JP2664608B2 - Heating cooker with overheating prevention function - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a heating cooker having an overheat prevention function for detecting a fluctuation pattern of the temperature of a cooked product and restricting a rise in the temperature of the cooked product, thereby preventing burning and ignition of the cooked product. Things.

[0002]

2. Description of the Related Art Conventionally, a heating cooker such as a gas stove has been provided which automatically adjusts the heating power of a gas burner, which is a heating means, in accordance with the type of food to be cooked. The type of the food is estimated based on a fluctuation pattern of the temperature of the food detected by the temperature sensor as the temperature detecting means. That is, the temperature sensor detects the temperature of the outer surface of the bottom of the cooking container such as a pot containing the food,
On the basis of the fluctuation pattern of the detected temperature, it is determined whether the cooked food is rich in water, such as boiled cooked food, or the cooked oil that uses oil such as fried food or fried food.

[0003] Further, when it is determined that the food is water cooked, the gas burner is automatically extinguished when the detected temperature rises to a predetermined stop temperature in order to prevent the water from being scorched when the water evaporates. When it is determined that the gas temperature is higher than the stop temperature, the gas burner can be automatically extinguished in order to prevent the oil from igniting. By automatically extinguishing the gas burner in this way, scorching of the food and occurrence of a fire are prevented.

[0004]

By the way, in the case of stewed or stir-fried foods, it is possible to perform operations such as shaking the cooking container on the gotoku or lifting the cooking container from the gotoku.
When the cooking vessel is operated in this manner, the flame of the gas burner is blown and the flame is directly applied to the temperature sensor, so that the temperature detected by the temperature sensor rapidly rises. In the heating cooker described above, the stop temperature for water cooked food is set by focusing on the fact that the detected temperature rises sharply when water cooked starts to burn, and it is stopped to prevent oil ignition for oil cooked food. The temperature is set, and in any case, when the detected temperature rises rapidly and reaches the stop temperature, the gas burner is automatically extinguished. That is, when the cooking container is operated as described above, there is a problem that the gas burner extinguishes during the cooking and the cooking is interrupted.

In addition, as a method of automatically determining the type of food, attention is paid to the fact that a water cooking product is brought into a boiling state when heating is continued and the temperature is kept substantially constant.
When the temperature does not reach the predetermined determination temperature, it is determined that the food is water cooking, and when the temperature exceeds the determination temperature, it is determined that the food is oil cooking. In such a case, there is a problem that the food is erroneously determined to be an oil-cooked food despite being a water-cooked food. That is, the temperature at which the temperature at which the water food is prevented from burning is set as the stop temperature, and the temperature at which the food is determined to be oil cooking and the ignition is prevented may be set as the stop temperature. Since the temperature is usually higher than the temperature for preventing scorching, there arises a problem that the cooked product is scorched.

SUMMARY OF THE INVENTION An object of the present invention is to solve the above-mentioned problem. When an operation for shaking or floating a cooking vessel is performed, the timing for stopping the heating means is shorter than when no operation is performed. It is an object of the present invention to provide a heating cooker with an overheating prevention function that prevents interruption of cooking by delaying the cooking and prevents the water cooked product from being scorched when the stop temperature is automatically set.

[0007]

According to the first aspect of the present invention, in order to achieve the above object, a heating means for heating a cooking container for storing food, a temperature detecting means for detecting a temperature of the food, Determination control means for generating a stop signal when the temperature detected by the detection means rises to the set stop temperature,
Heating control means for stopping the heating by the heating means upon receiving a stop signal from the determination control means; change rate detection means for obtaining a temperature increase per unit time for the temperature detected by the temperature detection means; and detection obtained by the change rate detection means. Operation detecting means for determining that an operation has been performed on the cooking vessel when the state in which the temperature rise per predetermined time is equal to or higher than a predetermined value continues for a predetermined time or more, and operation of the cooking vessel is detected by the operation detecting means Then, a stop control means for delaying the stop timing of the heating means is provided.

According to the second aspect of the present invention, the heating means for heating the cooking container for storing the food, the temperature detecting means for detecting the temperature of the food, and the temperature detected by the temperature detecting means when the temperature rises to the set stop temperature. Determination control means for generating a stop signal, heating control means for stopping heating by the heating means upon receipt of the stop signal from the determination control means, and a change for obtaining a rise time required for the temperature detected by the temperature detection means to rise by a certain temperature. Rate detecting means, operation detecting means for determining that an operation has been applied to the cooking container when a state in which the rise time obtained by the change rate detecting means is equal to or less than a predetermined value is obtained a plurality of times in succession, Stop control means for delaying the stop timing of the heating means when the operation of the cooking vessel is detected by the detection means is provided.

[0009]

According to the structure of the first aspect, the temperature rise per predetermined time is obtained, and when the state where the temperature rise is equal to or higher than the predetermined value continues for the predetermined time or longer, it is determined that the cooking vessel is operated, Since the stop timing of the heating means is delayed when the cooking vessel is operated, the cooking vessel is operated even if the temperature detected by the temperature detecting means is increased by shaking or floating the cooking vessel. If the temperature rises as a result, it is possible to prevent the heating means from being stopped during the cooking, thereby preventing the interruption of the cooking. As a method of delaying the stop timing of the heating means, the stop temperature set at the time when the operation of the cooking vessel is detected is raised, or the determination of the heating stop is prohibited while the temperature is rising due to the operation of the cooking vessel, and the detection temperature is prohibited. May be determined after the temperature has once decreased and then increased.

Further, when the stop temperature is automatically set by discriminating between the water-cooked food and the oil-cooked food, erroneous determination of the cooked food can be prevented, and the water-cooked food is mistaken for the oil-cooked food. In addition, it is possible to prevent burning and prevent the cooking means from being erroneously discriminated from the oil-cooked food as a water-cooked food, and to automatically stop the heating means during the cooking.

According to a second aspect of the present invention, a rising time required for the temperature detected by the temperature detecting means to rise by a predetermined temperature is obtained, and a state in which the rising time is equal to or less than a predetermined value is obtained a plurality of times in succession. In this case, even if the stop timing of the heating means is delayed, the operation is performed in the same manner as in claim 1.

[0012]

【Example】

Embodiment 1 FIG. 2 shows a schematic configuration of an embodiment of the present invention.
In this embodiment, the case where the stop temperature of the heating means is automatically set is described. However, the technical idea of the present invention is applicable regardless of the method of setting the stop temperature. A gas burner 1 is used as a heating means, and a main passage 3 for opening and closing the flow passage and adjusting a flow rate of the combustion gas by a manual operation are provided in a supply path 2 for the combustion gas to the gas burner 1, and an electromagnetic valve and the like. A gas supply control device 4 as heating control means is provided. The main valve 3 is provided with a knob (not shown) for manual operation, and operates the knob to control ignition / extinguishing and flow rate of the combustion gas. The ignition / extinguishing knob 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 are linked.

At the center 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 center of the lower surface of the cooking container 6 placed on the goto 5 disposed 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 contact any shape of the cooking vessel 6 such as a soup pot, a deep pot such as a frying pan, a pot, etc. 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 the heating by the gas burner 1 so as to prevent the cooking vessel 6 from overheating. Thus, the gas supply control device 4 is driven to cut off the supply path of the combustion gas.

As shown in FIG. 1, the controller 8 determines whether the type of food is a water-cooked food such as boiled food or a fried food or stir-fry based on the temperature detected by the temperature sensor 7. The apparatus includes a cooking object discriminating unit 11 for discriminating an oil cooking product using oil, and a stop temperature setting unit 12 for setting a stop temperature based on a result of the discrimination by the cooking object discriminating unit 11. In the determination control means 10, the stop temperature setting means 1
The stop temperature set in Step 2 is compared with the temperature detected by the temperature sensor 7, and 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, the stop temperature setting means 12 sets a first stop temperature (for example, 250 ° C.) slightly lower than the temperature at which oil ignites as the allowable maximum temperature, and when the gas burner 1 is started, the first stop temperature is set to the initial stop temperature. It is set to be a value.

In the cooked food discriminating means 11, the water cooked food and the oil cooked food can be automatically determined based on the temperature detected by the temperature sensor 7. Since the detected temperature is considerably high, and the change tendency of the detected temperature is completely different from that of the water-cooked food or the oil-cooked food, the baked food is set by the mode selection switch SW without performing the automatic determination based on the detected temperature. ing. That is, the mode selection switch SW has an automatic mode for automatically distinguishing between water-cooked food and oil-cooked food;
It is possible to select one of the grilling modes to be selected for grilling. Further, a temperature setting unit (not shown) for setting a heating temperature of the gas burner 1 in the cooking device.
It is preferable to provide a display unit (not shown) for displaying the mode selected by the mode selection switch SW or the like.

The control device 8 further includes a change rate detecting means 13 for obtaining a temperature rise per unit time of the temperature detected by the temperature sensor 7, and a temperature increase per unit time of the detected temperature obtained by the change rate detector 13. And operation detecting means 14 for determining that an operation such as shaking or lifting the cooking container 6 has been performed when the state in which. Further, when the operation of the cooking vessel 6 is detected by the operation detecting means 14, the stop temperature of the stop temperature setting means 12 is corrected so that the stop timing of the gas burner 1 is delayed, or the detected temperature once drops and then rises again. The stop control means 15 for prohibiting the stop of the gas burner 1 until the operation is performed is provided.

The cooking item discriminating means 11 discriminates between a water cooking item and an oil cooking item as follows. As shown in FIG.
At the time when the heating by the gas burner 1 is started, the stop temperature is set to the first stop temperature, assuming the oil cooking as an initial state (S1). When the detected temperature rises to the lower limit temperature of the determination region set with the boiling point of water in between (S2), it is determined whether or not the food is boiling based on the detected temperature (S3).

The determination of the boiling state is performed as follows. First, the reference temperature range is set to a constant temperature range in a temperature range lower than the boiling point of water in the determination range, and the time required for the detected temperature to pass through the reference temperature range is determined. Set the reference time by multiplying by the constant. After the detected temperature exceeds the reference temperature range, if the time required for the detected temperature to rise by a predetermined constant temperature becomes longer than the reference time, it is determined that a boiling state has occurred. Eventually, when the rate of rise of the detected temperature decreases, it is considered that a boiling state has occurred. The determination of the boiling state is continuously performed up to the lower determination temperature (for example, 160 ° C.) 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 that the food is an oil cooked food (S7). If the boiling state is detected, the temperature at that point 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, it is determined whether or not the amount of heating by the gas burner 1 and the amount of heat radiated from the cooking material are in an equilibrium state (S9, S12). Is determined (S13). Here, as described later, the boiling temperature is compared with a boundary temperature set at a temperature lower than the upper limit temperature of the determination region by a certain temperature (for example, 10 ° C.) and higher than the boiling point of water (S8).
The stop temperature is classified based on the relationship between the boiling temperature and the boundary temperature.

The determination of the equilibrium state is performed as follows. First,
The detected temperature is sampled at a constant period (several tens of seconds), and a time series of sampling values is grouped by a predetermined number (several).
The last sampled value of each set is shared with the first sampled value of the next set in chronological order. In addition, the specified number of sampling values in the same set (most of the number of sampled values in each set) is within a specified temperature range (several degrees above and below) with the first sampling value of each set as a reference value. , The group is regarded as a passing group. The above-described determination is performed for each set in order, and when two sets arranged in chronological order are successively passed sets, it is determined that an equilibrium state has been reached. Eventually, when the degree of dispersion of the sampling values decreases, it is considered that an equilibrium state has been reached. For the equilibrium temperature, the first sampling value of the passing set is used. After the boiling state is detected, the determination of the equilibrium state is continuously performed up to the lower determination temperature (S10, S17).

By the way, the food discriminating means 11 discriminates the food according to the combination of the boiling temperature and the equilibrium temperature as follows, and the stop temperature by the stop temperature setting means 12 is set as follows. That is, when the boiling temperature is lower than the boundary temperature, it is tentatively determined that the food is a water cooked food, and if no equilibrium state is detected thereafter, the stop temperature is maintained at the second stop temperature (S11). On the other hand, when the boiling temperature is higher than the boundary temperature, the food is temporarily determined to be an oil cooked food, and if no equilibrium state is detected thereafter, the cooked food is determined to be an oil cooked food and stopped when the detected temperature exceeds the lower determination temperature. The temperature is set to the first stop temperature (S18). In addition, if the equilibrium state is detected after the boiling state is detected, it is determined that the food is water-cooked food. The third stop temperature to which (for example, 30 ° C.) is added 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 that is higher than the upper limit temperature by a certain temperature (for example, 10 ° C.). Is the stop temperature (S16). In other words, regardless of the relationship between the boiling temperature and the boundary temperature, if the equilibrium state is detected after the detection of the boiling state, the result of the determination as a water-cooked food is obtained even if it is provisionally determined earlier to be an oil-cooked food. Correct it. In this way, it is determined based on the boiling temperature and the equilibrium temperature whether the product is an oil cooked product or a water cooked product. The stop temperature of the oil cooked product is the first stop temperature, and the stop temperature of the water cooked product is the third stop temperature. Temperature or the fourth stop temperature. Since the third stop temperature becomes the stop temperature when the equilibrium temperature is higher than the upper limit temperature of the determination region, the third stop temperature is generally set when the thickness of the cooking container 6 is large. become. 2nd when it is not possible to decide whether to cook oil or water
The stop temperature is set.

The stop temperature is set according to the procedure described above. If the operation of the cooking vessel 6 is not detected by the operation detecting means 14 as shown in FIG. 4 (S19), the detected temperature is stopped. When the temperature becomes equal to or higher than (S24), the gas burner 1 is immediately extinguished (S25). Gas burner 1
At the same time as the fire extinguishing, the fire extinguishing is notified by a buzzer or a lamp (S26). In this way, it is possible to reduce the sticking of the cooked water product and prevent the ignition of the cooked oil product.

On the other hand, when the change rate detecting means 13 detects a sharp rise in the detected temperature, the operation detecting means 14 determines that an operation has been applied to the cooking vessel 6. That is, the change rate detecting means 13 measures the rising time at predetermined temperature intervals (several degrees) from the lower limit temperature of the determination region, and the operation detecting means 14 determines that the state where the rising time is within the predetermined time (several seconds) is the predetermined number of times. If they continue, it is determined that the cooking container 6 has been shaken or floated (S19). In this way, when the operation of the cooking vessel 6 is detected, the stop control unit 15 stops the detection temperature even when the detected temperature reaches the stop temperature (S21).
It is prohibited to extinguish the gas burner 1 for a fixed time (for example, 10 seconds) (S22, S23), and after the fixed time has elapsed, only when the detected temperature exceeds the stop temperature (S24), the gas burner 1 is extinguished. (S25). Here, when the operation of the cooking vessel 6 is detected, the extinguishing timing of the gas burner 1 can be delayed even if the stop temperature is raised by a certain temperature.

On the other hand, a certain time (for example, 15 seconds) is timed after the operation of the cooking vessel 6 is detected (S2).
0), if the detected temperature does not drop and the stop temperature has not been reached during the fixed time (S21, S27), the stop control means 15 is reset after the time limit ends (S28). That is, when the detected temperature reaches the stop temperature after the end of the time limit, the gas burner 1 is extinguished immediately. By performing such a process, even when a small amount of oil is being heated, even if the detection temperature rises rapidly and the cooking container 6 is erroneously determined to be operating, the detected temperature will be the stop temperature. Otherwise, the operation returns to the normal operation after the end of the time limit. That is, ignition of oil can be prevented. In this case, there is no problem because there is no change in the stop timing.

Further, when the cooking container 6 is placed on the gorge 5 after the operation of the cooking container 6 is detected, the detected temperature decreases. Therefore, when the detected temperature falls below the stop temperature, the stop control means 15 is reset. (S29, S30) Then, when the detected temperature reaches the stop temperature, the gas burner 1 is extinguished immediately. If the stop control means 15 is reset in this way, the function of preventing scorching of the cooked water and ignition of oil does not occur.

When the water-cooked food is boiled down, the detected temperature rises rapidly. However, the rate of temperature rise when the water-cooked food boils down is slower than that when the cooking vessel 6 is operated. Therefore, by appropriately selecting the threshold value of the rising rate for judging the operation of the cooking vessel 6, the two can be distinguished, and the gas burner 1 for preventing scorching of the water-cooked food can be obtained.
Fire extinguishing timing is not delayed.

The above-mentioned control device 8 is basically constituted by a microcomputer, and an analog-to-digital converter for converting a temperature detection signal of the temperature sensor 7 into digital data, and a judgment result by the judgment control means 10. A driving circuit for driving the gas supply control means 4 is provided. The heating means may use a heater or an electromagnetic cooker in addition to the gas burner 1, and the temperature detecting means may include
In addition to using a thermistor in contact with the bottom of the cooking container 6 containing the food, a device that detects the temperature of the cooking container 6 from the outside of the cooking container 6 based on the amount of infrared rays or the like may be used.

[0028]

According to the present invention, as described above, it is determined that the cooking vessel is being operated when the temperature rising rate is equal to or more than the predetermined value, and the cooking vessel is operated. When the temperature of the cooking container is being operated, the stop timing of the heating means is delayed, so that even if the temperature detected by the temperature detecting means is increased by shaking or floating the cooking container, the temperature rise due to the operation of the cooking container. If there is, there is an advantage that the stop of the heating means during the cooking can be prevented and the interruption of the cooking can be prevented.

Further, when the stop temperature is automatically set by discriminating between the water-cooked food and the oil-cooked food, erroneous determination of the cooked food can be prevented, and the water-cooked food is mistaken for the oil-cooked food. There is an advantage that it is possible to prevent burning and prevent the cooking means from being separated and prevent the heating means from being automatically stopped during cooking due to erroneous determination of the oil cooked food as the water cooked food.

[Brief description of the drawings]

FIG. 1 is a block diagram showing an embodiment.

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

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

FIG. 4 is a flowchart illustrating the operation of the embodiment.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Gas burner 2 Gas supply path 3 Main valve 4 Gas supply control device 5 Gotoku 6 Cooking vessel 7 Temperature sensor 8 Control device 10 Judgment control means 11 Cooking discrimination means 12 Stop temperature setting means 13 Change rate detection means 14 Operation detection means 15 Stop Control means

 ──────────────────────────────────────────────────続 き Continued on the front page (72) Inventor Yutaka Yoshida 1-1-52, Oka, Minami-shi, Minato-ku, Osaka-shi Harman Co., Ltd. (56) References JP-A-3-195824 (JP, A) JP-A-4 −313620 (JP, A)

Claims (2)

(57) [Claims] 1. A heating means for heating a cooking container for storing food, a temperature detecting means for detecting a temperature of the food, and a stop signal is generated when the temperature detected by the temperature detecting means rises to a set stop temperature. Determination control means, heating control means for stopping heating by the heating means when a stop signal is received from the determination control means, change rate detection means for obtaining a rise in temperature per unit time with respect to the temperature detected by the temperature detection means, and change rate detection Operation detecting means for determining that an operation has been applied to the cooking container when a state in which the temperature increase per unit time of the detected temperature obtained by the means is equal to or higher than a predetermined value continues for a predetermined time or more; Heating cooking with an overheating prevention function, comprising: stop control means for delaying the stop timing of the heating means when the operation of the container is detected. vessel. 2. A heating means for heating a cooking container in which food is stored, a temperature detecting means for detecting a temperature of the food, and a stop signal is generated when the temperature detected by the temperature detecting means rises to a set stop temperature. Determination control means, a heating control means for stopping the heating by the heating means when receiving a stop signal from the determination control means, a change rate detection means for determining a rise time required for the temperature detected by the temperature detection means to rise by a certain temperature, Operation detection means for determining that an operation has been applied to the cooking container when a state in which the rising time obtained by the change rate detection means is equal to or less than a predetermined value is obtained continuously plural times,
A heating cooker with an overheating prevention function, comprising: stop control means for delaying the stop timing of the heating means when the operation of the cooking vessel is detected by the operation detection means.