Manufacturing method for a microwave cooker with waterproof function and high-performance ceramic heating element.

Abstract

The present invention provides a method for manufacturing a microwave cooker equipped with a waterproof function and a high-performance ceramic heating element, comprising a metal heating pan, a waterproof sheet, and a ceramic waterproof and water-repellent blanket insulation material bonded together inside the main container. [Solution] According to the method for manufacturing a microwave cooker equipped with a waterproof function and a high-performance ceramic heating element, the waterproof structure of the main container, as well as the pressure regulating valve for releasing internal expansion pressure, the ceramic waterproof and water-repellent blanket insulation material, and the heating layer are provided with waterproof and water-repellent functions, thereby preventing water from entering the heating layer. Furthermore, the required heating temperature can be obtained by easily combining the mixing ratio of the heating layer composition.

Description

Technical Field

[0001] The present invention relates to a method for manufacturing a cooker for a microwave oven that cooks food by utilizing heat generation in which microwave is converted into thermal energy by irradiating a heating layer, which is a ceramic heating element composition, with microwave.

Background Art

[0002] As conventional technologies, there are a "heating cooker for a microwave oven equipped with a safety device" in Patent Document 1 below and a "ceramic heating cooker using microwave" in Patent Document 2 below.

[0003] In these technologies, by providing ventilation holes at the bottom of the main body container 4, it was possible to discharge the internal thermal expansion pressure. However, there was a problem that moisture entered the inside through the ventilation holes during the post-cooking water washing. The ceramic blanket heat insulating material is hydrophilic, and when it comes into contact with water, the moisture is immediately absorbed and the function of the heat insulating material is lost. Also, since the heating layer also uses a hydrophilic binder material (sodium silicate or fly ash), when it comes into contact with water, the structure collapses and the heating ability is lost.

[0004] In addition, in recent microwave ovens, the rated high-frequency output power is not constant. For the purpose of speeding up cooking and improving convenience, various high-frequency output products (such as rated high-frequency output of 200 W to 2400 W) have been put on the market. For example, for commercial use, microwave ovens with high output have been put on the market to shorten the cooking time, and for household use, microwave ovens with slightly lower output have been put on the market. Furthermore, even with the same high-frequency output, there may be a difference in the heating temperature depending on the manufacturer.

[0005] Low-power ranges take a long time to cook, while high-power ranges risk burning food, so microwave cookware needed a customizable heating element that could accommodate various power levels. However, conventional microwave cookware heating elements had a simple composition of mill scale, steelmaking slag, or magnetite (Fe3O4) particles with a binder added. Because all heating elements had the same heating power, this simple and uniform manufacturing method made it impossible to customize the temperature.

[0006] Furthermore, since food preparation utensils used daily must be washed after use, contact with water is unavoidable. While conventional technology includes warnings to avoid using dishwashers or immersion in water, if water accidentally enters through the ventilation holes at the bottom, the hydrophilic ceramic blanket insulation and heating layer become wet, resulting in a problem where heating does not occur even when microwaves are applied.

[0007] In particular, after the thermally expanding air generated during cooking is expelled through the vents, the inside of the main container becomes a low-pressure state. When immersed in water for cleaning in this state, the pressure difference causes the water to be rapidly drawn into the interior. [Prior art documents] [Patent Documents]

[0008] [Patent Document 1] Registered Patent No. 10-0937534 of the Republic of Korea [Patent Document 2] Registered Patent No. 10-1885955 of the Republic of Korea [Overview of the project] [Problems that the invention aims to solve]

[0009] The present invention was made to solve the problems of the above-mentioned prior art, and aims to provide a method for manufacturing a microwave oven cooker that can improve the heating performance of a microwave oven cooker by providing a waterproof structure for the main container, adding waterproof and water-repellent functions to the blanket insulation material and ceramic heating layer incorporated inside so that the heating layer does not get wet, and by separating the base binder manufacturing process and the heating layer manufacturing process so that a heating pan with customizable temperature that can correspond to the heating temperature of different microwave oven outputs can be easily combined and manufactured. [Means for solving the problem]

[0010] To achieve the above objective, the present invention has the following configuration. *Equipped with a waterproof structure consisting of a valve groove (41), a waterproof sheet (6), a pressure regulating valve (5), and a silicone packing (22): After removing the ventilation hole structure formed at the bottom of the main container, the main container (4) is provided with a valve groove (41), a waterproof sheet (6), and a pressure regulating valve (5). The first stage of the waterproofing system prevents water from entering the interior by tightly bonding the silicone packing (22) of the heating pan (2) to the silicone packing groove (43) of the main container. *Waterproof and water-repellent structure for protection of the heating layer: Since the heating layer (21) is the component that ultimately needs to be protected from water, a ceramic waterproof and water-repellent blanket insulation material (3) is provided to protect it, and a second-stage waterproof system is also provided that adds a water-repellent function to the heating layer. As a result, even if some water enters the main container, it is vaporized and discharged from the pressure regulating valve (5), so no decrease in heat generation occurs. *The manufacturing process of the base binder and heating layer for the production of the required high-performance, customizable heating layer: In conventional technology, the manufacturing stages of the heating layer are integrated, and all heating layers have the same heating power. However, in the present invention, a manufacturing process is established that allows the composition ratio to be changed according to the microwave oven with various high-frequency output powers. The manufacturing stages of the base binder and the heating layer (21) composition are separated, and a means is provided to manufacture by customizing and combining the composition ratios of Fe3O4 powder, fly ash, and mill scale that are involved in heating. [Effects of the Invention]

[0011] The application of the first and second stage waterproofing system structures according to the present invention has the effect of eliminating the problem of heat generation failure due to moisture.

[0012] Furthermore, according to the present invention, it becomes possible to manufacture heating layers composed of high-heat, medium-heat, and low-heat compositions, enabling the manufacture of customizable heating cookers compatible with microwave ovens of various power outputs, thereby improving cooking satisfaction.

[0013] Furthermore, the mill scale, which is a component of the heating layer, has almost no viscosity even when mixed with the binder. 、 Because Fe3O4 powder and fly ash have a fine particle size, when mixed with a binder, their viscosity increases, improving their mixability, adhesion, and fluidity, which has the advantage of facilitating the molding and bonding processes of the heat-generating layer.

[0014] Furthermore, the cooking appliance manufactured according to the present invention achieves a heating temperature that is approximately 20-30% higher than that of conventional heating layers, resulting in reduced cooking time and improved cooking satisfaction.

[0015] Furthermore, while heating methods using gas flames as a heat source contribute to global warming due to fossil fuels that generate carbon dioxide, and to air pollution due to unburned gases in the room, the present invention uses a ceramic heating layer heated by microwaves instead of gas flames as a heat source, thus eliminating these problems and providing an environmentally friendly cooking appliance.

[0016] In addition to these, with the cooker manufactured according to the present invention, food is cooked with energy in which microwaves are converted into high-temperature bio far-infrared rays, thereby obtaining the effect of enhancing the original taste and aroma of the food.

Brief Description of the Drawings

[0017] [Figure 1] It is a flowchart showing the manufacturing stage of the present invention. [Figure 2] It is an exploded perspective view of the cooker manufactured according to the present invention. [Figure 3] It is a cross-sectional view of the cooker manufactured according to the present invention. [Figure 4] It is a view showing the heat-generating layer of the heat-generating pan according to the present invention. [Figure 5] It is a view showing the pressure regulating valve according to the present invention. [Figure 6] It is an enlarged view of the valve groove portion inside the main body container according to the present invention. [Figure 7] It is an enlarged view of the valve groove portion outside the main body container according to the present invention.

Modes for Carrying Out the Invention

[0018] Preferred embodiments of the present invention will be described in detail with reference to the accompanying drawings. In describing the embodiments of the present invention, matters not directly related to the technical features of the present invention, matters obvious to those skilled in the art, and parts applied repeatedly in each embodiment will be omitted from detailed description.

[0019] In addition, the terms described below are terms defined in consideration of the functions in the present invention, and may vary depending on the intentions or customs of users and operators, etc., so the definitions must be made based on the content throughout this specification that describes the present invention.

[0020] Furthermore, the diagrams and photographs presented illustrate a preferred embodiment of the present invention, and modifications by others, such as simple numerical or structural changes or substitutions with equivalent elements, should be understood to fall within the technical scope of the present invention.

[0021] The manufacturing steps according to the present invention are as shown in Figure 1, and the manufacturing steps described in more detail are as follows. [Manufacturing stage of the main container in which the valve groove is formed] Preferred materials for the main container 4 are heat-resistant thermoplastic resins, silicone rubber, ceramic materials, etc., and which transmit microwaves.

[0022] The valve groove 41 is formed at an arbitrary position on the bottom of the main container 4 and consists of a perforation 44 into which the pressure regulating valve 5 can be connected, a plurality of exhaust ribs 46 configured on a part of the inside of the main container so that air flows in the space between the ribs, and an exhaust port 47. A cap guard 49 is provided on the outside to maintain the normal assembly state of the pressure regulating valve 5.

[0023] Even if foreign matter such as residual insulation material comes into contact with the exhaust rib 46, the space between the ribs is configured so that airflow is not obstructed and expansion pressure is smoothly transmitted to the groove 56 of the pressure regulating valve 5.

[0024] [Waterproof sheet manufacturing stage] The waterproof sheet 6 is positioned between the bottom portion of the main container 4, including the valve groove portion 41, and the ceramic waterproof and water-repellent blanket insulation material 3. It is made of a material that has anti-tear properties, high heat resistance and heat insulation properties, and is also microwave-transmitting, such as a mica sheet.

[0025] Even if water flows in through the joint of the pressure regulating valve 5, the ceramic waterproof and water-repellent blanket insulation material will block the inflow of water to the bottom.

[0026] A preferred shape for the waterproof sheet 6(1) is such that the valve groove 41 and a portion of the bottom of the main container are covered, but the exhaust port 47 is left open and uncovered. As a result, the expanded airflow 71 in the sealed space 7 is connected to the pressure regulating valve 5 via the exhaust port 47 of the valve groove 41.

[0027] Another preferred shape for the waterproof sheet 6(2) is one in which the waterproof sheet 6 is placed on the mounting portion 48 of the main container and covers only the valve groove portion 41, leaving the exhaust port 47 open and uncovered.

[0028] In this invention, any of the waterproof sheets 6 can be appropriately selected depending on the characteristics of the finished product.

[0029] [Manufacturing stage of pressure regulating valve] The pressure regulating valve 5 of the present invention is a structure that discharges to the outside the thermal expansion pressure formed in a sealed space when the heating layer 21 is heated to a high temperature by microwave irradiation.

[0030] In particular, when moisture enters the interior, it is converted into steam and the pressure increases, so there is a risk that the main container will explode if the internal pressure exceeds a certain standard value. However, in this invention, unexpected accidents can be prevented by releasing the excess pressure.

[0031] A preferred pressure regulating valve 5 of the present invention is made of a silicone rubber material and has a support base 51 at the upper end, an intermediate support column 53, and a cap portion 52 at the lower end, with one or more exhaust passages 57 communicating between the support base and the support column.

[0032] The pressure due to thermal expansion is transmitted through the exhaust passage 57 to the groove 56 of the cap portion 52. When the internal pressure exceeds a certain reference value, the elasticity of the silicone rubber causes the curved portion 54 to automatically bend downward, forming a curved opening 55, through which the pressure is discharged to the outside.

[0033] The aforementioned silicone pressure regulating valve 5 has the advantage of occupying a small space and being easily replaceable and connectable without disassembling the assembled main body container.

[0034] Another preferred pressure regulating valve 5 of the present invention is a valve structure that opens and closes by spring elasticity, and includes a coupling member that is inserted into a valve through-hole and moves up and down according to the strength of the internal pressure, and is coupled to the main body container, and has a structure in which pressure is automatically discharged.

[0035] [Base binder manufacturing stage] The base binder manufacturing step is the manufacturing step of the precursor for producing the heat-generating layer composition, and is distinct from the manufacturing step of the heat-generating layer composition.

[0036] The main components of the base binder, sodium silicate, Fe3O4 powder, and fly ash, are hydrophilic, but when combined with the inorganic water-repellent agent added in this invention and dried and cured, they maintain their water-repellent properties even at high temperatures of 400-500°C.

[0037] A preferred base binder composition of the present invention comprises 30 to 50 parts by weight of sodium silicate, 1.5 to 2 parts by weight of 99% concentration acetic acid, 20 to 220 parts by weight of Fe3O4 powder, 10 to 70 parts by weight of fly ash, and 5 to 10 parts by weight of an inorganic water repellent, per 100 parts by weight of water, and is prepared by stirring.

[0038] The sodium silicate can be selectively used from among types 1, 2, 3, and 4 according to the Korean Industrial Standard (KSM1415), depending on the required SiO2 and Na2O content. In the embodiment of the present invention, type 2 sodium silicate is used, with SiO2 in an amount of 34 to 36 parts by weight and Na2O in an amount of 14 to 15 parts by weight.

[0039] The water resistance can be further enhanced by using sodium silicate containing potassium oxide (K2O) or lithium oxide (Li2O).

[0040] The addition of acetic acid to the sodium silicate is intended to generate crystalline silicate by stirring, thereby reducing the dissolution of the heat-generating layer structure in water. The acetic acid can be replaced with an acid solution such as conc-HCl of a certain content, and since the formation of silicate varies depending on the type, amount, concentration, and temperature of the acid, the appropriate type and ratio of additive can be selected according to the type of composition required.

[0041] Furthermore, the preferred Fe3O4 powder of the present invention has a particle size of 200 mesh or less to nanoparticles and a purity of 98% or higher.

[0042] The Fe3O4 powder is a ferromagnetic ceramic, and when mixed with mill scale and fly ash, dried, and cured, the microwave absorption rate of the heating layer improves, the heating temperature rises, the viscous bonding force increases, and the impact strength improves.

[0043] Furthermore, the fly ash of this invention is a fine powder produced during coal combustion, and because the particles are spherical, it acts as a ball bearing to reduce frictional resistance during molding. It also improves the durability and strength of the heating element through the pozzolanic reaction, enhances moldability, and contributes to increased productivity.

[0044] Furthermore, while increasing the fly ash content increases viscosity and improves moldability, it also has the characteristic of gradually decreasing exothermic temperature, so it is necessary to apply a suitable blending ratio.

[0045] Alternatively, silica sand may be mixed in instead of the fly ash mentioned above.

[0046] Furthermore, a preferred composition of the inorganic water repellent of the present invention is prepared by stirring, containing 5 to 7 parts by weight of hydrophobic nanosilica powder or aerogel powder per 100 parts by weight of a mixed solution of 10 to 90% by weight of N-octyltriethoxysilane and 10 to 90% by weight of tetraethoxysilane.

[0047] Furthermore, the method for stirring the base binder of the present invention is as follows. - Pour a specified amount of water into the agitator. - Add a specified amount of sodium silicate to the water and stir for 30 minutes to 1 hour. - Add a small amount of acetic acid to the stirred solution little by little while stirring for 30 minutes to 1 hour to generate and dissolve silicic acid. - A fixed amount of Fe3O4 powder and fly ash are added to the above solution and stirred for 1 hour. - A certain amount of inorganic water repellent is added to the above solution and stirred for 1 hour. The stirring speed in all of the above steps should be set to approximately 200 rpm to ensure uniform dissolution.

[0048] [Manufacturing stage of the heating layer composition] The manufacturing step of the heat-generating layer composition of the present invention is a step of adding a fixed amount of mill scale to the base binder and mixing it, wherein the mill scale is generated in the process of heat treatment of metal with ferromagnetic ceramics that absorb irradiated microwaves and convert them into thermal energy to generate high heat in a short time. 、 This is an oxide layer film containing Fe2O3, SiO2, Al2O3, FeO, etc.

[0049] A preferred heating layer composition of the present invention is formed by mixing 350 to 700 parts by weight of mill scale with respect to the total weight of the base binder.

[0050] The mill scale used as a heating element in this invention is a film obtained by crushing and sorting it so that it passes through a 3 mm mesh after removing foreign matter, and a mill scale with a high microwave absorption rate and an Fe2O3 and FeO content of 80-95% is used.

[0051] When the aforementioned heating layer composition is bonded to the heating layer of a heating bread and dried and hardened, the structure becomes porous.

[0052] The aforementioned porous structure has excellent resistance to thermal expansion and contraction, and can maintain adhesion to the bread even at high temperatures, thus improving the durability and heat resistance of the heating layer.

[0053] Therefore, by adjusting the content ratio of mill scale to the base binder composition of the present invention, a desired heating temperature of the heating layer can be obtained.

[0054] [Manufacturing process of heated bread] The heating pan of the present invention is manufactured by molding a heating layer composition to a predetermined shape, thickness, and weight and bonding it to the bottom of a metal pan, and then completely drying and curing it at 250-350°C for 25-30 minutes.

[0055] Furthermore, since the thickness, weight, and surface shape of the heating layer attached to the heating pan affect the heating temperature, the surface is structured into various shapes such as flat, concave, and convex to allow for adjustment of the heating temperature.

[0056] In other words, a convex heating layer bonded to a metal pan increases microwave absorption by 10-20% compared to flat or concave shapes, enabling higher temperatures.

[0057] Furthermore, by attaching the silicone packing 22 to the edge of the heating pan 2, the elastic silicone rubber packing is pressed into the gap between the silicone packing groove 43 of the main container and the silicone packing 22, thereby ensuring the waterproof function of the main container.

[0058] [Manufacturing, drying, and curing stages of the water-repellent coating agent for the heating layer] In the present invention, in order to obtain the water-repellent function of the heating layer, a manufacturing process can be carried out in which the heating layer is given a basic water-repellent function by an inorganic binder contained in the base binder, and preferably, a process can be carried out in which a water-repellent enhancing coating agent is further applied to the heating layer by spraying or the like, and then dried and cured to enhance the water-repellent properties. Therefore, during manufacturing, the basic process or the water-repellent enhancing process can be applied as needed.

[0059] In the case of the aforementioned inorganic water repellent, the small molecular size of the inorganic water repellent penetrates into the capillary voids of the porous heat-generating layer, and the water-repellent properties of the heat-generating layer can be enhanced by drying and hardening.

[0060] The additive components of the water-repellent enhancing coating agent for the aforementioned heating layer must be heat-resistant even at high temperatures of 400-500°C, and therefore must not contain organic compounds.

[0061] The composition of the water-repellent enhancing coating agent of the present invention is prepared by dissolving 100 parts by weight of a mixed solution of 10-90% by weight of N-octyltriethoxysilane and 10-90% by weight of tetraethoxysilane, along with 5-7 parts by weight of hydrophobic nanosilica powder or aerogel powder and 3-10 parts by weight of nanocarbon powder, by stirring.

[0062] After spraying the aforementioned water-repellent enhancing coating agent onto the surface of the heating layer, it is dried and cured in a tunnel-type drying oven at 250-350°C for 25-30 minutes, thereby imparting a highly heat-resistant penetrating water-repellent property. As a result, water that comes into contact with the surface of the heating layer beads up and rolls off, exhibiting a water-repellent phenomenon.

[0063] The nanocarbon powder, which is the main component added to the water-repellent coating agent of the present invention, plays a role in improving adhesion to the heat-generating layer and increasing surface hardness, thereby enhancing durability and heat resistance.

[0064] [Manufacturing stage of ceramic waterproof and water-repellent blanket insulation] The preferred waterproof and water-repellent blanket insulation material of the present invention wraps around the lower part of the heating pan 2 to prevent the high heat of the heating layer 21 from being conducted to the lower part or sides. The blanket structure is an inorganic porous ceramic fiber structure, a compressed blanket structure that does not contain any organic binders, manufactured by a spinning method, and is elastic.

[0065] The preferred ceramic waterproof and water-repellent blanket insulation material of the present invention is 、The blanket structure consists of a porous ceramic fiber blanket structure containing two or more components from Al2O3, SiO2, CaO, MgO, ZrO2, silicate groups, and alkoxysilane groups, and the blanket structure is surface-treated with hydrophobic silica material or contains it in the fiber structure components, thereby maintaining high thermal insulation and water repellency.

[0066] Another preferred thermal insulation material of the present invention is a water-repellent blanket made of a hydrophobic aerogel blanket.

[0067] The aforementioned ceramic waterproof and water-repellent blanket insulation material must maintain high-temperature heat resistance of 500°C or higher, possess insulating properties, and be a material that can transmit microwaves.

[0068] [Assembly stage] In the assembly stage of the finished product of the present invention, after connecting the pressure regulating valve 5 to the valve groove 41 of the main container 4, a waterproof sheet 6 is placed over it, a ceramic waterproof and water-repellent blanket insulation material 3 and a heating layer 21 are bonded on top of it, heating pans 2 to which silicone packing 22 is attached are sequentially placed, and the heating pans 2 are pressed downward so that the silicone packing 22 is tightly bonded to the silicone packing groove 43 of the main container to complete the assembly.

[0069] The main container 41 is made of heat-resistant silicone rubber, thermoplastic resin, ceramic material, etc. Typically, when the temperature rises, the main body made of plastic resin or silicone rubber undergoes thermal expansion of approximately 3 / 1000 to 30 / 1000, increasing the average distance between constituent particles and thus increasing the volume.

[0070] In the process of assembling the silicone packing 22 by making it tightly adhere to the packing groove 43, the present invention utilizes the phenomenon of thermal expansion of a material due to heating. That is, after preparing the inner diameter of the silicone packing groove 43 of the main container to be the same as or slightly smaller than the outer diameter of the silicone packing 22 bonded to the heating pan 2 at room temperature, the main container 4 is heated at an ambient temperature of approximately 100 to 150°C for 5 to 10 minutes, causing its volume to expand. The silicone packing 22 bonded to the heating pan 2 is then inserted and bonded to the expanded packing groove 43 of the main container 4 without damage. Subsequently, when the main container 4 returns to room temperature, its volume returns to its original state, and the peripheral edge of the elastic silicone packing 22 is pressed and pressure-welded, resulting in a tight, gap-free bond, thereby forming a waterproof structure that prevents water from entering.

[0071] Furthermore, regarding the bottom shape of the main container 4 and heating pan 2 of the present invention, it is preferable that a protruding end 45 of the main container is formed on the outside of the bottom of the main container.

[0072] Furthermore, it is preferable that a pan protrusion 23 is also formed on the outer bottom of the heating pan.

[0073] Because at least one of these structures is a protruding structure, when the heating pan 2 is pressed downwards against the main container 4, the outside of the ceramic waterproof and water-repellent blanket insulation material 3 is compressed more than the inside. As a result, the pores on the outside of the ceramic blanket insulation material shrink, making it difficult for moisture to be transferred to the heating layer, and thus further enhancing the waterproofing effect.

[0074] (Experimental Example 1) Waterproof Test of the Present *Testing institution: Korea Testing Certification Institute (KTC) [Table 1]

[0075] [result] As is clear from the above data, the waterproof performance was confirmed by the structure of the valve groove 41 of the main container, the waterproof sheet 6, the silicone packing 22 of the heating pan, and the pressure regulating valve 5 according to the present invention.

[0076] (Experimental Example 2) Comparison test of water repellency between conventional heating layer and the heating layer of the present invention. [Table 2]

[0077] [result] As is clear from the above photograph, - Conventional heating layers (Photo 1) are made of hydrophilic material, so when immersed in water, they quickly absorb moisture, and the adhesive force between tissues gradually decreases over time. -The heat-generating layer of the present invention (Photo 2) exhibits water-repellent properties even after being immersed for more than two weeks. - The inorganic water-repellent agent of the present invention maintains its water-repellent function even at high temperatures of 400 to 500°C.

[0078] (Experimental Example 3) Waterproofing and water-repellency comparison test between conventional ceramic blanket insulation and the ceramic waterproof and water-repellent blanket insulation of the present invention. [Table 3]

[0079] [result] As is clear from the above photograph, - Conventional ceramic blanket insulation (Photo 1) quickly absorbs water to a saturated state when immersed, losing its function as an insulating material. - The ceramic waterproof and water-repellent blanket insulation material according to the present invention (Photo 2) can be confirmed to have water-repellent properties even after being immersed for more than two weeks.

[0080] (Experimental Example 4) Temperature changes due to combinations of fly ash, Fe3O4 powder, and mill scale ratios that affect the exothermic temperature (1) [Table 4]

[0081] *Measurement of the highest point temperature with a heat generation error range of ±5%. [Experimental subjects] - Circular metal pan: Diameter 190mm, height 20mm, thickness 0.6mm - Heating layer used in the experiment: Circular, 150mm in diameter, 4mm thick [Experimental composition] -Basic composition: 100 parts by weight of water, 40 parts by weight of sodium silicate, 1.5 parts by weight of acetic acid (99% concentration), and 5 parts by weight of inorganic water repellent. - The basic binder composition contains fly ash 、 Temperature changes due to the addition of Fe3O4 powder and mill scale as shown in the table above.

[0082] (result) As can be seen from the heat generation temperature after 3 minutes of heating in the table above, the mixture with the proportions specified in experiment number (3) exhibits the highest heat generation.

[0083] (Experimental Example 5) Temperature changes due to combinations of fly ash, Fe3O4 powder, and mill scale ratios that affect the exothermic temperature (2) [Table 5]

[0084] *Measurement of the highest point temperature with a heat generation error range of ±5%. [Experimental subjects] - Circular metal pan: Diameter 190mm, height 20mm, thickness 0.6mm - Heating layer used in the experiment: Circular, 150mm in diameter, 4mm thick [Experimental composition] -Basic composition: 100 parts by weight of water, 40 parts by weight of sodium silicate, 1.5 parts by weight of acetic acid (99% concentration), and 5 parts by weight of inorganic water repellent. - Temperature change when fly ash, Fe3O4 powder, and mill scale are added to the basic composition as shown in the table above.

[0085] [result] As shown in the table above, it can be confirmed that various exothermic temperatures can be obtained by changing the composition.

[0086] (Experimental Example 6) Comparison of heating temperatures based on the rated high-frequency output of microwave ovens. [Table 6]

[0087] *Measurement of the highest point temperature with a heat generation error range of ±5%. [Experimental subjects] - Circular metal pan: Diameter 190mm, height 20mm, thickness 0.6mm - Heating layer: Circular, 150mm in diameter, 4mm thick [Experimental composition] - 100 parts by weight of water, 40 parts by weight of sodium silicate, 1.5 parts by weight of acetic acid (99% concentration), 5 parts by weight of inorganic water repellent, 10 parts by weight of fly ash, 20 parts by weight of Fe3O4 powder, and 700 parts by weight of mill scale.

[0088] [result] As shown in the table above, the difference in heating temperature due to the type of microwave oven and rated high-frequency output can be confirmed. [Industrial applicability]

[0089] As described above, the present invention is a method for manufacturing a highly efficient ceramic heating cooking utensil that utilizes microwaves, which is a ceramic heating element that uses microwaves to convert electrical energy, a secondary energy source, into environmentally friendly and highly efficient tertiary energy, thereby reducing greenhouse gas emissions by reducing carbon dioxide emissions, which are the main cause of global warming, generated from fossil fuel gas energy. It can be used in a variety of applications such as food cookers for microwave ovens, microwave dryers, food processing machines, and water heaters. [Explanation of symbols]

[0090] 1 lid 2 Heating bread 21 Heating layer 22 Silicone gasket 23. Bread protrusion 3. Ceramic waterproof and water-repellent blanket insulation 4. Main container 41 Valve groove 42 Legs 43 Silicone packing groove 44 Perforation part 45 Main container protruding end 46(1), 46(2) Exhaust Ribs 47 Exhaust port 48(1), 48(2), 48(3) Mounting section 49 Cap Guard 5. Pressure regulating valve 51 Support stand 52 Cap section 53 Pillar section 54 Curved section 55 Curved opening 56 groove 57 Exhaust passage 6(1), 6(2) Waterproof sheet 7 Closed space 71 Airflow

Claims

1. A method for manufacturing a food cooker that utilizes heat generated when microwaves are irradiated onto a ceramic heating layer, thereby converting the microwaves into thermal energy, A method for manufacturing a microwave cooker equipped with a waterproof function and a high-performance ceramic heating element, characterized by: connecting a pressure regulating valve (5) to a perforated portion of a main container (4) having a valve groove (41); placing a waterproof sheet (6) and a ceramic waterproof and water-repellent blanket insulation material inside; and then assembling a heating pan (2) on which a heating layer (21) mixed with a base binder or a heating layer (21) surface-treated with a water-repellent enhancing coating agent has been dried and cured and bonded, by connecting it to a silicone packing groove (43) of the main container (4).

2. The valve groove portion (41) is formed in the main body container (4), The perforated portion (44) into which the pressure regulating valve (5) is connected, Multiple exhaust ribs (46) formed on a part of the inside of the main body container (4), An exhaust port (47) defined by the space between the plurality of exhaust ribs (46), A mounting portion (48) is formed spaced apart from a part or one side of the plurality of exhaust ribs (46), A method for manufacturing a microwave cooker with a waterproof function and a high-performance ceramic heating element, characterized in that it comprises a cap guard (49) formed on the outside of the main body container (4) for coupling the pressure regulating valve (5), as described in claim 1.

3. The valve groove portion (41) is formed in the main body container (4), The perforated portion (44) into which the pressure regulating valve (5) is connected, Multiple exhaust ribs (46) formed on a part of the inside of the main body container (4), It is configured to include an exhaust port (47) defined by the space between the plurality of exhaust ribs (46), The connection between the heating pan (2) and the main container (4) creates a sealed space (7) between the heating pan (2) and the main container (4). The aforementioned waterproof sheet (6) is Displaced between the main body container (4) and the lower part of the ceramic waterproof and water-repellent blanket insulation material (3), A method for manufacturing a microwave cooker equipped with a waterproof function and a high-performance ceramic heating element, as described in claim 1, characterized in that the valve groove (41) is covered, but the exhaust port (47) is left open, allowing air to flow between the valve groove (41) and the sealed space (7), and the heating element is made of a highly heat-resistant insulating material that transmits microwaves.

4. The valve groove portion (41) is formed in the main body container (4), The perforated portion (44) into which the pressure regulating valve (5) is connected, Multiple exhaust ribs (46) formed on a part of the inside of the main body container (4), It is configured to include an exhaust port (47) defined by the space between the plurality of exhaust ribs (46), The pressure regulating valve (5) is It is made of an elastic silicone rubber material and is bonded to the perforated portion (44), It is composed of a support base (51) formed at the upper end, a cap portion (52) formed at the lower end, and a support column portion (53) connecting the support base (51) and the cap portion (52). The cap portion (52) has a groove (56) formed on its upper surface and a curved portion (54) along its periphery. The support base (51) and the support column (53) are provided with one or more exhaust passages (57) that are partially formed by cutouts. The method for manufacturing a microwave cooker equipped with a waterproof function and a high-performance ceramic heating element, as described in claim 1, characterized in that the pressure due to thermal expansion is transmitted to the groove (56) through the exhaust passage (57), the curved portion (54) bends to form a curved opening (55), and the pressure is discharged from the gap therethrough.

5. The pressure regulating valve (5) is A method for manufacturing a microwave cooker equipped with a waterproof function and a high-performance ceramic heating element, characterized in that it is a pressure release structure having a valve structure that opens and closes by spring elasticity, and includes a coupling member that is inserted into a valve through-hole and moves up and down according to the strength of the pressure, and is coupled to the main body container, thereby providing a structure in which pressure is automatically released.

6. The composition of the base binder is, Per 100 parts by weight of water, add 30 to 50 parts by weight of sodium silicate, 1.5 to 2 parts by weight of 99% acetic acid, 10 to 70 parts by weight of fly ash, and Fe ３ O ４ A method for manufacturing a microwave cooker equipped with a waterproof function and a high-performance ceramic heating element, characterized in that it comprises 20 to 220 parts by weight of powder and 5 to 10 parts by weight of an inorganic water repellent, and is stirred, as described in claim 1.

7. The Fe ３ O ４ The powder is A method for manufacturing a microwave cooker equipped with a waterproof function and a high-performance ceramic heating element, as described in claim 6, characterized in that it is in a nano-state of 200 mesh or less and has a purity of 98% or more.

8. The inorganic water-repellent agent is A method for manufacturing a microwave cooker equipped with a waterproof function and a high-performance ceramic heating element, characterized in that the solution contains 5 to 10 parts by weight of hydrophobic nanosilica powder or nanoaerogel powder per 100 parts by weight of a mixed solution of 10 to 90% by weight of N-octyltriethoxysilane and 10 to 90% by weight of tetraethoxysilane, and is an inorganic water repellent with high heat resistance, as described in claim 6.

9. The heat-generating layer has a composition ratio of metal oxide with a scale particle size of 3 mm or less per 100 parts by weight of the base binder. 、 Fe ２ O ３ A method for manufacturing a microwave cooker equipped with a waterproof function and a high-performance ceramic heating element, characterized in that it is a mixture containing 350 to 700 parts by weight of mill scale having an FeO content of 80 to 95%.

10. Water-repellent coating agents are A method for manufacturing a microwave cooker equipped with a waterproof function and a high-performance ceramic heating element, characterized in that 100 parts by weight of a mixed solution of 10 to 90% by weight of N-octyltriethoxysilane and 10 to 90% by weight of tetraethoxysilane is mixed with 5 to 7 parts by weight of hydrophobic nanosilica powder or nanoaerogel powder and 3 to 10 parts by weight of nanocarbon powder, and the mixture is stirred, as described in claim 1.

11. In the surface treatment of the aforementioned water-repellent enhancing coating agent, A method for manufacturing a microwave cooker equipped with a waterproof function and a high-performance ceramic heating element, as described in claim 1, characterized by spraying the water-repellent enhancing coating agent onto the surface of the heating layer, and then drying and curing it in a tunnel-type drying oven at 250 to 350°C for 25 to 30 minutes.

12. The method for manufacturing a microwave cooker equipped with a waterproof function and a high-performance ceramic heating element, as described in claim 1, characterized in that the heating pan is bonded to the bottom of a metal pan by shaping the surface of the heating layer composition into a flat, convex, or concave shape, and then dried and cured at 250 to 350°C for 25 to 30 minutes.

13. The aforementioned ceramic waterproof and water-repellent blanket insulation material (3) is Al ２ O ３ , SiO ２ , CaO, MgO, ZrO ２ A ceramic blanket heat insulating material or an aerogel blanket heat insulating material made of a porous fiber blanket structure containing two or more components selected from a silicate group, an alkoxysilane group, and having a hydrophobic silica material surface-treated on the fiber structure or contained in the fiber structure components, characterized in that it is a manufacturing method of a microwave cooker provided with the waterproof function and the high-performance ceramic heating element according to claim 1.

14. In the heating pan (2) assembly process (Process) in which a silicone packing (22) is bonded to a silicone packing groove (43) of the main container (4), the main container (4) is heated at an ambient temperature of 100 to 150°C for 5 to 10 minutes to expand the volume of the packing groove (43) by thermal expansion, and then the heating pan (2) is inserted and bonded, so that as the temperature of the main container (4) decreases to room temperature, the volume returns to its original state, the peripheral edge of the elastic silicone packing is pressed and pressure-welded, and a tight bond is formed without any gaps, as described in claim 1.

15. A method for manufacturing a microwave cooker equipped with a waterproof function and a high-performance ceramic heating element, characterized in that at least one of the main body container (4)'s protruding end (45) or the heating pan (2)'s pan protruding portion (23) is formed to compress the peripheral edge of the ceramic waterproof and water-repellent blanket insulation material (3) during assembly, as described in claim 1.

Images