JPH0466564B2 - - Google Patents

Description

[Detailed Description of the Invention] [Industrial Application Field] The present invention relates to a microcomputer-controlled rice cooker, and in particular, detects an abnormality in rice cooking capacity determination (combined rice determination) during rice cooking operation to detect an empty cooking state. This invention relates to a microcomputer-controlled rice cooker equipped with a detection function.

[Conventional technology]

Traditionally, with the aim of cooking rice deliciously,
A controller equipped with a temperature sensor and a microcomputer measures the temperature of the rice cooking pot, inputs this temperature and temperature rise into the microcomputer, determines the rice cooking capacity, and performs appropriate power control according to the rice cooking capacity. A microcomputer-controlled rice cooker has been developed.

In an automatic rice cooker that cooks rice under the control of such a microcomputer, this is the rice cooking process. Water absorption process, rice cooking capacity determination process,
Control of rice cooking processes such as a cooking process, a boiling maintenance process, a first steaming process, an additional cooking process, a second steaming process, and a warming process is automatically performed under program control of a microcomputer.

[Problem that the invention seeks to solve]

However, in such a microcomputer-controlled rice cooker, rice cooking process control and heat retention control are automatically performed by microcomputer programs, so for example, rice can be cooked without putting rice, water, or other contents into the inner pot. Even when the start switch is turned on, the rice cooking process is started, and the rice cooking process progresses sequentially until all the rice cooking processes are performed and the rice cooking process continues until the warm state is reached. As a result, the rice cooker becomes dry-cooked, and the temperature of the inner pot becomes abnormally high during the cooking process, which has a negative effect on the rice cooker itself and the rice cooking controller board.

The present invention has been made to solve the above problems.

An object of the present invention is to provide a means for detecting abnormal data on the amount of cooked rice that results in an empty cooking state as a part of the rice cooking capacity determination means for a rice cooking operation, and to determine whether the detected abnormal data is data for an empty cooking state. A means is provided to check whether the rice is cooked by the temperature of the rice cooker and abnormal data, and when the data indicating the dry cooking state is confirmed, the rice cooking operation is stopped and a means is provided to display or notify the dry cooking state. An object of the present invention is to provide a microcomputer-controlled rice cooker having the following characteristics.

The above and other objects and novel features of the present invention will become apparent from the description of this specification and the accompanying drawings.

[Means for solving problems]

In order to achieve the above object, the present invention uses a temperature sensor and a microcomputer provided near the rice cooker to control the temperature change of the rice cooker within a predetermined range.
The microcontroller has a rice cooking capacity determination means for determining the rice cooking capacity by measuring the time required for the temperature to pass between two points, and cooks rice with an appropriate heating power according to the rice cooking capacity determined by the rice cooking capacity determination means. In the computer-controlled rice cooker, a part of the rice cooking capacity determination means is provided with means for detecting abnormal data on the amount of rice that is in an empty cooking state, and whether or not the detected abnormal data is data in an empty cooking state. We will provide a means to check the temperature of the rice cooker and abnormal data.
The present invention is characterized in that, when the data of the dry cooking state is confirmed, the rice cooking operation is stopped and a means is provided for displaying or notifying the dry cooking state.

[Effect]

According to the above means, in the microcomputer-controlled rice cooker, the time required for the temperature change of the rice cooker to pass between two predetermined points is measured using a temperature sensor provided near the rice cooker and the microcomputer. The empty cooking state is detected by detecting an abnormality in the rice cooking capacity determination means that determines the rice cooking capacity. In other words, when the rice cooking operation is started with no contents in the inner pot, the rice cooking capacity determination step is entered, and the rice cooking pot is heated (into an empty cooking state), the temperature rise rate of the inner pot is It quickly reaches a high temperature. This state is detected by temperature detection to determine whether the inner pot has reached a predetermined high temperature, and by time detection to detect whether the time to reach the predetermined temperature is shorter than a predetermined time. Detects empty cooking status. Then, the rice cooking operation is stopped and the empty cooking state is notified. According to this, by detecting an abnormality in the rice cooking capacity determining means, the empty cooking state is detected and notified. This empty cooking state can be detected by detecting temperature abnormality or time abnormality in the rice cooking capacity determining means before the rice cooker reaches an abnormally high temperature due to the next process of cooking or maintaining boiling. The main unit will not be damaged by abnormally high temperatures. Furthermore, providing a means for detecting such an empty cooking state in this microcomputer-controlled rice cooker does not require any special hardware, and only a few judgment steps can be performed in the rice cooking capacity judgment process. Since it only needs to be added, the cost will not be high.

〔Example〕

Embodiments of the present invention will be described below with reference to the drawings.

FIG. 1 is a partially cutaway side view of a microcomputer-controlled rice cooker according to an embodiment of the present invention. 1st
In the figure, 1 is a rice cooker main body, 2 is an inner pot, and 3 is an inner pot storage container for storing the inner pot 2. Further, 4 is a rice cooking heater, and 5 is a temperature sensor composed of a thermistor or the like that is in contact with the bottom of the inner pot 2. 6 is a control unit incorporating a microcomputer and the like. 7 is a rice cooking switch, and 8 is a heat-retaining heater.

FIG. 2 is a block diagram showing the configuration of the main parts of the control unit 6. As shown in FIG. In FIG. 2, 4 is a rice cooking heater, and 5 is a temperature sensor composed of a thermistor or the like. Moreover, 7 is a rice cooking switch.
10 is a microcomputer, which includes a processing unit CPU, memory RAM, and program memory.
It has a built-in ROM, an input port with an analog/digital conversion function, an output port that outputs a control output signal, etc. Reference numeral 11 denotes an energization control means such as a triax, which controls the heating power by controlling the pulse width applied thereto. 12 is a commercial AC power source. 13 is a light emitting diode as a display means
It is an LED, and 14 is a buzzer as a notification means.
These light emitting diodes 13 and buzzer 14
is for displaying and notifying the status of the rice cooking process, abnormal conditions, etc.

Next, the operation of the microcomputer-controlled rice cooker configured as described above will be explained.

When you put the desired amount of rice and the appropriate amount of water into the inner pot 2 and turn on the rice cooker switch 7, the microcomputer 10 reads the program memory in it.
Power control for heating in the rice cooking process is started according to the processing steps of the rice cooking program stored in the ROM. At this time, the microcomputer 10 converts the voltage output from the temperature sensor 5 into a digital quantity from the input port of the analog/digital conversion function, performs processing to convert it into temperature, and determines the input temperature. Various rice cooking processes are controlled based on the temperature determination results. To explain the outline of this rice cooking process, in the initial stage of rice cooking, a water absorption process is performed in which the heating power is reduced and the rice absorbs water. Next, the heating power is increased to rapidly raise the temperature to perform a boiling step, and then a boiling maintenance step to maintain boiling. This boiling maintenance process continues, and when the rice absorbs enough water and the moisture at the bottom of the inner pot disappears and reaches a predetermined temperature, the microcomputer detects this temperature and turns off the heating heater, and the boiling maintenance process is continued. end. Next, a first shading process, an additional cooking process, and a second shading process are performed, and finally, a warming process is reached, and the rice cooking process is completed.

FIG. 3 is a diagram showing an example of a rice cooking temperature curve showing the temperature change of the inner pot 2 when rice is cooked by such a microcomputer-controlled rice cooker. In FIG. 3, the area indicates the water absorption process,
The area indicates the cooking process including the rice cooking capacity determination process, and the area indicates the boiling maintenance process. In addition, the area reduces the heating power for cooking rice to zero. It shows the uneven process. The region cooking process is a process in which the heating power is increased, the temperature is rapidly raised to boil, and the process continues to the boiling maintenance process. Accordingly, the rice cooking capacity is determined, and the heating power is controlled to be appropriate according to the rice cooking capacity to maintain boiling appropriately, and the next boiling maintenance step is performed.

FIG. 4 is a flowchart showing the rice cooking capacity determination and control operation of the cooking process performed by the microcomputer. The control operation of this cooking process will be explained with reference to FIG.

When the water absorption process is completed, the cooking process begins and the processes starting from step 21 are performed. First step 21
, turn on the rice cooker heater at full power. Next, in step 22, it is determined whether the temperature at the bottom of the inner pot has reached 100℃, and if it has not reached 100℃,
Continue energizing the rice cooking heater. The temperature of the inner pot is 100
When the temperature reaches ℃, the electricity to the rice cooking heater is turned off (step 23). Then, proceed to step 24 and check the T1 counter (cooking capacity detection counter).
Starts the time counting operation and enters the rice cooking capacity determination process. Next, in step 25, it is determined whether the temperature of the inner pot is an abnormal temperature of 110°C or higher. Even if the power to the rice cooking heater is turned off, the detected temperature of the inner pot will rise for a while, but in normal rice cooking mode (not dry cooking mode), this increase in detected temperature will be slight, so this rice cooking heater An abnormal rise in temperature after the device is turned off is detected to determine whether or not the device is in a dry cooking state. If the detected temperature of the inner pot is 110°C or higher in step 25, it is determined that the rice is in an empty cooking state, so the process proceeds to step 36 to stop the rice cooking operation (turn off the warming heater and stop the rice cooking process from proceeding). In step 37, the empty cooking status is displayed by the light emitting diode 13 and notified by the buzzer 14, and the process is terminated.

On the other hand, in step 25, if the temperature of the inner pot is detected and it is not above 110℃, the temperature of the inner pot is detected in step 26, and the temperature of the inner pot is detected until the temperature of the inner pot drops to 100℃. , step 25, and step 26 are repeated, and during this time
Continue counting operation of T1 counter. During this period, if the temperature of the inner pot detects an abnormal temperature of 110℃, the process proceeds to step 36, and the temperature of the inner pot increases to 100℃.
℃, the process proceeds to step 27 and the counting operation of the T1 counter is stopped. The processes performed in the series of steps up to this point are the processes of finishing the rice and determining the cooking capacity. The temperature gradient due to heat dissipation is inversely proportional to the heat capacity of the heat dissipating object, so when the rice cooking capacity judgment start temperature is reached, heating is stopped and time counting is started, and when the judgment end temperature is reached, time counting is stopped and time counting is started. The time required for cooking is proportional to the rice cooking capacity.
You can determine the rice cooking capacity. Therefore, the count value by this T1 counter is proportional to the rice cooking capacity. In the next series of steps 28 to 31, the count value of the T1 counter is determined, and the heating output of the rice cooking heater is controlled according to the content of each count value (rice cooking capacity). First, in step 28, if it is determined that the content of the T1 counter is less than or equal to the predetermined value m1, it is determined that this is some kind of abnormal state and that the amount of rice cooked is close to zero and is in a dry cooking state. The process proceeds to step 36, where processing is performed to stop the rice cooking operation, and in step 37, the empty cooking state is displayed and notified, and the process ends. If it is determined in step 28 that the content of the T1 counter is not less than the predetermined value m1, the process proceeds to step 29, where
Determine whether the contents of the T1 counter are between m1 and m2. If the contents of T1 counter are not m1~m2,
Proceed to step 30 and the contents of the T1 counter will be m2.
Determine whether it is ~m3. Here, if the contents of the T1 counter are not m2 to m3, the process proceeds to step 31, where it is determined whether the contents of the T1 counter are between m3 and m4. And the contents of T1 counter are
If it is m1 to m2, the rice cooking heater is controlled and energized so that the heating output becomes Ew (step 32),
If the content of the T1 counter is m2 to m3, the rice cooking heater is controlled and energized so that the heating output becomes Fw (step 33), and the content of the T1 counter is m3 to m3.
If it is m4, the rice cooking heater is controlled and energized so that the heating output becomes Gw (step 34), and if the content of the T1 counter exceeds m4, the rice cooking heater is turned on so that the heating output becomes Hw. It is controlled and energized (step 35). According to the rice cooking capacity determined in this way, the heating power of the rice cooking heater is appropriately controlled to finish the rice and proceed to the next boiling maintenance step.

In this way, the process of determining the rice cooking capacity is performed during the rice cooking process, and through this rice cooking capacity determination process, the rice cooking capacity is determined and the heating power is controlled to be appropriate according to the rice cooking capacity to properly boil the rice. The next boiling maintenance step is carried out while maintaining the boiling temperature. and,
In this process of determining the amount of cooked rice, the abnormality is detected, an empty cooking state is detected, the rice cooking operation is stopped, and the empty cooking state is displayed and notified.

Next, another embodiment will be described. Figures 3 and 4
In the rice cooking operation explained in the figure, the rice cooking capacity determination process in the rice cooking process first boils the rice at a temperature of 100°C in the inner pot, and then counts the heat dissipation time to determine the rice cooking capacity. This is what we do. In other words, if you first turn on the rice cooker and start cooking, and then turn off the rice cooker after the inner pot reaches 100℃, the temperature of the inner pot will rise further due to the residual heat of the rice cooker, and then it will cool down. The rice cooking capacity is determined by measuring the time it takes for the temperature to reach 100°C again. By the way, the rice cooking capacity determination step in this cooking process can also be configured to determine the rice cooking capacity by measuring the time during the process of raising the temperature of the inner pot to 100° C. during the cooking process. An example of this case will be described next as another embodiment.

FIG. 5 is a diagram showing an example of a rice cooking temperature curve showing temperature changes in the inner pot when rice cooking control is performed such that the rice cooking capacity is determined during the cooking process.

In FIG. 5, the area indicates the water absorption process, the area indicates the cooking process including the rice cooking capacity determination process, and the area indicates the boiling maintenance process. In addition, the area reduces the heating power for cooking rice to zero. It shows the uneven process. The region cooking process is a process of increasing the heating power, rapidly raising the temperature, bringing it to a boil, and continuing to the boiling maintenance process, which includes a process of determining the rice cooking capacity, and this rice cooking capacity determination process Accordingly, the rice cooking capacity is determined, and the heating power is controlled to be appropriate according to the rice cooking capacity to maintain boiling appropriately, and the next boiling maintenance step is performed.

FIG. 6 is a flowchart showing the control operation of the microcomputer in the rice cooking process and the rice cooking process when rice cooking control is performed such that the rice cooking capacity is determined during the cooking process. The control operation will be explained with reference to FIG. 6.

When the water absorption process is finished, the cooking process starts and the processes from step 41 are carried out. First step 41
, turn on the rice cooker heater at full power. Next, in step 42, it is determined whether the temperature at the bottom of the inner pot has reached 70°C, and if it has not reached 70°C, the rice cooking heater continues to be energized. When the temperature of the inner pot reaches 70°C, the power to the rice cooking heater is turned off in step 43, and the energization to the rice cooking heater continues to be turned off until 60 seconds have elapsed in step 44. When 60 seconds have elapsed with the power to the rice cooker turned off, the process begins to determine the rice cooking capacity, and in step 45, the T1 counter starts counting the time, and in step 46, the rice cooker is turned on again at full output. As a result, the rice cooker heater continues to be energized until the temperature of the inner pot reaches 100℃. That is, step 47
The temperature of the inner pot is detected, and the rice cooking heater continues to be energized until the temperature of the inner pot reaches 100℃, and the T1 counter continues to count, and when the temperature of the inner pot reaches 100℃, , the process advances to step 48 and the counting operation of the T1 counter is stopped.
Next, in step 49, the rice cooking heater is turned off.
The processes performed in the series of steps up to now are the processes of finishing the rice and determining the cooking capacity. Under constant power heating conditions, the gradient of temperature rise is inversely proportional to the heat capacity (cooking capacity) of the object to be heated, so when the rice cooking capacity determination start temperature is reached, heating is started and stopped, and time counting is started. When the determination end temperature is reached, the time counting is stopped and the time taken is proportional to the rice cooking capacity, so that the rice cooking capacity can be determined. In other words, the count value by this T1 counter is
It is proportional to the cooking capacity.

Next, in order to detect an abnormality in this rice cooking capacity process, in step 50, the temperature of the inner pot is set to 110°C.
It is determined whether or not the abnormal temperature is higher than that.
Even if the power to the rice cooking heater is turned off, the detected temperature of the inner pot will rise for a while, but in normal rice cooking mode (not dry cooking mode), this increase in detected temperature will
Since the amount is small, the abnormal rise in temperature after the rice cooking heater is turned off is detected to determine whether or not the rice is being cooked dry. That is, step 50
If it is determined that the detected temperature of the inner pot is 110℃ or higher, it is determined that the cooking condition is empty, so proceed to step 5.
Proceed to step 1, perform processing to stop the rice cooking operation (turn off the heat retaining heater, return the timer that controls the progress of the rice cooking process to its initial value, etc.), and then proceed to step 5.
In step 2, the empty cooking state is displayed by the light emitting diode 13, and the buzzer 14 is used to notify the empty cooking state, and the process is terminated.

If the temperature of the inner pot is not detected to be 110°C or higher in step 50, the rice is being cooked normally, so in the next series of steps 53 to 56,
The count value of the T1 counter is determined, and the heating output of the rice cooking heater is controlled according to the contents of each count value (rice cooking capacity). First, in step 53,
If it is determined that the content of the T1 counter is less than or equal to the predetermined value m1, it is determined that this is some kind of abnormal state and that the amount of rice being cooked is close to zero and is in a dry cooking state, so in this case, proceed to step 51. , a process is performed to stop the rice cooking process, and in step 52, the empty cooking state is displayed and notified, and the process ends. If it is determined in step 53 that the content of the T1 counter is not less than the predetermined value m1, the process proceeds to step 54, where it is determined whether the content of the T1 counter is between m1 and m2. If the contents of the T1 counter are not between m1 and m2, the process proceeds to step 55, where it is determined whether the contents of the T1 counter are between m2 and m3. here,
If the contents of the T1 counter are not m2 to m3, the process proceeds to step 56 and the contents of the T1 counter are not m3 to m4.
Determine whether or not. Then, if the contents of the T1 counter are m1 to m2, the rice cooking heater is controlled and energized so that the heating output becomes Ew (step 58), and if the contents of the T1 counter are m2 to m3,
The rice cooking heater is controlled and energized so that the heating output becomes Fw (step 59), and the contents of the T1 counter are
If it is m3 to m4, the rice cooking heater is controlled and energized so that the heating output becomes Gw (step 60),
If the content of the T1 counter exceeds m4, the rice cooking heater is controlled and energized so that the heating output becomes Hw (step 57). According to the rice cooking capacity determined in this way, the heating power of the rice cooking heater is appropriately controlled to finish the rice and proceed to the next boiling maintenance step.

In this way, the process of determining the rice cooking capacity is performed during the rice cooking process, and through this rice cooking capacity determination process, the rice cooking capacity is determined and the heating power is controlled to be appropriate according to the rice cooking capacity to properly boil the rice. The next boiling maintenance step is carried out while maintaining the boiling temperature. and,
In the rice cooking amount determination process here, the abnormality is detected, an empty cooking state is detected, and the rice cooking operation is stopped, and the empty cooking state is displayed and notified.

Note that providing an empty cooking state detection means in such a microcomputer-controlled rice cooker does not require any special hardware, and only requires adding a few determination steps in the rice cooking capacity determination and detection process. Therefore, the cost will not be high.

Although the present invention has been specifically described above based on examples, it goes without saying that the present invention is not limited to the above-mentioned examples, and can be modified in various ways without departing from the gist thereof.

〔Effect of the invention〕

As described above, according to the present invention, a part of the rice cooking capacity determining means is provided with a means for detecting abnormal data on the amount of cooked rice that indicates an empty cooking state, and the detected abnormal data indicates an empty cooking state. A means is provided to check whether the data is correct based on the temperature of the rice cooker and abnormal data, and when the data of the empty cooking state is confirmed,
In addition to stopping the rice cooking operation, by providing a means to display or notify the empty cooking status, the empty cooking status can be reliably detected and the rice cooking operation can be stopped before the data becomes abnormal in the next process of cooking. Therefore, the rice cooker itself will not be damaged due to abnormal data.

In addition, the configuration of the rice cooking prevention means requires only adding a few judgment steps in the rice cooking capacity determination detection process, so it is possible to perform both rice cooking capacity determination and rice cooking prevention with a simple configuration. .

[Brief explanation of drawings]

FIG. 1 is a partially cutaway side view of a microcomputer-controlled rice cooker that is an embodiment of the present invention, and FIG. 2 is a block diagram showing the configuration of the main parts of the control unit of the microcomputer-controlled rice cooker of FIG. Figure 3 shows an example of a rice cooking temperature curve showing the temperature change in the inner pot when rice is cooked under microcomputer control, and Figure 4 shows the rice cooking process including the rice cooking capacity determination process performed by the microcomputer. A flowchart showing an example of process control operation, FIG. 5, is as follows:
FIG. 6 is a diagram showing another example of the rice cooking temperature curve showing the temperature change of the inner pot when rice is cooked under microcomputer control. It is a flowchart showing another example. In the figure, 1...Rice cooker main body, 2...Inner pot, 3...Inner pot storage container, 4...Rice cooking heater, 5...Temperature sensor, 6...
Control unit, 7... rice cooking switch, 8... heat retention heater, 10... microcomputer, 11... energization control means, 12... commercial AC power supply, 13... light emitting diode, 14... buzzer.

Claims (1)

[Claims] 1 A temperature sensor and a microcomputer installed near the rice cooker keep the temperature change of the rice cooker within a predetermined range.
The microcontroller has a rice cooking capacity determination means for determining the rice cooking capacity by measuring the time required for the temperature to pass between two points, and cooks rice with an appropriate heating power according to the rice cooking capacity determined by the rice cooking capacity determination means. In the computer-controlled rice cooker, a part of the rice cooking capacity determining means is provided with means for detecting abnormal data on the amount of cooked rice that results in an empty cooking state, and whether or not the detected abnormal data is the temperature for an empty cooking state. The present invention is characterized by providing means for checking the temperature of the rice cooker and abnormal data, and when the data indicating the dry cooking state is confirmed, means for stopping the rice cooking operation and displaying or notifying the dry cooking state. A microcomputer-controlled rice cooker.