JP4962634B1 - Method for manufacturing contactless charging module - Google Patents

Abstract

By using a magnetic sheet with a slit, the magnetic sheet is prevented from being damaged and adversely affecting its characteristics, and a strong adhesion between the magnetic sheet having a slit and a conductor is achieved. An object is to provide a non-contact charging module.
A planar coil part 2 in which a conducting wire is wound in a spiral shape and a magnetic sheet 3 provided so as to face the planar coil part 2 are provided, and a plurality of slits 36 are formed on the surface of the magnetic sheet 3. The planar coil portion 2 is bonded to the surface of the magnetic sheet 3 on which the slits 36 are formed.
[Selection] Figure 3

Description

  The present invention relates to a non-contact charging module and a non-contact charging device having a planar coil portion made of a spiral copper wire and a magnetic sheet.

  In recent years, many devices that can charge the main device in a non-contact manner with a charger have been used. In this method, a power transmission coil is arranged on the charger side, a power reception coil is arranged on the main device side, and electromagnetic induction is generated between the two coils to transmit power from the charger side to the main device side. It has also been proposed to apply a mobile terminal device or the like as the main device.

  The non-contact charging module used for the main device such as the portable terminal device and the charger is required to be thin and small. In order to meet this demand, it is conceivable that this type of non-contact charging module includes a planar coil portion as a power transmission coil or a power reception coil, and a magnetic sheet, as in (Patent Document 1). Moreover, regarding the magnetic sheet, there is a sheet having a flexibility by inserting a slit as in (Patent Document 2).

JP 2006-42519 A Japanese Patent No. 4400509

  The magnetic sheet employed in the non-contact charging module described in (Patent Document 1) is a flat magnetic sheet and has a problem that it does not have flexibility. For this reason, depending on how the non-contact charging module is handled, the magnetic sheet is damaged, and the characteristics are adversely affected.

  For this reason, mounting a magnetic sheet having flexibility by inserting a slit described in (Patent Document 2) on this type of non-contact charging module has been studied. However, since the adhesion between the conducting wire and the magnetic sheet is due to point contact, there is a problem of strong adhesion between the slit-containing magnetic sheet and the conducting wire.

  Therefore, in view of the above problems, the present invention employs a flexible magnetic sheet with slits to prevent the magnetic sheet from being damaged and having an adverse effect on the characteristics. Another object of the present invention is to provide a non-contact charging module that achieves strong adhesion between a magnetic sheet and a conductive wire.

In order to solve the above-mentioned problem, the present invention forms a plurality of cuts on one surface of a ferrite sheet, and then the other surface which is the surface opposite to the one surface and the one surface of the ferrite sheet. And a sheet for holding the ferrite sheet, and then firing the ferrite sheet, and then pressing the one surface of the ferrite sheet from above to form the ferrite sheet in the plurality of cuts. Is formed on the one side of the ferrite sheet, and then the planar coil portion around which the conductive wire is wound is bonded to the ferrite sheet. In the pressurizing step, bonding is performed avoiding the protrusion formed at the position corresponding to the slit on the other surface. And as the manufacturing method of the non-contact charging module to symptoms.

  According to the present invention, by adopting a magnetic sheet having flexibility, the magnetic sheet is prevented from being damaged and adversely affecting the characteristics, and a strong adhesion between the slit magnetic sheet and the conductive wire is prevented. It is possible to provide a non-contact charging module that achieves the above.

Assembly drawing of the non-contact charging module in the embodiment of the present invention The conceptual diagram of the non-contact charge module in embodiment of this invention The figure which shows the process order which adhere | attaches the magnetic sheet and flat coil of the non-contact charge module in embodiment of this invention

According to the first aspect of the present invention, a plurality of cuts are formed on one surface of the ferrite sheet, and thereafter, the one surface of the ferrite sheet and the other surface that is the surface opposite to the one surface. A sheet holding the ferrite sheet is bonded to each, and then the ferrite sheet is fired, and then the ferrite sheet is divided into the plurality of cuts by pressing the one surface of the ferrite sheet from above. Forming a slit to be bonded, and then bonding the planar coil portion around which the conductive wire is wound via the sheet to the ferrite sheet on the one surface side of the ferrite sheet, In the pressurizing step, bonding is performed while avoiding the protrusion formed at the position corresponding to the slit on the other surface. A method of manufacturing a contact charging module, in which a non-contact charging module adheres a coil to a magnetic sheet that does not have protrusions, avoiding the surfaces of protrusions that are formed during the manufacture of the magnetic sheet. In addition, the coil floating that occurs when the protrusion is bonded to the surface does not occur. As a result, the magnetic sheet and the coil can be securely and flatly bonded, power transmission of the non-contact charging module can be reliably performed, and characteristic fluctuations can be reduced against damage such as vibration and dropping. be able to.

Further, it is possible to adhere reliably and flat the magnetic sheet and coil, with the power transmission of the non-contact charging module can be reliably performed, achieving thinner and smaller non-contact charging module Can do.

Further, it is possible to obtain a magnetic sheet merely resilient easy.

Further, it is possible to adhere reliably and flat the magnetic sheet and coil, with the power transmission of the non-contact charging module can be reliably performed, to reduce the characteristic variation with respect to damage of vibration and falls be able to.

(Embodiment)
Hereinafter, embodiments of the present invention will be described with reference to the drawings. FIG. 1 is an assembly diagram of a contactless charging module according to an embodiment of the present invention. FIG. 2 is a diagram showing a process sequence for bonding the magnetic sheet and the planar coil of the non-contact charging module according to the embodiment of the present invention. 3A and 3B are conceptual diagrams of the non-contact charging module according to the embodiment of the present invention, in which FIG. 3A is a top view, FIG. 3B is a cross-sectional view viewed from the AA ′ direction in FIG. (c) And (d) is sectional drawing seen from the BB 'direction of Fig.3 (a). In FIG. 2, the wire diameters of the slits provided in the magnetic sheet 3 and the conductors of the coil 21 are very close to each other. However, the wire diameters of the conductors are actually about 0.25 to 0.35 mm and the slits are about 2 mm. It is. Of course, it is not limited to this value.

  As shown in FIG. 1, the contactless charging module 1 of the present invention includes a planar coil portion 2 in which a conductive wire is wound in a spiral shape, and a magnetic sheet provided so as to face the surface of a coil 21 of the planar coil portion 2. 3.

  The planar coil unit 2 includes a coil 21 in which a conductor is wound in a radial direction so as to draw a vortex on the surface, and terminals 22 and 23 provided at both ends of the coil 21. The coil 21 is obtained by winding a conducting wire in parallel on a plane, and a surface formed by the coil is called a coil surface. In addition, the thickness direction is a stacking direction of the planar coil portion 2 and the magnetic sheet 3. In the present embodiment, the coil 21 is wound outward from an inner diameter of 20 mm in diameter, and the outer diameter is 30 mm. That is, the coil 21 is wound in a donut shape. The coil 21 may be wound in a circular shape or may be wound in a polygonal shape.

  In addition, since the conducting wires are wound so as to leave a space between each other, the stray capacitance between the upper conducting wire and the lower conducting wire is reduced, and the AC resistance of the coil 21 can be kept small. Moreover, the thickness of the coil 21 can be suppressed by winding so that space may be packed.

  The magnetic sheet 3 is provided in order to improve the power transmission efficiency of non-contact charging using electromagnetic induction action and to reduce magnetic flux leakage to the back side of the magnetic sheet 3.

  The magnetic sheet 3 used in this embodiment will be described with reference to FIG. In particular, the reason why the protrusion 50 is formed on the back surface of the surface on which the cut 35 of the magnetic sheet 3 is formed will be described in detail.

  First, in the first step (FIG. 2 (a)), an incision 35 having a depth of 0.1 mm is formed with a cutter blade at a pitch of 2.4 mm and 2.4 mm on the upper surface of a 0.6 mm thick ferrite sheet. Provide.

  In the second step (FIG. 2B), an acrylic adhesive (trade name: 9313B, Sumitomo) having a thickness of 0.06 mm is formed on both surfaces (FIG. 2A surface, B surface) of the magnetic sheet 3 in which the cuts 35 are formed. 3M [registered trademark]), and a PET adhesive sheet 40 is adhered and held.

  In the third step (FIG. 2 (c)), when the magnetic sheet 3 is placed on the adhesive sheet 40 and divided by pressing with a roller or the like from above after baking (breaking), a V-shape is formed as shown in the figure. The vertical and horizontal slits 36 are formed (not shown in the figure, but the slits are formed vertically and horizontally). The V-shaped vertical and horizontal slits 36 allow the magnetic sheet 3 to have flexibility and are difficult to break. In addition, although the cut | notch 35 is made in a square, the rectangle containing a square may be sufficient. By making the cut 35 into a rectangular shape, the magnetic sheet 3 can have flexibility in two vertical and horizontal directions.

  In the third step, minute fragments are generated when the magnetic sheet 3 is pressed from above with a roller or the like and divided into vertical and horizontal slits 36. When the minute fragments are pushed by the rollers, they are pushed out below the vertical and horizontal slits 36. As a result, a large number of protrusions 50 are generated at positions corresponding to the vertical and horizontal slits 36 on the surface (surface B in FIG. 2) opposite to the surface into which the cutter blade is inserted (surface A in FIG. 2).

  In the fourth step (FIG. 2D), the A surface where the protrusion 50 is not generated and the coil 21 are bonded using an adhesive. In this way, the coil 21 is bonded to the A surface of the magnetic sheet 3 where no protrusion is generated while avoiding the B surface where the protrusion 50 is generated, so that the inclination of the surface of the coil 21 does not occur and there is a protrusion. The coil 21 is not lifted when it is bonded to the surface. As a result, the magnetic sheet 3 and the coil 21 can be securely and flatly bonded, and the power transmission of the non-contact charging module 1 can be reliably performed.

  Also, a plurality of cuts are made on the A surface of the magnetic sheet 3, a tape is applied to both surfaces (A surface and B surface) of the magnetic sheet 3, and the surface (A surface) with the cuts 35 is pressed to apply the vertical and horizontal slits 36. Therefore, it is possible to prevent small fragments generated when the cut 35 is made in the magnetic sheet 3 from being confined in the magnetic sheet 3 and adhere to the surface (A surface side) of the magnetic sheet 3.

  Next, the effect when the vertical and horizontal slits 36 are provided in the magnetic sheet 3 will be described. In the case of the planar coil 2 using the magnetic sheet 3 without vertical and horizontal slits, the L value after giving damage such as vibration to the magnetic sheet 3 is about 5% as compared with the L value of the normal product (inductance value of the coil 21). In the case of the planar coil 2 using the magnetic sheet 3 having the vertical and horizontal slits 36, the L value after giving the same damage to the magnetic sheet 3 hardly changes. Thus, by providing the vertical and horizontal slits 36 in the magnetic sheet 3, changes in the L value of the planar coil 2 with respect to damage such as vibration and dropping can be reduced.

  In addition, although the thickness of the magnetic sheet 3, the depth of blade insertion to the magnetic sheet 3, and the space | interval of the vertical / horizontal slit 36 described the typical numerical value by embodiment, it is not necessarily limited to this. The thickness of the magnetic sheet 3 is 0.1 to 1 mm, the depth of blade insertion into the magnetic sheet 3 is preferably less than half of the thickness of the magnetic sheet 3, and the interval between the vertical and horizontal slits 36 is preferably 5 mm or less. In addition, as shown in FIG. 2, the magnetic sheet 3 has V-shaped vertical and horizontal slits 36 formed vertically and horizontally at intervals of 2 mm in the thickness direction of the magnetic sheet in order to provide flexibility of the sheet. May be any shape as long as it is formed in a groove shape, for example, it may be U-shaped.

  Next, the non-contact charging module of the present invention will be described with reference to FIG. As shown in FIG. 3, the non-contact charging module 1 of the present invention includes a planar coil portion 2 in which a conducting wire is wound in a spiral shape, and a magnet provided so as to face the surface of a coil 21 of the planar coil portion 2. A sheet 3 is provided. The coil 21 of the planar coil portion 2 is bonded to the surface of the magnetic sheet 3 where the protrusions 50 are not generated using an adhesive.

  In addition, although the cross section of the coil 21 is a circular conducting wire, it may be a conducting wire having a square shape or the like. However, in the case of a conductor having a circular shape compared to a conductor having a rectangular cross section, a gap is formed between adjacent conductors, so that the stray capacitance between the conductors is reduced, and the AC resistance of the coil 21 can be kept small. it can.

  In addition, the coil 21 is wound in one stage rather than being wound in two stages in the thickness direction, so that the alternating current resistance of the coil 21 is lowered and transmission efficiency can be increased. This is because when a conducting wire is wound in two stages, stray capacitance is generated between the upper conducting wire and the lower conducting wire. Therefore, it is better to wind as many portions as possible in one stage, rather than winding the entire coil 21 in two stages. Moreover, it can reduce in thickness as the non-contact charge module 1 by winding in 1 step | paragraph. In addition, the loss in the coil 21 is prevented because the alternating current resistance of the coil 21 is low, and the power transmission efficiency of the contactless charging module 1 depending on the L value can be improved by improving the L value.

  Moreover, in this Embodiment, the inner diameter X inside the coil 21 shown in FIG. 3 is 10 mm-20 mm, and an outer diameter is about 30 mm. As the inner diameter x is smaller, the number of turns of the coil 21 can be increased in the contactless charging module 1 of the same size, and the L value can be improved.

  In addition, although the terminals 22 and 23 may be close to each other or may be arranged apart from each other, the non-contact charging module 1 is easier to mount if they are arranged apart.

  The central portion 32 of the magnetic sheet 3 is not necessarily convex. The same surface as the flat portion 31 may be used, or a concave shape or a hollow cylinder may be used. However, as the thickness of the magnetic sheet 3 is reduced, the L value of the planar coil 2 is reduced, the power transmission efficiency is lowered, and the effect of the magnetic shield is reduced.

  Further, as shown in FIG. 3D, the concave portion 33 of the magnetic sheet 3 may be a slit 34, and the concave portion 33 or the slit 34 is not necessarily required. However, as shown in FIGS. 3C and 3D, by providing the recess 33 or the slit 34, the lead wire from the winding end of the coil 21 to the terminal 23 (see FIGS. 3C and 3D). (Corresponding to a black circle) can be stored in the recess 33 or the slit 34, so that the thickness can be reduced. That is, the concave portion 33 or the slit 34 is formed so as to be substantially perpendicular to the end portion of the magnetic sheet 3 and overlap with the tangent line on the outer periphery of the central portion 32. By forming the recess 33 or the slit 34 in this way, the terminals 22 and 23 can be formed without bending the conducting wire. In this case, the length of the recess 33 or the slit 34 is about 15 mm to 20 mm. However, the length of the recess 33 or the slit 34 depends on the inner diameter of the coil 21. Further, the concave portion 33 or the slit 34 may be formed in a portion where the end of the magnetic sheet 3 and the outer periphery of the central portion 32 are closest. Thereby, the formation area of the recessed part 33 or the slit 34 can be suppressed to the minimum, and the transmission efficiency of the non-contact charging module 1 can be improved. In this case, the length of the recess 33 or the slit 34 is about 5 mm to 10 mm. In either arrangement, the inner end of the recess 33 or the slit 34 is connected to the center 32. Moreover, you may make the recessed part 33 or the slit 34 into another arrangement | positioning.

  That is, it is desirable that the coil 21 has a one-stage structure as much as possible. In that case, all the turns in the radial direction of the coil 21 are made into a one-stage structure, or one part is made into a one-stage structure and the other part is made into a two-stage structure It is possible to do. Therefore, one of the terminals 22 and 23 can be pulled out from the outer periphery of the coil 21, but the other must be pulled out from the inside. Accordingly, the portion around which the coil 21 is wound and the foot portion 24 always overlap in the thickness direction. Accordingly, the concave portion 33 or the slit 34 may be provided in the overlapping portion, and the foot portion 24 may be accommodated therein. The foot portion 24 refers to a portion from the end of winding of the coil 21 to the terminal 22 or 23. If it is the recessed part 33, since a through-hole and a slit are not provided in the magnetic sheet 3, it can prevent that a magnetic flux leaks and can improve the electric power transmission efficiency of the non-contact charge module 1. FIG. On the other hand, in the case of the slit 34, the magnetic sheet 3 can be easily formed. When it is the recessed part 33, as shown in FIG.3 (c), it is not limited to the recessed part 33 whose cross-sectional shape becomes a square shape, You may form circular arc shape or roundness.

  In the present embodiment, a Ni—Zn ferrite sheet, a Mn—Zn ferrite sheet, a Mg—Zn ferrite sheet, or the like can be used as the magnetic sheet 3. The ferrite sheet can reduce the AC resistance of the coil 21 as compared with the amorphous metal magnetic sheet.

  As shown in FIG. 3, the magnetic sheet 3 has at least a high saturation magnetic flux density material 3a and a high magnetic permeability material 3b laminated. Even when the high saturation magnetic flux density material 3a and the high magnetic permeability material 3b are not laminated, it is preferable to use the high saturation magnetic flux density material 3a having a saturation magnetic flux density of 350 mT or more and a thickness of at least 300 μm.

  It is desirable that the coil 21 has a one-stage structure as much as possible. In that case, all the turns in the radial direction of the coil should be a one-stage structure, or a part may be a one-stage structure and the other part a two-stage structure. Conceivable. Therefore, one of the terminals 22 and 23 can be pulled out from the outer periphery of the coil 21, but the other must be pulled out from the inside.

  That is, the portion around which the coil 21 is wound and the foot portion 24 always overlap in the thickness direction.

  Accordingly, the concave portion 33 or the slit 34 is provided in a straight line at the overlapping portion. Here, the recess 33 is a groove having a bottom as shown in FIG. 3C, and the slit 34 is a groove having no bottom as shown in FIG. 3D. The foot portion 24 of the coil 21 is positioned inside the recess 33 or the slit 34, and the portion where the coil 21 overlaps can be kept at the same height as the portion where the coil 21 does not overlap. Thereby, thickness reduction of the whole apparatus can be achieved. In particular, a linear recess 33 or slit that is parallel to the tangential line of the inner circumference of the coil 21 surface and extends at the shortest distance from the start or end of winding of the coil surface to the end of the magnetic sheet 3. 34. The concave tangent 33 or the slit 34 extends from the vicinity of the outer periphery of the inner peripheral circle of the coil 21 surface, and the concave portion 33 or the slit 34 is the inner periphery of the coil 21 surface. It is the tangent of the circumference of the inner circumference circle at a location approaching the outer circumference of the circle. By forming the straight portion 33b in this way, the terminals 22 and 23 can be formed without bending the conducting wire on the magnetic sheet 3.

  In addition, the magnetic sheet 3 has a recess 33 that is perpendicular to the tangent to the inner circumference of the coil 21 surface and extends at the shortest distance from the start or end of winding of the coil surface to the end of the magnetic sheet 3. Alternatively, the slit 34 may be formed. Thereby, the formation area of the recessed part 33 or a slit can be suppressed to the minimum, and the transmission efficiency of the non-contact charge module 1 can be improved. That is, by providing the concave portion 33 or the slit 34, a part of the magnetic sheet 3 is missing or thinned. Therefore, the magnetic flux leaks from the recess 33 or the slit 34, and the power transmission efficiency of the non-contact charging module may be somewhat reduced. Therefore, by reducing the formation area of the recess 33 to the minimum, it is possible to reduce the thickness while minimizing the leakage of magnetic flux and maintaining the power transmission efficiency of the non-contact charging device. In this case, the length of the straight portion 33b is about 5 mm to 10 mm. In addition, on the tangent line of the outer periphery of the convex portion 32, the shape is parallel to the end portion 3 a of the magnetic sheet 3 in order to provide the shortest distance to the end portion of the magnetic sheet 3. Note that the coil 21 may be wound in a polygonal shape, and in that case, the coil 21 may be perpendicular to the shape of the space formed by the inner end of the surface of the coil 21 or its tangent line. The concave portion 33 or the slit 34 may be provided in a straight line extending from the end point to the end of the magnetic sheet 3 at the shortest distance.

  In FIG. 3, the concave portion 33 or the slit 34 is parallel to one pair of opposing end sides of the rectangular magnetic sheet 3 and is perpendicular to the other pair of opposing end sides. This is because the magnetic sheet 3 of the present embodiment is square. However, the shape of the magnetic sheet 3 is not limited to a square, and various shapes such as a circle and a polygon can be considered. Therefore, for example, the shape of the magnetic sheet 3 is polygonal, and the concave portion 33 or the slit 34 is perpendicular to the side against which one end of the concave portion 33 or the slit 34 abuts. 33 or the length of the slit 34 in the longitudinal direction can be minimized. In particular, the shape of the magnetic sheet 3 is square, parallel to one pair of opposing end sides of the magnetic sheet 3 and perpendicular to the other pair of opposing end sides, In the rectangular magnetic sheet that is easy to use, the area of the recess 33 or the slit 34 can be minimized.

  From the above, the concave portion 33 or the slit 34 is provided in a portion where the coil 21 and the foot portion 24 overlap each other, and the surface of the coil 21 is provided on the flat portion 31. The concave portion 33 or the slit 34 may be provided to be somewhat longer or shorter, but it is preferable that at least 80% or more of the portion where the coil 21 and the foot portion 24 overlap can be covered.

  In FIG. 3, the magnetic sheet 3 is about 33 mm × 33 mm. The thickness d1 of the center part 32 shown in FIG.3 (c) is 0.2 mm. Further, the magnetic sheet 3 is laminated by setting the thicknesses of the high saturation magnetic flux density material 3a and the high magnetic permeability material 3b. The thickness d2 of the magnetic sheet 3 is 0.6 mm, the thickness d4 of the high saturation magnetic flux density material 3a is 0.45 mm, and the thickness d3 of the high magnetic permeability material 3b is 0.15 mm.

  Thus, since the coil 21 is adhered to the surface of the magnetic sheet 3 where no projection is generated while avoiding the surface where the projection 50 is generated, the surface of the coil 21 is not inclined, and there is a projection. The coil 21 is not lifted when it is bonded to the surface. As a result, the magnetic sheet 3 and the coil 21 can be securely and flatly bonded, and the power transmission of the non-contact charging module 1 can be reliably performed.

  Further, in the case of the planar coil 2 using the magnetic sheet 3 having no vertical and horizontal slits, the L value after giving damage such as vibration to the magnetic sheet 3 is reduced by about 5% compared to the L value of the normal product. In the case of the planar coil 2 using the magnetic sheet 3 having the slits 36, the L value after giving similar damage to the magnetic sheet 3 hardly changes. Thus, by providing the vertical and horizontal slits 36 in the magnetic sheet 3, the change in the L value of the planar coil 2 with respect to damage such as vibration and dropping can be reduced, and the change in power transmission of the non-contact charging module 1 is reduced. be able to.

  Next, the non-contact charging device provided with the non-contact charging module 1 of the present invention will be described. The non-contact power transmission device includes a charger including a power transmission coil and a magnetic sheet, and a main device including a power receiving coil and a magnetic sheet. The main device is an electronic device such as a mobile phone. The circuit on the charger side includes a rectifying / smoothing circuit unit, a voltage conversion circuit unit, an oscillation circuit unit, a display circuit unit, a control circuit unit, and the power transmission coil. The circuit on the main device side includes the power receiving coil, a rectifier circuit unit, a control circuit unit, and a load L mainly composed of a secondary battery.

  The power transmission from the charger to the main device is performed using an electromagnetic induction action between the power transmission coil of the charger on the primary side and the power receiving coil of the main device on the secondary side.

  Since the non-contact charging device of the present embodiment includes the non-contact charging module described above, the non-contact charging device is provided in a state in which the cross-sectional area of the planar coil portion is sufficiently secured to improve power transmission efficiency. It can be reduced in size and thickness.

  According to the non-contact charging module of the present invention, since the non-contact charging module can be thinned in a state in which the cross-sectional area of the planar coil portion is sufficiently secured, a portable terminal such as a mobile phone or a portable computer, It is useful as a non-contact charging module for various electronic devices such as portable devices such as video cameras.

DESCRIPTION OF SYMBOLS 1 Non-contact charge module 2 Planar coil part 21 Coil 22,23 Terminal 3 Magnetic sheet 31 Flat part 32 Convex part 33 Concave part 34 Slit 35 Cut 36 Vertical / horizontal slit 40 Adhesive sheet 50 Protrusion

Claims (1)

Form multiple cuts on one side of the ferrite sheet,
Thereafter, the sheet holding the ferrite sheet is bonded to each of the one surface of the ferrite sheet and the other surface which is the surface opposite to the one surface,
Then, firing the ferrite sheet,
Then, forming a slit to divide the ferrite sheet at the plurality of cuts by pressing the one surface of the ferrite sheet from above,
Then, on the one surface side of the ferrite sheet, by adhering a planar coil portion wound with a conductive wire through the sheet to the ferrite sheet,
The method for manufacturing a non-contact charging module, wherein the planar coil portion is bonded while avoiding a protrusion formed at a position corresponding to the slit on the other surface in the pressing step.

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