Heating device and refrigerator equipped with heating device

Abstract

To provide a refrigerator that comprises a heating device capable of uniformly heating an object to be heated, and having high reliability and safety, and a storage space capable of easily thawing a frozen object as a stored object in a high-quality state.SOLUTION: A heating device according to the present invention comprises: an oscillating electrode provided on one side of a heating space for storing an object to be heated, and comprising an electrode surface in which an electric field concentration region is formed; an opposite electrode provided on another side of the heating space, and comprising an electrode surface opposite to the electrode surface of the oscillating electrode; and a high-frequency electric field forming part for forming a high-frequency electric field to be applied between the oscillating electrode and the opposite electrode.SELECTED DRAWING: Figure 2

Description

[Technical field]

[0001] The present invention relates to a heating device having a heating chamber capable of thawing frozen goods, and to a refrigerator equipped with the heating device. [Background technology]

[0002] A typical refrigerator is equipped with a freezer compartment and is used to freeze ingredients and foods and store them as frozen goods for long periods of time. It is desirable for such frozen goods to be thawed in a short time and used in cooking in a thawed state as close to fresh as possible.

[0003] There are thawing processes for thawing frozen foods, such as natural thawing at room temperature and thawing under running tap water, but these thawing processes do not satisfy the short-time thawing required by cooks. In general households, microwave cooking appliances, so-called microwave ovens, are used to thaw frozen foods in a short time. However, when thawing frozen foods in a microwave oven, although thawing in a short time is possible, there are cases where an undesirable thawing state occurs, such as so-called "partially cooked" in which high-frequency energy is concentrated in the previously thawed area and the food cannot be thawed uniformly. Thus, when thawing frozen foods using a microwave oven, it is not easy to obtain a desirable high-quality thawed state. Here, a high-quality thawed state refers to a thawed state that is not tasty as food, such as a "partially cooked" state.

[0004] Patent Document 1 discloses a refrigerator equipped with a high-frequency heating chamber configured to supply cold air and thaw frozen items while irradiating microwaves. In the refrigerator of Patent Document 1, the surface of the frozen items in the high-frequency heating chamber is covered with cold air, and the inside of the frozen items is thawed by irradiating microwaves to the frozen items. [Prior art documents] [Patent documents]

[0005] [Patent Document 1] JP 2002-147919 A Summary of the Invention [Problem to be solved by the invention]

[0006] The refrigerator disclosed in Patent Document 1 is provided with a magnetron for generating microwaves, and is configured to irradiate microwaves to frozen items in a high-frequency heating chamber for microwave heating. The refrigerator in Patent Document 1 is configured to be large overall as a result of the magnetron, which is a microwave generating means, and its cooling mechanism, making it difficult to reduce the size of the refrigerator. In addition, since the refrigerator is configured to irradiate microwaves from an antenna to the frozen items in the high-frequency heating chamber for microwave heating, it is difficult to uniformly heat the frozen items and defrost them to a desired state.

[0007] In addition, there is a commonly-available technology for high-frequency heating devices that use VHF radio frequencies to thaw frozen goods by providing a pair of electrodes and forming an electric field between the electrodes to thaw the frozen goods. However, such conventional high-frequency heating devices have the problem that the electric field generated between the pair of electrodes is not uniform, making it difficult to thaw the frozen goods uniformly.

[0008] Furthermore, in a configuration in which a high-frequency heating device is installed in a refrigerator to perform the thawing process, it is necessary to ensure a high level of safety by reliably securing not only the heating function of the heating device but also the functions of the refrigerator (cooling function, storage function) so that the high-frequency waves from the high-frequency heating device do not adversely affect preserved foods in other storage compartments or the user who handles them.

[0009] The present invention aims to provide a heating device that can uniformly heat objects to be heated and is highly reliable and safe, and to provide a refrigerator equipped with a storage space that can easily thaw stored frozen items to a high-quality state by incorporating the heating device. [Means for solving the problem]

[0010] A heating device according to one aspect of the present invention includes: A heating chamber having a heating space for accommodating an object to be heated; an oscillation electrode provided in one of the heating spaces and having an electrode surface on which an electric field concentration region is formed; a counter electrode provided in the other heating space and having an electrode surface facing the electrode surface of the oscillation electrode; and a high frequency electric field forming section for forming a high frequency electric field to be applied between the oscillation electrode and the counter electrode.

[0011] A refrigerator according to one aspect of the present invention includes: A heating chamber having a heating space for accommodating an object to be heated; an oscillation electrode provided in one of the heating spaces and having an electrode surface on which an electric field concentration region is formed; a counter electrode provided in the other heating space and having an electrode surface facing the electrode surface of the oscillation electrode; and a high-frequency electric field forming section for forming a high-frequency electric field to be applied between the oscillation electrode and the counter electrode. Effect of the Invention

[0012] According to the present invention, a heating device can be provided that can uniformize the electric field between electrodes in dielectric heating, and this heating device can be used to construct a highly safe refrigerator that has a storage compartment in which frozen goods can be easily thawed to a high-quality state, ensuring reliable cooling and storage functions. [Brief description of the drawings]

[0013] [Figure 1] FIG. 1 is a cross-sectional view showing a vertical section of a refrigerator according to a first embodiment of the present invention. [Diagram 2] FIG. 1 is a vertical cross-sectional view showing a freezing / thawing compartment in a refrigerator according to a first embodiment. [Diagram 3] FIG. 1 is a block diagram showing a configuration of a dielectric heating mechanism provided in a refrigerator according to a first embodiment. [Figure 4] FIG. 1 is a diagram showing an electrode holding area on the rear side of a freezing / thawing compartment in a refrigerator according to a first embodiment. [Diagram 5] FIG. 1 is a plan view showing an oscillation electrode and an inner surface member on the top surface side of a freezing / thawing compartment in a refrigerator according to a first embodiment; [Figure 6] FIG. 1 is a back view showing a counter electrode on a bottom surface side arranged opposite to an oscillation electrode in the refrigerator according to the first embodiment. [Figure 7] FIG. 11 is a plan view showing a modified example of the oscillation electrode in the refrigerator according to the first embodiment. [Figure 8] (a) is a cross-sectional view showing a schematic diagram of a dielectric heating configuration provided with a counter electrode having no electrode holes, and (b) is an electric field simulation diagram showing the results of a simulation performed on the dielectric heating configuration shown in (a). [Figure 9] (a) is a cross-sectional view showing a schematic diagram of a dielectric heating configuration provided with a counter electrode having an electrode hole, and (b) is an electric field simulation diagram showing the results of a simulation performed on the dielectric heating configuration shown in (a). [Figure 10] FIG. 11 is a vertical cross-sectional view showing a heating chamber of a heating device according to a second embodiment of the present invention. [Figure 11] FIG. 11 is a vertical cross-sectional view showing a state in which the heating device of the second embodiment is installed in a refrigerator. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0014] Hereinafter, a refrigerator having a freezing function will be described as an embodiment of a refrigerator having a heating device according to the present invention with reference to the accompanying drawings. The refrigerator according to the present invention is not limited to the configuration of the refrigerator described in the following embodiment, but can also be applied to a freezer having only a freezing function, and includes various refrigerators and freezers having the technical features described in the following embodiment. Therefore, in the present invention, a refrigerator is configured to include a refrigeration compartment and / or a freezing compartment.

[0015] In addition, the numerical values, shapes, configurations, steps, and order of steps shown in the following embodiments are merely examples and do not limit the present invention. Among the components in the following embodiments, components that are not described in an independent claim showing the highest concept are described as optional components. Note that in each embodiment, the same elements are given the same reference numerals and descriptions may be omitted. In addition, the drawings mainly show each component in a schematic manner to facilitate understanding.

[0016] First, various embodiments of the heating device of the present invention will be illustrated. The heating device according to the first aspect of the present invention comprises: A heating chamber having a heating space for accommodating an object to be heated; an oscillation electrode provided in one of the heating spaces and having an electrode surface on which an electric field concentration region is formed; a counter electrode provided in the other heating space and having an electrode surface facing the electrode surface of the oscillation electrode; and a high-frequency electric field forming unit for forming a high-frequency electric field to be applied between the oscillation electrode and the counter electrode. Therefore, the heating device of the first aspect can achieve uniformity of the electric field between the electrodes during dielectric heating.

[0017] A heating device according to a second aspect of the present invention may be configured such that electric field concentration regions are formed in a dispersed manner on the electrode surface of the oscillation electrode in the first aspect.

[0018] A heating device according to a third aspect of the present invention is the heating device according to the first or second aspect, wherein the electric field concentration region of the oscillation electrode may be constituted by an edge of an opening portion formed in the electrode surface.

[0019] A fourth aspect of the heating device according to the present invention is the heating device of the third aspect, wherein the opening portion formed in the electric field concentration region of the oscillation electrode may be configured as an electrode hole or an electrode notch.

[0020] A fifth aspect of the heating device according to the present invention may be such that, in any one of the first to fourth aspects, an electric field concentration area is formed on the electrode surface of the opposing electrode, and the opposing electrode is arranged so as not to face the electric field concentration area of ​​the oscillation electrode.

[0021] A sixth aspect of the heating device according to the present invention may be such that electric field concentration regions are formed in a dispersed manner on the electrode surface of the counter electrode in the fifth aspect.

[0022] A seventh aspect of the heating device according to the present invention is the heating device of the fifth or sixth aspect, wherein the electric field concentration region of the counter electrode may be constituted by an edge of an opening portion formed on the electrode surface.

[0023] An eighth aspect of the present invention provides the heating device of the seventh aspect, wherein the opening portion formed in the electric field concentration region of the counter electrode may be configured as an electrode hole or an electrode notch.

[0024] A heating device according to a ninth aspect of the present invention may be configured in any one of the first to eighth aspects such that the oscillation electrode and the counter electrode are not exposed to the heating space.

[0025] A heating device according to a tenth aspect of the present invention, in any one of the first to eighth aspects, may include an inner surface member that forms an inner surface of the heating chamber, and the inner surface member may be configured to cover the opposing electrode surfaces of the oscillation electrode and the counter electrode.

[0026] The heating device of an eleventh aspect according to the present invention, in any one of the first to tenth aspects, may be provided with an electromagnetic wave shield that suppresses radiation of electromagnetic waves from the oscillation electrode and the counter electrode to the outside of the device.

[0027] A heating device according to a twelfth aspect of the present invention is any one of the first to eleventh aspects, and may further include a door for inserting and removing an object to be heated into and from the heating space of the heating chamber, and the door may be provided with an electromagnetic wave shield.

[0028] A refrigerator according to a thirteenth aspect of the present invention is configured to include the heating device according to any one of the first to twelfth aspects. The refrigerator according to the thirteenth aspect configured in this manner includes a heating device that can homogenize the electric field between electrodes in dielectric heating, and therefore includes a storage chamber that can easily defrost frozen goods to a high-quality state, thereby providing a highly safe refrigerator with reliable cooling and storage functions.

[0029] (Embodiment 1) A first embodiment of a refrigerator equipped with a heating device according to the present invention will be described below with reference to the drawings. Fig. 1 is a diagram showing a vertical cross section of a refrigerator 10 according to the first embodiment. In Fig. 1, the left side is the front side of the refrigerator 10, and the right side is the rear side of the refrigerator 10. The refrigerator 10 is composed of an insulated box body formed of an outer box 1 mainly made of steel plate, an inner box 2 molded from a resin such as ABS, and an insulating material (for example, rigid urethane foam) 40 filled and foamed in the space between the outer box 1 and the inner box 2.

[0030] The insulated box of refrigerator 10 has a plurality of storage compartments, and an openable door is provided at the front opening of each storage compartment. Each storage compartment is sealed when the door is closed to prevent cold air from leaking. In refrigerator 10 of embodiment 1, the uppermost storage compartment is refrigerator compartment 3. Two storage compartments, an ice-making compartment 4 and a freezer / thawing compartment 5, are arranged side by side on both sides directly below refrigerator compartment 3. Furthermore, a freezer compartment 6 is provided directly below ice-making compartment 4 and freezer / thawing compartment 5, and a vegetable compartment 7 is provided at the bottom directly below freezer compartment 6. Each storage compartment in refrigerator 10 of embodiment 1 has the above-mentioned configuration, but this configuration is one example, and the layout and configuration of each storage compartment can be appropriately changed during design depending on specifications, etc.

[0031] The refrigerator compartment 3 is maintained at a temperature at which food and other preserved items are not frozen, specifically, in the temperature range of 1°C to 5°C, for example. The vegetable compartment 7 is maintained at a temperature equal to or slightly higher than that of the refrigerator compartment 3, specifically, in the temperature range of 2°C to 7°C, for example. The freezer compartment 6 is set to a freezing temperature range for frozen storage, specifically, in the temperature range of -22°C to -15°C, for example. The freezer / thaw compartment 5 is normally maintained at the same freezing temperature range as the freezer compartment 6, and a thawing process is performed to thaw the stored items (frozen items) in response to a thawing command from the user. The configuration of the freezer / thaw compartment 5 and details regarding the thawing process will be described later.

[0032] A machine room 8 is provided in the upper part of the refrigerator 10. The machine room 8 accommodates components constituting the refrigeration cycle, such as a compressor 9 and a dryer that removes moisture in the refrigeration cycle. The location of the machine room 8 is not limited to the upper part of the refrigerator 10, but is appropriately determined depending on the location of the refrigeration cycle, and the machine room 8 may be provided in another area, such as the lower part of the refrigerator 10.

[0033] A cooling compartment 11 is provided behind the freezer compartment 6 and the vegetable compartment 7 in the lower region of the refrigerator 10. The cooling compartment 11 is provided with a cooler 12, which is a component of a refrigeration cycle that generates cold air, and a cooling fan 13 that blows the cold air generated by the cooler 12 to each storage compartment (3, 4, 5, 6, 7). The cold air generated by the cooler 12 flows through an air duct 18 connected to each storage compartment by the cooling fan 13 and is supplied to each storage compartment. A damper 19 is provided in the air duct 18 connected to each storage compartment, and each storage compartment is maintained at a predetermined temperature range by controlling the rotation speed of the compressor 9 and the cooling fan 13 and opening and closing the damper 19. A defrost heater 14 is provided at the bottom of the cooling compartment 11 to remove frost and ice that adheres to the cooler 12 and its surroundings. A drain pan 15, a drain tube 16, and an evaporation dish 17 are provided below the defrost heater 14, and are configured to evaporate moisture generated during defrosting or the like.

[0034] The refrigerator 10 of the first embodiment is provided with an operation unit 47 (see FIG. 3 described later). A user can use the operation unit 47 to issue various commands to the refrigerator 10 (for example, temperature setting for each storage compartment, a command to rapidly cool, a command to defrost, a command to stop making ice, etc.). The operation unit 47 also has a display unit that notifies the occurrence of an abnormality, etc. The refrigerator 10 may be configured to include a wireless communication unit and connect to a wireless LAN network, so that various commands can be input from a user's external terminal. The refrigerator 10 may also be configured to include a voice recognition unit and so that a user can input commands by voice.

[0035] 2 is a vertical cross-sectional view showing the freezing / thawing compartment 5 in the refrigerator 10 of the first embodiment. The freezing / thawing compartment 5 is a freezer that keeps stored items such as food stored in the freezing / thawing compartment 5 at a freezing temperature range, and also serves as a thawing compartment that performs a thawing process by dielectric heating when a thawing command for the stored items is input to the refrigerator 10. In this way, the refrigerator 10 of the first embodiment is configured to include a heating device having a dielectric heating function so that the thawing process by dielectric heating can be performed in the freezing / thawing compartment 5. In other words, the freezing / thawing compartment 5 corresponds to the heating chamber of the heating device.

[0036] In order to maintain the freezing / thawing chamber 5 at the same freezing temperature range as the freezing chamber 6, the cold air generated in the cooler 12 flows through air passages 18 provided on the back and top sides of the freezing / thawing chamber 5 and is introduced into the freezing / thawing chamber 5 from a plurality of cold air introduction holes 20 provided on the top surface of the freezing / thawing chamber 5. A damper 19 is provided in the air passage 18 leading from the cooling chamber 11 to the freezing / thawing chamber 5, and the freezing / thawing chamber 5 is maintained at a specified freezing temperature range by controlling the opening and closing of the damper 19, and the stored items contained therein are frozen and preserved.

[0037] A cold air exhaust hole 21 is formed on the back surface of the freezing / thawing compartment 5. The cold air that is introduced into the freezing / thawing compartment 5 and cools the inside of the freezing / thawing compartment 5 returns from the cold air exhaust hole 21 to the cooling compartment 11 through the return air passage 34, and is re-cooled by the cooler 12. That is, the refrigerator 10 of the first embodiment is configured so that the cold air formed by the cooler 12 is circulated.

[0038] The top, back, both sides, and bottom constituting the inner surface of the storage space in the freezing / thawing chamber 5 are formed of an inner surface member 32 made of a resin material molded from an electrically insulating material. A door 29 is provided at the front opening of the freezing / thawing chamber 5, and the storage space of the freezing / thawing chamber 5 is sealed when the door 29 is closed. In the freezing / thawing chamber 5 of the first embodiment, a storage case 31 with an open top is provided on the back side of the door 29, and the storage case 31 moves back and forth simultaneously when the door 29 is opened and closed in the front-rear direction. The opening of the door 29 in the front direction makes it easy to put food and other preserved items into and take them out of the storage case 31.

[0039] Next, a dielectric heating mechanism in the heating device that performs dielectric heating to perform a thawing process on the stored object frozen in the freezing / thawing chamber 5 will be described.

[0040] FIG. 3 is a block diagram showing a configuration of a dielectric heating mechanism provided in refrigerator 10 of embodiment 1. The dielectric heating mechanism in embodiment 1 includes an oscillation circuit 22 that receives power from power supply unit 48 to form a predetermined high-frequency signal, a matching circuit 23, an oscillation electrode 24, a counter electrode 25, and a control unit 50. Oscillator circuit 22, which is configured using semiconductor elements, is miniaturized and provided in machine room 8 of refrigerator 10. Oscillator circuit 22 is electrically connected to matching circuit 23 by a coaxial cable. Matching circuit 23 is disposed in electrode holding area 30 (see FIG. 2), which is a space on the back side of freezing / thawing compartment 5. Oscillator circuit 22 and matching circuit 23 serve as a high-frequency electric field forming unit for forming a high-frequency electric field to be applied between oscillation electrode 24 and counter electrode 25.

[0041] The oscillation electrode 24 is a planar electrode disposed on the top surface side of the freezing / thawing chamber 5. The counter electrode 25 is a planar electrode disposed on the bottom surface side of the freezing / thawing chamber 5. The oscillation electrode 24 and the counter electrode 25 are disposed opposite each other across the storage space (thawing space) of the freezing / thawing chamber 5, and a distance defining portion (33) described in the "electrode holding mechanism" below is provided to set the opposing distance to a predetermined distance (first distance) that has been set in advance. As a result, in the dielectric heating mechanism in the first embodiment, the oscillation electrode 24 and the counter electrode 25 are disposed approximately parallel to each other. In the present invention, "approximately parallel" refers to an essentially parallel state, but also indicates that it includes errors due to variations in processing accuracy and the like.

[0042] The oscillation electrode 24 is provided on one side of the storage space, and the counter electrode 25 is provided on the other side of the storage space across the storage space. The matching circuit 23 on the back side, the oscillation electrode 24 on the top side, and the counter electrode 25 on the bottom side, which constitute the dielectric heating mechanism, are covered with an inner surface member 32, which is configured to reliably prevent stored items from being burned due to contact with them.

[0043] In the configuration of embodiment 1, an oscillating electrode 24 is provided on the top surface forming the storage space of the freezing / thawing chamber 5, and a counter electrode 25 is provided on the bottom surface of the storage space of the freezing / thawing chamber 5. However, the present invention is not limited to this configuration, and it is sufficient that the oscillating electrode 24 and the counter electrode 25 are configured to face each other across the storage space (thawing space), and the same effect can be achieved even if they are arranged upside down or facing each other in the left-right direction.

[0044] As shown in FIG. 2, the freezing / thawing compartment 5 has a configuration in which cold air from the cooler 12 passes through the air passage 18 and is introduced from the top side of the freezing / thawing compartment 5. At the top side of the freezing / thawing compartment 5, an oscillation electrode 24 is disposed on the lower surface of the air passage 18, and cold air from the cooling compartment 11 flows over the oscillation electrode 24. In the refrigerator 10 of the first embodiment, an insulated box is formed by the outer box 1, the inner box 2, and the insulating material 40 filled and foamed between them, and the space in which the storage compartment is formed in this insulated box does not have high dimensional accuracy. In the space in which the freezing / thawing compartment 5 is formed, an area that becomes the air passage 18 is formed on the top side, and this area that becomes the air passage 18 becomes a space that can absorb dimensional variations in the insulated box. The configuration in which the cold air that has passed through the air passage 18 passes through a plurality of electrode holes 41 formed in the oscillation electrode 24 and is introduced into the freezing / thawing compartment 5 from the cold air introduction hole 20 of the inner surface member 32 on the top side will be described later.

[0045] The oscillator circuit 22 outputs a high-frequency voltage in the VHF band (40.68 MHz in the first embodiment). When the oscillator circuit 22 outputs the high-frequency voltage, an electric field is formed between the oscillator electrode 24 to which the oscillator circuit 22 is connected and the counter electrode 25, and the stored object, which is a dielectric material arranged in the storage space between the oscillator electrode 24 and the counter electrode 25 in the freezing / thawing chamber 5, is dielectrically heated.

[0046] The matching circuit 23 adjusts the load impedance formed by the oscillation electrode 24, the counter electrode 25, and the stored object accommodated in the freezing / thawing chamber 5 so that it matches the output impedance of the oscillation circuit 22. The matching circuit 23 minimizes the reflected wave of the output electromagnetic wave by matching the impedance. The dielectric heating mechanism in the first embodiment is provided with a reflected wave detection unit 51 that detects the reflected wave returning from the oscillation electrode 24 to the oscillation circuit 22. Therefore, the oscillation circuit 22 is electrically connected to the oscillation electrode 24 via the reflected wave detection unit 51 and the matching circuit 23. The control unit 50 calculates the ratio (reflectance) of the reflected wave output to the electromagnetic wave output based on the electromagnetic wave output output from the oscillation circuit 22 after impedance matching in the matching circuit 23 and the reflected wave detected by the reflected wave detection unit 51, and performs various controls based on the calculation results as described below.

[0047] As shown in the block diagram of Fig. 3, in the dielectric heating mechanism, a control unit 50 drives and controls the oscillation circuit 22 and the matching circuit 23 based on signals from an operation unit 47 for performing setting operations by the user and a temperature sensor 49 for detecting the temperature inside the chamber. The control unit 50 is composed of a CPU, and executes control programs stored in a memory such as a ROM to perform various controls.

[0048] In addition, since it is desirable for the length of the positive electrode wiring connecting the oscillator circuit 22, the matching circuit 23, and the oscillator electrode 24 to be short, the high-frequency electric field forming portion of the oscillator circuit 22 and the matching circuit 23 may be configured to be disposed in the electrode holding area 30 on the rear side of the freezing / thawing chamber 5.

[0049] [Electrode holding mechanism] The dielectric heating mechanism in the first embodiment configured as described above has a configuration in which the flat-plate oscillating electrode 24 and the counter electrode 25 face each other substantially parallel to each other, thereby achieving a uniform electric field in the thawing space, which is the storage space of the freezing / thawing chamber 5. In order to thus dispose the oscillating electrode 24 and the counter electrode 25 substantially parallel to each other with a predetermined interval (first interval) therebetween, the dielectric heating mechanism in the first embodiment has an electrode holding mechanism, which will be described below.

[0050] FIG. 4 is a diagram showing the electrode holding area 30 on the back side of the freezing / thawing chamber 5 in the first embodiment, and shows an electrode holding mechanism in the electrode holding area 30. FIG. 4 is a diagram showing the electrode holding area 30 as seen from the back side, with the oscillation electrode 24 disposed on the upper side (top side) and the counter electrode 25 disposed on the lower side (bottom side). A positive electrode terminal 24a protrudes from the center of the back side end of the flat plate-like oscillation electrode 24, and support members 24b, 24b protrude from both sides of the positive electrode terminal 24a. The positive electrode terminal 24a and the support member 24b protrude downward (bottom side) from the back side end of the flat plate-like oscillation electrode 24 at a right angle. Similarly, a negative electrode terminal 25a protrudes from the center of the back side end of the flat plate-like counter electrode 25, and support members 25b, 25b protrude from both sides of the negative electrode terminal 25a. The negative electrode terminal 25a and the support member 25b are bent at a right angle and protrude upward (toward the top surface) from the rear end of the flat plate-shaped counter electrode 25. That is, the protruding ends of the positive electrode terminal 24a of the oscillation electrode 24 and the support member 24b face the protruding ends of the negative electrode terminal 25a of the counter electrode 25 and the support member 25b, respectively.

[0051] As described above, the protruding direction of each of the support members 24b, 24b of the oscillation electrode 24 faces the protruding direction of each of the support members 25b, 25b of the counter electrode 25, and each of the support members 24b, 24b is linearly joined to the opposing support members 25b, 25b via the interval defining portion 33. The interval defining portion 33 is a planar member, and is formed of an electrically insulating member that is not substantially dielectrically heated. As shown in FIG. 4, the interval defining portion 33 has an H-shape when viewed from the rear side, and the support members (24b, 25b) are connected to the four upper and lower ends of the H-shape, and the matching circuit 23 is fixed to the center portion of the H-shape. Therefore, the oscillation electrode 24 and the counter electrode 25 are fixed to both the upper and lower ends of the interval defining portion 33, the matching circuit 23 is fixed to the center portion of the interval defining portion 33, and the oscillation electrode 24, the counter electrode 25, and the matching circuit 23 are reliably held by the interval defining portion 33. In this way, the spacing defining portion 33 is configured to reliably hold the oscillation electrode 24 and the counter electrode 25, which are essentially planar plate-like members, at a predetermined distance (first interval). Since the matching circuit 23 is fixed to the center of the H-shape of the spacing defining portion 33, the spacing defining portion 33 has high rigidity and is configured to be able to cantilever-hold the oscillation electrode 24 and the counter electrode 25 at a predetermined opposing interval (first interval). Also, the spacing defining portion 33 may be configured to be provided with a high-frequency electric field generating portion for the oscillation circuit 22 and the matching circuit 23.

[0052] The positive terminal 24a of the oscillation electrode 24 and the negative terminal 25a of the counter electrode 25 are connected to the positive and negative connection terminals of the matching circuit 23. The connection between the positive terminal 24a and the negative terminal 25a and the connection terminals of the matching circuit 23 is a surface-contact connection having a predetermined contact area so as to ensure reliability even when a large current flows. In the first embodiment, in order to ensure a reliable surface-contact connection, the flat terminals are connected to each other by screws. Note that the connection between the terminals may be any connection means that provides a reliable surface-contact connection, and is not limited to a screw connection.

[0053] In the first embodiment, the terminal width w (see FIG. 4) of the positive terminal 24a protruding from the rear end of the oscillation electrode 24 is formed to be much narrower than the electrode width W (see FIG. 4) of the rear end of the oscillation electrode 24 (w<<W). This is to make it difficult for heat generated in the matching circuit 23 to be conducted to the oscillation electrode 24, and to suppress the thermal conduction between the matching circuit 23 and the oscillation electrode 24, thereby suppressing the occurrence of condensation in the matching circuit 23 when the oscillation electrode 24 is cooled. In addition, the terminal width of the negative terminal 25a of the counter electrode 25 is also formed to be much narrower than the electrode width of the rear end of the counter electrode 25 from which the negative terminal 25a protrudes, similar to the terminal width of the positive terminal 24a. By narrowing the terminal width of the negative terminal 25a in this way, the thermal conduction between the counter electrode 25 and the matching circuit 23 is suppressed.

[0054] 2 and 4, the cold air that has frozen the stored items in the freezing / thawing chamber 5 is configured to pass through the electrode holding area 30 from the cold air exhaust hole 21 via the return air duct 34 and return to the cooling chamber 11. Because the return air duct 34 is configured to pass through the electrode holding area 30 in this manner, the cold air from the freezing / thawing chamber 5 is not discharged at the electrode holding area 30, and condensation is prevented in the electrode holding area 30 including the matching circuit 23.

[0055] In addition, in a configuration in which the oscillation circuit 22 is disposed in the electrode holding area 30, a cooling configuration in which a heat sink, which is a heat dissipation member in the oscillation circuit 22, is brought into contact with the return air passage 34 for cooling may be used.

[0056] As described above, an electrode holding mechanism is provided on the rear side of the freezing / thawing chamber 5, so that the flat plate-shaped oscillation electrode 24 and the counter electrode 25 face each other substantially parallel to each other. In the configuration of the first embodiment, an electrode holding mechanism is also provided on the front side of the freezing / thawing chamber 5 to further ensure that the oscillation electrode 24 and the counter electrode 25 face each other substantially parallel to each other.

[0057] As described above, the insulated box of refrigerator 10 is composed of outer box 1 made of steel plate, inner box 2 molded from resin, and insulating material (e.g., rigid urethane foam) 40 filled and foamed in the space between outer box 1 and inner box 2. In addition, cross rail 35, which is a frame for defining the edge of the front opening of each storage compartment, is provided in the insulated box of refrigerator 10. Cross rail 35 of the frame is joined to a predetermined position of outer box 1 and is positioned with high precision relative to outer box 1. Therefore, the position of cross rail 35 with respect to outer box 1 is not affected by the filled and foamed insulating material 40, and is positioned with high precision.

[0058] 2, a cross rail 35 is provided on the edge of the front side of the freezing / thawing compartment 5, and a front opening of the freezing / thawing compartment 5 is defined by this cross rail 35. This front opening is opened and closed by a door 29 of the freezing / thawing compartment 5. A gasket 36 is provided between the door 29 and the cross rail 35 to prevent leakage of cool air when the door is closed.

[0059] The electrode holding mechanism on the front side of the freezing / thawing chamber 5 utilizes a cross rail 35 which is a frame that precisely defines the front opening of the freezing / thawing chamber 5. First holding claw 37 and second holding claw 38 which are holding members are integrally formed at a predetermined interval on the approximately parallel frame members above and below the cross rail 35. The first holding claw 37 and second holding claw 38 which are holding members may be configured to be joined to the cross rail 35 which is the frame.

[0060] The first holding claw 37, which is a holding member, is configured to engage the front end of the oscillation electrode 24 so as to sandwich it, and determines the position of the front end of the oscillation electrode 24. The second holding claw 38, which is a holding member, is configured to support the front end of the counter electrode 25, and determines the position of the front end of the counter electrode 25. The first holding claw 37 and the second holding claw 38 hold the front end of each of the oscillation electrode 24 and the counter electrode 25 with a predetermined interval (first interval) between them. The first holding claw 37 and the second holding claw 38 also hold the oscillation electrode 24 and the counter electrode 25 in an electrically insulated state.

[0061] Therefore, in refrigerator 10 of embodiment 1, since the dielectric heating mechanism of freezing / thawing compartment 5 is provided with electrode holding mechanisms on both the back side and the front side, oscillation electrode 24 and counter electrode 25 can be arranged with a highly accurate opposing distance, and can also be arranged reliably approximately parallel with a predetermined distance (first distance). As a result, the dielectric heating mechanism of freezing / thawing compartment 5 is configured to prevent bias of the high-frequency electric field on the electrode surface and to homogenize the high-frequency electric field, enabling uniform thawing of stored items (frozen goods).

[0062] [Electromagnetic wave shielding mechanism] As described above, in freezing / thawing compartment 5, a dielectric object is placed in the atmosphere of a high-frequency electric field between oscillating electrode 24 and counter electrode 25 and dielectrically heated, and therefore, electromagnetic waves can be emitted in freezing / thawing compartment 5. In order to prevent these electromagnetic waves from leaking outside refrigerator 10, refrigerator 10 of the first embodiment is provided with an electromagnetic wave shielding mechanism surrounding freezing / thawing compartment 5.

[0063] As shown in FIG. 2, a top-side electromagnetic wave shield 26 is disposed above the air passage 18 on the top side of the freezing / thawing compartment 5. The top-side electromagnetic wave shield 26 is disposed on the top surface of the heat insulating material 40 constituting the bottom side of the refrigeration compartment 3 directly above the freezing / thawing compartment 5, and is disposed so as to cover the top side of the freezing / thawing compartment 5. The top-side electromagnetic wave shield 26 has a plurality of openings, and is configured so as to reduce the substantial opposing area with respect to the oscillation electrode 24. The top-side electromagnetic wave shield 26 configured in this manner is configured to suppress the generation of unnecessary electric fields between the oscillation electrode 24. The top-side electromagnetic wave shield 26 may have a mesh structure having a plurality of openings. The top-side electromagnetic wave shield 26 may be disposed inside the refrigeration compartment 3 located directly above the freezing / thawing compartment 5, but the refrigeration compartment 3 often has a partial compartment or a chilled compartment, and the top surface of the partial compartment or the chilled compartment may be used as the electromagnetic wave shield.

[0064] A rear electromagnetic shield 27 is provided so as to cover the electrode holding area 30 having the matching circuit 23 and the like provided on the rear side of the freezing / thawing chamber 5. Providing the rear electromagnetic shield 27 in this manner prevents the electric field generated between the oscillation electrode 24 and the counter electrode 25 and the high-frequency noise generated from the matching circuit 23 from affecting the operation (control) of the electrical components of the cooling fan 13 and the damper 19. An electromagnetic shield (not shown) is also provided on the side of the freezing / thawing chamber 5.

[0065] Next, a description will be given of the door-side electromagnetic shield 39 provided on the door 29 that opens and closes the front opening of the freezing / thawing compartment 5. Since the door 29 is configured to open and close relative to the body of the refrigerator 10, if the electromagnetic shield provided on the door 29 is connected to the grounded part of the body of the refrigerator 10 by a wired path, the wired path will repeatedly expand and contract as the door 29 is opened and closed, and metal fatigue will accumulate in the wired path. Since such a connection configuration can cause the wired path to break, it is not preferable to connect the electromagnetic shield 39 provided on the door 29 to the grounded part of the body of the refrigerator 10 by a wired path.

[0066] In general, in order to prevent electromagnetic wave leakage, it is necessary to make the distance between the door-side electromagnetic shield 39 and the cross rail 35, which serves as the electromagnetic shield on the main body side, shorter than 1 / 4 of the wavelength λ of the electromagnetic wave when the door 29 is closed. In the first embodiment, the distance is further reduced to obtain the effect of contact without providing a wired path. For example, the distance between the door-side electromagnetic shield 39 and the cross rail 35 when the door 29 is closed is set to 30 mm or less. Since the cross rail 35 connected to the outer box 1 is grounded, by bringing the door-side electromagnetic shield 39 close to the cross rail 35 when the door 29 is closed, an effect equivalent to grounding by a wired path can be obtained. In addition, by making the end of the door-side electromagnetic shield 39 bent toward the main body side of the refrigerator 10, the door-side electromagnetic shield 39 can be easily brought close to the cross rail 35.

[0067] In refrigerator 10 according to the first embodiment, outer box 1 is made of a steel plate, and the steel plate itself functions as an electromagnetic wave shield. This reliably prevents electromagnetic waves from inside refrigerator 10 from leaking to the outside of refrigerator 10.

[0068] [Configuration of the oscillation electrode and the counter electrode] When the user opens the door 29, high humidity air flows from the outside into the freezing / thawing compartment 5, which is maintained in the freezing temperature range, and the inside of the freezing / thawing compartment 5 becomes in a state where condensation is likely to occur. If condensation occurs on the surfaces of the oscillation electrode 24 and the counter electrode 25, the electric field formation between the electrodes becomes unstable, and a state where desired dielectric heating is not performed may occur. In order to prevent such a state from occurring, in the refrigerator 10 of the first embodiment, the opposing electrode surfaces of the oscillation electrode 24 and the counter electrode 25 are covered with an inner surface member 32, and cold air is introduced into the freezing / thawing compartment 5 through a plurality of cold air introduction holes 20 formed in the oscillation electrode 24. The cold air introduced into the freezing / thawing compartment 5 is cold air sent from the cooling compartment 11 through the air passage 18 by the cooling fan 13, and the cold air at the time of introduction is in a relatively low humidity state. Therefore, even if the door 29 is opened or closed and high humidity air flows in from the outside, low humidity cold air is blown into the freezing / thawing chamber 5 from the multiple cold air inlet holes 20 formed over the entire top side, and the air inside the freezing / thawing chamber 5 is exhausted from the cold air exhaust holes 21 on the back side, so that the inside of the freezing / thawing chamber 5 is less likely to develop condensation.

[0069] 5 is a plan view of the oscillation electrode 24 and the inner surface member 32 on the top surface side of the freezing / thawing chamber 5, as viewed from above. As shown in FIG. 5, a plurality of electrode holes 41 are formed in the oscillation electrode 24, and the plurality of electrode holes 41 are distributed over the entire surface of the electrode surface of the oscillation electrode 24. The electrode holes 41 are arranged approximately uniformly at equal intervals on the electrode surface of the oscillation electrode 24. The electrode holes 41 of the oscillation electrode 24 are provided in correspondence with the positions of the cold air introduction holes 20 formed in the inner surface member 32 covering the lower surface of the oscillation electrode 24. The hole diameter D of the electrode hole 41 is formed to be larger than the hole diameter d of the cold air introduction hole 20 of the inner surface member 32 (D>d).

[0070] Since the electrode holes 41 are formed at equal intervals and approximately uniformly on the electrode surface of the oscillation electrode 24, the regions where a strong electric field is formed are uniformly distributed on the electrode surface of the oscillation electrode 24, and the stored items can be uniformly dielectrically heated. That is, the edges of the openings of the electrode holes 41 become the electric field concentration regions. Note that the shapes and arrangements of the cold air introduction holes 20 and the electrode holes 41 shown in Fig. 5 are merely examples, and the shapes and arrangements of the cold air introduction holes 20 and the electrode holes 41 are appropriately designed in consideration of efficiency and manufacturing costs according to the specifications and configuration of the refrigerator.

[0071] FIG. 6 is a back view showing the bottom side counter electrode 25 arranged opposite the oscillation electrode 24. FIG. 6 is a view of the counter electrode 25 seen from below, and an inner surface member 32 that becomes the bottom surface of the freezing / thawing chamber 5 is arranged on the counter electrode 25. As shown in FIG. 6, a plurality of electrode holes 42 are formed at equal intervals and approximately uniformly on the electrode surface of the counter electrode 25, similar to the oscillation electrode 24. However, in the configuration of the first embodiment, the electrode holes 42 of the counter electrode 25 are formed at positions that do not face the electrode holes 41 of the oscillation electrode 24. That is, the position of the central axis extending in the vertical direction of the electrode holes 42 of the counter electrode 25 is shifted from the position of the central axis extending in the vertical direction of the electrode holes 41 of the oscillation electrode 24, and the electrode holes 42 of the counter electrode 25 and the electrode holes 41 of the oscillation electrode 24 are shifted in position in the vertical direction (opposing direction).

[0072] In the configuration of the first embodiment, the shape and arrangement of the electrode holes 41 of the oscillation electrode 24 are described as being arranged substantially uniformly at equal intervals, but the present invention is not limited to such a configuration. For example, the oscillation electrode 24 may have at least one opening, and the edge of the opening becomes an electric field concentration region in which the electric field is concentrated on the electrode surface of the oscillation electrode 24. That is, the present invention may be configured so that the electric field concentration region is dispersed on the electrode surface of the oscillation electrode 24. In addition, in the first embodiment, the configuration in which a plurality of electrode holes 42 are provided on the electrode surface of the counter electrode 25 is described, but the present invention is not limited to the configuration in which a plurality of electrode holes 42 are provided on the counter electrode 25, and may be an opening formed so that a desired electric field is formed between the electrode and the oscillation electrode 24.

[0073] FIG. 7 is a plan view showing an example of a modified example of the oscillation electrode 24 in the first embodiment. The modified example shown in FIG. 7(a) shows an example in which one opening portion is formed as the electrode hole 41A in the oscillation electrode 24. In the first embodiment, the opening portion formed in the oscillation electrode 24 is the electrode opening, and this electrode opening includes the electrode holes (41, 41A). The electrode opening 41A shown in FIG. 7(a) includes a circular opening 41a, an arc-shaped opening 41b, and a communication opening 41c that communicates the respective openings (41a, 41b). By forming the electrode opening 41A in such a shape, it is possible to disperse the region in which the electric field becomes strong on the electrode surface of the oscillation electrode 24. Also, the modified example shown in FIG. 7(b) shows a modified example of the electrode opening (41B) in the oscillation electrode 24, and is an example in which an electrode notch portion 41B in which a notch portion is formed in the oscillation electrode 24B is formed. 7(b), by forming the electrode cutout portion 41B as the electrode opening, the region where the electric field becomes strong is dispersed on the electrode surface of the oscillation electrode 24. The cold air introduction hole 20 formed in the inner surface member 32 covering the lower surface of the oscillation electrode 24 is formed at a position corresponding to the electrode opening (41, 41A, 41B) of the oscillation electrode 24, and is configured so that the cold air from the air passage 18 is smoothly introduced into the freezing / thawing chamber 5.

[0074] As described above, in the top surface side of the freezing / thawing chamber 5 in the first embodiment, cold air is introduced into the inside of the freezing / thawing chamber 5 through the electrode openings (41, 41A, 41B) which are the openings of the oscillation electrode 24 constituting the lower surface of the air passage 18. Therefore, in the freezing / thawing chamber 5, cold air is blown from the cold air introduction holes 20 formed on the top surface side, and a uniform and rapid freezing process can be performed in the freezing / thawing chamber 5. In addition, since the electrode surface of the oscillation electrode 24 is formed so that the electric field concentration area is dispersed, uniform dielectric heating can be performed on the stored items, and good thawing can be performed.

[0075] 5 and 6, the electrode hole 41 of the oscillation electrode 24 and the electrode hole 42 of the counter electrode 25 are formed so that their central axes extending in the vertical direction (opposing direction) do not coincide with each other, thereby dispersing the area where the electric field is concentrated between the oscillation electrode 24 and the counter electrode 25, and homogenizing the electric field in the storage space where the oscillation electrode 24 and the counter electrode 25 face each other. As a result, the stored items placed in the storage space of the freezing / thawing chamber 5 can be dielectrically heated more uniformly.

[0076] The inventors performed a simulation of electric field generation between electrodes using a freezing / thawing chamber 5 having the electrode configuration of embodiment 1 and, as a comparative example, a freezing / thawing chamber 5X having an electrode configuration provided with a counter electrode 25X that does not have an electrode hole.

[0077] FIG. 8(a) is a cross-sectional view showing a schematic electrode configuration in which a counter electrode 25X having no electrode hole is provided, and is a diagram showing a freezing / thawing chamber 5X cut in the left-right direction. FIG. 8(b) shows the results of simulating the electric field strength when an electric field is applied to the electrodes of the electrode configuration shown in FIG. 8(a). In FIG. 8(b), the dark parts are areas where the electric field is concentrated. As is clear from this electric field simulation diagram, the electric field is concentrated at the outer edge parts of the electrodes, and especially at the corner parts.

[0078] FIG. 9(a) is a cross-sectional view showing a schematic diagram of the electrode configuration of the freezing / thawing chamber 5 having the configuration of the first embodiment, and shows the freezing / thawing chamber 5 cut in the left-right direction. FIG. 9(b) shows the results of simulating the electric field strength when an electric field is applied to the electrodes of the electrode configuration shown in FIG. 9(a). In FIG. 9(b), as in FIG. 8(b), the darker parts are areas where the electric field is concentrated. As is clear from this electric field simulation diagram, compared to the electric field simulation diagram of FIG. 8(b), the dielectric heating configuration of FIG. 9(a) has a reduced electric field concentration over the entire electrode, and it can be understood that the electric field is made uniform.

[0079] 9(b), the electrode holes 41 of the oscillation electrode 24 and the electrode holes 42 of the counter electrode 25 are arranged so that their central axes extending in the vertical direction (opposing direction) do not coincide with each other, thereby alleviating electric field concentration in the entire electrode. In the electrode configuration in which the electrode holes 41 of the oscillation electrode 24 and the electrode holes 42 of the counter electrode 25 are arranged so that their central axes extending in the vertical direction (opposing direction) coincide with each other, electric field concentration is alleviated compared to the configuration in which the counter electrode 25X having no electrode hole shown in FIG. 8 is provided, and electric field concentration is particularly alleviated at the corners.

[0080] In the freezing / thawing compartment 5 of the refrigerator 10 according to the first embodiment, as shown in FIG. 2, the storage case 31 is fixed to the rear side of the door 29. The storage case 31 moves back and forth inside the freezing / thawing compartment 5 as the door 29 opens and closes. In the configuration according to the first embodiment, rails 52 are provided on both sides of the freezing / thawing compartment 5 so that the storage case 31 can move smoothly inside the freezing / thawing compartment 5 (see FIG. 9). Furthermore, frames 53 that slide on the rails 52 are provided on both sides of the outside of the storage case 31. The sliding members of the rails 52 and the frames 53 are provided at positions outside the dielectric heating area, which is the area where the oscillation electrode 24 and the counter electrode 25 of the freezing / thawing compartment 5 face each other, so as not to be dielectrically heated.

[0081] As described above, refrigerator 10 of embodiment 1 is provided with a heating device in which an electric field concentration region is formed on the electrode surface of oscillation electrode 24, and is configured to be able to apply a high-frequency electric field in a desired state between oscillation electrode 24 and counter electrode 25. As a result, refrigerator 10 of embodiment 1 has the excellent effect of being able to thaw frozen goods to a desired high-quality state in a short time when thawing process is performed by performing dielectric heating in freezing / thawing compartment 5, and is configured to be able to be miniaturized as a refrigerator with excellent thawing function by using a heating device of a dielectric heating mechanism composed of semiconductor elements.

[0082] In the refrigerator 10 according to the first embodiment, the freezing / thawing compartment 5 has both a freezing function and a thawing function. However, the refrigerator 10 may have a thawing compartment only having a thawing function.

[0083] (Embodiment 2) Hereinafter, a refrigerator according to the second embodiment of the present invention will be described with reference to the accompanying drawings. The refrigerator according to the second embodiment is configured to incorporate a heating device. The heating device incorporated in the refrigerator according to the second embodiment is configured by forming the freezing / thawing chamber 5 in the refrigerator 10 according to the first embodiment using a high-frequency heating device. In the heating device according to the second embodiment, it is possible to use the same configuration as the electrode structure, electrode holding mechanism, and electromagnetic shielding mechanism in the first embodiment, but the present invention can achieve the same effect even if the configuration described in the second embodiment is used. The other configurations in the refrigerator in which the heating device according to the second embodiment is incorporated are the same as those in the refrigerator 10 according to the first embodiment. In the description of the second embodiment, elements having the same action, configuration, and function as those in the first embodiment are given the same reference numerals, and descriptions may be omitted to avoid duplication. In the heating device incorporated in the refrigerator according to the second embodiment, the dielectric heating mechanism capable of uniformly heating the object to be heated placed in the heating space can be configured to be used alone as a heating device without being incorporated in the refrigerator.

[0084] Fig. 10 is a vertical cross-sectional view showing a high-frequency heating device which is a heating device of embodiment 2. The high-frequency heating device shown in Fig. 10 is shown in a state where it is incorporated into refrigerator 10, and includes heating chamber 55 which functions as a freezing / thawing chamber. Heating chamber 55 has a heating space for accommodating an object to be heated, and dielectrically heats the object to be heated accommodated in the heating space (storage space).

[0085] In heating chamber 55, the top, back, both sides, and bottom constituting the inner surface of the heating space are formed of inner surface member 32 made of a resin material molded from an electrically insulating material. A door 29 is provided at the front opening of heating chamber 55, and the heating space of heating chamber 55 is sealed when door 29 is closed. In heating chamber 55 of embodiment 2, a storage case 31 with an open top is provided on the back side of door 29, and storage case 31 moves back and forth at the same time when door 29 is opened and closed in the front-rear direction. This configuration is the same as that of freezing / thawing chamber 5 in embodiment 1.

[0086] The dielectric heating mechanism of the heating device in the second embodiment includes an oscillation circuit 22, a matching circuit 23, an oscillation electrode 24, a counter electrode 25, and a control unit (not shown). In the heating device in the second embodiment, the oscillation circuit 22 is disposed on the rear side of the heating chamber 55 together with the matching circuit 23. The heating chamber 55 is capable of dielectrically heating an object to be heated contained in the heating space, and like the freezing / thawing chamber 5 in the first embodiment, it is a freezer that holds stored objects such as food contained in the heating chamber 55 at a freezing temperature range, and also serves as a thawing chamber that performs a thawing process by dielectric heating when a thawing command for the stored object is input in the refrigerator 10.

[0087] The oscillation circuit 22 and the matching circuit 23 are a high-frequency electric field forming section for forming a high-frequency electric field to be applied between the oscillation electrode 24 and the counter electrode 25. The oscillation electrode 24 is a planar electrode disposed on the top surface side of the heating chamber 55. The counter electrode 25 is a planar electrode disposed on the bottom surface side of the heating chamber 55. The oscillation electrode 24 and the counter electrode 25 are disposed opposite each other across the heating space (storage space / thawing space) of the heating chamber 55. In the dielectric heating mechanism in the second embodiment, the oscillation electrode 24 and the counter electrode 25 are disposed approximately parallel to each other, the oscillation electrode 24 is disposed on one side of the heating space, and the counter electrode 25 is disposed on the other side of the heating space across the heating space. The matching circuit 23 on the back surface side, the oscillation electrode 24 on the top surface side, and the counter electrode 25 on the bottom surface side, which constitute the dielectric heating mechanism, are covered by the inner surface member 32, and are configured to reliably prevent the stored items from being burned due to contact.

[0088] In the configuration of embodiment 2, as in the configuration of embodiment 1, an oscillation electrode 24 is provided on the top surface forming the heating space of the heating chamber 55, and a counter electrode 25 is provided on the bottom surface of the heating space. However, the present invention is not limited to this configuration, and it is sufficient that the oscillation electrode 24 and the counter electrode 25 are configured to face each other across the heating space, and the same effect is achieved even if they are arranged upside down or facing each other in the left-right direction.

[0089] 5 and 7 in the above-mentioned embodiment 1, the oscillation electrode 24 is formed so that electric field concentration regions are dispersed on the electrode surface of the oscillation electrode 24, and uniform dielectric heating can be performed on the object to be heated accommodated in the heating chamber 55. As described in the embodiment 1, the electric field concentration regions are constituted by the edges of the openings formed on the electrode surface.

[0090] In the configuration of the heating device of the second embodiment, a positive electrode terminal 24a serving as a connection terminal is formed at the end of the oscillation electrode 24 in the arrangement direction of the matching circuit 23. This positive electrode terminal 24a is connected to a connection terminal extending from the matching circuit 23 in surface contact. In the second embodiment, it is fixed with a screw for easy assembly and maintenance. Also, similar to the configuration of the first embodiment, the terminal width w (see FIG. 4) of the positive electrode terminal 24a of the oscillation electrode 24 is formed to be significantly narrower than the electrode width W (see FIG. 4) of the oscillation electrode 24 (w<<W). Also, the terminal width of the negative electrode terminal 25a of the counter electrode 25 is formed to be significantly narrower than the electrode width of the counter electrode 25 from which the negative electrode terminal 25a protrudes.

[0091] In the counter electrode 25, the area facing the electrode surface 24b of the oscillation electrode 24 is the electrode surface 25b. As shown in FIG. 10, the electrode surface 25b of the counter electrode 25 is formed as a flat surface arranged at a high position that rises up so as to approach the oscillation electrode 24. On the other hand, in the counter electrode 25, the area 25a that does not face the electrode surface 24b of the oscillation electrode 24 is arranged at a low position lowered to the bottom side, and is configured not to function as a substantial electrode surface. A plurality of openings are formed in the area 25a of the counter electrode 25, and the facing area is reduced. In this way, the electrode surface 24b of the oscillation electrode 24 and the electrode surface 25b of the counter electrode 25 are configured to be close to each other, and openings are formed in the area 25a that does not face the electrode surface 24b of the oscillation electrode 24, so that a desired electric field is reliably formed only between the electrodes.

[0092] An inner surface member 32 is provided on the inner surface of the heating space of the heating chamber 55. The inner surface member 32 that defines the inner surface of the heating space is made of an electrically insulating material and is configured to cover the matching circuit 23 on the rear side, the electrode surface of the oscillation electrode 24 on the top side, and the electrode surface of the counter electrode 25 on the bottom side that constitute the dielectric heating mechanism. Since the inner surface member 32 is provided on the inner surface of the heating chamber 55 in this manner, the object to be heated contained in the heating space is prevented from being burned due to contact.

[0093] As described above, the heating device of the second embodiment has a dielectric heating mechanism and is provided with heating chamber 55 that accommodates an object to be heated. The heating device thus configured is incorporated into refrigerator 10, and is configured to introduce cold air into heating chamber 55.

[0094] Fig. 11 is a vertical cross-sectional view showing a state when the heating device is incorporated into refrigerator 10. As shown in Fig. 11, the heating device is incorporated into refrigerator 10 as a thawing module 60. In this manner, the heating device of the second embodiment is configured to be usable as thawing module 60 that provides a thawing function to refrigerator 10, and also to be usable as a high-frequency heating device having a normal dielectric heating function. Therefore, since the heating device of the second embodiment is configured such that the configuration having the dielectric heating function is formed into an integrated box body, it becomes possible to easily assemble a high-added-value refrigerator having a thawing function.

[0095] 10, in the refrigerator 10 incorporating the thawing module 60 (heating device), cold air generated by the cooling mechanism of the refrigerator 10 passes through the air passage 18 and is introduced from the top side of the heating chamber 55. On the top side of the heating chamber 55, a top-side electromagnetic wave shield 26 is provided directly below the air passage 18. Furthermore, an inner surface member 32 is provided below the top-side electromagnetic wave shield 26 with a predetermined space therebetween.

[0096] In the thawing module 60, the oscillation electrode 24 is disposed so as to contact the upper surface of the top surface side inner member 32, and an opening is formed penetrating the oscillation electrode 24 and the inner surface member 32. This opening corresponds to the electrode hole 41 of the oscillation electrode 24 and the cold air introduction hole 20, and serves as the cold air introduction hole through which cold air from the air passage 18 passes through the opening of the top surface side electromagnetic wave shield 26 and is introduced into the heating chamber 55.

[0097] In a refrigerator incorporating the thawing module 60 (heating device) of the second embodiment, the cold air introduced into the heating chamber 55 passes through an opening formed in the region 25a of the counter electrode 25 on the bottom side, and is discharged to the freezer chamber 6, which is a storage chamber disposed immediately below the heating chamber 55. Therefore, in the second embodiment, a communication opening 56 is formed in the partition between the heating chamber 55 of the refrigerator and the freezer chamber 6 immediately below it. Also, an opening (slit, hole, etc.) may be formed in the storage case 31 of the heating chamber 55 so that the cold air can flow smoothly from the storage case 31 to the communication opening 56. The opening formed in the storage case 31 is appropriately designed in consideration of the flow of the cold air. As a modified example of the configuration of the thawing module 60 (heating device) of the second embodiment, the return air passage (34) described in the first embodiment may be provided so that the cold air in the heating chamber passes through the back side of the heating chamber 55 and returns to the cooling mechanism of the refrigerator 10.

[0098] The configuration of the heating device of embodiment 2 also has a similar configuration to the oscillation electrode 24 and the counter electrode 25 described in embodiment 1 using Figures 5 to 7, and has a configuration in which a desired electric field is formed between the oscillation electrode 24 and the counter electrode 25, making it possible to perform uniform dielectric heating on the object to be heated.

[0099] As described above, in the heating device of the second embodiment, the electric field concentration regions are formed to be dispersed on the electrode surface of the oscillation electrode 24, so that uniform dielectric heating can be performed on the object to be heated housed in the heating chamber 55. By incorporating the heating device of the second embodiment as the thawing module 60 into the refrigerator 10, a refrigerator having an excellent thawing function can be easily manufactured.

[0100] As described above, in the present invention, a heating device can be provided that can uniformly generate an electric field between electrodes in dielectric heating. This heating device can be used to uniformly heat objects to be heated. Furthermore, by incorporating this heating device into a refrigerator, it is possible to construct a highly safe refrigerator that has reliable cooling and storage functions and is equipped with a storage compartment in which frozen items can be easily thawed to a high-quality state.

[0101] As described above, the heating device of the present invention can dielectrically heat the object to be heated to a desired state, and a refrigerator incorporating this heating device has the excellent effect of being able to defrost a frozen item in a desired state to a desired state in a short time. According to the present invention, the heating device having a dielectric heating mechanism made of semiconductor elements has a configuration that allows for a simple and compact structure that provides the excellent function of uniformly heating the object to be heated. Furthermore, a refrigerator incorporating this heating device can be made compact while still providing an excellent defrosting function.

[0102] Although the present invention has been described in detail in each embodiment, the disclosure of these embodiments may vary in details of construction, and substitutions, combinations, and changes in the order of elements in each embodiment may be made without departing from the scope and spirit of the invention as claimed. [Industrial Applicability]

[0103] The present invention provides a heating device capable of uniformly heating an object to be heated, as well as a refrigerator capable of freezing, storing, and thawing stored items to the desired state, thereby making it possible to provide products with high market value. [Explanation of symbols]

[0104] 1 Outer box 2 Inner box 3. Refrigerator 4 Ice Room 5 Freezing / thawing room 6 Freezer 7 Vegetable compartment 8 Machine room 9. Compressor 10. Refrigerator 11 Cooling room 12 Cooler 13 Cooling fan 14 Defrost heater 15 Drain pan 16 Drain tube 17 Evaporation dish 18 Wind path 19 Damper 20 Cool air intake 21 Cool air exhaust vent 22 Oscillator Circuit 23 Matching circuit 24 Oscillation electrode 25 Counter electrode 26 Top side electromagnetic shield 27 Rear electromagnetic shield 28 Front electromagnetic shield 29 Door 30 Electrode holding area 31 Storage Case 32 Inner surface material 33 Spacing Regulation Section 34 Return air duct 35 Cross rail (frame) 36 Gasket 37 First retaining claw (retaining member) 38 Second retaining claw (retaining member) 39 Door side electromagnetic shield 40 Insulation 41 Electrode hole (oscillating electrode) 42 Electrode hole (counter electrode) 47 Operation section 48 Power supply section 49 Temperature Sensor 50 Control section 51 Reflected wave detector

Claims

1. A heating chamber having a heating space for accommodating an object to be heated and having an openable and closable door on the front side; An oscillation electrode provided above the heating space and having an electrode surface on which an electric field concentration region is formed; a counter electrode provided below the heating space and having an electrode surface facing the electrode surface of the oscillation electrode; a high frequency electric field forming unit for forming a high frequency electric field to be applied between the one oscillation electrode and the one counter electrode; Equipped with the one oscillation electrode and the one counter electrode are a pair of electrodes whose electrode surfaces face each other, a flat spacer that connects the rear end of the one oscillation electrode and the rear end of the one counter electrode in a cantilever structure to maintain the first distance and the second distance such that a first distance between the front end of the one oscillation electrode and the front end of the one counter electrode is the same as a second distance between the rear end of the one oscillation electrode and the rear end of the one counter electrode, a heating device, wherein the electric field concentration region of the oscillation electrode is an edge portion of a plurality of openings formed in a region of the electrode surface of the oscillation electrode facing the electrode surface of the counter electrode.

2. The high frequency electric field forming unit includes a matching circuit for performing impedance matching, the matching circuit is electrically connected to a terminal provided at the rear end of the one oscillation electrode and a terminal provided at the rear end of the one counter electrode, The heating device according to claim 1 , wherein the spacing defining member holds the matching circuit.

3. 3. The heating device according to claim 1, wherein electric field concentration regions are formed in a dispersed manner on the electrode surface of the oscillation electrode.

4. The heating device according to claim 1 , wherein the opening portion formed in the electric field concentration region of the oscillation electrode is configured as an electrode hole or an electrode notch.

5. 5. The heating device according to claim 1, wherein an electric field concentration region is formed on an electrode surface of the counter electrode, and the counter electrode is disposed so as not to face the electric field concentration region of the oscillation electrode.

6. The heating device according to claim 5 , wherein electric field concentration regions are formed in a dispersed manner on the electrode surface of the counter electrode.

7. 7. The heating device according to claim 5, wherein the electric field concentration region of the counter electrode is constituted by an edge of an opening portion formed on the electrode surface.

8. The heating device according to claim 7 , wherein the opening portion formed in the electric field concentration region of the counter electrode is configured as an electrode hole or an electrode notch.

9. The heating device according to claim 1 , wherein the oscillation electrode and the counter electrode are not exposed to a heating space.

10. The heating device according to claim 1 , further comprising an inner surface member that constitutes an inner surface of the heating chamber, the inner surface member being configured to cover each of the opposing electrode surfaces of the oscillation electrode and the counter electrode.

11. The heating device according to claim 1 , further comprising an electromagnetic wave shield for suppressing radiation of electromagnetic waves from the oscillation electrode and the counter electrode to the outside of the device.

12. The heating device according to claim 1 , wherein the door is provided with an electromagnetic wave shield.

13. A refrigerator comprising the heating device according to any one of claims 1 to 12.

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