JPH0740988B2 - rice cooker - Google Patents

Description

TECHNICAL FIELD The present invention relates to a rice cooker used in general households,
In particular, it relates to a rice cooker with improved cooking performance with an electric heater.

2. Description of the Related Art Conventionally, as electric heaters for rice cookers, two main types are used: (1) an aluminum cast heater in which a sheath heater is embedded in an aluminum cast (2) a sheath heater (high temperature type). When using the aluminum cast heater of (3), the direct heating method that directly contacts the pan and the electric heater is adopted, and when using the sheath heater of (2), the indirect heating method that does not contact the pan and the electric heater is adopted. In reality, the positions of the pan and the electric heater are changed according to the type of electric heater used.

However, in the direct heating method using the aluminum casting heater of (1), since the pot and the electric heater are in contact with each other, the thermal efficiency is excellent, but the heat from the electric heater to the pot is high. Since heat transfer occurs due to heat conduction, imbalance occurs in heat transfer depending on the degree of contact between the pan and the electric heater, and depending on the location such as the temperature sensor part provided in the central part of the electric heater and the top of the pan. The uneven phenomenon is likely to occur, and as a result, there is a problem that the taste is deteriorated as a whole.

Also, in order to make the electric heater and the pot adhere closely,
Since strict dimensional accuracy is required, there is a problem that the cost becomes high, and if the heat transfer is further unbalanced due to deformation or corrosion during use, the uneven cooking phenomenon is further aggravated.

On the other hand, in the indirect heating method that uses the high-temperature type sheath heater of (2), heat transfer from the electric heater to the pan occurs due to heat radiation, so stickiness occurs in the portion close to the electric heater and the electric heater is used. There was a problem that the unevenness in cooking, such as firmness, occurred in the more distant part (upper part of the pot), and the eating quality deteriorated.

In order to improve this, if the sheathed heater is formed into a spiral shape, the cost is increased because the flatness of the heater is corrected and fixing metal fittings are required.

Further, since the heater has a small heat generation area, the temperature of the heater itself becomes high, and as a result, the heat shield structure of the main body also becomes large.

The present invention has been made to solve the above problems, and an object of the present invention is to provide a rice cooker capable of ideal rice cooking with less uneven cooking.

Means for Solving the Problems In order to solve the above problems, the present invention has a spirally wound heating wire, a groove for spirally arranging the heating wire, and a silica-alumina fiber as a main component. An electric heater composed of a heat insulating base made of a heat insulating material and a storage case for storing this heat insulating base, and the outer peripheral surface is subjected to black treatment,
And a pot for storing the cooked rice, and a protective frame made of a stainless steel-aluminum clad material for accommodating the pot and having black treatment on the inside, and the electric heater on the outside of the protective frame. It is attached, and a heating space is formed around the pot by the protection frame.

Action Since the rice cooker of the present invention has the electric heater attached to the outside of the protective frame, the heat of the electric heater is easily transferred to the protective frame, and the entire protective frame acts like one heating source. This makes it structurally similar to the indirect heating method that uses a conventional sheathed heater, but the conventional method is line heating, whereas surface heating is more uniform. Can be heated.

Further, in the present invention, since the stainless steel-aluminum clad material is used as the material of the protective frame, the heat of the electric heater is more uniformly transferred to the protective frame.

For this reason, the rice cooker of the present invention has a structure closer to that of an old oven, and as a result, the heat around the electric heater is in an ideal state, which is not so good as the taste of rice and is more problematic than before. The unevenness of cooking, which was said to be the case, is also significantly improved, and a significant effect on rice cooking performance can be obtained.

Further, since there is no portion where the electric heater and the pot contact each other, strict dimensional accuracy is not required, and the cost can be obtained at low cost.

On the other hand, regarding the thermal efficiency, since the protective frame and the pan are subjected to a black treatment that is excellent in absorbing and radiating heat, the heat from the electric heater is efficiently transferred to the rice to be cooked.

By the way, the above-mentioned stainless-aluminum clad material is molded so that aluminum is located on the electric heater side and stainless steel is located on the pan side, and is used as a protective frame.

As described above, by using the stainless-aluminum clad material as the protective frame, the heat resistance and corrosion resistance of stainless steel can be utilized in addition to the uniform heat distribution of the electric heater described above. The power consumption can be further increased, and the appearance is not spoiled even under a corrosive environment such as salt.

Since the electric heater uses a heat insulating material containing silica-alumina fiber as a main component as a heat insulating base, the heat from the heating wire is efficiently transmitted to the protective frame, and the movement to the lower surface is suppressed. . Therefore, the thermal efficiency does not significantly decrease as compared with the conventional indirect heating method using the sheathed heater.

As is clear from the above description, in the rice cooker of the present invention,
It does not require strict dimensional accuracy and can be manufactured at low cost, making it possible to cook ideal rice with less unevenness in cooking.

Example Hereinafter, a specific example of the present invention will be described with reference to FIGS. 1 and 2.

In the figure, reference numeral 1 is a substantially bottomed cylindrical rice cooker body with an open top surface. Inside the rice cooker body 1, a substantially bottomed cylindrical protective frame 3 as a pot storage portion is provided via a heat insulating material 2. It is arranged. The protective frame 3 is made of a stainless-aluminum clad material, and the outer periphery of the upper end of the protective frame 3 is a ring-shaped upper frame 4 made of heat-resistant plastic fitted around the inner periphery of the upper end of the rice cooker body 1. Is fitted to. The protective frame 3 is formed so that stainless steel is located on the pan side.

Reference numeral 5 denotes a pan having an outwardly projecting flange 6 formed at the edge of the upper opening, and the pan 5 is arranged in the protective frame 3 by placing the flange 6 on the upper surface of the upper frame 4. Also, pan 5
The outer peripheral surface of is subjected to black treatment with black alumite using an inorganic heat resistant dye.

Reference numeral 7 is an electric heater, and the electric heater 7 is composed of the following members. 7a is a heat insulating base made of a heat insulating material containing silica-alumina fiber as a main component, and this heat insulating base 7a is provided with a spiral groove 7b and a hole at the center.
7e is provided. The heating wire 7c is spirally wound, and the heating wire 7c is arranged in the groove 7b provided in the heat insulating base 7a.
7d is a storage case for storing the heat insulating base 7a in which the heating wire 7c is arranged.The storage case 7d is made of SUS430, and has a hole 7f at the center, and further has a convex shape on the inner peripheral surface and the outer peripheral surface. Shaped ribs 7g, 7h are provided.

The electric heater 7 having the contents described above is attached and integrated to the outside of the protective frame 3 by using the storage case 7d of the electric heater 7.

A heating space 8 is provided between the electric heater 7 and the pan 5.
Is formed. Further, a heat-sensitive element 9 for detecting the end-of-cooking temperature is attached to the protective frame 3, and this heat-sensitive element 9 is linked with a lever 10, which lever 10 has an electric heater 7.
The microswitch 11 for controlling the energization of is turned on and off.

Reference numeral 12 is a display board, and the display board 12 is attached to the rice cooker body 1. Reference numeral 13 is a button, which is attached to the lever 10. Reference numeral 14 is a lid, and the lid 14 is openably and closably attached to the upper opening of the rice cooker body 1.

Next, the operation of the rice cooker of the present invention having such a configuration will be described. First, the washed rice and water are stored in the pan 5, the pan 5 is stored in the protective frame 3, and the lid 14 is closed. Then, when the button 13 is pressed, the lever 10 is rotated, the thermosensitive element interlocked with the lever 10 is operated, and the rice is cooked. At the same time, the micro switch 11 is turned on and the electric heater 7 is energized.

When the electric heater 7 generates heat, the air in the closed heating space 8 is heated, and the pot 5 is heated via this heated air. Rice is cooked by heating the pot 5. When the water in the pan 5 is completely absorbed by the rice, the bottom of the pan 5 is in an empty state and the temperature rises rapidly. At this time, the temperature of the heat sensitive element 9 also rises and pushes down the lever 10. As a result, the micro switch 11 is turned off to stop the power supply to the electric heater 7, and the rice cooking is completed.

In this way, the rice cooker of the present invention cooks rice, but as described above, in the present invention, since the stainless steel-aluminum clad material is used as the material of the protective frame 3, the electric heater is used. The heat of 7 is more evenly transferred to the protective frame 3 to heat the pot 5, so that delicious rice without unevenness in cooking is completed.

EFFECTS OF THE INVENTION As is clear from the description of the above embodiments, according to the present invention, a heating wire spirally wound, a groove having spirally arranged heating wire, and silica-alumina fiber An electric heater consisting of a heat insulating base made of heat insulating material as the main component and a storage case for storing this heat insulating base, a pot with a black treatment on the outer peripheral surface and storing rice to be cooked, and this pot is stored And a protection frame made of a stainless steel-aluminum clad material that has been subjected to black treatment on the inside, the electric heater is attached to the outside of the protection frame, and a heating space around the pot is further provided by the protection frame. Since the parts are formed, it is possible to provide a rice cooker capable of ideal rice cooking with less uneven cooking.

[Brief description of drawings]

FIG. 1 is a cutaway side view of a rice cooker showing an embodiment of the present invention,
FIG. 2 is a sectional view of an electric heater in the rice cooker. 3 ... Protective frame, 5 ... Pan, 7 ... Electric heater, 7a ... Insulation base, 7b ... Groove, 7c ... Heating wire, 7d ... Storage case,
8: Heating space section.

Claims (1)

[Claims] 1. A heat-insulating base comprising a spirally wound heating wire, a groove for spirally arranging the heating wire, and a heat-insulating material containing silica-alumina fiber as a main component, and the heat-insulating base. An electric heater composed of a storage case for storing, a pan with an outer peripheral surface subjected to black treatment and for storing cooked food, and a stainless steel-aluminum housing this pan and having a black treatment inside A rice cooker having a protective frame made of a clad material, the electric heater attached to the outside of the protective frame, and a heating space portion formed around the pot by the protective frame.