JPS63267309A - Rice cooker - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

DETAILED DESCRIPTION OF THE INVENTION Field of Industrial Application The present invention relates to a rice cooker used in general households.

Conventional technology Cooking from the past! Two types of tV electric heaters are mainly used: (1) Fully cast heater, which is a sheathed heater made of aluminum, and (2) Sheathed heater C (for high temperature use). When using the cast aluminum heater (■), a direct heating method is used where the pot and electric heater come into direct contact, and when using a sheathed heater (■), the A1FF contact heating method is used where the pot and electric heater do not come into contact. The reality is that the positions of the pot and electric heater are changed depending on the electric heater being used.

However, in the direct heating method using a cast-in aluminum heater, the pot is in contact with electricity or overnight, so although it has excellent thermal efficiency, the heat transfer from the electric heater to the pot is mainly due to conduction. As a result, there is an imbalance in heat transfer depending on the degree of contact between the pot and the electric heater, or depending on the temperature sensor installed in the center of the electric heater or the top of the pot, which can cause uneven cooking of rice. In addition, the Wl electric heater pot requires strict dimensional accuracy so that it fits tightly, resulting in high costs and problems such as deformation or corrosion during use. There is a problem in that if further imbalance occurs, the uneven cooking phenomenon becomes even more noticeable.

On the other hand, in the indirect heating method using a high-temperature type sheathed heater (#), heat transfer from the electric heater to the pot occurs through thermal radiation, so the area near the electric heater is soft and the N9C heater There was a problem in that the farthest part (the center of the pot) was hard and unevenly cooked, resulting in poor taste.

To improve this, if the sheathed heater is made into a spiral shape,
The cost is high as it requires modification to improve the flatness of the heater and the need for fixing metal fittings. Also, since the heating area of the heater is small, the temperature of the heater itself is high, and there is no need to shield the rice cooker itself. Mizo-zukuri also has the disadvantage of requiring large-scale construction.

Therefore, in order to solve these problems, the present inventor has developed a top plate 80 with a reverse circular shape and a spiral top plate 80 made of a metal plate with a hole 80a in the center, as shown in FIG. The electric heating wire 81 is wound around the electric heating wire 8t and the groove 8 in which the electric heating wire 81 is arranged in a spiral shape.
2a and a hole 32b in the center, and is made of a heat insulating material mainly composed of silica-alumina fibers.
This heat insulating base 82 is housed, and a hole 83 is formed in the center.
A cylindrical storage case 83 is provided with a bottom having a diameter of 1.5 mm, and a fixing ring 34 is inserted into a hole 80a + 88a provided at the center of each of the top plate 80 and the storage case 88 to fix the top plate 80 and the storage case 88. We are proposing an electric heater with multiple configurations.

Furthermore, a rice cooker using the electric heater described above is also proposed in which the pot and the electric heater are located apart from each other with a certain heating space. This rice cooker is structurally similar to the conventional indirect heating method using a sheathed heater, but whereas the conventional rice cooker uses line heating, it uses surface heating, which heats the pot more evenly. Can be done. Therefore, the heat transfer from the W1 heater was in an ideal state, and the uneven cooking, which had been a problem in the past, was significantly improved, and the taste of the rice was also improved, resulting in a significant effect on rice cooking performance. Additionally, by using a material with high elastic conductivity, such as aluminum, for the protective frame, the taste of the cooked rice in the upper layer could be improved.

Problems to be Solved by the Invention However, the above-mentioned rice cookers that use electric heaters have the problem that the temperature at the top of the rice cooker body becomes high, and the protective frame is made of aluminized steel plate. By using materials with poor heat transfer coefficients, the temperature at the top of the rice cooker will be lower, but the taste of the upper layer of the rice will be lower.

There was a problem in that the taste of the upper layer of cooked rice had to be improved by placing a heater in close contact with the side surface of the protection frame and raising the temperature of the upper part of the protection frame.

The present invention solves the above problems, improves rice cooking performance,
An object of the present invention is to provide a rice cooker which is excellent in suppressing abnormal temperature rise at the upper part of the rice cooker main body.

Means for Solving the Problems In order to solve the above problems, the rice cooker of the present invention includes a top plate made of a metal plate, a spirally wound heating wire, and a spirally arranged heating wire. An electric heater consisting of a heat insulating base made of an LFR heat material having grooves and mainly composed of silica-alumina fibers, and a storage case made of a metal plate that houses the heat insulating base, and housing food to be cooked. The method includes a pot and a protective frame for storing the pot, a heating space is provided between the protection frame and the pot, and the electric heater is installed within the heating space at a predetermined distance from the pot. At the same time, the protective frame is divided into upper and lower parts, the lower protective frame is made of a metal with high thermal conductivity, and the upper protective frame is made of a metal with lower thermal conductivity than the metal of the lower protective frame. It is.

Function In the above configuration, the electric heater used has a considerably wider heat generating area than the conventional indirect heating method using a sheathed heater, which enables uniform heating of the pot and reduces uneven cooking. This will eliminate the outbreak and improve the taste of the rice.

Furthermore, the protective frame is divided into upper and lower parts, and the lower protective frame is made of a metal with high thermal conductivity such as aluminum, and the upper protective frame is made of a metal with high thermal conductivity such as aluminized steel plate. By using low-temperature metal, it is possible to prevent the temperature rise in the upper part of the rice cooker body and improve the rice cooking performance at the same time.

This is because the upper protective frame is made of a material with high thermal conductivity such as aluminum, so the heat from the Wt electric heater is transmitted to the side of the pot (through the protective frame), heating the pot from the side and heating the pot from the side. This is because by using a material with low thermal conductivity, such as an aluminized steel plate, for the protective frame, the rise in temperature of the lower protective frame can be suppressed. It is preferable to connect the protective frame between 50 and 80 fins from the bottom of the pot in order to ensure the same level of rice cooking performance as when the protective frame is made of aluminum and to suppress the rise in temperature at the top of the protective frame.

Example Embodiments of the present invention will be described below with reference to the drawings.

Figure @i is a partially cutaway side view of a rice cooker according to an embodiment of the present invention. In this figure, the rice cooker body has an almost cylindrical shape with a bottom plate, and the upper part is open. A protective frame 8 having a shaped bottom is provided. The protection frame 3 is formed by joining a lower protection frame 3a made of aluminum and an upper protection frame 8b made of aluminized steel plate, using different materials for the upper and lower parts. An annular upper frame 4 made of heat-resistant plastic is fitted onto the inner peripheral surface of the upper end of the rice cooker main body mouth, and a protective frame 8 is attached to the upper frame 4.
The outer peripheral surface of the upper end is fitted.

A pot 5 is removably housed inside the protective frame 3. The pot 5 has a flange 6 formed outward at the edge of the upper opening, and this flange 6 is attached to the upper surface of the upper frame 4.
By doing so, it is stably housed inside the protective frame 8. The upper and lower parts of the protective frame 3 are joined at a position corresponding to about 80 mm above the bottom of the round bar 5.

An electric heater 7 is installed below the pot 5 in a heating space 8 formed between the bottom of the protective frame 3 and the bottom of the pot 5, and is provided at a predetermined distance from the bottom of the pot 5. 8a apart. As shown in FIG. 2, the W1, gC heater 7 includes a top plate 7a made of stainless steel 5US304,
It is composed of a heat insulating base 7b formed using a heat insulating material whose main component is relicar alumina fiber, an electric heater @7c, and a storage case 7d made of stainless steel SUS 480 qB that houses the heat insulating base 7b. The top plate 7a has a lid shape and has six claws 7e bent inward on the side edges, a hole in the center, and a convex R20 groove on the whole.
It has 00 spherical stamping and is coated with heat-resistant paint.

The tlfrP substrate 7b is provided with a spiral groove 7f and a hole in the center, and the heating wire 7C is disposed inside along the spiral shape of the groove 7f. The storage case 7
d has a hole in the center and six square holes 7g in the side edges, with which the claws 7e are engaged when fitting with the top plate 7a. . The electric heater 7 is assembled as described in 1! The heat insulating base 7b with the hot wire 7C arranged in the groove 7f is stored in the storage case 7d, and the top plate 7 is inserted from above.
a, lock the claw portion 7e in the square hole 7g, and insert the fixing ring 7h through the hole in the center to integrate the heater 7 with the protective frame 8. It is supported by a support member (not shown) and attached to the bottom of the holder.

A heat-sensitive element 9 for detecting the end temperature of rice cooking is disposed in the center of the heating space 8 and is attached to the protection frame 3.

Further, a micro switch is provided between the bottom of the rice cooker main body 1 and the bottom of the protective frame a, and is turned on and off by a lever electric 0 that is linked to a heat-sensitive element 9 to control the energization of the r11 air heater 7. ■ is provided. Further, a display plate I2 is attached to the side surface of the rice cooker main body 1, and a button 18 is attached to the lever 10. Further, a lid t4 is attached to the opening of the rice cooker main body l so as to be openable and closable.

The operation of the above rice cooker will be explained. First, washed rice and water are placed in the pot 5, the pot 5 is housed inside the protective frame 8, and the lid 14 is closed. By pressing the button 13, the lever IO rotates, the heat-sensitive element 9 linked to the lever 10 operates, and the rice cooking mode is activated.
When υ is input, the electric heater 7 is energized. When the electric heater 7 generates heat, the air inside the sealed heating space 8 is heated, and the pot 5 is heated through this heated air. The rice is cooked by heating the pot 5, and when all the water in the pot 5 is absorbed by the rice, the pot 5
The bottom of the oven becomes dry and the temperature rises rapidly. At this time, the temperature of the heat-sensitive element 9 also rises, the lever IO is pushed down, the microswitch 1t is opened, and the [fi heater 7
The electricity stops flowing to the rice cooker and cooking is completed.

In the above-mentioned rice cooker, the heat generating area of the electric heater 7 is made into a larger area than when using a conventional sheathed heater, so that the pot 5 can be heated uniformly, and the lower protective frame 8a is heat conductive. Since it is made of high-density aluminum, it can be heated from the side of the pot 5, and there is no uneven cooking, and the taste of the rice is extremely good, including the upper layer of the cooked rice.In addition, the upper protective frame 8b Since the rice cooker is made of an aluminized steel plate with low thermal conductivity, an abnormal temperature rise does not occur in the upper protective frame 3b and the upper part of the rice cooker main body 1.

In addition, in order to evaluate the temperature of the protective frame 3 in the rice cooker of the above example, rice was cooked using the protective frame 3 formed using aluminum and aluminized steel plate, respectively, and the protective frame of this example. , the temperature at the top of the protective frame was measured. The results are shown in Table 1. As shown in Table 1, in this embodiment, the protective frame 8 is divided into upper and lower halves, the lower protective frame 8a is made of a metal with high thermal conductivity such as aluminum, and the protective frame 3b is made of aluminum. By using a metal having a lower thermal conductivity than the metal of the lower protective frame 3a, such as a plated steel plate, the rice cooking performance was not deteriorated and the heat shielding effect was excellent.

Table 1 Effects of the Invention As described above, the rice cooker of the present invention has a top plate made of a metal plate, a spirally wound main heating wire, and a groove in which the heating wire is arranged in a spiral manner, and A heating space formed between the protective frame and the pot is equipped with an electric heater consisting of a heat insulating base made of a heat insulating material mainly composed of silica-alumina fibers and a storage case made of a metal plate that houses the heat insulating base. The protective frame is divided into two parts, upper and lower, the lower protective frame is made of a metal with high thermal conductivity such as aluminum, and the upper protective frame is Since it uses a metal with lower thermal conductivity than the metal of the lower protective frame, such as aluminum sheet metal plate, the heating area is wide and planar, compared to the conventional indirect heating method using a sheathed heater. The pot can be heated evenly, and the high thermal conductivity of the metal sheath on the lower protective frame means that the heat is also applied from the sides of the pot, preventing uneven cooking and allowing the rice to cook evenly. The taste of the rice is very good, including the layers, and the low conductivity of the metal in the upper protective frame prevents abnormal temperature rises in the lower protective frame and the top of the rice cooker.
It is safe, there are no accidents such as burning, and the rice cooking performance is good.
Moreover, it exhibits an excellent heat shielding effect.

[Brief explanation of the drawing]

Fig. 1 is a partially cutaway side view showing a rice cooker according to an embodiment of the present invention, Fig. 2 is a sectional view of an electric heater of the same rice cooker, and Fig. 3 is an exploded perspective view of a conventional electric heater. be. 2... Insulating material, 3... Protective frame, 3a... Lower protective frame, 3b... Upper protective frame, 5... Pot, 7... Z'
X heater, 7a...top plate, 7b...insulation base, 7C
...Heating wire, 7d...Storage case, 7f-...Groove,
8... Heating 940 parts.

Claims (1)

[Claims] 1. A top plate made of a metal plate, a spirally wound heating wire,
It has a groove in which the heating wire is arranged in a spiral shape, and
An electric heater consisting of a heat insulating base made of a heat insulating material mainly composed of alumina fibers, a storage case made of a metal plate that houses the heat insulating base, a pot that houses the food to be cooked, and a protection housing that houses the pot. A heating space is provided between the protective frame and the pot, the electric heater is installed in the heating space at a predetermined distance from the pot, and the protective frame is placed vertically. A rice cooker that is divided into two parts, the lower protective frame is made of metal with high thermal conductivity, and the upper protective frame is made of metal with lower thermal conductivity than the metal of the lower protective frame.