JP2006087483A - Rice cooker - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To satisfactorily finish rice cooking by improving timing of soaking rice with not-heated water in the case of reserved rice cooking. <P>SOLUTION: The rice cooker is provided with: a water reservation part for reserving water required for rice-cooking; and a transporting means for transporting the water reserved in the water reservation part to a pot. The transporting means is made to operate at a time of starting soaking without heating before rice cooking calculated from the time of starting or completing reserved rice cooking (S4 to S6). Thus, timing of soaking of the rice with not-heated water is improved to satisfactorily finish rice cooking. <P>COPYRIGHT: (C)2006,JPO&NCIPI

Description

  The present invention relates to a rice cooker having a reservation function.

  Conventionally, what has a reservation function is provided in the rice cooker. This can be reserved for the start or completion time of rice cooking, and the user puts the washed or unwashed rice into the kettle and then puts water to reserve the start or completion time of rice cooking. By doing, rice cooking is automatically started or completed at that time.

However, in this case, the water is usually kept in the kettle from the time of making a reservation, and it takes a long time to immerse the rice in the water. For this reason, the water absorption degree of rice becomes excessive, and water required for boiling continued in the rice cooking process is insufficient, so that the cooked rice is hardened.
However, if you try to put water in the kettle during the scheduled time, the work is cumbersome, and the time to put it in is too late, so the time to soak the rice in water may be shortened, Cooking rice is started and gelatinization is performed before the rice has sufficiently absorbed water, and the core remains in the cooked rice.
As described above, it is difficult to optimize the timing of adding water when making reserved rice.

In contrast, the rice cooker is provided with a water storage tank, and also includes a water supply channel and a water supply valve for transferring the water stored in the water storage tank to the kettle, and controls them by a control device such as a microcomputer. There is also a type in which water is poured into a kettle at a time calculated by subtracting the time required for cooking from the time of completion of cooking.
Japanese Patent Laid-Open No. 9-98884

  According to the above, the timing of adding water when making reserved rice is fixed. However, the timing of adding water to the kettle is at the start of the first heating and soaking process of the rice cooking operation. The heating and soaking process involves heating the water with a heater and heating means while immersing the rice in water. During the process, the rice is heated little by little, so the rice is not soaked only with unheated water, and the cooking proceeds little by little. It will be cooked without much difference from when it was soaked in water for a short time.

  The present invention has been made in view of the above circumstances, and therefore, the purpose of the rice cooker is to make rice cooked in a well-prepared condition, so that the rice can be soaked with water without heating at the time of reservation rice cooking. In offer.

  In order to achieve the above object, the rice cooker of the present invention comprises a kettle, a heating means for heating the kettle, and a control means for controlling the heating means, and the start or completion time of rice cooking can be reserved. In this case, a water storage part for storing water necessary for rice cooking and a transfer means for transferring the water stored in the water storage part to the kettle are provided, and the transfer means is used to start or complete reserved rice cooking. It was made to operate | move at the time which starts the immersion by the non-heating before cooking rice computed from time.

  According to the said means, the water stored in the water storage part is put into the kettle at the time which starts the immersion by the non-heating before cooking calculated from the time of the start or completion of the reserved rice cooking. Thus, the rice can be soaked in a timely manner with unheated water when making reserved rice, and the rice can be cooked in good condition.

Hereinafter, a first embodiment (first embodiment) of the present invention will be described with reference to FIGS.
First, in FIG. 2, the whole structure of the rice cooker is shown, and the inner container 2 is installed in the main body container 1. More specifically, a cradle 3 is fixed to the inner and lower portions of the main body container 1, and the inner container 2 is placed on the cradle 3, and the upper edge portion of the inner container 2 is fixed to the main body container 1. Yes.

Inside the inner container 2, the hook 4 is detachably accommodated, and a temperature sensor 5 as temperature detecting means for detecting the temperature of the hook 4 is disposed at the center of the bottom of the inner container 2. . Further, in this case, a heating coil 6 is disposed on the cradle 3 as a heating means for heating the hook 4. The heating coil 6 is configured to generate heat by heating the pot 4 by induction heating when a high frequency current is supplied from an inverter device 7 disposed below the cradle 3.
In addition, a fan 8 for cooling the inverter device 7 is disposed below the cradle 3, and a cord reel 9 is disposed below the main body container 1.

  On the other hand, a lid 10 is pivotally supported by a support shaft 11 on the main body container 1 so as to be opened and closed, and an inner lid 12 is provided on the hook 4. And in the front part (left side in FIG. 2) between the main body container 1 and the inner container 2, the water storage tank 13 is arrange | positioned as a water storage part, and the front upper part of the main body container 1 etc. are suitably set in this water storage tank 13. The user can supply water from the location (not shown). The water storage tank 13 may be detachable so that the user can supply water outside the main body container 1.

  A pump 14 is disposed inside the water storage tank 13. In this case, in this pump 14, an impeller (not shown) in the pump 14 is responsive to the rotation of a movable magnet 15 provided outside the water storage tank 13 by a motor (not shown in FIG. 2). Thus, by rotating, the water W in the water storage tank 13 is pumped out, and a first water guide pipe 16 for guiding the pumped water is disposed from the water storage tank 13 to the peripheral side of the hook 4. .

  The tip of the first water conduit 16 is located at a portion of the support shaft 11, and this portion is connected to a second water conduit 17 disposed inside the lid 10 in a watertight and bendable manner. Yes. Therefore, the second water guide pipe 17 is bent at the portion of the support shaft 11 as the lid 10 is opened and closed with respect to the first water guide pipe 16, and even if it is bent, the portion is watertight. The second water conduit 17 guides the water guided to the first water conduit 16 further forward.

  The distal end portion of the second water conduit 17 is directed downward at the central portion in the lid 10, and the water receiving casing 18 fixed on the inner plate 10 a of the lid 10 has a tip (downward). A funnel port 19 is located. Further, below the funnel port 19, a water injection tube 20 penetrating the center portion of the inner plate 10 a is located. The inner lid 12 is fitted to the water injection tube 20, and the water injection tube 20 is attached to the water injection tube 20. It faces the kettle 4.

With the above configuration, the water W stored in the water storage tank 13 is pumped out by the pump 14, passed from the first water conduit 16 through the second water conduit 17, through the funnel port 19, and from the water injection tube 20 to the inside of the pot 4. Thus, the transfer device 21 is configured as a transfer means for transferring the water stored in the water storage tank 13 into the pot 4.
The inner lid 12 fitted to the water injection tube 20 opens and closes the opening on the upper surface of the hook 4 as the lid 10 is opened and closed.

  Therefore, a control device 22 is disposed on the back side of the front surface portion of the main body container 1. Although not shown in detail, the control device 22 has a storage device and a time discriminating device in addition to the arithmetic device, and functions as a control means for controlling the overall operation of the rice cooker.

The control device 22 is also shown in FIG. As apparent from FIG. 3, various operation signals are input to the control device 22 from the operation input unit 23. The operation input unit 23 is composed of various operation switches (not shown) provided in the operation panel 24 provided on the front side of the front surface portion of the main body container 1, and reservation setting for rice cooking is possible in the operation switches. There is a simple reservation switch, a time setting switch that can set the start time or completion time of rice cooking in the reservation setting, a hardness setting switch that can set the hardness after cooking rice, and a start switch.
In addition, a temperature detection signal is input from the temperature sensor 5 to the control device 22.

  And based on those inputs and the control program memorize | stored previously, the control apparatus 22 controls the display part 25 which exists in the said operation panel 24, and also controls the said heating coil 6 via the inverter apparatus 7 as mentioned above. In addition, the motor 26 for driving the magnet 15 of the transfer device 21 and the fan 8 for cooling the inverter device 7 are controlled via a drive circuit 27.

Next, the operation of the above configuration will be described.
When the reserved rice is cooked, the user puts the washed or unwashed rice into the kettle 4, closes the inner lid 12 and the lid 10, and puts the required amount of water into the water storage tank 13. In this state, operate the reservation switch on the operation panel 24, set the cooking start time or completion time with the time setting switch, set the desired cooked hardness with the hardness setting switch, and start. Operate the switch.

When the start switch is operated, the control device 22 starts (starts) the operation shown in FIG. 1, and first determines whether or not reserved rice cooking is set (step S1). If it is determined in this step S1 that reserved rice cooking is not set (NO), the process proceeds to another, for example, normal cooking process, but if it is determined that reserved rice cooking is set (YES), setting is made. The hardness after cooking is certified (step S2), and the average value of the past day of the temperature detected by the temperature sensor 5 is called from the storage device (step S3).
In the case of the present embodiment, the temperature sensor 5 also serves to detect the temperature of rice cooking in the pot 4, and the average temperature of the past day is excluding the rice cooking temperature, that is, rice cooking is performed. The control device 22 calculates the detected temperature at the time when there is not, and stores it in the storage device.

  Thereafter, the time for supplying water into the hook 4 is calculated (step S4). The water supply time is a time to start soaking by non-heating before cooking, which is calculated from the start or completion time of the reserved rice cooking. For the calculation, the past of the temperature detected by the temperature sensor 5 is used. In addition to taking into account the average value of the day, it is also adapted to the hardness (setting hardness) after cooking as instructed by the user.

  FIG. 4 shows the relationship between the average value of the detected temperature to be taken into consideration in the past and the execution time of the non-heating immersion, and the larger the average value of the detected temperature in the past day, the greater the immersion in non-heating. In other words, the execution time of the immersion without heating is determined with a negative correlation based on the average value of the detected temperature for the past day. In addition, the hardness after cooking is instructed by the user, so that the greater the instructed hardness, the longer the soaking time by non-heating is to be met. In the range of 0.5 to 3 hours.

  Due to this determination, the water supply time in step S4 is calculated by subtracting the non-heating soaking determination execution time from the reserved rice cooking start time or subtracting the rice cooking time from the reserved rice cooking completion time. After that, the determination execution time of the non-heating soaking is subtracted from it. Thus, the time to start soaking by non-heating before cooking rice is calculated.

Thereafter, the control device 22 determines whether or not the current time has reached the time to start the soaking by non-heating before cooking, calculated in step S4 (step S5), and has reached (YES). If it is judged that the pump 14 is operated by the movable magnet 15 of the transfer device 21, the water stored in the water storage tank 13 is supplied from the first water conduit 16 to the second water conduit 17, the funnel port 19, The water bottle 20 is sequentially transferred into the pot 4 and supplied (step S6).
Thereafter, the heating coil 6 is operated by the inverter device 7 to generate heat and heat the hook 4 (step S7).

  Then, from the temperature detection result by the temperature sensor 5, it is determined whether or not the water in the pot 4 has boiled (step S8). If it is determined that the water has boiled (YES), the pot by the heating coil 6 is used. 4, the degree of heat generation (heating) is lowered (step S 9), and further, it is determined from the temperature detection result by the temperature sensor 5 whether or not the inside of the pot 4 has reached the rice cooking completion temperature (step S 10). If it is determined (YES), heat generation (heating) of the pot 4 by the heating coil 6 is stopped (step S11), and rice cooking is finished (completed).

  In this way, in this configuration, the water stored in the water storage tank 13 is put in the kettle 4 at the time when the soaking by non-heating before cooking is started, calculated from the start or completion time of the reserved rice cooking. It is done. Thus, the rice can be soaked with unheated water in a timely manner when making the reserved rice, and the cooked rice can be cooked well.

FIG. 5 shows the change over time in the hardness of cooked rice after cooking, according to the inventor's experiment, when the rice was soaked in non-heated water for 3 hours, and when the soaking was not performed at all. Represents. In the figure, the characteristic line A is the result when the rice is soaked with non-heated water for 3 hours, and the characteristic line B is the result when the soaking is not performed at all. The former is more time-consuming than the latter. But it turns out that cooked rice is hard to harden.
FIG. 6 also shows the relationship between the rice soaking time with unheated water and the amount of reducing sugar contained in the cooked rice after cooking, which is also shown by the inventor's experimental results. It can be seen that the longer the soaking time of rice, the greater the amount of reducing sugar contained in the cooked rice after cooking.
This is because the rice absorbs the unheated water before cooking rice, and the gelatinization of the rice starch during the subsequent rice cooking is sufficiently advanced, and it is certain that the rice is soaked with unheated water It shows good things.

  On the other hand, FIG. 7 shows the time-dependent change in the number of viable bacteria in the soaking water according to the inventor's experiment according to the soaking temperature, and 100 [g] unwashed rice was soaked in 100 [g] water and the water after 8 hours. The number of surviving bacteria was 6.3 times at a soaking temperature of 5 [° C], 14 times at 20 [° C], and 263 times at 37 [° C]. When the soaking temperature was 37 [° C.], the number of surviving bacteria in water increased 12 times after 4 hours and 36 times after 4 hours, and 263 times after 6 hours. The value of the viable cell count after 6 hours in water at 37 ° C. is 10000 [CFU / ml], which is 100 times the standard value of tap water. Thus, the higher the temperature, the greater the number of viable bacteria in the immersion water over time.

  8 and 9 show the change over time in hydrogen ion activity (pH) when 100 [g] unwashed rice and ordinary rice are both immersed in 100 [g] water. The initial pH is 6.73 to 7.00 for each rice type and temperature, and the pH of water soaked for 6 hours at 5 [° C.] 6.85, the water soaked with washed plain rice was 6.83, and the pH of water soaked at 20 [° C.] for 6 hours was 6.72 with water soaked with unwashed rice, soaked washed plain rice The pH of water soaked at 37 [° C.] for 6 hours was 6.54 for water soaked with non-washed rice, and 6.69 for water soaked with washed plain rice. 51. At this time, it was already sour.

The pH of water soaked at 37 [° C.] for 18 hours was 4.02 in water soaked with non-washed rice and 4.75 in water soaked with washed normal rice. At this time, an unpleasant odor was also felt along with acidity. The hydrogen ion concentration calculated from the pH at this time was 1.5 × 10 ⁻⁷ [mol / ml] in the initial stage and 8.9 × 10 ⁻⁵ [mol / ml] after 18 hours.
The pH of water soaked at 20 [° C.] for 18 hours was 5.81 for water soaked with non-washed rice and 6.05 for water soaked with washed normal rice (the others were both sour). See).

  In view of these, in the present configuration, the non-heated soaking time is set to 0.5 to 3 hours, which can suppress the growth of bacteria and increase in pH, and is a sanitary and good-tasting cooked rice Can be provided.

  In the case of this configuration, the temperature sensor 5 is provided as a temperature detecting means for detecting the temperature of the pot 4, and the non-heating soaking time is determined with a negative correlation based on the average value of the detected temperature for one day. Like to do. As a result, for example, as the temperature rises depending on the season, the soaking time by non-heating is shortened, so as in the above case, the growth of bacteria and the increase in pH can be suppressed, and sanitary and good-tasting cooked rice is provided. Can do.

FIG. 10 shows the hardness of cooked rice after immersing 500 [g] unwashed rice with 700 [g] water at 30 [° C.] and compressing the cooked rice with a plunger. By experiment, it represents by soaking time. The maximum compression load of cooked rice by the plunger is 1.45 [N] at the initial value (no soaking), 1.61 [N] when soaking for 2 hours, and 1 when soaking for 4 hours. , 79 [N], and when immersed for 6 hours, it became 1,89 [N], and a tendency to gradually become hard was observed.
On the other hand, in this configuration, the duration of the non-heating soaking is set to 0.5 to 3 hours as described above, which may cause the hardness of the cooked rice to be too high. Absent.

  Furthermore, in the present configuration, the duration of non-heating soaking is determined by the hardness after cooking, which is instructed by the user, specifically, the cooking instructed by the user. The higher the instructed hardness is, the greater the instructed hardness, and the longer the soaking time by non-heating, the more the desired hardness can be obtained in the cooked rice. .

  11 and 12 show the second and second examples (second and second embodiments) of the present invention, and the same parts as those in the first example are denoted by the same reference numerals. A description will be omitted, and only different parts will be described.

[Second Embodiment]
In the second embodiment shown in FIG. 11, the transfer device 21 is provided with a sterilization device 31 as sterilization means. Specifically, the sterilization apparatus 31 is provided, for example, in the middle part of the first water conduit 16 or the second water conduit 17, and includes a discharge electrode 32 located in the center of the tube, and the discharge electrode 32. The structure includes an enclosed insulator 33, a photocatalyst 34 using, for example, titanium oxide filled in the periphery of the insulator 33, a counter electrode 35 embedded in a tube wall made of an insulating material, and a voltage application device 36.

  With this configuration, the voltage application device 36 applies a voltage between the discharge electrode 32 and the counter electrode 35, whereby ultraviolet rays are emitted from the discharge electrode 32. The emitted ultraviolet light excites electrons in the titanium oxide molecules of the photocatalyst 34 to generate holes and free electrons. And a hole oxidizes the oxygen in the water which passes along the inside of a pipe | tube, and ozone is destroyed, and ozone destroys the cell membrane of microorganisms and kills a microbe. Thus, since the water transferred from the water storage tank 13 into the kettle 4 can be sterilized, cooked rice with a more sanitary and better taste can be provided.

[Third embodiment]
In the third embodiment shown in FIG. 12, the water storage tank 13 is provided with a sterilization apparatus 41 as a sterilization means. Specifically, the sterilization apparatus 41 is attached to the outer surface of the bottom of the water-transmitting water storage tank 13, and a light-emitting body (for example, LED) 42 that emits light in the ultraviolet region has a light-transmitting property. It is embedded in a covering member 43 having

  With this configuration, the illuminant 42 emits light toward the water in the water storage tank 13, thereby destroying the DNA of microorganisms in the water and killing the bacteria. Thus, also in this case, since the water transferred from the water storage tank 13 into the kettle 4 can be sterilized, it is possible to provide more sanitary and good-tasting cooked rice.

  Note that the temperature detecting means exemplified by the temperature sensor 5 is not the temperature of the hook 4 but the ambient temperature of the hook 4, for example, the air temperature between the inner container 2 and the main body container 1, the air temperature in the lid 10, May be configured to detect the outside air temperature of the entire rice cooker. Moreover, this temperature detection means may be what does not serve as detecting rice cooking temperature.

In addition, the water storage tank 13 may exist in the side part or the rear part between the main body container 1 and the inner container 2, or may exist in the lid 10. In particular, when the water storage tank 13 exists above the hook 4 such as the inside of the lid 10, water can be supplied into the pot by gravity, so that the transfer means consists of a simple water supply path and a water supply valve that opens and closes it. Also good.
Further, the heating means for heating the hook 4 may be an electric heater instead of the heating coil 6.
In addition, the present invention is not limited to the embodiments described above and shown in the drawings, and can be implemented with appropriate modifications within a range not departing from the gist.

The flowchart at the time of the reservation rice cooking which shows 1st Example of this invention Vertical side view of the entire rice cooker Electrical configuration block diagram Characteristic diagram 1 Characteristic diagram 2 Characteristics chart 3 Characteristic diagram 4 Characteristic diagram 5 Chart showing characteristic diagram 5 Figure 6 (Chart shown in the table) Partially enlarged longitudinal sectional view showing a second embodiment of the present invention FIG. 2 equivalent view showing a third embodiment of the present invention.

Explanation of symbols

  In the drawings, 4 is a hook, 5 is a temperature sensor (temperature detection means), 6 is a heating coil (heating means), 13 is a water storage tank (water storage section), 21 is a transfer device, 22 is a control device, and 31 and 41 are excluded. A bacteria apparatus (sanitization means) is shown.

Claims (5)

In a thing which has a kettle, a heating means for heating the kettle, and a control means for controlling the heating means, the start or completion time of rice cooking can be reserved,
A water storage section for storing water necessary for cooking,
A transfer means for transferring the water stored in the water reservoir to the kettle;
A rice cooker characterized in that the transfer means is operated at the time of starting soaking by non-heating before cooking, which is calculated from the start or completion time of reserved rice cooking.   The rice cooker according to claim 1, wherein the dipping time by non-heating is 0.5 to 3 hours.   The temperature detecting means for detecting the temperature of the kettle or its surroundings is provided, and the execution time of the non-heating soaking is determined with a negative correlation based on the average value of the detected temperatures per day. rice cooker.   The rice cooker according to claim 1, wherein the dipping time by non-heating is determined by the hardness after cooking as instructed by the user. The rice cooker according to claim 1, wherein the transfer means or the water storage part has a sterilization means for removing bacteria in the water.

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