KR102406262B1 - Shielding unit for wireless charging - Google Patents

Abstract

A shielding unit for wireless charging is provided. The shielding unit for wireless charging according to an exemplary embodiment of the present invention is disposed on one surface of the antenna unit, and includes a magnetic field shielding sheet; and a metal thin film to perform a heat dissipation function for dissipating heat to the outside together with a protective function to protect the magnetic field shielding sheet, and the magnetic field opposite to one side of the magnetic field shielding sheet on which the antenna unit is disposed a metal protective film disposed on the exposed surface of the shielding sheet and directly attached to the exposed surface of the magnetic shielding sheet through an adhesive layer having thermal conductivity; and at least one slit formed in an area corresponding to the wireless charging antenna disposed on one side of the magnetic field shielding sheet, and formed through the metal protective film to increase the resistance of the metal protective film to suppress the generation of eddy currents. Including, wherein the slit is formed to have a predetermined length in a direction perpendicular to the longitudinal direction of the pattern constituting the wireless charging antenna, or a predetermined length in a direction perpendicular to the tangent of the pattern constituting the wireless charging antenna. The metal protective film is provided to have a thickness of 1/9 to 1/3 with respect to the thickness of the magnetic field shielding sheet.

Description

Shielding unit for wireless charging

The present invention relates to a shielding unit for wireless charging.

Recently, various functions such as radio frequency identification (RFID), near field communication (NFC), wireless charging (WPT), and interactive pen tablet are being added to portable terminals including mobile phones and tablet PCs.

NFC is a non-contact short-distance wireless communication module that uses a 13.56 MHz frequency band as one of RFID, an electronic tag, and refers to a technology that transmits data between terminals at a short distance of 10 cm. NFC is a file transfer method, as well as mobile payment, and is widely used in supermarkets and general stores to transmit product information or travel information for visitors, traffic, and access control locks.

In addition, the 'Android Beam' provided in smartphones recently announced by Google is a short-distance communication (NFC)-based short-distance information transmission and reception function. It provides a function to forward to another phone.

On the other hand, the portable terminal is equipped with a wireless charging function for wirelessly charging a built-in battery. Such wireless charging includes a wireless power receiving module built into the portable terminal and a wireless power transmission for supplying power to the wireless power receiving module. made by modules.

At this time, the wireless power transmission module and the wireless power reception module shield an antenna unit for transmitting or receiving a wireless signal and a magnetic field generated from the antenna unit to prevent external leakage and include a shielding sheet for focusing in a required direction. be prepared

A magnetic member is usually used as the shielding sheet, and a fluororesin-based protective film such as PET is attached to the magnetic member to prevent the shielding sheet from being exposed to the outside.

However, the conventional protective film as described above does not smoothly perform a function as a protective film, such as being torn or easily scratched by an external impact because the strength of the material itself is weak.

On the other hand, recently, electronic devices, such as mobile phones, are becoming lighter, thinner, smaller and smaller, and accordingly, parts built into the electronic devices must also be made lighter, thinner and smaller. In the case of a wireless power receiving module embedded in a mobile phone, the overall thickness is about 0.3T, and it will become even thinner in the future.

In order to satisfy the characteristics required in the very thin thickness as described above, research and development are being conducted from various angles. As a part of that, the function of supporting the functions of adjacent parts by cooperating with other adjacent parts through multifunctionalization of each part constituting the wireless power receiving module, that is, by changing the material or shape of the part that had only one unique function. There is a need for a method that can improve characteristics while maintaining the same thickness as existing products or having a thinner thickness by adding

KR 10-2014-0147518 A

The present invention has been devised in view of the above points, and by replacing the protective film attached to the exposed surface of the shielding sheet with a metal material to increase the rigidity of the material itself, it is prevented from being easily damaged by an external impact, thereby protecting it from the external environment. An object of the present invention is to provide a shielding unit for wireless charging that can increase the protection function of the device.

In addition, the present invention replaces the protective film attached to one side of the shielding sheet with a metal thin film having thermal conductivity to add a heat dissipation function in addition to the protection function, thereby helping to improve the heat dissipation efficiency of the wireless power transmission/reception module. There is another purpose to providing units.

In order to solve the above problems, the present invention is disposed on one surface of an antenna unit, comprising: a magnetic field shielding sheet; and a metal thin film to perform a heat dissipation function for dissipating heat to the outside together with a protective function to protect the magnetic field shielding sheet, and the magnetic field opposite to one side of the magnetic field shielding sheet on which the antenna unit is disposed a metal protective film disposed on the exposed surface of the shielding sheet and directly attached to the exposed surface of the magnetic shielding sheet through an adhesive layer having thermal conductivity; and at least one slit formed in an area corresponding to the wireless charging antenna disposed on one side of the magnetic field shielding sheet, and formed through the metal protective film to increase the resistance of the metal protective film to suppress the generation of eddy currents. Including, wherein the slit is formed to have a predetermined length in a direction perpendicular to the longitudinal direction of the pattern constituting the wireless charging antenna, or a predetermined length in a direction perpendicular to the tangent of the pattern constituting the wireless charging antenna. It is formed to have a, and the metal protective film provides a shielding unit for wireless charging provided to have a thickness of 1/9 to 1/3 with respect to the thickness of the magnetic field shielding sheet.

As an embodiment of the present invention, the metal protective film may be made of a metal thin film having a thermal conductivity of 200 W/m·K or more, and more specifically, it may be made of an aluminum foil or a copper foil.

In this case, the metal protective film may be directly attached to one surface of the magnetic field shielding sheet through an adhesive layer having thermal conductivity.

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In addition, the metal protective film may include a base layer made of a metal material, and a coating layer that is radiation-coated on at least one surface of the base layer. In this case, the coating layer may include at least one selected from among ceramics and metal oxides.

In addition, the magnetic field shielding sheet may include any one of a ribbon sheet, a polymer sheet, and a ferrite sheet of an amorphous alloy or nano-grain alloy. In this case, the ferrite may be any one of Mn-Zn ferrite or Ni-Zn ferrite.

In addition, the magnetic field shielding sheet may be configured by stacking a plurality of ribbon sheets of amorphous alloy or ribbon sheets of nano-crystalline alloy.

In addition, the magnetic field shielding sheet may be formed separately into a plurality of micro-pieces, the plurality of micro-pieces may be entirely insulated or partially insulated between neighboring micro-pieces, and the plurality of micro-pieces are 1㎛ ~ It may have a size of 3 mm.

In addition, the plurality of fine pieces may be formed in an irregular shape.

In addition, the magnetic field shielding sheet may be composed of a first sheet and a second sheet having different characteristics in a predetermined frequency band.

According to the present invention, the protective film attached to one surface of the magnetic shielding sheet is replaced with a metal material to increase the rigidity of the material itself, thereby preventing it from being easily damaged by an external impact, thereby enhancing the protective function of the shielding sheet.

In addition, the present invention replaces the protective film attached to one side of the magnetic field shielding sheet with a metal protective film made of a metal material having thermal conductivity to add a heat dissipation function to the protection function, thereby satisfying the heat dissipation performance required by the wireless charging method. Thinning can be realized by reducing the thickness.

In addition, the present invention applies a slit-like structure for suppressing eddy current loss to the metal protective film and also applies a coating layer for improving emissivity, thereby improving heat dissipation efficiency and wireless charging efficiency.

1 is a perspective view showing a shielding unit for wireless charging according to an embodiment of the present invention;
Figure 2 is a cross-sectional view of Figure 1;
3A and 3B are schematic views showing the arrangement relationship between the slit and the wireless charging antenna when the slit is formed in the metal protective film applied to the shielding unit for wireless charging according to an embodiment of the present invention, FIG. 3A is a wireless A case in which the charging antenna is provided in a rectangular shape, Figure 3b is a view showing a case in which the wireless charging antenna is provided in a circular shape;
4A to 4D are views showing various shapes of slits formed in a metal protective film applied to a shielding unit for wireless charging according to an embodiment of the present invention;
5 is a metal protection film applied to a shielding unit for wireless charging according to an embodiment of the present invention, and is a view showing a case in which a coating layer is formed on at least one surface of the metal protection film;
6 is a view showing a shielding sheet applied to a shielding unit for wireless charging according to an embodiment of the present invention, a view showing a laminated form of a ribbon sheet of an amorphous alloy or nano-crystalline alloy;
7a to 7c are when the shielding sheet applied to the shielding unit for wireless charging according to an embodiment of the present invention is composed of a first sheet and a second sheet having different characteristics, the first sheet and the second sheet As a view showing the arrangement relationship, Fig. 7a is a case in which the first sheet is laminated on one surface of the second sheet, and Fig. 7b is a case in which the first sheet having the same thickness as the second sheet is accommodated in the second sheet, , Figure 7c is a view showing a case in which the first sheet having a thinner thickness than the second sheet is accommodated inside the second sheet,
8 is a view schematically showing a wireless power charging module to which a shielding unit for wireless charging according to an embodiment of the present invention is applied, and;
9 is a cross-sectional view of FIG. 8 .

Hereinafter, with reference to the accompanying drawings, embodiments of the present invention will be described in detail so that those of ordinary skill in the art can easily carry out the present invention. The present invention may be embodied in many different forms and is not limited to the embodiments described herein. In order to clearly explain the present invention in the drawings, parts irrelevant to the description are omitted, and the same reference numerals are added to the same or similar elements throughout the specification.

The shielding unit 100 according to an embodiment of the present invention includes a magnetic field shielding sheet 110 and a metal protective film 120 as shown in FIGS. 1 and 2 .

The magnetic field shielding sheet 110 shields the magnetic field generated when the antenna unit 10 transmits or receives a radio signal in a predetermined frequency band, thereby increasing the collection speed of the magnetic field, thereby operating in a predetermined frequency band. is to increase

Here, the antenna unit 10 includes at least one antenna for transmitting or receiving a radio signal in a predetermined frequency band, and may be composed of a plurality of antennas 12, 13, and 14 performing different roles. .

As an example, the plurality of antennas (12, 13, 14) may include any one or more of the wireless charging antenna 12, the MST antenna 13 and the NFC antenna 14 operating in different frequency bands. (see FIGS. 3A, 3B and 7). In addition, the plurality of antennas 12, 13, and 14 may be composed of a circular, oval or rectangular flat coil wound in a clockwise or counterclockwise direction, and made of a synthetic resin such as polyimide (PI) or PET. A conductor such as copper foil may be patterned in a loop shape on at least one surface of the circuit board 11 or may be formed in a loop shape metal pattern using conductive ink.

The magnetic field shielding sheet 110 is made of a material having a magnetic field to shield the magnetic field generated by the antenna unit (10).

For example, the magnetic field shielding sheet 110 may be a ribbon sheet, a ferrite sheet, or a polymer sheet of an amorphous alloy or nano-crystalline alloy.

In this case, the ferrite sheet may be a sintered ferrite sheet, and Ni-Zn ferrite or Mn-Zn ferrite may be used. In addition, as the amorphous alloy or nano-crystalline alloy, a Fe-based or Co-based magnetic alloy may be used.

In addition, as shown in Figure 6, the magnetic shielding sheet 110' reveals that the ribbon sheets 111a, 111b, 111c of a plurality of amorphous alloys or nano-crystalline alloys may be configured in a stacked form.

In addition, the magnetic field shielding sheet 110 may be formed to be separated into a plurality of fine pieces to suppress the generation of eddy currents by increasing the resistance, and the plurality of fine pieces may be entirely insulated or partially insulated between neighboring fine pieces. It can be provided as much as possible.

In this case, the plurality of fine pieces may be provided in a size of 1 μm to 3 mm, and each piece may be made irregularly and randomly.

And when the magnetic field shielding sheet 110 is formed by stacking a plurality of sheets separated into fine pieces, an adhesive layer made of a non-conductive material is disposed between each sheet so that it can permeate between a pair of sheets stacked on each other By doing so, the adhesive layer may serve to insulate a plurality of fine pieces constituting each sheet. Here, the adhesive layer may be provided as an adhesive or may be provided in a form in which an adhesive is applied to one or both sides of a film-type substrate.

The metal protection film 120 is attached to the magnetic field shielding sheet 110 via an adhesive layer 130 on one surface of the magnetic field shielding sheet 110 , preferably based on the magnetic field shielding sheet 110 . It is disposed on the opposite surface of the antenna unit 10 , in other words, on the exposed surface of the magnetic field shielding sheet 110 exposed to the outside.

At this time, the metal protective film 120 performs a function as an auxiliary heat dissipation sheet for emitting heat generated from a heat source to the outside together with a protective function for protecting the magnetic field shielding sheet 110 .

To this end, the metal protective film 120 is made of a metal material having thermal conductivity and radiates heat transferred from the heat source to the outside, so that heat is radiated through the metal protective film 120 without using a separate heat dissipation member such as graphite. this will be done

At this time, the metal protective film 120 may be provided to have a thin thickness so as not to increase the overall thickness of the shielding unit 100 , and may be provided to have a relatively thin thickness compared to the magnetic field shielding sheet 110 . . Preferably, the metal protective film 120 may be provided to have a thickness of 1/9 to 1/3 with respect to the thickness of the magnetic field shielding sheet 110 .

That is, the metal protective film 120 is provided to have approximately the same thickness as a conventional protective film attached to at least one surface of the magnetic shielding sheet 110 in order to protect the magnetic field shielding sheet 110 , so that the magnetic shielding sheet ( By being attached to one side of the 110), it is possible to replace the conventional protective film used to simply protect the magnetic field shielding sheet 110.

Accordingly, the metal protective film 120 serves to protect the magnetic field shielding sheet 110 and to radiate heat to the outside, unlike the conventional protective film that simply protects the magnetic field shielding sheet 110 from the external environment. The heat dissipation function for

Here, the metal material constituting the metal protection film 120 may be in the form of copper, aluminum, or a combination thereof having excellent thermal conductivity, and may be in the form of an alloy including at least one of copper or aluminum, and the metal protection The film 120 may be provided to have a thickness of 1/9 to 1/3 with respect to the thickness of the magnetic field shielding sheet 110 .

For example, the metal protective film 120 may be made of a metal thin film having a thermal conductivity of 200 W/m·K or more, and may be provided in the form of an aluminum foil or copper foil, and the metal thin film is the magnetic field shielding sheet 110 of the It may be provided to have a thickness of 1/9 to 1/3 with respect to the thickness.

This is because the metal protective film 120 made of a metal material is provided to have the same thickness or less than that of the conventional protective film to replace the conventional protective film, thereby dissipating heat in the protective function without increasing the overall thickness of the shielding unit. In order to be able to add functions.

Accordingly, in the shielding unit 100 for wireless charging according to the present invention, the metal protective film 120 is made of a metal material having a thin thickness and is attached to one surface of the magnetic shielding sheet 110 according to the conventional method that performed only a protective function. A heat dissipation function may be added to the protection function while having the same thickness or less than that of the protection film.

Due to this, it is possible to simultaneously perform a protective function and a heat dissipation function through the metal protective film 120 without increasing the overall thickness of the shielding unit 100 for wireless charging, so the shielding unit for wireless charging according to the present invention ( 100), it is possible to simultaneously perform the shielding function of shielding the magnetic field and the heat dissipation function for heat dissipation.

In addition, since the metal protective film 120 is made of a metal material, the rigidity of the material itself is increased, and thus, the rigidity is greatly increased compared to a conventional protective film made of a material such as PET. Accordingly, the magnetic field shielding sheet 110 is stably protected from external shocks through a metal material with high rigidity of the material itself, unlike the conventional protective film, which is easily torn or damaged by external shocks, thereby shielding the magnetic field. By preventing deformation due to cracks and cracks of the sheet 110, it is possible to minimize the characteristic change.

As an example, when the shielding unit 100 for wireless charging according to the present invention is applied to the wireless charging module 1 including the antenna unit 10 and the shielding unit 100 as shown in FIGS. 8 and 9 . , in particular, when applied to a wireless power receiving module with severe restrictions on the overall thickness, there is no need to use a separate heat dissipation member for dissipating the heat generated by the antenna unit 10 to the outside, so the overall thickness of the wireless power receiving module can be further reduced.

At this time, for the purpose of simply protecting the magnetic field shielding sheet 110 on the other surface of the magnetic field shielding sheet 110 to which the metal protective film 120 is not attached, polyethylene terephthalate (PET), polypropylene (PP), polytere A protective film 140 made of a fluororesin-based film including at least one selected from phthalate (PTFE) may be additionally provided.

In this case, when the antenna unit 10 is attached to one surface of the shielding unit 100 for wireless charging according to the present invention, the protective film 140 is removed without the need to use a separate adhesive means, and the protective film 140 and This is to enable the antenna unit 10 to be attached to one surface of the magnetic shielding sheet 110 through the adhesive layer 130 disposed between the magnetic field shielding sheets 110 .

Meanwhile, the adhesive layer 134 may be provided to have thermal conductivity, thereby further enhancing the heat dissipation effect. Such an adhesive layer 134 may be provided with an adhesive containing a thermally conductive component, or may have a plate-shaped substrate and an adhesive containing a thermally conductive component applied to at least one surface of the substrate.

For example, the adhesive may include a heat-curing or photo-curing type adhesive component or a pressure-sensitive adhesive type adhesive component according to a selected bonding method. The adhesive component may be selected from commonly used acrylic, urethane, epoxy and silicone adhesive components, and may further include a curing agent commonly used for crosslinking the adhesive component. The curing agent is not particularly limited in the present invention as it may be selected in consideration of the specific type of the selected adhesive component and the bonding method.

In addition, for the expression of heat dissipation, the adhesive may further include a thermally conductive component, and if it has thermal conductivity, the type thereof is not limited. As a non-limiting example, the thermally conductive component may use a metal, an inorganic material, an organic material, or a mixture thereof, and specifically, aluminum (Al), nickel (Ni), copper (Cu), tin (Sn), metal powders such as zinc (Zn), tungsten (W), iron (Fe), silver (Ag), and gold (Au); calcium carbonate (CaCO ₃ ), aluminum oxide (Al ₂ O ₃ ), aluminum hydroxide (Al(OH) ₃ ), silicon carbide (SiC); inorganic powders such as boron nitride (BN) and aluminum nitride (AlN); And, as the carbon material, at least one selected from organic powders such as graphite, graphene, carbon nanotubes (CNT) and carbon nanofibers (CNF) may be used. In addition, the thermally conductive component preferably includes one or more carbon materials selected from the group consisting of graphite, graphene, carbon nanotubes (CNT) and carbon nanofibers (CNF) among the materials listed above.

As a preferred example, the adhesive layer may be formed through a heat dissipation adhesive layer forming composition comprising a carbon-based filler as an adhesive component, a curing agent, and a thermal conductive component and a physical property enhancing component for improving heat dissipation and adhesion, and the carbon-based filler is heat dissipating Contained in an amount of 0.1 to 60% by weight of the adhesive layer forming composition, the physical property enhancing component is included in an amount of 0.01 to 20 parts by weight based on 100 parts by weight of the carbon-based filler, and the remaining amount may be an adhesive component and a curing agent, in which case the curing material may be included in an amount of 5 to 300 parts by weight based on 100 parts by weight of the adhesive component, but is not limited thereto, and the composition ratio may be changed according to the purpose.

The adhesive component may preferably be an epoxy resin, and non-limiting examples thereof include a glycidyl ether type epoxy resin, a glycidylamine type epoxy resin, a glycidyl ester type epoxy resin, and a linear aliphatic type (linear). Aliphatic) epoxy resins, cyclo aliphatic epoxy resins, heterocyclic-containing epoxy resins, substituted epoxy resins, naphthalene-based epoxy resins and at least one selected from the group consisting of derivatives thereof may be included.

When the curing agent includes an epoxy resin as an adhesive component, it may include any one or more of a polyhydric hydroxy compound, an aliphatic amine, an aromatic amine, an acid anhydride-based curing agent, and a latent curing agent. The carbon-based filler is one selected from the group consisting of single-walled carbon nanotubes, double-walled carbon nanotubes, multi-walled carbon nanotubes, graphene, graphene oxide, graphene nanoplates, graphite, carbon black, and carbon-metal composites. may include more than one.

The physical property enhancing component may preferably include a silane-based compound, wherein the silane-based compound is 3-[N-anyl-N-(2-aminoethyl)]aminopropyltrimethoxysilane, 3-(N- anyl-N-glycidyl)aminopropyltrimethoxysilane, 3-(N-anyl-N-methacrylonyl]aminopropyltrimethoxysilane, 3-glycidyl oxypropylmethylethoxysilane, N, N-Bis[3-(trimethoxycinyl)propyl]methacrylamide, γ-glycidoxytrimethyldimethoxysilane, 3-glycidyloxypropyltrimethoxysilane, 3-glycidyloxypropyltrie Toxysilane, 3-glycidyloxypropylmethylmethoxysilane, beta (3,4-epoxycyclohexyl)ethyltrimethoxysyl, 3-methacryloxypropyltrimethoxysilane, 3-glycidoxypropylmethyldime Toxysilane, heptadecafluorodecytrimethoxysilane, 3-methacryloxypropylmethyldimethoxysilane, 3-methacryloxypropyltris(trimethylsiloxy)silane, methyltris(dimethylsiloxy)silane, 3-amino It may include at least one selected from the group consisting of propyltriepoxy silane, 3-mercaptopropyltrimethoxy silane, and N-(β-aminoethyl)-γ-aminopropyltrimethoxysilane.

Here, the composition for forming a heat dissipation adhesive layer is other than a dispersant, a dispersion stabilizer, a leveling agent, a pH adjuster, an ion trapping agent, a viscosity modifier, a thixotropic agent, an antioxidant, a heat stabilizer, a light stabilizer, an ultraviolet absorber, a colorant , one or two or more kinds of various additives such as a dehydrating agent, a flame retardant, an antistatic agent, an antifungal agent, and a preservative may be added. As the various additives described above, those known in the art may be used, and thus, the present invention is not particularly limited. In addition, the heat dissipation adhesive layer forming component may further include a solvent, and a conventional solvent suitable for this may be selected according to the selected adhesive component, so that the present invention is not particularly limited thereto.

On the other hand, the metal protective film 120 ' according to the present invention, as shown in FIG. 5, a base layer 123 made of a metal material for heat dissipation, and a coating layer that is radiation-coated on at least one surface of the base layer 123 ( 124) may be included. Here, the coating layer 124 may be a ceramic having a particle size of a nano size or a metal oxide material including carbon black.

The coating layer 124 increases the emissivity, thereby further enhancing the heat dissipation effect of the metal protective film 120 ′.

In addition, the metal protective film 120 may form an oxide film by oxidizing the surface of a metal material constituting the metal protective film 120 through a blackening process. For example, when the metal material is copper, the oxide film may be an oxide film such as CuO and Cu ₂ O.

Through this, it is possible to prevent corrosion to minimize cracking, to improve adhesion and adhesion according to an increase in surface area, and to increase the emissivity of the material itself to further enhance the heat dissipation characteristics without increasing the overall thickness.

In addition, in the case of the oxide film formed on the surface of the metal layer, it acts as an insulating layer and increases the overall resistance value, thereby reducing the generation of eddy currents during wireless charging, thereby increasing the charging efficiency. Here, the blackening treatment may be performed using a chemical, may be performed through heat treatment, or may be performed through plasma treatment.

On the other hand, in the metal protective film 120 according to the present invention, at least one slit 122 having a predetermined length is formed therethrough as shown in FIGS. 1 to 4D to increase the resistance of the metal protective film 120 . It is also possible to increase the charging efficiency by suppressing the generation of eddy currents during wireless charging.

Here, the slits 122 may be provided entirely or partially on the metal protective film 120 , and when a plurality of the slits 122 are provided, the plurality of slits 122 are arranged in a predetermined pattern. may be or may be arranged in a random form.

At this time, the slit 122 is formed in an area corresponding to the wireless charging antenna 12 among the antenna units 10 disposed on one surface of the shielding unit 100 , and constitutes the wireless charging antenna 12 . formed in a direction perpendicular to the pattern.

That is, the slit 122 is perpendicular to the longitudinal direction of the pattern constituting the wireless charging antenna 12 when the wireless charging antenna 12 is formed in a rectangular pattern as shown in FIG. 3A . It may be provided to have a predetermined length in the direction.

In addition, the slit 122 is a direction perpendicular to the tangent line of the pattern constituting the wireless charging antenna 12 when the wireless charging antenna 12 is formed in a circular pattern as shown in FIG. 3b . It may be formed to have a certain length.

In addition, although not shown, when the wireless charging antenna 12 is provided in a form having both a straight section and a curved section, the slit formed in the straight section constitutes the wireless charging antenna 12 as shown in FIG. 3A . It is provided to have a predetermined length in a direction perpendicular to the longitudinal direction of the pattern, and the slit formed in the curved section is constant in a direction perpendicular to the tangent line of the pattern constituting the wireless charging antenna 12 as shown in FIG. 3b. formed to have a length.

The slit 122 may be provided in various shapes as shown in FIGS. 4A to 4D . That is, the slit 122 may be provided in the form of a cutout 122a extending inward by a predetermined length from the edge of the metal protection film 120 (see FIGS. 4c and 4d ), and the metal protection film ( It may be provided in the form of a through hole 122b penetrating the inside of the 120 (see FIGS. 4A and 4B ), and the cutout 122a and the through hole 122b may be provided in a combined form ( not shown).

On the other hand, the magnetic field shielding sheet corresponds to the plurality of antennas (12, 13, 14) when the antenna unit (10) is composed of a plurality of antennas (12, 13, 14) performing different roles, the corresponding antenna It may be provided with different types of sheets 211 and 212 to enhance the characteristics of the .

For example, when the antenna unit 10 includes a wireless charging antenna 12 and an NFC antenna 14 operating in different frequency bands, the magnetic field shielding sheets 210 , 210 ′, 210 ″ have a predetermined frequency. It may be composed of a first sheet 211 and a second sheet 212 having different characteristics so as to improve the characteristics of the corresponding antenna in each band, wherein the antenna unit 10 is an MST antenna 13 ) may be further included.

Specifically, the first sheet 211 is disposed in an area corresponding to the wireless charging antenna 12 so as to enhance the characteristics of the wireless charging antenna 12 , and the second sheet 212 is ) are respectively disposed in the area corresponding to the NFC antenna 14 so as to increase the characteristics of the NFC antenna 14 .

Here, the first sheet 211 is provided to have an area including the wireless charging antenna 12 , and the second sheet 212 is provided to have an area including the NFC antenna 14 . . In addition, the first sheet 211 may or may not include an area directly above the MST antenna 13 when the MST antenna 13 is provided on the outside of the wireless charging antenna 12 . It should be noted that there may be

In this case, the magnetic field shielding sheets 210 , 210 ′, 210 ″ may be provided in a form in which the first sheet 211 is laminated on one surface of the second sheet 212 (see FIG. 7A ), and the second sheet ( A first sheet 211 having the same thickness as that of 212 may be provided in a form inserted into the second sheet 212 (see FIG. 7B ), and the first sheet 211 having a thinner thickness than that of the second sheet 212 may be provided. The sheet 211 may be provided in a form inserted into one surface of the second sheet 212 (see FIG. 7C ).

Meanwhile, the first sheet 211 and the second sheet 212 may be provided to have different magnetic permeability or different saturation magnetic fields in a predetermined frequency band, and the first sheet 211 and the second sheet 212 in a predetermined frequency band. When the magnetic permeability of the second sheet 212 is the same, the investment loss rate may be provided to have different values.

Specifically, the first sheet 211 may be provided to have a relatively higher magnetic permeability than the second sheet in a frequency band of 100 to 300 kHz, which is a low frequency band, and the second sheet in a frequency band of 100 to 300 kHz. It may be provided to have a relatively larger saturation magnetic field, and when the first sheet 211 and the second sheet 212 have the same magnetic permeability in a frequency band of 100 to 300 kHz, the investment of the first sheet 211 is The loss ratio may be provided to have a relatively smaller value than the investment loss ratio of the second sheet 212 .

For example, the first sheet 211 may be a ribbon sheet of an amorphous alloy or nano-crystalline alloy may be used, and the second sheet 212 may be a ferrite sheet.

This is because the ribbon sheet of the amorphous alloy or nano grain alloy has a relatively higher magnetic permeability than the ferrite sheet in the frequency band of 100 to 300 kHz. The alternating magnetic field is induced to the side of the first sheet 211 having a relatively high magnetic permeability, so that the wireless power signal can be received with high efficiency toward the wireless charging antenna 12 disposed on the side of the first sheet 211 . be able to do

On the other hand, when the magnetic field shielding sheets 210, 210', 210" are implemented as a wireless power receiving module and a permanent magnet is provided in the wireless power transmitting module, the magnetic field shielding sheets 210, 210', 210" are formed by the permanent magnet. It is also required to shield all DC magnetic fields. However, since the direct current magnetic field is greater than the effect of the alternating magnetic field generated by the antenna unit 10 on the magnetic field shielding sheets 210, 210', 210", the magnetic saturating the magnetic field shielding sheet reduces the performance as a magnetic field shielding sheet, or This causes a problem in which the power transmission efficiency is rapidly reduced.

Therefore, it is necessary to block the magnetic saturation by the permanent magnet provided in the wireless power transmission module. For this reason, since the ribbon sheet of the amorphous alloy or nano-grain alloy has a relatively larger saturated magnetic field than the ferrite sheet in the frequency band of 100 to 300 kHz, the first sheet disposed in the area corresponding to the wireless charging antenna 12 Reference numeral 211 prevents magnetization by a permanent magnet in a frequency band of 100 to 300 kHz in which wireless charging is performed, thereby enabling smooth wireless charging.

In addition, even if the first sheet 211 and the second sheet 212 have the same magnetic permeability in a frequency band of 100 to 300 kHz, the investment loss ratio of the first sheet 211 is the investment loss ratio of the second sheet 212 . If it is provided to have a value relatively smaller than the loss rate, as a result, the loss of permeability due to the investment loss rate during wireless charging operation is reduced.

Accordingly, an alternating magnetic field generated according to power transmission at a frequency of 100 to 300 kHz transmitted from the wireless power transmission module is induced toward the first sheet 211 having a relatively high magnetic permeability, so that the region corresponding to the first sheet 211 . It is possible to induce the wireless power signal to be received with high efficiency toward the wireless charging antenna 12 disposed on the side.

Meanwhile, the second sheet 212 may be provided to have a relatively higher magnetic permeability than the first sheet at a high frequency of 13.56 MHz, and the first sheet 211 and the second sheet 212 at a frequency band of 13.56 MHz. ) may be provided such that the investment loss ratio of the second sheet 212 has a relatively smaller value than the investment loss ratio of the first sheet 211 when they have the same magnetic permeability.

For example, the first sheet 211 may be a ribbon sheet of an amorphous alloy or nano-crystalline alloy may be used, and the second sheet 212 may be a ferrite sheet.

This is because the ferrite sheet has a relatively higher magnetic permeability than the ribbon sheet of an amorphous alloy or nano-grain alloy in the frequency band of 13.56 MHz. When near field communication (NFC) is performed, a 13.56 MHz high-frequency signal generated from an antenna installed in an RF reader The alternating magnetic field generated by the is induced toward the second sheet 212 having a relatively high magnetic permeability, so that the high-frequency signal is received with high efficiency toward the NFC antenna 14 disposed in the area corresponding to the second sheet 212. can be induced to become.

In addition, even if the first sheet 211 and the second sheet 212 have the same magnetic permeability at a frequency of 13.56 MHz, the investment loss ratio of the second sheet 212 is higher than the investment loss ratio of the first sheet 211 . If it is provided to have a relatively small value, as a result, the loss of the magnetic permeability due to the investment loss during near field communication (NFC) is reduced. Accordingly, the alternating magnetic field generated by the 13.56 MHz high frequency signal generated by the RF reader is induced toward the second sheet 212 having a relatively high magnetic permeability, so that the NFC antenna 14 disposed on the second sheet 212 side. ) to allow high-frequency signals to be received with high efficiency.

Here, although it has been described that a ribbon sheet of an amorphous alloy or a nanocrystalline alloy is used as the first sheet 211, and a ferrite sheet is used as the second sheet 212, it is not limited thereto, and magnetic permeability, saturation magnetic field and investment It should be noted that the materials of the first sheet 211 and the second sheet 212 may be variously changed as long as the loss rate satisfies a relative condition with respect to each other in the frequency band.

For example, the first sheet 211 and the second sheet 212 may be made of the same material having different magnetic permeability in a frequency band of 100 to 300 kHz and/or a frequency of 13.56 MHz, and the first sheet 211 ), a ferrite sheet may be used, and an amorphous alloy or a ribbon sheet of a nano-crystalline alloy may be used as the second sheet 212 . This is because, even if made of the same material, it can be manufactured to have different characteristics (permeability, saturation magnetic field, permeability, etc.) through changes in various conditions such as heat treatment temperature and number of laminations.

In addition, when at least one of the first sheet 211 and the second sheet 212 is a ribbon sheet of an amorphous alloy or a nano-crystalline alloy, a single-layer ribbon sheet may be used, but as shown in FIG. Likewise, the first sheet 211 and/or the second sheet 212 may be configured in a form in which a plurality of ribbon sheets of amorphous alloy or nano-crystalline alloy are stacked.

The above-described shielding unit 100, 200, 200 ', 200" for wireless charging according to an embodiment of the present invention may be applied to the Qi method, and a portion of the magnetic force line generated from the permanent magnet is PMA induced through an attractor (not shown). It should be noted that it may be applied to wireless charging of the method. In addition, the shielding unit (100, 200, 200 ', 200 ") for wireless charging according to an embodiment of the present invention may be applied to a magnetic resonance method in which wireless charging is performed at a frequency of 6.78 MHz. make it clear that

As an example, the shielding unit 100 for wireless charging according to an embodiment of the present invention is a wireless power charging module 1 including a shielding unit 100 and an antenna unit 10 as shown in FIGS. 8 and 9 . ) can be applied to

Here, the wireless power charging module 1 may be a wireless power transmission module that transmits a wireless signal to the electronic device, or a wireless power reception module that receives a wireless signal from the wireless power transmission module.

Although one embodiment of the present invention has been described above, the spirit of the present invention is not limited to the embodiments presented herein, and those skilled in the art who understand the spirit of the present invention can add components within the scope of the same spirit. , changes, deletions, additions, etc. may easily suggest other embodiments, but this will also fall within the scope of the present invention.

1: wireless power charging module 10: antenna unit
11: circuit board 12: antenna for wireless charging
13: antenna for MST 14: antenna for NFC
100,200,200',200" : Shielding unit for wireless charging
110,110',210,210',210" : magnetic shielding sheet
111a, 111b, 111c: Ribbon sheet of amorphous alloy or nano-crystalline alloy
111d: adhesive layer 211: first sheet
212: second sheet 120: metal protective film
122: slit 124: coating layer
130: adhesive layer 140: protective film

Claims (14)

As a shielding unit for wireless charging disposed on one side of the antenna unit,
magnetic field shielding sheet; and
The magnetic field shielding sheet is made of a metal thin film to perform a heat dissipation function for emitting heat to the outside together with a protective function to protect the magnetic field shielding sheet, and the magnetic field shielding surface opposite to one side on which the antenna unit is disposed in the magnetic field shielding sheet a metal protective film disposed on the exposed surface of the sheet and directly attached to the exposed surface of the magnetic field shielding sheet through an adhesive layer having thermal conductivity; and
At least one slit which is formed in an area corresponding to the wireless charging antenna disposed on one side of the magnetic field shielding sheet and penetrates through the metal protective film to suppress the generation of eddy currents by increasing the resistance of the metal protective film. including,
The slit is formed to have a predetermined length in a direction perpendicular to the longitudinal direction of the pattern constituting the wireless charging antenna, or is formed to have a predetermined length in a direction perpendicular to the tangent line of the pattern constituting the wireless charging antenna, ,
The metal protective film is a shielding unit for wireless charging that is provided to have a thickness of 1/9 to 1/3 with respect to the thickness of the magnetic shielding sheet. The method of claim 1,
The metal protective film is a metal thin film having thermal conductivity of 200 W/m · K or more, and is directly attached to one side of the magnetic field shielding sheet through an adhesive layer having thermal conductivity. The method of claim 1,
The metal protective film is a shielding unit for wireless charging of aluminum foil or copper foil. The method of claim 1,
The metal protective film is a wireless charging shielding unit comprising a base layer made of a metal material, and a coating layer that is radiation-coated on at least one surface of the base layer. 5. The method of claim 4,
The coating layer is a shielding unit for wireless charging comprising at least one selected from ceramic or metal oxide. delete delete delete delete delete delete delete delete delete

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