JP3258541B2 - Jar 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 a jar rice cooker intended to improve the heat retention performance after cooking rice and to provide delicious rice even when kept warm for a long time.

[0002]

2. Description of the Related Art A conventional jar rice cooker has an inner pot housed in a main body, and a lid for covering upper openings of the main body and the inner pot.
The main body is provided with a main body heating means for heating the inner pan, a lid heating means for heating the lid on the lid, and a temperature adjusting means provided on the main body. And the rice is kept warm by keeping the lid at a substantially constant temperature. As an example of the method of temperature control by the temperature control means, a pot bottom temperature sensor which is thermally coupled to the bottom of the inner pot is provided at the bottom of the main body, and when the temperature of the pan bottom temperature sensor falls below a certain temperature, the main body heating means and the lid heating means are energized. When the temperature of the pan bottom temperature sensor rises above a certain temperature, energization is stopped to adjust the temperature, and the main body and the lid are each kept at a predetermined substantially constant temperature. By keeping the main body and the lid at a substantially constant temperature, the inner pot and the rice inside the inner pot are also kept at an appropriate temperature (for example, Japanese Utility Model Laid-Open No. 62-10012).
No. 6).

As a second example, a new lid temperature sensor is provided in the lid to suppress temperature unevenness and dew condensation on the lid. As in the first example, the temperature of the main body heating means is controlled by the output of the pan bottom temperature sensor. In some cases, the temperature of the lid heating means is adjusted independently by the output of the lid temperature sensor (see, for example, Japanese Utility Model Laid-Open No. 4-36922).

[0004]

In the first example in which the power control of the conventional main body heating means and the conventional lid heating means is synchronized to adjust the power to a predetermined control temperature, or a new lid sensor is provided in the lid. Also, in the second example in which the temperature of the lid heating means is independently controlled, the inner pan and the lid are each configured to regulate the temperature to a substantially constant temperature. The inner pot is stabilized at a predetermined substantially constant temperature and the lid is stabilized at a predetermined substantially constant temperature of the lid, and this stable state continues as long as the heat retention is continued.

However, it is very difficult to make the temperature of the inner pot and the lid substantially the same, and even if the same temperature is set, the heating amount (electric power) of the main body heating means and the lid heating means
The temperature difference occurs due to variations in the temperature of the pan bottom temperature sensor and the lid temperature sensor. In addition, there are temperature differences depending on the locations of the inner pot and the lid. For example, the temperature near the main body heating means of the inner pot is high, and the farther away it is, the lower it is.

The problem here is a phenomenon in which water evaporates from the rice during the heat retention, and the evaporated water condenses on low-temperature portions. If the temperature of the inner pot is lower than the temperature of the lid, moisture will condense on the inner pot, and the condensate will flow down along the inner pot side wall, causing the rice in contact with the inner pot side wall to get wet and break into a glue Occurs. Conversely, if the temperature of the lid is lower than the inner pot, dew forms on the lid, the dew drips from the lid on the rice surface, the rice surface becomes glued, and when the lid is opened, a large amount of dew water flows to the main body side There was a problem that it got into the inner pot or flowed to the top of the main unit and soiled.

[0007]

SUMMARY OF THE INVENTION The present invention has been made to solve the above problems, and has an inner pot housed in a main body, a lid for covering the upper opening of the main body and the inner pot, and Rice cooking heating means provided to heat the inner pot from the bottom,
It has a main body heating means for heating the inner pan from the side, and a lid heating means provided on the lid for heating the lid, and a control unit for controlling power supply to the main body heating means and the lid heating means is provided, and the rice is cooked. Further, in a jar rice cooker that keeps rice at an appropriate temperature, a control unit controls power supply to a main body heating unit and adjusts an inner pot on a main body side to a predetermined adjustment temperature, and a main body temperature adjustment unit.
Lid temperature control means for controlling energization of the lid heating means to adjust the lid to another predetermined control temperature, a predetermined control temperature on the main body side, a change means for changing the predetermined control temperature on the lid side at a constant cycle, Fluctuations were given to the predetermined adjustment temperature.

[0008]

According to the structure of the present invention, the predetermined adjusting temperature of the lid is changed to be higher or lower at a constant cycle by the changing means. For this reason, the temperature of the lid is relatively higher or lower, or the difference is significantly higher or slightly higher than the temperature of the inner pan adjusted to a substantially constant predetermined temperature. As a result, the condensed water having a low temperature and condensed starts to evaporate, and the inside of the inner pot becomes in a high humidity state. Next, the moisture contained in the humid air begins to condense slowly on the newly cooled one. By reversing the temperature relationship at regular intervals every time shorter than the time when dew condensation shifts completely to the other side by the change means, intensive dew condensation on either the inner pot or the lid will be avoided, Water does not drip into the inner pan, and a large amount of dew water does not drip to the main body when the lid is opened. In addition, it is possible to keep the lid warm and minimize the dew condensation and the drying and stickiness of the rice, and the inside of the inner pot is kept at a high humidity by the evaporation of the dew condensation water, thereby preventing the drying of the rice.

[0009]

Embodiments of the present invention will be described below with reference to the drawings. FIG. 1 is a sectional view of a jar rice cooker to which one embodiment of the present invention is applied, FIG. 2 is an operation flowchart during a warming operation of the jar rice cooker, and FIG. 3 is an operation of the jar rice cooker and each part. FIG. 4 is a temperature characteristic diagram, and FIG. 4 is an operation flowchart during a warming operation of a jar rice cooker according to another embodiment of the present invention.

In FIG. 1, an inner container 2 serving as an inner wall of a container is mounted inside a cylindrical main body 1 having an upper opening and a bottom. A body heating means 3 composed of an electric heater is attached to the side surface of the inner container 2, and a rice cooker heating means 4 composed of an electric heater or an induction heating coil and a pan bottom temperature sensor 5 are attached to the bottom of the inner container 2. The inner pan 6 is detachably housed in the inner container 2, and the bottom surface of the inner pan 6 and the pan bottom temperature sensor 5 are in contact with each other and thermally coupled.

A lid 7 is attached to the main body 1 via a hinge 8 so as to be openable and closable.
And the upper opening of the inner pan 6. A lid heating means 9 composed of an electric heater and a lid temperature sensor 10 are attached to a surface of the lid 7 facing the inner pot 6.

Inside the main body 1, there is provided a control unit 11 to which the main body heating means 3, rice cooking heating means 4, pan bottom temperature sensor 5, lid heating means 9 and lid temperature sensor 10 are connected. Further, the controller 11 receives the temperature of the pan bottom temperature sensor 5 and controls the power supply to the main body heating means 3 and the rice cooking heating means 4 to adjust the temperature of the main body 1 side, that is, the temperature of the inner pan 6. The lid temperature control means 13 for controlling the energization of the lid heating means 9 in response to the temperature of the lid temperature sensor 10 to adjust the temperature of the lid side, and a change for changing the temperature controlled by the lid temperature control means 13 at a constant cycle. It has means 14.

Next, the operation of this embodiment having the above configuration will be described.

[0014] The user puts the washed rice and an appropriate amount of water into the inner pan 6, stores it in the inner container 2, and closes the lid 7. Next, when a rice cooking operation is performed, rice cooking is started via the control unit 11 and electricity is supplied to the rice cooking heating means 4 so that the inner pot 6 is heated. Eventually, the inside of the inner pot 6 boils and the rice absorbs water, and when the water runs out, the temperature at the bottom of the inner pot 6 starts to rise rapidly. When the pan bottom temperature sensor 5 detects this rapid rise in the pan bottom temperature, the control unit 11 stops the energization of the rice cooking and heating means 4 and ends the heating. The operation of the control section 11 automatically shifts to the rice drying operation. After about 15 minutes, the rice cooking (including the rice drying) is finished and the rice is cooked. The operation of the control unit 11 shifts to a warming operation thereafter.

Next, a description will be given with reference to FIGS. 2 and 3 after the transition to the heat retaining operation. When the temperature of the pan bottom temperature sensor 5 falls below the regulated temperature T1 (for example, 72 ° C.) by the action of the main body temperature adjusting means 12 of the control unit 11, the heat is supplied to the main body heating means 3 to heat the inner pan 6 from the side. At the same time, a small amount of electricity is also supplied to the rice cooking heating means 4 to heat the inner pan 6 from the bottom, and when the temperature of the pan bottom temperature sensor 5 becomes equal to or higher than the regulated temperature T1 due to the heating, the heating to the main body heating means 3 and the rice cooking heating means 4 is performed. The operation of stopping energization is repeated. Thereby, the inner pan 6 is maintained at a substantially constant temperature, for example, 74 ° C.

In parallel with the operation of the main body temperature adjusting means 12, the operation of the lid temperature adjusting means 13 of the control section 11 causes
When the temperature of the lid temperature sensor 10 drops below the regulated temperature FT1 (for example, 72 ° C.), the lid heating means 9 is energized to heat the lid 7, and when the temperature of the lid temperature sensor 10 becomes equal to or higher than the regulated temperature FT1, The operation of stopping power supply to the lid heating means 9 is repeated. This makes the lid 7
Is maintained at a substantially constant temperature, for example, 73 ° C. When the temperature of the inner pan 6 is 74 ° C. and the temperature of the lid 7 is 73 ° C., moisture evaporated from the rice is condensed on the lid 7 having a lower temperature.

In this embodiment, the changing means 1 of the control unit 11
According to 4, the control temperature is changed repeatedly at regular intervals, that is, once every 5 minutes. As a result, the temperature controlled by the lid temperature control means 13 for 5 minutes is changed from FT1 (72 ° C.) to TF2 (78 ° C.) having a higher temperature. As a result, the temperature of the lid 7 rises and is kept at, for example, 79 ° C. During this time, the temperature of the lid 7 becomes higher than the temperature of the inner pan 6 of 74 ° C., so that the water condensed on the lid 7 evaporates from the lid 7, so that the air inside the inner pan 6 becomes highly humid and the inner pan 6 Condensation starts to shift to the side.

After 5 minutes, the temperature adjusted by the lid temperature adjusting means 13 returns to FT1. Thereby, the temperature of the lid 7 becomes lower than the temperature of the inner pan 6 again, and the dew condensation water on the side of the inner pan 6
It evaporates inside and begins to condense on the lid 7. As described above, during the warming operation, FT1 is alternately repeated for 5 minutes and FT2 is alternately repeated for the next 5 minutes, and the operation in which the relationship between the temperatures of the lid 7 and the inner pan 6 is reversed is repeated.

As described above, the dew is not concentrated on either the lid 7 or the inner pot 6, and a large amount of dew is prevented from dripping and breaking the rice, so that the rice can be kept in a delicious state. . Further, there is no problem that a large amount of dew water flows when the lid 7 is opened. Further, since the inside of the inner pot 6 is kept at a high humidity by the condensation water evaporation, it is possible to prevent the rice from drying and keep the rice in a delicious state with little drying even when keeping the temperature for a long time.

Next, another embodiment of the present invention shown in FIG. 4 will be briefly described. Unlike the first embodiment, the temperature control unit of the control unit 11 operates only with the temperature of the pan bottom temperature sensor 5 without providing the lid temperature sensor 10, and the main body heating unit 3,
The power supply to the rice heating means 4 and the lid heating means 9 is adjusted to adjust the temperature.

For example, when the temperature of the pan bottom temperature sensor 5 becomes lower than the regulated temperature T1 (for example, 72 ° C.), electricity is supplied to the main body heating means 3 and a small amount of electricity is also supplied to the rice cooking heating means 4. At the same time, the lid heating means 9 is energized by controlling the energization amount to 70%. When the temperature of the pan bottom temperature sensor 5 becomes higher than T1, the power supply to each heating means is stopped. By this repetition, the inner pan 6 is maintained at approximately 74 ° C., and the lid 7 is maintained at approximately 72 ° C. by repeating 70% energization and OFF.

Here, the power supply to the lid heating means 9 when the temperature of the pan bottom temperature sensor 5 is lower than the regulation temperature T1 is reduced by 70% by the changing means 14 of the control unit 11 at regular intervals.
To 100%. As a result, lid 7 is 100%
The temperature is kept at approximately 78 ° C. by repeating the energization and the OFF. As described above, even in the case where the temperature control by the temperature of the lid 7 is not performed, the temperature of the lid 7 is changed by changing the energization rate to the lid heating means 9 in a constant cycle, and the temperature of the inner pan 6 and the temperature of the inner pan 6 are changed. Since the relationship between the heights is reversed, the same effect as that of the one embodiment can be obtained.

[0023]

As described above, according to the present invention, in a jar rice cooker for keeping rice at an appropriate temperature after cooking rice, the control unit controls the energization of the main body heating means to bring the inner pot on the main body side to a predetermined regulated temperature. Main body temperature adjusting means for adjusting, lid temperature adjusting means for controlling energization of the lid heating means to adjust the lid to another predetermined adjusting temperature, and changing means for changing the predetermined adjusting temperature on the lid side at a constant cycle, Since the predetermined temperature of the lid is fluctuated, it is possible to prevent dew condensation on the lid, drying of the rice due to excessive rise in the temperature of the lid, and decay or stickiness due to too low the temperature of the inner pot,
This has the effect of providing a jar rice cooker that can keep warm for a long time while maintaining its deliciousness.

[Brief description of the drawings]

FIG. 1 is a sectional view of a jar rice cooker showing one embodiment of the present invention.

FIG. 2 is an operation flowchart of the rice cooker during a warming operation.

FIG. 3 is a diagram showing the operation of the rice cooker and temperature characteristics of each part.

FIG. 4 is an operation flowchart during a warming operation of a jar rice cooker according to another embodiment of the present invention.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Main body 3 Main body heating means 6 Inner pan 7 Lid 9 Lid heating means 11 Control part 12 Main body temperature adjusting means 13 Lid temperature adjusting means 14 Changing means

Claims (1)

(57) [Claims] 1. A and the inner pot is accommodated in the main body, a lid for covering an upper opening of the body and the inner pot, pan in provided in the body
Rice heating means for heating rice from the bottom, and heating the inner pan from the side.
It has a main body heating means for heating and a lid heating means for heating the lid provided on the lid, and a control unit for controlling energization to the main body heating means and the lid heating means is provided. In a jar rice cooker that keeps heat, the controller (11) controls the power supply to the main body heating means (3) to adjust the inner pot (6) on the main body (1) side to a predetermined control temperature. 12), a lid temperature adjusting means (13) for controlling energization of the lid heating means (9) and adjusting the lid (7) to another predetermined adjusted temperature, and a predetermined cycle of the predetermined adjusted temperature on the lid (7) side. Jar rice cooker, characterized in that the jar rice cooker is provided with changing means (14) for changing the temperature of the rice cooker.