JP2000262400A - Rice cooker - Google Patents

Abstract

PROBLEM TO BE SOLVED: To restrict boiling-over regardless of the quality of rice and to excellently cook rice without a non-uniformity in cooking by executing hot fire heating for a hot fire extension time which is set by means of a hot fire extension time setting means after detecting boiling through the use of a boiling detecting means and, then, executing low flame heating. SOLUTION: In a rice cooking operation, an induction coil is controlled to permit the detecting temp. of a pot temp. detecting means 23 to be fixed to be 55 deg.C in a pre-heating process to promote water absorption in rice. The pre-heating process is executed for 15 minutes and the process is shifted to the hot fire one after 15 minutes elapses. The induction coil is turned-on by 100% in the hot fire process, the boiling of cooked rice in a pot is waited and boiling is judged at the point of time when the detecting temp. of a lid temp. sensor 6 becomes 90 deg.C or more concerning boiling detection. When boiling is detected, the hot fire extension time setting means 19 selects a hot fire extension time by a hot fire extension time storage means 25 based on the setting of a rice quality selecting means 18 and a flow flame energizing time setting means 27 selects and sets a low flame energizing time by a low flame energizing time storage means 26 based on the setting of the means 18.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a rice cooker for controlling an input to a heating means to cook rice.

[0002]

FIG. 19 is a sectional view of a conventional rice cooker.
1 is a rice cooker body with an open top, 2 is a pot accommodated in the rice cooker body 1, 3 is an induction coil provided in the rice cooker body 1 and heats the pot 2, and 4 is an open / close upper opening of the body 1. A lid 6 for freely covering the lid 4, a lid temperature sensor provided on a surface of the lid 4 facing the pot 2, an operation panel 7 provided on the front surface of the rice cooker main body 1, and a pan 8 provided in the rice cooker main body 1. A pot temperature sensor 5c for detecting the temperature of the pot 2 by contacting the bottom of the pot 2 is a steam port provided in the lid 4.

In a conventional rice cooker, the amount of heating is adjusted by electronically controlling the energization of the induction coil 3 so that the quality of rice such as new rice, standard rice, old rice, old rice, foreign rice, hard rice, and soft rice is obtained. Some rice cookers control rice cooking according to the conditions. FIG. 20 shows an operation panel 7 of such a rice cooker, 9 is a rice quality selection key for selecting rice quality, 10 is a display for displaying the current time and rice quality settings, and 11 is rice cooker. A start key 12 for starting operation is a cut-off key for canceling the setting and stopping the operation. Hour key 14, minute key 1
5 is performed.

FIG. 21 is a block diagram showing the entire configuration of a conventional rice cooker. Reference numeral 11 denotes a start key provided on the operation panel 7 for starting rice cooking, and 16 denotes a lid temperature sensor 6.
Cover temperature detecting means for detecting the temperature of the lid 4 based on the output of the lid, 17 a boiling detecting means for detecting the boiling of cooked rice based on the detected temperature of the lid temperature detecting means 16, and 20 comprising a microcomputer for controlling the operation of the whole rice cooker Is a heating means, which drives the induction coil 3 based on the output of the control means 20 to heat the pot 2. 23 is a pot temperature sensor 8
Is a pan temperature detecting means for detecting the temperature of the pan 2 based on the output of. 9 is a rice quality selection key for selecting rice quality, 18
Is rice quality selecting means for selecting and setting rice quality by inputting the rice quality selection key 9. Reference numeral 26 denotes a low heat energization time storage unit that stores energization time data of the induction coil 3 in the low heat process of cooking rice, and outputs the low heat energization time data based on the setting of the rice quality selection unit 18 to the low heat energization time setting unit 27. The low heat conduction time setting means 27 sets the low heat conduction time based on the output of the low heat conduction time storage means 26 and outputs it to the control means 20.

[0005] Rice starch is beta starch as raw and does not withstand the taste. However, by converting this starch into alpha, delicious and digestible rice is cooked. The pregelatinization conditions require sufficient moisture and heating at 96 ° C. or more for about 20 to 25 minutes.

[0006] By the way, depending on whether the rice to be cooked is new rice, standard rice, old rice, old rice, foreign rice, hard rice or soft rice, the water absorption rate of rice after rice cooking and the rate of starch pregelatinization differ. . In old rice, lipids on the surface are oxidized and a hard oxide film is formed on the surface, and therefore, there is a property that moisture is less absorbed in cooking rice compared to fresh rice. In old rice, the tendency is even stronger. In addition, the starch of hard rice is less likely to be converted to alpha than soft rice, so that moisture is also less likely to be absorbed. Furthermore, foreign rice generally has less water absorption than or equal to old or old rice, although there are differences depending on the place of production, the type of rice, and the state of storage.

[0007] When rice is cooked, the cooked rice may be hardened or softened by adjusting the time of the cooked rice, in particular, the time until the cooked rice is completed after the pot is boiled. it can. Therefore, old rice, old rice,
In the case of foreign rice or hard rice, if the amount of heating per unit time is reduced and the time from boiling to the end of rice cooking is adjusted longer, good cooking can be expected, like fresh rice or soft rice. In such a case, if the amount of heating per unit time is increased and the time from boiling to the end of rice cooking is adjusted to be short, good cooking can be expected in this case as well.

FIGS. 22 and 23 are flow charts for explaining the operation of such a conventional rice cooker. 24 to 28 are diagrams showing heating patterns of the rice cooker. FIG. 24 shows a heating pattern for fresh rice, FIG. 25 shows a heating pattern for standard rice, FIG. 26 shows a heating pattern for old rice, and FIG. FIG. 28 shows the heating pattern of foreign rice.

The operation of the conventional rice cooker will be described with reference to FIGS. When the control is started (S71), the rice quality setting is first set to "standard" (S72), and then the input of the rice quality selection key 9 is determined (S73), and the input of the rice quality selection key 9 is performed. If there is, the setting is changed (S74).
To S82). If the rice quality setting is "new rice" (S
74), the rice quality setting is changed to "standard" (S75), and if the rice quality setting is "standard" (S76), the rice quality setting is changed to "old rice"(S77); If the rice quality setting is “old rice” (S78), the rice quality setting is changed to “old rice” (S79), and if the rice quality setting is “old rice” ( (S80), the rice quality setting is changed to "foreign rice" (S81). If neither (foreign rice), (S80), the rice quality setting is changed to "new rice" (S82). ). That is, every time the rice quality selection key 9 is pressed, the setting of the rice quality is changed to “new rice” → “standard” → “old rice” → “old rice” → “foreign rice” → “new rice”. On the other hand, when the input of the rice quality selection key 9 is not performed (S73), the input determination of the start key 11 is performed (S83). When the input of the start key 11 is not performed, the input determination of the rice quality selection key 9 is performed. Returning (S73), the setting of rice quality is repeated. When the start key 11 is input (S8
3) Cooking rice is performed.

In the rice cooking operation, first, a preheating step is performed (S84). In the preheating step, as shown in FIG. 24, the induction coil 3 is controlled to be ON / OFF so that the detected temperature of the pot temperature detecting means is kept constant at 55 ° C. to promote the water absorption of rice. This preheating step is performed for 15 minutes, and after the elapse of 15 minutes, the preheating step is completed, and the process proceeds to the next high heat step (S85).

In the high heat process, first, the induction coil 3 is set to 100
% ON (S86), and waits for the cooked rice in the pot 2 to boil (S87). This boiling detection is performed by judging that the boiling point occurs when the temperature detected by the lid temperature sensor 6 becomes 90 ° C. or higher. When the boiling is detected, the low heat conduction time setting means 27 selects and sets the low heat conduction time TY from the low heat conduction time storage means 26 based on the setting of the rice quality selection means 18 (S88 to S96). If the setting of the rice quality selecting means 18 is “new rice” (S88), the low heat conduction time TY is set to 50.
Second (S89), and in the case of "standard" (S90),
The low heat conduction time TY is set to 40 seconds (S91). In the case of "old rice" (S92), the low heat conduction time TY is set to 30 seconds (S93). In the case of "old rice" (S94), The low heat conduction time TY is set to 20 seconds (S95). If neither (for foreign rice) (S94), the low heat conduction time TY is set to 10 seconds (S96). Then, it shifts to a low heat process (S97).

In the low heat process, the timer T2 of the control means 20 for counting the energization time to the induction coil 3 is started (S98), and the count of the timer T2 is compared with the low heat energization time TY (S99). When the count of the timer T2 is equal to or less than the low heat conduction time TY, the power supply to the induction coil 3 is turned on (S100). When the count of the timer T2 exceeds the low heat conduction time TY, the count of the timer T2 is 60 seconds. If less than (S101), the power supply to the induction coil 3 is turned off (S102), and if the count of the timer T2 is 60 seconds or more (S101), the timer T2 is restarted (S98). As a result, the induction coil 3 is repeatedly turned on for the set low heat conduction time TY and turned off for a time obtained by subtracting the low heat conduction time TY from 60 seconds, thereby performing low heat heating.

During boiling, the glue separated from the surface of the rice melts into the water, so that the free water in the pot 2 becomes a high viscosity rice cake and forms bubbles together with the steam generated at the bottom of the pot 2. The pot 2 is filled and spilled from the steam port 5c. In order to prevent this spill, in a conventional rice cooker, the heating operation is performed with a low heat to such an extent that the spill does not occur while maintaining boiling.

During this low heat process, the free water in the pot 2 is absorbed by the rice or evaporated and disappears, and the bottom temperature of the pot 2 starts to rise rapidly. When it is detected that the temperature has become equal to or higher than 120 ° C. (S103), the low heat process is terminated, and the process proceeds to the steaming process (S104). In the steaming process, maintaining the rice at a high temperature for 15 minutes further promotes the gelatinization of the rice, and evaporates excess water to cook delicious rice. The rice cooking operation ends with this steaming step (S105).

[0015]

In the conventional rice cooker, after detecting the boiling in this way, the amount of heating is immediately reduced to perform low heat heating, so that the rice cooker can be cooked while suppressing spillover. Immediately afterwards, the amount of heating is reduced,
Depending on the portion of cooked rice in the pot, there is a portion where the boiling temperature has not been sufficiently reached, resulting in a problem that the temperature is uneven and cooked rice cannot be cooked uniformly. In particular, this problem is remarkable in the case of old rice, old rice, foreign rice and hard rice.

The present invention has been made to solve such a problem, and regardless of the quality of rice such as new rice, standard rice, old rice, old rice, foreign rice, hard rice, and soft rice,
It is an object of the present invention to provide a rice cooker that can cook delicious rice with less unevenness and without uneven cooking.

[0017]

Means for Solving the Problems A rice cooker according to the present invention comprises a pot stored in a rice cooker main body, a heating means for heating the pan, a lid covering an upper opening of the rice cooker main body, The provided spill prevention means, the boiling detection means for detecting the boiling of the cooked rice in the pot, the rice quality selecting means for selecting the quality of the rice to be cooked when cooking rice, the rice quality selection A high-fire extension time setting means for setting the high-fire extension time based on the selection of the means, and after the boiling detection by the boiling detection means, high-heat heating for the high-fire extension time set by the high-fire extension time setting means is performed, Heating is performed.

Further, the heating amount of the high heat heating after the boiling detection by the boiling detecting means is set to 90% or more of the heating amount before the boiling.

A lid temperature detector is provided inside the lid,
Boiling is detected based on the temperature detected by the lid temperature detector.

Further, a pan temperature detector for detecting the temperature of the pan is provided, and it is determined that the boiling point occurs a predetermined time after the pan temperature detector detects a predetermined temperature.

[0021]

DESCRIPTION OF THE PREFERRED EMBODIMENTS Embodiment 1 FIG. 1 is a cross-sectional view of a rice cooker according to a first embodiment of the present invention. Reference numeral 1 denotes a rice cooker main body having an open top, reference numeral 2 denotes a pot stored in the rice cooker main body 1, and reference numeral 3 denotes a rice cooker main body. Induction coil for heating the pot 2
Reference numeral 4 denotes a lid for opening and closing the upper opening of the rice cooker main body 1;
Is a spillover prevention device provided on the lid 4. The spillover prevention device 5 is an introduction cylinder 5a that communicates into the pan 2 with the spillage and steam generated by an increase in the internal pressure of the pan 2 when boiling in the rice cooking process. The steam is separated from the steam and the steam by a plurality of barriers 5b on the way, and only steam is discharged from a steam port 5c opened to the outside of the lid 4 and the steam left from the steam port 5c.
When the boiling is stopped and the internal pressure of the pan 2 is reduced, the squirt is returned from the return valve 5e into the pan 2 to prevent the spill. Reference numeral 6 denotes a lid temperature sensor provided on the surface of the lid 4 facing the pot 2, reference numeral 7 denotes an operation panel provided on the front surface of the rice cooker main body 1, and reference numeral 8 denotes a cover provided in the rice cooker main body 1 and contacts the bottom of the pan 2. And a pan temperature sensor for detecting the temperature of the pan 2.
The configuration of the operation panel 7 is the same as that of the conventional one shown in FIG.

FIG. 2 is a block diagram showing the overall configuration of the rice cooker. Reference numeral 16 denotes a lid temperature detecting means for detecting the temperature of the lid 4 based on a signal from the lid temperature sensor 6, and reference numeral 17 denotes a temperature detected by the lid temperature detecting means 16. Means for detecting the boiling of cooked rice, 19 is a high heat extension time setting means for setting a prolonged high heat time after boiling, 20 is a control means comprising a microcomputer for controlling the whole operation, and 22 is a heating means. Means 2
Based on the output of 0, the induction coil 3 is driven to heat the pot 2. Reference numeral 23 denotes a pan temperature detecting means for detecting the temperature of the pan 2 based on a signal from the pan temperature sensor 8.

Reference numeral 9 denotes a rice quality selection key for selecting rice quality. Reference numeral 18 denotes rice quality selection means for selecting and setting rice quality by inputting the rice quality selection key 9. Reference numeral 25 denotes high heat extension time storage means which stores high heat extension time data corresponding to rice quality setting, and outputs high heat extension time data based on the setting of the rice quality selection means 18 to the high heat extension time setting means 19. . The high heat extension time setting means 19 sets the high heat extension time based on the output of the high heat extension time storage means 25,
Output to

Reference numeral 26 denotes a low heat energizing time storage means which stores energizing time data of the induction coil 3 in the low heat process, and outputs low heat energizing time data based on the setting of the rice quality selecting means 18 to the low heat energizing time setting means 27. I do. The low heat conduction time setting means 27 sets the low heat conduction time based on the output of the low heat conduction time storage means 26 and outputs the same to the control means 20.

Next, Embodiment 1 will be described with reference to FIGS.
The operation of the rice cooker will be described. FIGS. 3 and 4 are flow charts showing the operation of the rice cooker, FIGS. 5 to 9 are diagrams showing heating patterns of the rice cooker, FIG. 5 is a heating pattern of fresh rice, FIG. 6 is a heating pattern of standard rice, 7 shows a heating pattern for old rice, FIG. 8 shows a heating pattern for old rice, and FIG. 9 shows a heating pattern for foreign rice.

When the control is started (S1), first, the rice quality setting is set to "standard" (S2), and then the input of the rice quality selection key 9 is determined (S3). If there is an input of 9, the setting is changed (S4 to S12).
If the rice quality setting is "new rice" (S4), the rice quality setting is changed to "standard" (S5), and if the rice quality setting is "standard" (S6), the rice The quality setting is changed to "old rice" (S7). If the rice quality setting is "old rice" (S8), the rice quality setting is changed to "old rice" (S9).
If the rice quality setting is "old rice" (S10), the rice quality setting is changed to "foreign rice" (S11), and if neither (foreign rice), (S10) ), The setting of rice quality is changed to “new rice” (S12). That is, every time the rice quality selection key 9 is pressed, the setting of the rice quality is changed to “new rice” → “standard” → “old rice” → “old rice” → “foreign rice” → “new rice”. On the other hand, when the input of the rice quality selection key 9 is not performed (S3), the input determination of the start key 11 is performed (S13). When the input of the start key 11 is not performed, the input determination of the rice quality selection key 9 is performed. Returning (S3), the setting of rice quality is repeated. When the start key 11 is input (S13), rice cooking is performed.

In the rice cooking operation, first, a preheating step is performed (S14). In the preheating step, as shown in FIG. 5, the induction coil 3 is ON / OFF controlled so that the detected temperature of the pot temperature detecting means 23 is kept constant at 55 ° C. to promote water absorption of rice.
This preheating step is performed for 15 minutes, and after the elapse of 15 minutes, the preheating step is completed, and the process proceeds to the next high heat step (S15).

In the high heat process, the induction coil 3 is set to 100% O
N (S16), and waits for the boiling of the cooked rice in the pot 2 (S1).
7) This boiling detection is performed when the temperature detected by the lid temperature sensor 6 is 9
This is performed by determining that a point at which the temperature becomes 0 ° C. or higher is boiling. When the boiling is detected, the high heat extension time setting means 19 selects the high heat extension time TE from the high heat extension time storage means 25 based on the setting of the rice quality selection means 18, and the low heat conduction time setting means 27 sets the rice quality selection means 18. Based on the setting, the low heat conduction time storage unit 26 selects and sets the low heat conduction time TY. Table 1 shows the high heat extension time TE and the low heat conduction time TY corresponding to each rice quality.

[0029]

[Table 1]

As shown in Table 1, when the setting of the rice quality selecting means 18 is "new rice" (S18), the high heat extension time TE is set to 300 seconds (S19), and the low heat conduction time TY is set to 50 seconds. (S20), and in the case of "standard" (S21), the high heat extension time TE is set to 240 seconds (S22), and the low heat conduction time TY is set to 40 seconds (S23). In this case (S24), the high heat extension time TE is set to 180 seconds (S25), and the low heat energization time TY is set to 30 seconds (S26), and "Old rice" is set.
In the case of (S27), the high heat extension time TE is set to 120 seconds (S28), and the low heat energization time TY is set to 20 seconds (S29).
In the case of (S27), the high heat extension time TE is set to 60 seconds (S30), and the low heat conduction time TY is set to 10 seconds (S31).

As described above, in the case of fresh rice, which easily absorbs moisture, the evaporation time of water is promoted by increasing the amount of heating by increasing the prolonged time of high heat and increasing the electrical conductivity in low heat heating, and the rice is cooked from boiling. Adjust the time to end shorter. In addition, rice with a property that absorbs less moisture has a shorter high heat extension time and a lower heat conduction rate by lowering the heat on a low heat to reduce the amount of heating to suppress the evaporation of moisture and increase the time from boiling to the end of cooking rice. Adjust to. Therefore, good cooking can be expected regardless of the quality of rice.

Next, the operation of the timer T1 of the control means 20 for measuring the extended flame time TE is started (S32), and it is determined whether or not the count of the timer T1 has reached the extended flame time TE (S33). If the extension time TE is reached,
The process proceeds to the low heat process (S34). Thus, based on the setting of the rice quality selecting means 18, the high heat heating is extended by a time suitable for the rice quality. After the boiling, the free water in the pot 2 becomes a high viscosity necessity because the glue separated from the surface of the rice due to the boiling melts into the water, and foams with the steam generated at the bottom of the pot 2 2 is filled, but the spillover is prevented by the spillover prevention means 5 provided on the lid 4, and it is possible to extend the high-heat heating.

In the low heat process (S34), the timer T2 of the control means 20 for counting the energization time to the induction coil 3 is started (S35), and the count of the timer T2 is compared with the low heat energization time TY (S36). When the timer T2 is less than the low heat conduction time TY, the power supply to the induction coil 3 is turned on.
If the timer T2 has exceeded the low heat conduction time TY (S37), it is compared whether or not the timer T2 is less than 60 seconds (S38). Is turned off (S39),
If the count of the timer T2 is 60 seconds or more, the timer T2
2 is restarted (S35). As a result, the induction coil 3 is turned ON for the set low heat conduction time TY, and
OFF for the time obtained by subtracting the low heat conduction time TY from the second,
The low-heat heating is performed at an energization rate suitable for the rice quality set by the rice quality selection unit 18.

[0034] Rice starch is beta starch in the raw state and does not withstand the taste. However, by converting this starch into an alpha, delicious and digestible cooked rice is cooked up. The pregelatinization conditions require sufficient moisture and heating at 96 ° C. or more for about 20 to 25 minutes. If heating to dry-up with high heat heating after boiling, rice cooking is completed in a short time and sufficient pregelatinization is not performed.However, this problem is solved by performing low heat heating after heating for a predetermined time. .

During the low heat process, the free water in the pot 2 is absorbed by the rice and disappears due to evaporation, and the temperature at the bottom of the pot 2 starts to rise rapidly. When the temperature of the pot temperature sensor 8 becomes 120 ° C. or higher due to the temperature rise (S4
0), the low heat process is ended, and the process proceeds to the steaming process (S4).
1). In the steaming step, as shown in FIG. 5, maintaining the rice at a high temperature for 15 minutes further promotes gelatinization of the rice, and evaporates excess water to cook delicious rice. Cooking is finished with this steaming step (S42).

In this way, the high heat heating is extended even after boiling,
In addition, by adjusting the extension time of the high heat heating based on the setting of the rice quality selecting means 18, the cooked rice in the pan 2 sufficiently reaches the boiling temperature, so that there is no uneven heating, and after the high heat heating is completed, the cooked rice is heated with a low heat. Since the rice is cooked, the pregelatinization of the starch is promoted, and it is possible to cook delicious rice cooked without any uneven cooking and which is sufficiently pregelatinized.

The heating output before the boiling and after the detection of the boiling in the high heat process of the first embodiment is in the continuous ON state (100% in the case of the heating amount), but is not limited to this. For a predetermined time, and for a predetermined time OF
Control based on a so-called duty ratio, such as repeating F, may be used. In this case, the same effect can be obtained.

Embodiment 2 In the rice cooker according to the first embodiment, the ratio of the amount of heating after the detection of boiling to the amount before boiling in the high heat process is set to 100%. However, as shown in FIGS. Is obtained. 10 is a heating pattern of new rice, FIG. 11 is a heating pattern of standard rice, FIG. 12 is a heating pattern of old rice, FIG.
3 shows a heating pattern of old rice, and FIG. 14 shows a heating pattern of foreign rice.

By setting the amount of heating after boiling detection to 90% or more of the amount of heating before boiling, it is possible to suppress a rise in the temperature of the components constituting the heating means, and to avoid the cost of measures for temperature rise, etc. Moreover, it is possible to suppress spills,
In addition, it is possible to cook delicious rice that has no uneven cooking and is fully pregelatinized.

As in the first embodiment, the heating output before the boiling in the high heat process is not limited to the continuous ON state (100% in the case of expressing the heating amount), but is ON for a predetermined time and OFF for a predetermined time. The same effect can be obtained by control based on the so-called duty ratio, such as repeating the operation. For example, the heating output before boiling may be ON for 55 seconds and OFF for 5 seconds. In this case, the heating amount before boiling is about 92%, and the heating amount after boiling detection is 90% or more,
That is, the heating amount may be about 83% or more. At this time, the heating output after the detection of boiling is, for example, 50 seconds ON and 10 seconds OFF.
(The heating amount is about 83%).

Embodiment 3 FIG. 15 is a block diagram showing a rice cooker according to Embodiment 3 of the present invention, which is different from Embodiment 1 described above in that boiling is detected based on the output of pot temperature detecting means 23.

FIGS. 16 and 17 show the relationship between the temperature detected by the pot temperature sensor 8 and the boiling of cooked rice. Since the pot temperature sensor 8 is disposed near the induction coil 3 for heating the bottom of the pot 2, it has a characteristic of detecting a higher temperature than the cooked rice in the pot 2, so that the boiling directly at the temperature detected by the pot temperature sensor 8 Although it is difficult to detect the boiling, it is possible to detect the boiling by determining the amount of cooked rice as shown in FIGS.

That is, FIG. 16 shows the relationship between the detected temperature of the pot temperature sensor 8 and the boiling of the cooked rice when a small amount of rice is cooked. Since the amount of cooked rice is small, the detected temperature of the pot temperature sensor 8 is heated. Rises rapidly, and the pot temperature sensor 8
120 seconds after the temperature reaches 0 ° C., the cooked rice starts boiling. On the other hand, FIG. 17 shows the relationship between the detected temperature of the pot temperature sensor 8 and the boiling of the cooked rice when a large amount of rice is cooked. Since the amount of cooked rice is large, the rise in the detected temperature of the pot temperature sensor 8 is small. It is slower than the case, and the pot temperature sensor 8 is 10
360 seconds after the temperature reaches 0 ° C., the cooked rice starts boiling.

Next, the operation of the third embodiment will be described with reference to the flowchart of FIG. First, the control of the rice cooking operation is started in substantially the same manner as described in the first embodiment,
In the preheating step, the temperature detected by the pan temperature detecting means 23 is 55
The induction coil 3 is ON / OFF controlled so as to be constant at a temperature of ° C. to promote water absorption of rice. This preheating step is performed for 15 minutes, and after the elapse of 15 minutes, the preheating step is finished, and the process shifts to the high heat step (S51).

In the high heat process, first, 100
% Electricity to perform high heat heating (S52), and the pot temperature sensor 8
Is detected to have reached 70 ° C. (S5
3) Start the timer T3 for determining the amount of cooked rice (S)
54). Next, when it is detected that the temperature of the pot temperature sensor 8 has reached 90 ° C. (S55), the timer T3 for determining the amount of cooked rice is stopped (S56). Thereafter, the amount of cooked rice is determined from the count amount of the timer T3 for determining the amount of cooked rice, and a boiling detection time TF is set (S57 to S64). Timer T
When the count of 3 is 60 seconds or less (S57), the amount of cooked rice is reduced (S58), and the boiling detection time TF is set to 120 seconds (S59). If the count of the timer T3 exceeds 60 seconds and is 150 seconds or less (S60), the rice cooking amount is set to a medium amount (S61), and the boiling detection time TF is set to 240 seconds (S62). When the count of the timer T3 exceeds 150 seconds (S60), the amount of cooked rice is increased (S63), and the boiling detection time TF is set to 360 seconds (S64).

Next, the temperature detected by the pan temperature sensor 8 becomes 100
It is determined that the temperature is not less than 100 ° C. (S65). If the temperature is not less than 100 ° C., the timer T4 of the boiling detecting means 17 is started (S66).
When 4 exceeds the boiling detection time TF (S67), it is determined that boiling has occurred, and the boiling detection ends (S68). When the boiling is detected, similarly to the case described in the first embodiment, the extension time of the high heat heating and the energization time of the low heat heating are adjusted based on the setting of the rice quality selecting means 18, and the cooked rice is cooked.

As described above, the boiling is detected by the output of the pot temperature sensor 8, so that the boiling can be detected without providing the lid temperature sensor 6 on the lid 4, the configuration is inexpensive, and the overflow can be suppressed, and the cooking can be further performed. You can cook delicious rice that has been pre-gelatinized without unevenness.

As in the first and second embodiments, the heating output before boiling in the high heat process is
The control is not limited to the continuous ON state (100% when represented by the heating amount), but may be a control based on a so-called energization rate, such as repeating ON for a predetermined time and OFF for a predetermined time. In this case, the same effect can be obtained.

[0049]

As explained above, according to the present invention,
In order to continue heating over high heat even after the cooked rice boiled, and to adjust the heating time based on the quality of rice, new rice, standard rice, old rice, old rice, foreign rice or hard rice or soft rice Regardless of the quality of the rice, it is possible to cook delicious rice with less spillage and even cooking.

Further, by setting the heating amount of the high heat heating after the boiling to 90% or more of the heating amount before the boiling, it is possible to suppress the spillover and to cook a delicious cooked rice without uneven cooking. Can be prevented from rising in temperature.

Further, by detecting boiling based on the temperature detected by the lid temperature detector, it is possible to reliably detect the boiling of the rice to be cooked, to suppress spills, and to cook delicious rice without uneven cooking. Can be.

Further, by judging boiling after a predetermined time from the detection of the predetermined temperature by the pot temperature detector, it is possible to cook delicious rice with less cost, with less spillage, and without uneven cooking. it can

[Brief description of the drawings]

FIG. 1 is a sectional view of a rice cooker according to the present invention.

FIG. 2 is a block diagram of the rice cooker according to the first embodiment.

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

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

FIG. 5 is a diagram showing a heating pattern of fresh rice according to the first embodiment.

FIG. 6 is a diagram showing a heating pattern of standard rice according to the first embodiment.

FIG. 7 is a diagram showing a heating pattern of used rice in the first embodiment.

FIG. 8 is a diagram showing a heating pattern of old rice in the first embodiment.

FIG. 9 is a diagram showing a heating pattern of foreign rice in the first embodiment.

FIG. 10 is a diagram showing a heating pattern of fresh rice according to the second embodiment.

FIG. 11 is a diagram showing a heating pattern of standard rice according to the second embodiment.

FIG. 12 is a diagram showing a heating pattern of used rice in the second embodiment.

FIG. 13 is a view showing a heating pattern of old rice in the second embodiment.

FIG. 14 is a diagram showing a heating pattern of foreign rice according to the second embodiment.

FIG. 15 is a block diagram of a rice cooker according to Embodiment 3.

FIG. 16 is a diagram showing a relationship between a temperature detected by a pot temperature sensor and boiling when cooking a small amount of rice in the third embodiment.

FIG. 17 is a diagram showing a relationship between a temperature detected by a pot temperature sensor and boiling when cooking a large amount of rice in the third embodiment.

FIG. 18 is a flowchart illustrating the operation of the third embodiment.

FIG. 19 is a sectional view of a conventional rice cooker.

FIG. 20 is a front view of an operation panel of a conventional rice cooker.

FIG. 21 is a block diagram of a conventional rice cooker.

FIG. 22 is a flowchart of a conventional rice cooker.

FIG. 23 is a flowchart of a conventional rice cooker.

FIG. 24 is a view showing a heating pattern of fresh rice in a conventional rice cooker.

FIG. 25 is a view showing a heating pattern of standard rice in a conventional rice cooker.

FIG. 26 is a view showing a heating pattern of used rice in a conventional rice cooker.

FIG. 27 is a view showing a heating pattern of old rice in a conventional rice cooker.

FIG. 28 is a view showing a heating pattern of foreign rice in a conventional rice cooker.

[Explanation of symbols]

1 rice cooker body, 2 pots, 3 induction coils, 4 lids,
5 spill prevention means, 6 lid temperature sensor, 7 operation panel, 8 pan temperature sensor, 9 rice quality selection key, 16
Lid temperature detection means, 17 boiling detection means, 18 rice quality selection means, 19 high heat extension time setting means, 22 heating means, 23 pot temperature detection means, 27 low heat conduction time setting means.

 ────────────────────────────────────────────────── ─── Continuing on the front page (72) Inventor Wataru Fujimoto 1728 Koeda, Oaza, Hanazono-cho, Osato-gun, Saitama F-term in Mitsubishi Electric Home Equipment Co., Ltd. 4B055 AA02 BA53 BA63 CA01 CA09 CA22 CA71 CD02 DA02 DB14 GA08 GB07 GB10 GB12 GC12

Claims (4)

[Claims] 1. A pot stored in a rice cooker main body, a heating means for heating the pan, a lid covering an upper opening of the rice cooker main body, a blow-off prevention means provided on the lid,
Boiling detection means for detecting the boiling of the cooked rice in the pan,
A rice quality selecting means for selecting the quality of the rice to be cooked when cooking rice; and a high heat extension time setting means for setting a high heat extension time based on the selection of the rice quality selection means; A rice cooker characterized in that after the boiling detection by the detection means, the high heat heating is performed for the extended heat time set by the high heat extension time setting means, and then the low heat heating is performed. 2. The rice cooker according to claim 1, wherein the heating amount of the high heat after the boiling detection by the boiling detecting means is 90% or more of the heating amount before the boiling. 3. The rice cooker according to claim 1, wherein a lid temperature detector is provided inside the lid, and the boiling detecting means detects boiling based on a temperature detected by the lid temperature detector. vessel. 4. A pot temperature detector for detecting the temperature of the pot, wherein the boiling detecting means determines that the pot is boiling a predetermined time after the pot temperature detector detects a predetermined temperature. Alternatively, the rice cooker according to claim 2.