KR102582071B1 - Magnetic sheet and wireless power receiving apparatus including the sheet - Google Patents

Abstract

The magnetic sheet of the embodiment includes at least two stacked magnetic sheet portions and an adhesive portion disposed between two surfaces of first and second magnetic sheet portions adjacent to each other among the stacked magnetic sheet portions, and the adhesive portion has a net planar shape. at least one plate having; and an adhesive disposed surrounding the at least one plate, spaced apart from the first and second magnetic sheet portions, and connected through the mesh of the at least one plate.

Description

MAGNETIC SHEET AND WIRELESS POWER RECEIVING APPARATUS INCLUDING THE SHEET}

The embodiment relates to a magnetic sheet and a wireless power reception device including the sheet.

As the Near Field Communication (NFC) function is adopted in mobile terminals such as smartphones, it is widely used as a payment method, transportation card, access card, or P2P (point to point) information exchange between mobile phones. NFC uses 13.56 MHz and is an ultra-short-range communication method that only operates at a distance of up to 20 cm, so it is very safe from hacking and is suitable as a payment method.

The NFC antenna (not shown) for implementing this NFC function is placed on the back of the battery included in the smartphone (not shown), mounted on the back of the smartphone case, or in-molded, considering its size. there is. In particular, since the smartphone battery case is made of metal, the electromagnetic field energy generated by the NFC antenna is absorbed by the battery case, which acts as a parasitic coupler. Therefore, the communication sensitivity of the NFC antenna is lowered, and as a result, the communication distance becomes very short, so electromagnetic isolation is required between the metal battery case and the NFC antenna. As such an isolation means, a magnetic sheet with a magnetic permeability of less than 1 mm in thickness is mainly used.

Meanwhile, wireless charging (i.e. wireless power transmission and reception) technology has recently been receiving great attention. Representative examples of standard methods for wireless power transmission include WPC (Wireless Power Consortium), A4WP (Alliance for Wireless Power), and PMA (Power Matters Alliance) methods, and are technically divided into magnetic induction and magnetic resonance methods. Ultimately, magnetic materials for magnetic induction or magnetic resonance are also used in the transmission and reception modules of wireless charging systems. Due to the use of these magnetic materials, there have been attempts to minimize electromagnetic energy loss by introducing magnetic sheets as electromagnetic shielding materials. Through this, efforts are continuing to improve the function and performance of transmission efficiency (wireless power transmission), which had previously relied only on coil design.

Representative magnetic sheet materials include sheets containing ferrite materials, composite sheets containing metal powder and polymer resin, metal-alloy based magnetic ribbon sheets, or metal ribbon sheets containing only metal ribbons. . Among these, sheets containing ferrite materials have good magnetic permeability, but there are thickness restrictions due to high-temperature sintering and limitations in magnetic flux density, and composite-type sheets have a problem of low magnetic permeability. On the other hand, a metal ribbon sheet can achieve high permeability and magnetic flux density with a thin thickness.

A metal ribbon refers to an amorphous or nanocrystalline metal or alloy manufactured into a very thin foil through a technique such as an atomizer. However, such metal ribbons are generally used in a laminated structure with multiple layers to obtain desired shielding properties. The energy transmitted during short-distance communication or wireless charging is in the form of a magnetic field with a frequency, so if the magnetic sheet is made up of a single lump instead of stacking metal ribbons, the conductivity increases and eddy current loss increases exponentially. Because.

For lamination, ribbons and adhesive films with an insulating function may be arranged alternately in each layer. This adhesive film maintains the gap between the stacked metal ribbons and secures insulation and adhesive strength. However, when an adhesive film is disposed between ribbons, the overall effective permeability is lowered due to magnetic flux loss generated from the adhesive film, which causes a problem in that transmission efficiency is reduced. In addition, there is a problem that the thickness of the magnetic sheet increases when the number of stacks is increased to compensate for the effective permeability.

The embodiment provides a magnetic sheet that has a high effective permeability, improves transmission efficiency, has a uniform thickness, and maintains adhesion without deterioration, and a wireless power receiving device including the sheet.

A magnetic sheet according to one embodiment includes at least two stacked magnetic sheet portions; and an adhesive portion disposed between two surfaces of first and second magnetic sheet portions adjacent to each other among the stacked magnetic sheet portions, wherein the adhesive portion has a mesh planar shape and includes a mesh plate; And it may include an adhesive that is disposed surrounding the plate and spaced apart from the first and second magnetic sheet portions.

For example, the adhesive may include: a first adhesive layer disposed between the plate and a first side, which is one of the two sides facing each other; a second adhesive layer disposed between the plate and a second side, the other of the two facing sides; And it may include a third adhesive layer connecting the first adhesive layer and the second adhesive layer through the mesh.

For example, the plate may include a plurality of plates stacked in a vertical direction between the first surface and the second surface.

For example, at least some of the meshes of the plurality of plates may not overlap in the vertical direction.

For example, the meshes of the plurality of plates may be arranged to overlap each other at least partially in the vertical direction.

For example, at least one of the thickness, mesh shape, or mesh size of each of the plurality of plates may be the same or different from each other.

For example, the planar shape of the mesh may include at least one of a circle, an oval, or a polygon.

For example, the at least one plate may have at least one property of ductility or magnetism. The at least one plate is made of magnetic stainless steel (Fe-Cr-Al-Si), sandust (Fe-Si-Al), permalloy (Fe-Ni), Fe-Si alloy silicon copper (Fe-Cu-Si), It may include at least one of Fe-S-B(-Cu-Nb) alloy, Fe-Si-Cr-Ni alloy, Fe-Si-Cr alloy, Fe-Si-Al-Ni-Cr alloy, or ferrite.

According to another embodiment, a wireless power reception device that receives power transmitted from a wireless power transmission device includes: a substrate; A magnetic sheet disposed on the substrate; and a coil disposed on the magnetic sheet and receiving electromagnetic energy radiated from the wireless power transmission device, wherein the magnetic sheet includes at least two stacked magnetic sheet portions; and an adhesive portion disposed between two surfaces of first and second magnetic sheet portions adjacent to each other among the stacked magnetic sheet portions, wherein the adhesive portion has a mesh planar shape and includes a mesh plate; And it may include an adhesive that is disposed surrounding the plate and spaced apart from the first and second magnetic sheet portions.

A magnetic sheet according to an embodiment, a wireless power receiving device including the sheet, and a mobile device including the device can minimize the decrease in effective permeability, have improved transmission efficiency, have a thin thickness, and maintain adhesion. It has high reliability, can control the uniformity of the thickness of the adhesive part, reduces eddy current loss, and achieves uniform and predictable transmission efficiency.

Figure 1 is a conventional magnetic induction type equivalent circuit.
Figure 2 is a block diagram of a general wireless charging system.
Figure 3 is a plan view showing a portion of a wireless power reception device according to an embodiment.
Figure 4 shows a cross-sectional view of a magnetic sheet according to an embodiment.
Figure 5a shows a top view of an embodiment of an adhesive part included in a magnetic sheet;
Figure 5b shows a cross-sectional view taken along line II' shown in Figure 5a.
Figure 6 shows a plan view of another example of an adhesive part included in a magnetic sheet.
FIG. 7A shows a plan view of another example of an adhesive part included in a magnetic sheet, and FIG. 7B shows a cross-sectional view taken along line II-II' shown in FIG. 7A.
Figure 8 shows a plan view of another example of an adhesive part included in a magnetic sheet.
Figure 9a is a cross-sectional view for explaining the magnetic properties of a magnetic sheet according to an embodiment, and Figure 9b is a cross-sectional view for explaining the magnetic properties of a magnetic sheet according to a comparative example.
Figure 10 is a graph comparing the real permeability by frequency before and after forming a crack in the metal ribbon.
Figure 11 shows a top view of a magnetic sheet portion according to one embodiment.
Figure 12 shows a top view of a magnetic sheet portion according to another embodiment.
Figure 13 shows a top view of a magnetic sheet portion according to another embodiment.
Figure 14 shows a top view of a magnetic sheet portion according to another embodiment.
Figure 15 shows a top view of a magnetic sheet portion according to another embodiment.
Figure 16 shows a top view of a magnetic sheet portion according to another embodiment.

Hereinafter, the present invention will be described with reference to examples to specifically explain the present invention, and will be described in detail with reference to the accompanying drawings to aid understanding of the invention. However, the embodiments according to the present invention may be modified into various other forms, and the scope of the present invention should not be construed as being limited to the embodiments described in detail below. Embodiments of the present invention are provided to more completely explain the present invention to those skilled in the art.

Additionally, relational terms such as “first,” “second,” “upper,” and “lower” used below do not necessarily require or imply any physical or logical relationship or order between such entities or elements. In other words, it may be used only to distinguish one entity or element from another entity or element.

Hereinafter, the magnetic sheet 210 according to the embodiment and the wireless power receiving device 200 including the same will be described with reference to the attached drawings. For convenience, the magnetic sheet 210 and the wireless power receiving device 200 including the same are described using a Cartesian coordinate system (x-axis, y-axis, z-axis), but of course, they can also be described using other coordinate systems. In the Cartesian coordinate system, the x-axis, y-axis, and z-axis are orthogonal to each other, but the embodiment is not limited thereto. That is, the x-axis, y-axis, and z-axis may not be perpendicular to each other but may intersect.

Terms and abbreviations used in the embodiments may be defined as follows.

- Wireless Charging System (Wireless Power Transfer System): A general term for wireless power transmission devices and wireless power reception devices.

- Wireless Power Transfer System-Charger or transmitter: A device that provides wireless power transmission to one or more power receivers within a magnetic field area.

- Wireless Power Transfer Device or receiver: A device that receives wireless power transmitted from a wireless power transfer device within a magnetic field area.

- Charging Area: This is an area where actual wireless power transmission takes place within the magnetic field area, and the range of the area can vary depending on the size, power requirement, and operating frequency of the application product.

- S parameter (Scattering parameter): It is the ratio of input voltage to output voltage in the frequency distribution, and is the ratio of input port to output port, or the self-reflection value of each input/output port, that is, the output reflected by its own input and returned. It can mean value.

- Quality factor Q: In resonance, the value of Q means the quality of frequency selection. The higher the Q value, the better the resonance characteristics. The Q value is expressed as the ratio of the energy stored in the resonator and the energy lost.

The wireless power transmission device that transmits power to be received by the wireless power reception device 200 according to the embodiment selectively uses various types of frequency bands from low frequency (50 kHz) to high frequency (15 MHz) to transmit power. You can. Additionally, the wireless power transmission device requires support of a communication system capable of exchanging data and control signals to control the wireless charging system.

The wireless power receiving device 200 of the embodiment is used in the portable terminal industry such as mobile devices that use electronic devices that use or require batteries, the smart watch industry, the computer and laptop industry, the home appliance industry, the electric vehicle industry, and the medical device industry. , can be applied to various industrial fields such as the robot industry.

Embodiments may consider a wireless charging system capable of transmitting power to one or more devices using one or a plurality of transmitting coils provided with the device.

According to the embodiment, it is possible to solve the problem of battery shortage in mobile devices such as smartphones and laptops. For example, if you place a wireless charging pad on a table and use your smartphone or laptop on it, the battery is automatically charged and you can use it for a long time. . Additionally, by installing a wireless charging pad in public places such as cafes, airports, taxis, offices, and restaurants, it is possible to charge a variety of mobile devices regardless of the different charging terminals for each mobile device manufacturer. In addition, when wireless power transmission technology is applied to household appliances such as vacuum cleaners and fans, there is no need to search for power cables, and complicated wires in the home disappear, reducing wiring in buildings and expanding space utilization. In addition, it takes a lot of time to charge an electric vehicle with the current household power source, but if high power is transmitted through wireless power transmission technology, the charging time can be reduced. If a wireless charging facility is installed on the parking lot floor, the power cable will be connected around the electric vehicle. This can eliminate the inconvenience of having to prepare.

The magnetic sheet according to the embodiment can be applied to various fields as described above. Hereinafter, to help understand the magnetic sheet according to the embodiment, a wireless power receiving device according to the embodiment including a magnetic sheet will first be described with reference to FIGS. 1 to 3 as follows.

Figure 1 is a conventional magnetic induction type equivalent circuit.

Looking at the principles of transmitting power wirelessly, one of the principles of wireless power transmission is the magnetic induction method. The magnetic induction method is a non-contact energy transfer that generates electromotive force in the load inductor (L l ) through the magnetic flux generated when the source inductor (Ls) and the load inductor (L l) are brought close to each other and current flows through one source inductor (Ls ) . It's technology.

In the magnetic induction equivalent circuit shown in FIG. 1, the transmitter has a source voltage (Vs), a source resistance (Rs), a source capacitor (Cs) for impedance matching, and a source capacitor (Cs) for magnetic coupling with the receiver according to the power supply device. It can be implemented as a source coil (Ls), and the receiving unit includes a load resistance (R l ), which is the equivalent resistance of the receiving unit, a load capacitor (C l ) for impedance matching, and a load coil (L l ) for magnetic coupling with the transmitting unit. It can be implemented as: The degree of magnetic coupling between the source coil (Ls) and the load coil (L l ) can be expressed as mutual inductance (Msl).

In Figure 1, if the ratio of input voltage to output voltage is obtained from a magnetic induction equivalent circuit consisting of only a coil without a source capacitor (Cs) and a load capacitor (C l ) for impedance matching, and the maximum power transmission condition is found from this, the maximum power transmission The condition satisfies Equation 1 below.

According to Equation 1, maximum power transmission is possible when the ratio of the inductance of the transmission coil (Ls) and the source resistance (Rs) and the ratio of the inductance of the load coil (L l ) and the load resistance (R l ) are the same. In a wireless charging system in which only inductance exists, there is no capacitor that can compensate for reactance, so the self-reflection value of the input/output port cannot be '0' at the point where maximum power transfer occurs, and the mutual inductance (Msl) value Depending on this, power transfer efficiency can change significantly. Therefore, a source capacitor (Cs) may be added to the transmitting unit as a compensation capacitor for impedance matching, and a load capacitor (C l ) may be added to the receiving unit. For example, the compensation capacitors (Cs, Cl ) may be connected in series or parallel to each of the receiving coil (Ls) and the load coil (L l ). Additionally, for impedance matching, passive elements such as additional capacitors and inductors as well as compensation capacitors may be added to each of the transmitter and receiver.

Based on this principle of wireless power transmission, we look at a wireless charging system for transmitting power through magnetic induction or magnetic resonance.

Figure 2 is a block diagram of a general wireless charging system.

Referring to FIG. 2, the wireless charging system may include a transmitter 1000 and a receiver 2000 that wirelessly receives power from the transmitter 1000. The receiving unit 2000, one of the subsystems constituting the wireless charging system, includes a receiving coil unit 2100, a receiving matching unit 2200, a receiving AC/DC converter 2300, and a reception DC/DC converter. It may include (2400), a load unit (2500), and a receiving side communication and control unit (2600). Here, the receiver 2000 may refer to a wireless power reception device according to an embodiment.

The receiving coil unit 2100 may receive power through magnetic induction and may include one or more induction coils. And the receiving coil unit 2100 may be equipped with an antenna for near field communication. Additionally, the receiving coil unit 2100 may be the same as the transmitting coil unit (not shown), and the dimensions of the receiving antenna may vary depending on the electrical characteristics of the receiving unit 2000.

The receiving side matching unit 2200 performs impedance matching between the transmitter 1000 and the receiver 2000.

The AC/DC converter 2300 on the receiving side rectifies the AC signal output from the coil unit 2100 on the receiving side to generate a DC signal.

The receiving side DC/DC converter 2400 can adjust the level of the DC signal output from the receiving side AC/DC converter 2300 to suit the capacity of the load unit 2500.

The load unit 2500 may include a battery, display, audio output circuit, main processor, and various sensors.

The receiving-side communication and control unit 2600 may be activated by wake-up power from the transmitting-side communication and control unit (not shown), performs communication with the transmitting-side communication and control unit, and operates the subsystem of the receiving unit 2000. You can control it.

The receiving unit 2000 may be composed of a single or plural receiving unit and may wirelessly receive energy from the transmitting unit 1000. That is, by providing a plurality of receiving coil units 2100 that are independent of each other in the magnetic induction method, a plurality of target receiving units 2000 can receive power from one transmitting unit 1000. At this time, the transmitting side matching unit (not shown) of the transmitting unit 1000 may adaptively perform impedance matching between the plurality of receiving units 2000.

Additionally, if the receiving unit 2000 is comprised of a plurality of systems, they may be the same type of system or different types of systems.

Meanwhile, looking at the relationship between the signal size and frequency of the wireless charging system, in the case of magnetic induction type wireless power transmission, the AC/DC converter (not shown) on the transmitting side in the transmitter 1000 operates at 60 Hz of 100 V to 230 V. An AC signal can be received and converted to a DC signal of 10V to 20V and output, and the DC/AC converter on the transmitting side can receive a DC signal and output an AC signal of 125 kHz. And the AC/DC converter 2300 on the receiving side of the receiver 2000 can receive an AC signal of 125 kHz and convert it into a DC signal of 10 V to 20 V and output it, and the DC/DC converter 2400 on the receiving side Can output a direct current signal suitable for the load unit 2500, for example, 5 V, and transmit it to the load unit 2500.

Hereinafter, the wireless power reception device 200 according to an embodiment that performs at least some of the functions corresponding to the wireless power reception device 2000 shown in FIG. 2 will be looked at as follows.

Figure 3 is a plan view showing a portion of the wireless power reception device 200 according to an embodiment.

The wireless power receiving device 200 may include a receiving circuit (not shown), a magnetic sheet 210, and a receiving coil 220. The magnetic sheets 210 may be disposed individually or in a stacked manner on a substrate (not shown). The substrate may be made of several layers of fixing sheets, and may be bonded to the magnetic sheet 210 to fix the magnetic sheet 210.

The magnetic sheet 210 focuses electromagnetic energy radiated from a transmission coil (not shown) of the wireless power transmission device 1000.

A receiving coil 220 is stacked on the magnetic sheet 210. The receiving coil 220 may be wound on the magnetic sheet 210 in a direction parallel to the magnetic sheet 210 . For example, a receiving antenna applied to mobile devices such as smartphones may be in the form of a spiral coil with an outer diameter of less than 50 mm and an inner diameter of 20 mm or more. The receiving circuit converts electromagnetic energy received through the receiving coil 220 into electrical energy, and charges the converted electrical energy in a battery (not shown).

Although not shown, a heat dissipation layer may be further disposed between the magnetic sheet 210 and the receiving coil 220.

Meanwhile, when the wireless power receiving device 200 has a WPC function, a Near Field Communication (NFC) function, and a mobile payment function, an NFC coil 230 and a coil for mobile payment (not shown) are provided on the magnetic sheet 210. This may be further layered. The NFC coil 230 and the mobile payment coil may have a planar shape surrounding the receiving coil 220.

Additionally, each of the receiving coil 220 and the NFC coil 230 may be electrically connected to an external circuit (eg, integrated circuit) (not shown) through the terminal 240.

In FIG. 3, both the receiving coil 220 and the NFC coil 230 are shown as being disposed on one magnetic sheet 210, but this is merely an example. According to another embodiment, unlike shown in FIG. 3, a separate magnetic sheet corresponding thereto may be disposed in each area of each coil 220 and 230. In this case, the magnetic sheets corresponding to each coil may be configured to have different shielding characteristics or may be configured to have the same characteristics. In addition, in FIG. 3, the NFC coil 230 is shown surrounding the outside of the receiving coil 220, but this is also an example and a separate area is formed so that neither one of the two coils 220, 230 surrounds the other. It can be formed spaced apart from .

Hereinafter, the structure of the magnetic sheet 210 according to the embodiment and its magnetic properties 210 will be described with reference to the attached drawings.

Figure 4 shows a cross-sectional view of the magnetic sheet 210 according to an embodiment.

The magnetic sheet 210 according to one embodiment may include N magnetic sheet portions and N-1 adhesive portions. Here, N is a positive integer of 2 or more. In the case of Figure 4, the case where N=3 is shown. That is, the magnetic sheet 210 is illustrated as including first to third magnetic sheet portions (R1, R2, R3) and first and second adhesive portions (A1, A2), but the embodiment is not limited thereto. .

That is, although not shown, according to another embodiment, the magnetic sheet 210 includes two (N=2) magnetic sheet parts ((R1 and R2) or (R2 and R3)) and one adhesive part (A1). Alternatively, it may include only A2), or it may include four (N≥4) or more magnetic sheet portions and three or more adhesive portions.

Additionally, according to an embodiment, two magnetic sheet parts and one adhesive part are one minimum structural unit, and the magnetic sheet may include at least one such minimum structural unit. In the case of FIG. 4, the magnetic sheet 210 is illustrated as having two minimum structural units, but the embodiment is not limited thereto. That is, according to another embodiment, the magnetic sheet 210 may include only one minimum structural unit [(R1, A1, R2) or (R2, A2, R3)], or may include three or more minimum structural units. You may.

Additionally, in the magnetic sheet 210, the adhesive portion is disposed between two or more stacked magnetic sheet portions, so the number of adhesive portions may be one less than the number of magnetic sheet portions. For example, in the case of FIG. 4, since the number of magnetic sheet portions (R1, R2, and R3) is three, the number of adhesive portions (A1, A2) may be two.

Hereinafter, for ease of understanding, it is assumed that N is '3' and the magnetic sheet 210 according to the embodiment is described. However, the following description can be applied even when N is '2' or '4' or more. Of course.

The first to third magnetic sheet portions R1, R2, and R3 and the first and second adhesive portions A1 and A2 may be stacked and arranged to overlap in the vertical direction. Here, the vertical direction may be the thickness direction of the magnetic sheet 210, for example, the x-axis direction, but the embodiment is not limited thereto.

At least one of the first magnetic sheet portion (R1), the second magnetic sheet portion (R2), and the third magnetic sheet portion (R3) may be made of a metal-alloy based magnetic ribbon. Here, 'ribbon' is defined as a metal alloy in the form of a very thin "band," "string," or "band" in a crystalline or amorphous state. In addition, ‘ribbon’ may be a metal alloy, but a separate term “Ribbon” is used due to its external appearance. Fe-Si-B is used as the main material for the ribbon, and at least one of Nb, Cu or Ni is used. It can be manufactured into various compositions by adding one additive.

In addition, the ribbon as the material of the magnetic sheet portions (R1, R2, R3) is an example, and according to another embodiment, the magnetic sheet portions (R1, R2, R3) are Fe, Ni, Co, Mo, Si, Al. and B. It may be composed of a ribbon made of a metallic magnetic powder made of one or a combination of two or more elements selected from among the elements selected from B, or a composite material of the ribbon and a polymer.

The thicknesses T11, T12, and T13 of the first to third magnetic sheet portions R1, R2, and R3 in the vertical direction may be the same or different from each other.

Additionally, the thicknesses T11, T12, and T13 of the first to third magnetic sheet portions R1, R2, and R3 in the vertical direction may be uniform or non-uniform along the horizontal direction. Here, the horizontal direction is a direction perpendicular to the thickness direction of the magnetic sheet 210, and may mean, for example, at least one of the y-axis direction or the z-axis direction.

For example, the vertical thicknesses (T11, T12, T13) of the first to third magnetic sheet portions (R1, R2, R3) may be 0.1 ㎛ to 200 ㎛, for example, 0.8 ㎛, The embodiment is not limited to this.

Meanwhile, the adhesive part may be disposed between two surfaces of adjacent magnetic sheet parts (hereinafter referred to as 'first surface' and 'second surface') facing each other among the stacked magnetic sheet parts. For example, referring to FIG. 4 , the first adhesive portion A1 may be disposed between the first magnetic sheet portion R1 and the second magnetic sheet portion R2 that are adjacent to each other. Likewise, the second adhesive portion A2 may be disposed between the second magnetic sheet portion R2 and the third magnetic sheet portion R3 that are adjacent to each other.

For example, the first adhesive portion A1 may be disposed between the bottom surface RL1 of the first magnetic sheet portion R1 and the upper surface RU2 of the second magnetic sheet portion R2, and the second adhesive portion A2 ) may be disposed between the bottom surface (RL2) of the second magnetic sheet portion (R2) and the top surface (RU3) of the third magnetic sheet portion (R3). Here, the bottom surfaces (RL1) and top surfaces (RU2) facing each other correspond to the first and second surfaces, respectively, and the bottom surfaces (RL2) and top surfaces (RU3) facing each other correspond to the first and second surfaces, respectively. do.

The thickness T21 of the first adhesive portion A1 in the vertical direction from the bottom surface RL1 of the first magnetic sheet portion R1 to the upper surface RU2 of the second magnetic sheet portion R2 facing thereto is 0.1 μm. to 10 ㎛, for example, may be 1.4 ㎛, but the embodiment is not limited thereto. In addition, the thickness T22 of the second adhesive portion A2 is also measured in the vertical direction from the bottom surface RL2 of the second magnetic sheet portion R2 to the upper surface RU3 of the third magnetic sheet portion R3 facing thereto. It may be 0.1 ㎛ to 10 ㎛, for example, 1.4 ㎛, but the embodiment is not limited thereto. For example, the minimum structural unit that implements the magnetic sheet 210 may have a thickness of 3 ㎛, but the embodiment is not limited thereto.

Additionally, the thicknesses T21 and T22 of each of the first and second adhesive portions A1 and A2 may be uniform or non-uniform along the horizontal direction (eg, y-axis and z-axis directions).

Hereinafter, embodiments of each of the first and second adhesive portions A1 and A2 shown in FIG. 4 will be described with reference to the accompanying drawings.

FIG. 5A shows a plan view of an embodiment 300A of the adhesive part included in the magnetic sheet 210, and FIG. 5B shows a cross-sectional view taken along line II' shown in FIG. 5A.

The adhesive portion 300A shown in FIGS. 5A and 5B corresponds to an example of each of the first and second adhesive portions A1 and A2 shown in FIG. 4 .

According to one embodiment, the adhesive portion 300A may include a plate 310A and an adhesive 320A.

Plate 310A may have a net planar shape as illustrated in FIG. 5A. In the net planar shape shown in FIG. 5A, the planar shape of the NK (Net Knot) is illustrated as being square, but the embodiment is not limited to this. According to another embodiment, the planar shape of the mesh NK may include at least one of a polygon, circle, or oval other than a square.

Additionally, the plate 310A may be made of a material having at least one of softness and magnetic properties. For example, the plate 310A may be made of magnetic stainless steel (Fe-Cr-Al-Si), sandust (Fe-Si-Al), permalloy (Fe-Ni), Fe-Si alloy silicon copper (Fe-Cu- It may contain at least one of Si), Fe-S-B(-Cu-Nb) alloy, Fe-Si-Cr-Ni alloy, Fe-Si-Cr alloy, Fe-Si-Al-Ni-Cr alloy, or ferrite. , the embodiment is not limited to this.

Additionally, the adhesive 320A is disposed to surround the plate 310A. Because of this, the magnetic sheet portion and the plate 310A, which are adjacent to each other, may be spaced apart from each other by the adhesive 320A. That is, when the adhesive portion 300A corresponds to the embodiment of the first adhesive portion A1, the plate 310A may be spaced apart from each of the first and second magnetic sheet portions R1 and R2 by the adhesive 320A. there is. In addition, when the adhesive portion 300A corresponds to the embodiment of the second adhesive portion A2, the plate 310A may be separated from each of the second and third magnetic sheet portions R2 and R3 by the adhesive 320A. there is. Additionally, the adhesive 320A may be connected through the mesh NK of the plate 310A.

The adhesive 320A may include a first adhesive layer 320A-1, a second adhesive layer 320A-2, and a third adhesive layer 320A-3.

The first adhesive layer 320A-1 may be disposed between the plate 310A and a first surface, which is one of two surfaces of adjacent magnetic sheet portions, facing each other. The second adhesive layer 320A-2 may be disposed between the plate 310A and the second surface, which is the other of the two surfaces of adjacent magnetic sheet parts facing each other.

For example, when the adhesive portion 300A shown in FIGS. 5A and 5B corresponds to the embodiment of the first adhesive portion A1 shown in FIG. 4, the first adhesive layer 320A-1 is adjacent to each other. It may be disposed between the plate 310A and the first surface RL1, which is one of the two surfaces RL1 and RU2 of the second magnetic sheet portions R1 and R2 facing each other. In addition, the second adhesive layer 320A-2 is formed on the second surface RU2, which is the other of the two surfaces RL1 and RU2 of the adjacent first and second magnetic sheet portions R1 and R2, and a plate ( 310A) can be placed between.

In addition, for example, when the adhesive portion 300A shown in FIGS. 5A and 5B corresponds to the embodiment of the second adhesive portion A2 shown in FIG. 4, the first adhesive layer 320A-1 is adjacent to each other. It may be disposed between the plate 310A and the first surface RL2, which is one of the two surfaces RL2 and RU3 of the second and third magnetic sheet parts R2 and R3 facing each other. In addition, the second adhesive layer 320A-2 is formed on the second surface RU3, which is the other of the two surfaces RL2 and RU3 of the adjacent second and third magnetic sheet parts R2 and R3, and a plate ( 310A) can be placed between.

Additionally, the third adhesive layer 320A-3 corresponds to an adhesive disposed on the mesh NK of the plate 310A. In this way, the first adhesive layer 320A-1 and the second adhesive layer 320A-2 may be connected to each other through the third adhesive layer 320A-3 disposed in the mesh NK of the plate 310A.

The adhesive 320A contains organic substances, and these adhesive ingredients include acrylic resin, urethane resin, epoxy resin, silicone resin, phenol resin, amino resin, unsaturated polyester resin, polyurethane resin, urea resin, melamine resin, and poly. There are imide resins, diallyl phthalate resins, and these modified resins, but examples are not limited thereto.

FIG. 6 shows a plan view of another embodiment 300B of an adhesive part included in the magnetic sheet 210.

The adhesive portion 300B shown in FIG. 6 corresponds to different embodiments of the first and second adhesive portions A1 and A2 shown in FIG. 4 .

According to another embodiment, the adhesive portion 300B may include a plate 310B and an adhesive 320B.

As illustrated in FIG. 5A, the meshes NK of the plate 310A may have the same size, but the embodiment is not limited thereto. That is, according to another embodiment, the mesh NK of the plate may have different sizes. For example, as illustrated in FIG. 6, the size of the mesh NK of the plate 310B in a plan view may increase from the center of the plate 310B to the edge.

As described above, except that the sizes of the plurality of meshes NK included in the plate 310B are different from each other, the adhesive portion 300B shown in FIG. 6 is the same as the adhesive portion 300A shown in FIG. 5A. Therefore, except for different parts, the description of the adhesive portion 300A shown in FIGS. 5A and 5B can be applied to the adhesive portion 300B shown in FIG. 6.

Meanwhile, the planar shapes of the plurality of meshes NK included in the plate may all be the same. For example, unlike shown in FIGS. 5A and 6 , the planar shapes of the plurality of meshes NK included in the plates 310A and 310B may all be square. However, the embodiment is not limited thereto. That is, according to another embodiment, unlike shown in FIG. 5A or 6, the planar shape of the mesh NK located in the center among the plurality of meshes NK included in the plates 310A and 310B is located at the edge. It may be different from the planar shape of the mesh (NK).

In particular, the planar shape of the plurality of meshes NK included in the plate may vary depending on the shape of the coil. In particular, as illustrated in FIG. 6, when the size NK of the mesh of the plate 310B increases from the center to the edge of the plate 310B, the planar shape of the plurality of meshes NK included in the plate By matching this coil shape, transmission efficiency can be improved.

In addition, in the case of FIGS. 5A, 5B and 6, the number of plates 310A and 310B included in the adhesive portions 300A and 300B is one, but the embodiment is not limited thereto. That is, according to another embodiment, the number of plates included in the adhesive portion 300 may be plural. That is, a plurality of plates may be stacked and arranged in a vertical direction between two surfaces of adjacent magnetic sheet parts facing each other. At this time, the plurality of stacked plates may be arranged to be spaced apart from each other at regular intervals in the vertical direction.

FIG. 7A shows a plan view of another embodiment 300C of the adhesive part included in the magnetic sheet 210, and FIG. 7B shows a cross-sectional view taken along line II-II' shown in FIG. 7A.

The adhesive portion 300C shown in FIGS. 7A and 7B corresponds to another example of the first and second adhesive portions A1 and A2 shown in FIG. 4, respectively.

According to another embodiment, the adhesive portion 300C may include a plurality of plates 310C: 310C-1, 310C-2, and 310C-3 and an adhesive 320C. 7A and 7B, the adhesive portion 300C is illustrated as including three plates 310C-1, 310C-2, and 310C-3, but the embodiment is not limited thereto. That is, according to another embodiment, the adhesive portion 300C may include two or four or more plates.

Referring to FIGS. 7A and 7B , the adhesive portion 300C may include first to third plates 310C-1, 310C-2, and 310C-3 arranged to be spaced apart from each other in the vertical direction.

The first plate 310C-1 may be disposed in the middle of the vertical positions of the adhesive portion 300C, but the embodiment is not limited to this.

The second plate 310C-2 may be disposed between the first plate 310C-1 and the first side (e.g., RL1 or RL2), and the third plate 310C-3 may be disposed between the first plate 310C-1 and the first surface (eg, RL1 or RL2). 310C-1) and the second side (eg, RU2 or RU3).

Additionally, the meshes of the plurality of plates may be arranged to alternate with each other in the vertical direction. That is, the meshes of the plurality of plates may be arranged to overlap each other at least partially in the vertical direction. For example, as illustrated in FIGS. 7A and 7B, the first to third meshes NK1, NK2, and NK3 may be arranged to alternate with each other in the vertical direction.

7A and 7B, the first plate 310C-1 has a first mesh NK1, the second plate 310C-2 has a second mesh NK2, and the third plate 310C -3) has a third mesh (NK3).

Additionally, when the adhesive portion includes a plurality of plates, the adhesive of the adhesive portion may include fourth, fifth, sixth, and seventh adhesive layers.

The fourth adhesive layer may be defined as an adhesive layer disposed between the first side, which is one of the two sides facing each other, and the uppermost plate among the plurality of plates. Referring to FIG. 7B, the fourth adhesive layer 320C-1 has a first surface (eg, RL1 or RL2), which is one of two surfaces facing each other, and a plurality of plates 310C-1, 310C-2, and 310C-. 3) It can be placed between the uppermost plates (310C-2).

The fifth adhesive layer may be defined as an adhesive layer disposed between the second side, which is the other one of the two sides facing each other, and the lowest plate among the plurality of plates. Referring to FIG. 7B, the fifth adhesive layer 320C-2 is between the second side (for example, RU2 or RU3), which is one of the two sides facing each other, and the lowest plate 310C-3 of the plurality of plates. can be placed.

The sixth adhesive layer may be defined as an adhesive layer disposed between a plurality of plates. Referring to FIG. 7B, the sixth adhesive layer 320C-3 may include 6-1 and 6-2 adhesive layers 320C-31 and 320C-32. The 6-1 adhesive layer (320C-31) may be disposed between the first plate (310C-1) and the second plate (310C-2), and the 6-2 adhesive layer (320C-32) may be disposed between the first plate (310C-1) and the second plate (310C-2). It may be placed between 310C-1) and the third plate 310C-3.

The seventh adhesive layer can be defined as an adhesive layer that connects the fourth to sixth adhesive layers through the mesh of a plurality of plates. Referring to Figure 7b, the 7th adhesive layer (320C-4) refers to the 7-1st adhesive layer (320C-41), the 7-2nd adhesive layer (320C-42), and the 7-3th adhesive layer (320C-43). You can. The 7-1 adhesive layer (320C-41) is disposed on the second mesh (NK2) of the second plate (310C-2) and connects the fourth adhesive layer (320C-1) and the 6-1 adhesive layer (320C-31). It plays a role. The 7-2 adhesive layer (320C-42) is disposed on the first mesh (NK1) of the first plate (310C-1) to form a 6-1 adhesive layer (320C-31) and a 6-2 adhesive layer (320C-32). It plays a role in connecting. The 7-3 adhesive layer (320C-43) is disposed on the third mesh (NK3) of the third plate (310C-3) and connects the 6-2 adhesive layer (320C-32) and the fifth adhesive layer (320C-2). It plays a role. In this way, the seventh adhesive layer 320C-4 disposed on the first to third meshes NK1 to NK3 of the plurality of plates 310C-1, 310C-2, and 310C-3 is connected to the fourth to sixth adhesive layers ( 320C-1, 320C-2, 320C-3) can be connected.

Additionally, at least one of the thickness of the plurality of plates, the shape of the mesh of the plurality of plates, or the size of the mesh may be the same or different from each other.

First, the thickness of the plurality of plates may be the same or different from each other. For example, referring to FIG. 7B, the thickness T31 of the first plate 310C-1, the thickness T32 of the second plate 310C-2, and the thickness T33 of the third plate 310C-3 ) may be different from each other or may be the same.

Additionally, the shapes of the meshes of the plurality of plates may be different from each other or may be the same. For example, referring to FIG. 7A, the planar shapes of the first to third meshes NK1, NK2, and NK3 of the first to third plates 310C-1, 310C-2, and 310C-3 are all square. may be identical to each other.

Additionally, the sizes of the meshes of the plurality of plates may be the same or different from each other. For example, referring to Figure 7a, the length of the first to third meshes (NK1, NK2, NK3) of the first to third plates (310C-1, 310C-2, 310C-3) in the z-axis direction (Z) are the same as each other, and are the respective lengths in the y-axis direction of the first to third meshes (NK1, NK2, NK3) of the first to third plates (310C-1, 310C-2, 310C-3) (Y1, Y2, Y3) may be the same or different from each other.

As described above, except that the number of plates is different, the adhesive portion 300C shown in FIGS. 7A and 7B is the same as the adhesive portion 300A shown in FIGS. 5A and 5B. Therefore, except for different parts, the description of the adhesive portion 300A shown in FIGS. 5A and 5B can be applied to the adhesive portion 300B shown in FIGS. 7A and 7B.

Additionally, the plurality of plates may be arranged so that the planar area where the meshes of the plurality of plates overlap in the vertical direction is minimized. That is, referring to FIGS. 7A and 7B, the first to third meshes NK1, NK2, and NK3 of the first to third plates 310C-1, 310C-2, and 310C-3 have a planar area in the vertical direction ( OA) can overlap. To minimize this planar area (OA), the first to third plates 310C-1, 310C-2, and 310C-3 may overlap in the vertical direction.

FIG. 8 shows a plan view of another example 300C of an adhesive part included in the magnetic sheet 210.

The adhesive portion 300D shown in FIG. 8 corresponds to another example of each of the first and second adhesive portions A1 and A2 shown in FIG. 4 .

According to another embodiment, the adhesive portion 300D may include a plurality of plates 310D and an adhesive 320D.

As an example of minimizing the plan area (OA) where a plurality of meshes overlap in the vertical direction, as shown in FIG. 8, the meshes of the plurality of plates 310D may have a honeycomb planar shape, that is, a hexagonal planar shape. .

According to another embodiment, unlike shown in FIGS. 7A and 7B, the plurality of plates may overlap in the vertical direction so that the meshes of the plurality of plates do not overlap in the vertical direction. As such, the planar area OA where the first to third meshes NK1, NK2, and NK3 shown in FIGS. 7A and 7B overlap in the vertical direction may be '0'.

Additionally, the adhesive portion 300C shown in FIGS. 7A and 7B includes three plates 310C-1, 310C-2, and 310C-3, while the adhesive portion 300D shown in FIG. 8 includes two plates ( 310D). As described above, except that the planar shapes of the meshes of the plurality of plates are different and the number of the plurality of plates is different, the adhesive portion 300D shown in FIG. 8 is the same as the adhesive portion 300C shown in FIG. 7A. . Therefore, except for different parts, the description of the adhesive portion 300C shown in FIGS. 7A and 7B can be applied to the adhesive portion 300D shown in FIG. 8.

Referring again to FIG. 4, the magnetic sheet 210 according to the embodiment may further include a base adhesive portion (A0). If the third magnetic sheet portion R3 is disposed at the bottom of the magnetic sheet portions included in the magnetic sheet 210, the base adhesive portion A0 may be disposed below the third magnetic sheet portion R3. .

The base adhesive portion A0 may have a greater thickness in the x-axis direction than the first and second adhesive portions A1 and A2. Additionally, the base adhesive portion A0 may or may not have magnetism. A substrate (not shown) of a wireless power receiving device may be placed under the base adhesive portion A0.

Hereinafter, the magnetic properties of magnetic sheets according to examples and comparative examples will be compared and examined as follows with reference to FIGS. 9A and 9B.

FIG. 9A is a cross-sectional view for explaining the magnetic properties of the magnetic sheet 210 according to an embodiment, and FIG. 9B is a cross-sectional view for explaining the magnetic properties of the magnetic sheet according to a comparative example.

Referring to FIG. 9A, the magnetic sheet 210 according to the embodiment applies magnetism to each of the first and second adhesive portions A1 and A2 disposed between the first to third magnetic sheet portions R1, R2, and R3. Since a possible plate is included, the effective permeability increases and the loss of magnetic flux can be reduced.

On the other hand, as shown in FIG. 9b, adhesive films (AF1 to AF4) that do not include a plate that can have magnetism are disposed between each magnetic sheet portion (R1, R2, R3, and R4). In this case, the magnetic flux loss due to the adhesive film, which is an insulator, is large, so more magnetic sheet units must be stacked to obtain the same effective permeability as in the case of FIG. 9A.

In general, if a magnetic material is contained in the adhesive portion, the adhesive strength of the adhesive portion may decrease, and if the thickness of the adhesive portion is thin, the decrease in adhesive strength may become more serious. However, in the case of the magnetic sheet 210 according to the embodiment, plates (310A, 310B, 310C, 310D) having a magnetic net planar shape are arranged and the mesh (NK:NK1) of the plates (310A, 310B, 310C, 310D) Since the adhesives (320A, 320B, 320C, 320D) are connected through , NK2, NK3), the reduction in effective permeability can be minimized and transmission efficiency can be improved. In particular, according to the embodiment, since the plates (310A, 310B, 310C, 310D) are surrounded by adhesives (320A, 320B, 320C, 320D), the reduction in effective permeability is minimized while the adhesive portions (320A, 320B, 320C, 320D) Reliability can be improved by maintaining the adhesive strength without deterioration. In addition, while it is generally difficult to control the uniformity of the thickness of the adhesive portion when magnetic materials are contained in the adhesive portion, as in the embodiment, the plates 310A, 310B, 310C, and 310D are formed by the adhesives 320A, 320B, 320C, and 320C. ), the thickness of the adhesive portions 300A, 300B, 300C, and 300D can be uniformly controlled.

Moreover, the adhesive film has a structure in which an adhesive is disposed above and below a substrate (i.e., polymer film). Considering this, as the number of stacked magnetic sheet parts increases, the number of adhesive films disposed between the magnetic sheet parts also increases. This increases the thickness of the magnetic sheet according to the comparative example shown in Figure 9b, leading to the problem of difficulty in thinning it. there is.

Meanwhile, according to one embodiment, a metal ribbon is used as the magnetic sheet portion (for example, R1, R2, and R3) constituting the magnetic sheet 210, but eddy current loss can also be reduced by forming cracks in the metal ribbon. .

Figure 10 is a graph comparing the real permeability by frequency before and after forming a crack in the metal ribbon. Here, the difference between the permeability and permeability loss may mean the actual permeability.

Referring to FIG. 10, it can be seen that in the frequency range where wireless charging is used, for example, about 150 kHz band, the real permeability after forming a crack in the metal ribbon is significantly larger than the real permeability before forming the crack.

When a metal ribbon is used as the magnetic sheet portion of the magnetic sheet 210, eddy current loss can be reduced and transmission efficiency can be improved by forming cracks in the metal ribbon.

Preferably, when a uniform pattern of cracks is formed in the metal ribbon, the transmission efficiency of the magnetic sheet 210 is improved and more uniform performance can be obtained.

11 to 13 show top views of magnetic sheet portions (eg, R1, R2, and R3) according to embodiments.

11 to 13, the magnetic sheet portion (e.g., R1, R2, R3) constituting the magnetic sheet 210 includes three or more lines 720 radiating from a predetermined point 710. A pattern 700 may be formed. Here, the pattern may be formed as a crack. At this time, a plurality of patterns 700 may be repeatedly formed on the magnetic sheet portion, and one pattern 700 may be arranged to be surrounded by a plurality of patterns, for example, 3 to 8 patterns 700. there is.

In this way, when a repetitive pattern is formed in the magnetic sheet portion (eg, R1, R2, and R3) of the magnetic sheet 210, eddy current loss can be reduced and uniform and predictable transmission efficiency can be obtained.

At this time, the average diameter of each pattern 700 may be 50 ㎛ to 600 ㎛. If the diameter of the pattern 700 is less than 50 μm, excessive metal particles may be generated on the surface of the metal ribbon when cracks are formed. If there are metal particles on the surface of the magnetic sheet 210, there is a risk of circuit short circuit because the metal particles may penetrate into the circuit. On the other hand, when the diameter of the pattern 700 exceeds 600 ㎛, the distance between the patterns 700 is large, so the effect of crack formation, that is, the effect of increasing the real permeability, may be reduced.

14 to 15 show top views of magnetic sheet portions (eg, R1, R2, and R3) according to another embodiment.

14 to 15, the magnetic sheet portion (e.g., R1, R2, R3) of the magnetic sheet 210 includes three or more lines 720 radiating from a predetermined point 710 and a border surrounding them. A pattern 700 including 730 is formed. Here, the pattern may be formed as a crack. Here, the edge 730 may not be a completely cut crack, but may mean that some cracks are connected and some are broken. At this time, a plurality of patterns 700 may be repeatedly formed on the magnetic sheet portion (e.g., R1, R2, and R3), and one pattern 700 may be formed of a plurality of patterns, for example, 3 to 8 patterns. It may be arranged to be surrounded by the pattern 700.

In this way, when a repetitive pattern is formed in the magnetic sheet portion (eg, R1, R2, and R3), eddy current loss can be reduced and uniform and predictable transmission efficiency can be obtained.

At this time, the average diameter of each pattern 700 may be 50 ㎛ to 600 ㎛, and since the characteristics depending on the range are similar to those described above, overlapping description will be omitted.

When the pattern 700 includes an edge 730, the effect of crack formation is further increased, and the boundary between the patterns 700 is clearly distinguished so that the repetitive pattern pattern becomes clear, so the uniformity of quality can be further increased.

Additionally, the pattern 700 may include six or more lines 720 radiating from a predetermined point 710 and a border 730 surrounding them. When six or more lines 720 radiating within the edge 730 are formed, the effect of crack formation can be maximized.

Figure 16 shows a top view of a magnetic sheet portion (eg, R1, R2, and R3) according to another embodiment.

Referring to FIG. 16, the magnetic sheet portion (e.g., R1, R2, R3) of the magnetic sheet 210 includes three or more lines 720 radiating from a predetermined point 710 and two or more lines surrounding them. A pattern 700 including an edge 730 is formed. Here, the pattern may be formed as a crack. At this time, a plurality of patterns 700 may be repeatedly formed on the magnetic sheet portion (e.g., R1, R2, and R3), and one pattern 700 may be formed of a plurality of patterns, for example, 3 to 8 patterns. It may be arranged to be surrounded by the pattern 700.

Meanwhile, in the case of the cracking process, it may include a process of implementing surface patterning by applying pressure to the magnetic sheet portion itself (e.g., R1, R2, R3) or breaking the internal structure by applying a certain crushing force to the surface itself. there is. Through this, by including a fractured structure on the surface or inside, the permeability can be reduced and the transmission efficiency can be further increased. For example, in order to form cracks in a uniform pattern on a metal ribbon, pressure can be applied using a roller made of urethane material that protrudes in a pattern shape. Rollers made of urethane can form crack patterns more uniformly than rollers made of metal, and can minimize the phenomenon of metal particles remaining on the surface of the metal ribbon. At this time, the pressurizing process may be performed for 10 minutes or less under conditions of 25°C to 200°C and 10 to 3000 Pa.

In this way, magnetic permeability and saturation magnetic can increase and reduce eddy current loss. Additionally, by forming cracks in a uniform pattern on the metal ribbon, transmission efficiency can be increased and uniform and predictable performance can be obtained. Of course, depending on the embodiment, a metal ribbon with randomly shaped cracks formed in the magnetic sheet portion (eg, R1, R2, and R3) may be used.

Meanwhile, according to the embodiment, in the magnetic sheet 210 having a stacked structure of a plurality of magnetic sheet parts (eg, R1, R2, R3), some magnetic sheet parts (eg, R1, R2, R3) The structure that does not undergo a cracking or breaking process (hereinafter referred to as “Non-Cracking”) is used to form some of the remaining magnetic sheet parts (e.g., R1, R2, R3). can be made to have a fractured structure.

For example, each or both surfaces of the uppermost magnetic sheet portion (e.g., R1) or the lowermost magnetic sheet portion (e.g., R3) may have a structure that does not undergo a process such as a cracking or breaking process ( The magnetic sheet portion (hereinafter referred to as “Non-Cracking”) may be arranged.

The stacked structure of the outermost magnetic sheet portions (e.g., R1, R3) having such a non-fractured structure causes salt water to infiltrate in a later process due to the fractured structure of the remaining magnetic sheet portions (e.g., R2). It is possible to solve the problem of the shattered structure being exposed to the external surface of the magnetic sheet 210 and damaging the protective film, etc. in a later linking process.

In particular, in the case of the magnetic sheet portion (e.g., R1, R2, R3) having a fractured structure according to the embodiment, the magnetic sheet portion has a relatively low magnetic permeability and internal porosity compared to the magnetic sheet portion having a non-fractured structure. The magnetic sheet portion with a fractured structure exhibits relatively higher characteristics compared to the magnetic sheet portion with a non-fractured structure.

Although the above description focuses on the examples, this is only an example and does not limit the present invention, and those skilled in the art will be able to You will see that various variations and applications are possible. For example, each component specifically shown in the examples can be modified and implemented. And these variations and differences in application should be construed as being included in the scope of the present invention as defined in the appended claims.

200: wireless power receiving device 210: magnetic sheet
220: Receiving coil 300A, 300B, 300C, 300D: Adhesive part
310A, 310B, 310C, 310D: Plate 320A, 320B, 320C, 320D: Adhesive
1000: Transmitting unit 2000: Receiving unit
2100: Receiving side coil part 2200: Receiving side matching part
2300: AC/DC converter on the receiving side 2400: DC/DC converter on the receiving side
2500: Load unit 2600: Receiving side communication and control unit

Claims (10)

at least two stacked magnetic sheet portions; and
An adhesive portion disposed between two surfaces of first and second magnetic sheet portions adjacent to each other among the stacked magnetic sheet portions,
The adhesive part
A plate having a mesh planar shape and including a mesh; and
Comprising an adhesive disposed surrounding the plate to space the plate from the first and second magnetic sheet portions,
The plate is
A magnetic sheet comprising a plurality of plates stacked in a vertical direction between the first surface of the first magnetic sheet part and the second surface of the second magnetic sheet part. The method of claim 1, wherein the adhesive
a first adhesive layer disposed between the first surface, which is one of the two surfaces facing each other, and the plate;
a second adhesive layer disposed between the second surface, which is the other one of the two facing surfaces, and the plate; and
A magnetic sheet including a third adhesive layer connecting the first adhesive layer and the second adhesive layer through the mesh. delete The magnetic sheet of claim 1, wherein at least some of the meshes of the plurality of plates do not overlap in the vertical direction. The magnetic sheet of claim 1, wherein the meshes of the plurality of plates are arranged to overlap each other at least partially in the vertical direction. The magnetic sheet of claim 1, wherein at least one of thickness, mesh shape, or mesh size of each of the plurality of plates is the same. The magnetic sheet of claim 1, wherein the planar shape of the mesh includes at least one of a circular shape, an oval shape, and a polygonal shape. The magnetic sheet of claim 1, wherein the at least one plate has at least one property of ductility or magnetism. The method of claim 8, wherein the at least one plate is made of magnetic stainless steel (Fe-Cr-Al-Si), sandust (Fe-Si-Al), permalloy (Fe-Ni), Fe-Si alloy silicon copper (Fe -Cu-Si), Fe-S-B(-Cu-Nb) alloy, Fe-Si-Cr-Ni alloy, Fe-Si-Cr alloy, Fe-Si-Al-Ni-Cr alloy, or ferrite. magnetic sheet. In a wireless power receiving device that receives power transmitted from a wireless power transmitting device,
Board;
A magnetic sheet disposed on the substrate; and
It is disposed on the magnetic sheet and includes a coil that receives electromagnetic energy radiated from the wireless power transmission device,
The magnetic sheet is
at least two stacked magnetic sheet portions; and
An adhesive portion disposed between two surfaces of first and second magnetic sheet portions adjacent to each other among the stacked magnetic sheet portions,
The adhesive part
A plate having a mesh planar shape and including a mesh; and
Comprising an adhesive that surrounds the plate and separates the plate from the first and second magnetic sheet portions,
The plate is
A wireless power receiving device comprising a plurality of plates stacked in a vertical direction between the first surface of the first magnetic sheet part and the second surface of the second magnetic sheet part.

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