JP3673438B2 - Insulation control method for cooked rice - Google Patents

Description

[0001]
[Industrial application fields]
The present invention relates to a method for controlling heat retention of cooked rice applied to a heat insulation jar, a rice cooker or the like.
[0002]
[Prior art]
Conventionally, in rice cookers such as rice cookers, when the temperature is lowered, the spoilage bacteria easily grow and the flavor is impaired. On the other hand, when the temperature is raised, the rice is yellowed or browned. For this reason, if the time until meals is short, set the heat retention temperature high so that the flavor is not impaired, and if the time until meals such as sleep is long, The temperature was set slightly lower so that yellowing or the like did not occur and the growth of spoilage bacteria could be suppressed to a minimum.
[0003]
[Problems to be solved by the invention]
However, the conventional heat retention method has the following problems.
[0004]
In other words, it has become possible to accept low temperature insulation regardless of the state of the cooked rice. Specifically, there is a problem that even if it is necessary to keep warm normally during a meal, the operation shifts to low-temperature warming due to an erroneous operation.
[0005]
In addition, the setting of the heat retention temperature is not always appropriate, resulting in the growth of spoilage bacteria or yellowing of cooked rice.
[0006]
In addition, since the energization is controlled only by detecting the temperature of the inner container in the low temperature insulation, the energization amount is constant regardless of the difference in the remaining amount of cooked rice, so the variation in temperature is large and an appropriate insulation state is not necessarily obtained. It was not done.
[0007]
Furthermore, the heat retention temperature is performed only by adjusting the temperature of the inner container, and the lid temperature is mainly used as a so-called dew blowing for preventing condensation of steam generated from cooked rice. For this reason, the lid temperature is set to be high so that the dew can be surely performed in the normal and low-temperature heat retaining state. Accordingly, there has been a problem that the cooked rice turns yellow despite the excessive heating during the low temperature heat retention and the lowering of the inner container temperature.
[0008]
Furthermore, when it is desired to eat during low temperature heat insulation, an appropriate method for canceling low temperature heat insulation has not been provided. For this reason, there existed a problem that the rice which was excellent in flavor could not be eaten.
[0009]
Then, in view of the said problem, this invention aims at providing the heat control method of the rice which can maintain heat | fever appropriately, preventing generation | occurrence | production of yellowing etc., without impairing the flavor of cooked rice.
[0010]
[Means for Solving the Problems]
In order to achieve the above-mentioned object, the present invention achieves the above-mentioned purpose. When the cooked rice is kept warm for a long time, the heat-retaining control of the inner container is performed with the normal heat-retaining temperature and the low-temperature heat-retaining temperature lower than the normal heat-retaining temperature by operating the low-temperature heat-retaining switch In the heat control method of cooked rice,
If returning to the normal heat keeping control from low temperature retaining control, even by operating the low-temperature heat retaining switch is intended to avoid transition to a low temperature heat keeping control.
[0011]
In this case, if the low temperature heat control is less than 4 hours from the start, it is preferable that the normal heat control can be returned to the low temperature heat control again after returning to the normal heat control.
[0013]
In addition, in order to achieve the above object, the present invention achieves the above-mentioned purpose. When the cooked rice is kept warm for a long time, the temperature of the cooked rice is controlled by keeping the temperature of the inner container at the normal warming temperature and the low temperature warming temperature lower than the normal warming temperature. In the control method,
When forcibly returning from the low temperature heat retention control to the normal heat retention control, it is performed in a shorter time than the normal return time from the low temperature heat retention temperature to the normal heat retention temperature.
[0014]
The low temperature heat retention control may be performed within 8 hours and the inner container heat retention temperature is adjusted to 54 to 61 ° C.
[0015]
【Example】
Embodiments of the present invention will be described below with reference to the accompanying drawings.
[0016]
FIG. 1 shows a cross-sectional view of a rice cooker. An outer container 1 contains an inner container 2 supported by an outer container 1a, and these are covered by a lid 3 that is rotatably provided on the shoulder of the outer body 1. It is supposed to be blocked.
[0017]
On the bottom of the outer container 1a, a heating plate 4 that is in pressure contact with the bottom surface of the inner container 2 is disposed. A body heater 6 is wound above the body portion of the inner container 2. Further, a bottom sensor 7 such as a thermistor for detecting the temperature of the inner container in pressure contact with the bottom of the inner container 2 is disposed at the center of the bottom surface of the outer container 1a. It is input to the temperature controller 8 provided.
[0018]
An inner lid 9 is attached to the lid 3, and the inner lid 9 is heated by a lid heater 10 disposed on the peripheral edge of the upper surface, and the inner lid temperature is a lid sensor such as a thermistor. 11 is detected.
[0019]
The temperature control device 8 receives the detected temperatures from the bottom sensor 7 and the lid sensor 11 and adjusts the energization amount to the rice cooking heater 5, the body heater 6 and the lid heater 10, thereby adjusting the rice temperature to a desired temperature. Is controlling. Further, the following low-temperature heat retention control is performed by a sleep switch 12 provided on the exterior body 1.
[0020]
Next, normal heat retention control and low temperature heat retention control after the completion of rice cooking by the rice cooker having the above-described structure will be described with reference to the graph of FIG. 5 and the table of FIG. 6 according to the flowcharts of FIGS.
[0021]
That is, if cooking rice is completed, normal heat insulation is performed in step S1.
[0022]
In this normal heat retention, the energization rate to the rice heater 5 is 0.5 / 30, the energization rate to the body heater 6 is 8/10, and the temperature detected by the bottom sensor 7 (hereinafter referred to as the bottom temperature). The energization / interruption of the heaters 5 and 6 is repeated so that the temperature is 65 to 72 ° C, preferably 67 to 69 ° C.
[0023]
On the other hand, while the energization rate to the lid heater 10 is 1, the temperature detected by the lid sensor (hereinafter referred to as lid temperature) is always 6 ° C. higher than the bottom temperature, that is, 71 to 78. The energization / interruption of the lid heater 10 is repeated so that the temperature of the lid heater 10 is set to ° C, preferably 73 to 75 ° C. As a result, water vapor generated from the cooked rice is not attached to the inner lid 9, and so-called dew blowing is performed.
[0024]
In step S2, it is determined whether the good night switch 12 is turned on. If the good night switch 12 remains in the off state, the normal heat insulation in step S1 is continued, and if it is in the on state, the process proceeds to step S3 in FIG. 2 to start the low temperature heat insulation control.
[0025]
However, even if the sleep switch 12 is operated under a predetermined condition, the low temperature heat control is not shifted. Specifically, (1) when normal heat insulation control is not performed at all (for example, before cooking or during rice cooking), or (2) once returned from low temperature heat insulation control to normal heat insulation control (in this case, If the low temperature heat control is less than 4 hours, it can be accepted.) (3) When cooking something other than white rice (for example, brown rice), (4) When the low temperature heat control is terminated without being canceled halfway, etc. Do not accept low temperature insulation control.
[0026]
The low temperature heat retention control is performed according to the flowchart of FIG.
[0027]
First, in step S11, the heat insulation control is performed in the first heat insulation mode in step S12 until the low temperature heat insulation time H reaches the first set time a (in this embodiment, the time until the bottom temperature reaches 57 ° C.). In the first heat retention mode, the energization to the rice heater 5 and the body heater 6 is stopped, and the energization rate to the lid heater 10 is set to 1 so that the lid temperature becomes 64 ° C. which is 7 ° C. higher than the bottom temperature. Repeat blocking.
[0028]
As described above, the reason why the lid temperature is set higher than that in the normal temperature control immediately after the start of the low temperature temperature control is that the inner container 2 is not heated, and as a result, the difference between the cooked rice temperature and the bottom temperature becomes large. This is because it tends to decrease and condense on the inner lid 9.
[0029]
Next, if the bottom temperature decreases to 57 ° C., the second heat retention time H in step S13 until the low temperature heat retention time H reaches the second set time b (8− (a + 2), 4 hours in this embodiment). Keep warm control in warm mode. In the second heat retention mode, the energization rate to the rice cooker heater 5 is set to 0.5 / 30, the energization rate to the body heater 6 is set to 8/10, and the bottom temperature is maintained at 57 ° C. as in the normal heat retention. (In this embodiment, the energization time is about 70% of the normal heat retention).
[0030]
The reason why the bottom temperature is 57 ° C. is that the cooked rice does not turn yellow even if it is maintained at this temperature for a long time, and is the optimum temperature for minimizing the occurrence of spoilage bacteria. Further, the lid temperature is set to be 4 ° C. higher than the bottom temperature, and the inner lid 9 is exposed in the same manner as in the first heat retention mode. In this case, the generated water vapor is kept at a lower temperature than the normal heat retention. Considering that the amount is small, the lid temperature is set slightly lower.
[0031]
Subsequently, if the second set time b has elapsed, it is determined whether or not 8 hours have elapsed in step S15. Here, the reason for determining the time to be 8 hours is that it is optimal for maintaining the state of eating cooked rice while suppressing the occurrence of spoilage bacteria.
[0032]
And until low temperature heat retention time passes for 8 hours, heat retention control is performed in 3rd heat retention mode in step S16. In this 3rd heat retention mode, electricity supply to the rice cooking heater 5 and the body heater 6 is controlled similarly to the said normal heat retention control.
[0033]
On the other hand, the energization rate to the lid heater 10 is set to 1, and the energization / interruption is repeated so that the lid temperature is 4 ° C. higher than the bottom temperature. That is, the inner lid 9 is dewed so that a temperature higher by 4 ° C. can be maintained with respect to the bottom temperature that gradually rises as the rice cooker heater 5 and the body heater 6 are energized.
[0034]
In addition, the said low temperature heat retention time can be freely set by the operation part which is not shown in figure, and the value is a maximum of 12 hours.
[0035]
In addition, in the low temperature heat retention control, the energization rate is set and the energization / interruption of the heaters 5, 6, and 10 is repeated so that a desired temperature can be obtained. This is to suppress the variation in temperature change to a smaller extent.
[0036]
If the user wants to eat during the low temperature heat control, the sleep switch 12 can be turned off to return to the normal heat state. That is, in step S4, it is determined whether or not the good night switch 12 is turned off during the low temperature heat retention. If it is in the on state, the low temperature heat insulation control is continued, and if it is in the off state, the return mode is entered in step S5. To do.
[0037]
In the return mode of step S5, the heat retaining state is returned to the normal heat retaining according to the flowchart of FIG.
[0038]
First, in step S21, the energization rate to the rice cooker heater 5 is set to 1, and the inner container temperature is rapidly raised (first return mode). This first return mode is continued until one minute has elapsed since the shift to the return mode in Step S22, or until the bottom temperature exceeds 80 ° C.
[0039]
And if any one of the conditions of step S22 is satisfied, it will transfer to step S23 and while setting the energization rate to the rice cooking heater 5 to 0.5 / 30, the energization rate to the trunk heater 6 to 8/10, The energization / interruption is repeated so that the bottom temperature is 65 to 72 ° C, preferably 67 to 69 ° C.
[0040]
On the other hand, the energization rate to the lid heater 10 is set to 1, and the energization / interruption is repeated so that the lid temperature is 5 ° C. higher than the bottom temperature (second return mode). This second return mode is performed until 1 hour 30 minutes have elapsed since the shift to the return mode in step S24.
[0041]
As described above, even during the low temperature heat control, by turning off the good night switch 12, the heat retention state of the rice is rapidly returned to the normal heat retention state, and the temperature of the cooked rice is returned to a temperature suitable for eating. be able to.
[0042]
In addition, although the said Example demonstrated the case where it applied to a rice cooker, of course, you may apply to the electronic jar only for heat retention.
[0043]
Moreover, in the said Example, although feedback control which controls heat retention was performed by controlling the electricity supply rate to the rice cooking heater 5 and the body heater 6 based on the temperature detected by the bottom sensor 7, it transfers to low temperature heat control. It is also possible to estimate the cooked rice capacity from the state of change in the bottom temperature at the time of heating, and to control the energization based on the estimated cooked rice capacity. Please input data correspondingly.)
[0044]
That is, feedforward control may be performed by adjusting the energization rates to the rice cooking heater 5 and the body heater 6 in advance according to the estimated cooked rice capacity. According to this, a more appropriate warming temperature can be obtained, and the conventional temperature variation can be minimized.
[0045]
Further, in the above-described embodiment, it is preferable to provide a display portion that shows the on / off state of the sleep switch 12. This display part can be constituted by a display lamp such as an LED provided in the front part of the exterior body 1 or a liquid crystal panel. In particular, when displaying by the liquid crystal panel, it is preferable to display the remaining time of the low temperature heat insulation. . Further, the display is performed when the good night switch 12 is turned off during the low temperature heat control and the operation is forcibly returned to the normal heat control, or when the acceptance is rejected without satisfying the above-described conditions. May be.
[0046]
【The invention's effect】
As is apparent from the above description, according to the present invention, when returning from the low temperature heat control to the normal heat control, the operation is not shifted to the low temperature heat control depending on the manual operation, so there is no risk of malfunction.
[0047]
Further, since the temperature change of the inner container after that is estimated from the difference in the amount of cooked rice at the initial stage of the low temperature heat control, the energization control is performed, so that more appropriate temperature control is possible.
[0048]
In addition, even during the low temperature heat control, it was forced to return to the normal heat control, so that the rice can be made an optimal flavor, and the practicality can be increased by letting it run in a short time. Is possible.
[0049]
In particular, since the inner container temperature at the time of the low temperature heat control is set to an optimal value, the inner container can be kept warm so that no spoilage bacteria are generated in the cooked rice and yellowing or the like does not occur. .
[Brief description of the drawings]
FIG. 1 is a front sectional view of an electric rice cooker according to the present embodiment.
FIG. 2 is a flowchart showing heat retention control in the temperature control apparatus of FIG. 1;
FIG. 3 is a flowchart showing the low temperature heat retention of FIG. 2;
FIG. 4 is a flowchart showing a return mode of FIG.
FIG. 5 is a graph showing the relationship between time and bottom temperature during low temperature heat retention control.
FIG. 6 is a table showing the relationship between the energization rate to each heater and the control temperature in each heat retention state.
[Explanation of symbols]
2 Inner container 3 Lid 5 Rice cooker 6 Body heater 7 Bottom sensor 8 Temperature controller 9 Inner lid 10 Lid heater 12 Good night switch

Claims (4)

In the case where the cooked rice is kept warm for a long time, in the temperature control method of the cooked rice, the temperature of the inner container is controlled at the normal temperature and the low temperature temperature lower than the normal temperature by operating the low temperature temperature switch.
If returning to the normal heat keeping control from low temperature retaining control, thermal insulation method of controlling rice, characterized in that to avoid transition to a low temperature heat keeping control even by operating the low-temperature thermal insulation switch.   2. The method for controlling the heat retention of cooked rice according to claim 1, wherein if the low temperature heat control is less than 4 hours from the start, the control can be transferred to the low temperature heat control again after returning to the normal heat control.   In the case of keeping the cooked rice for a long time, in the cooked rice warming control method for controlling the warming temperature of the inner container with the normal warming temperature and the low temperature warming temperature lower than the normal warming temperature,
  A method for controlling heat retention of cooked rice, characterized in that when the low temperature heat retention control is forcibly returned to the normal heat retention control, it is performed in a shorter time than the normal return time from the low temperature heat retention temperature to the normal heat retention temperature.   4. The method for controlling the heat retention of cooked rice according to claim 1, wherein the low temperature heat retention control is performed within 8 hours and the inner container heat retention temperature is adjusted to 54 to 61 ° C. 5. .

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