Induction heating device including coil substrate

Abstract

This induction heating device may include an inverter circuit for driving a heating coil. The induction heating device may include a coil substrate including a plurality of pattern layers on which a heating coil is printed to form a coil pattern. The coil patterns which are respectively formed on the plurality of pattern layers are electrically connected to each other, and a first end of each of the coil patterns may be connected to an input terminal and a second end of each of the coil patterns may be connected to an output terminal. According to an embodiment of the present disclosure, at least one of the coil patterns branches in parallel at a branch point located between the input terminal and the output terminal, and joins at a junction point located between the input terminal and the output terminal.

Description

Induction heating device including coil substrate

[0001] The present disclosure relates to a heating coil substrate used in an induction heating device or non-contact power supply.

[0002] A variety of cooking appliances are used to heat food in homes and restaurants. While gas-fueled stoves have traditionally been widely used, recent developments have seen the proliferation of cooking appliances that use electricity to heat objects, such as cooking pots, without relying on gas.

[0003] Methods for heating a subject using electricity are broadly divided into resistance heating and induction heating. Resistance heating is a method of heating a subject by transferring the heat generated when current is passed through a metallic resistance wire or a non-metallic heating element such as silicon carbide to the subject (e.g., a cooking vessel) through radiation or conduction. Induction heating is a method of generating eddy currents in a subject made of metallic components by utilizing the magnetic field generated around the coil when a certain amount of high-frequency power is applied to the coil, thereby heating the subject itself. Among these, induction ranges that apply the induction heating method typically have working coils (heating coils) in corresponding areas to heat each of a plurality of subjects (cooking vessels).

[0004] An induction range is a cooking appliance that utilizes the principle of induction heating. Commonly called induction, induction heating device, or induction cooking device, induction ranges do not consume oxygen and do not emit waste gases compared to gas ranges, which can reduce indoor air pollution and temperature increases. Furthermore, induction ranges utilize an indirect method of inducing heat to the heated object itself, resulting in high energy efficiency and stability. Furthermore, since heat is generated only within the heated object itself and not the contact surface, there is a low risk of burns, which has led to a continued increase in demand for induction ranges.

[0005] Recently, induction ranges have been developed that allow the heated object to be freely placed anywhere on the top plate (hereinafter referred to as "Any Place"). With these induction ranges, an object can be inductively heated regardless of its size or location within an area containing multiple heating coils.

[0006] Induction ranges typically include a heating coil wound around a copper wire. However, to improve productivity, the heating coil must be printed onto a substrate. Because the heating coil in an induction range must be capable of conducting high currents, the manufacturing of the printed heating coil requires precise design of the pattern's thickness, width, and layer thickness.

[0007] An induction heating device according to one embodiment of the present disclosure may include an inverter circuit for driving a heating coil. An induction heating device according to one embodiment of the present disclosure may include a coil substrate including a plurality of pattern layers on which a heating coil is printed to form a coil pattern. According to one embodiment of the present disclosure, the coil patterns formed on each of the plurality of pattern layers are electrically connected, and a first end of the coil pattern may be connected to an input terminal, and a second end of the coil pattern may be connected to an output terminal. According to one embodiment of the present disclosure, at least one of the coil patterns is branched in parallel at a branch point located between the input terminal and the output terminal, and is joined at a joining point located between the branch point and the output terminal.

[0008] In an induction heating device according to one embodiment of the present disclosure, a first-layer coil pattern of a plurality of pattern layers can be electrically connected to a second-layer coil pattern of a plurality of pattern layers through a conductor formed on an inner periphery of the first-layer coil pattern.

[0009] In an induction heating device according to one embodiment of the present disclosure, a two-layer coil pattern of multiple pattern layers can be electrically connected to a three-layer coil pattern through a conductor formed on the outer periphery of the two-layer coil pattern.

[0010] In an induction heating device according to one embodiment of the present disclosure, the conductor may include a via hole vertically penetrating at least one of a plurality of pattern layers.

[0011] According to one embodiment of the present disclosure, the lengths of each of two or more branch paths branching in parallel at a branch point and joining at a joining point are equal within a difference of 5% or less.

[0012] The lengths of each of the two or more branch paths according to one embodiment of the present disclosure are equal within a difference of 1% or less when the frequency of the current flowing in the coil pattern is 50 kHz or more.

[0013] In an induction heating device according to one embodiment of the present disclosure, when a coil pattern formed in a plurality of pattern layers branches and branch paths are generated, a first branch path, a second branch path, ..., and an n-th branch path (n is a natural number greater than or equal to 2) are arranged from the inner circumference of a first-layer coil pattern, and a first branch path, a second branch path, ..., and an n-th branch path can be arranged from the outer circumference of a second-layer coil pattern.

[0014] In an induction heating device according to one embodiment of the present disclosure, the coil substrate may include an adjustment path installed on an inner or outer periphery of a first-layer coil pattern to adjust the path length of at least one of a first branch path, a second branch path, ..., and an n-th branch path.

[0015] A pattern layer including at least one coil pattern branched in parallel at a branch point of an induction heating device according to one embodiment of the present disclosure may be a pattern layer excluding the uppermost layer and the lowermost layer among a plurality of pattern layers of a coil substrate.

[0016] In an induction heating device according to one embodiment of the present disclosure, the uppermost layer, which does not include a branch point, may include an input terminal or an output terminal. In one embodiment of the present disclosure, the lowermost layer, which does not include a junction point, may include an output terminal or an input terminal.

[0017] In an induction heating device according to one embodiment of the present disclosure, a first coil pattern among coil patterns formed in a plurality of pattern layers may be branched in a first layer among the plurality of pattern layers, and a second coil pattern may be branched in a second layer among the plurality of pattern layers.

[0018] In an induction heating device according to one embodiment of the present disclosure, a branch point where at least one of the coil patterns branches in parallel may be a point where the AC resistance of the coil substrate is relatively large compared to a location where another coil pattern is located.

[0019] In an induction heating device according to one embodiment of the present disclosure, at least one coil pattern may be branched in parallel at a plurality of branch points located between an input terminal and an output terminal, as many as the number of branch points, and may be joined at a plurality of joining points located between the input terminal and the output terminal, as many as the number of joining points.

[0020] In an induction heating device according to one embodiment of the present disclosure, coil patterns of each layer including a plurality of pattern layers may be electrically connected to each other in series.

[0021] In an induction heating device according to one embodiment of the present disclosure, the coil patterns of each layer including a plurality of pattern layers may be electrically connected in series or in parallel with each other.

[0022] FIG. 1a is a drawing for explaining an induction heating device according to one embodiment of the present disclosure.

[0023] FIG. 1b is a drawing showing an anyplace induction heating device according to one embodiment of the present disclosure.

[0024] FIG. 1c is a drawing showing a heating coil in an anyplace induction heating device according to one embodiment of the present disclosure.

[0025] FIG. 1d is a circuit diagram of an induction heating device including an inverter circuit for operating a plurality of heating coils according to one embodiment of the present disclosure.

[0026] FIG. 2 is a drawing illustrating a laminated structure of a coil substrate according to one embodiment of the present disclosure.

[0027] FIG. 3 is a plan view illustrating the configuration of a coil substrate according to one embodiment of the present disclosure.

[0028] FIG. 4 is a diagram illustrating wiring of a coil substrate according to one embodiment of the present disclosure.

[0029] FIG. 5 is a drawing showing a modified example of wiring of a coil substrate according to one embodiment of the present disclosure.

[0030] FIG. 6 is a drawing showing a modified example of wiring of a coil substrate according to one embodiment of the present disclosure.

[0031] FIG. 7 is a diagram illustrating a modified example of wiring of a coil substrate including multiple branches and junctions according to one embodiment of the present disclosure.

[0032] FIG. 8 is a cross-sectional view showing interlayer connections of a coil substrate according to one embodiment of the present disclosure.

[0033] Figure 9 is a block diagram of an induction heating device according to one embodiment of the present disclosure.

[0034] The terms used in this disclosure will be briefly explained, and one embodiment of the present disclosure will be specifically described.

[0035] The terms used in this disclosure are selected from widely used, current terms, taking into account the functions of one embodiment of the disclosure. However, these terms may vary depending on the intentions of those skilled in the art, precedents, the emergence of new technologies, etc. Furthermore, in certain cases, terms may be arbitrarily selected by the applicant, and in such cases, their meanings will be described in detail in the description of the relevant embodiments of the disclosure. Therefore, the terms used in this disclosure should not be defined simply as names of terms, but rather based on the meanings of the terms and the overall content of the disclosure.

[0036] In this disclosure, the expression “at least one of a, b or c” may refer to “a”, “b”, “c”, “a and b”, “a and c”, “b and c”, “all of a, b and c”, or variations thereof.

[0037] Throughout this disclosure, when a part is said to "include" a certain component, this does not mean that other components are excluded, but rather that other components may be included, unless otherwise specifically stated. Furthermore, terms such as "part," "module," etc., used in this disclosure refer to a unit that processes at least one function or operation, and "part" and "module" may be implemented as hardware or software, or as a combination of hardware and software.

[0038] Below, with reference to the attached drawings, embodiments of the present disclosure are described in detail so that those skilled in the art can easily implement the present disclosure. However, one embodiment of the present disclosure may be implemented in various different forms and is not limited to the embodiments described herein. In addition, in the drawings, parts irrelevant to the description are omitted to clearly describe one embodiment of the present disclosure, and similar parts are designated with similar drawing reference numerals throughout the present disclosure.

[0039] Induction heating devices heat a cooking vessel by inducing a magnetic field in the heating coil. This induced magnetic field then causes eddy currents to flow in the cooking vessel, thereby heating the vessel. When the heating coil is printed on a printed circuit board (PCB), assembly becomes simpler and the durability of the induction heating device increases. However, when the heating coil is printed on a circuit board (PCB), a large current flows through the heating coil, which can cause the circuit board to overheat. Furthermore, when multiple heating coil pattern layers are formed, insulation must also be properly designed.

[0040] Accordingly, according to one embodiment of the present disclosure, an induction heating device is disclosed that includes a heating coil substrate including a plurality of heating coil pattern layers. In the present disclosure, the substrate (board) may include a printed circuit board (PCB) on which a patterned circuit is printed. When a plurality of heating coil pattern layers are laminated, an insulating layer may be included therebetween.

[0041] Conventional induction heating devices inductively heat the object by applying current to a heating coil formed on a printed circuit board, thereby generating eddy currents on the surface of the object. In this type of induction heating device, there is a need to apply high-frequency current to the printed heating coil to improve heating efficiency and miniaturize the coil.

[0042] However, when a high-frequency current is applied to the coil, the magnetic flux is concentrated on the inner or outer part of the coil, which causes the proximity effect, which increases the AC resistance, and as a result, the loss in the inner or outer part of the coil increases, and the amount of heat generated due to the loss may increase.

[0043] In addition, since printed heating coils are more difficult to dissipate heat than coiled heating coils, if heat is generated in the inner circumference due to, for example, high-frequency current, there is a risk that the inner circumference may become overheated, leading to a failure.

[0044] This phenomenon also occurs when a high-frequency current is applied to an electromagnetic induction coil used for non-contact power supply.

[0045] Hereinafter, one embodiment of an electromagnetic induction coil according to the present disclosure will be described with reference to the drawings.

[0046] The induction heating device (2000) according to the present embodiment inductively heats a cooking object, such as a cooking pot, placed on a top plate (1), and can be configured so that the heating object can be freely placed anywhere on the top plate and heated. An induction heating device that can heat the heating object no matter where it is placed on the top plate is also called an any-place induction heating device.

[0047] FIG. 1a is a drawing for explaining an induction heating device according to one embodiment of the present disclosure.

[0048] Referring to FIG. 1A, an induction heating device (2000) according to one embodiment of the present disclosure may include a plurality of burners (201, 202, 203). Hereinafter, the induction heating device (2000) may be expressed as an induction heating device, an induction heating device, an induction cooking device, or simply a heating device. Not all of the components illustrated in FIG. 1A are essential components. The induction heating device (2000) may be implemented with more components than the illustrated components, or may be implemented with fewer components.

[0049] The cooking vessel (101) as a heated object may be a device for heating the contents inside the cooking vessel (101). The contents inside the cooking vessel (101) may be liquids such as water, tea, coffee, soup, juice, wine, oil, etc., or solids such as butter, meat, vegetables, bread, rice, etc., but are not limited thereto.

[0050] According to one embodiment of the present disclosure, the cooking vessel (101) can wirelessly receive power from an induction heating device (2000) using electromagnetic induction. Therefore, the cooking vessel (101) according to one embodiment of the present disclosure may not include a power cord connected to a power outlet.

[0051] According to one embodiment of the present disclosure, the type of cooking vessel (101) that wirelessly receives power from the induction heating device (2000) may vary. The cooking vessel (101) may be a general induction heating (IH) vessel (hereinafter, IH vessel) containing a magnetic material. The cooking vessel (101) may have a magnetic field induced in the vessel (IH metal) itself.

[0052] The cooking vessel (101) may be a general IH vessel, such as a pot, a frying pan, or a steamer. The cooking vessel (101) may include a cooker device. The cooker device may be a device into which a general IH vessel may be inserted or removed. In one embodiment, the cooker device may be a device capable of automatically cooking contents according to a recipe. The cooker device may be referred to as a pot, a rice cooker, or a steamer depending on its use. For example, if an inner pot for cooking rice is inserted into the cooker device, the cooker device may be referred to as a rice cooker. Hereinafter, the cooker device may be defined as a smart pot (or smart pot).

[0053] According to one embodiment of the present disclosure, when the cooking vessel (101) includes a communication interface, the cooking vessel (101) can communicate with the induction heating device (2000). The communication interface may include a short-range communication unit, a long-range communication unit, etc. The short-range wireless communication interface may include, but is not limited to, a Bluetooth communication unit, a BLE (Bluetooth Low Energy) communication unit, an NFC (Near Field Communication interface), a WLAN (Wi-Fi) communication unit, a Zigbee communication unit, an IrDA (Infrared Data Association) communication unit, a WFD (Wi-Fi Direct) communication unit, an UWB (ultra wideband) communication unit, an ANT+ communication unit, etc. When the cooking vessel (101) is remotely controlled by a server in an IoT (Internet of Things) environment, the long-range communication unit may be used to communicate with a server (not shown). The telecommunications unit may include the Internet, a computer network (e.g., a LAN or WAN), and a mobile communication unit. The mobile communication unit may include, but is not limited to, a 3G module, a 4G module, a 5G module, an LTE module, an NB-IoT module, an LTE-M module, and the like.

[0054] According to one embodiment of the present disclosure, the cooking vessel (101) can transmit information to a server (not shown) via the induction heating device (2000). For example, the cooking vessel (101) can transmit information obtained from the cooking vessel (101) (e.g., temperature information of the contents, etc.) to the induction heating device (2000) via short-range wireless communication (e.g., Bluetooth, BLE, etc.). At this time, the induction heating device (2000) can transmit the information obtained from the cooking vessel (101) to the server by connecting to the server using a WLAN (Wi-Fi) communication unit or a long-distance communication unit (e.g., the Internet). Meanwhile, the server can provide the information obtained from the cooking vessel (101) received from the induction heating device (2000) to a user via a mobile device (not shown) connected to the server. According to one embodiment of the present disclosure, the induction heating device (2000) may directly transmit information obtained from the cooking vessel (101) to the user's mobile terminal via D2D (device to device) communication (e.g., WFD (Wi-Fi Direct) communication or BLE communication). According to one embodiment of the present disclosure, the cooking vessel (101) may directly transmit information obtained from the cooking vessel (101) (temperature information of the contents, or material information of the cooking vessel (101)) to the controller (not shown) of the induction heating device (2000) via short-range wireless communication (e.g., Bluetooth, BLE, etc.) or D2D communication.

[0055] Meanwhile, according to one embodiment of the present disclosure, the cooking vessel (101) may directly transmit information of the cooking vessel (101) (e.g., temperature information of the contents, etc.) to a server via a communication interface (e.g., WLAN (Wi-Fi) communication unit). In addition, the cooking vessel (101) may directly transmit information obtained from the cooking vessel (101) (e.g., temperature information of the contents, material information of the cooking vessel, etc.) to a user's mobile terminal via short-range wireless communication (e.g., Bluetooth, BLE, etc.) or D2D (device to device) communication.

[0056] An induction heating device (2000) according to one embodiment of the present disclosure may be a device that wirelessly transmits power to a cooking vessel (101) positioned on a top plate (1) of the induction heating device (2000) using electromagnetic induction. The induction heating device (2000) may include a working coil that generates a magnetic field for inductively heating the cooking vessel (101). The working coil is a coil that forms a magnetic field through an electric current, and may also be referred to as a heating coil throughout the present disclosure.

[0057] Generating a magnetic field by a heating coil may include transmitting power by utilizing a magnetic field induced in an IH metal (e.g., iron component) through magnetic induction. For example, an induction heating device (2000) may generate eddy currents in a cooking vessel (101) by flowing a current through a heating coil to form a magnetic field.

[0058] According to one embodiment of the present disclosure, the induction heating device (2000) may include a plurality of heating coils. For example, if the top plate (1) of the induction heating device (2000) includes a plurality of cooking zones, the induction heating device (2000) may include a plurality of heating coils corresponding to each of the plurality of cooking zones. In addition, the induction heating device (2000) may include a high-power cooking zone in which a first heating coil is provided on the inside and a second heating coil is provided on the outside. The high-power cooking zone may include two or more heating coils.

[0059] The top plate (1) of the induction heating device (2000) according to one embodiment of the present disclosure may be made of reinforced glass, such as ceramic glass, so as not to be easily broken. In addition, the top plate (1) of the induction heating device (2000) may include a guide mark to guide the cooking zone where the cooking vessel (101) should be positioned.

[0060] An induction heating device (2000) according to one embodiment of the present disclosure can detect that a cooking vessel (101) including a magnetic body is placed on a top plate (1). For example, the induction heating device (2000) can detect that the cooking vessel (101) is positioned on the top plate (1) of the induction heating device (2000) based on a change in the current value (inductance) of a heating coil due to the approach of the cooking vessel (101).

[0061] According to one embodiment of the present disclosure, the induction heating device (2000) may include a communication interface for communicating with an external device. For example, the induction heating device (2000) may communicate with a cooking vessel (101), a user's mobile device, or a server through the communication interface. The communication interface may include a short-range communication unit (e.g., an NFC communication unit, a Bluetooth communication unit, a BLE communication unit, etc.), a mobile communication unit, etc.

[0062] According to one embodiment of the present disclosure, the induction heating device (2000) can detect a cooking vessel (101) positioned on the top plate (1) through a communication interface. For example, the induction heating device (2000) can detect the cooking vessel (101) by receiving a packet transmitted from the cooking vessel (101) positioned on the top plate (1) using short-range wireless communication (e.g., BLE mesh network, Bluetooth).

[0063] According to one embodiment of the present disclosure, the induction heating device (2000) can detect whether the cooking vessel (101) is placed on the top plate (1) of the induction heating device (2000) through a vessel detection coil (vessel detection sensor) even if the cooking vessel (101) does not have a communication interface.

[0064] According to one embodiment of the present disclosure, the induction heating device (2000) can display information related to the cooking vessel (101) through a user interface. For example, when the cooking vessel (101) is detected, the induction heating device (2000) can display identification information of the cooking vessel (101) and location information of the cooking vessel (101) on a display (2411) included in the user interface.

[0065] Referring to FIG. 1A, when a user places a cooking vessel (101) (e.g., a pot) on the top plate (1) of an induction heating device (2000), the induction heating device (2000) can provide the user with identification information of the cooking vessel (101) (e.g., a pot) and location information of the cooking vessel (101) (e.g., located on the left rear burner) on a display (2411) as an output interface.

[0066] FIG. 1b is a drawing showing an anyplace induction heating device according to one embodiment of the present disclosure.

[0067] An induction heating device (2000), as illustrated in Fig. 1b, comprises a top plate (1) on which a material to be heated is placed, a plurality of heating coils (2) for heating the material to be heated, an inverter circuit (3) for supplying alternating current to the heating coils (2), and a controller (4) for controlling the inverter circuit (3).

[0068] The top plate (1) has a flat surface on which a heated material is placed on the outer surface, and the top plate (1) can be made of an electrical insulating material such as glass or ceramic, for example.

[0069] A heating coil (2) is arranged on the back (lower side) of the top plate (1). As illustrated in Fig. 1b, a plurality of heating coils (2) can be arranged to form a two-dimensional array (vertical and horizontal matrix). When current flows through this heating coil (2), a magnetic flux directed toward the top plate (1) is generated, and an eddy current is generated on the surface of the object to be heated placed on the top plate (1), so that the object to be heated can be inductively heated.

[0070] The plurality of heating coils (2) are thin coils in the form of sheets installed on a substrate, and specifically, copper foil is printed on a printed substrate (coil substrate (20)) made of photoresist or the like. Here, each of the plurality of heating coils (2) is illustrated as having the same shape and size, but the shape and size of each of the plurality of heating coils (2) may be appropriately changed. In addition, the specific configuration of the coil substrate (20) will be described later.

[0071] The inverter circuit (3) is a circuit that converts the AC voltage supplied from the power source into a driving frequency and outputs it to a plurality of heating coils (2). The inverter circuit (3) is a full bridge type using a switching element, but a half bridge type may also be used. The inverter circuit (3) may use an IGBT (insulated gate bipolar mode transistor) or FET (field effect transistor), but is not limited thereto.

[0072] The controller (4) may include a CPU, memory, input means, etc., and functionally, the CPU or its peripheral devices can cooperate to control the inverter circuit (3) according to a program stored in the memory.

[0073] FIG. 1c is a drawing showing a heating coil in an anyplace induction heating device according to one embodiment of the present disclosure.

[0074] According to Fig. 1c, the heating coil (2) of the induction heating device (2000) is made of a Litz wire wound in a circular shape and densely arranged under the top plate (1) of the induction heating device (2000) so that there is no heating gap no matter where the cooking container (101) is placed. The induction heating device (2000) as shown in Fig. 1c is the any-place induction heating device described above. In the any-place induction heating device as shown in Fig. 1c, the heating coil (2) is arranged so that there is no dead zone between the plurality of heating coils. In addition, at least one container detection coil may also be arranged at the location where the heating coil (2) is arranged. According to one embodiment, the container detection coil needs to be arranged as close to the top plate (1) as possible, and therefore, it may be arranged on the uppermost layer among the plurality of pattern layers included in the coil substrate (20). In one embodiment, a temperature sensor (2600) for sensing the temperature of a cooking vessel (101) may be placed in the center of the heating coil (2). The temperature sensor (2600) according to one embodiment of the present disclosure may be placed in a hole that vertically penetrates the coil substrate (20) on which the heating coil (2) is printed.

[0075] FIG. 1D is a circuit diagram of an induction heating device including an inverter circuit for operating a plurality of heating coils according to an embodiment of the present disclosure. Referring to FIG. 1D, an input power source (2211) is an AC power source. The AC voltage of the input power source (2211) may be supplied to a rectifier circuit (2112) through an EMI filter (2111). The rectifier circuit (2112) may use a diode as a component for converting the AC voltage into a DC voltage. The component of the rectifier circuit (2112) may be a diode, but other types of switching components capable of switching control, such as a thyristor or an IGBT, may also be used. When the AC voltage is converted into a DC voltage through the rectifier circuit (2112), the DC voltage may be smoothed by a DC link capacitor (2117_1, 2117_2).

[0076] In Fig. 1d, two resonant circuits are illustrated assuming a case where there are two heating coils (2_1, 2_2). However, if there are three craters and three heating coils are required, additional resonant circuits may be added. In addition, the circuit according to Fig. 1d may be extended to a case where there are three or more heating coils.

[0077] The DC voltage smoothed by the DC link capacitor (2117_1) generates a magnetic field in the first heating coil (2_1) by resonance between the first heating coil (2_1) and the resonant capacitor 1 (2114_1) and the resonant capacitor 2 (2114_2) through the switching operation of the two switch elements SW1 (2113_1) and SW2 (2113_2). The magnetic field generated in the first heating coil (2_1) generates an eddy current in the cooking container placed on the top of the first heating coil (2_1), thereby heating the contents of the cooking container. CT1 (2115_1) is a current sensor for detecting the current flowing in the first heating coil (2_1).

[0078] Likewise, the DC voltage smoothed by the DC link capacitor (2117_2) at the bottom generates a magnetic field in the second heating coil (2_2) by resonance between the second heating coil (2_2) and the resonance capacitor 3 (2114_3) and the resonance capacitor 4 (2114_4) through the switching operation of the two switch elements SW3 (2113_3) and SW4 (2113_4). The magnetic field generated in the second heating coil (2_2) generates an eddy current in the cooking container placed on the top of the second heating coil (2_2), thereby heating the contents of the cooking container. CT2 (2115_2) is a current sensor for detecting the current flowing in the second heating coil (2_2).

[0079] FIG. 2 is a drawing illustrating a laminated structure of a coil substrate according to one embodiment of the present disclosure.

[0080] As shown in Fig. 2, the coil substrate (20) has an input terminal (21) into which AC power is input from the inverter circuit (3), an output terminal (22) connected to a resonant capacitor, etc., and a current path pattern (L) of multiple lines connecting the input terminals (21) and the output terminals (22).

[0081] The coil substrate (20) is a printed circuit board formed by laminating a plurality of pattern layers (here, four layers) on which coil patterns (CP) are formed, as illustrated in FIGS. 2 and 3. Of course, this is only one embodiment, and the number of pattern layers may be greater than this. As illustrated in FIG. 2, the heating coil (2) may include a plurality of coil patterns (CP) that are formed to overlap on the same axis. In addition, according to one embodiment of the present disclosure, the coil patterns (CP) do not all need to overlap on the same axis, and may overlap in an offset manner.

[0082] Additionally, each pattern layer can be insulated by an insulating material installed between layers, and can be electrically connected by a conductor (23) (through hole) installed on the inner and / or outer periphery of the coil pattern (CP).

[0083] In this disclosure, the laminated multiple pattern layers are referred to as the 1st layer, the 2nd layer, the 3rd layer, and the 4th layer in order of proximity to the top plate (1).

[0084] In another embodiment of the present disclosure, four pattern layers are sequentially connected from the first to the fourth layers, as illustrated in Fig. 2. An input terminal (21) is installed on the outer periphery of the first-layer coil pattern (CP), and an output terminal (22) is installed on the outer periphery of the fourth-layer coil pattern (CP).

[0085] The pattern layer is divided into two types: the first pattern layer (PL1) and the second pattern layer (PL2).

[0086] The first pattern layer (PL1) is connected to another pattern layer at the inner periphery of the coil pattern (CP). The second pattern layer (PL2) is connected to another pattern layer at the outer periphery of the coil pattern (CP).

[0087] According to one embodiment of the present disclosure, the first and third layers are configured to be first pattern layers (PL1), and the second and fourth layers are configured to be second pattern layers (PL2).

[0088] A first layer (third layer) coil pattern (CP), which is a first pattern layer (PL1), and a second layer (fourth layer) coil pattern (CP), which is a second pattern layer (PL2) connected to the output terminal side of the first layer (third layer), can be connected in series through a conductor (23a) formed on the inner periphery of each coil pattern (CP). According to one embodiment of the present disclosure, when included in a printed circuit board, the conductor (23a) can include a through hole or via hole that vertically penetrates at least one of a plurality of pattern layers.

[0089] In addition, the second pattern layer (PL2), which is a two-layer coil pattern (CP), and the first pattern layer (PL1), which is a three-layer coil pattern (CP) connected to the second-layer output terminal side, are connected in series through a conductor (23b) formed on the outer periphery of each coil pattern (CP). According to one embodiment of the present disclosure, the conductor (23b) may be a through hole or a via hole included in a printed circuit board.

[0090] As illustrated in Fig. 2, the current path pattern (L) may be connected in series with the coil pattern (CP) of each pattern layer via a conductor (23). In addition, in Fig. 2, the current path pattern (L) of multiple lines may be integrated into one line, but is not limited thereto. In other words, the current path pattern (L) of multiple lines may be multiple lines.

[0091] FIG. 3 is a plan view illustrating the configuration of a coil substrate according to one embodiment of the present disclosure.

[0092] The coil pattern (CP) may be formed in multiple parallel lines on each pattern layer, as illustrated in FIG. 3. The coil pattern (CP) according to one embodiment of the present disclosure may have a spiral shape. A plurality of spiral shapes may be rotated about a common center without overlapping each other. In addition, as illustrated in FIG. 2, the coil pattern (CP) may be formed of a plurality of coil elements that form a roughly rectangular shape when viewed from above, or may be formed of a plurality of coil elements that form a circle when viewed from above, and the shapes of the coil elements are not limited thereto.

[0093] The number of turns of the coil pattern (CP) according to one embodiment of the present disclosure is 7, but this number of turns may be appropriately changed according to the specifications of the induction heating device (2000).

[0094] According to one embodiment of the present disclosure, a current path pattern (L), as illustrated in FIGS. 3 and 4, may branch in part or in whole from an input terminal (21) to an output terminal (22), and may join at a predetermined point (joining point (25)) between the branching point (24) and the output terminal (22). In addition, among the entire paths of the current path pattern (L), the path from the branching point (24) to the joining point (25) is referred to as a branching path, and the other paths are referred to as joining paths.

[0095] According to one embodiment of the present disclosure, a branch point (24) may be provided in the first layer (the first pattern layer (PL1)) of the four pattern layers of the coil substrate (20), and a joining point (25) may be provided in the fourth layer (the second pattern layer (PL2)). Hereinafter, the branch point (24), the joining point (25), the branch path, and the joining path will be described in detail.

[0096] According to one embodiment of the present disclosure, the branch point (24) and the junction point (25) may be installed in the middle portion between the inner and outer periphery of the coil pattern (CP) of the first layer (the first pattern layer (PL1)) or the fourth layer (the second pattern layer (PL2)), respectively. Of course, this is only one embodiment, and the branch point (24) and the junction point (25) may be arranged in other pattern layers.

[0097] Here, the middle part refers to the middle part of the spiral shape of the coil pattern (CP) of the pattern layer, and may be, for example, a turn other than the innermost or outermost among all turns of the coil pattern (CP). For example, in the case of a coil pattern (CP) of 10 turns, the middle part may be located 4 to 6 turns from the outer side. In addition, the positions of the middle parts in the first pattern layer (PL1) and the second pattern layer (PL2) may be different from each other.

[0098] As a coil pattern according to one embodiment of the present disclosure, a current path pattern (L) is formed by five parallel branch paths (1a, 1b, ..., 1e) at a branch point (24), as illustrated in FIGS. 3 and 4. Each branch path is branched into two paths, and a total of ten branch paths (1a1, 1a2, 1b1, 1b2, ..., 1e2) are formed in parallel. In FIG. 4, the third, fourth, and fifth current path patterns (L) (1c, 1d, 1e) are omitted.

[0099] According to one embodiment of the present disclosure, a joining path and a branch path are installed on the first floor, which is the top floor, and the fourth floor, which is the bottom floor, but only a branch path may be installed on the second and third floors, which are intermediate floors. However, this is only one embodiment, and the joining path may also be installed on the second and third floors.

[0100] As described above, the total number of turns of the coil pattern (CP) of each pattern layer is 7, and in each current path pattern (L) (1a, 1b, etc.) of FIG. 4, the number after -(hyphen) represents the cumulative number of turns of the coil pattern (CP) counted from the input terminal (21) side.

[0101] In addition, the branch point (24) is installed between the 3rd and 4th turns from the outer circumference of the coil pattern (CP) of the 1st floor (the 1st pattern layer (PL1)), and the joining point (25) is installed between the 3rd and 4th turns from the outer circumference of the coil pattern (CP) of the 4th floor (the 2nd pattern layer).

[0102] Each of the two branch paths installed between one branch point (24) and the junction point (25) may include a branch coil. The lengths of the branch paths are equal or substantially equal within a predetermined length. Specifically, the equal lengths of the branch paths may mean that the difference between the lengths of the two branch paths is 5% or less. In addition, when a high-frequency current of 50 kHz or more is supplied to the heating coil (2), the gap between the lengths of the two branch paths may be 1% or less. Although FIGS. 3 and 4 illustrate that one coil pattern branches into two branch paths, the configuration of the branch paths according to one embodiment of the present disclosure is not limited thereto. According to one embodiment of the present disclosure, the number of branch paths branched from one coil pattern may be three or more. For example, the number of branch paths branched from one coil pattern may be three or four. Therefore, when the number of branch paths is four, four branch paths are formed.

[0103] According to one embodiment of the present disclosure, in order to make the path lengths of each branch path equal, the arrangement of each branch path may be different in each of the plurality of stacked pattern layers. Specifically, the arrangement order of each branch path may be reversed in the first pattern layer (PL1) and the second pattern layer (PL2). For example, when each branch path is arranged in the order of 1a1, 1a2, 1b1, b2, ..., 1e2 from the outside of the coil pattern (CP) in the first pattern layer (PL1), each branch path may be arranged in the order of 1e2, 1e1, 1d2, 1d1, ..., 1a1 in the second pattern layer (PL2) from the outside of the coil pattern (CP).

[0104] In addition, according to one embodiment of the present disclosure, an adjustment path (26) for adjusting the path length of the current path pattern (L) may be installed on the inner periphery of the coil pattern (CP). According to one embodiment of the present disclosure, the adjustment path (26) may be installed on the outer periphery of the coil pattern (CP). Referring to FIG. 3, the adjustment paths (261, 262) increase the length of one branch path so that the lengths of the two branch paths are the same. The adjustment path (26) for increasing the length of the branch path may take various forms.

[0105] According to one embodiment of the present disclosure, the width of a branch path is narrower than the width of a coil pattern into which the branch paths join. Specifically, according to one embodiment of the present disclosure, the sum of the widths of a plurality of branch paths branched from a single coil pattern may be, but is not limited to, equal to the width of a single coil pattern before branching (or after joining). Specifically, the equal width may include a difference of about ±1% in the sum of the widths of the plurality of branch paths with respect to the width of the coil pattern after joining.

[0106] According to an induction heating device (2000) according to one embodiment of the present disclosure, in a part where the AC resistance of the coil pattern (CP) increases, the coil pattern can be branched in parallel to reduce the flowing current, thereby reducing coil loss and, at the same time, preventing heat from being generated biased toward the corresponding coil pattern part when the coil pattern is not branched.

[0107] Without branch paths, proximity effect can significantly impact the AC resistance within the coil pattern. Furthermore, by providing branch paths in the inner periphery of the coil pattern, where heat tends to accumulate, the loss reduction effect associated with branch paths is further enhanced, while suppressing overheating in the inner periphery.

[0108] In a heating coil (2) according to one embodiment of the present disclosure, a plurality of coil patterns may be overlapped coaxially, and since the magnetic flux density in the inner or outer periphery of the coil pattern increases as the number of overlaps increases, the branch paths branched in this way can reduce loss or suppress overheating.

[0109] In addition, since branch paths are installed in the middle layers (3rd and 4th layers) where heat is more likely to accumulate than in the top layer (1st layer) and the bottom layer (4th layer) among the multiple stacked pattern layers, overheating of the middle layers can be suppressed. Therefore, according to one embodiment of the present disclosure, a pattern layer including at least one coil pattern branched in parallel at a branch point (24) among the multiple pattern layers may be a pattern layer excluding the top layer and the bottom layer among the multiple pattern layers.

[0110] According to one embodiment of the present disclosure, since a branch point (24) is provided in a first pattern layer (PL1) (1st layer) and a joining point (25) is provided in a second pattern layer (PL2) (4th layer) arranged closer to the output terminal (22) than the first layer, a branch path can be provided biased toward the inner periphery of the coil pattern (CP). If a branch path is provided in the inner periphery, the current flowing in the inner periphery, where heat is likely to accumulate due to the proximity effect, can be reduced, thereby effectively reducing loss and suppressing overheating of the inner periphery. In addition, thermal balancing can be achieved between the inner periphery, where heat is likely to accumulate, and the outer periphery, where heat is not as likely to accumulate as the inner periphery, thereby extending the life of the heating coil.

[0111] In addition, since the path lengths of each branch path branched from one branch point (24) are equal, the impedances of each branch path can be aligned.

[0112] Since the width of the branch path is narrower than the width of the joining path, the loss of the coil due to the skin effect is reduced, and at the same time, local heating of the relevant part can be prevented when there is no branch path.

[0113] In the above example, the current path pattern (L) branched from the first pattern layer and joined at the second pattern layer. However, one embodiment of the present disclosure is not limited thereto. The current path pattern (L) may branch from the second pattern layer or may join at the first pattern layer. In a part where the AC resistance is high, the current flowing in the branched path is reduced by branching the current path pattern (L).

[0114] The coil substrate (20) according to the previous embodiment was formed by laminating four pattern layers, but the number of pattern layers to be laminated may be two layers as shown in Fig. 5, or two or more pattern layers.

[0115] In the above example, an intermediate layer (2nd layer, 3rd layer) in which no branch point (24) or junction point (25) is installed is interposed between the 1st layer (1st pattern layer (PL1)) in which a branch point (24) is installed and the 4th layer (2nd pattern layer (PL2)) in which a junction point (25) is installed. However, this intermediate layer may be composed of a plurality of pattern layers of two or more layers.

[0116] In addition, when stacking three or more pattern layers, one or more pattern layers may be installed on the input terminal side relative to the first pattern layer (PL1) where the branch point (24) is installed, or on the output terminal side relative to the second pattern layer (PL2) where the junction point (25) is installed. Accordingly, according to one embodiment of the present disclosure, a pattern layer without a branch path may be stacked. If a branch path is installed in any one of the multiple stacked pattern layers, coil loss can be reduced.

[0117] The branch path according to one embodiment of the present disclosure is installed to be located at the inner periphery of the coil pattern (CP), but may be installed to be located at the outer periphery. Since the magnetic flux is concentrated at the outer periphery of the heating coil and the AC resistance increases due to the proximity effect, by branching the current path pattern (L) in parallel at the outer periphery of the coil pattern (CP) to reduce the flowing current, the loss of the coil can be reduced, and at the same time, the portion can be prevented from being unevenly heated.

[0118] The current path pattern (L) according to one embodiment of the present disclosure is designed to have five confluence paths and ten branch paths, but the number of paths connected to the input terminal (21) and the output terminal (22) and the number of branch paths branched at the branch point (24) may be appropriately changed. Specifically, the current path pattern (L) may branch into three or more paths at the branch point (24).

[0119] According to one embodiment of the present disclosure, a plurality of current path patterns (L) branch off simultaneously in the middle of the same pattern layer and join simultaneously in another identical pattern layer. However, each current path may be independently separated or joined. For example, each current path may branch off or join in a different pattern layer. If the current path patterns (L) branch off at a point where the AC resistance of the coil substrate (20) is high, the loss of the coil can be suppressed, while preventing a portion of the coil from being biased and generating heat.

[0120] According to one embodiment of the present disclosure, each current path pattern (L) branches and joins once between the input terminal (21) and the output terminal (22), but branching and joining may be repeated multiple times between the input terminal (21) and the output terminal (22). For example, as illustrated in FIG. 6, the current path pattern (L) may branch in the middle of the first layer (the first pattern layer (PL1)), join in the middle of the second layer (the second pattern layer (PL2)), branch again in the middle of the third layer (the first pattern layer (PL1)), and join again in the fourth layer (the second pattern layer (PL2)), thereby being separated and joined twice. Of course, this is just one embodiment, and the current path pattern (L) may branch and join multiple times. According to one embodiment of the present disclosure, at least one of the coil patterns may be branched in parallel at a plurality of branch points positioned between the input terminal (21) and the output terminal (22) in a number equal to the number of branch points. In addition, at least one of the coil patterns may be joined at a plurality of joining points positioned between the input terminal (21) and the output terminal (22) in a number equal to the number of joining points.

[0121] For example, when four or more pattern layers are laminated, if the current path patterns (L) branched from each first pattern layer (PL1) are configured to join at the second pattern layer (PL2) on the output terminal (22) side (lower side) as viewed from the first pattern layer (PL1), a branch path can be installed in the inner portion of the coil pattern (CP) of each pattern layer. In this way, the current flowing in the inner portion can be reliably reduced to reduce loss, and cracking can be prevented between the inner portion where heat easily accumulates and the outer portion where heat does not accumulate as easily as the inner portion, thereby extending the life of the coil.

[0122] Additionally, a current path pattern (L) that has been branched once can be further branched. This is illustrated in Fig. 7.

[0123] FIG. 7 is a diagram illustrating a modified example of wiring of a coil substrate including multiple branches and junctions according to one embodiment of the present disclosure.

[0124] According to one embodiment of the present disclosure, for example, when four or more pattern layers are stacked, the pattern layers (2nd and 3rd layers) in the middle of the pattern layers may be more vulnerable in terms of heat generation than the uppermost layer (1st layer) or the lowermost layer (4th layer). Therefore, for example, the current path pattern (L) may be first branched at the first branch point (24_1) of the first layer among the four pattern layers, and second branched at the second branch point (24_2) of the second layer. In addition, the current path pattern (L) may be first joined at the first junction point (25_1) of the third layer among the four pattern layers, and second joined at the second junction point (25_2) of the fourth layer. Although FIG. 7 illustrates that the current path pattern (L) is branched and joined twice, this is only one embodiment, and the current path pattern (L) may be branched and joined twice or more. In addition, although the multiple pattern layers are illustrated as 4 layers in FIG. 7, the number of layers of the multiple pattern layers may be 4 or more.

[0125] According to one embodiment of the present disclosure, the input terminal (21) is installed on the first floor on the top plate (1) side, and the output terminal (22) is installed on the fourth floor of the lowest floor, but the arrangement of the input terminal (21) and the output terminal (22) may be reversed.

[0126] According to one embodiment of the present disclosure, the four-layer pattern layer is connected in the order of 1st layer -> 2nd layer -> 3rd layer -> 4th layer from the 1st layer to the 4th layer in order of proximity to the top plate (1). According to one embodiment, the connection order of each pattern layer may be appropriately changed. Specifically, the pattern layers may be connected in the order of 1st layer -> 3rd layer -> 2nd layer -> 4th layer between the input terminal (21) and the output terminal (22). In this case, the 1st and 2nd layers become the first pattern layer (PL1), and the 3rd and 4th layers become the second pattern layer (PL2).

[0127] A coil substrate according to one embodiment of the present disclosure can be used in a non-contact power supply device.

[0128] FIG. 8 is a cross-sectional view showing interlayer connections of a coil substrate according to one embodiment of the present disclosure.

[0129] FIG. 8 is a cross-sectional view illustrating interlayer connections in an eight-layer coil substrate (20) according to one embodiment of the present disclosure. Referring to FIG. 8, the coil substrate (20) may be a PCB substrate formed by stacking four or more pattern layers (PL) on which coil patterns (CP) are formed. An insulating layer formed by stacking two or more prepreg insulating layers may be included between the pattern layers.

[0130] According to one embodiment of the present disclosure, FIG. 8 illustrates a coil substrate (20) formed by stacking a plurality of pattern layers (first to eighth layers) of eight layers. According to one embodiment, the coil substrate (20) includes four layers of coil patterns (11, 12, 13, 14) and another four layers of coil patterns (15, 16, 17, 18). In one embodiment, each of the four layers of coil patterns (11, 12, 13, 14) may have four coil patterns (CP) connected in series. The four layers of coil patterns (11, 12, 13, 14) may be connected to each other through 2c through-holes (TH) or via-holes. According to one embodiment, the coil patterns (11, 12, 13, 14) may be connected in parallel through through-holes or via-holes.

[0131] In Fig. 8, let us call each pattern layer of the plurality of pattern layers (11, 12, ..., 18) from the top a 1st layer coil pattern (11), a 2nd layer coil pattern (12), a 3rd layer coil pattern (13), a 4th layer coil pattern (14), a 5th layer coil pattern (15), a 6th layer coil pattern (16), a 7th layer coil pattern (17), and an 8th layer coil pattern (18).

[0132] As illustrated in FIG. 8, the 1st layer coil pattern (11) can be connected in series with the 8th layer coil pattern (18) formed on the 8th layer through a 2d through hole. The 2nd layer coil pattern (12) can be connected in series with the 7th layer coil pattern (17) formed on the 7th layer through a 2d through hole. The 3rd layer coil pattern (13) can be connected in series with the 6th layer coil pattern (16) through a 2d through hole. The 4th layer coil pattern (14) can be connected in series with the 5th layer coil pattern (15) through a 2d through hole.

[0133] In this way, the plurality of upper pattern layers (11, 12, 13, 14) illustrated in Fig. 8 have different combinations of pattern layers that are connected in series. When four pattern layers (11, 12, 13, 14) are connected in parallel, the coil patterns (CP) formed on different pattern layers can be connected.

[0134] In addition, in the coil substrate (20) according to one embodiment of the present disclosure, the coil patterns (CP) can be connected so that the input terminal (21) is on the uppermost layer among the plurality of pattern layers, and the output terminal (22) is on the lowermost layer among the plurality of pattern layers. According to this configuration, when forming a plurality of pattern layers and mounting a weak electric sensor on the upper layer, it is easy to form the weak electric sensor in a thin film structure. The weak electric sensor can include a container detection coil. The multi-layer structure of the coil substrate (20) is not limited to the above-described eight-layer structure, and the number of layers of the multi-layer structure can be less or more.

[0135] Figure 9 is a block diagram of an induction heating device according to one embodiment of the present disclosure.

[0136] As illustrated in FIG. 9, an induction heating device (2000) according to one embodiment of the present disclosure may include a controller (4), an inverter unit (30), a top plate (1), and a coil substrate (20).

[0137] In an induction heating device (2000) according to one embodiment of the present disclosure, a top plate (1) is a plate on which a cooking vessel (101) is placed and is usually made of heat-resistant tempered glass. The top plate (1) may include a user interface (2400). The user interface (2400) may include an output interface (2410) such as a display and an input interface (2420) such as a touch button. In one embodiment, the actual operation of the output interface (2410) such as a display and the input interface (2420) such as a touch button may be performed under the control of a processor (2200) as described below.

[0138] The output interface (2410) is for outputting audio signals or video signals and may include a display and an audio output section, etc.

[0139] When the display and the touchpad are configured as a touch screen in a layered structure, the display can be used as an input interface (2420) in addition to an output interface (2410). The display can include at least one of a liquid crystal display, a thin film transistor-liquid crystal display, a light-emitting diode (LED), an organic light-emitting diode, a flexible display, a 3D display, and an electrophoretic display. In addition, depending on the design, the induction heating device (2000) can include two or more displays.

[0140] The audio output unit can output audio data received from the communication interface (2300) or stored in the memory (2500). In addition, the audio output unit can output audio signals related to functions performed in the induction heating device (2000). The audio output unit can include a speaker, a buzzer, etc.

[0141] According to one embodiment of the present disclosure, the output interface (2410) can display information regarding the cooking vessel (101). For example, the output interface (2410) can output a GUI (Graphical User Interface) corresponding to identification information or product type information of the cooking vessel (101). In addition, the output interface (2410) can output information regarding the current location of the cooking vessel (101) or the material of the cooking vessel (101).

[0142] The input interface (2420) is for receiving input from a user. The input interface (2420) may be at least one of a key pad, a dome switch, a touch pad (contact electrostatic capacitance type, pressure resistive film type, infrared detection type, surface ultrasonic conduction type, integral tension measurement type, piezo effect type, etc.), a jog wheel, and a jog switch, but is not limited thereto.

[0143] The input interface (2420) may include a voice recognition module. For example, the induction heating device (2000) may receive a voice signal, which is an analog signal, through a microphone, and convert the voice portion into computer-readable text using an Automatic Speech Recognition (ASR) model. The induction heating device (2000) may interpret the converted text using a Natural Language Understanding (NLU) model to obtain the user's speech intent. Here, the ASR model or the NLU model may be an artificial intelligence model. The artificial intelligence model may be processed by an artificial intelligence-dedicated processor designed with a hardware structure specialized for processing artificial intelligence models. The artificial intelligence model may be created through learning. Here, being created through learning means that a basic artificial intelligence model is learned using a plurality of learning data by a learning algorithm, thereby creating a predefined operation rule or artificial intelligence model set to perform a desired characteristic (or purpose). The artificial intelligence model may be composed of a plurality of neural network layers. Each of the multiple neural network layers has multiple weight values, and performs neural network operations through operations between the operation results of the previous layer and the multiple weight values.

[0144] Linguistic understanding is the technology of recognizing, applying, and processing human language / characters, including natural language processing, machine translation, dialog systems, question answering, and speech recognition / synthesis.

[0145] In an induction heating device (2000) according to one embodiment of the present disclosure, a coil substrate (20) may include a plurality of pattern layers, for example, a 1-layer coil pattern (11), a 2-layer coil pattern (12), ..., n-layer coil pattern (19) (n is a natural number greater than or equal to 2). The 1-layer coil pattern (11), the 2-layer coil pattern (12), ..., n-layer coil pattern (19) may include a patterned heating coil printed on a PCB. The coil substrate (20) may have a structure in which the 1-layer coil pattern (11), the 2-layer coil pattern (12), ..., n-layer coil pattern (19) is laminated, and through this, the heating coil constitutes a plurality of heating coils (2).

[0146] A plurality of heating coils (2) patterned on a coil substrate (20) can generate a magnetic field for heating a cooking vessel (101). For example, when current is supplied to the plurality of heating coils (2), a magnetic field can be induced around the plurality of heating coils (2). When a current, i.e., an alternating current, whose magnitude and direction change over time is supplied to the plurality of heating coils (2), a magnetic field whose magnitude and direction change over time can be induced around the plurality of heating coils (2). The magnetic field around the plurality of heating coils (2) can pass through the top plate (1) made of tempered glass and can reach the cooking vessel (101) placed on the top plate (1). Due to the magnetic field whose magnitude and direction change over time, an eddy current that rotates around the magnetic field can be generated in the cooking vessel (101), and due to the eddy current, resistive heat can be generated in the cooking vessel (101). Resistance heat is heat generated in a resistor when current flows through the resistor, and is also called Joule heat. The cooking vessel (101) is heated by the electric resistance heat, and the contents inside the cooking vessel (101) can be heated.

[0147] In an induction heating device (2000) according to one embodiment of the present disclosure, the coil substrate (20) may further include a temperature sensor (2600). The temperature sensor (2600) may sense the temperature of the top plate (1) or the cooking vessel (101) placed on the top plate (1). Based on the temperature of the cooking vessel (101) sensed by the temperature sensor (2600), the processor (2200) may determine whether the cooking vessel (101) is being co-heated or overheated. In one embodiment, the temperature sensor (2600) may be installed in a hole penetrating the coil substrate (20).

[0148] The coil substrate (20) of the induction heating device (2000) according to one embodiment of the present disclosure may further include a container detection coil layer (33). In one embodiment, the container detection coil layer (33) may include a container detection coil. In one embodiment, the container detection coil may be printed on the PCB in a pattern form as a part of a first-layer coil pattern (11). The processor (2200) of the induction heating device (2000) may detect whether a cooking vessel (101) is placed on the top plate (1) of the induction heating device (2000) through the container detection coil included in the container detection coil layer (33) or the first-layer coil pattern (11).

[0149] The inverter unit (30) may include a driving unit (2110). The driving unit (2110) may receive power from an input power source and supply current to a plurality of heating coils (2) according to a driving control signal of a processor (2200). The driving unit (2110) may include, but is not limited to, an EMI (Electro Magnetic Interference) filter (2111), a rectifier circuit (2112), an inverter circuit (3), and a resonant capacitor (2114).

[0150] The EMI filter (2111) blocks high-frequency noise included in the AC voltage supplied from the input power source and can pass AC voltage and AC current of a predetermined frequency (e.g., 50 Hz or 60 Hz). A fuse and a relay for blocking overcurrent may be provided between the EMI filter (2111) and the input power source. The AC voltage from which high-frequency noise has been blocked by the EMI filter (2111) is supplied to the rectifier circuit (2112).

[0151] The rectifier circuit (2112) can convert an AC voltage into a DC voltage. For example, the rectifier circuit (2112) can convert an AC voltage whose magnitude and polarity (positive voltage or negative voltage) change over time into a DC voltage whose magnitude and polarity are constant, and can convert an AC current whose magnitude and direction (positive current or negative current) change over time into a DC current whose polarity does not change over time. The rectifier circuit (2112) can include a diode as a rectification element. For example, the rectifier circuit (2112) can include four diodes. The diodes can convert an AC voltage whose polarity changes over time into a positive voltage whose polarity is constant, and can convert an AC current whose direction changes over time into a positive current whose direction is constant. The rectifier circuit (2112) can be connected to a DC link capacitor that smoothes the rectified DC voltage.

[0152] The inverter circuit (3) may include a switching circuit that supplies or cuts off driving current to a plurality of heating coils (2). The inverter circuit (3) may generate resonance between the plurality of heating coils (2) and the resonance capacitor (2114) through the switching operation of the switching circuit. According to one embodiment, the induction heating device (2000) may include a separate driving processor in addition to the processor (2200) to generate a driving control signal provided to the switching element of the inverter circuit (3).

[0153] The inverter circuit (3) can control the current supplied to multiple heating coils (2).

[0154] In an induction heating device (2000) according to one embodiment of the present disclosure, the controller (4) may include, but is not limited to, a processor (2200), a communication interface (2300), and a memory (2500). In addition, components included in the controller (4) may be electrically connected to components included in the inverter unit (30), the top plate (1), and the coil substrate (20) via connectors or the like.

[0155] The processor (2200) of the controller (4) can determine the switching frequency (turn-on / turn-off frequency) of the switching circuit included in the inverter circuit (3) based on the output strength (power level) of the induction heating device (2000). The processor (2200) can generate a driving control signal for turning the switching circuit on / off according to the determined switching frequency. The induction heating device (2000) can include a driving processor separate from the processor (2200) to control the operation of the driving unit (2110) including the inverter circuit (3) during the operation of the processor (2200). However, this is only one embodiment, and the operation of the driving processor may be replaced by the processor (2200).

[0156] The processor (2200) is a hardware device that controls the overall operation of the induction heating device (2000). The processor (2200) may include one processor or may include multiple processors. The processor (2200) according to one embodiment of the present disclosure may be a hardware processing circuit including at least one of a Central Processing Unit (CPU), a Graphics Processing Unit (GPU), an Accelerated Processing Unit (APU), a Many Integrated Core (MIC), a Digital Signal Processor (DSP), an integrated circuit, and a Neural Processing Unit (NPU). The processor (2200) may be implemented in the form of an integrated system on a chip (SoC) including one or more electronic components. When the processor (2200) includes multiple processors, each processor may be implemented as a separate hardware (H / W). The processor (2200) may be expressed as a Microprocessor controller (MICOM), a Micro Processor unit (MPU), or a Micro Controller Unit (MCU). The processor (2200) according to one embodiment of the present disclosure is a hardware device that may be implemented as a single core processor or a multicore processor. The processor (2200) may control components of the inverter unit (30), the communication interface (2300), the user interface (2400), the memory (2500), and the coil substrate (20) by executing programs stored in the memory (2500).

[0157] According to one embodiment of the present disclosure, the induction heating device (2000) may be equipped with an artificial intelligence (AI) processor. The AI ​​processor may be manufactured in the form of a dedicated hardware chip for artificial intelligence (AI), or may be manufactured as part of an existing general-purpose processor (e.g., CPU or application processor) or a graphics-only processor (e.g., GPU) and equipped in the induction heating device (2000).

[0158] The processor (2200) can establish a short-range wireless communication channel (e.g., a BLE communication channel) with the cooking vessel (101) through the communication interface (2300) when the unique identification information of the cooking vessel (101) is stored in the memory (2500).

[0159] The communication interface (2300) of the controller (4) may include one or more components that enable communication between the induction heating device (2000) and the cooking vessel (101), the induction heating device (2000) and a server (not shown), or the induction heating device (2000) and a user terminal (not shown). For example, the communication interface (2300) may include a short-range wireless communication interface (2310) and a long-range communication unit (2320). The short-range communication unit (2310) may include, but is not limited to, a Bluetooth communication unit, a BLE (Bluetooth Low Energy) communication unit, a near field communication interface, a WLAN (Wi-Fi) communication unit, a Zigbee communication unit, an IrDA (infrared Data Association) communication unit, a WFD (Wi-Fi Direct) communication unit, an UWB (Ultra Wideband) communication unit, an ANT+ communication unit, etc. The long-range communication unit (2320) may be used to communicate with a server (not shown) when the cooking vessel (101) is remotely controlled by a server in an IoT (Internet of Things) environment. The long-range communication unit (2320) may include the Internet, a computer network (e.g., LAN or WAN), and a mobile communication unit. The mobile communication unit transmits and receives a wireless signal with at least one of a base station, an external terminal, and a server on a mobile communication network. Here, the wireless signal may include various types of data, such as voice call signals, video call signals, or text / multimedia message transmission and reception. The mobile communication unit may include, but is not limited to, a 3G module, a 4G module, an LTE module, a 5G module, a 6G module, an NB-IoT module, an LTE-M module, etc.

[0160] The memory (2500) may store a program for the operation and control of the induction heating device (2000) of the processor (2200), and may store input / output data (e.g., unique identification information of the cooking vessel (101), variable identification information of the cooking vessel (101), multiple power transmission patterns, cooking progress information of the cooking vessel (101), material information of the cooking vessel (101), etc.). The memory (2500) may store a coded command regarding a switching operation for driving the inverter circuit (3). In addition, the memory (2500) may also store an artificial intelligence model.

[0161] The memory (2500) may include at least one type of storage medium among a flash memory type, a hard disk type, a multimedia card micro type, a card type memory (e.g., SD or XD memory, etc.), a RAM (Random Access Memory), a SRAM (Static Random Access Memory), a ROM (Read-Only Memory), an EEPROM (Electrically Erasable Programmable Read-Only Memory), a PROM (Programmable Read-Only Memory), a magnetic memory, a magnetic disk, and an optical disk. In addition, the induction heating device (2000) may also operate a web storage or cloud server that performs a storage function on the Internet.

[0162] According to one embodiment of the present disclosure, a coil substrate formed by stacking a plurality of pattern layers having coil patterns formed thereon is formed by connecting the coil patterns in series and may include a plurality of lines of current path patterns connecting an input terminal and an output terminal. According to one embodiment of the present disclosure, some or all of the plurality of lines of current path patterns may be branched in parallel at a branch point from the input terminal to the output terminal. According to one embodiment of the present disclosure, some or all of the plurality of lines of current path patterns may be joined at a joining point between the branch point and the output terminal.

[0163] According to one embodiment of the present disclosure, one of the plurality of pattern layers may be either a first pattern layer that is connected to another pattern layer on the output terminal side through a conductor formed on the inner periphery of the coil pattern, or a second pattern layer that is connected to another pattern layer on the output terminal side through a conductor formed on the outer periphery of the coil pattern. According to one embodiment of the present disclosure, part or all of the current path pattern may be branched from the first pattern layer and joined in another pattern layer.

[0164] According to one embodiment of the present disclosure, the branched current path patterns can be joined in a second pattern layer.

[0165] According to one embodiment of the present disclosure, when a path from a branch point to a junction point among the entire paths of a current path pattern is a branch path, the path lengths of each branch path branched from the same current path pattern are equal within a predetermined error range.

[0166] According to one embodiment of the present disclosure, there may be a plurality of pattern layers between a first pattern layer having a branch point and a second pattern layer having a joining point.

[0167] According to one embodiment of the present disclosure, the width of the current path pattern before branching and joining may be narrower than the width of the current path pattern before branching or after joining.

[0168] An induction heating device according to one embodiment of the present disclosure may include an inverter circuit for driving a heating coil. An induction heating device according to one embodiment of the present disclosure may include a coil substrate including a plurality of pattern layers on which a heating coil is printed to form a coil pattern. According to one embodiment of the present disclosure, the coil patterns formed on each of the plurality of pattern layers are electrically connected, and a first end of the coil pattern may be connected to an input terminal, and a second end of the coil pattern may be connected to an output terminal. According to one embodiment of the present disclosure, at least one of the coil patterns branches in parallel at a branch point located between the input terminal and the output terminal, and joins at a joining point located between the input terminal and the output terminal.

[0169] In an induction heating device according to one embodiment of the present disclosure, a first-layer coil pattern of a plurality of pattern layers can be electrically connected to a second-layer coil pattern of a plurality of pattern layers through a conductor formed on an inner periphery of the first-layer coil pattern.

[0170] In an induction heating device according to one embodiment of the present disclosure, a two-layer coil pattern of multiple pattern layers can be electrically connected to a three-layer coil pattern through a conductor formed on the outer periphery of the two-layer coil pattern.

[0171] In an induction heating device according to one embodiment of the present disclosure, the conductor may include a via hole vertically penetrating at least one of a plurality of pattern layers.

[0172] According to one embodiment of the present disclosure, the lengths of each of two or more branch paths branching in parallel at a branch point and joining at a joining point are equal within a difference of 5% or less.

[0173] The lengths of each of the two or more branch paths according to one embodiment of the present disclosure are equal within a difference of 1% or less when the frequency of the current flowing in the coil pattern is 50 kHz or more.

[0174] In an induction heating device according to one embodiment of the present disclosure, when a coil pattern formed in a plurality of pattern layers branches and branch paths are generated, a first branch path, a second branch path, ..., and an n-th branch path (n is a natural number greater than or equal to 2) are arranged from the inner circumference of a first-layer coil pattern, and a first branch path, a second branch path, ..., and an n-th branch path can be arranged from the outer circumference of a second-layer coil pattern.

[0175] In an induction heating device according to one embodiment of the present disclosure, the coil substrate may include an adjustment path installed on an inner or outer periphery of a first-layer coil pattern to adjust the path length of at least one of a first branch path, a second branch path, ..., and an n-th branch path.

[0176] A pattern layer including at least one coil pattern branched in parallel at a branch point of an induction heating device according to one embodiment of the present disclosure may be a pattern layer excluding the uppermost layer and the lowermost layer among a plurality of pattern layers of a coil substrate.

[0177] In an induction heating device according to one embodiment of the present disclosure, the uppermost layer, which does not include a branch point, may include an input terminal or an output terminal. In one embodiment of the present disclosure, the lowermost layer, which does not include a junction point, may include an output terminal or an input terminal.

[0178] In an induction heating device according to one embodiment of the present disclosure, a first coil pattern among coil patterns formed in a plurality of pattern layers may be branched in a first layer among the plurality of pattern layers, and a second coil pattern may be branched in a second layer among the plurality of pattern layers.

[0179] In an induction heating device according to one embodiment of the present disclosure, a branch point where at least one of the coil patterns branches in parallel may be a point where the AC resistance of the coil substrate is relatively large compared to a location where another coil pattern is located.

[0180] In an induction heating device according to one embodiment of the present disclosure, at least one coil pattern may be branched in parallel at a plurality of branch points located between an input terminal and an output terminal, as many as the number of branch points, and may be joined at a plurality of joining points located between the input terminal and the output terminal, as many as the number of joining points.

[0181] In an induction heating device according to one embodiment of the present disclosure, coil patterns of each layer including a plurality of pattern layers may be electrically connected to each other in series.

[0182] In an induction heating device according to one embodiment of the present disclosure, the coil patterns of each layer including a plurality of pattern layers may be electrically connected in series or in parallel with each other.

[0183] A coil substrate according to one embodiment of the present disclosure can be used in an induction heating device or a non-contact power supply device.

[0184] The induction heating device according to the present disclosure configured in this manner can suppress loss in the coil when high-frequency current is passed through it, while at the same time preventing a portion of the coil from being biased and generating heat.

[0185] In addition, the present disclosure is not limited to the above-described embodiments, and various modifications are possible without departing from the spirit thereof.

[0186] A method according to an embodiment of the present disclosure may be implemented in the form of program commands that can be executed through various computer means and recorded on a computer-readable medium. The computer-readable medium may include program commands, data files, data structures, etc., alone or in combination. The program commands recorded on the medium may be those specially designed and configured for the present disclosure or may be known and available to those skilled in the art of computer software. Examples of computer-readable recording media include magnetic media such as hard disks, floppy disks, and magnetic tapes, optical media such as CD-ROMs and DVDs, magneto-optical media such as floptical disks, and hardware devices specially configured to store and execute program commands, such as ROMs, RAMs, and flash memories. Examples of program commands include not only machine language codes generated by a compiler, but also high-level language codes that can be executed by a computer using an interpreter, etc.

[0187] Some embodiments of the present disclosure may also be implemented in the form of a recording medium containing computer-executable instructions, such as program modules, executed by a computer. Computer-readable media may be any available media that can be accessed by a computer, and include both volatile and nonvolatile media, removable and non-removable media. Furthermore, computer-readable media may include both computer storage media and communication media. Computer storage media includes both volatile and nonvolatile, removable and non-removable media implemented in any method or technology for storage of information, such as computer-readable instructions, data structures, program modules, or other data. Communication media typically contains computer-readable instructions, data structures, program modules, or other data in a modulated data signal, such as a carrier wave, or other transport mechanism, and includes any information delivery media. Furthermore, some embodiments of the present disclosure may also be implemented as a computer program or computer program product containing computer-executable instructions, such as a computer program that is executed by a computer.

[0188] A device-readable storage medium may be provided in the form of a non-transitory storage medium. Here, the term "non-transitory storage medium" simply means a tangible device that does not contain signals (e.g., electromagnetic waves). This term does not distinguish between cases where data is permanently stored in the storage medium and cases where data is temporarily stored. For example, a "non-transitory storage medium" may include a buffer in which data is temporarily stored.

[0189] According to one embodiment, the method according to various embodiments disclosed in the present document may be provided as included in a computer program product. The computer program product may be traded as a product between a seller and a buyer. The computer program product may be distributed in the form of a machine-readable storage medium (e.g., compact disc read-only memory (CD-ROM)), or may be distributed online (e.g., downloaded or uploaded) through an application store or directly between two user devices (e.g., smartphones). In the case of online distribution, at least a portion of the computer program product (e.g., a downloadable app) may be temporarily stored or temporarily generated in a machine-readable storage medium, such as the memory of a manufacturer's server, an application store's server, or an intermediary server.

Claims

1. Inverter circuit for driving the heating coil; and The heating coil comprises a coil substrate including a plurality of pattern layers in which the coil pattern is formed by printing, The coil patterns formed on each of the plurality of pattern layers are electrically connected, and a first end of the coil pattern is connected to an input terminal, and a second end of the coil pattern is connected to an output terminal. An induction heating device, wherein at least one of the coil patterns is branched in parallel at a branch point located between the input terminal and the output terminal, and joined at a joining point located between the branch point and the output terminal.

2. In paragraph 1, An induction heating device in which the first-layer coil pattern of the plurality of pattern layers is electrically connected to the second-layer coil pattern of the plurality of pattern layers through a conductor formed on the inner periphery of the first-layer coil pattern.

3. In paragraph 2, An induction heating device in which the two-layer coil pattern of the plurality of pattern layers is electrically connected to the three-layer coil pattern through a conductor formed on the outer periphery of the two-layer coil pattern.

4. In any one of paragraphs 2 to 3, An induction heating device, wherein the conductor comprises a via hole vertically penetrating at least one of the plurality of pattern layers.

5. In any one of paragraphs 1 to 4, An induction heating device in which the lengths of two or more branch paths branching in parallel at the branch point and joining at the junction point are equal within a difference of 5% or less.

6. In paragraph 5, An induction heating device wherein the length of each of the two or more branch paths is uniform within a difference of 1% or less when the frequency of the current flowing in the coil pattern is 50 kHz or higher.

7. In any one of paragraphs 5 to 6, An induction heating device, wherein the branch paths generated by branching the coil patterns formed on the plurality of pattern layers are arranged such that a first branch path, a second branch path, a, and an n-th branch path (n is a natural number greater than or equal to 2) are arranged from the inner circumference of the first-layer coil pattern, and the first branch path, the second branch path, a, and the n-th branch path are arranged from the outer circumference of the second-layer coil pattern.

8. In paragraph 7, An induction heating device, wherein the coil substrate includes an adjustment path installed on an inner or outer periphery of the first-layer coil pattern to adjust the path length of at least one of the first branch path, the second branch path, the nth branch path, and the nth branch path.

9. In any one of paragraphs 1 to 8, An induction heating device, wherein a pattern layer including at least one of the coil patterns branched in parallel at the branch point is a pattern layer excluding the uppermost layer and the lowermost layer among the plurality of pattern layers of the coil substrate.

10. In paragraph 9, The uppermost layer, which does not include the branch point, includes the input terminal or the output terminal, An induction heating device, wherein the lowermost layer, which does not include the above-mentioned joining point, includes the above-mentioned output terminal or the above-mentioned input terminal.

11. In paragraph 1, An induction heating device, wherein a first coil pattern among the coil patterns formed in the plurality of pattern layers branches from a first layer among the plurality of pattern layers, and a second coil pattern branches from a second layer among the plurality of pattern layers.

12. In paragraph 1, An induction heating device, wherein a branch point at which at least one of the above coil patterns branches out in parallel is a point at which the AC resistance of the coil substrate is relatively large compared to a point at which another coil pattern is located.

13. In paragraph 1, An induction heating device, wherein at least one of the coil patterns is branched in parallel at a plurality of branch points located between the input terminal and the output terminal as many times as the number of the plurality of branch points, and joins at a plurality of junction points located between the input terminal and the output terminal as many times as the number of the plurality of junction points.

14. In any one of paragraphs 1 to 13, An induction heating device in which the coil patterns of each layer included in the plurality of pattern layers are electrically connected to each other in series.

15. In any one of paragraphs 1 to 13, An induction heating device in which the coil patterns of each layer included in the plurality of pattern layers are electrically connected in series or in parallel with each other.

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