JPS62186132A - Cooking unit - Google Patents

Abstract

PURPOSE:To provide a cooking unit having an oil decomposing function and a infrared ray radiation function by a method wherein a specified covering is formed on the surface of a metallic base material forming a cooking chamber of a cooking unit. CONSTITUTION:A covering film having an oil decomposing function and an infrared ray radiation function is formed on the surface of a metallic base material forming a cooking chamber of a cooking unit. The covering film is composed perovskite type oxide of composite oxide of rare earth elements and metallic elements, at least one or more kinds of oxides selected from a group of elements of Zr, Ti, Si, Al, at least one or more kinds of oxides selected from a group of elements of Fe, Co, Ni, Mn and Cu, and a hardened body of borosiloxane resin. This hardened body has a heat- resistant temperature of at least 1,000 deg.C or more, its adhesion with a metallic base material is superior and a temperature of inner surface of a cooking chamber can be increased. The peroviskite type complex oxide has an oxidation activity and decomposes hydrocarbon compound such as oil component or the like with oxidation, resulting in that a self-cleaning ability can be applied to the covering film. The covering film has a high radiation rate of infrared ray, a raadiation rate of about 0.8 with a wave length of 2-7mum and a radiation rate of about 0.9 or more with a wave length of 7-30mum.

Description

DETAILED DESCRIPTION OF THE INVENTION Field of the Invention The present invention relates to cooking appliances such as open cookers, grills, and the like that use electricity as a heat source for domestic or commercial use.

Conventional technology Conventional heating means for ovens and grills have been various depending on the heat source, such as a sheathed heater built into the cooking chamber or a radiant heated by a gas burner inside the cooking chamber. .

In the case of electricity, most of them incorporate sheathed heaters as mentioned above, and some use planar heaters.

On the other hand, in order to decompose the oil generated during cooking, we installed an S, C, film with self-purifying ability (hereinafter referred to as S, C0) inside the cooking chamber as a means to decompose the oil generated during cooking. There is.

Problems to be Solved by the Invention The problems with the prior art described above are that, in the case of a sheathed heater as a heating means, (1) the effective heating area of the heater itself is extremely small relative to the ceiling area of the cooking chamber, and the cooking speed is slow; Heat source cannot be used effectively.

In the case of a flat heater, (2) the effective heating area is almost equal to the ceiling area of the cooking chamber, so there is no problem;
Since the heat resistance of the coated surface is not very high, it becomes impossible to raise the temperature of the heater or the inside of the cooking chamber. Therefore, the effective heating area cannot be fully utilized. Another problem with the above configuration is that the infrared emissivity of the inner surface of the cooking chamber is not so high.

On the other hand, from the perspective of S, C0, C3) Since S, C, Noh is applied to the ceiling surface of the cooking chamber by enameling, the heat resistance temperature is approximately 400°.
In C, if the temperature of the ceiling surface exceeds this temperature, there is a concern that phenomena such as the glass component of the enamel melting or peeling from the base material may occur. The film thickness of enamel is as thick as several 100 μm, and from this point of view, it is easy to peel off due to thermal cycles, and as a matter of course, if it peels off, the S, C, and performance will decrease.

Means for Solving the Problems In order to solve the problems, the present invention provides a cooking device such as an oven or a grill using a plane heater, which includes a metal base material forming a cooking chamber of the cooking device; A coating having both oil-decomposing ability and infrared radiation ability is formed on the inner surface of the cooking chamber made of a metal base material, and the coating is made of perovskite-type oxide, which is a composite oxide of a rare earth element and a metal element, and Zr. , Ti, Si, at least one oxide selected from the element group 84, and Fe,
Co, Ni, Mn.

It is composed of at least one oxide selected from the Cu element group and a cured body of borosiloxane resin.

For production By means of the above means, the present invention has the following effects.

(1) The perovskite-type composite oxide and other oxides constituting the film and the cured product of the borosiloxane resin have a heat resistance temperature of at least 200 yen.

℃ or higher, has excellent adhesion to the metal base material, there is no fear of peeling, and the heater temperature and cooking chamber inner temperature can be much higher than conventional methods.

(2) Perovskite-type composite oxides have an oxidation activity comparable to that of platinum, and can impart S and C1 abilities to the film in order to oxidize and decompose oily hydrocarbon compounds generated during cooking. can. Moreover, since the internal temperature of the cooking chamber can be made higher than before, the rate of oil decomposition is further accelerated.

(3) The coating has a high emissivity of infrared rays, with a wavelength of 2 to 7 μm.
The emissivity is approximately 0.8, and the emissivity is approximately 0 at a wavelength of 7 to 30 μm.
．． It is 9 or more. Metal base material with emissivity of 0.1 to 0
．． Since the radiation rate is about 3, it is very advantageous to have a high radiation rate in radiation type cooking devices such as ovens and grills.

4) Since the film thickness of the above film is very thin at an average of 10 pm, there is no cracking of the film itself due to thermal cycles.

Example Examples of the present invention will be described below.

Since the film is formed on the metal substrate by a painting method, the work at that time is simply: (1) turning the film constituent material into a paint, (2) degreasing the metal substrate, (
3) Painting, (4) Baking process.Therefore, below:
The selection of materials, coating, coating methods, and baking conditions will be described, and the physical properties of the film, S, C, performance, etc. will be explained.

Material selection Other oxides: ZrO2 1j203 Fe203llMn○2・Cu.

As borosiloxane resin was selected. Details are shown in Table 1.

Table 1 Paint Table 2 shows the blending ratio of each material for making the paint.

Table 2 The above-mentioned composition was stirred for about 2 hours using an agitator (attritor) to form a paint.

Painted/baked metal substrates are degreased with solvent or alkaline in advance, and then painted using a one-way spray method. Baking at 200-250°C
The temperature was further increased to 400'C for 30 minutes.

Through the above steps, a coating was formed on the ceiling and bottom surfaces of the cooking chamber. (FIG. 1) Physical Properties of Coating Table 3 shows the physical properties of the coating according to this example, and FIG. 2 shows the infrared spectral emissivity at about 500°C.

Table 3 *Varies depending on firing conditions.

The above characteristics cannot be obtained with enamel.

As can be seen from Figure 2, the emissivity of the coating is 0.8 to 0.
Although it is high at 9, this is F e 203 ・M n O2 ・
Cu O.

It makes good use of the diffusion and absorption of infrared rays by oxides such as Al2O3 and ZrO2, especially Fe2O3 and Mn.
O2.CuO significantly improves the emissivity on the short wavelength side of 2 to 7 μm, and Al2O3 and ZrO2 rather improve the emissivity on the long wavelength side of 7 to 30 μm.

S, C, characteristics Figure 3 shows the S, C, characteristics of the surface of the famous species. The test was carried out by setting a hot plate at an arbitrary temperature, thereby keeping the temperature of the samples on various surfaces constant. There,
After dropping a certain amount of salad oil and leaving it for a certain period of time, another drop of salad oil was added. This operation was repeated 10 times, and the weight increase of the sample before and after the test was measured, and this was taken as the residual amount of salad oil. Therefore, it can be said that the smaller this residual amount is, the better the S, C, and performance are.

It can be seen from FIG. 3 that the S, C0 characteristics of the coating according to this example are superior to those of conventional S, C, and enamel.

Speed of temperature rise in the cooking chamber of a cooking device The faster the temperature rise in the cooking chamber of a cooking device such as an oven or grill, the better. This is because it shortens cooking time and saves energy. FIG. 4 shows an example of a temperature rise curve inside the oven chamber. As can be seen from this, the temperature rises much faster in the oven coated with the film of this example than in the conventionally used ovens coated with S, C, and enamel.

The reason for this is that the coating has a high emissivity and excellent heat resistance, so the temperature of the heater itself can be raised.

Details of the invention As explained above, according to the present invention, the following effects can be obtained.

(1) The film can be formed at low cost through a relatively simple process of converting the material into paint, painting, and baking, and has high cost performance.

(2) Due to its high performance, the gas generated from the cooker can be cleaned and it is hygienic.

(3) Since the infrared emissivity is high and the coating film has poor physical properties, the temperature in the cooking chamber increases quickly, shortening cooking time, saving energy, and further expanding the cooking menu.

[Brief explanation of drawings]

FIG. 1 is an enlarged cross-sectional view of the main part of the contact area between the coating of the cooking device and the metal base material in one embodiment of the present invention, FIG. 2 is an infrared spectral radiation characteristic diagram of the coating of the cooking device at 500°C, The figures are S and C9 characteristic diagrams at various temperatures of various surfaces, and FIG. 4 is a temperature rise diagram in the cooking chambers of the same cooker and a conventional cooker. 1...Borosiloxane resin cured body, 2...
La0,9CeQ, lCoO3,3---・Al2O3
or ZrO2 or Fe2O3”MnO, )・CuO
1jl-...Metal base material, 5...Coating, 6...
...Metal base material, 7...Coating, 9...
Coating. Name of agent: Patent attorney Toshio Nakao and one other person

Claims (1)

[Claims] A film is formed on the surface of a metal base material forming a cooking chamber of a cooking device, and the film is made of a perovskite type oxide, which is a composite oxide of a rare earth element and a metal element, and Zr, Ti, Si, and Al.
at least one oxide selected from the element group F
A cooking device having both oil-decomposing ability and infrared radiation ability, which is composed of at least one oxide selected from the group of elements e.g., Co, Ni, Mn, and Cu and a cured product of borosiloxane resin.