JP3031369B1 - Cooking device - Google Patents

Abstract

Abstract: PROBLEM TO BE SOLVED: To improve the accuracy of temperature measurement in a heating cooker, the configuration of a measurement circuit becomes complicated and the measurement speed is reduced. SOLUTION: An input to a control circuit 2 of a temperature detecting means is:
This is performed using the analog-to-digital conversion input of the microcomputer constituting the control circuit 2, and the analog-to-digital conversion input of the microcomputer is changed according to the state of the temperature input of the temperature detecting means or the state of the control means for adjusting the heating power of the heating means. A cooking device that changes the measurement accuracy.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a cooking device using an analog-to-digital conversion input (hereinafter referred to as an AD input) of a microcomputer.

[0002]

2. Description of the Related Art FIG. 8 is a block diagram showing the structure of a conventional general cooking device. 8, reference numeral 1 denotes a heater for heating a load, and reference numeral 2 denotes a control circuit for turning on / off the heater 1. This control circuit includes a heater 1 for the commercial AC power supply.
And a microcomputer 2b for outputting a signal to the drive circuit 2a. The microcomputer is 8 bi.
An AD conversion input terminal having a measurement accuracy of t is provided. 2
c is a temperature detection circuit, which is composed of resistors R2 to R6 and the like. Reference numeral 3 denotes a thermistor of a temperature sensor for detecting the temperature of the load.

The operation of temperature detection by this configuration will be described with reference to FIG. 8 and FIG. R6 is a resistance for detecting disconnection of the thermistor 3, and is 1.7 MΩ. R3-R5
Is a resistance value in accordance with the temperature range to be measured. For example, when the temperature to be measured is 200 ° C., if the thermistor is 875Ω at 200 ° C., the resistance value is set to 910Ω and the AD input of the microcomputer 2b is set. , A voltage that is about の of the reference voltage for AD conversion is input, and the change temperature per digit can be measured most accurately.

For example, when R3 is set to 910Ω,
At around 200 ° C., only SW1 in the microcomputer is connected to GND for measurement. At this time, the data inputted to the AD conversion input terminal is 8 bits, that is, 130 digits of the resolution of 255 steps. And the measurement accuracy is about 0.6 ° C./digit, that is, 131
Digit is about 200.6 ° C.

The same applies to the other resistance values of R4 and R5.
For example, to detect the boiling of water, the best measurement accuracy is obtained at 100 ° C., the boiling is detected, additional water is detected and the water is re-boiled, or the sudden rise in temperature is detected and the food is cooked. It is something that detects burning. Further, in an automatic bread baker or an oven with a fermentation function, the most accurate control is performed at around 40 ° C. to control the fermentation of the dough.

[0006]

However, in the configuration of the conventional heating cooker shown in FIG. 7 as described above, the first problem is that switching resistances are required by the number of temperature points of the specifications required for the product. . In addition, there is a problem that the measurement speed is reduced when performing AD conversion having a resolution of 10 bits in order to increase the accuracy in any measurement range. Therefore, there has been a demand for a heating cooker which has a simple configuration, does not require a switching resistance, and can quickly obtain the required accuracy.

As a second problem, the resistance of a negative characteristic element such as a thermistor generally used for temperature detection becomes extremely large as the temperature decreases, and the temperature of a positive characteristic element such as a posistor increases. When the resistance becomes low, the resistance value becomes extremely small. In comparison with the measured resistance value in the normal temperature range, the disconnection cannot be detected even with the minimum resolution of the AD conversion. There is a problem that a circuit for detection is required. Therefore, there is a demand for a heating cooker having a simple configuration and capable of accurately detecting disconnection of a sensor.

A third problem is that when the temperature of a negative characteristic such as a thermistor generally used for temperature detection becomes high, the resistance value becomes extremely small, and when the temperature of a positive characteristic element such as a posistor becomes low, the temperature becomes low. The resistance value becomes extremely large, and in comparison with the measured resistance value in the normal temperature range, even at the minimum resolution, it is not possible to accurately distinguish abnormally high temperature detection for safety and the high temperature range used for normal tempura cooking etc. Therefore, there has been a problem that a resistor dedicated for detecting abnormally high temperature is required or a circuit for detecting abnormally high temperature is required. Therefore, there is a demand for a heating cooker having a simple configuration and capable of accurately detecting the temperature in the high temperature range of the sensor.

A fourth problem is that the deep-fried food function of the conventional cooking device detects a drop in the temperature of the oil when the food is thrown in while the temperature of the oil is stable, such as when cooking with a tempura. However, in practice, the temperature of the sensor dropped after the oil temperature dropped significantly, so there was a problem that it was slightly delayed to increase the heat as the food was put in. . In addition, when the amount of hot water decreases and water is added while keeping the hot water in the electric water heater that is a part of the heating cooker, the conventional electric water heater detects a drop in the hot water temperature and increases the thermal power. However, many of them have a function to boil again, but in reality, the temperature of the sensor drops after the water temperature drops considerably, so there was a problem that the addition of a small amount of water could not detect the addition of water .

For this reason, there is a demand for a heating cooker that adjusts the heating power sensitively according to a change in temperature such as the input of food.

A fifth problem is that if the temperature range that can be measured with a single measurement resistor is set narrow in order to increase the temperature measurement accuracy, it takes time to switch the resistance. For example, there is a problem that it is delayed to detect a sudden rise in the load temperature when cooking is performed accidentally while the heat is strong and the food is burned due to lack of moisture. For this reason, there is a demand for a cooking device that prioritizes the measurement speed over the measurement accuracy when the load temperature rises rapidly.

As a sixth problem, when the temperature range in which one measurement resistor can measure is set narrow to improve the temperature measurement accuracy, it takes time to switch the resistance. There is a problem that after detecting the input of food and increasing the thermal power, it is delayed to detect that the temperature starts to rise again, and cooking will continue for a while while the thermal power is too high. Was. For this reason, there is a demand for a cooking device that prioritizes the measurement speed over the measurement accuracy when the load temperature drops rapidly.

Further, as a seventh problem, it is necessary to detect the boiling of water by changing the time required to raise the unit temperature by setting the accuracy of the measurement high, and to maintain the oil at an appropriate temperature using fuzzy inference. If the temperature detected by the sensor fluctuates due to the convection of water or oil, the boiling detection of water may not be successful, or the appropriate temperature of oil may not be maintained stably. For this reason, there is a demand for a cooking device capable of stably detecting the temperature in any state.

Therefore, even if the temperature detected by the sensor fluctuates due to the convection of water or oil, there is a need for a heating cooker that can properly detect boiling and maintain an appropriate oil temperature.

As an eighth problem, in the actual temperature detection processing, although the temperature change can be captured by the processing of the least significant 2 bits or 3 bits, the processing is performed at 10 bits of the full scale. There is a problem that it takes time and processing is slow. Therefore, there is a demand for a heating cooker that is highly accurate and sensitive to temperature changes.

A ninth problem is that when processing is performed only with the lower bits of the AD input in order to increase the measurement speed, when the measured value of the data of a plurality of lower bits of the AD input is the lowest, Has the problem that the data added by one at the top is exactly the same. For this reason,
There is a need for a heating cooker that can stably measure temperature.

Further, as a tenth problem, when a power failure or the like occurs when processing is performed only with the lower bits of the AD input in order to increase the measurement speed, depending on the temperature change during that time, the lower multiple bits may be lost. There has been a problem that a true AD input measurement value cannot be determined from data alone. For this reason,
There is a demand for a heating cooker that can stably and accurately measure temperature at high speed in any state.

[0018]

According to the present invention, an input to a control circuit of a temperature detecting means is performed using an analog-to-digital conversion input of a microcomputer constituting the control circuit. The measurement accuracy of the AD input is changed according to the state of the temperature input of the temperature detecting unit or the state of the control unit for adjusting the heating power of the heating unit. This provides an effect that it can be applied to both the case where the accuracy of temperature detection is required and the case where the speed of detection is required.

In order to solve the above-mentioned second problem, the present invention improves the measurement accuracy of the AD input when the temperature measured by the temperature detecting means is equal to or lower than a predetermined temperature. The effect that the disconnection failure of the thermistor of the temperature sensor can be accurately detected is obtained.

In order to solve the third problem, the present invention is to improve the measurement accuracy of the AD input when the temperature measured by the temperature detecting means is equal to or higher than a predetermined temperature. An effect that an abnormal temperature rise can be accurately detected is obtained.

In order to solve the fourth problem, the present invention increases the measurement accuracy of the AD input when the change time of the AD input of the temperature detecting means for each predetermined input unit is equal to or longer than a predetermined time. With such a configuration, it is possible to obtain an effect that it is possible to sensitively detect the input of food, the addition of water, and the like.

In order to solve the fifth problem, the present invention changes the measurement accuracy of the AD input, and when the accuracy is increased, if a sudden rise in temperature over a predetermined level is detected,
Since the measurement accuracy is reduced, it is possible to obtain an effect that it is possible to quickly cope with an abnormal state such as scorching of the cooked product under load.

In order to solve the above-mentioned sixth problem, the present invention changes the measurement accuracy of the AD input, and when the accuracy is increased, if a sudden drop in temperature over a predetermined level is detected,
Since the measurement accuracy is reduced, it is possible to obtain an effect that it is possible to quickly cope with a state such as the input of the food.

Further, in order to solve the seventh problem, the present invention reduces the temperature of the load to be measured by lowering the measurement accuracy when the measured value of the AD input rises or falls and is not stable. An effect is obtained that it is possible to stably determine whether the image is in the upward trend or the downward trend.

Further, in order to solve the eighth problem, the present invention sets the measurement accuracy of the AD input low, determines only the upper bit of the AD input value, sets the measurement accuracy high, and sets the measurement accuracy lower. Since only bits are measured, an effect is obtained in that only processing of data in a necessary range is required.

In order to solve the ninth problem, according to the present invention, when the measurement accuracy is set high and only the lower bits of the AD input are measured, the input value is set to the lower limit or
When the upper limit value is reached, the measurement accuracy is lowered to measure the upper plurality of bits, and an effect of preventing erroneous determination of data can be obtained.

In order to solve the tenth problem, according to the present invention, the measurement accuracy is set high and the lower bit of the AD input is set.
Only when measuring, when a predetermined signal is input to the control means, the measurement accuracy is reduced to measure the upper bit, and when the operation of the heating cooker changes Also, there is an effect that the operation can be returned to an appropriate measurement accuracy without erroneous determination and a stable operation can be obtained.

[0028]

DESCRIPTION OF THE PREFERRED EMBODIMENTS In the cooking device according to the first aspect of the present invention, the input to the control circuit of the temperature detecting means is performed by using an analog-to-digital conversion input of a microcomputer constituting the control circuit. In addition, according to the state of the temperature input of the temperature detection means or the state of the control means for adjusting the heating power of the heating means, the measurement accuracy of the AD input is changed, whereby the measurement accuracy is required. And the case where the measurement speed is prioritized can be changed each time.

According to a second aspect of the present invention, in the heating cooker according to the first aspect, when the temperature measured by the temperature detecting means is equal to or lower than a predetermined temperature, the A
The measurement accuracy of the D input is improved so that the temperature measurement element is at a low temperature, or a disconnection failure occurs when the temperature detection element has a negative characteristic, and a short-circuit failure occurs when the element has a positive characteristic. This has the effect of increasing the measurement accuracy.

According to a third aspect of the present invention, in the heating cooker according to the first aspect, when the temperature measured by the temperature detecting means is equal to or higher than a predetermined temperature, the A
This is to increase the measurement accuracy of the D input, and when the temperature of the heating load rises above a predetermined temperature, the measurement accuracy is increased to detect a detailed temperature rise. Is what you get.

According to a fourth aspect of the present invention, there is provided the heating cooker according to the first aspect, wherein a change time for each predetermined input unit to the AD input of the temperature detecting means is longer than a predetermined time. In addition, the measurement accuracy of the AD input is improved, and an effect that a small change in the temperature state can be detected when the state of the heating load is stable is obtained.

According to a fifth aspect of the present invention, in the heating cooker according to the first aspect, when the measurement accuracy of the AD input is changed to increase the accuracy, the temperature of the heating cooker may exceed a predetermined value. When a sudden rise in the temperature of the load is detected, the measurement accuracy is reduced, so that when the temperature of the load changes, the effect of quickly responding to the temperature change can be obtained.

According to a sixth aspect of the present invention, in the cooking device of the fifth aspect, when the measurement accuracy of the AD input is changed and the accuracy is increased, the temperature of the cooking device becomes higher than a predetermined temperature. If a sudden drop in the temperature of the load is detected, the measurement accuracy is reduced, and thereby, when the temperature of the load changes, the effect of quickly responding to the temperature change can be obtained. It is.

According to a seventh aspect of the present invention, in the heating cooker according to the fifth aspect, when the measurement accuracy of the AD input is set to be high, the measured temperature is the previously measured temperature. When the temperature does not rise continuously for a predetermined number of times or when it does not drop for a predetermined number of times, the measurement accuracy is reduced, and when the measurement temperature is not stable, the measurement accuracy is reduced. Things.

In the heating cooker according to the present invention, the measuring accuracy of the AD input is set low and only the upper bit of the AD input value is determined. The measurement accuracy is set high and the lower bits
By measuring only the measurement, it is possible to obtain an effect that high-precision measurement can be quickly performed.

In the cooking device according to the ninth aspect of the present invention, when the measurement accuracy is set high and only the lower bits of the AD input are measured, the input value is set to the lower limit or the upper limit. In the event that the measurement data becomes inaccurate, the measurement accuracy will be reduced and the measurement of the upper two or more bits will be performed. What you get.

In the heating cooker according to the tenth aspect of the present invention, when a predetermined signal is input to the control means when the measurement accuracy is set high and only the lower bits of the AD input are measured. When the operation mode of the heating cooker is changed by lowering the measurement accuracy and performing the measurement of the upper bit, the measurement of the temperature is performed over the entire measurement range of the AD input. To get the action.

[0038]

Embodiments of the present invention will be described below with reference to the drawings. FIG. 1 is a block diagram showing the configuration of the first to tenth embodiments of the present invention. In FIG. 1, reference numeral 1 denotes a heating means for heating a load, in which case a heater is used in this case. In the case of an induction heating type heating cooker, a heating coil corresponds to this. Reference numeral 2 denotes a control circuit, which is a drive circuit for connecting a power supply to a heater of the heating means 1 by a relay or the like.
A microcomputer 2b having an AD conversion input switchable between 10-bit and 10-bit accuracy, a temperature detection circuit 2c
And the like. Reference numeral 3 denotes a thermistor of a temperature sensor for detecting the temperature of the load. The microcomputer 2b and the temperature detection circuit 2c are driven by a 5V DC reference power supply.

In this configuration, a voltage obtained by dividing the DC reference power supply of 5 V by the resistance value of the thermistor 3 and R1 is inputted to the AD input terminal of the microcomputer 2b, whereby the temperature of the load is calculated from the resistance value of the thermistor 3. It is what is being measured.

In this embodiment, the thermistor of the negative temperature detecting element is used. However, the effect of the present invention can be equally obtained by using a negative temperature detecting element or a positive temperature detecting element. Things.

(Embodiment 1) A first embodiment of the present invention is specifically shown in FIG. Thermistor 3 has a B constant 4215 (5
0 ° C. to 200 ° C.), and its resistance 875 at 200 ° C.
Assuming that Ω, at about 140 ° C., the AD input becomes about の of the DC reference power supply of 5 V, and when using an 8-bit AD conversion input, the temperature change per AD input digit is also about 0.5 ° C. It is converted.

When the temperature rises or falls, the amount of change in temperature per digit increases. Therefore, when the temperature reaches a predetermined temperature, that is, a predetermined AD input value, AD
The conversion accuracy is switched to 10 bits.

(Embodiment 2) FIG. 2 shows the operation of the second embodiment of the present invention. In the circuit of the temperature detecting circuit 2c and the thermistor 3 as shown in FIG. 1, as shown in FIG.
At 0 ° C., 1.7 MΩ. At this time, the AD input value is about 0.05 V with respect to the DC reference power supply 5 V. At this time, 8 bits
Temperature change per digit per resolution is about 1
℃ is exceeded. At this point, the resolution of AD conversion is 10b
By switching to "it", the microcomputer 2b can measure up to about 0.3.degree. C. as the minimum temperature change per unit digit measured by the microcomputer 2b. Can,
The threshold value for determining whether the thermistor 3 is broken or extremely low can be -10 ° C or less.

(Embodiment 3) FIG. 2 shows the operation of a heating cooker according to a third embodiment of the present invention. In the circuit of the temperature detecting circuit 2c and the thermistor 3 as shown in FIG. 1, as shown in FIG. 2, it is 1075Ω at about 190 ° C., and the AD input value is about 4.7V with respect to the DC reference power supply 5V. At this time, the temperature change per digit exceeds about 1 ° C. for the resolution of 8 bits. At this point, by switching the resolution of the AD conversion to 10 bits, it becomes possible to capture the lowest temperature change per unit 1 digit measured by the microcomputer 2b up to 0.25 ° C. It is possible to measure the temperature accurately even thereafter.

(Embodiment 4) FIG. 3 is a timing chart showing the operation of the fourth embodiment of the present invention. FIG. 3 shows an example in which the water temperature is measured in a case where a kettle is boiling in a load pot or a jar pot or the like.

As the water temperature rises, the change in the voltage input to the AD input gradually becomes smaller, ie, 1di.
The time required to change the git gradually increases. At this time, when the time required to change per digit exceeds 5 seconds, the measurement accuracy of the AD input is changed to 10 bits. Then, the measurement time data of the inclination is measured at a value of 1/4, and the time required for 1 digit is determined to be the boiling detection in 20 seconds with the resolution of 8 bits, but the detection of the boiling is determined in 5 seconds with the resolution of 10 bits. And more accurate measurements can be made.

The present invention is also effective when the oil is heated to an appropriate temperature and stabilized for cooking tempura or the like.

(Embodiment 5) FIG. 4 is a timing chart showing the operation of the fifth embodiment of the present invention. FIG. 4 shows an example of a temperature change when cooking boiled food in a loaded pot. When the stew is cooked during cooking, the temperature of the cooked food is stable at about 90 ° C.
The thermal power is adjusted by measuring the temperature change with a measurement accuracy of 10 bits. During this cooking, water evaporates and the food becomes scorched and the temperature rises sharply. If the time required for a temperature rise change per digit becomes less than 0.5 seconds, the measurement accuracy is reduced and the measurement is switched to 8-bit measurement. I have. As a result, the temperature can be quickly measured by the AD input, so that the heating is stopped before the burning of the food is too late.

(Embodiment 6) FIG. 5 is a timing chart showing the operation of the sixth embodiment of the present invention. FIG. 4 shows an example of a temperature change when fried food is cooked in a load pan. When preheating the oil during fry cooking, the oil temperature is stable at about 180 ° C, so measure the temperature change with a measurement accuracy of 10 bits and adjust the heating power by fuzzy control etc. to keep the temperature constant I keep it.

At this time, when the food is put in the oil,
The oil temperature drops rapidly. Here, once a sudden drop in the temperature of the oil is detected, it is determined that the food has been introduced, and then the measurement accuracy is switched to 8 bits. As a result, the temperature can be quickly measured by the AD input, so that the heating power can be quickly adjusted each time as the heating of the food proceeds.

(Embodiment 7) FIG. 6 is a timing chart showing the operation of the seventh embodiment of the present invention. FIG. 6 shows an example in which the water temperature is measured in a case where a kettle is boiling in a load pot or a jar pot or the like.

Here, in the case where precise measurement is performed at 10 bits, if the temperature change fluctuates due to convection in the pan, for example, if the temperature changes from b + 5 to b + 8 in FIG. The data that the temperature that has fallen on the contrary is input. When such a temperature change occurs, that is, when monotonically increasing data should be input continuously, otherwise, the measurement accuracy is switched to 8 bits. Then, as shown in FIG. 6, the data from a to a + 3 can be handled as monotonically increasing.

(Embodiment 8) FIG. 7 shows the operation of an eighth embodiment of the present invention. In FIG. 7, the vertical axis indicates the change in the data of the upper 2 bits out of the data of 10 bits.
The data changes in the order of "00", "01", "10", and "11" from the bottom of the D input. The horizontal axis indicates the change in the lower 8 bits of the 10-bit data, and data "00" to "FF" are input in hexadecimal notation from the range A to D in the lower diagram of the AD input. I have.

In the eighth embodiment, first, 10b
It measures the upper 2 bits of the resolution of the it, measures the range of the measurement range from A to D, holds it as data, and then quickly measures only the lower 8 bits.

(Embodiment 9) FIG. 7 shows the operation of the ninth embodiment of the present invention. In the ninth embodiment of the present invention, FIG.
In the measurement area of the area B, the data is hexadecimal “0”.
When the value becomes "0", the data of the upper 2 bits is checked once, it is confirmed that the data has moved to the measurement area of the area A, and the measurement of the lower 8 bits is continued thereafter.

Also, when the data becomes hexadecimal "FF" in the measurement area of the area B in FIG. 7, the data of the upper two bits is checked once and it is confirmed that the data has moved to the measurement area of the area C. The measurement in the subsequent lower 8 bits is continued.

(Embodiment 10) In a tenth embodiment of the present invention, the user operates the heating cooker, for example, from cooking with constant power to cooking with fried food in which the power is adjusted at constant temperature. When the mode is switched, or when the commercial power supply is interrupted and the heating is temporarily stopped and then resumed, as shown in FIG.
After confirming the data of t and confirming the measurement areas of the areas A to D, the measurement in the subsequent lower 8 bits is continued.

[0058]

As described above, according to the first aspect of the invention, the input to the control circuit of the temperature detecting means is performed by using the analog-to-digital conversion input of the microcomputer constituting the control circuit, and the temperature is detected. The state of the temperature input of the means,
Alternatively, according to the state of the control means for adjusting the heating power of the heating means, the measurement accuracy of the AD input is changed.

Thus, the case where the measurement accuracy is required and the case where the measurement speed is prioritized can be changed each time, and an effect of obtaining a heating cooker capable of performing stable temperature control can be obtained.

According to the second aspect of the present invention, in the heating cooker according to the first aspect, when the resistance value of the thermistor of the temperature detecting means is equal to or more than a predetermined resistance value, the measurement accuracy of the AD input is increased. This has the effect of increasing the measurement accuracy when the temperature measurement thermistor is in a low temperature or disconnected state, and has the effect of obtaining a cooking device that can stably detect a thermistor disconnection failure. can get.

According to the third aspect of the present invention, in the heating cooker according to the first aspect, when the resistance value of the thermistor of the temperature detecting means is equal to or less than a predetermined resistance value, the measurement accuracy of the AD input is increased. Therefore, when the temperature of the load being heated has risen above a predetermined temperature, the measurement accuracy can be increased to detect a detailed temperature rise, and the temperature of the load and the food in it can be reduced. Even if the temperature is abnormally high, it is possible to accurately detect the abnormal state and distinguish it from normal high-temperature cooking such as tempura cooking so that a safe and easy-to-use heating cooker can be obtained. Is obtained.

According to the fourth aspect of the present invention, in the heating cooker according to the first aspect, when a change time of the AD input of the temperature detection means for each predetermined input unit is equal to or longer than a predetermined time, the AD input is performed. The measurement accuracy is improved, and a small change in the temperature state can be detected when the state of the heating load is stable. As a result, it is possible to accurately detect that the temperature of the food is stable, for example, to detect the boiling of water and to keep the temperature of the tempura oil at a temperature suitable for cooking, and conversely, in a state where the temperature of the food is stable. It is possible to obtain a heating cooker that can accurately detect the deviation from the temperature, that is, the addition of water while keeping the hot water in the jar pot, and the detection of the fact that the food has been put in by the tempura cooking. The effect can be obtained.

According to the fifth aspect of the present invention, in the cooking device according to the first aspect, when the measurement accuracy of the AD input is changed and the accuracy is increased, a sudden rise in temperature over a predetermined level is detected. In such a case, the measurement accuracy is reduced, so that if there is a change in the load temperature, the measurement can quickly follow the change, and the appropriate heating power can be set. The effect that a heating cooker can be obtained can be obtained.

According to the sixth aspect of the present invention, in the heating cooker according to the fifth aspect, when the measurement accuracy of the AD input is changed and the accuracy is increased, a sudden decrease in temperature over a predetermined level is detected. In this case, the measurement accuracy is reduced, so that when there is a change in the load temperature, the change in the load temperature can be quickly followed and the appropriate heating power can be set. The effect that a heating cooker can be obtained can be obtained.

According to the seventh aspect of the present invention, in the heating cooker according to the fifth aspect, when the measurement accuracy of the AD input is set to be high, the measured temperature is more than the previously measured temperature by a predetermined number of times. When the temperature does not rise continuously or does not drop continuously for a predetermined number of times, the measurement accuracy is reduced. When the measurement temperature is not stabilized, stable temperature control is performed by reducing the measurement accuracy. The effect that the heating cooker which can do it can be obtained is acquired.

According to the eighth aspect of the present invention, in the cooking device according to the first aspect, after the measurement accuracy of the AD input is set to be low and only the upper bit of the AD input value is determined, the measurement accuracy is reduced. By setting high and measuring only the lower bits, it is possible to obtain a heating cooker that can quickly perform high-accuracy measurement, and that can measure temperature with satisfactory accuracy and speed of temperature measurement. The effect is obtained.

According to the ninth aspect of the present invention, when only the lower bit of the AD input is measured with the measurement accuracy set to be high, when the input value becomes the lower limit or the upper limit, By lowering the measurement accuracy and measuring the upper multiple bits, when the measurement data carries or drops, it measures the entire measurement range of the AD input. In addition, it is possible to obtain a heating cooker which can measure a temperature satisfying both the temperature and the speed and can also prevent the post-determination of the temperature.

According to the tenth aspect of the present invention, when a predetermined signal is input to the control means when only the lower bits of the AD input are measured while the measurement accuracy is set to be high, the measurement accuracy is reduced. When the operation mode of the heating cooker changes due to the measurement of the upper bits by dropping the temperature, the measurement of the temperature is performed over the entire measurement range of the AD input, so that the commercial power supply can be measured. The effect is obtained that it is possible to obtain a heating cooker that can prevent erroneous determination of the temperature even when a power failure occurs.

[Brief description of the drawings]

FIG. 1 is a block diagram showing a configuration of a heating cooker according to first to tenth embodiments of the present invention.

FIG. 2 is a timing chart showing the operation of the cooking device according to the second and third embodiments of the present invention.

FIG. 3 is a timing chart showing the operation of the heating cooker according to the fourth embodiment of the present invention.

FIG. 4 is a timing chart showing the operation of the heating cooker according to the fifth embodiment of the present invention.

FIG. 5 is a timing chart showing the operation of the heating cooker according to the sixth embodiment of the present invention.

FIG. 6 is a timing chart showing the operation of the heating cooker according to the seventh embodiment of the present invention.

FIG. 7 is a timing chart showing the operation of the heating cooker according to the eighth to tenth embodiments of the present invention.

FIG. 8 is a block diagram showing a configuration of a conventional heating cooker.

FIG. 9 is a timing chart showing the operation of a conventional cooking device.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Heating means 2 Control circuit 2a Drive circuit 2b Microcomputer 2c Temperature detection circuit 3 Thermistor

────────────────────────────────────────────────── ─── Continuation of the front page (56) References JP-A-5-41276 (JP, A) JP-A-9-89588 (JP, A) (58) Fields investigated (Int. Cl. ⁷ , DB name) H05B 6/12 H05B 3/00

Claims (10)

(57) [Claims] 1. A heating means for heating a food, a temperature detecting means for measuring a temperature of the food or a container containing the food, and a microcomputer for adjusting the heating power of the heating means by an input of the temperature detecting means. A control circuit using the same, the input to the control circuit of the temperature detection means is performed using an analog-to-digital conversion input of a microcomputer constituting the control circuit, and the state of the temperature input of the temperature detection means, Alternatively, a heating cooker that changes the measurement accuracy of the analog-to-digital conversion input of the microcomputer according to the state of the control means for adjusting the heating power of the heating means. 2. The cooking device according to claim 1, wherein when the temperature measured by the temperature detecting means is equal to or lower than a predetermined temperature, the measurement accuracy of the analog-to-digital conversion input of the microcomputer is increased. 3. The heating cooker according to claim 1, wherein when the temperature measured by the temperature detecting means is equal to or higher than a predetermined temperature, the measurement accuracy of the analog-to-digital conversion input of the microcomputer is increased. 4. The heating device according to claim 1, wherein when the change time of each predetermined input unit to the analog-to-digital conversion input of the microcomputer of the temperature detecting means is longer than a predetermined time, the measurement accuracy of the input is increased. Cooking device. 5. The method according to claim 1, wherein the measurement accuracy of the analog-to-digital conversion input of the microcomputer is changed, and when the accuracy is increased, if a sudden rise in temperature over a predetermined level is detected, the measurement accuracy is reduced. The heating cooker according to 1. 6. The method according to claim 1, wherein the measurement accuracy of the analog-to-digital conversion input of the microcomputer is changed, and when the accuracy is increased, if a sudden drop in temperature over a predetermined level is detected, the measurement accuracy is reduced. Item 2. A heating cooker according to Item 1. 7. When the measurement accuracy of the analog-to-digital conversion input of the microcomputer is set to be high, the measured temperature does not continuously increase by a predetermined number of times or does not continuously decrease by a predetermined number of times from the temperature measured last time. In case,
2. The cooking device according to claim 1, wherein the measurement accuracy is reduced. 8. The measurement accuracy of the analog-to-digital conversion input of the microcomputer is set low, only the upper bit of the input value is determined, and then the measurement accuracy is set high to measure only the lower bit. The cooking device according to claim 1. 9. When the measurement accuracy is set high and only the lower bits of the analog-to-digital conversion input of the microcomputer are measured, and when the input value becomes the lower limit or the upper limit, the measurement accuracy is reduced. Drop the top multiple b
The heating cooker according to claim 8, wherein it is measured. 10. When a predetermined signal is input to the control means when only the lower bits of the analog-to-digital conversion input of the microcomputer are measured by setting the measurement accuracy to be high, the measurement accuracy is reduced. 9. The heating cooker according to claim 8, wherein the measurement of the upper bits is performed.