JP2012237509A - Heating cooker - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a wall surface material of a heating cooker, the material having excellent heat resistance and durability and facilitating removal of contaminant adhering to a wall surface in a heating chamber.SOLUTION: A heating cooker 11 includes a heating chamber 12 storing food and a heating means heating the food in the heating chamber 12. A wall surface material 14 constituting an inner face of the heating chamber 12 is composed of a metal substrate 29 and a coating layer 30 on the surface of the metal substrate 29, the coating layer comprising a hydrophilic material 31 that facilitates removal of contaminant, and a coloring material 32 that hides discoloration of the metal substrate 29. Thereby, as adhesion strength of contaminant, which is a juice, oil, seasonings or the like oozing out of food and adhering to the wall, can be decreased on cleaning, the contaminant can be easily removed and a clean state of the wall can be always obtained. As discoloration of the metal substrate 29 can be hidden by the coating layer 30, a beautiful appearance of the wall surface material 14 constituting the heating chamber 12 can be maintained for a long period of time.

Description

  The present invention relates to a heating cooker such as a microwave oven, and more specifically to a configuration of a heating chamber that improves the removal performance of contaminants soiled by cooking food and is excellent in heating efficiency.

  In heating cookers such as microwave ovens, the walls inside the heating chamber are contaminated by food that is scattered by cooking, juice from seasonings, etc., so remove these contaminants and keep them always clean and clean. There is a strong demand for it.

  Conventionally, in order to easily clean contaminants, this type of cooking device such as a microwave oven has a non-adhesive fluororesin formed on the surface of a wall material made of a metal member that constitutes the inside surface of the heating chamber. Yes (see, for example, Patent Document 1).

  FIG. 5 shows the structure of the wall material on the inner surface of the heating chamber constituting the conventional cooking device described in Patent Document 1. As shown in FIG. As shown in FIG. 5, the wall material 1 constituting the inside surface of the heating chamber has a non-adhesive film 3 made of a fluororesin having a thickness of about several tens of μm formed on the surface of a metal member 2 such as an aluminized steel plate. .

  On the other hand, there is also a technique in which contaminants attached to the wall surface of the heating chamber are oxidatively decomposed by a catalyst to keep the heating chamber clean without maintenance (for example, see Patent Document 2).

  FIG. 6 shows the configuration of the wall material on the inner surface of the heating chamber constituting another conventional cooking device described in Patent Document 2. As shown in FIG. As shown in FIG. 6, the wall material 4 constituting the inside surface of the heating chamber has a self-cleaning layer 6 including a catalyst that oxidizes and decomposes contaminants at a lower temperature than thermal decomposition on the surface of a metal member 5 of a stainless steel plate. Yes.

  This self-cleaning layer 6 can be obtained by applying a mixture of enamel glaze and a catalyst material such as iron oxide, manganese oxide, copper oxide on the surface of the metal member 5 and baking it, and has a film thickness of 100 μm. It is the above porous layer.

JP 2001-59617 A JP 2004-53212 A

  However, the conventional non-adhesive film made of fluororesin described in Patent Document 1 is an organic resin, so the film is soft and easily scratched when rubbed against the hard surface of a sponge used for cleaning. If it is high, there is a problem that the non-adhesive film peels off.

  In addition, in order to prevent scratches and peeling of the non-adhesive film, it is necessary to wipe it lightly with the soft surface of the sponge, and there is a problem that it cannot be completely removed if the contaminants are firmly attached. It was.

In addition, the fluororesin used as the non-adhesive film has a heat resistance of about 280 ° C. or less, and the non-adhesiveness due to the thermal deterioration of the non-adhesive film is reduced by long-term use or for oven cooking at 300 ° C. or higher. There was a problem that it could not be used.

  On the other hand, the self-cleaning layer containing the catalyst according to the other conventional example described in Patent Document 2 sufficiently exhibits the catalytic effect of oxidatively decomposing contaminants unless the entire surface of the heating chamber is heated to a high temperature of 300 ° C. or higher. However, there is a problem that tarred contaminants remain.

  In addition, since the self-cleaning layer is porous, contaminants erode inside the self-cleaning layer, and it is impossible to completely remove contaminants that could not be oxidatively decomposed by the catalyst with a sponge. The problem is that the remaining contaminants become a source of off-flavors.

  Moreover, the enamel glaze and the composition of the catalyst material constituting the self-cleaning layer absorb energy in the microwave frequency band. In a cooking device that uses microwaves as the heating means, the microwave energy used to heat the food is reduced, so the heating efficiency of the food is degraded, the cooking time is increased, and more power is required. Had problems.

  Further, since the self-cleaning layer is formed by enamel processing, a high temperature of 800 ° C. or higher is required, and there is a problem that an aluminum-plated steel sheet having a low melting point cannot be used.

  The present invention solves the above-mentioned conventional problems, is excellent in heat resistance and durability, can easily remove contaminants attached to the wall surface of the heating chamber, and suppresses absorption loss of microwaves. An object of the present invention is to provide a wall material on the inner surface of a heating chamber that improves the heating efficiency of food.

  In order to solve the above-described problems, the heating cooker according to the present invention includes a heating chamber for storing food and a heating unit for heating the food placed in the heating chamber. The wall surface material constituting the inner surface of the metal substrate is composed of a metal base material, a hydrophilic material capable of easily removing contaminants on the surface of the metal base material, and a coloring material that conceals the color of the metal base material. And a coating layer.

  As a result, even if the juice, oil, seasonings, etc. from the food during cooking are scattered and contaminated on the wall surface material constituting the inner surface of the heating chamber, the surface of the metal base material which is the wall surface material of the present invention is made hydrophilic. Since the coating layer made of an excellent hydrophilic material is formed, the familiarity between water and the coating layer is good, water easily penetrates between the contaminant and the coating layer, and the adhesion of the contaminant is reduced. Contaminants can be easily removed.

  In addition, since the coating layer has excellent heat resistance even when the wall surface material including the metal substrate is exposed to a high temperature environment of 500 ° C. or higher, discoloration due to thermal oxidation of the metal substrate can be suppressed. In addition, the discoloration of the metal substrate can be concealed by including a coloring material made of a metal oxide having high heat resistance in the coating layer.

  The heating cooker according to the present invention forms a coating layer of a hydrophilic material and a coloring material on a metal substrate on the inner surface of the heating chamber, even if the inner surface of the heating chamber is contaminated by juice, oil, seasonings, etc. from food during cooking Since it is comprised with the wall material which carried out, the removal of the adhering contaminant can be performed easily and the heating chamber inner surface can always be made into a clean state.

In addition, even when exposed to harsh high-temperature environments such as oven cooking and self-cleaning heating, the discoloration of the metal substrate can be suppressed and the discoloration can be concealed. It can be maintained for a long time.

Side surface sectional drawing of the heating equipment cooker in Embodiment 1 of this invention The partial cross section figure of the wall surface material which comprises the heating chamber in Embodiment 1 of this invention Partial sectional view of the coating layer in the first embodiment of the present invention Partial sectional drawing of the wall surface material which comprises the heating chamber in Embodiment 2 of this invention Partial cross-sectional view of a wall material constituting a conventional heating chamber Partial sectional view of wall material constituting another conventional heating chamber

  1st invention is a heating cooker provided with the heating chamber which accommodates a foodstuff, and the heating means which heats the foodstuff mounted in the said heating chamber, The wall surface material which comprises the inner surface of the said heating chamber is metal It has a base material, and the coating layer which consists of a hydrophilic material which can remove a contaminant easily on the surface of the said metal base material, and the coloring material which conceals the color of the said metal base material.

  As a result, even if juice, oil, seasonings, etc. from food during cooking are scattered and contaminated on the wall surface material that constitutes the inner surface of the heating chamber, the water and the coating layer are familiar, so the water is covered with the contaminants. Since it easily penetrates between the layers and can be easily removed by reducing the adhesion of contaminants, a cooker that is always in a clean state can be realized.

  In addition, since the coating layer has excellent heat resistance even when the wall surface material including the metal substrate is exposed to a high temperature environment of 500 ° C. or higher, discoloration due to thermal oxidation of the metal substrate can be suppressed. The coating layer contains a coloring material made of a metal oxide having high heat resistance. Thereby, discoloration of a metal base material can be concealed and the aesthetics in a cooking appliance can be maintained over a long period of time.

  In the second invention, in particular, the metal substrate of the first invention comprises at least one of a steel plate, an aluminum plate, and a surface-treated steel plate provided with a plating layer. As a result, even if it is affected by thermal oxidation during the formation of the coating layer, it has excellent heat resistance and corrosion resistance, so discoloration and corrosion can be suppressed, and adhesion to a strong coating layer is realized. Therefore, the durability of the wall surface material can be improved.

In the third invention, in particular, the coating layer of the first or second invention contains SiO ₂ having hydrophilicity. Thereby, since high heat resistance and abrasion resistance can be realized, excellent durability can be realized.

  In the fourth invention, in particular, the coating layer of the first or second invention contains a metal oxide having a coloring action. Thereby, since heat resistance can be improved, concealment of the discoloration of a metal base material can be maintained for a long period of time, and the fall of the beauty | look in a cooking appliance can be prevented.

  In the fifth invention, in particular, the coating layer of any one of the first to third inventions has a thickness of 1 μm or less. Thereby, the absorption loss of the microwave by a wall surface material can be suppressed significantly, and cooking performance can be improved.

  Hereinafter, embodiments of the present invention will be described with reference to the drawings. Note that the present invention is not limited to the embodiments.

(Embodiment 1)
FIG. 1 shows a cross-sectional view as viewed from the side of the heating cooker according to Embodiment 1 of the present invention.

  In FIG. 1, a heating cooker 11 is a main body of a heating cooker having a heating chamber 12 therein, and the heating chamber 12 is a wall surface made up of an open / close door 13 and a bottom plate, a side plate, an upper plate, and a rear plate for taking in and out food. The material 14 is comprised. An upper heater 15 and a lower heater 16 are provided in the heating chamber 12, and the food 18 placed on the net 17 is heated so as to be sandwiched between the upper heater 15 and the lower heater 16.

  Behind the heating chamber 12 is provided a magnetron 19 for generating microwaves, which is a means for heating the food by microwaves, and heating the food by supplying at least one of microwaves and radiant heat and convection heat of the upper and lower heaters. It can be processed.

  The upper heater 15 is provided with an upper heater thermocouple 20 so as to be in contact with the surface thereof, and the upper heater thermocouple 20 is covered with a metal tube so as not to be affected by the microwave from the magnetron 19. The heater radiation amount detecting means is configured. Further, a lower heater thermocouple 21 is similarly provided on the surface of the lower heater 16 and serves as a heater radiation amount detecting means.

  The heating chamber 12 is provided with a thermistor 22 which is an internal temperature detecting means, and the upper heater thermocouple 20, the lower heater thermocouple 21 and the thermistor 22 are electrically connected to the control means 23, respectively. Based on the output, the amount of heating can be controlled by controlling the energization of the upper heater 15 and the lower heater 16.

  The rotating antenna 24 is a radio wave agitation means for irradiating the heating chamber 12 with the microwave generated from the magnetron 19. The microwave generated from the magnetron 19 is transmitted to the rotating antenna 24 and supplied into the heating chamber 12 while being stirred from the rotating antenna 24.

  The magnetron 19 and the rotating antenna 24 are provided on the rear and top surfaces of the heating chamber 12, but are not limited thereto, and may be provided on the bottom or side of the heating chamber 12.

  The exhaust port 25 provided at the upper part of the side wall in the heating chamber 12 is for ventilating the air in the heating chamber 12, and ventilates with the exhaust outlet 26 provided to communicate with the outside of the heating cooker 11. The fan 27 and the exhaust passage 28 are connected to each other, and the air in the heating chamber 12 is discharged outside the main body of the heating cooker 11.

  FIG. 2 is a partial cross-sectional view of wall surface material 14 constituting the inner surface of the heating chamber according to Embodiment 1 of the present invention.

  In the figure, the wall surface material 14 constituting the inner surface of the heating chamber 12 includes a hydrophilic material capable of easily removing contaminants on the surface of the metal base material 29 and a coloring material for concealing the discoloration of the metal base material. A coating layer 30 having a hydrophilic property is formed. In addition, hydrophilicity here is that a contact angle with water is 20 degrees or less.

  As the metal base material 29, since it becomes the skeleton of the heating chamber 12 of the heating cooker, a steel plate such as stainless steel, an aluminum plate, and a steel plate mainly composed of iron, such as stainless steel, which are excellent in workability and mechanical strength, are made of aluminum or zinc. It is desirable to use a surface-treated steel plate plated with.

Even if these metal base materials 29 are affected by thermal oxidation during the formation of the coating layer 30,
Since the corrosion resistance is excellent, discoloration and corrosion can be suppressed, and adhesion with the strong coating layer 30 can be realized, so that the durability of the wall surface material can be improved.

  FIG. 3 is a partial cross-sectional view of coating layer 30 according to Embodiment 1 of the present invention. In the figure, the coating layer 30 is composed of a hydrophilic material 31 and a coloring material 32, and the particles of the coloring material 32 are dispersed in the hydrophilic material 31.

  When the food is cooked, the wall material 14 is contaminated by the scattering of juice, oil, seasonings, and the like from the heated food.

  Conventionally, as a wall material of this type of cooking device, a metal base material having a non-adhesive film containing a fluororesin formed thereon is often used. This is because the fluororesin has an excellent water repellency and therefore has a weak adhesive force with contaminants and can be easily removed.

  However, when the cooking temperature is increased, contaminants such as oil are tarred by the polymerization reaction, and the contaminants adhere firmly even to the fluororesin. In order to remove this stubborn dirt, if a cleaning member such as a sponge used for cleaning is strongly pressed and rubbed, there is a problem that a non-adhesive film containing a fluororesin is scratched or peeled off. It was.

  In addition, when the wall surface material is used at a temperature of 280 ° C. or higher, the fluororesin is thermally deteriorated and the water repellency is lowered. Therefore, the non-adhesive film containing the fluororesin is limited to use at 280 ° C. or lower Met.

  Unlike the non-adhesion film | membrane containing a fluororesin, the coating layer 30 applied to this Embodiment can express hydrophilicity by containing the hydrophilic material 31. FIG.

  For this reason, the covering layer 30 is familiar with water, and when cleaning the wall surface of the heating chamber 12, the water to be used penetrates between the covering layer 30 and the attached contaminants, and the adhesive strength of the contaminants is significantly reduced. Therefore, contaminants can be easily removed, and a heating chamber that is always clean and clean can be realized.

Examples of the hydrophilic material 31 include siliceous (SiO ₂ ) formed by a sol-gel method, and an oxide containing silicon and zirconium. In order to maintain hydrophilicity over a long period of time, a composite oxide of silicon and zirconium is used. Is suitable.

Further, since the hydrophilic material 31 is composed of an inorganic compound containing siliceous (SiO ₂ ), it has high heat resistance and can maintain hydrophilic properties even in a temperature environment of 500 ° C. or higher. Since the hardness of the layer 30 can be increased, the wear resistance is excellent and the durability can be improved.

  On the other hand, when the heating cooker 11 is used at a high temperature such as oven cooking, the metal base material 29 constituting the wall surface material 14 is oxidized by heat and causes discoloration due to generation and growth of an oxide film.

  Since the coating layer 30 is formed on the surface of the metal base material 29, the discoloration of the metal base material 29 progresses more slowly than in the case without the coating layer 30, but the discoloration is conspicuous in long-term use. It becomes.

The covering layer 30 of the present embodiment includes a coloring material 32 in addition to the hydrophilic material 31. Since the coating layer 30 is colored by the coloring material 32 and the discoloration of the metal base material 29 can be concealed, the discoloration can be prevented from being changed in appearance, and the appearance of the wall surface material 14 constituting the heating chamber 12 can be prevented. Can be maintained for a long time.

  Examples of the coloring material 32 include metal oxide pigments. In particular, an oxide containing at least one of silicon, aluminum, titanium, zinc, copper, manganese, and iron with high heat resistance and chemical stability is preferable.

  By using this metal oxide as the coloring material 32, the heat resistance and chemical resistance can be improved, so that the concealment of the discoloration of the metal base material can be maintained for a long period of time, and the aesthetics in the cooking cabinet can be maintained. A decrease can be prevented.

  Some types of the heating cooker 11 have a thermal decomposition cleaning function that burns and cleans contaminants attached to the wall surface material 14 of the heating chamber 12.

  In this case, the temperature of the wall surface material 14 becomes a high temperature of 500 ° C. or more, and the discoloration of the metal base material 29 constituting the wall surface material 14 increases, but the coating layer 30 of the present embodiment is applied to the surface of the metal base material 29. By forming, a large discoloration can be concealed, so that the aesthetic appearance is not impaired, and the material constituting the coating layer 30 has a heat resistance of 500 ° C. or higher, so that excellent durability can be realized.

  In addition, the color of the coloring material 32 is not limited, It selects suitably from tops, such as market needs and design property.

  The covering layer 30 is preferably formed of a thin film. By forming the coating layer 30 as a thin film, dielectric loss in the microwave frequency band can be reduced, so that loss of microwave power can be suppressed and food heating efficiency can be increased. As a result, cooking time can be shortened and energy can be saved.

  In addition, the coating layer 30 needs to suppress absorption loss due to microwaves and maintain long-term adhesion with the metal base material 29, and after forming the coating layer 30, press working and bending work are performed. Since it is necessary to prevent peeling and cracks when performed, the film thickness of the coating layer 30 is preferably in the range of several hundred nm to 1 μm.

  Since the covering layer 30 is formed of a thin film having a thickness of 1 μm or less, it is possible to suppress a decrease in heat reflection characteristics of the metal base material 29, so that the radiant heat from the upper heater 15 and the lower heater 16 is effectively reflected. It is possible to cook food efficiently.

  In order to form the coating layer 30 into a thin film, the hydrophilic material 31 has a particle size of the starting material for film formation at the nm level, or by a hydration reaction or hydrolysis reaction of a silicon compound or a zirconium compound. The particle size to be generated needs to be on the nm level.

  Further, similarly to the hydrophilic material 31, the particle size to be generated for the coloring material 32 requires the nm level.

  The coating layer 30 having a film thickness of 1 μm or less can prevent peeling and cracking even if it is pressed or bent. Therefore, the coating layer 30 can be pre-coated, and after the metal base material 29 is processed into the shape of the heating chamber 12, the processing cost is lower than the post-coating for forming the coating layer 30 and the cost is reduced. be able to.

As the hydrophilic material 31 included in the coating layer 30, an oxide-based coating layer containing silicon and zirconium has been mentioned, but the material is not limited to this material, and the surface energy of the coating layer 30 is based on the wall material 14. A material that is smaller than the surface energy of the metal base material 29 or a material that increases the ratio of the surface energy of the contaminant particles to the surface energy of the coating layer 30 is applied.

  Even if welding is required when processing into the shape of the heating chamber 12, the covering layer 30 is a thin film, so that the weldability is not impaired. Caulking is desirable.

  Moreover, since this coating layer 30 can be made into a transparent film unless the coloring material 32 is used, by forming it on the glass surface inside the open / close door 13, the contamination resistance of the open / close door 13 is also improved. be able to.

(Embodiment 2)
FIG. 4 is a partial cross-sectional view of a wall material constituting the inner surface of the heating chamber according to Embodiment 2 of the present invention. The difference from the first embodiment is that a thick coating layer is provided instead of the thin coating layer 30.

  In the figure, the wall surface material 33 constituting the inner surface of the heating chamber 12 is composed of a hydrophilic material capable of easily removing contaminants having a film thickness of 1 μm or more on the surface of the metal substrate 29 and the metal substrate. A coating layer 34 having a hydrophilic property made of a coloring material that conceals discoloration is formed.

The coating layer 34 is obtained by applying a ceramic material composed of a hydrophilic material mainly composed of silica (SiO ₂ ), a metal oxide coloring material, and a binder to the surface of the metal substrate 29 and baking it. And a layer having a smooth surface with a thickness of several tens of μm.

  Unlike the non-adhesive film containing a fluororesin, the coating layer 34 applied to the present invention has hydrophilicity, unlike the non-adhesive film containing a fluororesin, and is well-familiar with water and used during cleaning. Water penetrates between the hydrophilic coating layer 30 and the contaminants, and the adhesion of the contaminants can be significantly reduced, so that the contaminants can be easily removed.

  Moreover, since the coating layer 34 conceals the discoloration surface by the thermal oxidation of the metal base material 29 with the coloring material contained, even if it uses it for a long time as a cooking appliance, an aesthetic appearance is not impaired.

  Since the coating layer 34 in the present embodiment is thick, it takes a long time for the surface-treated steel sheet to be exposed to be exposed even if it is rubbed with a hard nylon bundle when cleaning the inside of the heating chamber 12. Therefore, durability superior to that of the coating layer 30 of the first embodiment can be realized.

  Further, by increasing the film thickness of the coating layer 34, the corrosion resistance of the metal base material 29 can be further improved, and the durability can be improved.

On the other hand, since the coating layer 34 is thick, the dielectric loss in the microwave frequency band is larger than that of the coating layer 30 of the first embodiment, and the loss of microwave power is larger. It is better to reduce the amount of materials other than the quality (SiO ₂ ) and make the film thickness as thin as possible.

In addition, since the coating layer 34 is cracked or peeled off when the pressing or bending process is performed after the coating layer 34 is formed on the metal base material 29, the precoat as in the first embodiment cannot be applied. It is necessary to form the coating layer 34 after processing the metal base material 29 into the shape of the heating chamber 12 in advance.

  The material of the coating layer 34 can be the same material as that of the coating layer 30, but the particle size of these materials does not have to be on the nm level and has a particle size of sub μm to several tens of μm. Can also be applied.

  In the first and second embodiments of the present invention, the microwave heating cooker is described as the heating cooker. However, the coating layer of the present invention is contaminated with food and seasonings such as an IH cooker, an electric oven, and a gas range. Applicable to all cookers.

  As described above in detail, the cooking device according to the present invention can easily remove contaminants by providing a hydrophilic coating layer on the wall surface of a cooking device that is contaminated with food and seasonings, and is hygienic. Therefore, it can be applied to household appliances and industrial equipment such as an inner pot of a rice cooker and a drum of a washing machine that require cleanliness in addition to cooking equipment.

DESCRIPTION OF SYMBOLS 12 Heating chamber 1, 4, 14, 33 Wall material 29 Metal base material 20 Upper heater thermocouple 30, 34 Cover layer 31 Hydrophilic material 32 Coloring material

Claims (5)

In a heating cooker comprising a heating chamber for storing food and a heating means for heating the food placed in the heating chamber, a wall surface material constituting the inner surface of the heating chamber is a metal base material and the metal A heating cooker having a hydrophilic material capable of easily removing contaminants on a surface of a base material and a coating layer made of a coloring material that conceals discoloration of the metal base material. The cooking device according to claim 1, wherein the metal substrate includes at least one of a steel plate, an aluminum plate, and a surface-treated steel plate provided with a plating layer. The cooking device according to claim 1 or 2, wherein the hydrophilic material contained in the coating layer contains SiO ₂ . The cooking device according to claim 1 or 2, wherein the coloring material contained in the coating layer contains a metal oxide. The cooking device according to any one of claims 1 to 4, wherein the coating layer has a thickness of 1 µm or less.

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