4 as a heating control means including an electromagnetic valve and the like is provided. The main valve 3 is provided with a knob (not shown) for manual operation, and the ignition / extinction and the flow rate of the combustion gas are adjusted by operating the knob. The knob for ignition / extinction of the main valve 3 and the knob for adjusting the flow rate may be provided separately. Further, the flow rate of the combustion gas may be adjusted by the gas supply control device 4 so that the main valve 3 and the gas supply control device 4 work together.

At the central portion of the upper surface of the gas burner 1, the temperature of the outer lower surface of the cooking container 6 is detected by contacting the central portion of the lower surface of the cooking container 6 placed on the Gotoku 5 arranged around the gas burner 1. A temperature sensor 7 such as a thermistor is provided as a temperature detecting means. The temperature detection signal output from the temperature sensor 7 is input to the control device 8. The temperature sensor 7 is urged by a spring or the like so as to be able to come into contact with any shape of cooking container 6 such as a deep pot such as a soup pot, a flat pot such as a frying pan, and a medicine can. The control device 8 controls the gas supply control device 4 based on the temperature detection signal from the temperature sensor 7, and generates a stop signal for stopping heating by the gas burner 1 so as to prevent overheating of the cooking container 6. As a result, the gas supply control device 4 is driven to shut off the combustion gas supply path.

As shown in FIG. 1, the control unit 8 determines whether the type of food to be cooked is a water-rich food such as boiled rice, a fried food or a fried food, based on the temperature detected by the temperature sensor 7. It is provided with cooked food discrimination means 11 for discriminating whether it is an oil cooked food using oil, and stop temperature setting means 12 for setting a stop temperature based on the discrimination result by the cooked food discrimination means 11. Further, in the judgment control means 10, the stop temperature setting means 1
The stop temperature set in 2 is compared with the temperature detected by the temperature sensor 7. When the detected temperature rises to the stop temperature, a stop signal is output so as to extinguish the gas burner 1, and the gas supply control device 4 is controlled. Here, in the stop temperature setting means 12, a first stop temperature (for example, 250 ° C.) which is slightly lower than the temperature at which oil ignites is set as the maximum allowable temperature, and when the gas burner 1 is started, the first stop temperature is the initial stop temperature. It is set to be a value.

The cooked food discriminating means 11 detects the boiling state of the cooked food contained in the cooking container 6 based on the variation pattern of the temperature detected by the temperature sensor 7.
And an equilibrium state detecting means 14 for detecting an equilibrium state in which the heating amount by the gas burner 1 and the heat radiation amount from the cooked food and the cooking container 6 are almost in equilibrium based on the variation pattern of the detected temperature.
The type of cooked food is determined based on the detection result of.
The boiling state detecting means 13 can determine the boiling temperature which is the temperature when the boiling state is detected, and the equilibrium state detecting means 14 can determine the equilibrium temperature which is the temperature when the equilibrium state is detected. The cooked food discrimination means 11 discriminates between water cooked food and oil cooked food in the following manner. As shown in FIG. 3, when the heating by the gas burner 1 is started, the stop temperature is set to the first stop temperature on the assumption of the oil-cooked product as the initial state (S1). When the detected temperature rises to the lower limit temperature of the determination region set across the boiling point of water (S2), it is determined based on the detected temperature whether or not the cooking product is in the boiling state, based on the detection result of the boiling state detection means 13 ( S3).

The boiling state detection means 13 determines the boiling state as follows. First, in the judgment area, the reference temperature area is set to a constant temperature range in which the temperature is lower than the boiling point of water, and the time required for the detected temperature to pass through the reference temperature area is determined. Set the reference time by multiplying by the constant. After the detected temperature exceeds the reference temperature region, if the time required for the detected temperature to rise to the predetermined constant temperature becomes longer than the reference time, it is determined that the boiling state is reached. After all, it is considered that the boiling state is reached when the rising rate of the detected temperature becomes small. The determination of the boiling state is continuously performed until the lower determination temperature (for example, 160 ° C.) that is set lower than the first stop temperature and higher than the upper limit temperature of the determination region (S6), and the detected temperature exceeds the lower determination temperature. Even if boiling is not detected, it is determined to be an oil-cooked food (S7). When the boiling state is detected, the temperature at that time is set as the boiling temperature (S4), and the stop temperature is slightly lowered to the second stop temperature (for example, 190 ° C.) (S5).

When the boiling state is detected, the equilibrium state detecting means 14 determines whether or not there is an equilibrium state in which the heating amount by the gas burner 1 and the heat radiation amount from the cooked substance are in equilibrium (S
9, S12), the equilibrium temperature is determined when the equilibrium state is reached (S13). Here, as described later, the boiling temperature is compared with the boundary temperature set at a temperature lower than the upper limit temperature of the determination region by a constant temperature (for example, 10 ° C.) and higher than the boiling point of water (S8), and the boiling temperature is determined. The stop temperature is classified based on the level relationship between the boundary temperature and the boundary temperature.

The determination of the equilibrium state is performed as follows. First,
The detected temperature is sampled at a constant cycle (several tens of seconds), and a predetermined number (several) of time series of sampled values are set.
The last sampled value of each set is shared with the first sampled value of the next set arranged in time series. Also, with the first sampling value of each set as the reference value, the specified number of sampling values within the same set (most of the number of sampling values in each set) is within the specified temperature range for the reference value. When it is within a few degrees above and below, the group is regarded as a passing group. The above-described determinations are sequentially performed for each pair, and when two pairs arranged in time series are consecutively acceptable pairs, the equilibrium state is determined. After all, it is considered that the equilibrium state is reached when the dispersion of the sampling values becomes small. For the equilibrium temperature, the first sampled value of the passing set is used. After the boiling state is detected, the equilibrium state is continuously determined until the lower determination temperature (S10, S17).

The cooked product discriminating means 11 discriminates the cooked food according to the combination of the boiling temperature and the equilibrium temperature as follows, and the stop temperature setting means 12 sets the stop temperature as follows. That is, when the boiling temperature is lower than the boundary temperature, it is temporarily determined to be a water-cooked food, and if the equilibrium state is not detected thereafter, the stop temperature is maintained at the second stop temperature (S1).
1). On the other hand, when the boiling temperature is higher than the boundary temperature, it is tentatively discriminated as an oil-cooked food, and if the equilibrium state is not detected thereafter, the cooked food is confirmed as an oil-cooked food and stopped when the detected temperature exceeds the lower determination temperature. Set the temperature to the first stop temperature (S1
8). In addition, if the equilibrium state is detected after the boiling state is detected, it is determined as water-cooked food, and if the equilibrium temperature is in the range above the upper limit temperature of the discrimination region and lower than the lower discrimination temperature, the equilibrium temperature is a constant temperature. The third stop temperature obtained by adding (for example, 30 ° C.) is set as the stop temperature (S15), and when the equilibrium temperature is lower than the upper limit temperature of the determination region, the fourth stop temperature is higher than the upper limit temperature by a constant temperature (for example, 10 ° C.). Is set as the stop temperature (S16). That is, regardless of the relationship between the boiling temperature and the boundary temperature, when the equilibrium state is detected after the boiling state is detected, the determination result as a water cooking product is obtained even if it is provisionally determined as an oil cooking product before that. Correct it. In this way, the oil cooking or the water cooking is determined based on the boiling temperature and the equilibrium temperature. In the oil cooking, the stop temperature becomes the first stop temperature, and in the water cooking, the stop temperature becomes the third stop. Temperature or the fourth stop temperature. Further, the third stop temperature becomes the stop temperature when the equilibrium temperature is higher than the upper limit temperature of the determination region. Therefore, generally, the third stop temperature is set when the thickness of the cooking container 6 is large. become. The second stop temperature is set when it is not possible to determine whether the food is oil or water.

By the way, when the cooking container 6 with water remaining is air-baked or fried, the detected temperature rises without detecting the equilibrium state after the boiling state is once detected. Therefore, when the boiling temperature is tentatively determined to be a water-cooked food at the boundary temperature or lower (S11), the detected temperature rises within a certain time (for example, 30 seconds) from the detection of the boiling state,
When the rising temperature exceeds a predetermined value (for example, 5 ° C) (S1
9), the determination result is corrected to the oil cooking product, and the stop temperature is set to the first stop temperature (S20).

The stop temperature is set in the above-described procedure, and when the detected temperature becomes equal to or higher than the stop temperature (S2
1), extinguish the gas burner 1 immediately (S22). At the same time that the gas burner 1 is extinguished, a buzzer or a lamp notifies the extinguishing (S23). In this way, it is possible to reduce the burning of water-cooked foods and prevent the ignition of oil-cooked foods.

The control device 8 is basically composed of a microcomputer, and uses an analog-digital converter for converting the temperature detection signal of the temperature sensor 7 into digital data or a gas according to the judgment result of the judgment control means 10. A drive circuit for driving the supply control means 4 and the like are provided. As described above, even if the boiling state is detected by the rising speed of the detected temperature, if the boiling temperature exceeds the boundary temperature, the equilibrium state is determined based on the degree of dispersion of the detected temperature, and when the equilibrium state is detected. Since it is determined to be a water-cooked food, even if the cooking container 6 having a low heat transfer coefficient and a large thickness, such as a clay pot, is used, the water-cooked food can be discriminated without error. Can be prevented. On the other hand, even if the boiling state is equal to or lower than the boundary temperature, if the temperature rise within a certain period of time after detection of the boiling state is equal to or higher than a predetermined value, it is determined to be an oil-cooked product, and therefore the cooking container 6 with water remaining is bake. In the case of cooked foods such as stir-fried foods where water comes out, even if the boiling state is detected and it is once distinguished as water cooked food, the determination result is corrected immediately as oil cooked food,
The fire extinguishing of the gas burner 1 during cooking can be prevented.

In addition to the gas burner 1, a heater, an electromagnetic cooker or the like may be used as the heating means, and a thermistor which comes into contact with the bottom of the cooking container 6 containing the food to be used is used as the temperature detecting means. What detects the temperature of the cooking container 6 from the outside of the container 6 by the amount of infrared rays or the like may be used.

[0023]

As described above, according to the present invention, when the boiling temperature is higher than the boundary temperature, it is tentatively determined rather than presumed to be an oil-cooked product, and after tentatively determined to be an oil-cooked product, the detected temperature When the degree of dispersion becomes less than the default value, it is determined that the amount of heat from the heating means and the amount of heat radiated from the food and cooking container are in an almost equilibrium state, and when the equilibrium state is detected, the determination result is corrected to water-cooked food. Therefore, if the equilibrium state is detected even after once distinguishing it from oil-cooked food, it can be corrected to a water-cooked food.In order to prevent oil ignition, the stop temperature is set high first to ensure safety. However, when it is determined that the food is water-cooked in a cooking container whose outer surface has a high temperature like a clay pot, the stop temperature can be lowered to prevent burning.

In addition, if the temperature rise within a certain period of time after it is determined to be a water-cooked product is determined to be an oil-cooked product, it is determined to be a water-cooked product and the stop temperature is set, and then the heating means is used. If the detection temperature rises by temporarily separating the cooking container, or if the boiling temperature is detected once the boiling state is once detected, such as when the food is air-baked with water remaining in the cooking container, if the detection temperature rises, There is an advantage that it is possible to prevent the heating means from stopping during cooking by correcting the type of food to be oil-cooked and raising the stop temperature.

[Brief description of drawings]

FIG. 1 is a block diagram showing an embodiment.

FIG. 2 is a schematic diagram showing the overall configuration of the embodiment.

FIG. 3 is a flowchart illustrating the operation of the embodiment.

[Explanation of symbols]

 1 Gas Burner 2 Gas Supply Channel 3 Main Valve 4 Gas Supply Control Device 5 Gokutoku 6 Cooking Container 7 Temperature Sensor 8 Control Device 10 Judgment Control Means 11 Cooked Food Discrimination Means 12 Stop Temperature Setting Means 14 Boiling State Detection Means 14 Equilibrium State Detection Means

Front page continuation (72) Inventor Yukiko Tani 1-152 Oka Minami-shi Minato-ku Osaka City Harman Co., Ltd.

Claims (2)

[Claims] 1. A heating means for heating a cooking container containing a food, a temperature detecting means for detecting the temperature of the cooking container, and a stop signal generated when the temperature detected by the temperature detecting means reaches a set stop temperature. Determination control means, a heating control means for stopping heating by the heating means when a stop signal is received from the determination control means, and a boiling state in which the cooked product is determined to be in a boiling state when the rate of increase in the detected temperature is equal to or lower than a predetermined value. The detecting means, an equilibrium state detecting means for determining that the amount of heat generated by the heating means and the amount of heat radiated from the cooking object and the cooking container are in an almost equilibrium state when the degree of dispersion of the detected temperature is equal to or less than a predetermined value, and a boiling state. When the detected boiling temperature is lower than the predetermined boundary temperature, it is judged as water-rich food,
If the boiling state is not detected, it includes a cooking product discrimination means for discriminating it as an oil cooking food, and a stop temperature setting means for setting a stop temperature according to the type of the cooking food discriminated by the cooking food discrimination means. When the boiling temperature is higher than the above-mentioned boundary temperature, the discrimination means temporarily discriminates that it is an oil-cooked food using oil, and if an equilibrium state is subsequently detected, it discriminates it as a water-cooked food. Heating cooker. 2. The overheat prevention function according to claim 1, wherein the cooked food discriminating means discriminates that the cooked food is an oil cooked food when the temperature rise exceeds a predetermined value within a certain time after the boiling state is detected. Heating cooker.