JP2909795B2 - Insulated rice cooker - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an insulated rice cooker of the type in which an inner pot and rice cooked therein are kept warm.
The present invention relates to an insulated rice cooker that achieves a rapid temperature drop to an insulated temperature.

[0002]

2. Description of the Related Art As shown in FIG. 5, for example, a conventional insulated rice cooker includes a main body 1 and an openable and closable lid 2 for covering an upper opening of the main body 1. As shown in FIG. A rice cooker 3, an inner cooker 4 removably accommodated in the rice cooker 3,
A rice cooker sensor 5 in contact with the inner pot 4, a rice cooker 6 for heating the inner cooker 4 at the time of cooking rice, and a side heat retaining heater 7 operating at the time of steaming rice and keeping the temperature warm are provided respectively.

Among them, a rice cooker sensor 5 and a rice cooker heater 6
Are disposed in the rice cooker 3, and the side heaters 7 are disposed on the outer peripheral side of the rice cooker peripheral wall. A heat insulating material 8 made of glass wool or the like for preventing heat dissipation is provided on the inner surface of the peripheral wall of the vessel main body 1 facing the outer peripheral surface of the rice cooker 3 with a gap.
Is fixed.

On the other hand, the lid 2 is provided with an inner lid 9 for opening and closing the upper opening of the main body 1 and an inner lid provided below the inner lid 9 for opening and closing the upper opening of the inner hook 4. 10 and inner lid 9
And an outer lid 11 provided so as to surround the upper surface.

A heat insulating material 8 is provided in a hollow portion formed by the outer lid 11 and the inner lid 9, and a lid heat retaining heater for heating the lid 2 is provided on the upper surface of the inner lid 9. 12 is provided so as to be embedded in the heat insulating material 8. 13
Is an electronic circuit unit as control means provided inside the container body 1.

In such a conventional configuration, the rice cooker 6 heats the inner pot 4 during rice cooking. In addition, at the time of keeping the temperature after the completion of the rice cooking, once all the heaters 7
The power supply 12 is turned off, and the power cut-off state is continued until the temperature detected by the rice cooking sensor 5 decreases to a predetermined temperature.

Thereafter, the rice cooker 6 heats the inner pot 4 and the lid heat retaining heater 12 heats the lid 2 to maintain the cooked rice at a constant heat retaining temperature. At the time of cooking and keeping the temperature, the electronic circuit unit 13 controls the inputs of the rice cooking heater 6 and the lid heating heater 12 based on the temperature data obtained from the rice cooking sensor 5.

[0008]

By the way, after the completion of rice cooking, as described above, all the heaters 6, 7, 12 are cut off, and the temperature of the rice in the inner pot 4, the main body 1 and the lid 2 is reduced. Although it gradually descends, it takes a long time to reach the heat retention temperature level, so that undesired phenomena such as increased dew condensation on the inner surface of the lid 2 and drying of the rice surface may occur, and If the time of the high temperature state is prolonged from the end of rice cooking to the time when the temperature is lowered to the heat retaining temperature, dryness of rice and undesired odor may occur.

Further, even after the rice cooking is completed, the rice in the inner pot 4 is heated more than necessary by the heat retaining operation of the side heat retaining heater 7 and the lid heat retaining heater 12, so that the temperature is longer than the heat retaining temperature for a long time. There is a problem that the temperature is maintained, dryness and deterioration progress, and further, an unpleasant odor accumulated in the inner pot 4 during the long-time heat retention increases gradually.

As a measure for solving such a problem, Japanese Patent Application Laid-Open No. Hei 4-309308, which is a first prior art example, dispenses with a heat insulating material such as glass wool provided in the main body of the vessel and cuts off the heater. By promoting the temperature drop of cooked rice and the main body of the cooked rice, the time from the end of cooking to the start of heating to keep warm is shortened, thereby reducing the amount of dew condensation and dryness and deterioration of rice. Which is intended to suppress the above is disclosed.

A second prior art example is disclosed in Japanese Unexamined Patent Publication No.
Japanese Patent Publication No. 307010 discloses a method in which a fan is provided in a lid body, and after the rice is cooked by the fan, heat and steam in a vessel body are forcibly exhausted to the outside, thereby shortening a temperature drop time to a heat retaining temperature. Is disclosed.

However, in the case of the first prior art example,
It is a configuration where the heat insulation material is not provided in the container body,
Since the cooling of rice or the like after the heater is cut off is not positively performed, some unpleasant odor and the like remain, and the time required to reach the heat retention temperature cannot be said to be sufficient. On the other hand, in the case of the second prior art example, during the heat insulation, the fan provided in the lid body forcibly discharges all the odors accumulated in the main body, so that the preferable odor of the rice is also discharged together with the bad odor. Inconvenience occurs.

SUMMARY OF THE INVENTION The present invention has been made to solve the above-mentioned problems, and it is an object of the present invention to provide an insulated rice cooker capable of rapidly decreasing its temperature to an insulated temperature while leaving a favorable smell of rice after cooking. It is intended to provide.

[0014]

Means for Solving the Problems In order to achieve the above object, in a heat-retaining rice cooker according to the present invention, a rice cooker having a heating means for rice cooking in a container body whose upper opening is covered by a lid that can be opened and closed. An inner pot, which is removably accommodated in the rice cooker, a heating means for keeping warm, a cooling fan and a control means, and between the outer peripheral surface of the rice cooker and the inner peripheral surface of the container body. A cylindrical heat-insulating reflector is provided, a cool air suction hole is formed in the center of the bottom wall of the vessel, and a discharge hole is formed in the outer periphery of the bottom wall of the vessel. An outlet hole is formed in the bottom wall portion of the rice cooker, and a vent hole is formed in the upper portion of the peripheral wall of the rice cooker.

The outside air introduced from the cool air suction hole is directed upward from the blow hole, and forms an air passage for ventilating the air hole through a gap formed between the rice cooker and the inner pot. An exhaust path is formed in which exhaust gas discharged from the ventilation hole is directed downward and discharged to the discharge hole via a gap formed between the heat insulating reflector and the rice cooker.
Further, the control means activates the cooling fan immediately before or immediately after the completion of the rice cooking to cool the rice to the heat retaining temperature.

In the above structure, preferably, two or more air holes are provided, each air hole is formed in a louver shape, and the rice cooker above the heating means provided on the outer peripheral surface of the rice cooker peripheral wall. On the other hand, two or more outlets are provided at the peripheral wall portion of the shuttle and each outlet is formed in a louver shape.

Further, a shielding rib is provided between the lowest portion of the main body of the rice cooker and the bottom wall of the rice cooker which is in close contact with the rice cooker stand, and separates a cold air intake hole and a discharge hole. It is desirable to interpose a saucer between them.

[0018]

According to the above arrangement, after the rice cooking operation is completed, the outside air is forcibly introduced into the ventilation path from the cold air suction hole at the bottom of the main body by the operation of the cooling fan after the rice cooking operation. The rice is cooled rapidly to the warming temperature. For this reason, the start of the heating operation by the heating means is started early. Therefore, the time from the start of heat retention to the start of heating for heat retention is significantly reduced as compared to the conventional example,
The amount of condensation on the inner surface of the lid decreases.

[0019] Further, since the temperature drop after rice cooking is rapidly performed, it is not necessary to constantly energize the heat retaining heating means during the period from the start of the heat retention to the temperature retention to prevent dew condensation. Drying of the surface is effectively suppressed, and after the rice is cooked, the rice is rapidly cooled to the heat retaining temperature, so that dryness, alteration and unpleasant odor of the rice are suppressed, and a preferable odor is left as much as possible. it can.

[0020]

An embodiment of the present invention will be described below with reference to the drawings. FIG. 1 is a cross-sectional view of the insulated rice cooker according to the present embodiment, and FIG. 2 is a bottom view thereof. As shown in these figures, the insulated rice cooker according to the present embodiment includes a short-bottomed cylindrical main body 1 and an openable / closable lid 2 that covers an upper opening of the main body 1. .

In the vessel main body 1, a rice cooker 3 is provided.
An inner pot 4 which is removably accommodated in the inner pot 4, a rice cooker sensor 5 in contact with the inner pot 4, a rice cooker 6 as a heating means for rice cooker for heating the inner pot 4 at the time of cooking rice, and a heat insulator which operates during steaming and keeping the rice cooked. Side heaters 7 are provided as heating means. Among them, the rice cooker sensor 5 and the rice cooker 6 are respectively disposed in the rice cooker 3, and the side warming heater 7 is disposed on the outer peripheral side of the rice cooker peripheral wall.

The lid 2 includes an inner lid 9 that covers the upper opening of the container body 1 so as to be openable and closable, and an inner lid 10 that is provided below the inner lid 9 and that opens and closes the upper opening of the inner pot 4. , An outer lid 11 provided so as to surround the upper surface of the inner lid 9. Further, a heat insulating material 8 is provided in a hollow portion formed by the outer lid 11 and the inner lid 9, and a lid heater 12 for heating the lid 2 is provided on the upper surface of the inner lid 9. Lumber 8
It is attached so that it can be embedded in

Reference numeral 13 denotes an electronic circuit unit serving as a control means provided inside the main body 1, which operates a cooling fan 16 to be described later immediately before or immediately after the completion of rice cooking to keep the rice in the inner pot 4 warm. Control such as cooling to the temperature is performed.

In the upper part of the peripheral wall of the rice cooker 3 serving as information of the side heat retaining heater 7, ventilation holes 14 are provided in three upper and lower stages, and a blowout hole 15 is provided in the center of the bottom wall of the rice cooker 3. Further, a cooling fan 16 for cooling the rice cooker 3 is provided directly below the blowout hole 15.

A plurality of fan-shaped cool air suction holes 17 are formed over the entire circumference at the center of the bottom wall of the main body 1 below the cooling fan 16, whereby the cooling fan is formed. The outside air forcedly introduced from the cold air suction hole 17 by the driving of the air suction 16 flows upward from the blowout hole 15, and passes through the gap G ₁ formed between the rice cooker 3 and the inner cooker 4 to the ventilation passage S _1. Is configured.

If a tray 18 is interposed between the outlet 15 and the cooling fan 16, water drops adhering to the outer periphery of the inner pot 4 after washing the rice are received by the tray 18 and blown out. Drive motor 16a for cooling fan 16 through hole 15
Can be surely prevented from entering the vehicle, whereby the failure of the drive motor 16a can be prevented as much as possible.

A cylindrical heat-insulating reflector 19 is provided between the inner peripheral surface of the main body 1 and the outer peripheral surface of the rice cooker 3, and a fan-shaped outer peripheral portion of the bottom wall of the main body 1 is provided. Are formed over a half circumference. further,
And the gap G ₂ is formed between the heat insulating reflector 19 and cooking pot 3, the exhaust gas thereby downwardly exhaust discharged from the vent hole 14 is discharged to the discharge hole 20 through the gap G ₂ path S ₂ is configured.

In the main body 1 in which the ventilation path S ₁ and the exhaust path S ₂ are formed in series as described above, the cooling fan 16 operates immediately before or immediately after the completion of rice cooking, and the cooling fan 16 is connected to the cooling air suction hole 17. Outside air is introduced. This outside air passes through the outlet 15 of the rice cooker 3 via the cooling fan 16, and goes upward through the gap G ₁ between the inner cooker 4 and the rice cooker 3.
And the heated rice cooker 3 is cooled. When the rice cooker 3 is cooled, the inside air that has become warm is exhausted by the exhaust passage S _2.
Through the discharge hole 20.

[0029] In this embodiment, the exhaust passage S to ₂ inside air warmed discharged through do not mix with the cold outside air through the air passage S _1, cold air suction port 17 provided in the bottom wall of the vessel main body 1
A shielding rib 21 is provided at the boundary between the first and second discharge holes 20 to separate them from each other. The shielding rib 21 is provided between the lowest portion of the main body 1 that is in close contact with the rice cooker table 22 and the bottom wall of the rice cooker 3, and as shown in FIG. Are formed in an Ω-shape.

In order to make it difficult for radiant heat reflected from the inner pot 4 to escape from the vent 14 and the outlet 15 provided in the rice cooker 3, the vent 14 and the outlet 15 are formed in a louver shape. , To improve the heat retention capacity.

Next, the operation of the above configuration will be described.
After putting the washed rice and water into the inner pot 4 and pressing a rice cooker operation button (not shown), rice cooking is started, and the rice cooker 6 heats the inner pot 4. When the required time has elapsed and the rice is cooked, the temperature of the inner pot 4 reaches the operating point of the rice cooker sensor 5. The electronic circuit unit 13 inputs and controls the driving motor 16a so that the cooling fan 16 operates immediately before or immediately after the end of the rice cooking. After the rice cooking, all the heaters 7 and 12 are temporarily cut off.

Then, by driving the cooling fan 16,
The outside air reaches the outlet 15 from the cool air inlet 17 via the fan 16, and further has an air passage S ₁ between the rice cooker 3 and the inner cooker 4.
Through the vent hole 14. At this time, the outer surface of the inner pot 4 and the inner surface of the rice cooker 3 that have become hot during the rice cooking are rapidly cooled. The warmed inside air is discharged from the vent hole 14 to the exhaust passage S _2.
Is discharged to

When the temperature sensed by the rice cooker sensor 5 drops to a predetermined temperature, the rice cooker 6 heats the inner pot 4 and the lid heater 12 heats the lid 2 to cook the cooked rice. Is kept at a constant warming temperature.
At the time of cooking and keeping warm, the electronic circuit unit 13
, The input of the rice cooker 6 and the lid heater 12 is controlled based on the temperature data obtained from the rice cooker sensor 5.

In FIG. 3, the horizontal axis is the time axis, and the vertical axis is the average temperature axis in the inner pot 4. From the start of the rice cooking to the start of the heat retention, the immersion process, the main rice cooking process, the steaming process, and the heat retention process are performed. The temperature change in the shuttle 4 is shown. As shown in this figure, a soaking operation for about 8 minutes is performed at the beginning of the rice cooking, and in the soaking operation, for example, only for 3 minutes, only the rice cooking heater 6 is energized, and the rice cooker 3 is heated. For 5 minutes, all the heaters 6, 7, 12 are turned off.

After the immersion cooking operation, the main rice cooking operation is performed, and from the start of the main rice cooking operation, the rice heating heater 6, the lid warming heater 12, and the side warming heater 7 are continuously energized. After the inside is brought into a boiling state, the rice cooker 6 is intermittently energized at an energization rate of 50%. On the other hand, the electronic circuit unit 13 determines, for example, a time point at which five minutes have passed since the temperature detected by the air temperature sensor 26 reached 95 ° C., as a boiling time point.

When the temperature of the rice cooking sensor 6 reaches 120.degree. C. during the intermittent energization of the rice cooking heater 6, it is determined that the rice has been cooked, and thereafter, the operation shifts to the steaming operation. The steaming operation is performed, for example, for 15 minutes. During that time, the rice cooker 6 is temporarily energized to cook twice and heat.

On the other hand, during the steaming operation, the lid heater 12
The side heater 7 is intermittently energized at an energization rate of 50%, and heats the inner pot 4 and the lid 2. At the same time as the completion of rice cooking, the cooling fan operates for about 12 minutes to rapidly cool the rice cooker 3.
In this case, the operation may be started immediately before the end of rice cooking. During the operation of the fan 16 for about 12 minutes, the lid insulation heater 12 and the side insulation heater 7 are turned off, but after the fan operation is completed, the intermittent energization control is performed again to reduce the temperature of the inner pot 4 in the kept state to 73 ° C. Secured.

FIG. 4 is a characteristic diagram of a conventional example for comparison with this embodiment. In the control example shown outside this figure, as is apparent from comparison with the characteristics of the present embodiment shown in FIG. 3, in the present embodiment shown in FIG.
While the high temperature of not less than ° C. is intermittently secured for a sufficient time, the control example of FIG. 4 shows a tendency that the rice temperature in the inner pot 4 gradually decreases during the steaming period.

Therefore, in the present invention, steaming is sufficiently performed,
The rice is pregelatinized sufficiently. The time required to reach the heat retention temperature of 73 ° C. is about 20 minutes (T ₂ ) in the present embodiment of FIG. 3, while it takes more than 2 hours (T ₁ ) in the control example of FIG. As is clear from this, it can be seen that the present embodiment rapidly drops to the heat retention temperature of 73 ° C. as compared with the conventional example.

As described above, in this embodiment, since the temperature of the rice quickly decreases to the heat retaining temperature, the heating by the lid warming heater 12 and the side warming heater 7 starts early, and the amount of dew condensation on the inner surface of the lid 2 is increased. And drying of the rice surface is suppressed as much as possible. In addition to this, dryness of rice and unpleasant odor due to the Maillard reaction are effectively suppressed.

[0041]

As described above, according to the present invention, by operating the cooling fan provided in the main body immediately before or immediately after the completion of rice cooking, the outside air introduced from the cool air suction hole flows upward from the blow hole. To the air hole through the gap formed between the rice cooker and the inner pot, and the exhaust discharged from the air hole goes downward, and is discharged through the gap formed between the heat insulating reflector and the rice cooker. It is configured to be discharged to the hole, so that the temperature of the rice in the inner pot is forcibly cooled to the heat retention temperature, so that the heating means for rice cooking is cut off and the heating means for heat retention is energized. And the amount of dew condensation on the inner surface of the inner pot is reduced.

Further, in order to prevent dew condensation, there is no need to turn on the lid heat retaining heater from the start of the heat retention until the temperature reaches the temperature of about 73 ° C., so that the drying of the rice surface can be suppressed. , Thirst, deterioration and unpleasant odor can be suppressed.

According to the second or third aspect, since each of the plurality of ventilation holes or blowout holes is formed in a louver shape, the heat radiation from the rice cooker is suppressed as much as possible, and the heat retaining ability is improved.

According to the fourth aspect of the present invention, a shielding rib is provided between the lowest portion of the main body of the rice cooker and the bottom wall of the rice cooker that is in close contact with the rice cooker stand, and separates the cold air intake hole and the discharge hole.
Mixing of warm inside air discharged through the exhaust passage and cold outside air passing through the ventilation passage can be prevented, and thereby the cooling efficiency of rice by the outside air can be further improved.

According to the fifth aspect of the present invention, since the receiving pan is interposed between the blow-off hole and the cooling fan, water drops adhering to the outer periphery of the inner pot after washing the rice are received by the receiving pan. ,
It is possible to reliably prevent the cooling fan from entering through the blowout hole, thereby preventing the failure of the fan as much as possible.

[Brief description of the drawings]

FIG. 1 is a cross-sectional view showing one embodiment of a warm rice cooker according to the present invention.

FIG. 2 is a bottom view thereof.

FIG. 3 is a diagram showing the temperature change.

FIG. 4 is a diagram showing a temperature change of a conventional example which is comparatively symmetrical with the present embodiment.

FIG. 5 is a sectional view of a conventional example.

[Explanation of symbols]

REFERENCE SIGNS LIST 1 container body 2 lid 3 rice cooker 4 inner pot 6 rice cooker 7 side heater 12 lid heater 13 electronic circuit unit 14 ventilation hole 15 blowout hole 16 cooling fan 17 cool air suction hole 18 tray 19 heat insulating reflector 20 Discharge hole 21 Shield rib 22 Rice cooker stand G ₁ Gap between rice cooker and inner pot G ₂ Gap between heat insulating reflector and rice cooker S ₁ Vent path S ₂ Exhaust path

Claims (5)

(57) [Claims] 1. A rice cooker having an upper opening covered by an openable and closable lid, wherein the rice cooker has a heating means for cooking rice, and an inner cooker removably accommodated in the rice cooker. , A heating means for keeping warm, a cooling fan, and a control means are provided, and a tubular heat-insulating reflector is provided between an outer peripheral surface of the rice cooker and an inner peripheral surface of the container main body. A cool air suction hole is formed in the center of the bottom wall, and a discharge hole is formed in the outer peripheral portion of the bottom wall of the vessel, and a blowout hole is formed in a rice cooker bottom wall portion directly above the cooling fan. An air hole is formed in the upper part of the rice cooker peripheral wall, and the outside air introduced from the cool air suction hole flows upward from the blow hole, and passes through a gap formed between the rice cooker and the inner pot to the air hole. A ventilation path for ventilation is formed, and exhaust discharged from the ventilation hole is directed downward, An exhaust path for discharging to the discharge hole through a gap formed between the heat insulating reflector and the rice cooker,
In addition, the control means activates the cooling fan immediately before or immediately after the completion of the rice cooking to cool the rice to a heat retaining temperature. 2. A rice cooker peripheral wall portion which is provided with a plurality of air holes, each of which is formed in a louver shape, and which is located above the heat retaining heating means disposed on the outer peripheral surface of the rice cooker peripheral wall. The insulated rice cooker according to claim 1, which is provided. 3. The insulated rice cooker according to claim 1, wherein a plurality of blowout holes are provided, and each blowout hole is formed in a louver shape. 4. A heat retaining type according to claim 1, wherein a shielding rib for separating a cold air intake hole and a discharge hole is provided between a bottom portion of the rice cooker and a bottom portion of the rice cooker which is in close contact with the rice cooker table. rice cooker. 5. The insulated rice cooker according to claim 1, wherein a saucer is interposed between the outlet and the cooling fan.