JP2003144311A - Rice cooker - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide more delicious cooked rice by heating the inside of a pot and uniformly elevating a temperature only by heating from the circumference of the bottom of the pot. SOLUTION: By discharging steam from an opening on the pot, the inside of the pot can be uniformly heated while preventing drying, nonuniformity in cooking is reduced, and the taste of cooked rice can be more improved in the entire inside of the pot.

Description

Detailed Description of the Invention

[0001]

FIELD OF THE INVENTION The present invention relates to a rice cooker.

[0002]

2. Description of the Related Art FIG. 9 shows the structure of a conventional general rice cooker. A pan 25 is detachably mounted inside the main body 24, and an openable lid 26 is provided to cover the top surface of the pan. Further, pot heating means 27 is placed at the bottom of the pot 25 to heat the rice and water in the pot 25, and a lid heating means 28 is placed in the lid 26. Further, in order to control the heating state of the cooked rice, a pan temperature detecting means 29 for detecting the temperature of the pan 25 and a lid temperature detecting means 30 for detecting the temperature of the upper surface of the pan 25 are arranged at the bottom of the pan 25. The control means 31 operates the pot heating means 27 and the lid heating means 28 at appropriate times based on the temperatures detected by the pot temperature detecting means 29 and the lid temperature detecting means 30.

The operation of the above configuration will be described. Put the amount of rice to cook rice in the pan 25 and water suitable for the amount of rice. The rice cooking process of a typical rice cooker is classified into the submersion, cooking, and steaming processes, and rice becomes rice through the above processes. When the user starts cooking rice, the control means 31 uses the temperatures detected by the pan temperature detecting means 29 and the lid temperature detecting means 30 to make the rice and water in the pan 25 necessary for the above-mentioned inundation, cooking and steaming steps. The temperature and time are maintained.

FIG. 10 shows changes in the gelatinization degree, which shows the rate of change of rice into rice during the rice cooking process. From FIG. 10, it can be seen that in the cooking process for heating and boiling rice, the gelatinization degree rapidly increases as the heating amount is increased. However, when the water in the pan 25 is exhausted and the cooking process is completed, the amount of heating of the pan heating means 27 must be particularly reduced in order to avoid burning the cooked rice.

There is steam cooked rice in which rice is placed in an atmosphere filled with steam and cooked under the condition that each grain of rice is evenly heated while receiving moisture and heat.

A rice cooker using steam is disclosed in Japanese Patent Application Laid-Open No. 02-28
3328 gazette. The steam rice cooker shown in FIG. 11 will be described. The main body 32 locks the rice-cooking tray 33 in the vicinity of the central portion of the inside thereof, and the bottom thereof is provided with a partition plate 34 having many holes through which rice grains cannot pass. A water supply shower 35 is provided on the upper portion, and water is uniformly sprayed on the set rice grains. A steam supply unit 36 is provided in the lower portion, and the water supplied from the water supply pump 37 is vaporized to inject the steam from below.

With the above-mentioned structure, rice is cooked while spraying steam from below and spraying water from above at appropriate times.

[0008] As described above, it is general that a very large-scale device is provided for supplying water and heat to rice grains.

[0009]

[Patent Document 1] Japanese Unexamined Patent Publication No. 02-283328

[0010]

In a general domestic rice cooker, a pot heating means arranged at the bottom of the pot is mainly for heating rice and water in the pot, and the heating means in the lid is in the pot. Proper heating is difficult because the rice passes through the space above the water. If the heating amount is insufficient or the heating amount is too large, only the upper surface is dried and it is difficult to uniformly heat the rice and water in the pan.

Further, in the steaming step, the heating amount of the pan heating means must be particularly reduced in order to prevent charring of the cooked rice.

In addition to the steam that heats the rice grains, the steam rice cooker that solves the above problems requires a water supplier that compensates for the water shortage in the steam rice for the rice grains. Therefore, the steam rice cooker has a very complicated structure and is difficult to be applied as a domestic rice cooker.

[0013]

In order to achieve the above object, the present invention has a constitution in which, in addition to heating by a pot heating means, steam from above the pot is sprayed to heat cooked rice and water from above the pot. Is.

[0014]

BEST MODE FOR CARRYING OUT THE INVENTION The invention according to claim 1 of the present invention comprises a pot, a pot heating means for heating the pot, a lid for covering the opening of the pot, and a steam generating means, The steam generating means has a water tank and an electromagnetic induction heating type water tank heating means, and further has a steam injection hole for injecting steam into the pot from the opening of the pot. By setting the necessary water in the pan from the beginning, it is not necessary to separately provide a means for supplying water, and the heating of rice and water when cooking rice is supplemented from above. Furthermore, when steamed, the rice can be heated without burning, and cooked rice with a better taste can be obtained.

The invention according to claim 2 of the present invention is
By making the water tank detachable, it is possible to easily wash and keep the water tank clean after cooking rice.

The invention according to claim 3 of the present invention is
A steam heating means for heating the steam generated from the steam generating means according to claim 1 is provided, and a structure for injecting or generating superheated steam exceeding 100 ° C. is provided in the pot, thereby efficiently supplying energy. It can be implemented well.

[0017]

(Embodiment 1) A first embodiment of the present invention will be described with reference to FIG. Reference numeral 1 shown in FIG. 1 denotes a main body of a rice cooker in which a detachable pot 2 is installed. Further, a lid 3 that covers the upper surface of the pot 2 is installed so as to be openable and closable.

Further, the pot heating means 4 for heating the pot 2 and the pot 2
The pot temperature detecting means 5 for detecting the temperature of the is placed inside the main body 1. A water tank 6 is provided inside the main body 1. The water tank 6 has a water tank heating means 7, and the water tank 6 and the water tank heating means 7 constitute a steam generating means 38.

Further, a part of the upper surface of the pot 2 is connected to the steam generating means 38 by the steam pipe 8, and the opening on the upper surface of the pot 2 serves as a steam hole 9. An on-off valve 10 is installed in the steam cylinder from which steam is released from the pan 2 to the outside of the main body 1.
Further, inside the main body 1, based on the output of the pan temperature detecting means 5, the pan heating means 4, the water tank heating means 7, and the on-off valve 1
An on-off valve control means 11 for controlling 0 is provided.

The operation of the above configuration will be described. Rice for cooking rice and water corresponding to the amount of the rice are put in a pan 2 and the main body 1 is placed in a predetermined state. Further, when a predetermined amount of water is put in the water tank 6 provided in the main body 1 and the user operates a rice cooking start switch (not shown), the rice cooking process is performed.
The rice cooking process is largely divided into the steps of flooding, cooking and steaming. In each process, the state of water and rice in the pot 2 is maintained at a temperature set as an appropriate value and for a predetermined time. Therefore, the pot heating means 4 and the water tank heating means 7 are driven while detecting the output of the pot temperature detecting means 5.

By driving the water tank heating means 7, the water in the water tank is heated and steam is generated. This steam moves in the steam pipe 8 and is discharged into the pot 2 from a part of the upper surface of the pot 2. The water and rice in the pot 2 are heated by the pot heating means 4 from the bottom of the pot 2, and further the top surface is heated by the steam discharged to the pot 2. By using steam as a heating source from the upper surface, in the submersion step, the temperature rises uniformly and in a short time to a temperature at which gelatinization of rice does not start, as compared with the heating by the conventional pan heating means 4. By uniformly maintaining the whole rice in the pan 2 at a target temperature, the water absorption condition of the rice is uniform, and the amount of water necessary for cooking is absorbed in a short time. Also in the cooking process, the boiling point is uniformly reached in a short time.

Furthermore, while the boiling state in the cooking process is maintained, the liquid (oneba) in which starch is eluted from rice is discharged from the pan 2 in a state of volume expansion containing bubbles, so-called spillage. Is about to appear.
As a measure to prevent this spillage, by applying steam to the bed that expands above the pan 2, the bubbles contained in the bed are destroyed and volume expansion is suppressed.

Therefore, it is possible to prevent spillage without stopping the boiling state while maintaining the boiling. By preventing boil over while maintaining the boiling state, the progress of the gelatinization phenomenon that rice is heated while absorbing water and changes into cooked rice is not suppressed, and the cooked rice that has finished the cooking process has a higher gelatinization degree. Becomes

In the Murashiri process, the water put in the pan at the start of rice cooking is absorbed and evaporated by the rice, and almost disappears. However, a large amount of water tends to remain at the bottom of the pot 2. In order to remove the excess water and accelerate the gelatinization of rice, the pot 2 is also heated in the steaming process. However, since the water content is low, heating the rice from the bottom of the pan 2 will burn the rice near the heated surface of the pan 2.

Further, the rice on the upper surface of the pot 2 is easily dried because the evaporation of water is active. Therefore, by heating with steam from the top even in the steaming process,
It is possible to prevent a local temperature rise due to heating of the entire pot and drying of rice on the upper surface and the vicinity thereof.

In each process, the on-off valve 10 provided on the steam cylinder is opened and closed at appropriate times by the on-off valve control means 11. When closed, the injected steam cannot escape to the outside of the main body 1, increasing the chances of contact with the water rice, heating the water in a short time, and the heat of the steam to the inside of the rice layer after the water is exhausted. It is transmitted and can heat the whole more effectively.

Some rice cookers have a heating means for heating from the lid 3. However, the rice in the pan 2 is heated by heating a part of the lid 3 arranged on the upper surface of the pan 2. Therefore, the above-mentioned effect cannot be obtained because it is through the space above the pot. Even in the rice cooker having the lid heating means 12, the same effect can be obtained by disposing the configuration of the present invention. Also, by making the water tank 6 detachable, it becomes a form that is easier for the user to handle.

Further, the water tank heating means 7 can be used together with the pan heating means 4 as a heating means of the rice cooker, and the same effect as the above can be obtained. Further, when the lid heating means 12 is provided as shown in FIG. 2, the structure inside the lid 3 can be easily and particularly downsized.

Further, as shown in FIG. 3, a removable water tank 13 is arranged above the pan 2 and a removable water tank heating means 14 is provided in the lid to heat the removable water tank 13 and the removable water tank. The means 14 constitutes the steam generating means 39. In this configuration, the removable water tank 13
Since it is not necessary to provide the installation space for the inside of the lid 3,
The internal structure can be easily and miniaturized. In addition, the temperature of the water in the removable water tank 13 also rises as the temperature in the pot 2 increases, so that the heating efficiency of the removable water tank 13 also improves.

Further, since it becomes easy to move the pan 2 and the removable water tank 13 as a set, the operation of putting rice and water into the pan 2 can be completed in a series of flow, and the removable water tank of the user. The usability for 13 is also improved, and the effect of preventing forgetting to put water in the removable water tank 13 can be obtained.

(Second Embodiment) A second embodiment of the present invention will be described with reference to FIG. It is assumed that the extension steam pipe 15 that is expandable and contractable is added between the steam pipe 8 and the steam hole 9. In this case, after setting water and rice in the pan 2 and closing the lid 3, the extension steam pipe 15 reaches a predetermined length and the steam holes 9 are introduced into the layer of water and rice, and when rice cooking is completed, the initial stage is started. Since it moves to the upper surface of the rice when the lid 3 is opened / closed, the steam hole 9 does not come into contact with the opening / closing operation, and the opening / closing can be performed easily like the conventional rice cooker.

Further, as shown in FIG. 5, the extension steam pipe 1
After arranging the split steam pipe 16 in the pan instead of 5, the rice and water are set in the pan to dispose the steam hole 9 inside the layer of water and rice, and the steam pipe 9 is closed with the lid 3 closed. 8 has a structure in which steam is not leaked at the connecting portion.

The operation of the above configuration will be described. 4 and 5, the operation is as shown in the first embodiment, but the steam holes 9 are arranged in the water and the rice, and the steam is discharged from the positions, so that the stirring of the water is promoted by the bubbles of the steam. The temperature of water and rice is made uniform, and the water is also heated by bubbles, so the temperature rises rapidly. Further, even when the water in the pan 2 is reduced, the vertical movement of the water is promoted by the bubbles, so that the tendency of insufficient water absorption for rice in the upper part of the pan 2 and excessive water absorption in the lower part of the pan 2 can be alleviated.

In addition, the steam in the steaming step is released in the state where the water is exhausted, so that the excess water staying inside the rice layer is also discharged to the outside of the rice, while the rice in the pan 2 is discharged. Is heated more uniformly.

By combining with the structure for discharging steam from the upper surface of the pot 2 shown in the first embodiment, the pot 2 as described above is used.
In addition to the effect of uniformly heating the inside, the effect of preventing spillage in the cooking process is also obtained.

By making the water tank 6, the extension steam pipe 15 and the split steam pipe 16 detachable, the respective water tanks 6, the extension steam pipes 15, and the split steam pipes 16 can be easily cleaned and cleaned and handled easily.

(Embodiment 3) A third embodiment of the present invention will be described with reference to FIG. Similar to FIG. 1, reference numeral 1 shown in FIG. 6 shows the body of the rice cooker, which is internally provided with a removable pan 2. Further, a lid 3 that covers the upper surface of the pot 2 is installed so as to be openable and closable. Further, a pot heating means 4 for heating the pot 2 and a pot temperature detecting means 5 for detecting the temperature of the pot 2 are arranged inside the main body 1.
Further, the water storage section 17 is arranged inside the bottom of the pot 2. Further, a water storage unit heating means 18 for heating the water storage unit 17 is provided in the main body 1 which is substantially aligned with the outside of the pot 2 in which the water storage unit 17 is arranged. The water storage unit 17 and the water storage unit 18 constitute a steam generating means 40. Further, the water reservoir 17 is provided with holes 19 through which rice is not selectively passed.

The operation of the above configuration will be described. The user puts rice and water in the pan 2. At that time, water enters the water reservoir 17 arranged at the bottom of the pot 2 through the hole 19 regardless of how the user handles it. Therefore, the user can surely set the water used for heating the steam in the pan 2.
The pot 2 is placed in the main body 1 in a predetermined state and rice cooking is started. The rice cooking process proceeds, and the pan heating means 4 is controlled to boil the water in the pan 2 in the cooking process. In the meantime, by controlling the water storage unit heating means 18 to heat the water storage unit 17, the water in the water storage unit 17 is locally heated, and the water becomes steam and is discharged into the space where rice is present in the pot 2. It
Water is replenished from the outside of the water storage unit 17 as much as the water becomes steam.

Since the bubbles of the steam generated from the water storage unit 17 heat the water and rice in the pan 2 while contacting them, the temperature inside the pan 2 is kept uniform and in a short time as compared with the case where only the pan heating means 4 is used. It can be raised. Further, the cooking process is ended with water remaining in the water storage unit 17, and the steam is positively passed through the space with rice in the pot 2 by heating the water storage unit 17 again in the steaming process. The steam heats rice.

By arranging the water storage section 20 and the water storage section heating means 21 as shown in FIG. 7, in addition to uniform and short-time temperature rise by steam, steam is discharged to the upper part of the pot 2. Therefore, it is possible to take measures against spillage during the cooking process. In addition, since the water storage section 20 has a heat insulating structure for the portion in contact with rice, steam heating from the upper surface is possible by controlling the water storage section heating means 21 even in the water immersion step.

By making the water reservoirs 17 and 20 detachable, the respective water storage portions 17 and 20 can be easily cleaned, and are clean and easy to handle.

(Embodiment 4) A fourth embodiment of the present invention will be described with reference to FIG. Water tank 6 shown in FIG.
It has a steam heating means 22 for further heating the steam generated from. Further, it has a steam temperature control means 23 for controlling the steam heating means 22 in order to generate superheated steam at a temperature required for each of the steps of flooding, cooking and steaming.

The operation of the above configuration will be described. Figure 1
Similarly, the water in the water tank 6 is heated by the water tank heating means 7 to generate steam. The generated steam is further heated by the steam heating means 20 and becomes superheated steam exceeding 100 ° C. under normal pressure and is discharged into the pan 2. Since it has a higher heat energy than ordinary steam, it is possible to heat the inside of the pan 2 uniformly and for a short time. Further, the temperature of the superheated steam is further raised in the cooking process by the superheated steam control means 23, so that the temperature inside the pan 2 can be raised in a shorter time. Furthermore, in the steaming process, by controlling the temperature at which rice is not dried,
The rice can be heated in a short time without drying or burning the rice.

The pot heating means 4, the lid heating means 12, the water tank heating means 7, the removable water tank heating means, the water storage section heating means 18 and 21, and the steam heating means 22 described in Examples 1 to 4 are as follows: Similar effects can be obtained by heating means such as electric heater heating, induction heating, halogen heater heating, microwave heating, or gas heating.

[0045]

As described above, according to the present invention, the rice and water in the pot are heated from above, which is insufficient for heating.
In addition, the present invention provides a rice cooker that improves the taste by preventing the upper part from drying and realizes a small steam rice cooker.

[Brief description of drawings]

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

FIG. 2 is a sectional view of a rice cooker according to an embodiment of the present invention.

FIG. 3 is a sectional view of a rice cooker according to an embodiment of the present invention.

FIG. 4 is a sectional view of a rice cooker according to an embodiment of the present invention.

FIG. 5 is a sectional view of the rice cooker according to the embodiment of the present invention.

FIG. 6 is a sectional view of a rice cooker according to an embodiment of the present invention.

FIG. 7 is a sectional view of a rice cooker according to an embodiment of the present invention.

FIG. 8 is a sectional view of a rice cooker according to an embodiment of the present invention.

FIG. 9 is a sectional view of a conventional rice cooker.

[Fig. 10] Fig. 10 is a diagram showing changes in gelatinization degree in cooked rice

FIG. 11 is a cross-sectional view of conventional steamed rice.

[Explanation of symbols]

1 body 2 pots 3 lid 4 pan heating means 5 Pan temperature detection means 6 water tank 7 Water tank heating means 8 steam pipes 9 steam holes 10 open / close valve 11 Open / close valve control means 12 Lid heating means 13 Detachable water tank 14 Detachable water tank heating means 15 Extended steam pipe 16 split steam pipe 17 water reservoir 18 Water storage unit heating means 19 holes 20 water storage 21 Water storage unit heating means 22 Steam heating means 23 Steam temperature control means 38 Steam generating means

   ─────────────────────────────────────────────────── ─── Continued front page    (72) Inventor Yoji Uitani             1006 Kadoma, Kadoma-shi, Osaka Matsushita Electric             Sangyo Co., Ltd. (72) Inventor Akemi Fukumoto             1006 Kadoma, Kadoma-shi, Osaka Matsushita Electric             Sangyo Co., Ltd. (72) Inventor Kuniyuki Nakanishi             1006 Kadoma, Kadoma-shi, Osaka Matsushita Electric             Sangyo Co., Ltd. F-term (reference) 4B055 AA03 BA22 BA53 BA63 CA09                       CA22 CA73 CB08 CC28 CD02                       DB02 DB08 DB12 DB14 DB15                       EA03 GB08 GC14 GC16 GC24                       GD04

Claims (3)

[Claims] 1. A pot and a pot heating means for heating the pot,
A lid for covering the opening of the pot and steam generating means are provided, and the steam generating means has a water tank and an electromagnetic induction heating type water tank heating means, and throws steam into the pot from the opening of the pot. Rice cooker with a steam inlet. 2. The rice cooker according to claim 1, wherein the water tank is detachable. 3. The rice cooker according to claim 1, further comprising steam heating means for heating the steam generated from the steam generating means.