KR101307757B1 - Cooking device - Google Patents

Abstract

The present invention relates to a cooking appliance that is easy to clean the cooking chamber. To this end, the present invention forms a space for cooking food in the cooker main body, the inside of the cooker main body, the inner wall exposed to the food is combined with the cooking chamber, the surface of the cooking surface, the cooker main body and opening and closing the cooking chamber To provide a cooking device including a door for controlling the control unit for cooking the main body of the cooker for cooking the food.

According to the present invention, it is possible to easily clean the inside of the cooking chamber even at a low temperature, thereby reducing the time and power consumption required to clean the inside of the cooking chamber.

Cooker, Plasma, Surface Treatment, Atmospheric Pressure

Description

Cooking device

1 is a perspective view showing an embodiment of a cooking appliance according to the present invention.

2 is a view schematically showing an embodiment of a plasma processing apparatus used for manufacturing a cooking appliance according to the present invention.

Figure 3 is a view showing another embodiment of the electrode unit provided in the plasma processing apparatus used for manufacturing the cooking apparatus according to the present invention.

Figure 4 is a view showing another embodiment of the electrode unit provided in the plasma processing apparatus used for manufacturing the cooking apparatus according to the present invention.

5a to 5c are drawings showing the wettability of the plasma-treated substrate.

Figure 6 is a graph showing the cleaning performance of the cooking appliance according to the invention.

Description of the Related Art

10: cooking appliance body 20: door

30: second heating device 40: rack supporter

50: cooking chamber 51: inner wall

60: rack 70: third heating apparatus

80: tray 100: substrate

140: first electrode 160: second electrode

The present invention relates to a cooking appliance, and more particularly, to a cooking appliance having improved cleaning properties and a control method thereof.

In general, there are a variety of products, such as oven, microwave oven. A microwave oven is a device that includes only a magnetron or cooks food using a magnetron and a heater. In addition, the oven is a cooking utensil designed to cook food by drying and sealing the cooking material after heating. As a heat source for supplying heat to the food, electricity or gas fuel is used.

The cooking apparatuses include a cooking appliance body forming an appearance, a cooking chamber forming a space in which food is accommodated, a door for opening and closing the cooking chamber, and a heating device for cooking the food.

The cooking chamber is a cooking space formed inside the oven body, and the door is hinged to the front surface of the cooking appliance body to open and close left and right or up and down. In addition, the heating device is provided on one side inside the cooking chamber, and supplies heat energy for cooking food. The heat energy generated by the heating device is transferred to the food in the form of convective heat transfer or radiant heat transfer.

However, the above-described conventional cooking appliance has the following problems.

First, the conventional cooking appliance operates the heating apparatus at a high temperature, for example, at least 450 ° C. for 2 hours or more to remove the contaminants such as oil generated when cooking foods on the inner wall of the cooking chamber. Burn contaminants As such, if the inside of the cooking chamber is maintained at a high temperature for a long time, power consumption consumed by the heating apparatus reaches a considerable amount, and there is a problem in that the user is restricted in time to use the cooking apparatus.

Second, when the inside of the cooking chamber is maintained at a high temperature due to the high temperature cleaning function used in the conventional cooking appliance, the temperature of the door glass located in the front part of the cooking chamber is also increased. Since the door glass is directly exposed to the user, the user may be burned due to the high temperature door glass.

Third, as in the conventional cooking appliance, the higher the temperature inside the cooking chamber, the thicker the heat insulating material for blocking thermal energy leaking to the outside. When the thickness of the insulation is thick, not only the manufacturing cost of the product increases but also the space of the cooking chamber is relatively small.

The present invention has been made to solve the above problems, an object of the present invention is to provide a cooking apparatus that can easily clean the inside of the cooking chamber in a low temperature environment.

Another object of the present invention is to provide a cooking apparatus capable of reducing power consumption and cleaning time inside the cooking chamber.

 Still another object of the present invention is to provide a cooking apparatus capable of increasing a space of a cooking chamber in which food is cooked.

In order to achieve the above object, the present invention forms a cooking appliance main body, a space for cooking food in the interior of the cooking appliance main body, the inner wall exposed to the food is plasma cooking surface, combined with the cooking appliance main body And a door for opening and closing the cooking compartment, and a control device for controlling the cooker main body for cooking the food.

The cooking apparatus may further include a tray installed inside the cooking chamber, the surface of which includes a portion on which food is placed, on which a plasma surface is treated.

The inner wall is preferably plasma surface treated under atmospheric pressure.

The inner wall may be plasma surface treated on the surface of the enamel material.

The physical property of the inner wall is preferably determined according to the surface treatment conditions including the atmosphere gas supplied during the plasma surface treatment.

The cooking apparatus may further include a water supply device for supplying steam or water to the cooking chamber to clean the interior of the cooking chamber after cooking food.

Hereinafter, a preferred embodiment of a cooking appliance according to the present invention will be described in detail with reference to the accompanying drawings.

1, an embodiment of a cooking appliance according to the present invention will be described in detail.

The cooking appliance includes a cooking appliance body 10, a cooking chamber 50 forming a space for cooking food, a door 20 for opening and closing the cooking chamber 50, and a control unit for controlling the cooking appliance main body 10. A control device (not shown), and a heating device for cooking the food.

The control panel 2 for controlling the cooker is installed at the upper front of the cooker main body 10. The control panel 2 is connected to the control device provided inside the cooker main body. Of course, the control panel 2 may be provided separately from the cooker main body to adjust the control device at a long distance.

In addition, a transformer (not shown) is installed inside the main body of the cooker to supply electric power according to the type of food. The transformer is connected to the control device and made adjustable by the user. For example, when the user selects a method for cooking food on the control panel 2, the control device connected to the control panel controls the power supplied to the heating device by adjusting the transformer.

The heating device may be exposed to the cooking chamber 50 or may be provided inside the cooking appliance body. Heat energy generated by the heating device is transferred to the food by convection or radiation.

The heating device includes a first heating device (not shown) installed above the cooking chamber, a second heating device 30 installed behind the cooking chamber, and a third heating device 70 installed below the cooking chamber. It includes.

The first heating device is for heating the food by emitting infrared rays and is mainly used for baking food. As the first heating device, a magnetron or a heater is used. The first heating device is preferably fixed to the upper portion of the cooking chamber. Of course, the first heating device may be installed to be movable in the upper portion of the cooking chamber.

The second heating device 30 is located on the side inner wall of the cooking compartment facing the door 20, and auxiliary heat supply to the food placed in the cooking chamber. A blowing fan (not shown) is installed around the second heating device 30 to allow the heat generated by the second heating device to flow into the cooking chamber. The blowing fan serves to distribute the air heated by the second heating device evenly in the cooking chamber.

The third heating device 70 includes a heat generating member 71 for generating heat and a support member 73 for supporting the heat generating member 71. The third heating device 70 is located under the rack 60 and may be used as a heat source for baking bread or cakes.

The space heated by the third heating device 70 may be limited to a space for baking bread or cake, not the entire space inside the main body of the cooking appliance. For example, the cooking chamber may be divided into spaces by a separate separator (not shown), and the third heating apparatus may heat only the space separated by the separator. As a result, the heating devices are selectively turned on / off according to the food cooking method to transfer the heat energy to the food.

In addition, a tray 80 on which food is placed may be installed in the cooking chamber 50. The tray 80 is detachably installed in the rack 60 that guides the tray 80. Of course, the tray 80 may be fixed inside the cooking chamber. In addition, the tray 80 may be a plasma surface treatment of the surface including the portion on which food is placed. Details related to the plasma surface treatment will be described later.

Meanwhile, the rack 60 in which the tray is placed is installed in the cooking chamber 50. Of course, food may be placed directly on the upper surface of the rack (60). The rack 60 may be installed according to the intention of the user. That is, the position of the rack is installed to enable the position adjustment in the interior of the cooker body.

Rack supporters 40 for supporting the rack 60 are installed at both ends of the rack 60. The rack supporter 40 includes a plurality of rack guides 43 on which the rack 60 can be supported, and a guide support member 41 for supporting the rack guide 43. The guide support member 41 is fixedly installed on the inner surface of the cooker main body, and the rack guide 43 is installed in multiple stages on the guide support member 41.

In addition, the door 20 for opening and closing the cooker main body is hinged to the front surface of the cooker main body 10. The door 20 may be installed to slide in the front of the cooker main body.

The door 20 includes a door frame 21 forming an edge of the door and a door glass 22 installed inside the door frame. A lower portion of the door frame 21 is hinged to the cooker main body, and a sealing member (not shown) may be installed on an inner edge of the door frame to block the inside and the outside of the cooker main body. . The door glass 22 is preferably made of a heat-resistant material that is transparent and resistant to heat so that a user can check the inside of the cooker main body.

On the other hand, the cooking chamber 50 is formed inside the main body of the cooking appliance 10, the inner wall 51 of the cooking chamber forms a predetermined space for cooking food, and is exposed to the food when cooking food.

The inner wall 51 of the cooking chamber is subjected to plasma surface treatment on an enamel base material, that is, a substrate. The inner wall of the cooking chamber has various physical properties by surface modification through plasma surface treatment.

The inner wall 51 of the cooking chamber is subjected to plasma surface treatment at atmospheric pressure, that is, atmospheric pressure, and surface modification is performed in the micro-unit area. In addition, the physical properties of the inner wall 51 are determined according to the surface treatment conditions including the atmosphere gas, voltage applied, pressure, etc. supplied during the plasma surface treatment.

In addition, the cooking appliance main body may further include a water supply device (not shown) for supplying water or steam to clean the inside of the cooking chamber 50 after the cooking of food is completed.

The water supply device includes a water tank in which water is stored, a pump for moving the water in the water tank into the cooking chamber, and a water spray nozzle for spraying water on the inner wall of the cooking chamber. Of course, the water supply device may include a water tank in which water is stored, a heater for heating the water to convert it into steam, and a steam injection nozzle for injecting steam into the cooking chamber.

The water supply device removes the contaminants fixed on the inner wall of the cooking chamber by spraying water or steam on the inner wall 51 of the cooking chamber having the property of (ultra) hydrophilicity or (ultra) water repellency through plasma surface treatment.

In detail, when the inner wall 51 of the cooking chamber has hydrophilicity, water penetrates between the inner wall 51 and the contaminants. The user can then easily separate the contaminants from the inner wall using a separate device.

On the other hand, when the inner wall 51 of the cooking chamber has water repellency, contaminants themselves are not easily fixed to the inner wall, and the water is sprayed onto the inner wall to easily separate the contaminants from the inner wall.

A plasma processing apparatus is used to plasma-treat the inner wall 51. The plasma processing apparatus generates a plasma at atmospheric pressure and modifies the surface of the substrate using the plasma. Of course, the inner wall may be plasma treated in a vacuum state.

With reference to FIG. 2, the plasma processing apparatus used for manufacturing the cooking appliance according to the present invention will be briefly described.

Plasma is a group of positively charged ions and negatively charged electrons, which are clustered together.

The principle of generating the plasma is briefly described as follows. When energy is applied to gas particles, that is, gas molecules or atoms, the outermost electrons move out of the orbit, and the gas particles are separated into positively charged ions and negatively charged electrons. These positively charged ions and negatively charged electrons gather to form a grouping activity. In general, an artificial plasma phenomenon occurring in a space is generated by an ionization reaction by electrons generated by electrical energy or free electrons in a space accelerated by an electric field and colliding with gas particles in the space.

Specifically, the gas emits light when the atmosphere gas is supplied between the two electrodes under atmospheric pressure, and then a high frequency, that is, a radio frequency is supplied. That is, glow discharge occurs when a high frequency resonance phenomenon is used, and the glow discharge can significantly lower the temperature than atmospheric pressure discharge of other methods.

Plasma generation techniques used for surface treatment include corona discharge, dielectric barrier discharge (DBD), RF discharge, microwave discharge, arc discharge, etc. in addition to the glow discharge.

In addition, the electrodes for generating the plasma include a gliding arc type, a pen jet type, and the like. The gliding arc type electrode generates a plasma by applying a direct current, an alternating current, or a pulse voltage between two electrodes arranged in the gas stream, and the pen jet type electrode is formed between the rod-shaped electrode disposed in the gas stream and the ring or cylindrical electrode. The direct current, alternating current, or pulse voltage is applied to the plasma and the plasma is emitted from the hole of the ring or cylindrical electrode.

Plasma surface treatment using plasma can be divided into surface cleaning, surface modification, surface etching, and surface deposition. The surface cleaning refers to a surface treatment in which gas particles ionized by plasma impinge upon the surface of a material by physical and chemical methods to evaporate or tear off foreign substances. Surface modification means changing the properties of the surface by inducing physical and chemical changes such as the formation of functional groups of gas components on the surface. Plasma etching means surface treatment using a specific atmosphere gas, such as oxygen (O ₂ ), carbon tetrafluoride (CF ₄ ), or the like, to remove or tear off components, such as silicon, of a specific material. Surface deposition injects two or more gases to form a plasma where ionized gases are deposited throughout the surface of the material.

By impinging or bonding the particles generated by the plasma on the surface of the workpiece, unnecessary materials or unnecessary portions of the surface of the workpiece can be removed. That is, the plasma surface treatment not only improves the wettability of the workpiece by the hydrophilization treatment or hydrophobic treatment, but also the etching, disinfection / sterilization / sterilization, and thin film processing of the workpiece (eg diamond). Fine processing of thin films, fine processing of carbon films similar to diamonds), and the like.

The plasma processing apparatus shown in FIG. 2 is a device for generating plasma at atmospheric pressure, hereinafter referred to as an atmospheric pressure plasma processing apparatus. The atmospheric pressure plasma processing apparatus includes a chamber 170 including a gas inlet 180 and a gas outlet 190, a stage 101 disposed in the chamber 170, on which a substrate 100 is mounted, and the stage ( 101) The first and second electrodes 140 and 160 are formed to face each other at a predetermined distance from the surface and the stage 101.

A gas supply device for supplying an atmosphere gas to the outside of the chamber 170 through a radio frequency (RF) power supply device 130 for applying a high frequency to the first electrode 140 and the gas inlet 180 ( 110 is installed. A filter 120 for filtering the atmosphere gas is installed between the gas inlet 180 and the power supply device 130.

Here, the second electrode 160 is grounded, and surfaces of the first and second electrodes 140 and 160 are protected by an insulator (not shown). The gas outlet 190 serves as a passage through which gases remaining after the plasma surface treatment on the substrate 100 are discharged.

At this time, the power supply device 130 is such that the voltage applied between the two electrodes is 100V ~ 90000V and the frequency is 10 to 10 ⁹ Hz. Atmospheric gas flowing through the gas inlet 180 is activated between various types of electrodes to form a plasma composed of ions, electrons, radicals and neutral particles. Of course, when the atmosphere gas is introduced into the chamber may be supplied after being heated to a predetermined temperature in advance.

The gas used here consists of any one selected from an inert gas, an oxidizing gas, a reducing gas, or a mixture thereof. Specifically, the gas is air, nitrogen (N2), oxygen (O2), argon (Ar), water (H2O), helium (He), carbon dioxide (CO2), nitrogen oxides, carbon tetrafluoride, ammonia, ethylene, ethylene chloride Use a variety of mixtures, such as or individually.

Here, in order to maintain the discharge in a large area, the atmosphere gas is preferably supplied evenly throughout. A mesh may be installed inside the chamber 170 to evenly introduce the atmosphere gas into the gas inlet 180.

In addition, the electrodes 140 and 1160 use aluminum, titanium, nickel, chromium, copper, tungsten, platinum, or the like having strong corrosion resistance and conductivity. Of course, a dielectric may be provided under the electrodes. When the discharge is difficult or when a strong discharge is required, the plasma may be generated by generating a desired discharge by adjusting the size of the dielectric.

The operation of the atmospheric pressure plasma processing apparatus will be described below.

The substrate 100 is positioned on the second electrode 160, the gas is supplied from the gas supply device 110 to the chamber 170 through the filter 120, and at the same time, a high frequency is applied to the first electrode 140. When is applied, the atmosphere gas between the first and second electrodes 140 and 160 is in a plasma state.

When electrical energy is applied to the molecules of the atmosphere gas present in the chamber 170, the ions or the radicals having high reactivity are generated as the outermost electrons of the molecule and the atoms are out of orbit due to the collision of the accelerated electrons. The ions and radicals thus generated are accelerated by continuous collisions and electrical attractive forces, impacting the surface of the material, breaking molecular bonds in the region of several micrometers, and cutting down a certain thickness inside the substrate surface, generating minute surface irregularities, and gas components. Physical and chemical changes such as the formation of functional groups will be induced.

At this time, the material formed on the substrate 100 is etched or surface treated according to the components of the atmosphere gas supplied from the gas supply device 110 and the intensity and waveform of the high frequency applied to the first electrode 140.

Referring to FIG. 3, another embodiment of the electrode unit provided in the plasma processing apparatus for manufacturing the cooking apparatus according to the present invention will be described.

The plasma processing apparatus is a device for generating a plasma at atmospheric pressure. The electrode units 240 and 260 included in the plasma apparatus are formed of a first electrode 240 and a second electrode 260 having opposite shapes to each other. Include. Here, a high frequency is applied to the first electrode 240, and the second electrode 260 is grounded.

When high frequency is applied to the first electrode 240, a plasma is formed between the first electrode 240 and the second electrode 260. The plasma contacts the specific portion of the substrate 200 to surface-treat the substrate 200. That is, the plasma processing apparatus according to the present embodiment may perform plasma surface treatment on a specific portion of the substrate.

In order to generate more abundant plasma, a plurality of linear electrode pairs of electrodes of the electrode units 240 and 260 may be provided.

Referring to Figure 4, another embodiment of the electrode unit provided in the plasma processing apparatus for manufacturing a cooking apparatus according to the present invention will be described.

The electrode part including the first electrode 340 and the second electrode 360 provided in the plasma processing apparatus is for plasma surface treatment of the edge portion of the substrate, and has an 'L' shape. The first electrode 340 is grounded, and a high frequency signal is applied to the second electrode 360. In some cases, a high frequency is applied to the first electrode 340 by changing the position of the electrode, and the second electrode 360 may be grounded.

In addition, in order to generate more abundant plasma, the electrodes of the electrode unit may be formed by providing a plurality of L-shaped electrode pairs. The shape of the electrode unit is not limited thereto, and may be configured differently according to the shape of the substrate or the shape of the portion to be subjected to the plasma surface treatment. For example, each electrode may be provided with an arc shape, and the two electrodes may be provided at regular intervals from each other. As a result, when the two electrodes are formed in an arc shape, the plasma generation region is wider than the straight electrode pairs, thereby reducing the time for plasma surface treatment.

5A to 5C, the wettability of the substrate subjected to the plasma surface treatment by the atmospheric pressure plasma processing apparatus used to manufacture the cooking apparatus according to the present invention will be described.

The substrate 100 subjected to the plasma surface treatment has different properties depending on the contact angle α in contact with the water droplets W. As shown in FIG. 5A, when the contact angle is 10 ° or less, it has superhydrophilicity with water. As shown in FIG. 5B, when the contact angle is 90 ° to 150 °, it has water repellency. As shown, when the contact angle is 150 ° or more, it has super water repellency. Of course, the maximum angle of the contact angle is 180 degrees.

In chemical surface modification, ions or electrons having high binding energy collide with chemically low binding energy to generate radicals or ions, and the surrounding ozone, oxygen, nitrogen and the like combine with carbon and hydrogen on the surface to form carbonyl groups, Functional groups with high polarity, such as carboxyl groups, cyan groups, hydroxyl groups, etc. are produced, and the surface is chemically modified to be hydrophilic.

In one example, a substrate having hydrophilic properties is surface treated by a plasma generated from a mixed gas of a monomer and a nonpolymerizable gas. Specifically, when acetylene (C ₂ H ₂ ) is used as the monomer gas and nitrogen (N ₂ ) is used as the polymerizable gas, and the ratio of the mixed gas (acetylene: nitrogen) is 1: 9, the surface of the substrate is hydrophilic. Have

In addition, as a heat treatment condition for hydrophilic surface modification, the initial pressure is 1000 mmHg, the operating pressure is 0.3 mmHg, the current is 800mmA, the treatment time is 90 seconds. The surface treatment conditions described herein use some of the various conditions related to hydrophilic treatment, and the present invention is applied even when the type of mixed gas, the mixing composition ratio and other treatment conditions are different.

The hydrophilic property of the surface of the substrate is directly related to the chemical properties of the surface of the polymer, and the polymer surface synthesized under the plasma of the mixed gas has a high surface energy to spread water well. The high surface energy that leads to the hydrophilic properties results from the hydrophilic functional groups of the surface layer. The hydrophilic functional groups include C-O, CO, (C = O), C-N, N-H, and the like. The presence of these functional groups was confirmed by x ray photoelectron spectroscopy (XPS) and Flouier Transformation Infrared Spectroscopy (FT IR) analysis.

Surface modification of the substrate to have hydrophilicity is not limited to the case of using a mixture of acetylene and nitrogen as described above, for example, using a gas such as nitrogen or oxygen as a non-polymerizable gas of hydrocarbon other than acetylene as a monomer. It may have various embodiments.

FIG. 6 compares the force required to remove contaminants fixed on the general enamel surface A with the force required to remove contaminants fixed on the plasma surface-treated enamel surface B under the same conditions. Here, the X axis represents the number of times the process of solidifying the contaminants and the process of removing the contaminants is repeated, and the Y axis represents the force required to remove the contaminants.

Referring to Figure 6, the contaminants fixed on the normal enamel surface, the force (a1) is required to remove the contaminants fixed on the enamel surface for the first time to remove the contaminants fixed on the enamel surface for the first time It requires about 1.25 times more force than the force (b1).

Subsequently, even when the contaminants were fixed and removed again on the same surface as the surface from which the contaminants were removed, the general enamel surface consumed 1.25 times as much force as the enamel surface treated with plasma.

On the other hand, in the case of testing the cleaning performance of the surface twice and then fixing the contaminants on the same surface and removing them again, the force (a2) required to remove the contaminants fixed on the normal enamel surface is the surface of the enamel surface treated with plasma. It can be seen that it requires about 1.75 times more force than the force (b1) required to remove the contaminants fixed on the surface.

Based on this, it can be seen that as the process of removing contaminants is repeatedly performed, the plasma surface-treated enamel surface is much better in cleaning than the general enamel surface.

In addition, the Vickers hardness of the general enamel surface is 400 ~ 500 Hv, the Vickers hardness of the plasma surface treated enamel surface is 500 ~ 600 Hv. In addition, the plasma surface-treated enamel surface has the heat resistance of the normal enamel surface and has a relatively soft surface. As a result, it can be seen that the enamel surface treated with the plasma surface is improved in hardness, heat resistance, cleaning performance, etc. of the inner wall as compared with the general enamel surface.

It will be understood by those skilled in the art that various changes in form and details may be made therein without departing from the spirit and scope of the invention as defined by the appended claims.

The cooking appliance according to the present invention has the following effects.

First, according to the present invention, it is easy to clean the inside of the cooking chamber by plasma-processing the inner wall of the cooking chamber. That is, in order to burn the contaminants fixed in the cooking chamber, there is an advantage of not having to heat the inside of the cooking chamber to a high temperature.

Second, since the inside of the cooking chamber does not need to be heated to a high temperature for cleaning the cooking chamber, the thickness of the heat insulating material for insulating the cooking chamber becomes thin, and the space of the cooking chamber is widened.

Third, there is no need to maintain the inside of the cooking chamber at a high temperature in order to burn the contaminants fixed inside the cooking chamber, thereby reducing the risk of burns and reducing power consumption. In addition, since it is not necessary to maintain the inside of the cooking chamber at a high temperature for a long time to burn the contaminants, there is an advantage that the time required for cleaning the cooking chamber is reduced.

Claims (6)

Cooker main body; A space for cooking food in the inside of the main body of the cooker, wherein the inner wall exposed to the food has a hydrophilic surface by plasma surface treatment on a surface of an enamel material; A door coupled to the cooking appliance main body to open and close the cooking compartment; And, And a control device for controlling the cooker main body for cooking the food. The method of claim 1, And a tray disposed inside the cooking chamber, the tray including a portion on which food is placed, the plasma surface-treated tray. The method according to claim 1 or 2, The inner wall is a cooking apparatus, characterized in that the plasma surface treatment under atmospheric pressure. delete The method of claim 3, Physical properties of the inner wall is determined according to the surface treatment conditions including the atmosphere gas supplied during the plasma surface treatment, And a hydrophilic surface of the inner wall of the cooking chamber is formed by subjecting the enamel substrate to plasma surface treatment with an acetylene: nitrogen = 1: 9 atmosphere gas. The method according to claim 1 or 2, And a water supply device for supplying steam or water to the cooking chamber to clean the inside of the cooking chamber after cooking food.

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