JP2013102925A - Rice cooker - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a rice cooker that can cook rice deliciously in such a way that an upper surface of cooked rice is in a raised shape rather than flat without uneven cooking in a pan.SOLUTION: In a cooking step of heating the rice from a temperature lower than the gelatinization temperature of the rice to the boil, first, an annular-formed wall 2b causes a boil bubble 46 generated on a dimple 2a to rise inside the cooked rice to generate a steam hole in the substantially center of the rice 44. Thereafter even heating throughout the bottom of the pot allows the boil bubble 46 to rise along a pot surface where the bubble passes easily and in the center where the bubble is hard to pass, and the boil bubble 46 evenly rises throughout the pot 2 and thereby the cooked rice can be heated without uneven cooking. As a result, the rice cooker is provided which can cook rice deliciously in such a way that the upper surface of the cooked rice is in the raised shape rather than flat without uneven cooking.

Description

  The present invention relates to a rice cooker that controls bubbles at the time of boiling and is delicious evenly, and cooks the upper surface of the rice into a shape that is higher than flat.

  In a general rice cooker for home use, cooked rice is required to be cooked deliciously with little unevenness. Furthermore, it is considered that a visually delicious effect can be obtained by cooking in a shape that is higher than the flatness visually.

  Therefore, a rice cooker has been invented that can evenly cook the top surface of the rice without unevenness by forcibly removing the pressure increased during boiling in the pressure rice cooker to generate a bumping phenomenon and stirring the rice. (For example, refer to Patent Document 1).

  FIG. 5 is a side sectional view of a conventional rice cooker.

  In FIG. 5, 1 is a rice cooker body, 2 is a pan that is detachably mounted on the rice cooker body 1, and 3 is a lid that covers the upper surface of the pan 2 so that it can be opened and closed. 5a is a pan bottom surface heating coil for heating the pan 2 via the protective frame 9, and 5b is a pan side surface heating coil for heating the pan via the protective frame 9, and constitutes heating means. A ball 15 having a predetermined dead weight is placed so as to close the valve hole 4bb communicating with the pot 2. Reference numeral 10 denotes a steam cylinder for discharging steam from the inside of the pan 2 to the outside of the rice cooker body 1. Reference numeral 16 denotes a plunger composed of a rod 16a for pushing the ball 15 to connect the valve hole 4bb and the steam cylinder 10, and a cylinder 16b for controlling the pushing and pulling of the rod 16a.

  4a is an inner lid packing, 4c is a safety valve, and 4 is an inner lid. Reference numeral 6 denotes control means, which includes a heating control means 6a and a pressure control means 6b. Reference numeral 8 denotes a pan temperature detecting means for detecting the temperature of the pan 2. An operation input display unit 12 is formed on the lid 3.

  In the pressure rice cooker configured as above, when the rod 16a of the plunger 16 is pulled and the ball hole 15 is closed while the valve hole 4bb is closed, the inside of the pan 2 is brought into a boiling state according to the weight of the ball 15. Pressure is applied in the pan 2. Here, when the rod 15a is pushed to move the ball 15 and the valve hole 4bb communicates with the steam cylinder 10, the pressure in the pan 2 drops to atmospheric pressure, and a sudden boiling phenomenon occurs. Water is stirred. This is repeated several times while boiling continues.

  As described above, rice and water are agitated using the bumping phenomenon caused by raising and lowering the pressure to make the heat transfer uniform, and the top surface of the rice can be made flat.

Japanese Patent No. 4094023

However, in the configuration of the conventional rice cooker, the configuration of the pressure rice cooker is essential to cause bumping. In addition, by stirring the rice in a boiling process where the gelatinization of rice proceeds to some extent, the rice in a state where the paste-like surfaces are adhered to each other is peeled off, damaging the rice surface and damaging the appearance of the rice grains, There were problems such as nutrient spillage and loss of rice elasticity.

  An object of the present invention is to provide a rice cooker that does not require a pressure configuration, is evenly delicious without causing damage to the rice surface due to stirring, and cooks the top surface of the rice into a shape that is higher than flat. To do.

  The inventors of the present invention have found the following as a result of intensive studies to solve the conventional problems.

  That is, in order to apply heat uniformly to the rice, it is important that the boiling bubbles rising from the pan are brought into contact with the whole rice from the cooking process to the boiling process.

  In addition, when moving rice, such as stirring, the first half of the cooking process in which the rice surface is heated to a boiling state from the temperature below the gelatinization temperature of the rice is not the boiling process after the rice surface has been gelatinized. Less damage is preferable.

  Furthermore, it has been found that by controlling the position where bubbles rise from the cooking process to the boiling process, the shape of the cooking is greatly affected. Based on this finding, the present invention has been conceived.

  In order to solve the above-mentioned conventional problems, the rice cooker of the present invention is provided with a dimple shape that becomes a boiling core at the bottom of the pan, and a wall portion formed in an annular shape to raise bubbles generated in the dimple, It was set as the structure which produces | generates a crab hole in the approximate center part of the pan at the initial stage of a process.

  This makes it possible to bring the boiling bubbles into contact with the whole rice because the boiling bubbles rise not only from the pot skin where the boiling bubbles easily pass when the bottom of the pan is heated uniformly, but also from the central part where it is difficult to pass.

  The rice cooker of the present invention can heat the inside of the pan evenly by bringing the boil bubbles into contact with the whole rice without stirring due to the bumping phenomenon due to reduced pressure, deliciously, the shape where the upper surface of the rice is raised more than flat Can be cooked.

  Moreover, although rice is moved in order to produce | generate a crab hole, a rice grain surface is not damaged by producing | generating in the early stage of the cooking process in which gelatinization has not progressed.

Side sectional view of the rice cooker in Embodiment 1 of the present invention. The graph which shows the pan temperature at the time of the rice cooking of the rice cooker in Embodiment 1 of this invention. Operation | movement explanatory drawing explaining operation | movement of the rice cooker in Embodiment 1 of this invention. Operation | movement explanatory drawing explaining operation | movement of the rice cooker in Embodiment 1 of this invention. Side sectional view of a conventional rice cooker

1st invention is a rice cooker main body, the pan equipped to a rice cooker main body, the heating means which heats the said pan, the cover which covers a rice cooker main body, the pan temperature detection means which detects the temperature of the said pan, Heating control means for controlling the heating means according to a predetermined rice cooking sequence according to the output of the temperature detection means, the pan is provided with a plurality of dimples on the inner surface of the bottom, and the center of the pan is centered on the center side from the dimple formation portion As a structure to provide an annular wall part, the bubble generated in the dimples at the beginning of the cooking process for heating to a boiling state from a temperature below the gelatinization temperature of rice is raised at the wall part in the middle. After creating a crab hole in the part, by heating the whole pan bottom and raising the bubbles from the whole pan bottom, the boiling bubbles rise not only from the pot skin where boiling bubbles easily pass, but also from the central part where it is difficult to pass Whole rice It is possible to contact the boiling bubbles. Therefore, the inside of the pan can be heated evenly, and deliciously, the top surface of the rice can be cooked into a shape that is higher than flat.

  Moreover, although rice is moved in order to produce | generate a crab hole, a rice grain surface is not damaged by producing | generating in the early stage of the cooking process in which gelatinization has not progressed.

  In the second invention, in particular, since the dimple formation portion of the first invention is inclined from the dimple formation portion to the above, the bubbles generated in the dimple are reliably guided to the wall portion. After the crab hole is formed in the approximate center of the rice, the entire bottom of the pan is heated to raise the bubbles from the entire bottom of the pan. Since the bubbles rise, it becomes possible to bring the boiling bubbles into contact with the whole rice. Therefore, the inside of the pan can be heated evenly, and deliciously, the top surface of the rice can be cooked into a shape that is higher than flat.

  Moreover, although rice is moved in order to produce | generate a crab hole, a rice grain surface is not damaged by producing | generating in the early stage of the cooking process in which gelatinization has not progressed.

  In the third aspect of the invention, in particular, the heating means for heating the pot bottom of the first or second aspect of the invention comprises a pot bottom inner heating means and a pot bottom outer heating means, and each is configured to be able to control heating independently. By doing so, it becomes easy to concentrate heating when raising the bubbles, and it becomes easier to control the place where the crab holes are generated.

  And at the beginning of the cooking process for heating from the temperature below the gelatinization temperature of rice to the boiling state, the inside of the pan is heated intensively by the heating means inside the pan bottom, and the bubbles generated in the dimples rise at the wall After creating a crab hole in the approximate center of the rice, heat the entire pan bottom to raise the bubbles from the entire pan bottom, so that it boil not only from the pot skin where boiling bubbles easily pass, but also from the difficult center Since the bubbles rise, it becomes possible to bring the boiling bubbles into contact with the whole rice. Therefore, the inside of the pan can be heated evenly, and deliciously, the top surface of the rice can be cooked into a shape that is higher than flat.

  Moreover, although rice is moved in order to produce | generate a crab hole, a rice grain surface is not damaged by producing | generating in the early stage of the cooking process in which gelatinization has not progressed.

  In the fourth aspect of the invention, in particular, bubbles are generated by adopting a configuration in which the pot bottom inner heating means or the pot bottom outer heating means is disposed at a position that opposes the dimple shape of any one of the first to third inventions. In this case, it becomes easy to concentrate heating, and it becomes easy to control the place where the crab hole is generated.

  And at the beginning of the cooking process for heating from the temperature below the gelatinization temperature of rice to the boiling state, the inside of the pan is heated intensively by the heating means inside the pan bottom, and the bubbles generated in the dimples rise at the wall After creating a crab hole in the approximate center of the rice, heat the entire pan bottom to raise the bubbles from the entire pan bottom, so that it boil not only from the pot skin where boiling bubbles easily pass, but also from the difficult center Since the bubbles rise, it becomes possible to bring the boiling bubbles into contact with the whole rice. Therefore, the inside of the pan can be heated evenly, and deliciously, the top surface of the rice can be cooked into a shape that is higher than flat.

  Moreover, although rice is moved in order to produce | generate a crab hole, a rice grain surface is not damaged by producing | generating in the early stage of the cooking process in which gelatinization has not progressed.

  In the fifth aspect of the invention, in particular, the configuration is such that the dimples are not arranged on the center side of the pan relative to the wall portion of any one of the first to fourth aspects of the invention, thereby concentrating air bubbles too much in the center portion of the pan. And prevent large holes from opening in the rice.

  And at the beginning of the cooking process for heating from the temperature below the gelatinization temperature of rice to the boiling state, the inside of the pan is heated intensively by the heating means inside the pan bottom, and the bubbles generated in the dimples rise at the wall After creating a crab hole in the approximate center of the rice, heat the entire pan bottom to raise the bubbles from the entire pan bottom, so that it boil not only from the pot skin where boiling bubbles easily pass, but also from the difficult center Since the bubbles rise, it becomes possible to bring the boiling bubbles into contact with the whole rice. Therefore, the inside of the pan can be heated evenly, and deliciously, the top surface of the rice can be cooked into a shape that is higher than flat.

  Moreover, although rice is moved in order to produce | generate a crab hole, a rice grain surface is not damaged by producing | generating in the early stage of the cooking process in which gelatinization has not progressed.

  Hereinafter, embodiments of the present invention will be described with reference to the drawings. Note that the present invention is not limited to the embodiments.

(Embodiment 1)
FIG. 1 shows a side sectional view of a rice cooker according to the first embodiment of the present invention.

  In FIG. 1, the rice cooker main body 1 is formed in a substantially cylindrical shape having an open top surface, and a protective frame 9 that is a pot storage portion is disposed inside the rice cooker main body 1. The pot 2 having the water level line drawn on the inner peripheral surface is detachably disposed. A pan bottom heating coil 5a for heating the pan 2 is arranged outside the protective frame 9, and the pan bottom heating coil 5a is a pan bottom inner heating coil 5a-1 for heating the pan bottom inside and a pan bottom outside for heating the pan bottom outside. The heating coil 5a-2 can be controlled independently.

  In addition, a pan side heating coil 5 b is disposed outside the side surface of the pan 2. The pan bottom heating coil 5a and the pan side heating coil 5b may be heaters instead of the heating coils.

  A lid 3 is attached to the top of the rice cooker body 1 so as to be freely opened and closed. The lid 3 is rotatably supported on the rear portion of the protective frame 9 via a hinge shaft 3a and is urged by a rotating spring 3b. At the other end of the lid 3, a hook button 1 a pivotally supported in front of the protective frame 9 is disposed to prevent the lid 3 from being opened. When the hook button 1a is fitted to the lid 3, the lid 3 is held by the hook button 1a without opening and is in a closed state.

  An inner lid 4 having a steam port 4b for discharging steam generated in the pan 2 during rice cooking and heat insulation is disposed at the lower portion of the lid 3, and an inner lid heating that is a heater for heating the inner lid 4 is disposed on the upper portion. A cylindrical steam cylinder 10 communicating with the coil 5c and the outside of the main body is disposed. The pan bottom heating coil 5 a, the pan side heating coil 5 b and the inner lid heating coil 5 c are heating means 5.

  A steam port packing 7 is disposed between the steam cylinder 10 and the inner lid 4 to prevent steam from flowing into the lid 3. Further, an inner lid packing 4a that is in contact with the upper surface of the flange portion (not shown) of the pan 2 is disposed on the outer peripheral portion of the inner lid 4, and steam generated in the pan 2 during rice cooking and heat insulation is steamed. It prevents outflow from outside except 4b.

  The pan temperature detecting means 8 can detect the temperature of the pan 2 by heat conduction while being in contact with the substantially central portion of the bottom of the pan 2.

  It has a control means 6 for controlling the heating means 5 according to a predetermined rice cooking sequence according to the output of the pan temperature detecting means 8.

  About the rice cooker comprised as mentioned above, the operation | movement and an effect | action are demonstrated below.

  After the user puts rice to be cooked and water 45 corresponding to the amount of rice into the pan 2 and sets it in the rice cooker body 1 and closes the lid 3, the rice cooking start button (not shown) on the operation input display unit 12. The rice cooking process is carried out by operating.

  Here, FIG. 2 is a graph which shows the pan temperature at the time of rice cooking of the rice cooker in the 1st Embodiment of this invention. The rice cooking process is divided into pre-cooking, cooking, boiling, and murashi in order of time. In the pre-cooking process, the heating means 5 of the pot 2 is controlled so that the temperature of the pot 2 is equal to or lower than the gelatinization temperature of the rice and suitable for water absorption of the rice (for example, 60 ° C.). And heat.

  Next, in the cooking process, the pan 2 is heated with a predetermined amount of heat by the pan heating coil 5a until the temperature of the inner lid 4 reaches a predetermined value (for example, 80 ° C.). The amount of cooked rice is determined based on the temperature rise rate at this time.

  At this time, if many boiling bubbles rise from the bottom of the pan, a bubble passage (crab hole) is formed from the lower layer to the upper layer of rice, and the more the hole is, the better the center of the rice can be heated. In order to create a hole in this, in the cooking process, before the surface of the rice is gelatinized, a strong boil occurs in the early stage A (shown in FIG. 2), and the boiling bubbles before the rice joins each other. Need to be raised.

  Therefore, when the pot bottom heating coil 5a is divided into a pot bottom inner heating coil 5a-1 and a pot bottom outer heating coil 5a-2 so that it can be controlled independently, and only the pot bottom inner heating coil 5a-1 is energized, the entire pot bottom heating coil 5a is provided. Because it can be put in more power than energizing, it can cause a strong boiling locally.

  Here, FIG. 3 is a schematic diagram showing the state in the pot when only the pot bottom inner heating coil 5a-1 is energized in the stage A in the initial stage of the cooking process.

  In this case, the pot 2 can be concentrated and heated at the approximate center, and the bottom of the dimple 2a is slightly close to the pot bottom inner heating coil 5a-1, so that local boiling occurs and some of the generated boiling bubbles 46 are Ascending as it is, a part moves along the inclination toward the center of the pot along the pot skin, the surface tension is reduced by the annular wall 2b, and the boiling bubbles rise off the pot skin. The boiling bubbles 46 push the rice 44 away by the buoyancy and reach the water surface. At this time, a hole 41 is formed in the rice 44 at the passage of the boiling bubble 46.

  If there is no wall 2b, the boiling bubble 46 gathers at the center of the pan bottom and rises after growing into a large bubble, so a large hole is opened in the rice, and thereafter the bubble rises intensively and becomes local heating. End up. That is, the bubbling bubbles 46 are not concentrated in the center by the wall 2b, and a range for raising the bubbles uniformly is defined.

In consideration of care and the like, a configuration in which a dome-shaped convex portion is provided instead of providing the wall portion 2b is conceivable. In this case, the boiling bubble 46 generated in the dimple 2a toward the center is Overcoming the dome shape, the boiling bubble 46 concentrates in the center and grows into a large bubble, resulting in the same problem as when the wall 2b is not present.

  Further, in order not to concentrate the boiling bubbles 46 in the center, the dimples 2a are not arranged inside the wall 2b.

  Moreover, even when the pot bottom inner heating coil 5a-1 and the pot bottom outer heating coil 5a-2 cannot be independently controlled, the same effect can be expected only by local boiling weakening. A hole 41 can be created.

  Then, in the stage B (illustrated in FIG. 2) from the latter half of cooking to the boiling process, the bottom heating inner coil 5a-1 and the bottom outer heating coil 5a-2 are heated and controlled to a predetermined balance. The boiling bubble 46 is raised from the whole.

  Here, FIG. 4 is a schematic diagram showing a state in the pan when the pan bottom inner heating coil 5a-1 and the pan bottom outer heating coil 5a-2 are heated and controlled to a predetermined balance in the stage B from the latter half of the cooking process to the boiling process. is there.

  At this time, the boiling bubbles 46 rise in the vicinity of the pot skin where there is a certain gap between the rice 44 and the pot skin, and the boiling bubbles 46 also rise from the vicinity of the hole 41 in the central part generated in the stage A, The boiling bubble 46 can contact the whole rice. By heating the whole rice 44 by this, it can be cooked deliciously without unevenness.

  Further, the rice bubbles are gelatinized and swollen uniformly by the boiling bubbles 46, so that the upper surface of the rice is cooked into a shape that is higher than flat.

  By providing the dimple 2a at a position where it can be heated by the coils opposed to each other as described above, inclining so as to increase toward the center of the pan, and providing the wall portion 2b formed in an annular shape, the boiling bubble 46 in the first half of the cooking process The crab holes are formed by uniformly raising without concentrating them in the center, and the pot bottom inner heating coil 5a-1 and the pot bottom outer heating coil 5a-2 are brought to a predetermined balance in the boiling process from the latter half of the subsequent cooking process. By controlling the heating, the boiling bubbles 46 are uniformly raised from the entire bottom of the pan 2, and the whole rice is heated, and the top surface of the rice can be cooked into a shape that is more delicious than the flatness.

  Furthermore, the movement of the rice 44 by the buoyancy of the boiling bubbles 46 to generate the crab hole 41 is the initial stage of the cooking process before the gelatinization of the rice surface begins, so the rice grains are not joined together, and the rice surface It will not damage you.

  In addition, although the structure which divided | segmented the pot bottom heating coil 5a into the concentric circle shape was shown here, if it is the structure for raise | generating local boiling, it will not restrict | limit to this structure.

  As described above, by providing the pot bottom inner heating coil 5a-1 in order to generate a crab hole locally by strong heating by concentrated heating at the initial stage of the cooking process, boiling is performed from the latter half of the subsequent cooking process. When raising the boiling bubbles 46 uniformly from the bottom of the pan 2 in the process, the whole rice is heated by raising the boiling bubbles 46 not only near the pot skin but also around the crab hole 41, and is uniform and delicious. And the top surface of the rice can be cooked flat.

  Furthermore, the movement of the rice 44 by the buoyancy of the boiling bubbles 46 to generate the crab hole 41 is the initial stage of the cooking process before the gelatinization of the rice surface begins, so the rice grains are not joined together, and the rice surface It will not damage you.

  As mentioned above, since the rice cooker concerning this invention can control the boiling location in a pan, it can apply to the use of the automatic cooking which stirs an ingredient with the buoyancy of a boiling bubble by moving a boiling location.

DESCRIPTION OF SYMBOLS 1 Rice cooker main body 2 Pan 2a Dimple 2b Wall part 3 Lid 4 Inner lid 4a Inner lid packing 4b Steam port 5 Heating means 5a-1 Pan bottom inner heating coil 5a-2 Pan bottom outer heating coil 5b Pan side heating coil 5c Inner lid heating coil 6 Control means 7 Steam port packing 8 Pan temperature detection means 9 Protection frame 10 Steam cylinder 12 Operation input display part 41 Crab hole 44 Rice 45 Water 46 Boiling bubble

Claims (5)

The rice cooker body,
A pan equipped in the rice cooker body;
Heating means for heating the pan;
A lid covering the rice cooker body;
Pan temperature detecting means for detecting the temperature of the pan;
Heating control means for controlling the heating means according to a predetermined rice cooking sequence according to the output of the pan temperature detection means,
The cooker is characterized in that a plurality of dimples are provided on the inner surface of the bottom portion, and a wall portion formed in an annular shape centering on the center of the pan is provided on the center side of the dimple formation portion. 2. The rice cooker according to claim 1, wherein the wall portion is inclined from the dimple formation portion to the wall portion so as to be higher. The rice cooker according to claim 1 or 2, wherein the heating means for heating the pot bottom is constituted by a pot bottom inner heating means and a pot bottom outer heating means, and each can be controlled independently of heating. The rice cooker according to any one of claims 1 to 3, wherein the pot bottom inner heating means or the pot bottom outer heating means is arranged at a position opposite to the dimple shape. The rice cooker according to any one of claims 1 to 4, wherein the dimple is not disposed closer to the center of the pan than the wall portion.