JP2005296688A - Rice cooker - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To solve the problem of being difficult to provide boiled rice further superior in an eating taste, by uniformly raising the temperature by heating the inside of a pot, only by heating from the pot bottom periphery in a rice cooker. <P>SOLUTION: The eating taste of the boiled rice in the whole pot can be further improved without causing boiling nonuniformity, by uniformly heating the inside of the pot by preventing drying, by discharging steam from an opening part of the pot. <P>COPYRIGHT: (C)2006,JPO&NCIPI

Description

  The present invention relates to a rice cooker.

  The structure of the conventional common rice cooker is shown in FIG. A pan 25 is detachably mounted in the main body 24, and an openable / closable lid 26 is provided to cover the top surface of the pan. A pot heating means 27 is disposed at the bottom of the pot 25 and a lid heating means 28 is disposed within the lid 26 in order to heat the rice and water in the pot 25. Further, in order to control the heating state of the cooked rice, a pan temperature detecting means 29 for detecting the temperature of the pot 25 and a lid temperature detecting means 30 for detecting the temperature of the upper surface of the pot 25 are arranged at the bottom of the pot 25. The control unit 31 operates the pan heating unit 27 and the lid heating unit 28 at appropriate times based on the detected temperatures of the pan temperature detection unit 29 and the lid temperature detection unit 30.

  The operation of the above configuration will be described. Put in the pot 25 the amount of rice to be cooked and water suitable for the amount of rice. The rice cooking process of a general rice cooker is classified into watering, cooking, and steaming processes, and rice is cooked through the above processes. When the user starts cooking, the control means 31 is necessary for the above-mentioned immersion, cooking and steaming of the rice and water in the pot 25 based on the temperature detected by the pot temperature detecting means 29 and the lid temperature detecting means 30. Maintain temperature and time.

  What showed the change of the gelatinization degree which shows the ratio which the rice in this rice cooking process changes to rice is FIG. It can be seen from FIG. 10 that in the cooking process for heating and boiling rice, the degree of gelatinization increases rapidly as the heating amount is increased. However, when the water in the pan 25 is exhausted and the cooking process is completed, the heating amount of the pan heating means 27 must be reduced in particular to avoid the cooked rice.

  There is steam rice cooking where rice is cooked while receiving moisture and heat under uniform conditions by placing rice in an atmosphere filled with steam.

  A rice cooker using steam is as shown in Japanese Patent Laid-Open No. 02-283328. The steam rice cooker shown in FIG. 11 is demonstrated. The main body 32 locks the rice cooking tray 33 in the vicinity of the center of the interior, and a partition plate 34 having a large number of holes through which rice grains cannot pass is provided at the bottom. A water supply shower 35 is provided in the upper part, and water is sprayed uniformly on the set rice grains. A steam supply unit 36 is provided in the lower part, and the water supplied from the water supply pump 37 is vaporized and the steam is injected from below.

  In the above configuration, rice is cooked while jetting steam from below and rice from above.

As described above, it is general that the rice grain becomes a very large apparatus for supplying water and heat.
Japanese Patent Laid-Open No. 02-283328

  In a general household rice cooker, a pan heating means arranged at the bottom of the pan to heat the rice and water in the pan is the main, and the heating means in the lid is the rice in the pan, the space above the water Therefore, proper heating is difficult. 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.

  Furthermore, in the steaming process, the heating amount of the pan heating means must be reduced in order to prevent the cooked rice from burning.

  Moreover, the steam rice cooking apparatus which solves the above subject needs the water supply hand which supplements the water | moisture content with which supply is insufficient with steam rice to a rice grain other than the steam which heats a rice grain. Accordingly, the steam rice cooker has a very complicated configuration and is difficult to apply as a home-use rice cooker.

  In order to achieve the above object, the present invention comprises a steam heating means for generating superheated steam exceeding 100 ° C. in the pan, and in the steaming step during cooking, the rice in the pan is heated from above by the superheated steam. To do.

  As described above, according to the present invention, the rice in the pot is heated from above, which is insufficient in the heating of water, and the upper portion is prevented from drying, so that the taste is very good and the small steam. The rice cooker which implements rice cooking is provided.

  The invention according to claim 1 of the present invention is a pan, a pan heating means for heating the pan, a lid covering the opening of the pan, and a steam heating means for generating superheated steam exceeding 100 ° C. in the pan. In the steaming step during cooking, the rice in the pan is heated from above by the superheated steam, and the heating of rice and water during cooking is supplemented from above. Furthermore, when steaming, the rice can be heated without scorching, and cooked rice with better taste can be obtained.

  Furthermore, the structure which generates the superheated steam exceeding 100 degreeC in a pan is provided, and the temperature supply of water and the energy supply at the time of steaming can be implemented efficiently compared with the steam of 100 degrees C or less.

(Example 1)
A first embodiment of the present invention will be described with reference to FIG. 1 shown in FIG. 1 shows the main body of a rice cooker, and is equipped with a detachable pan 2. Further, a lid 3 covering the upper surface of the pan 2 is installed so as to be freely opened and closed. A pan heating means 4 for heating the pan 2 and a pan temperature detecting means 5 for detecting the temperature of the pan 2 are arranged inside the main body 1. A water tank 6 is housed inside the main body 1, and 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 generation means 38. Further, the steam generation means 38 and a part of the upper surface of the pan 2 are connected by the steam pipe 8, and the opening on the upper surface of the pan 2 is defined as the steam hole 9. In addition, an open / close valve 10 is installed in a steam cylinder from which steam is discharged from the pan 2 to the outside of the main body 1. Furthermore, the main body 1 has a pot heating means 4, a water tank heating means 7, and an opening / closing valve control means 11 for controlling the opening / closing valve 10 based on the output of the pot temperature detection means 5.

  The operation in the above configuration will be described. Two pots of water corresponding to the rice to be cooked and the amount of the rice are put into a predetermined state of the main body 1. Furthermore, when a predetermined amount of water is put into a water tank 6 provided in the main body 1 and a user operates a rice cooking start switch (not shown), a rice cooking process is performed. The rice cooking process is largely divided into each process of soaking, cooking, and steaming. In each step, the temperature of the water and the rice in the pan 2 are maintained at a set temperature and a predetermined time as appropriate values. 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. When the water tank heating means 7 is driven, the water in the water tank is heated and steam is generated. The steam moves through the steam pipe 8 and is discharged from a part of the upper surface of the pot 2 into the pot 2. Water and rice in the pot 2 are heated from the bottom of the pot 2 by the pot heating means 4, and further, the upper surface is heated by the steam discharged to the pot 2. By using steam as a heating source from the upper surface, in the water immersion process, the temperature rises uniformly and in a short time to a temperature at which the gelatinization of rice does not start compared to the heating of the conventional pan heating means 4. By maintaining the whole rice in the pan 2 uniformly at a target temperature, the water absorption conditions of the rice are uniform, and the amount of water necessary for cooking is absorbed in a short time. Also in the cooking process, the boiling point is reached uniformly and in a short time. Furthermore, while the boiling state of the cooking process is maintained, a phenomenon in which the liquid (rice cake) from which the starch has been eluted from the rice is released from the pan 2 in a state of volume expansion including bubbles is likely to appear. To do. As a measure for preventing this spill, the foam contained in the pot is destroyed by applying steam to the pot that expands above the pan 2 to suppress volume expansion.

  Therefore, it is possible to prevent spilling without stopping the boiling state during the boiling maintenance. The ability to prevent spilling while maintaining the boiling state, the rice is heated while absorbing water and the progress of the gelatinization phenomenon that changes to cooked rice is not suppressed, and the cooked rice that has finished the rice cooking process has a higher degree of gelatinization It becomes.

  Moreover, in the unevenness 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 lot of moisture tends to remain at the bottom of the pot 2. In order to remove the excess moisture and promote gelatinization of the rice, the pan 2 is also heated in the steaming process. However, since there is little moisture, the rice near the heated surface of the pan 2 will be burnt when heated from the bottom of the pan 2. In addition, the rice on the upper surface of the pan 2 is easily dried because moisture is actively evaporated. Therefore, by heating with steam from the upper surface also in the steaming step, it is possible to prevent a local temperature rise in the heating of the entire pan and drying of the rice in the upper surface and the vicinity thereof.

  In each step, the on-off valve 10 provided in the steam cylinder is opened and closed at appropriate times by the on-off valve control means 11. When the steam is closed, the steam that has been thrown in cannot escape to the outside of the main body 1, so the chance of contact with the paddy rice increases, the water heats in a short time, and the heat of the steam reaches the inside of the rice layer after the water runs out. The whole can be heated more effectively.

  Some rice cookers have 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 effect as described above cannot be obtained because the space is on the upper surface of the pan. In the rice cooker having the lid heating means 12, the same effect can be obtained by arranging the configuration of the present invention. Moreover, it becomes a form which a user can handle more easily by making the water tank 6 detachable.

  Moreover, it is possible to use the water tank heating means 7 together with the pot heating means 4 as a heating means of the rice cooker, and the same effects as those described above can be obtained. In addition, when the lid heating means 12 is provided as shown in FIG. 2, the configuration inside the lid 3 can be easily and miniaturized. Furthermore, as shown in FIG. 3, a removable water tank 13 that is detachable is disposed above the pan 2, and a removable water tank heating means 14 is provided in the lid. The removable water tank 13 and the removable water tank heating means 14 The steam generating means 39 is constituted. In this configuration, it is not necessary to provide the installation space for the removable water tank 13 in the lid 3, so that the configuration in the lid 3 can be more easily and miniaturized. In addition, since the temperature of the water in the detachable water tank 13 rises as the temperature in the pan 2 rises, the heating efficiency of the detachable water tank 13 is also improved. Moreover, since it becomes easy to move the pan 2 and the detachable water tank 13 as a set, the operation of putting rice and water into the pan 2 can be completed in a series of flows, and the user can use the detachable water tank 13 with ease. And the effect of preventing forgetting to put water into the detachable water tank 13 is also obtained.

(Reference Example 1)
A first reference example of the present invention will be described with reference to FIG. It is assumed that a stretchable extension steam pipe 15 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 becomes a predetermined length, the steam hole 9 enters the inside of the water and rice layer, and when the rice cooking is completed, When the lid 3 is opened and closed, it moves to the upper surface of the rice, so that the steam hole 9 is not in contact with the opening and closing operation, and can be easily opened and closed like a conventional rice cooker.

  Furthermore, as shown in FIG. 5, after arranging the divided steam pipe 16 in the pan instead of the extension steam pipe 15, the steam hole 9 is placed in the water and rice layers by setting rice and water in the pan. It is arranged and connected to the steam pipe 8 with the lid 3 closed, so that the steam does not leak 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. However, since the steam hole 9 is disposed in the water and the rice, and the steam is discharged from the position, stirring of the water is promoted by the bubbles of the steam. The entire temperature of water and rice is made uniform, and water is also heated by bubbles, so the temperature rises at a high speed. Furthermore, 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 with respect to the rice above the pan 2 and excessive water absorption below the pan can be alleviated.

  In addition, the steam in the steaming process is released in a state where there is no water, so that the excess moisture staying inside the rice layer is released together with the rice, and the rice in the pan 2 is more uniform. To be heated.

  In addition to being able to obtain the effect of uniformly heating the inside of the pan 2 as described above by using in combination with the configuration for releasing steam from the upper surface of the pan 2 shown in Example 1, the effect of preventing spillage in the cooking process. Can also be obtained.

  In addition, by making the water tank 6, the extended steam pipe 15, and the divided steam pipe 16 detachable, cleaning of each becomes easy, and it becomes clean and easy to handle.

(Reference Example 2)
A second reference example of the present invention will be described with reference to FIG. As shown in FIG. 1, 1 shown in FIG. 6 indicates the main body of the rice cooker, and includes a detachable pan 2. Further, a lid 3 covering the upper surface of the pan 2 is installed so as to be freely opened and closed. A pan heating means 4 for heating the pan 2 and a pan temperature detecting means 5 for detecting the temperature of the pan 2 are arranged inside the main body 1. Furthermore, the water storage part 17 is arrange | positioned inside the pot 2 bottom part inside. Moreover, it has the water storage part heating means 18 which heats the water storage part 17 in the main body 1 substantially coinciding with the pot 2 outside where the water storage part 17 is arranged. The water storage part 17 and the water storage part 18 constitute a steam generating means 40. Further, the water reservoir 17 is provided with a hole 19 through which rice is not selectively passed.

  The operation of the above configuration will be described. The user puts rice and water into the pan 2. At that time, water enters the water storage portion 17 disposed at the bottom of the pan 2 regardless of how the user handles the water. Therefore, the user can reliably set the water used for steam heating in the pan 2. The pot 2 is installed in a predetermined state of the main body 1 and rice cooking is started. A rice cooking process advances and the pot heating means 4 is controlled in order to boil the water in the pot 2 in a cooking process. Meanwhile, by controlling the water reservoir heating means 18 to heat the water reservoir 17, the water in the water reservoir 17 is locally heated, and the water becomes steam and is discharged into the space where rice is present in the pan 2. The The water is replenished from the outside of the water storage unit 17 as much as the water becomes steam.

  Since the steam bubbles generated from the water storage section 17 are heated while in contact with the water and rice in the pot 2, the temperature in the pot 2 can be raised uniformly and in a short time compared to heating by the pot heating means 4 alone. It is something that can be done. Furthermore, the cooking process is completed with water remaining in the water storage unit 17, and in the steaming process, the water inside the water storage unit 17 is heated again, so that steam actively passes through the space in the pot 2 with rice. The rice is heated by steam.

  In addition, by arranging the water storage unit 20 and the water storage unit heating means 21 as shown in FIG. 7, in addition to uniform and short-time temperature rise by steam, steam can be released to the upper part in the pan 2, It is possible to take measures against spillage during the cooking process. Moreover, in the water storage part 20, by having a heat insulation structure with respect to the part which contact | connects rice, the steam heating from the upper surface is also attained by controlling the water storage part heating means 21 also in a water immersion process.

  In addition, by making the water storage parts 17 and 20 detachable, cleaning of each becomes easy, and it becomes clean and easy to handle.

(Example 2)
A second embodiment of the present invention will be described with reference to FIG. Steam heating means 22 for further heating the steam generated from the water tank 6 shown in FIG. 8 is provided. Furthermore, it has the steam temperature control means 23 which controls the steam heating means 22 in order to produce | generate the superheated steam of the temperature required with respect to each process of immersion, cooking, and steaming.

  The operation of the above configuration will be described. As in FIG. 1, 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. at normal pressure and discharged into the pan 2. Since it has higher thermal energy than ordinary steam, heating in the pan 2 can be performed uniformly and for a short time. Moreover, the temperature rise in the pan 2 in a shorter time can be achieved by further increasing the temperature of the superheated steam with respect to the cooking process by the superheated steam control means 23. Further, in the steaming step, the rice can be heated in a short time without drying and further scorching by controlling the temperature to such a level that the rice is not dried.

  In addition, the pan heating means 4, the lid heating means 12, the water tank heating means 7, the detachable water tank heating means, the water reservoir heating means 18, 21 and the steam heating means 22 described in the first and second embodiments are heated by an electric heater. The same effect can be obtained in heating means such as induction heating, halogen heater heating, microwave heating, or gas heating.

Sectional drawing of the rice cooker in the Example of this invention Sectional drawing of the rice cooker in the Example of this invention Sectional drawing of the rice cooker in the Example of this invention Sectional drawing of the rice cooker in the reference example of this invention Sectional drawing of the rice cooker in the reference example of this invention Sectional drawing of the rice cooker in the reference example of this invention Sectional drawing of the rice cooker in the reference example of this invention Sectional drawing of the rice cooker in the Example of this invention Cross section of conventional rice cooker Change of gelatinization degree in cooked rice Cross section of conventional steam rice

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Main body 2 Pan 3 Lid 4 Pan heating means 5 Pan temperature detection means 6 Water tank 7 Water tank heating means 8 Steam pipe 9 Steam hole 10 On-off valve 11 On-off valve control means 12 Lid heating means 13 Removable water tank 14 Removable water tank heating Means 15 Extended steam pipe 16 Divided steam pipe 17 Water storage section 18 Water storage section heating means 19 Hole 20 Water storage section 21 Water storage section heating means 22 Steam heating means 23 Steam temperature control means 38 Steam generating means

Claims (1)

In the steaming step during cooking rice, a pan, a pan heating means for heating the pan, a lid covering the opening of the pan, and a steam heating means for generating superheated steam exceeding 100 ° C. in the pan, A rice cooker that heats the rice in the pot from the top surface with superheated steam.

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