Induction heating type stove

Abstract

The present invention relates to an induction heating type stove, including: a housing; a cover plate combined with an upper end of the housing, an upper plate part in which an object to be heated is disposed being provided at a top surface of the cover plate; a work coil provided inside the housing; a thin film coated to the upper plate part and inductively heated by the work coil; and a heat insulating material provided between the upper plate part and the work coil, the thin film being formed to have at least one closed loop not including a central area of the work coil.

Description

Technical Field

[0001] This invention relates to an induction heating stove. More specifically, this invention relates to an induction heating stove coated with a thin film. Background Technology

[0002] Cooking appliances used in homes and restaurants in various ways to heat food. Gas stoves that use gas as fuel were widely used in the past, but in recent years, devices that use electricity to heat objects such as pots and pans have become increasingly popular.

[0003] The main methods of heating objects using electricity are resistance heating and induction heating. Resistance heating involves transferring heat generated when current flows through a non-metallic heating element such as a metal resistance wire or silicon carbide to the object being heated (e.g., a cooking container) via radiation or conduction. Induction heating, on the other hand, utilizes the magnetic field generated around a coil when a specified amount of high-frequency power is applied to it. This magnetic field induces eddy currents in the object being heated, which is made of metal, thus heating the object itself.

[0004] In recent years, induction heating has been widely used in cooktops.

[0005] However, induction heating stoves have a limitation: they can only heat magnetic materials. That is, if a non-magnetic material (e.g., heat-resistant glass, ceramics, etc.) is placed on the stove, the induction heating stove cannot heat that object.

[0006] To address the problems inherent in induction heating stoves, this invention aims to utilize a thin film. Specifically, the stove of this invention may include a thin film to which eddy currents are applied to heat a non-magnetic material. Furthermore, this thin film may be formed to have a skin depth greater than its thickness, thereby allowing the magnetic field generated by the operating coil to pass through the film and apply eddy currents to a magnetic material, thus also heating the magnetic material.

[0007] On the other hand, Korean Patent Publication No. 10-2005-0033551 discloses an electrical conductor disposed between a heating coil and a heated object. However, the electrical conductor differs from the film of the present invention in that it is inserted to reduce magnetic levitation. Furthermore, the electrical conductor is designed to be thicker than the skin depth, which is significantly different from the film described in the present invention.

[0008] On the other hand, by combining the closed loop formed by applying eddy currents to the thin film of the present invention with the magnetic field generated in the working coil, it is possible to prevent the magnetic field generated in the working coil from reaching the heated object. Therefore, when a magnetic body is placed on the stove, there is a problem of reduced heating efficiency. Summary of the Invention

[0009] The problem that the invention aims to solve

[0010] The purpose of this invention is to minimize the problem of reduced heating efficiency for magnetic materials in induction heating stoves capable of heating both magnetic and non-magnetic materials.

[0011] Technical solutions to the problem

[0012] The stove of this invention includes a thin film forming a closed loop excluding the center of the coil, thereby enabling an increase in the magnetic field applied to the magnetic body through the thin film.

[0013] The stove of this invention includes a thin film having a skin depth greater than its thickness, thereby enabling heating of both magnetic and non-magnetic materials.

[0014] Invention Effects

[0015] According to the present invention, both magnetic and non-magnetic materials can be heated by the same heating source, which has the advantage of improving heating performance by minimizing the reduction in heating efficiency of magnetic materials caused by the thin film. Attached Figure Description

[0016] Figure 1 This is a diagram illustrating an embodiment of the induction heating stove of the present invention.

[0017] Figure 2 This is a cross-sectional view showing an induction heating stove and a heated object according to an embodiment of the present invention.

[0018] Figure 3 This is a cross-sectional view showing an induction heating stove and a heated object according to another embodiment of the present invention.

[0019] Figure 4 and Figure 5 This is a graph illustrating the relationship between film thickness and skin depth.

[0020] Figure 6 and Figure 7 It is a graph illustrating the impedance changes between the thin film and the heated object, depending on the type of object being heated.

[0021] Figure 8 This is an example diagram showing the shape of the thin film of a comparative example of the present invention.

[0022] Figure 9 and Figure 10 This is an example diagram showing the shape of the thin film according to the first embodiment of the present invention.

[0023] Figure 11 This is an example diagram showing the shape of the thin film according to a second embodiment of the present invention.

[0024] Figure 12 This is an example diagram showing the shape of the thin film according to a third embodiment of the present invention.

[0025] Figure 13 This is an example diagram showing the shape of the thin film according to the fourth embodiment of the present invention.

[0026] Figure 14 This is an example diagram showing the shape of the thin film according to the fifth embodiment of the present invention.

[0027] Figure 15 This is a diagram illustrating the closed loop formed on the thin film and the central region of the working coil in an embodiment of the present invention. Detailed Implementation

[0028] Hereinafter, preferred embodiments of the present invention will be described in detail with reference to the accompanying drawings. In the drawings, the same reference numerals are used to refer to the same or similar constituent elements.

[0029] The following will describe an embodiment of the induction heating stove of the present invention.

[0030] Figure 1 This is a diagram illustrating an embodiment of the induction heating stove of the present invention. Figure 2 This is a cross-sectional view showing an induction heating stove and a heated object according to an embodiment of the present invention. Figure 3 This is a cross-sectional view showing an induction heating stove and a heated object according to another embodiment of the present invention.

[0031] First, refer to Figure 1 The induction heating stove 1 of this embodiment may include a shell 25, a cover plate 20, working coils WC1 and WC2 (i.e., the first working coil and the second working coil), and thin films TL1 and TL2 (i.e., the first thin film and the second thin film).

[0032] Working coils WC1 and WC2 can be provided in the housing 25.

[0033] For reference, in addition to the working coils WC1 and WC2, the housing 25 may be equipped with various devices related to the driving of the working coils (e.g., a power supply unit that provides AC power, a rectifier unit that rectifies the AC power from the power supply unit into DC power, an inverter unit that converts the DC power rectified by the rectifier unit into resonant current and provides it to the working coils through a switching action, a control module that controls the operation of various devices in the induction heating stove 1, a relay or semiconductor switch that turns the working coils on or off, etc.), but a detailed description of these will be omitted.

[0034] The cover plate 20 can be combined with the upper end of the housing 25, and an upper plate portion 15 for placing the object to be heated (not shown) can be provided on its top surface.

[0035] Specifically, the cover 20 may include an upper plate portion 15 for placing heated objects such as cooking containers.

[0036] Here, for example, the upper plate 15 can be made of glass material (e.g., ceramic glass).

[0037] Additionally, an input interface (not shown) may be provided on the upper plate 15, which receives input from the user and transmits the corresponding input to the input interface control module (not shown). Of course, the input interface may also be located in other positions besides the upper plate 15.

[0038] For reference, the input interface is a module used to input the user's desired heating intensity or the driving time of the induction heating stove 1, and can be implemented in various ways such as physical buttons or a touch panel. Additionally, the input interface may include, for example, a power button, a lock button, a power level adjustment button (+, -), a timer adjustment button (+, -), and a charging mode button. Furthermore, the input interface can transmit the input received from the user to an input interface control module (not shown), and the input interface control module can transmit the input to the aforementioned control module (i.e., the inverter control module). Moreover, the aforementioned control module can control the operation of various devices (e.g., the operating coil) based on the input received from the input interface control module (i.e., the user's input); details of this will be omitted.

[0039] On the other hand, the upper plate 15 can visually display, in the shape of a stove opening, whether the working coils WC1 and WC2 are driven and the heating intensity (i.e., firepower). This stove opening shape can be displayed by an indicator light (not shown) consisting of a plurality of light-emitting elements (e.g., LEDs) disposed within the housing 25.

[0040] The working coils WC1 and WC2 can be placed inside the housing 25 to heat the object being heated.

[0041] Specifically, the working coil WC can be controlled and driven by the aforementioned control module (not shown). When the object to be heated is placed on the upper plate 15, it can be driven by the control module.

[0042] In addition, the working coil WC can directly heat magnetic objects (i.e., magnetic bodies), while non-magnetic objects (i.e., non-magnetic bodies) can be indirectly heated through the thin film TL described later.

[0043] In addition, the working coil WC can use induction heating to heat the object being heated, and can be configured to overlap the thin film TL in the longitudinal direction (i.e., vertical or up-down direction).

[0044] For reference only. Figure 1 The example shown depicts two working coils WC1 and WC2 disposed in the housing 25, but it is not limited to this. That is, one or more working coils may be disposed in the housing 25, but for ease of explanation, in the embodiment of the present invention, two working coils WC1 and WC2 disposed in the housing 25 will be used as an example for explanation.

[0045] A thin film TL can be coated onto the upper plate 15 to heat non-magnetic parts in the object being heated. The thin film TL can be induction heated by a working coil WC.

[0046] The thin film TL can be coated on the top or bottom surface of the upper plate portion 15. For example, as... Figure 2 As shown, the thin film TL can be coated on the top surface of the upper plate 15, or as... Figure 3 As shown, the thin film TL can be coated on the bottom surface of the upper plate 15.

[0047] The thin film TL can be configured to overlap with the working coil WC in the longitudinal direction (i.e., vertical or up-down direction). Therefore, the object being heated can be heated regardless of its position or type.

[0048] In addition, thin film TL can have at least one of the properties of magnetic and non-magnetic (i.e., magnetic, non-magnetic, or both).

[0049] Furthermore, for example, the thin film TL can be made of a conductive material (e.g., aluminum), and as shown, can be coated on the upper plate portion 15 in a shape consisting of repeated rings with different diameters, but is not limited thereto. That is, the thin film TL can also be made of other materials that are not conductive. Furthermore, the thin film TL can also be formed into other shapes that are not consisting of repeated rings with different diameters. Figures 10 to 15 The various shapes of thin film TL are described in more detail.

[0050] For reference only. Figure 2 and Figure 3 The diagram shows a single thin film TL, but it is not limited to this. That is, multiple thin films can also be coated, but for the sake of illustration, we will use coating a single thin film TL as an example.

[0051] The thin film TL will be explained in more detail later.

[0052] Next, refer to Figure 2 and Figure 3 The induction heating stove 1 of this embodiment may further include at least some or all of the following: heat insulation material 35, shielding plate 45, support member 50, and cooling fan 55.

[0053] The heat insulation material 35 can be placed between the upper plate 15 and the working coil WC.

[0054] Specifically, the heat insulation material 35 can be installed below the upper plate 15, and the working coil WC can be arranged below it.

[0055] This heat insulation material 35 can block the heat generated when the thin film TL or the heated object HO is heated by the driving of the working coil WC from being transferred to the working coil WC.

[0056] That is, if the thin film TL or the heated object HO is heated by electromagnetic induction through the working coil WC, the heat of the thin film TL or the heated object HO will be transferred to the upper plate 15, and the heat of the upper plate 15 will be transferred to the working coil WC again, which may damage the working coil WC.

[0057] As described above, the heat insulation material 35 blocks the heat transferred to the working coil WC, thereby preventing the working coil WC from being damaged by heat and thus preventing the heating performance of the working coil WC from decreasing.

[0058] For reference, although not a necessary component, a partition (not shown) may also be placed between the working coil WC and the insulation material 35.

[0059] Specifically, a partition (not shown) can be inserted between the working coil WC and the heat insulation material 35, so that the working coil WC and the heat insulation material 35 do not come into direct contact. Thus, the partition (not shown) can prevent the heat generated when the working coil WC is driven to heat the thin film TL or the heated object HO from being transferred to the working coil WC through the heat insulation material 35.

[0060] That is, the partition (not shown) can share part of the function of the heat insulation material 35, thereby minimizing the thickness of the heat insulation material 35, which in turn minimizes the gap between the heated object HO and the working coil WC.

[0061] Additionally, a plurality of partitions (not shown) may be provided, and the partitions may be arranged to be spaced apart from each other between the working coil WC and the heat insulation material 35. Thus, air drawn into the interior of the housing 25 by the cooling fan 55 (described later) may be guided to the working coil WC by the partitions.

[0062] That is, the baffle can guide the air flowing into the interior of the housing 25 through the cooling fan 55 to be properly delivered to the working coil WC, thereby improving the cooling efficiency of the working coil WC.

[0063] The shielding plate 45 can be installed on the bottom surface of the working coil WC to block the downward magnetic field generated when the working coil WC is driven.

[0064] Specifically, the shielding plate 45 can block the downward magnetic field generated when the working coil WC is driven, and can be supported upward by the support member 50.

[0065] The support member 50 can be disposed between the bottom surface of the shielding plate 45 and the lower plate of the housing 25 to support the shielding plate 45 upward.

[0066] Specifically, the support member 50 can indirectly support the heat insulation material 35 and the working coil WC upward by supporting the shielding plate 45 upward, so that the heat insulation material 35 can be closely attached to the upper plate 15.

[0067] As a result, the distance between the working coil WC and the heated object HO can be maintained constant.

[0068] For reference, the support member 50 may include, for example, an elastic body (e.g., a spring) for supporting the shielding plate 45 upwards, but is not limited thereto. Furthermore, since the support member 50 is not an essential component, it can be omitted from the induction heating stove 1.

[0069] A cooling fan 55 can be located inside the housing 25 to cool the working coil WC.

[0070] Specifically, the cooling fan 55 can be driven by the aforementioned control module and can be installed on the side wall of the housing 25. Of course, the cooling fan 55 can also be installed in other locations besides the side wall of the housing 25, but in this embodiment of the invention, for ease of explanation, the example of the cooling fan 55 being installed on the side wall of the housing 25 will be used for illustration.

[0071] In addition, such as Figure 2 and Figure 3 As shown, the cooling fan 55 can draw in air from outside the housing 25 and deliver it to the working coil WC, or it can draw in air (especially hot air) from inside the housing 25 and exhaust it to the outside of the housing 25.

[0072] This enables effective cooling of the components inside the housing 25 (especially the working coil WC).

[0073] Furthermore, as described above, the air supplied by the cooling fan 55 to the outside of the housing 25 of the working coil WC can be guided to the working coil WC by the partition. As a result, the working coil WC can be directly and effectively cooled, thereby improving the durability of the working coil WC (i.e., durability improvement based on preventing thermal damage).

[0074] As described above, an induction heating stove 1 according to an embodiment of the present invention may have the above-described features and configuration, and in the following description, reference will be made to... Figures 4 to 7 The characteristics and composition of the above-mentioned thin film will be explained in more detail.

[0075] Figure 4 and Figure 5 This is a graph illustrating the relationship between film thickness and skin depth. Figure 6 and Figure 7 It is a graph illustrating the impedance changes between the thin film and the heated object, depending on the type of object being heated.

[0076] Thin-film TL can be made from materials with low relative permeability.

[0077] Specifically, due to the low relative permeability of thin-film TL, the skin depth of thin-film TL can be relatively deep. Here, skin depth refers to the depth of current penetration from the material surface, and relative permeability can be inversely proportional to skin depth. Therefore, the lower the relative permeability of thin-film TL, the deeper the skin depth of thin-film TL.

[0078] In addition, the skin depth of the thin film TL can be greater than the thickness of the thin film TL. That is, the thin film TL has a relatively thin thickness (e.g., 0.1 μm to 1,000 μm), while the skin depth of the thin film TL is greater than the thickness of the thin film TL. Therefore, the magnetic field generated by the working coil WC passes through the thin film TL and is transmitted to the heated object HO, thereby inducing eddy currents in the heated object HO.

[0079] That is, such as Figure 4 As shown, when the skin depth of the thin film TL is thinner than the thickness of the thin film TL, the magnetic field generated by the working coil WC may have difficulty reaching the heated object HO.

[0080] However, as Figure 5As shown, when the skin depth of the thin film TL is deeper than the thickness of the thin film TL, the magnetic field generated by the working coil WC can reach the heated object HO. That is, in the embodiment of the present invention, the skin depth of the thin film TL is deeper than the thickness of the thin film TL, so most of the magnetic field generated by the working coil WC passes through the thin film TL and is transmitted to the heated object HO and consumed, thereby mainly heating the heated object HO.

[0081] On the other hand, since the thin film TL has a relatively thin thickness as described above, it can have a resistance value that can be heated by the working coil WC.

[0082] Specifically, the thickness of the thin film TL can be inversely proportional to the resistance value (i.e., surface resistance value) of the thin film TL. That is, the thinner the thin film TL coated onto the upper plate portion 15, the greater the resistance value (i.e., surface resistance value) of the thin film TL. Therefore, the thin film TL can be coated onto the upper plate portion 15 more thinly, so that its characteristics can be changed to a load that can be heated.

[0083] For reference, for example, a thin film TL can have a thickness between 0.1 μm and 1,000 μm, but is not limited to this.

[0084] The thin film TL, which has the characteristics described above, exists for heating non-magnetic materials. Therefore, the impedance characteristics between the thin film TL and the heated object HO can be changed depending on whether the heated object HO disposed on the upper plate 15 is a magnetic or non-magnetic material.

[0085] First, the following explanation addresses the case where the heated object HO is a magnetic material.

[0086] When a magnetic object HO is placed on the upper plate 15 and the working coil WC is driven, as follows: Figure 6 As shown, the resistive component R1 and inductive component L1 of the magnetic heated object HO can form an equivalent circuit with the resistive component R2 and inductive component L2 of the thin film TL.

[0087] In this case, the impedance of the heated object HO with magnetism in the equivalent circuit (i.e., the impedance composed of R1 and L1) can be less than the impedance of the thin film TL (i.e., the impedance composed of R2 and L2).

[0088] Therefore, with the equivalent circuit described above formed, the magnitude of the eddy current I1 applied to the magnetic heated object HO can be greater than the magnitude of the eddy current I2 applied to the thin film TL. Thus, most of the eddy current generated by the working coil WC can be applied to the heated object HO to heat it.

[0089] That is, when the object being heated HO is a magnetic body, most of the eddy current is applied to the object being heated HO due to the formation of the above equivalent circuit, so the working coil WC can directly heat the object being heated HO.

[0090] Of course, some eddy current is also applied to the thin film TL, causing the thin film TL to be slightly heated. Therefore, the object HO can be indirectly and slightly heated by the thin film TL. In this case, the working coil WC can be the main heating source, and the thin film TL can be the secondary heating source. However, the degree to which the object HO is indirectly heated by the thin film TL may be meaningless compared to the degree to which the object HO is directly heated by the working coil WC.

[0091] Next, the case where the heated object is a non-magnetic body will be explained below.

[0092] When a non-magnetic heated object HO is placed on the upper plate 15 and the working coil WC is driven, the non-magnetic heated object HO may not have impedance, while the thin film TL may have impedance. That is, the resistive component R and the inductive component L may exist only in the thin film TL.

[0093] Therefore, when a non-magnetic heated object HO is placed on the upper plate 15 and the working coil WC is driven, as Figure 7 As shown, the resistive component R and the inductive component L of the thin film TL can form an equivalent circuit.

[0094] Therefore, the eddy current I can be applied only to the thin film TL, and the eddy current is not applied to the non-magnetic heated object HO. More specifically, the eddy current I generated by the working coil WC can be applied only to the thin film TL, thereby heating the thin film TL.

[0095] That is, when the object being heated, HO, is a non-magnetic body, as described above, the eddy current I is applied to the thin film TL to heat the thin film TL. Therefore, the non-magnetic object being heated, HO, can be indirectly heated by the thin film TL heated by the working coil WC. In this case, the thin film TL can be the main heating source.

[0096] In summary, regardless of whether the heated object HO is magnetic or non-magnetic, the heated object HO can be directly or indirectly heated by a heat source, which is the working coil WC. That is, when the heated object HO is magnetic, the working coil WC can directly heat the heated object HO; when the heated object HO is non-magnetic, the thin film TL heated by the working coil WC can indirectly heat the heated object HO.

[0097] As described above, the induction heating stove 1 of this embodiment can heat both magnetic and non-magnetic materials. Therefore, regardless of the placement and type of the object to be heated (HO), it can be heated. Thus, users can place the object to be heated in any heating area on the upper plate 15 without needing to determine whether the object to be heated (HO) is magnetic or non-magnetic, thereby improving ease of use.

[0098] Furthermore, the induction heating stove 1 of this embodiment can directly or indirectly heat the object being heated using the same heat source, thus eliminating the need for an additional heating plate or radiant heater. This not only improves heating efficiency but also reduces material costs.

[0099] On the other hand, the heating performance for magnetic and non-magnetic materials may differ depending on the shape and thickness of the thin film TL. In particular, when the object being heated, HO, is magnetic, both the working coil WC and the thin film TL heat it. Therefore, depending on the shape and thickness of the thin film TL, the amount of energy generated by the object HO and the thin film TL will differ, resulting in differences in the temperature and time required to heat the object HO. For example, depending on the shape and thickness of the thin film TL, the amount of energy generated by the thin film TL may be greater than that generated by the object HO, which is magnetic. In this case, the time required to heat the object HO to a specific temperature may be excessively long. Therefore, a design is needed that ensures heating performance separately for the case where the thin film TL is the primary heating source and the case where it is the secondary heating source.

[0100] Figure 8 This is an example diagram showing the shape of the thin film of a comparative example of the present invention.

[0101] In a comparative example of the present invention, the thin film TL can be ring-shaped. The eddy current (EC) applied to the ring-shaped thin film TL as described above can form a closed loop including the center area of ​​the working coil (CC).

[0102] The center region CC of the working coil can refer to the area that overlaps with the center of the working coil WC in the vertical direction. The center of the working coil WC can include the area from the exact midpoint of the working coil WC and the area at a specified distance from the exact midpoint of the working coil WC.

[0103] As described above, the coupling force between the thin film TL, which is formed such that the closed loop includes the central region CC of the working coil, and the magnetic field generated in the working coil WC can be relatively strong.

[0104] Therefore, when the heated object HO, which is a magnetic body, is placed on the upper plate 15, since there are more magnetic fields coupled to the thin film TL in the magnetic field generated by the working coil WC, the magnetic field reaching the heated object HO will be reduced, and thus the heating performance of the heated object HO will decrease.

[0105] Therefore, the stove 1 of the present invention may include a thin film TL formed as a closed loop having at least one central region CC excluding the working coil, in order to improve the heating performance of the heated object HO, which is a magnetic body.

[0106] Figure 9 and Figure 10 This is an example diagram showing the shape of the thin film according to the first embodiment of the present invention.

[0107] According to a first embodiment of the present invention, the thin film TL may be composed of a plurality of thin film portions TL-1 and TL-2. The plurality of thin film portions TL-1 and TL-2 may include a first thin film portion TL-1 and a second thin film portion TL-2.

[0108] The first thin film portion TL-1 and the second thin film portion TL-2 can each be configured to be detached from the central region CC of the working coil. That is, the first thin film portion TL-1 and the second thin film portion TL-2 can each be configured in a region outside the central region CC of the working coil. The first thin film portion TL-1 and the second thin film portion TL-2 can be configured symmetrically with respect to the central region CC of the working coil.

[0109] For example, the first thin film portion TL-1 and the second thin film portion TL-2 can each be formed into an inwardly recessed semi-circular shape. The first eddy current EC-1 applied to the first thin film portion TL-1 can form a closed loop that does not pass through the central region CC of the working coil, and the second eddy current EC-2 applied to the second thin film portion TL-2 can form a closed loop that does not pass through the central region CC of the working coil. Therefore, a closed loop excluding the central region CC of the working coil can be formed in the thin film TL. In this case, the coupling force with the magnetic field generated by the working coil WC may be greater than... Figure 8 The thin film shown has weak TL.

[0110] Therefore, when the heated object HO, which is a magnetic body, is placed on the induction heating stove 1, the magnetic field generated by the working coil WC passes through... Figure 9 or Figure 10 The magnetic field reaching the heated object HO through the thin film TL shown can be greater than the magnetic field generated by the working coil WC. Figure 8 The thin film TL shown reaches the magnetic field of the heated object HO. Therefore, the induction heating stove 1 includes, as shown... Figure 9 or Figure 10In the case of the thin film TL shown, it has the advantage of improving the heating performance of the heated object HO, which is a magnetic material.

[0111] On the other hand, the sizes of the recessed regions formed in the first thin film portion TL-1 and the second thin film portion TL-2 can be different. For example, when Figure 9 The dimensions of the recessed regions formed in the first thin film portion TL-1 and the second thin film portion TL-2 shown are the first dimensions. Figure 10 When the size of the recessed regions formed in the first thin film portion TL-1 and the second thin film portion TL-2 is the second size, the second size can be larger than the first size. The larger the size of the recessed region, the weaker the coupling force between the thin film TL and the magnetic field generated by the working coil WC may be. The size of the recessed region can be changed according to the material, thickness, etc. of the thin film TL.

[0112] Figure 11 This is an example diagram illustrating the shape of the thin film according to a second embodiment of the present invention.

[0113] According to a second embodiment of the present invention, the thin film TL may be composed of a plurality of thin film portions TL-1 and TL-2. The plurality of thin film portions TL-1 and TL-2 may include a first thin film portion TL-1 and a second thin film portion TL-2.

[0114] The first thin film portion TL-1 and the second thin film portion TL-2 can each be configured to be detached from the central region CC of the working coil. That is, the first thin film portion TL-1 and the second thin film portion TL-2 can each be configured in a region outside the central region CC of the working coil. The first thin film portion TL-1 and the second thin film portion TL-2 can be configured symmetrically with respect to the central region CC of the working coil.

[0115] For example, the first thin film portion TL-1 and the second thin film portion TL-2 can each be formed into an inwardly recessed semi-circular shape, and at least one protrusion B can be formed in the recessed region. The protrusion B can be formed from the inside of the thin film portions TL-1 and TL-2 towards the central region CC of the working coil. The protrusion B can be sized so that eddy currents EC-1 and EC-2 do not flow through it. That is, eddy currents EC-1 and EC-2 do not flow through the protrusion B. Since eddy currents EC-1 and EC-2 do not flow through the protrusion B as described above, they are not coupled to a magnetic field.

[0116] Furthermore, protrusion B can diffuse the heat generated in thin films TL-1 and TL-2 to the central region CC of the working coil. Therefore, it has the advantage of minimizing overheating of thin films TL-1 and TL-2 and uniformly dispersing the heat generated in thin films TL-1 and TL-2.

[0117] The first eddy current EC-1 applied to the first thin film portion TL-1 can form a closed loop that does not pass through the central region CC of the working coil, and the second eddy current EC-2 applied to the second thin film portion TL-2 can form a closed loop that does not pass through the central region CC of the working coil. Therefore, a closed loop excluding the central region CC of the working coil can be formed in the thin film TL. In this case, the coupling force with the magnetic field generated by the working coil WC may be greater than... Figure 8 The thin film shown has weak TL.

[0118] Therefore, when the heated object HO, which is a magnetic body, is placed on the induction heating stove 1, the magnetic field generated by the working coil WC passes through... Figure 11 The magnetic field reaching the heated object HO through the thin film TL shown can be greater than the magnetic field generated by the working coil WC. Figure 8 The thin film TL shown reaches the magnetic field of the heated object HO. Therefore, the induction heating stove 1 includes, as shown... Figure 11 In the case of the thin film TL shown, it has the advantage of improving the heating performance of the heated object HO, which is a magnetic material.

[0119] Figure 12 This is an example diagram showing the shape of the thin film according to a third embodiment of the present invention.

[0120] According to a third embodiment of the present invention, the thin film TL can be horseshoe-shaped. The thin film TL can have an open region S in a ring. Thus, the eddy current EC applied to the thin film TL can form a closed loop that does not pass through the central region CC of the working coil. Therefore, a closed loop excluding the central region CC of the working coil can be formed in the thin film TL. In this case, the coupling force with the magnetic field generated by the working coil WC may be greater than... Figure 8 The thin film shown has weak TL.

[0121] Therefore, when the heated object HO, which is a magnetic body, is placed on the induction heating stove 1, the magnetic field generated by the working coil WC passes through... Figure 12 The magnetic field reaching the heated object HO through the thin film TL shown can be greater than the magnetic field generated by the working coil WC. Figure 8 The thin film TL shown reaches the magnetic field of the heated object HO. Therefore, the induction heating stove 1 includes, as shown... Figure 12 In the case of the thin film TL shown, it has the advantage of improving the heating performance of the heated object HO, which is a magnetic material.

[0122] Figure 13 This is an example diagram showing the shape of the thin film according to the fourth embodiment of the present invention.

[0123] According to a fourth embodiment of the present invention, the thin film TL may be composed of a plurality of thin film portions TL-1, TL-2, TL-3, and TL-4. The plurality of thin film portions TL-1, TL-2, TL-3, and TL-4 may include a first thin film portion TL-1, a second thin film portion TL-2, a third thin film portion TL-3, and a fourth thin film portion TL-4.

[0124] The first to fourth thin film portions TL-1, TL-2, TL-3, and TL-4 can each be configured to be detached from the central region CC of the working coil. That is, the first to fourth thin film portions TL-1, TL-2, TL-3, and TL-4 can each be configured in a region outside the central region CC of the working coil. The first to fourth thin film portions TL-1, TL-2, TL-3, and TL-4 can be configured symmetrically with respect to the central region CC of the working coil.

[0125] The first to fourth film portions TL-1, TL-2, TL-3, and TL-4 can be circular or elliptical in shape, but this is only an example. That is, the first to fourth film portions TL-1, TL-2, TL-3, and TL-4 can also be formed into triangular, quadrilateral, or other shapes.

[0126] Eddy currents EC can be formed in the first to fourth thin film sections TL-1, TL-2, TL-3, and TL-4, respectively. These eddy currents EC can form closed loops that do not pass through the central region CC of the working coil. Therefore, a closed loop excluding the central region CC of the working coil can be formed in the thin film TL. In this case, the coupling force with the magnetic field generated by the working coil WC may be greater than... Figure 8 The thin film shown has weak TL.

[0127] Therefore, when the heated object HO, which is a magnetic body, is placed on the induction heating stove 1, the magnetic field generated by the working coil WC passes through... Figure 13 The magnetic field reaching the heated object HO through the thin film TL shown can be greater than the magnetic field generated by the working coil WC. Figure 8 The thin film TL shown reaches the magnetic field of the heated object HO. Therefore, the induction heating stove 1 includes, as shown... Figure 13 In the case of the thin film TL shown, it has the advantage of improving the heating performance of the heated object HO, which is a magnetic material.

[0128] Figure 14 This is an example diagram showing the shape of the thin film according to the fifth embodiment of the present invention.

[0129] According to a fifth embodiment of the present invention, the thin film TL may be composed of a plurality of thin film portions TL-1, TL-2, and TL-3. The plurality of thin film portions TL-1, TL-2, and TL-3 may include a first thin film portion TL-1, a second thin film portion TL-2, and a third thin film portion TL-3.

[0130] The first to third thin film portions TL-1, TL-2, and TL-3 can each be configured to be located outside the central region CC of the working coil. That is, the first to third thin film portions TL-1, TL-2, and TL-3 can each be configured in a region outside the central region CC of the working coil.

[0131] For example, the first thin film portion TL-1 and the second thin film portion TL-2 can each be formed into an inner concave semi-circular shape. The first eddy current EC-1 applied to the first thin film portion TL-1 can form a closed loop that does not pass through the central region CC of the working coil, and the second eddy current EC-2 applied to the second thin film portion TL-2 can form a closed loop that does not pass through the central region CC of the working coil.

[0132] Furthermore, the third thin film portion TL-3 can be in the shape of a ring. The third thin film portion TL-3 can also have an open shape in the central region CC of the working coil.

[0133] like Figure 14 As shown, the third film portion TL-3 can be disposed inside the first film portion TL-1 and the second film portion TL-2. Alternatively, the third film portion TL-3 can also be disposed outside the first film portion TL-1 and the second film portion TL-2.

[0134] There can be one or more third film portions TL-3. When there are multiple third film portions TL-3, the multiple third film portions TL-3 can be disposed inside or outside the first film portion TL-1 and the second film portion TL-2, respectively.

[0135] A closed loop, excluding the central region CC of the working coil, can be formed in the thin film TL through the first thin film portion TL-1 and the second thin film portion TL-2. Therefore, the coupling force with the magnetic field generated by the working coil WC may be greater than that of the working coil WC. Figure 8 The thin film shown has weak TL.

[0136] Therefore, when the heated object HO, which is a magnetic body, is placed on the induction heating stove 1, the magnetic field generated by the working coil WC passes through... Figure 14 The magnetic field reaching the heated object HO through the thin film TL shown can be greater than the magnetic field generated by the working coil WC. Figure 8The thin film TL shown reaches the magnetic field of the heated object HO. Therefore, the induction heating stove 1 includes, as shown... Figure 14 In the case of the thin film TL shown, it has the advantage of improving the heating performance of the heated object HO, which is a magnetic material.

[0137] on the other hand, Figures 9 to 14 The shapes of the thin film TL shown are merely exemplary and are therefore not limited thereto. That is, the thin film TL of embodiments of the present invention can include all shapes formed having at least one closed loop excluding a central region CC of a working coil.

[0138] Figure 15 This is a diagram illustrating the closed loop formed on the thin film and the central region of the working coil in an embodiment of the present invention.

[0139] Figure 15 The shape of the thin film TL is as follows Figure 9 The example shown is merely illustrative and is not limited to this.

[0140] Reference Figure 15 In the thin film TL, a closed loop formed by a first eddy current EC-1 and a closed loop formed by a second eddy current EC-2 can be formed. At this time, at least one of the closed loops formed by the first eddy current EC-1 and the second eddy current EC-2 may not include the central region CC of the working coil.

[0141] The central region CC of the working coil can refer to the area that overlaps with the center C of the working coil WC in the vertical direction.

[0142] That is, at least one closed loop formed on the thin film TL can be formed so that it does not overlap with the central region CC of the working coil when viewed from above.

[0143] As described above, if the closed loop formed on the thin film TL does not include the central region CC of the working coil, the area of ​​the eddy current applied to the thin film TL is small, thus weakening the coupling force with the magnetic field generated by the working coil WC. Consequently, the magnetic field coupled with the heated object HO, which is a magnetic material, can be increased. Therefore, when the heated object HO, which is a magnetic material, is arranged on the induction heating stove 1, it has the advantage of improved heating performance.

[0144] However, in the induction heating stove 1, the heating performance of the heated object HO, which is a non-magnetic body, may be reduced compared to the case where a thin film TL is formed as a closed loop having only a central region CC including a working coil.

[0145] Tables 1 to 3 below show the frequency, equivalent resistance, increased inductance, peak current, output power, the ratio of power consumed by the thin film to the output power, and the ratio of power consumed by the heated object to the output power, respectively, for non-magnetic objects (e.g., glass loads) and magnetic objects (e.g., cladding loads). In particular, Table 1 can represent cases where the thin film TL is made of silver material. Figure 9 The measured values ​​for the shape shown in Table 2 can represent the thin film TL as a silver material. Figure 10 The measured values ​​for the shape shown in Table 3 can represent the thin film TL as a silver material. Figure 11 The measured values ​​when the shape is shown.

[0146] [Table 1]

[0147]

[0148] [Table 2]

[0149]

[0150] [Table 3]

[0151]

[0152] As described above, depending on the shape of the thin film TL, the ratio of power consumed by the thin film to the output power and the ratio of power consumed by the heated object to the output power may differ. Therefore, the stove 1 of the present invention can be based on target output to non-magnetic and magnetic bodies respectively, including any of various thin film TLs formed as closed loops having at least one central region CC excluding the working coil. Thus, the present invention can provide an induction heating stove 1 that minimizes the reduction in heating efficiency to magnetic bodies and can heat non-magnetic bodies to the target power.

[0153] On the other hand, according to another embodiment of the present invention, the working coil WC can be redesigned to minimize the reduction in heating performance of the non-magnetic heated container HO. Specifically, according to another embodiment of the present invention, the induction heating stove 1 may include a thin film TL formed as a closed loop having at least one central region CC excluding the working coil, in which case the working coil WC may be formed as a plurality of layers, or may be formed as a predetermined number of turns or more.

[0154] [Table 4]

[0155]

[0156] Table 4 above can be an induction heating stove 1, including, for example Figure 11The following table shows the frequency, equivalent resistance, increased inductance, peak current, and output power of a thin film TL of silver material with a shape shown, and the working coil WC formed as a two-layer structure with a predetermined number of turns (e.g., 17 turns). Compared with Table 3, it can be confirmed that the output power increases or decreases.

[0157] As described above, according to another embodiment of the present invention, the induction heating stove 1 includes a thin film TL formed as having at least one closed loop excluding a central region CC of a working coil, and is formed as a plurality of layers or as a predetermined number of turns, thereby having the advantage of improving the heating performance of the heated container HO, which is a magnetic body, and minimizing the reduction in the heating performance of the heated container HO, which is a non-magnetic body.

[0158] The above description is merely an exemplary illustration of the technical concept of the present invention. Those skilled in the art to which this invention pertains can make various modifications and variations without departing from the essential characteristics of the present invention.

[0159] Therefore, the embodiments disclosed in this invention are used to explain rather than limit the technical concept of the invention, and the scope of the technical concept of the invention is not limited by these embodiments.

[0160] The scope of protection of this invention shall be interpreted by the appended claims, and all desired technical ideas within its equivalent scope shall be understood to be included within the scope of the claims of this invention.

Claims

1. An induction heating stove, in, include: case; A cover plate is attached to the upper end of the housing, and an upper plate portion for placing the object to be heated is provided on the top surface of the cover plate; The working coil is disposed inside the housing; A thin film is coated onto the upper plate and induction heated by the working coil; and Thermal insulation material is disposed between the upper plate and the working coil. The thin film is formed as a closed loop having at least one central region that does not include the working coil.

2. The induction heating stove according to claim 1, wherein, When viewed from above, the closed loop formed in the thin film is formed so as not to overlap with the central region of the working coil.

3. The induction heating stove according to claim 1, wherein, The skin depth of the film is greater than the thickness of the film.

4. The induction heating stove according to claim 1, wherein, The thin film is composed of at least one thin film portion configured to be detached from the central region of the working coil.

5. The induction heating stove according to claim 4, wherein, The thin film portion includes a first thin film portion and a second thin film portion configured to be detached from the central region of the working coil.

6. The induction heating stove according to claim 5, wherein, At least one protrusion that does not carry eddy current is formed in the first thin film portion and the second thin film portion, respectively.

7. The induction heating stove according to claim 6, wherein, The protrusions are formed from the inner sides of the first and second film portions toward the central region of the working coil.

8. The induction heating stove according to claim 4, wherein, The thin film includes: The first thin film portion is formed as a closed loop having a central region excluding the working coil; and The second thin film portion is formed as a closed loop having a central region including the working coil.

9. The induction heating stove according to claim 8, wherein, The second film portion is disposed inside or outside the first film portion.

10. The induction heating stove according to claim 1, wherein, When a magnetic object to be heated is disposed on the top surface of the upper plate, the magnetic object is directly heated by the working coil. When a non-magnetic object to be heated is disposed on the top surface of the upper plate, the non-magnetic object to be heated is heated by the thin film heated by the working coil.

Images