JPS5839126Y2 - rice cooker - Google Patents

Description

[Detailed explanation of the idea] The present invention relates to a rice cooker with an improved heating method.

Conventional electric rice cookers are known to have a heating type in which a pot is removably placed on top of a hot plate equipped with an electric heater, and the heat from the electric heater is directly transferred from the hot plate to the bottom of the pot to cook rice. It is being

However, when rice is cooked using this type of rice cooker, the top part becomes crumbly with little moisture, and the bottom part becomes sticky with a lot of moisture, which results in uneven cooking and a deterioration in overall taste. Ta.

In addition, rice cookers with this type of structure require strict dimensional accuracy to ensure that the hot plate and pot are in close contact with each other, resulting in high costs.If the contact surfaces between the two become deformed or corroded during use, heat transfer may This has the disadvantage that the cooking becomes uneven, resulting in even more uneven cooking.

Therefore, in order to solve the above-mentioned drawbacks, a rice cooker using radiant heat has been considered in which a space for heating is provided around the outer periphery of the pot and a heater is disposed at a distance from the bottom of the pot.

In this case, it is necessary to appropriately set the amount of hot air that rises around the outside of the pot to equalize the temperature in the heating space, and if this becomes uneven, the rice will cook unevenly and the outer case In the case of regular rice cookers without internal insulation, the upper edge of the outer case gets hot, and if you accidentally touch it while cooking rice, you could get burned.

The present invention has been made in view of the above circumstances, and includes a pot in which an arcuate section having a predetermined curvature in cross-section is formed at the boundary between the bottom part and the peripheral wall part in the outer case. The outer case includes a reflective plate formed in the shape of a bottomed container that approaches the arcuate portion as it goes upward, and whose upper inner circumference surrounds the lower end of the peripheral wall of the pot with a slight gap. By providing a heater spaced apart from the bottom of the pot at the inner bottom of the reflector, the peripheral wall of the pot is kept at a substantially uniform temperature, thereby preventing uneven cooking. To provide a rice cooker which can cook rice without any heat, suppresses the temperature rise at the upper end of an outer case to a low level, and prevents the risk of getting burned even when touched.

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

Reference numeral 1 denotes a cylindrical outer case with a bottom, and a container-shaped reflecting plate 3 formed by drawing aluminum, for example, is disposed inside this via support legs 2.

4 is a substantially annular sheathed heater disposed at the inner bottom of the reflector 3 at a predetermined distance from the reflector 3; 5 is a substantially cylindrical support portion provided approximately at the center of the reflector 4; A bottomed cylindrical protection tube 6 whose upper surface is closed is supported by the support portion 5 so as to be movable up and down, and is always urged upward by a compression coil spring 7.

8 is a pin 1 attached to a support leg 9 erected on the bottom of the outer case 1.
The lever is rotatably supported through the lever, and has a knob 11 protruding outside the outer case 1 attached to one end thereof, and a rod 12 extending into the protective tube 6 at the other end. Rotatably connected.

13 is a permanent magnet fixed to the upper end of the rod 12;
15 is a compression coil spring that constantly urges the rod 12 downward; 16 is a magnet that opens and closes in conjunction with the rotation of the lever 8; This is a microswitch that is activated to control whether the sheathed heater 40 is turned on or off.

Now, 17 is a cylindrical pot with a bottom, and this is the peripheral wall part 17 a
An arcuate portion 17C whose cross-sectional shape has a predetermined curvature (radius R) is formed at the boundary between the bottom surface portion 17b and the bottom portion 17b, and a flange portion 17d is formed at the upper end portion.

The pot 17 is supported on, for example, three supporting protrusions 18 protruding from the inner surface of the reflector 3, and is housed in the outer case 1. In this housed state, the flange portion 17d is spaced apart from the upper end of the outer case 1 by a predetermined length, and the bottom surface 17b
is separated from the sheathed heater 4 by a predetermined length.

On the other hand, the upper half of the peripheral wall 3a of the reflector 3 has an arcuate cross-sectional shape with a larger curvature (radius R2) than the arcuate portion 17C, and the upper end of the reflector 3 Peripheral wall part 1
7a, and is opposed to the lower end portion of the pan 17 with a slight gap X, so that the peripheral wall portion 3a of the reflecting plate 3 has a shape that gradually approaches the arcuate portion 17C of the pot 17 as it goes upward.

3b is an annular flange portion formed at the upper end of the peripheral wall portion 3a of the reflecting plate 3 so as to be oriented outward.

Reference numeral 19 denotes a handle 20 rotatably supported by the outer case 1.
21 is an inner lid that contacts the flange portion 17d of the pot 17 to close the iron pot 17;
It is a compression coil spring that biases in the direction.

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

When rice and water are placed in the pot 17 and the knob 11 is pressed down, the permanent magnet 13 is attracted to the magnetic shunt material 14, the microswitch 16 is closed, and the sheathed heater 4 is energized.

Then, the radiant heat from the sheathed heater 4 heats the bottom portion 17b of the pot 17 directly and via the reflection plate 3.

On the other hand, the hot air inside the reflector plate 3 flows through the gap X between the circumferential wall part 17a of the pot 17 and the upper end of the circumferential wall part 3a of the reflector plate 3 to the circumferential wall part of the pot 17, as shown by the arrow in the drawing, due to natural convection. 1
7a, the pot 17 is well heated also from the peripheral wall 17a, and the pot 17
The temperature inside the tank tends to reach a high temperature state first in the upper part, and the temperature rise in the lower part tends to be slower than that in the upper part.

This is the opposite of the conventional heating method in which the pot is placed directly on a hot plate, so the rice can be cooked evenly.

As described above, according to the present embodiment, an arcuate portion having a predetermined curvature in cross section is provided at the boundary between the bottom surface portion and the peripheral wall portion of the pot, and as the peripheral wall portion moves upward, the arcuate portion Since the reflector plates are formed in the shape of containers with bottoms that are adjacent to each other in sequence, and the upper end surrounds the lower end of the peripheral wall of the pot with a slight gap, the amount of hot air rising through the gap can be appropriately controlled. At the same time, the hot air that has passed through the gap does not diffuse and rises along the circumferential wall of the pot, heating the circumferential wall of the pot uniformly so that the temperature difference between the top and bottom is as small as possible. This allows you to cook rice evenly.

According to the embodiment of the present invention, since the pot 17 is placed on the convex portion 18 provided on the reflector 3, the peripheral wall portion 17 of the pot 17
It is easy to set the gap X formed between the lower end of a and the upper end of the peripheral wall 3a of the reflector 3 to be uniform over the entire circumference, and the flange of the pot 17 Since the portion 17d is spaced apart from the upper end of the outer case 1, the heat from the pot 17, which becomes high during cooking, is not directly transmitted to the outer case 1, so that the coating on the outer case 1 is not peeled off due to the heat. Although this can be reliably prevented, the convex portion 18 may be provided as necessary, and the flange portion 17d of the pot 17 may be configured to be engaged with and supported by the upper end portion of the outer case 1.

As is clear from the above description, the present invention has a structure in which the inner periphery of the upper end of the reflector surrounds the lower end of the peripheral wall of the pot with a slight gap between the reflector and the pot. The gap can be set well, and the hot air that rises through this gap rises along the circumferential wall of the pot and heats the circumferential wall of the iron pot well, so the temperature difference between the upper and lower portions of the circumferential wall of the pot is reduced. It is made as small as possible, and the rice in the pot is heated evenly from the peripheral wall of the pot, allowing for even cooking.In addition, the hot air rises along the circumferential wall of the pot, and heat is transferred to the pot well. Therefore, even in a normal rice cooker that does not have an insulating material inside the outer case (does not have a heat retention function), the temperature rise at the top of the outer case can be kept low, and even if you touch the outer case while cooking rice, it will not heat up. It is possible to provide a rice cooker with excellent safety without the risk of getting burned.

[Brief explanation of drawings]

The drawings show an embodiment of the present invention, and FIG. 1 is a longitudinal sectional side view, and FIG. 2 is an enlarged perspective view of a single reflecting plate. In the drawing, 1 is an outer case, 3 is a reflective plate, 3a is a peripheral wall part, 4
17 is a sheathed heater, 17 is a pot, 17a is a peripheral wall portion, 17b is a bottom portion, and 17C is an arcuate portion.

Claims (1)

[Scope of utility model registration request] 1. A pan disposed within an outer case and having an arc-shaped section having a predetermined curvature in cross section at the boundary between a bottom surface portion and a peripheral wall portion; and a pot disposed within the outer case in the shape of a bottomed container and the peripheral wall a reflector plate which approaches the arc-shaped part of the pot as the part goes upward and whose upper inner peripheral part surrounds the lower end part of the peripheral wall part of the pot with a slight gap; A rice cooker comprising: a heater disposed at the bottom so as to be spaced apart from the bottom of the pot. 2. The rice cooker according to claim 1, wherein the reflective plate has a plurality of recesses for placing and supporting the pot.