JPS61222421A - 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, porridge, and the like.

(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, porridge, etc. It was not very desirable for cooking.

In other words, the sensor installed at the bottom of the pot can obtain good results in detecting the completion of rice cooking and detecting the temperature in the low temperature range, but the sensor installed near the rice cooker is greatly affected by the heat9. Also, since it is greatly affected by the uneven temperature distribution of the food to be cooked, it is difficult to obtain very favorable results for detecting boiling of the food to be cooked.On the other hand, it is not ideal for cooking brown rice, porridge, etc. However, conventional rice cookers such as those mentioned above cannot accurately detect boiling, and therefore cannot cook brown rice, porridge, etc. in good condition. It was decided that it would not be possible to do so.

(Purpose of the Invention) The present invention has been made in view of the above points, and is suitable for accurately detecting boiling when cooking brown rice, porridge, etc., which requires detecting the boiling of the food to be cooked and adjusting the heating power. By doing so, it is possible to provide a cooking device that allows cooking to be carried out in good condition.

(Structure of the Invention) The present invention provides a cooker that detects the boiling of the food to be cooked and adjusts the heating power. It is configured to perform detection and achieve the intended purpose.

(Example) Examples of the present invention shown in the drawings will be described in detail below.

First, FIG. 1 shows the 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 thermistor 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 a 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 ball valve 13 protruding from the inner lid 10;
is a second sensor such as a thermistor sealed in the hanging rod 9, and this sensor 14 detects a change in the atmospheric temperature inside the inner pot 4 via the hanging rod 9. Note that the hanging rod 9 is made of a metal with good thermal conductivity, such as aluminum.

Next, FIG. 2 is a diagram showing the operating section. ]5 is the time display section, 16 is the menu select button, 17 is the hour set key, 18 is the minute set key, ]9 is the 7 start key, 20
2] is a cancel key, 2] is a warming start key, a=k is a display LED, and the display LEDa indicates the timer operation. The display LEDs b to g display 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- displays white rice, Displays menus for brown rice, cooked rice, and porridge. Furthermore, the operating section is marked with a notification timing based on its positional relationship with the display LEDs b-g.

FIG. 3 is a block diagram of the entire control circuit. In FIG. 3, 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
It counts up or down the time according to instructions from 23 and outputs a signal.

In the above configuration, the control will be explained in detail below. In addition, Fig. 4 is a diagram showing a model of the temporal change in the temperature detected by the first and second sensors, and Fig. 5 is a diagram showing the relationship between the temperature detected by the sensor and the rice cooking power as the capacity changes. .

First, turn on the power, then press menu select button 1.
6 to select the desired menu. In accordance with this selection, a predetermined display LED'lr lights up 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 ]9 is turned on, and then determines which flag is designated. now,
Since white rice cooking has been selected, the designation of the flag 1 is determined and the control program in the ROM 25 corresponding to this flag 1 is read out to perform control as shown in the flowchart shown in FIG. Incidentally, when the start key 19 is turned on, a notification section (for example, a piezoelectric buzzer) is activated to emit a confirmation sound.

0 Preheating step In this preheating step, the food to be cooked (rice and water) is heated 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. 6, 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.

This process is carried out for the purpose of promoting water absorption of rice, correcting the temperature of the food to be cooked against the initial water temperature and air temperature, and making the temperature distribution uniform regardless of the amount of rice cooked. The temperature 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. 4, 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. 6, 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 steps from 1 go (0,]8#) to 10 go (1,81), and the time required for the temperature detected by the first sensor 6 to reach 88°C from 62°C is determined respectively. 1 due to the unique 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 Tl is 50W.
When it is 0 seconds or more, it is judged as 10 go, and when it is 150 seconds or less, it is judged as 1 go.
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, it is 64 seconds, and in the case of 1 cup, it is 82 seconds. During this time, the heating duty is set according to the amount of rice to be cooked. Therefore, cooked rice (
The heating power for the second step is 700 W for 10 cups and 350 W for 1 cup.

In addition, in the rice cooking (primary) process, the temperature detected by the second sensor 14 is low as shown in FIG. 4, and the rising curve is also gradual. The end temperature of the rice cooking (primary) step and the cycle of duty control are not limited to the above values.

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

In FIG. 6, 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. 4, 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 thermal influence 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 rice cooking (secondary) process starts, and the entire food to be cooked starts to boil, and steam is actively generated, causing steam to flow inside the inner pot 4. As it begins to fill up, it rises rapidly.

Therefore, by detecting the rapid rise in the temperature detected by the second sensor [4], 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 manner as in the previous case, and the heating duty of the next stage is determined.

As in the previous case, the amount of rice cooked is divided into 0 stages.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. It is divided by width. Also, heating duty
In order to completely gelatinize the rice, the rice cooking (tertiary) process should be cooked twice and the time for the shading process should be at least 20 minutes, there should be no boiling over, and the rice cooking (first) should be over 20 minutes. The time from the start of the process to the end of the rice cooking (tertiary) process is set for each rice cooking amount, with the condition that the time from the start of the process to the end of the rice cooking (tertiary) process is approximately constant regardless of the rice cooking amount.
W (64 minutes, 14 seconds), rice cooking heater ON), heating power for 1 cup] Set to 75 W (16 minutes, 14 seconds, rice cooking heater ON).

0 Rice Cooking (Third) Step In this step, 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. 6, the frame indicated by G shows a flowchart of the process.

RD Ji, heating progresses through 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 you determine that you have reached
The rice cooking heater 3 is set to 0FFL and the rice is moved 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 time for rice to finish cooking should be approximately the same regardless of the amount of rice to be cooked, as shown in Figure 6. become. Father activates the alarm 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. 6, 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, as shown by the frame I in Figure 6,
The heat-retaining heaters 5 and 8 are controlled in accordance with 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-mentioned temperature, the heat-retaining heater 5.8 is turned off, and the temperature is kept warm by repeating this process from now on.

Note that the set temperature of the second sensor 14 is the same as that of the first sensor 6.
The reason for raising the set temperature is to prevent dew from forming on the inner surface of the inner lid. Also, the reason why the heat retention heaters 5 and 8 are controlled by both sensors 6 and 14 is that the first sensor 6.
This is because the second sensor I4 alone cannot quickly detect the temperature drop in the upper part due to opening of the lid, and the second sensor I4 alone cannot accurately detect the temperature change of the food to be cooked, that is, the rice.

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

When brown rice cooking is selected using the brown rice cooking menu select 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, thereby controlling as shown in the flowchart shown in Figure 7. do.

In FIG. 7, the parts common to those in FIG. 6 are designated by the reference numerals in the frame in FIG. 6, and the 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 it to 30 minutes. Cooking rice after preheating process (1st) (2nd)
(Third stage), twice-cooking, uneven cooking, and keeping warm are 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 of the rice cooking (secondary) process is 60>44 seconds at 10 cups, rice cooking heater ON (heating power 656W),
When cooking 1 cup, turn on the rice cooker heater for 4 seconds (heating power 350
W) and the heating duty of the rice cooking (tertiary) process.
When it is 10 cups, it is 58y and 64 seconds, and the rice cooking heater is turned on (heating power is 634W), and when it is 1 cup, it is 16>44 seconds.
The heating power is set to 175 W), and the boiling period is set to be slightly longer than when cooking white rice. This is to ensure that even hard brown rice is cooked to its core.

When υ cooked rice is selected using the cooked rice menu selection button 16 and the start key 19 is turned on, the designation of flag 3 is determined and the corresponding control program is read out, as shown in the flowchart shown in Figure 8. Control. In FIG. 8, the parts common to those in FIG. 6 are designated by the reference numerals in the frame in FIG. 6, 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 takikomi rice are added at the beginning of the cooking process, while others are added when the rice boils. Therefore, a boiling alarm is set during the rice cooking (third stage) process so that the addition of ingredients can be detected. be.

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 When the temperature reaches 124°C, proceed to the next step.

On the other hand, when the lid was opened and the ingredients were put in, the temperature detected by the second sensor 14 suddenly decreased due to the inflow of outside air, as shown in the third example, and the detected temperature decreased to 90°C or less. When it is determined, the rice cooking heater 3 is turned on continuously,
Regardless of the heating duty, the temperature detected by the second sensor 14 is 90°C by heating with the heating electric cuff 00W.
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. Become.

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 the timer delay 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. Also, the heating duty for the rice cooking (secondary) process is set to 64 seconds for 10 cups (heating power cuff 00W), 32 seconds for 1 cup (heating power 9 ONC heating power 350W)). , Cooked rice (
The heating duty of the 3rd) process is 60shi4 at 10go
Second rice cooking heater ON (heating power 656W), 15 minutes for 1 cup
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 Nutatoki=19 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. 10. . In FIG. 10, the parts common to those in FIG. 6 are designated by the reference numerals in the frame in FIG. 6, and the details are omitted.

The preheating, rice cooking (first) (secondary) steps of porridge cooking are basically the same as those for white rice cooking, but the different cooking (third), twice-cooking, and 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 moves to the next stage of scouring 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 judged as 1 go, and in the rice cooking (secondary) process, if the timer temperature T2 is 900 seconds or more, it is judged as 1 go.
When the time is 0 and 500 seconds or less, it is determined as 1. On the other hand, the heating duty in the rice cooking (secondary) process is 32% at 10 cups.
4 seconds rice cooking heater ON (heating power 350W), 1 cup
Set the rice cooking heater ON for 44 seconds (heating power 175W) for 6 boats, and the heating duty for the rice cooking (tertiary) process is 16>44 seconds when the rice cooking (tertiary) process is 10 cups.
For 1 cup, turn on the rice cooker heater for 12% seconds (heating power 131W)
Particularly in the rice cooking (tertiary) process, the heating power is set to the minimum required to maintain boiling to prevent boiling over.

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 and brown rice cooking 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 enable implementation of 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. In this method, the amount of cooked rice is determined 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 a change in ambient temperature due to cooking and detect boiling. for example,
As shown in FIG. 11, a second sensor 14 protected by a heat-resistant insulating tube 28 is disposed inside the steam cylinder insertion part 7a of the outer cover 7, and the second sensor 14 is connected to the steam cylinder]2.
Boiling may be detected based on the temperature of ejected steam by locating the end openings of the two to face each other. Further, for a cooking device in which steam is temporarily released into the space between the inner surface plate of the outer lid 7 and the inner lid 10, and then released outward, the structure shown in FIG. 12 may be adopted. In the structure shown in FIG. 12, a heat-sensitive case 29 is provided on the inner surface plate 7b of the outer cover 7, and a second sensor 1 is installed inside the case 29.
4 is arranged, and the outer cover 7 and the inner cover 10 are detected by this sensor 14.
This structure detects boiling by detecting the atmospheric temperature of the space between the two. Reference numeral 30 denotes a thermal insulator interposed between the inner surface plate 7b and the heat-sensitive case 29 to prevent thermal influence on the second sensor 14 of the heat-retaining heater 8.

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 configuration of the present invention, boiling of the food to be cooked can be accurately detected, and good conditions can be maintained even when cooking brown rice, porridge, etc., where boiling detection is important. It can be done with

[Brief explanation of the drawing]

Fig. 1 is a schematic structural diagram of a jar rice cooker according to an embodiment of the present invention, Fig. 2 is a diagram showing the operating section of the above, Fig. 3 is a block diagram of the entire control circuit of the above, and Fig. 4 is a temperature detected by the sensor of the above. Fig. 5 is a diagram showing the relationship between the temperature detected by the sensor and the rice cooking power as the capacity changes, Fig. 6 is a flowchart for cooking white rice, Fig. 7
The figure is a flowchart for brown rice cooking as above, Figure 8 is a flowchart for boiling rice as above, Figure 9 is a model showing the change in temperature detected by the second sensor in cooking rice as above, and Figure 10 is porridge cooking as above. The flowchart of FIG. 11 and FIG. 12 are diagrams showing other examples of arrangement of the second sensor same as above. 3: Rice cooking heater, 4: Inner pot, 6: First sensor,
14: second sensor, 22: microcomputer. Agent Patent attorney Aihiko Fukushi (and 2 others) 99C ¥//Figure 7Q- Figure 72

Claims (1)

[Claims] 1. A device that detects the boiling of the food to be cooked and adjusts the heating power, characterized in that it is equipped with a sensor that detects changes in the ambient temperature accompanying the cooking of the food, and the boiling is detected by this sensor. Cooking device.