JPS5856579Y2 - electric rice cooker - Google Patents

Description

[Detailed explanation of the idea] This invention relates to the improvement of electric rice cookers.

Among conventionally used electric rice cookers, a so-called double pot type rice cooker is a rice cooker in which a heating element equipped with a heater is installed inside the outer casing, and the inner pot is placed directly on top of this heating element. There is.

This double pot rice cooker heats the inner pot directly with a heating element, so it is efficient, but since the heating time is small, the inner pot is made thicker to improve thermal efficiency. It is normal for there to be.

However, if the inner pot is made thicker, it becomes heavier, which makes it inconvenient to handle and increases the cost.Also, even if the inner pot is made thicker, the heating condition tends to be uneven. .

On the other hand, there is a so-called triple pot type rice cooker in which a heating pot equipped with a heater is provided inside the exterior body, and an inner pot is housed in the heating pot so that it can be taken in and out.

This triple pot rice cooker usually cooks rice with a certain amount of water placed between the heating pot and the inner pot.

As described above, triple pot rice cookers use water as a medium to heat the inner pot, so while they have the advantage of having a large heat capacity and being able to achieve uniform heating conditions, they have the disadvantage of low efficiency.

This idea was made in view of the above points, and the structure was
To provide an electric rice cooker which is of a heavy pot type, does not require water as a heat medium, has good thermal efficiency, and can uniformize the heating state.

An embodiment of this invention will be described below with reference to the drawings.

In FIG. 1, 1 is an exterior body, and inside this exterior body 1, a heating pot 2 made of aluminum or aluminum alloy, such as aluminum casting, is fixed.

A large-capacity rice-cooking main heater 3 is installed in the bottom of the heating pot 2 in a ring-shaped manner.

Further, on the outer surface of the side wall of the heating pot 2, a relatively small-capacity sub-heater 4 for rice cooking used as a sub-heater of the main heater 3, and a relatively small-capacity heat-retaining heater 5 used for keeping warm are provided on the side wall, respectively. It is attached so that it goes around the outer circumference.

Furthermore, a thermal switch 6 for heat retention is attached to the outer surface of the side wall of the heating pot 2.

The thermal switch 6 is in an on state when the temperature of the heating pot 2 is below a predetermined temperature, and is in an off state when the temperature of the heating pot 2 is above a predetermined temperature.

Further, a notch hole 7 is provided in the bottom surface of the heating pot 2, and a thermal switch 8 for rice cooking is provided in this notch hole 7.

Inside the heating pot 2, an inner pot 9 containing rice and an amount of water determined according to the amount of rice is stored in a manner that can be taken out and put in freely. It can be installed freely.

A heater 11 with a very small capacity is attached to the outer surface of the inner lid 10 in the central part thereof.

This heater 11 is provided to prevent water droplets from adhering to the inner surface of the inner lid 10 during the rice cooking operation.

Furthermore, an inner cover 9. An outer lid 12 is detachably attached to cover the heating pot 2.

Thus, the heating pot 2 has a bottom wall portion that contacts the outer surface of the bottom wall of the inner pot 9 and supports the inner pot 9, and a space that covers the outer surface of the side wall of the inner pot 9 and the outer surface of the side wall. and a side wall portion formed at an inner diameter in which a minute gap exists that does not obstruct the insertion and removal of the inner pot 9.

In addition, 13 in the figure is a rice cooking start switch lever, and rice cooking is started by pushing down this lever 13.

When the lever 13 is pressed down, the rice cooking thermal switch 8 is pushed up and brought into contact with the bottom of the inner pot 9.

This thermal switch 8 detects the temperature of the inner pot 9,
When the inner pot 9 rises to a predetermined temperature, the inner pot 9 instantly
This causes the rice cooking start switch lever 13 to return to its original position.

Fig. 2 shows a schematic electrical circuit of the electric rice cooker according to this invention, in which the main heater 3 and sub-heater 4 for rice cooking are connected in parallel, and the A series circuit is formed with the thermal switch 8.

A heater 11 attached to the inner lid 10 is connected in parallel to the thermal switch 8, and a heat-retaining heater 5 and a heat-retaining thermal switch 6 connected in series to the heater 5 are connected in parallel. It is connected.

Next, the operation of this device configured as described above will be explained.

First, when the rice cooking start switch lever 13 is pushed down, the rice cooking thermal switch 8 is turned on.

As a result, current flows through the main heater 3 and the sub-heater 4), and each of these heaters generates heat to start the rice cooking operation.

Then, after a predetermined period of time, when the temperature of the inner pot 9 rises rapidly and reaches the set temperature, the thermal switch 8 is turned off.

After the thermal switch 8 is turned off and a predetermined time has elapsed, the heat-retaining heater 5 is operated by turning on and off the heat-retaining thermal switch 6 to perform a heat-retaining operation.

In addition, during this warming operation, the main heater 3 for cooking rice
．． The sub-heater 4 generates a very small amount of heat.

An experimental example of temporal changes in the temperature of the inner pot 9 and the rice in the inner pot 9 during the above operation is shown by curve 19 in FIG.

The curve A shows the temperature change in the inner pot 9, and the curve opening shows the temperature change in the rice.

In addition, in FIG. 3, curve C. Figure 2 shows the temperature changes in the inner pot and rice using the conventional method.

According to this Figure 3, it can be seen that the gelatinization time T1 of rice according to the present invention can be approximately 2 to 3 times longer than the conventional gelatinization time T2, and even better rice cooking can be achieved. .

The reason why the device of the present invention can cook rice well is that the heating pot 2 is made of aluminum or an alloy thereof, and the side wall of the heating pot 2 is brought as close as possible to the outer surface of the side wall of the inner pot 9. Additionally, a sub-heater 4 is provided on the side wall of the heating pot 2.

This makes it possible to improve thermal conductivity, improve thermal efficiency, and make the heating state uniform.

That is, when cooking rice, two heaters, the main heater 3 and the sub-heater 4, generate heat at the same time, and the entire surface of the inner pot 9 is heated via the heating pot 2, which is made of cast aluminum or the like, so that rice can be cooked evenly in a short time. Since the heating pot 2 is made of cast aluminum or the like, the steaming effect after cooking the rice is great, and the inner pot 9 does not need to be thin.

As explained above, according to this invention, the structure is a triple pot type, and by eliminating the need for water as a heat medium, it is possible to improve thermal efficiency, and by creating a structure that can heat the entire surface of the inner pot. It is possible to provide an electric rice cooker that can uniformize the heating state and cook rice uniformly and well in a short time.

[Brief explanation of the drawing]

FIG. 1 is a sectional view showing the configuration of an electric rice cooker according to an embodiment of this invention, and FIG. 2 is a schematic electric circuit diagram of the same embodiment.
FIG. 3 is a diagram showing the operation of the same embodiment in comparison with the conventional one. 1...Exterior body, 2...Heating pot, 3...
... Main heater for rice cooking, 4 ... Sub heater for rice cooking, 5 ... Heater for keeping warm, 9 ....
・Inner pot.

Claims (1)

[Scope of utility model registration request] An inner pot for cooking rice, a heating pot that houses the inner pot inside,
In this electric rice cooker comprising a heater attached to the heating pot, the heating pot is integrally formed of aluminum or an aluminum alloy, and a bottom wall portion supporting the inner pot; a side wall portion that covers the entire outer surface of the side wall of the inner pot and is formed in an inner diameter such that a minute gap exists between the outer surface of the side wall and the inner pot so as not to obstruct the insertion and removal of the inner pot; An electric rice cooker comprising a main heater attached to a bottom wall of the pot and a sub-heater attached to a side wall of the heating pot.