JPS61222415A - Cooker - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

DETAILED DESCRIPTION OF THE INVENTION (Field of Industrial Application) The present invention relates to a cooking device that can cook brown rice, rice porridge, etc.

(Prior art and its problems) Conventionally, in electronically controlled rice cookers using a microcomputer, a sensor is provided at the bottom of the pot, such as the outer bottom or outer surface, and the heater is controlled based on the signal from this sensor. This makes it possible to cook rice in an ideal manner, but such conventional rice cookers are commercialized exclusively for cooking white rice, and are suitable for cooking other than white rice, such as brown rice, steamed rice, It was not very desirable for cooking porridge and the like.

That is, a sensor installed at the bottom of the pot can achieve good results in detecting the completion of rice cooking and detecting temperatures in low temperature ranges, but the sensor may be greatly affected by the heat due to the presence of a heater for cooking rice nearby. In addition, since it is greatly affected by the unevenness of the temperature distribution of the food to be cooked, it is not possible to obtain very favorable results in detecting the boiling of the food to be cooked. In order to do this in an ideal way, it is essential to be able to detect the boiling of the food to be cooked, but conventional rice cookers such as those mentioned above cannot accurately detect boiling, and therefore cannot be used to cook brown rice, rice porridge, etc. It was not possible to do so in good conditions.

(Object of the Invention) The present invention has been made in view of the above points, and it is possible to accurately detect the completion of rice cooking and boiling, so that brown rice, rice porridge, etc. can be cooked in good condition. It provides cooking utensils.

(Structure of the Invention) As shown in FIG. 1, the present invention includes a pot that accommodates food to be cooked, a heater that heats the pot and cooks the food.
a first sensor that detects a temperature change at the bottom of the pot;
It is equipped with a second sensor that detects a change in ambient temperature due to heating cooking, and a control means that controls the heater to perform heating cooking based on the signals from the first and second sensors. It is designed to achieve the intended purpose.

(Example) The present invention shown in the drawings below? The actual manufacturing will be explained in detail.

First, FIG. 2 shows a schematic structure of the rice cooker of the present invention.

In the figure, 1 is the insulated main body of the jar rice cooker, 2 is the outer pot, and 3 is the rice cooker heater (700W) installed at the inner bottom of the outer pot 2.
, 4 is an inner pot that can be moved in and out of the outer pot 2 and accommodates the food to be cooked;
5 is a heat-retaining heater provided on the outer surface of the outer pot 2; 6 is a first sensor such as a Sami sensor that is in contact with the outer bottom surface of the inner pot 4 to detect temperature changes at the bottom; 7 is an outer lid having a heat-insulating structure; 8 is the outer lid 7
9 is a hollow hanging rod protruding from the center of the inner surface of the outer lid 7; 10 is an inner heater that is removably inserted and supported on the hanging rod 9 through a seal packing 11; Lid, 12
14 is a steam cylinder with a built-in pole valve 13 protruding from the inner lid 10;
is a second sensor such as a therminuta enclosed in the hanging rod 9, and this sensor 14 is connected to the inner pot 4 via the hanging rod 9.
Detects changes in the ambient temperature inside the device. Note that the hanging rod 9 is made of a metal with good thermal conductivity, such as aluminum.

Next, FIG. 3 is a diagram showing the operating section. 15 is a time display section, 16 is a menu select button, 17 is an hour set key, 18 is a minute set key, 19 is a start key, 20
21 is a cancel key, 21 is a warming start key, and a~ are display LEDs, and the display LEDa displays the timer operation. The display LED b indicates each step of preheating, rice cooking (1st), rice cooking (2nd), rice cooking (3rd), double cooking/uniform cooking, and keeping warm, and the display LED h- indicates white rice. , brown rice, cooked rice, and porridge menus are displayed. moreover,
The operation section is marked with a notification timing according to its positional relationship with the display LEDs b-g.

FIG. 4 is a block diagram of the entire control circuit. In FIG. 4, 22 is a microcomputer, which mainly includes a central processing unit (hereinafter referred to as CPU) 23 and an electronic timer 24.
, a read-only memory (hereinafter referred to as ROM) 25, an arbitrary access memory (hereinafter referred to as RAM) 26, and an interface (input/output signal processing circuit) 27. The ROM 25 stores a control program for the CPU 23, and the RAM 26 is used as a data memory for the CPU 23. The CPU 23 reads the status of each part on the input side via the interface 27 and also reads the control program in the ROM 25 to control preheating, rice cooking (primary) (secondary) (tertiary), and rice cooking.
It determines processes such as boiling, uneven cooking, and keeping warm, and controls the heating unit etc. necessary to execute the process via the interface 27, and the process transition is performed in cooperation with the electronic timer 24. It will be done. In addition, the electronic timer 24 is
3, it counts up or down the time and outputs a signal.

In the above configuration, the control will be explained in detail below. Incidentally, Fig. 5 is a model diagram showing the temporal change in the temperature detected by the first and second sensors, and Fig. 6 is a diagram showing the relationship between the temperature detected by the sensor and the rice cooking power as the capacity changes. .

First, after turning on the power, press the menu select button 16.
Select the desired menu. In accordance with this selection, a predetermined display LED is turned on and a menu is displayed.

white rice cooked rice Now, the case where cooked white rice is selected will be explained.

First, when the start key 19 is turned on after selecting the menu, the CPU 23 confirms that the start key 19 is turned on, and then determines which flag is designated. now,
Since white rice cooking has been selected, the designation of flag 1 is determined and the control program in the ROM 25 corresponding to flag 1 is read out to perform control as shown in the flowchart shown in FIG. Incidentally, when the nut key 19 is turned on, a notification section (for example, a piezoelectric buzzer) is activated to emit a confirmation sound.

O Preheating Step In this preheating step, the food to be cooked (rice and water) is heated up to a certain temperature, and the above temperature is maintained until a certain period of time has elapsed from the start of rice cooking (preheating). In addition, in Fig. 7, D
The frame indicated by indicates a flowchart of the preheating process.

When the preheating process starts, the rice cooking heater 3 is turned on and heats the object to be heated, and the heating is continued until the temperature detected by the first sensor 6 reaches a certain temperature (for example, 62° C.). When the detected temperature reaches 62° C., the rice cooking heater 3 is turned off. Thereafter, by turning on and off the rice cooking heater 3 based on the temperature detected by the first sensor 6, the temperature is maintained at 62°C until a certain period of time (for example, 10 minutes) has elapsed from the start of preheating, and when 10 minutes have passed, Move on to the next stage of rice cooking (first stage) process.

The purpose of this process is to promote water absorption of the rice, to correct the temperature of the food to be cooked against the initial water temperature and air temperature, and to make the temperature distribution uniform regardless of the amount of rice cooked. and time are just examples, and may be arbitrarily set to values necessary to achieve the intended purpose.

In the preheating process, the temperature detected by the second sensor 14 is lower than the temperature detected by the first sensor 6, as shown in FIG. 5, and the rising curve is extremely gradual.

0 Rice Cooking (Primary) Process In this process, capacity determination data is collected, the amount of rice to be cooked is determined based on this data, and the heating duty of the next stage is determined. In FIG. 7, the frame indicated by E shows a flowchart of the process.

Now, when moving to the rice cooking (first stage) process, turn the rice cooker heater 3 to O.
The detected temperature of the first sensor 6 becomes 6 by continuous heating with nitrogen.
While the food to be cooked is heated from 2° C. to a predetermined temperature (for example, 88° C.), the time from the start of the rice cooking process is counted up.

When it is determined that the temperature detected by the first sensor 6 has reached 88° C., the timer data T at this time is read and stored as data T1.

Next, the amount of cooked rice is determined based on this timer data T1,
Determine the heating duty for the next rice cooking (secondary) process.

Here, the determination of the amount of cooked rice will be explained. The amount of rice cooked is in 10 stages from 1 go (0,186) to 10 go (1,81), and each has its own unique time period for the temperature detected by the first sensor 6 to reach 88°C from 62°C. 1 depending on the time width
It is divided into 0 stages, and a heating duty is set for each rice cooking amount as described later, and the programmed contents are stored in advance in the ROM 26. For example, if the rice cooking heater 3 is 700W, the timer data T1 is 50W.
If it is 0 seconds or more, it is determined to be 10 cups, and if it is 1.50 seconds or less, it is determined to be 1 cup, and the period from 500 seconds to 150 seconds is divided according to the time width specific to each rice cooking amount. Thus, the amount of cooked rice is determined by sequentially subtracting the time width for each amount of cooked rice from the timer data T1, and determines the amount of cooked rice when the relationship T1<0 is reached.

Next, the heating duty is set corresponding to each amount of rice to be cooked, and is used to adjust the time during which the rice cooking heater 3 is energized within a certain period (for example, 64 seconds). This heating duty is intended to keep fluctuations in the execution time of the rice cooking (secondary) process due to the amount of rice cooked to a minimum.For example, in the case of 10 cups, electricity is applied to the rice cooking heater 3 at 64V for 64 seconds, and in the case of 1 cup, it is 32,544 seconds. During this time, the heating duty is set according to the amount of rice to be cooked. Therefore, the heating power in the rice cooking (secondary) step is 700 W for 10 cups and 350 W for 11 cups.

In the rice cooking (primary) process, the temperature detected by the second sensor 14 is low as shown in Figure 5, and the rising curve is gradual. The end temperature of the rice cooking (primary) step and the cycle of duty control are not limited to the above values.

0 After the rice cooking amount is determined and the heating duty is determined in the first step of the rice cooking (secondary) process, when the rice cooking (secondary) process is started, the rice cooking heater 3 is controlled in duty according to the above determination. While heating the food, the time is counted up following the previous step, and by determining whether the food has boiled, the process moves to the next rice cooking (tertiary) step.

In FIG. 7, the frame indicated by F shows a flowchart of the process.

Here, determination of boiling of the food to be cooked will be explained.

As shown in FIG. 5, the temperature detected by the first sensor 6 reaches 100°C in a short time from the start of the rice cooking (secondary) process, but this is due to the temperature at the bottom of the food near the rice cooking heater 3. This is due to partial boiling and the heat effect of the rice cooking heater 3, and at this point the entire food to be cooked has not yet reached a boiling state, so boiling is determined based on the temperature detected by the first sensor 6. It lacks accuracy. On the other hand, the temperature detected by the second sensor 14 gradually rises even after the start of the rice cooking (secondary) process, and the entire food to be cooked begins to boil and a lot of steam is generated, causing steam to flow inside the inner pot 4. When it starts to fill up, it rises rapidly.

Therefore, by detecting a sudden rise in the temperature detected by the second sensor 14, it is possible to accurately determine whether the entire food to be cooked has boiled.

However, when the temperature detected by the second sensor 14 suddenly rises, it is sensed that the temperature has reached a certain temperature (for example, 90° C.), and boiling is determined.

Therefore, the rice cooking (secondary) process ends when it is determined that the temperature detected by the second sensor 14 has reached 90 degrees Celsius, and the process moves to the next rice cooking (tertiary) process, while the timer data at this point T, that is, the elapsed time from the start of the rice cooking (primary) process to the end of the rice cooking (secondary) process is read and stored as data T2. Next, based on this timer data T2, the amount of rice to be cooked is determined in the same way as in the previous case, and the heating duty of the next stage is determined.

The amount of rice cooked is divided into 10 stages as in the previous case. For example, when the timer data T2 is 750 seconds or more, it is 10 cups, and when it is 350 seconds or less, it is 1 cup, and in between is a time width specific to each rice cooking amount. It is divided by. Also, heating duty
In order to completely gelatinize the rice, the rice cooking (tertiary) process should take at least 20 minutes including the cooking and scouring process twice, the rice should be cooked (1 The time from the start of the next) process to the end of the rice cooking (third) process is set for each amount of rice, with the condition that the time is approximately constant regardless of the amount of rice cooked.For example, in the case of 10 cups, the heating electric cuff 00
For 1 cup, set the heating power to 175W (16% rice cooking heater ON for 4 seconds).

O Rice Cooking (Tertiary) Process In this process, the rice to be cooked, that is, white rice, is cooked by duty-controlling the rice cooking heater 3 based on the above determination.

In FIG. 7, the frame indicated by G shows a flowchart of the process.

Immediately, heating progresses due to the duty control of the rice cooking heater 3, water in the inner pot 4 disappears, the bottom temperature rises rapidly, and the temperature detected by the first sensor 6 reaches the finished cooking temperature (for example, 124°C). When it is determined that the rice cooking heater 3 has reached 0FFL, the rice cooking heater 3 moves to the next twice-cooking/uniforming process.

In addition, since the heating duty in the rice cooking (tertiary) process is set based on the conditions mentioned above, the cooking time is almost the same regardless of the amount of rice cooked, as shown in Figure 6. That's it. Also, the notification section is activated when the rice is cooked.

02-degree cooking/uniform process This process finishes the rice by draining and browning the cooked rice, and by completing this process, sufficient unevenness is achieved and the rice is ready to eat.

In FIG. 7, the frame indicated by H shows a flowchart of the process.

When moving to the double-cooking/uniforming process, a countdown for a certain period of time (for example, 12 minutes) is started, while waiting for the temperature detected by the first sensor 6 to drop to a predetermined temperature (for example, 110°C), and then the temperature is increased to 110°C. When it is determined that the temperature has reached 124°C, turn on the rice cooking heater 3 and heat it again until it reaches 124°C.
When the temperature reaches 124° C., the rice cooking heater 3 is turned off and is kept in a stopped state. Then, after 12 minutes have elapsed, the completion of the rice is notified and the process moves on to the warming process.

O Heat retention process When moving to the heat retention process, the heat retention process shown in frame 1 in Figure 7,
The heat-retaining heaters 5 and 8 are controlled according to the temperatures detected by the first sensor 6 and the second sensor 14 to keep the rice at a warm temperature.

That is, if the temperature detected by the first sensor 6 decreases to, for example, 73° C. or lower, or if the temperature detected by the second sensor 14 decreases to, for example, 76° C. or lower, the heaters 5 and 8 are turned ONL,
When the temperature detected by both sensors 6, 14 exceeds the above temperature, the heat-retaining heaters 5 and 8 are turned off, and the temperature is kept warm by repeating this process thereafter.

Note that the set temperature of the second sensor 14 is the same as that of the first sensor 6.
The reason why the temperature is higher than the set temperature is to prevent dew from forming on the inner surface of the inner lid 10. Also, the reason why both the sensors 6 and 14 control the heat retaining heaters 5 and 8 is that the sensor 6 of @1
This is because the temperature drop in the upper part due to the opening of the lid cannot be quickly detected with only □, and the temperature change of the food to be cooked, that is, the rice, cannot be accurately detected with only the second sensor 14.

As described above, white rice is cooked.
Next, I will explain brown rice cooking.

When brown rice cooking is selected using the button 16 and the start key 19 is turned on, the designation of flag 2 is determined, and the corresponding control program is read out, as shown in the flowchart shown in Figure 8. Control. In addition, in Fig. 8, the parts common to Fig. 7 are
Reference numerals are given to the frames in the figure, and details are omitted.

The control of this brown rice cooking is basically the same as that of white rice cooking, and only the different points will be explained below.

In the preheating process for cooking brown rice, the execution time is set longer than that for cooking white rice, so that even brown rice, which has poor water absorption compared to white rice, can absorb sufficient water. - As an example, for the 10 minute preheating process of white rice cooking,
Set □ to 30 minutes. Each process of rice cooking (1st) (2nd) (3rd), 2-time cooking/uniform cooking, and □ keeping warm after the preheating process is controlled in the same way as when cooking white rice. However, the reference time and heating duty for capacity determination are set to specific values based on experimental data for cooking brown rice.

For example, in the rice cooking (primary) process, timer data T1 is 4.
When the time is 00 seconds or more, it is determined as 10 cups, and when it is 140 seconds or less, it is determined as 1 cup. Also, in the rice cooking (secondary) process, timer data T2 is 1.
000 seconds or more, it is judged as 10 cases, and when it is 650 seconds or less, it is judged as 1 case.

On the other hand, the heating duty for the rice cooking (secondary) process is 60 seconds for 14 seconds at 10 cups, and the rice cooking heater is turned on (heating power 656 W).
For 1 cup, turn on the rice cooking heater for 32 to 44 seconds (heating power 350
W) and the heating duty of the rice cooking (tertiary) process.
For 10 cups, the rice cooking heater is set to ON for 58 Y 4 seconds (heating power 634 W), and for 1 cup, the rice cooking heater is set to ON for 16 Y 4 seconds (heating power 175 W), so the boiling period is slightly longer than when cooking white rice. It is set as follows.

When the rice cooking menu button 16 is used to select rice cooking and the start key 19 is turned on, the designation of the flag 3 is determined, and the corresponding control program is read out, so that the flowchart shown in FIG. 9 is executed. Control as follows. In FIG. 9, the parts common to those in FIG. 7 are designated by the symbols in the frame in FIG. 7, and the details are omitted.

The steps of preheating, cooking (primary) (secondary), cooking twice/uniformly, and keeping warm are basically the same as for white rice cooking, and the different cooking (tertiary) steps are explained below. .

Some of the ingredients for cooked rice are added from the beginning of cooking, and others are added when the rice boils, so a boiling alarm is set in the rice cooking (tertiary) process so that the addition of ingredients can be detected. .

First, when moving to the rice cooking (tertiary) step, the alarm unit is sounded to notify boiling and prompt the addition of ingredients. After that, if no ingredients are added, cooking is performed by duty-controlling the rice cooking heater 3 according to the heating duty determined in the rice cooking (secondary) process, and the temperature detected by the first sensor 6 is 124. When the temperature reaches ℃, move on to the next step.

On the other hand, when the lid is opened and the ingredients are added, the temperature detected by the second sensor 14 drops rapidly due to the inflow of outside air, as shown in FIG. When the determination is made, the rice cooking heater 3 is turned on continuously,
Regardless of the heating duty, by heating with the heating electric cuff 00W, the temperature detected by the second sensor 14 is 90°C.
Raise the temperature in a short period of time until When it is determined that the temperature detected by the second sensor 14 has reached 90°C, the rice cooking heater 3 is thereafter duty-controlled until the temperature detected by the first sensor 6 reaches 124°C. It turns out.

Note that the reference time and heating duty for capacity determination are set to specific values based on experimental data. For example, in the rice cooking (primary) process, when timer data T1 is 650 seconds or more, 10
If the time is 250 seconds or less, it is judged as 1 cup, and the rice is cooked (secondary).
In the process, when the timer data T2 is 800 seconds or more, it is judged as 10 cases, and when it is 400 seconds or less, it is judged as 1 case. The heating duty for the rice cooking (secondary) process is set to 64 seconds for 10 cups (heating power cuff 00W), and 32 seconds for 1 cup to turn on the rice cooker heater (heating power 350W). The heating duty of the rice cooking (tertiary) process is 60% at 10 cups.
4 seconds rice cooking heater ON (heating power 656W), 1 cup +
5 seconds Set the rice cooker heater ON (heating power 164W) for 4 seconds.

When porridge cooking is selected using the porridge cooking menu select button 16 and the Nutato key 19'e is turned on, the designation of flag 4 is determined and the corresponding control program is read out, thereby controlling as shown in the flowchart of FIG. 11. . In FIG. 11, the parts common to those in FIG. 7 are designated by the reference numerals in the frame in FIG. 7, and the details are omitted.

The preheating, rice cooking (primary) (secondary) steps of porridge cooking are basically the same as those for white rice cooking, and the different rice cooking (tertiary) and twice-cooking/shading steps will be explained. Note that no heat-keeping step is provided in cooking the porridge.

In porridge cooking, the elapsed time from the start of cooking is counted, and the rice cooking (tertiary) step shifts to the next step, the shading step, when a certain period of time (for example, 60 minutes) has elapsed from the start of cooking. The unevenness process ends when the rice cooking heater 3 is turned off and a certain period of time (for example, 5 minutes) has elapsed.

Note that the reference time and heating duty for capacity determination are set to specific values based on experimental data. For example, in the rice cooking (primary) process, when timer data T1 is 700 seconds or more, 10
If the time is 350 seconds or less, it is determined as 1 cup, and in the rice cooking (secondary) process, if the timer data T2 is 900 seconds or more, it is determined as 10.
If it is 500 seconds or less, it is determined as 1 match. On the other hand, the heating duty of the rice cooking (secondary) process is 32.1 when the rice is 10 cups.
4 seconds rice cooking heater ON (heating power 350W), 1 cup
Set the rice cooker ON (heating power 175W) for 6 rye and 4 seconds, and the heating duty for the rice cooking (tertiary) process is 16〉a. Second rice cooking heater ON (heating power 175W),
When cooking 1 cup, turn on the rice cooker heater for 4 seconds (heating power: 131
When the rice is set to W), especially in the rice cooking (tertiary) process, the heating power is set to the minimum that can maintain boiling to prevent boiling.

As described above, in this embodiment, the first and second sensors 6.
By controlling the rice cooking heater 3 based on a signal from the rice cooker 14, various kinds of cooking such as white rice cooking, brown rice cooking, etc. are performed. In addition, in various types of cooking, the time from the start of preheating to the end of double cooking and shading is controlled so that it is approximately constant regardless of the capacity, but this is disclosed in Japanese Patent Application Laid-Open No. 59-232.
This is to make it possible to implement the rice finishing timer as shown in Japanese Patent No. 520 and the like.

In the above embodiment, the amount of cooked rice is determined twice using the same method, but the method of determination is not limited to the above method.
The method disclosed in Japanese Patent No. 232520 or the like may be adopted. In this method, while raising the food to be cooked from a certain temperature to a certain temperature, the set temperature is gradually increased in small increments, the ON time of the rice cooking heater is accumulated during this time, and the capacity is determined by the cumulative ON time of the rice cooking heater. This method uses the data as data and determines the amount of cooked rice based on this data. Therefore, such a method can be adopted not only for the first determination but also for the second determination in the case of white rice cooking which does not particularly require boiling detection.

Further, the second sensor 14 is not limited to the position in the above embodiment, but may be in any position as long as it can detect changes in the ambient temperature due to cooking.

However, it is desirable to thermally isolate it from the heat-retaining heater.

In addition, the present invention can be implemented with appropriate modifications within the scope of the invention.

(Effects of the Invention) As described above, according to the cooking device of the present invention, it is possible to accurately detect the completion of rice cooking, boiling, etc., and it is also possible to cook brown rice, cooked rice, tokayu, etc. in good condition.

[Brief explanation of drawings]

FIG. 1 is a diagram showing the configuration of the present invention, FIG. 2 is a schematic structural diagram of a jar rice cooker in an embodiment of the present invention, FIG. Block diagram, Figure 5 is a model showing the temporal change in the temperature detected by the above sensor, Figure 6 is a diagram showing the relationship between the temperature detected by the sensor and the rice cooking power as the capacity changes, and Figure 7 is 8 is a flowchart for cooking brown rice as above, FIG. 9 is a flowchart for cooking rice with mixed rice as above, and FIG. 10 shows a model of the change in temperature detected by the second sensor in cooking rice as above. FIG. 11 is a flowchart of cooking the same porridge as above. 3: Rice cooking heater, 4: Inner pot, 6: First sensor,
14: second sensor, 22: microcomputer. Agent Patent Attorney Aihiko Fuku (and 2 others) Team I o1

Claims (1)

[Claims] 1. A pot that accommodates the food to be cooked, a heater that heats the pot to cook the food, a first sensor that detects temperature changes at the bottom of the pot, and a sensor that detects changes in the temperature of the atmosphere during cooking. A cooking appliance comprising: a second sensor that detects a change; and a control means that controls the heater to perform heating cooking based on signals from the first and second sensors.