JP2002168460A - Cooking device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide such a constitution as to avoid the fall and dispersion of the powder from fumed silica having a hyperfine porous structure due to vibration and the like and the constitution in which heat stress is hard to apply to a heating element as an upper heater. SOLUTION: There is such a constitution as to cover a reflection part 17 with a heat-insulating sheet 21 between the reflection part 17 of fumed silica and a heating element 18 in an upper heater 16 arranged on the top of a heating chamber 12. By this constitution, the fall and dispersion of the powder from the reflection part 17 are prevented, and the atmospheric temperature of the heating element 18 can be decreased. Moreover, the life of the heating element 18 can be extended.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a cooking device such as an oven or a microwave oven, and more particularly to a heater for heating an object to be heated.

[0002]

2. Description of the Related Art FIG. 4 is a schematic sectional view showing the structure of a conventional cooking apparatus of this type. In FIG. 4, a door 2 is provided on a front surface of the heating chamber 1, and upper heaters 3 are arranged on upper and lower wall surfaces of the heating chamber 1. The upper heater 3 provided on the upper wall surface of the heating chamber 1 includes a metal part 4, a reflecting part 5, a heating element 6, and an insulator 7. The insulator 7 is a heat-resistant insulator. Insulation with the metal part 4 was ensured by adopting a configuration in which the reflection part 5 was wrapped by the insulator 7. The upper heater 3 is attached to the oven upper plate 9 so as to radiate the heat of the upper heater 3 to the object 8 to be heated in the heating chamber 1. A heat-resistant sheet 10 made of ceramic is provided between the upper heater 9 and the upper heater 9 at the portion where the upper heater 3 is attached, in order to prevent powder from falling off the reflector 5. The heat generated from the heating element 6 heats the heat-resistant sheet 10, is released from the heat-resistant sheet 10 as heat of secondary radiation to the heating chamber 1, and heats the heated object 8 placed on the turntable 11. It was like.

[0003]

However, in the above-described conventional heater configuration, heat radiated from the heating element 6 of the upper heater 3 heats the heat-resistant sheet 10. Next, the heating chamber 1 is heated by the secondary radiation from the heat-resistant sheet 10. Therefore, there is a problem that energy is wasted such as rising of the heating chamber 1 and a long cooking time due to poor heating efficiency. In addition, heat generated from the heating element is blocked by the heat-resistant sheet 10, and the temperature of the heating element 6 is increased by retaining the heat. Therefore, the heating element 6 is durable.
However, there is also a problem that thermal oxidation is caused by the influence of thermal stress and the heating element 6 is disconnected.

[0004] The present invention solves the above-mentioned conventional problems, and can prevent powder from falling from the reflecting portion 5 and heat the heat source radiated from the heat generator 6 directly to the heating chamber 1 to heat the heat generator 1. It is an object of the present invention to provide a heater configuration in which the ambient temperature is lowered.

[0005]

SUMMARY OF THE INVENTION In order to solve the above-mentioned conventional problems, a heater structure according to the present invention has a structure in which a heater is provided between the reflector and the heating element in order to prevent powder from falling off the reflector and to lower the ambient temperature. The heat-resistant sheet is fixed to the periphery of the reflection part, a metal cover part and a heat-resistant insulator. By this, it is possible to prevent powder falling off of the reflecting portion composed of fumed silica having an ultra-fine porous structure, and the heat source radiated from the heating element directly heats the heating chamber, thereby lowering the ambient temperature, Thermal stress of the heating element can be eliminated.

[0006]

DESCRIPTION OF THE PREFERRED EMBODIMENTS The invention according to claim 1 comprises a heating chamber for heating an object to be heated, and a heating element for heating the object to be heated, wherein the heating element radiates heat. A heating element,
A reflecting portion made of fumed silica having an ultrafine porous structure for reflecting the heat of the heating element, a metal cover for fixing the periphery of the reflecting portion, and a heat-resistant portion provided between the reflecting portion and the metal cover. And a heat-resistant sheet provided between the heating element and the heating section.

[0007] By providing a ceramic sheet between the reflecting portion and the heating element, it is possible to prevent the reflecting portion, which is made of fumed silica having an ultra-fine porous structure, from powdering, and to reduce the ambient temperature. Can be done.

[0008]

An embodiment of the present invention will be described below with reference to the drawings. In this embodiment, a case where a high-frequency heating device is used as the heating cooking device will be described.

FIG. 1 is a schematic sectional view showing a high-frequency heating apparatus according to one embodiment of the present invention, FIG. 2 is a plan view of an upper heater of the high-frequency heating apparatus, and FIG. It is sectional drawing.

1 to 3, a door 13 is provided on a front surface of a heating chamber 12. In the embodiment of the present invention, the example in which the heating element portion (heater) is disposed on the upper and lower two wall surfaces of the heating chamber is shown. is not. Further, the number of heaters is not necessarily two, but may be one depending on the device. A heater is arranged on the upper and lower two walls of the heating chamber 12, and a punching hole 15 is partially provided in an upper plate 14 of the oven of the heating chamber 12, and an upper heater (heating element portion) 16 is provided thereon. I have. The upper heater 16 is composed of a reflector 17, a heating element 18, an insulating mica 19 as a heat-resistant insulator, a metal cover 20, and a heat-resistant sheet 21.

The heat-resistant sheet 21 is made of a ceramic material. It is needless to say that the material of the heat-resistant sheet does not necessarily have to be a ceramic material as long as it has heat resistance.

A heat-resistant sheet 21 is formed between the reflector 17 and the heating element 18, and the heat-resistant sheet 21 is covered with the reflector 17 so that the end faces thereof are insulated with the insulating mica 19 and the metal cover 2.
Insert into 0 and fix. The reflection part 17 is a compression molded body of fumed silica.

The fumed silica has an extremely fine cell structure, and has a composition containing an impermeable agent such as a heat-resistant metal oxide which minimizes the transmission of infrared rays. In order to effectively scatter the infrared rays, the reflectivity of the infrared rays is 90% or more, which is the same level as that of a metal, and has high heat insulation properties and high reflectivity. Therefore, by attaching the heat-resistant sheet 21 to the reflecting portion 17, powder falling from the reflecting portion 17 is eliminated, and the heat source radiated from the heating element 18 can directly heat the heating chamber 12.

However, fumed silica has an extremely fine cell structure, and there are countless gaps between the fine particles bonded to each other. If moisture enters these gaps, the insulation resistance decreases. I do. Therefore, insulation is ensured by inserting an insulating mica 19 having excellent heat resistance and insulation deterioration properties between the metal cover portion 20 and the reflecting portion 17. Since the insulating mica 19 has a soft waist, it can change its shape flexibly like paper, and is easy to handle.

In this embodiment, an example in which insulating mica is used as a heat-resistant insulating material has been described. However, the present invention is not limited to this, and any material having heat resistance and insulating properties comparable to those of insulating mica is used. Of course, that material may be used.

The material of the heating element 18 has a width of 5.2.
A 5 mm ribbon-shaped Fe-Cr-Al material is used.
Then, as shown in FIG. 2, the heating element 18 in the form of a ribbon is formed into a corrugated shape, integrated with the reflecting portion 17 and housed in the metal cover portion 19. In this embodiment, the thickness of the heating element 18 is 50 μm.
m, and the power consumption is 100v750w. As shown in FIG. 3, the heating element 18 includes an exposed portion 18a protruding from the surface of the reflecting portion 17 and an embedded portion 18b, and is fixed to the reflecting portion 17 by the embedded portion 18b.

The punching holes 15 of the oven upper plate 14 are
It plays a role in suppressing radio wave leakage. The punching hole 15 can be replaced because the performance is secured even if it is replaced with a stainless mesh net. Furthermore, punching hole 1
5 and other materials other than those described above may be used as long as they can suppress radio wave leakage to the same extent as that of the stainless steel mesh net.

A lower heater (heating element) 23 is provided below the oven bottom plate 22. Lower heater 23
The basic configuration is the same as that of the upper heater 16. That is, the lower heater 23 is also composed of the same reflection part 24, heating element 25, insulating mica 26, metal cover part 27, and heat-resistant sheet 28 as the upper heater 16, and the heat-resistant sheet 28 between the reflection part 22 and the heating element 25. And the heat-resistant sheet 28 is
Then, the end faces are inserted into the insulating mica 26 and the metal cover 27 and fixed. An insulating mica 26 is inserted between the reflecting portion 24 and the metal cover portion 27, and is attached to the oven bottom plate 22 in a state where insulation is ensured.

The lower heater 23 also has a configuration in which a heating element 25 is partially exposed on the surface of the reflection section 24 and the other is buried, and has a width of 2.25 mm, a thickness of 50 μm, a ribbon-like waveform, and the same composition. The material is used. Power consumption is 100V
480W.

The heat generated by the lower heater 23 heats the oven bottom plate 22 and is transmitted to the object 30 on the turntable 29 in the heating chamber 11 by radiation and convection.

Next, the operation and operation will be described. The object 30 to be heated in the heating chamber 11 is cooked by the heat from the upper heater 16 and the lower heater 23. At this time, since the heating elements 18 and 25 are formed as ribbon-shaped thin plates and partially exposed from the reflection sections 17 and 24, heat radiation is good,
In 3 seconds, the heater becomes red hot and reaches a predetermined temperature of the heater.

The reflecting portions 17 and 24 are made of fumed silica having a thermal conductivity smaller than that of still air, a large infrared reflectance of 0.90 or more, and an excellent high radiation heat shielding property. Therefore, heat from the heater is not easily radiated to the outside. The heat-resistant sheets 21 and 28 are made of a ceramic material, and the ceramic has a characteristic of emitting infrared rays. Further, by making the color of the heat resistant sheets 21 and 28 white, heat is further radiated. As a result, the rise of the internal temperature is accelerated, and the applied energy can be used efficiently for cooking.

The thickness and width of the heater wire are not limited to the numerical values of the embodiment, but can be arbitrarily selected. The heater material can also be selected from materials having heat resistance and excellent workability and durability. Further, the shape is not limited to the waveform, but the waveform shape enables the heater to be firmly held by the fumed silica.

The electric waves generated during the heating of the heater are emitted to the heating chamber to heat the object 30 placed on the turntable 29. Since the reflecting portions 17 and 24 are made of fumed silica having an ultra-fine porous structure, the strength of the reflecting portions 17 and 24 is very low.
When the insulating mica 19 and 26 are inserted into the metal cover portions 20 and 27, the insulating mica 19 and 26 are brought into contact with the surfaces along the shapes of the reflecting portions 17 and 24, so that they can be reliably held. Therefore, when the high-frequency heating device is transported, when the door is opened and closed, and when the upper and lower heaters are assembled, the reflecting portions 17 and 24 can be easily mounted.
Is no longer broken, and the reflection parts 17, 24 and metal cover part 2
The insulation between 0 and 27 can be ensured.

Further, since the reflecting portions 17 and 24 are made of fumed silica having an ultra-fine porous structure, there is a possibility that the powder may fall and scatter due to vibration or the like, so that the reflecting portions 17 and 24 may be used.
The heat-resistant sheets 21 and 28 are covered with the heat-reflective sheets 21 and 28 to prevent the powder from falling and scattering, and at the same time, reduce the ambient temperature of the heating elements 18 and 25 to reduce the heat stress and reduce the durability. It extends the life.

In this embodiment, the case where the heating element is used in the high-frequency heating device has been described. However, the present invention is not limited to this, and may be used in an electric heating device. in this case,
Punching holes and nets are unnecessary to prevent radio wave leakage.

[0027]

As described above, according to the heating and cooking apparatus of the present invention, since the reflecting portion is covered with the ceramic sheet, falling and scattering of the powder can be prevented, and the ambient temperature of the heating element can be reduced.

[Brief description of the drawings]

FIG. 1 is a schematic sectional view of a high-frequency heating device according to one embodiment of the present invention.

FIG. 2 is a plan view of an upper heater of the high-frequency heating device.

FIG. 3 is a cross-sectional view of the upper heater of FIG.

FIG. 4 is a schematic sectional view showing the configuration of a conventional high-frequency heating device.

[Explanation of symbols]

 REFERENCE SIGNS LIST 12 heating chamber 16 upper heater (heating element part) 17 reflecting part 18 heating element 19 insulating mica (heat resistant insulating material) 20 metal cover part 21 heat resistant sheet 23 lower heater (heating element part) 24 reflecting part 25 heating element 26 insulation Mica (heat resistant insulation) 27 Metal cover 30 Heated object

Continued on the front page F term (reference) 3K086 AA05 AA06 BA02 FA06 FA08 3K090 AA06 AA07 AB02 BA01 BB01 EB03 EB04 EB10 EB16 EB19 3L086 AA02 AA12 AA13 BA08 BB04 BD01 DA01 DA16 DA26 3L087 AA01 CA13 DA13 AC13 DA13

Claims (1)

[Claims] 1. A heating chamber for heating an object to be heated, and a heating unit for heating the object to be heated, wherein the heating unit reflects a heating element for radiating heat and a heat for the heating element. A reflecting portion made of fumed silica having an ultra-fine porous structure, a metal cover portion for fixing the periphery of the reflecting portion, a heat-resistant insulator provided between the reflecting portion and the metal cover, A heating cooking device comprising a heat-resistant sheet provided between the body and the reflection section.