WO2011001812A1

WO2011001812A1 - Coil, coil producing method, and coil module

Info

Publication number: WO2011001812A1
Application number: PCT/JP2010/060023
Authority: WO
Inventors: 雅人野村
Original assignee: 株式会社村田製作所
Priority date: 2009-06-30
Filing date: 2010-06-14
Publication date: 2011-01-06

Abstract

Provided are a coil, a coil producing method, and a coil module, wherein a magnetic shield function can be enhanced on the entire surface of a spiral conductor other than the surface to be electromagnetically coupled, losses in the electromagnetic coupling can be reduced, and the production cost can be reduced. A coil (10) is provided with a spiral conductor (2) formed in the shape of a plate, and a plastic structure (3) in the shape of a plate which contains a magnetic material. The coil (10) contains the spiral conductor (2) biased toward one surface of the plastic structure (3). Further, a part of the spiral conductor (2) is exposed toward the outside on one surface of the plastic structure (3). Further, the coil module is comprised of the coil (10) and a circuit substrate electrically connected to the coil (10), to which a predetermined circuit for processing electric signals passing through the coil (10) is mounted.

Description

COIL, COIL MANUFACTURING METHOD, AND COIL MODULE

The present invention relates to a coil, a coil manufacturing method, and a coil module, and more particularly to a flat coil, a coil manufacturing method, and a coil module.

Wireless chargers that transmit power without contact and charge, RF-IDs (Radio Frequency Identification) for identifying and managing people and things with a small wireless chip, etc., have inductance characteristics of several μH to several tens A μH coil is used. In particular, in the wireless charger, a coil is used for each of the power transmission side device and the power reception side device, and efficient power transmission is performed between the coil of the power transmission side device and the coil of the power reception side device. . In order to perform power transmission, the power transmitting side device includes a coil module that electrically connects a coil and a circuit board on which a circuit including at least a power control circuit and an inverter circuit is mounted. Needs to include a coil module that electrically connects the coil and a circuit board on which a circuit including at least a rectifier circuit, a regulator circuit, and a charge control circuit is mounted.

Moreover, in order to perform efficient power transmission, it is possible to reduce electromagnetic coupling loss between the coil of the power transmission side device and the coil of the power reception side device, and to efficiently perform electromagnetic induction between the coils. As described above, it is necessary to further increase the inductance characteristics of each coil. In addition, when the magnetic flux of the spiral conductor constituting the coil leaks from a surface other than the electromagnetically coupled surface in each coil, the rechargeable battery connected to the coil in the power receiving device is affected by the leaked magnetic flux. It is necessary to increase the magnetic shield function of all surfaces other than the surface to be electromagnetically coupled.

Patent Documents

1 and 2 disclose conventional coils in which a magnetic sheet is provided on any surface other than the surface to be electromagnetically coupled. The coil disclosed in Patent Document 1 is housed in a coil housing portion of a wiring board, and a magnetic sheet is provided on the surface opposite to the surface to be electromagnetically coupled to enhance the magnetic shield function. In addition, the coil disclosed in Patent Document 2 has a coil formed on a flexible substrate in a doughnut-shaped groove provided on a pot-type core made of ferrite as a material, so that a surface other than the surface to be electromagnetically coupled is arranged. The magnetic shield function is increased. Patent Document 3 discloses a conventional coil module in which a coil and a circuit board are electrically connected. The coil module disclosed in Patent Document 3 includes a protective sheet in which a coil is accommodated in a hole, and a substrate on which the protective sheet covers each end of the magnetic sheet and the magnetic sheet is bonded and fixed.

JP 2008-205214 A JP 2005-260122 A JP 2009-22126 A

However, in the coil disclosed in Patent Document 1, since the magnetic sheet is attached to the surface opposite to the surface to be electromagnetically coupled, the magnetic shield function is lowered when the attaching position of the magnetic sheet is shifted from the predetermined position. There was a problem. Further, since the magnetic sheet is easily bent, the coil to which the magnetic sheet is attached is easily deformed when stress is applied. When the coil is deformed and the inductance characteristic of the coil is lowered, there is a problem that the loss of electromagnetic coupling may increase. Furthermore, since the magnetic sheet itself is expensive and requires a step of attaching the magnetic sheet to the coil, there is a problem that the manufacturing cost of the coil disclosed in Patent Document 1 is increased.

The coil disclosed in Patent Document 2 has a problem that a magnetic shield function cannot be sufficiently increased because a gap is generated between the coil and the pot-type core. In addition, since the coil disclosed in Patent Document 2 is formed by patterning a coil on a flexible substrate, it has lower inductance characteristics than a coil of a spiral conductor formed in the same size, and electromagnetic coupling loss. There was a problem that became larger. Furthermore, since the flexible substrate itself is expensive and requires a step of bending the flexible substrate and a step of attaching the flexible substrate to the groove, there is a problem in that the manufacturing cost of the coil disclosed in Patent Document 2 also increases. .

In the coil module disclosed in Patent Document 3, since the protective sheet containing the coil holds the magnetic sheet in a predetermined position by bonding and fixing the magnetic sheet to the substrate, the magnetic sheet for the coil accommodated in the protective sheet There has been a problem that the position of the magnetic field is shifted and the magnetic shield function is lowered. Moreover, since the protective sheet which accommodated the coil is easy to bend, when the stress is applied, the coil accommodated in the protective sheet is also easily deformed. When the coil is deformed and the inductance characteristic of the coil is lowered, there is a problem that the loss of electromagnetic coupling may increase. Furthermore, since the magnetic sheet itself is expensive, and a step of adhering and fixing the magnetic sheet to the substrate with a protective sheet is required to hold the magnetic sheet in a predetermined position, the coil module disclosed in Patent Document 3 is required. There was a problem that the manufacturing cost was high.

The present invention has been made in view of the above circumstances, and can enhance the magnetic shield function on all surfaces other than the surface to be electromagnetically coupled, can reduce the loss of electromagnetic coupling, and can be manufactured at a low cost. It aims at providing the coil which becomes cheap, the manufacturing method of a coil, and a coil module.

In order to achieve the above object, a coil according to a first aspect of the present invention includes a spiral conductor formed in a flat plate shape and a flat resin structure containing a magnetic material, and the conductor is the resin structure. Built in on one side.

Further, in the coil according to the second invention, in the first invention, a part of the conductor is exposed to the outside on the one surface side of the resin structure.

Further, in the coil according to the third invention, in the first or second invention, both ends of the wire drawn from the conductor are exposed to the outside on any one surface of the resin structure.

Further, in the coil according to the fourth invention, in the first or second invention, both ends of the wire drawn out from the conductor are exposed to the outside from a recess or projection provided on one surface of the resin structure. Yes.

The coil according to a fifth aspect of the present invention is the coil according to any one of the first to fourth aspects, wherein terminals that are electrically connected to both ends of the wire drawn from the conductor are provided on one surface of the resin structure. It is provided.

In order to achieve the above object, a coil according to a sixth aspect of the present invention includes a spiral conductor formed in a flat plate shape and a flat resin structure containing a magnetic material, and the resin structure includes: The first layer and the second layer are different in the content of the magnetic material, and the conductor is sandwiched between the first layer and the second layer.

In order to achieve the above object, a coil manufacturing method according to a seventh aspect of the present invention includes a step of placing a spiral conductor formed in a flat plate at a predetermined position of a mold, and a temperature at which the mold is softened. A step of filling a curable resin containing a magnetic material heated to a temperature, curing the curable resin filled in the mold, and forming a flat resin structure with the conductor biased to one side and built-in Including the step of.

Further, the coil manufacturing method according to the eighth aspect of the present invention is the seventh aspect of the present invention, further comprising positioning means for arranging the conductor at a predetermined position of the mold.

Further, the coil manufacturing method according to the ninth aspect of the present invention is the seventh or eighth aspect of the invention, further comprising pressing means for pressing the conductor against the mold.

A coil manufacturing method according to a tenth aspect of the invention is the ninth aspect of the invention, comprising a first mold and a second mold to be fitted, and at least one of the first mold and the second mold. A first protrusion as the positioning means, and at least one of the first mold and the second mold has a second protrusion as the pressing means, and the first protrusion The conductor is disposed at a predetermined position of the first mold or the second mold, and a part of the conductor is disposed on the first mold or the second mold based on the second protrusion. Press on.

In order to achieve the above object, a coil module according to an eleventh aspect of the present invention is a coil module according to any one of the first to sixth aspects, wherein the coil module is electrically connected to the coil and processes an electrical signal flowing through the coil. And a circuit board on which a circuit is mounted.

Further, in the coil module according to a twelfth aspect of the present invention, in the eleventh aspect, the circuit board is disposed outside a predetermined interference region that interferes with the magnetic flux of the conductor.

Also, in the coil module according to the thirteenth aspect of the present invention, in the eleventh or twelfth aspect, the circuit board is disposed on a surface opposite to the one surface of the resin structure in which the conductor is embedded with a bias.

The coil module according to a fourteenth aspect of the present invention is the coil module according to any one of the eleventh to thirteenth aspects, wherein the circuit board is spaced apart from the inside toward the outside of the conductor.

A coil module according to a fifteenth aspect of the present invention is the coil module according to any one of the eleventh to fourteenth aspects, wherein the circuit board is drawn out from the conductor exposed to the outside on any one surface of the resin structure. In contact with both ends of the wire, the coil is electrically connected.

The coil module according to a sixteenth aspect of the present invention is the coil module according to any one of the eleventh to fourteenth aspects, wherein the resin structure exposes both ends of the wire drawn from the conductor on one side to the outside. The circuit board has a second recess or a second protrusion provided with terminals that are electrically connected to both ends of the wire drawn from the conductor, and the first protrusion has the protrusion or the first recess. The coil and the circuit board are electrically connected by fitting the second recess or the first recess and the second protrusion.

Also, in the coil module according to a seventeenth aspect of the present invention, in any one of the eleventh to fourteenth aspects, the circuit board is built in the resin structure.

A coil module according to an eighteenth aspect of the invention is the coil module according to any one of the eleventh to seventeenth aspects, wherein the circuit board is mounted with a power receiving side circuit including at least a rectifier circuit, a regulator circuit, and a charge control circuit. .

In the coil module according to the nineteenth aspect of the invention, in any one of the eleventh to seventeenth aspects, the circuit board is mounted with a power transmission side circuit including at least a power control circuit and an inverter circuit.

Further, in the coil module according to a twentieth invention, in any one of the eleventh to nineteenth inventions, the resin structure is made of an insulating material.

In the first invention, since the conductor is built in the flat resin structure containing the magnetic material, the mechanical strength of the coil is improved, and the coil is prevented from being deformed by an external force, thereby suppressing the inductance of the coil. Can be prevented, and the loss of electromagnetic coupling can be reduced. In addition, since the conductor is embedded in one side of the resin structure (surface to be electromagnetically coupled), the magnetic material contained in the curable resin covering all surfaces other than the surface of the conductor to be electromagnetically coupled is resin. More than the magnetic material contained in the curable resin on one side of the structure, the magnetic flux of the conductor generated on all surfaces other than one side of the resin structure can be confined in the resin structure, and one side of the resin structure in the coil The characteristic of inductance in the direction can be improved.

In the second invention, since the conductor is partially exposed to the outside on the one surface (surface to be electromagnetically coupled) side of the resin structure, all the surfaces other than the electromagnetically coupled surface of the conductor contain the magnetic material. By covering the curable resin, the magnetic flux of the conductor generated on all surfaces other than one surface of the resin structure can be confined in the resin structure, and the inductance characteristics in the one surface direction of the resin structure in the coil are enhanced. The magnetic shield function on all surfaces other than one surface of the resin structure can be enhanced.

In the third invention, since both ends of the wire drawn from the conductor are exposed to the outside on any one surface of the resin structure, the coil and the circuit board can be easily electrically connected.

In the fourth aspect of the invention, since both ends of the wire drawn from the conductor have a recessed portion or a protruding portion exposed to the outside on any one surface of the resin structure, the coil and the circuit board can be easily electrically connected. Can be connected.

In the fifth invention, since the terminals that are electrically connected to both ends of the wire drawn from the conductor are provided on any one surface of the resin structure, the coil and the circuit board can be easily electrically connected. Can do.

In the sixth invention, even if the first layer and the second layer have the same thickness, the conductor is sandwiched between the first layer and the second layer having different magnetic material content ratios. When the content of the magnetic material of the layer is higher than the content of the magnetic material of the second layer and the conductor is embedded in the first layer, the content of the magnetic material on all surfaces other than the surface of the conductor that is electromagnetically coupled Can be covered with a higher curable resin, the magnetic flux of the conductor generated on all surfaces except one surface of the first layer can be confined in the first layer, and the inductance of the coil in the one surface direction of the first layer can be confined. In addition to improving the characteristics, it is possible to increase the magnetic shield function of all surfaces other than one surface of the first layer.

In the seventh invention, a spiral conductor formed in a flat plate shape is disposed at a predetermined position of the mold, and the mold is filled with a curable resin containing a magnetic material heated to a softening temperature. Since the filled curable resin is cured to form a flat resin structure with the conductor biased to one side, an expensive magnetic sheet, flexible substrate, etc. are not required, and the magnetic sheet is attached to the coil. The process of attaching, the process of bending the flexible board, and the process of attaching the flexible board to the groove are not required, so that the manufacturing cost is reduced.

In the eighth invention, since the positioning means for arranging the conductor at a predetermined position of the mold is provided, the position of the conductor in the resin structure can be accurately determined, and the inductance of the coil in one surface direction of the resin structure A coil with improved characteristics can be easily manufactured.

In the ninth invention, since the pressing means for pressing the conductor against the mold is provided, the conductor is prevented from being lifted from the mold when filled with the curable resin, and the resin structure in the coil in one surface direction is prevented. A coil with high inductance characteristics can be easily manufactured.

In the tenth invention, the conductor is disposed at a predetermined position of the first mold or the second mold based on the first protrusion, and a part of the conductor is disposed on the first mold or the second based on the second protrusion. Because it is pressed against the mold, the position of the conductor in the resin structure can be accurately determined, and the conductor from the mold is prevented from being lifted when filled with a curable resin. A coil with enhanced inductance characteristics in the direction can be easily manufactured.

In the eleventh aspect of the invention, since the conductor is embedded in the resin structure with a bias toward one surface (surface to be electromagnetically coupled), the magnetic material contained in the curable resin covering all surfaces other than the surface to be electromagnetically coupled to the conductor. Is more than the magnetic material contained in the curable resin on one surface of the resin structure, and the magnetic flux of the conductor generated on all surfaces other than the one surface of the resin structure can be confined in the resin structure. The characteristic of inductance in one direction of the resin structure can be enhanced.

In the twelfth invention, since the circuit board is disposed outside a predetermined interference area that interferes with the magnetic flux of the conductor, the circuit board does not interfere with the magnetic flux of the conductor, and the loss of electromagnetic coupling can be reduced. Here, the predetermined interference region refers to a region where the circuit board interferes with the magnetic flux of the conductor, and specifically refers to a region in a direction substantially perpendicular to the surface of the conductor formed in a flat plate shape. .

In the thirteenth invention, since the circuit board is arranged on the surface opposite to the one surface of the resin structure in which the conductor is embedded in a biased manner, the circuit board does not disturb the magnetic flux of the conductor and the loss of electromagnetic coupling is reduced. Can do.

In the fourteenth aspect, since the circuit boards are spaced apart from each other in the direction from the inside to the outside of the conductor, the circuit board does not hinder the magnetic flux of the conductor, and the loss of electromagnetic coupling can be reduced.

In the fifteenth aspect, since both ends of the wire drawn from the conductor on any one surface of the resin structure are exposed to the outside, the coil of the coil module and the circuit board can be easily electrically connected.

In the sixteenth aspect of the invention, the first protrusion or the first recess that exposes both ends of the wire drawn from the conductor on any one surface of the resin structure, and the terminals that are electrically connected to both ends of the wire drawn from the conductor Since the second recess or the second protrusion provided with each is fitted, the coil of the coil module and the circuit board can be easily electrically connected and the position of the circuit board relative to the resin structure is fixed. can do.

In the seventeenth aspect, since the circuit board is built in the resin structure, the work of attaching the circuit board to the resin structure is not required, and the manufacturing cost is reduced.

In the eighteenth aspect, since the power receiving circuit including at least the rectifier circuit, the regulator circuit, and the charge control circuit is mounted on the circuit board, the coil module can be reduced in size.

In the nineteenth invention, since the power transmission side circuit including at least the power control circuit and the inverter circuit is mounted on the circuit board, the coil module can be reduced in size.

In the twentieth invention, since the resin structure is made of an insulating material, eddy current generated in the resin structure can be reduced, and loss of electromagnetic coupling can be reduced.

A coil and a coil module according to the present invention include a spiral conductor formed in a flat plate shape and a flat resin structure containing a magnetic material, and the conductor is provided on one surface of the resin structure (a surface to be electromagnetically coupled). ), The magnetic shield function can be enhanced on all surfaces other than the electromagnetic coupling surface of the resin structure, and the electromagnetic coupling loss can be reduced.

The coil manufacturing method according to the present invention also includes a magnetic material that is disposed at a predetermined position of a mold and has a spiral conductor formed in a flat plate shape and is heated to a softening temperature in the mold. The cured curable resin is filled, the filled curable resin is cured, and a flat resin structure with a conductor biased to one side is formed, so that an expensive material is not necessary and a plurality of processes are performed. Since it is unnecessary, the manufacturing cost is reduced.

It is a perspective view of the coil which concerns on Embodiment 1 of this invention. FIG. 2 is a cross-sectional view taken along line AA of the coil shown in FIG. It is a flowchart for demonstrating the manufacturing method of the coil which concerns on Embodiment 1 of this invention. It is a top view of the upper metal mold | die and lower metal mold | die for manufacturing the coil which concerns on Embodiment 1 of this invention. FIG. 5 is a BB cross-sectional view of the upper mold and the lower mold shown in FIG. 4. It is a perspective view of the coil which concerns on Embodiment 2 of this invention. It is a perspective view of the structure which provided the terminal in the coil which concerns on Embodiment 2 of this invention. It is a perspective view of another structure which provided the terminal in the coil which concerns on Embodiment 2 of this invention. It is a perspective view of another structure of the coil which concerns on Embodiment 2 of this invention. It is a perspective view of another structure of the coil which concerns on Embodiment 2 of this invention. It is a perspective view of the structure which provided the terminal in the coil shown in FIG.10 (c). It is a perspective view of the structure where the terminal was incorporated in the resin structure of the coil which concerns on Embodiment 2 of this invention. It is a perspective view of another structure which incorporated the terminal in the resin structure of the coil which concerns on Embodiment 2 of this invention. It is a schematic diagram for demonstrating the method to manufacture the coil shown to Fig.13 (a). It is a perspective view of the coil which concerns on Embodiment 3 of this invention. FIG. 16 is a CC cross-sectional view of the coil shown in FIG. 15. It is a perspective view of the coil module which concerns on Embodiment 4 of this invention. FIG. 18 is a DD cross-sectional view of the coil module shown in FIG. 17. It is a perspective view which shows another structure of the coil of the coil module which concerns on Embodiment 4 of this invention, and a resin structure. It is the schematic for demonstrating the method to process the both ends of a wire so that it may follow the side surface of a recessed part. It is the schematic for demonstrating another method of processing so that the both ends of a wire may be along the side surface of a recessed part. It is a perspective view which shows another structure of the coil of the coil module which concerns on Embodiment 4 of this invention, and a resin structure. It is a top view of the coil module which concerns on Embodiment 5 of this invention. FIG. 24 is a cross-sectional view of the coil module shown in FIG. 23 taken along the line EE. It is a side view of the circuit module using the coil module which concerns on Embodiment 5 of this invention. It is a side view which shows another structure of the circuit module using the coil module which concerns on Embodiment 5 of this invention. It is a perspective view of the coil module which concerns on Embodiment 6 of this invention. FIG. 28 is a cross-sectional view of the coil module shown in FIG. 27 taken along the line FF.

Hereinafter, the coil, the coil manufacturing method, and the coil module according to the embodiment of the present invention will be specifically described with reference to the drawings. The following embodiments do not limit the invention described in the claims, and all combinations of characteristic items described in the embodiments are essential to the solution. It goes without saying that it is not limited.

The coil and coil module according to the embodiment of the present invention will be described with reference to a coil and a coil module used for non-contact power transmission such as a wireless charger. The coil and the coil module for the application may be used. In addition, the coils and coil modules used for non-contact power transmission include coils and coil modules used for power transmission side devices and coils and coil modules used for power reception side devices, but are not specified in the following description. As long as it is a coil and a coil module, it does not matter.

(Embodiment 1)
FIG. 1 is a perspective view of a coil according to Embodiment 1 of the present invention. 2 is a cross-sectional view taken along the line AA of the coil shown in FIG. As shown in FIG. 1, the coil 10 includes a spiral conductor 2 formed in a flat plate shape and a flat resin structure 3 containing a magnetic material.

The conductor 2 is formed in a flat plate shape by spiraling a conductive wire such as a copper wire. In order to draw the wire from the inside of the spiral conductor 2 formed in a flat plate shape, the drawn wire material needs to get over the flat plate portion of the spiral conductor 2. Therefore, the wire 21 drawn from the inside of the spiral conductor 2 has a portion that overlaps the flat plate portion of the spiral conductor 2. On the other hand, the wire 22 drawn from the outside does not have a portion that overlaps the flat plate portion of the spiral conductor 2. The outer shape of the conductor 2 is formed in a substantially circular shape, but may be formed in a substantially elliptical shape or a substantially rectangular shape.

The resin structure 3 is formed by flattening a curable resin obtained by kneading a magnetic material such as ferrite into powder. Further, the spiral conductor 2 is embedded in a biased manner toward the one surface (surface to be electromagnetically coupled) 31 that is one surface of the resin structure 3. That is, the thickness from the spiral conductor 2 to one surface 31 of the resin structure 3 is made thinner than the thickness from the spiral conductor 2 to the other surface 32 that is one surface of the resin structure 3. .

In particular, in the coil 10 according to the first embodiment, as shown in FIG. 2, one of the resin structures 3 is reduced by reducing the thickness from the spiral conductor 2 to one surface 31 of the resin structure 3. Part of the spiral conductor 2 is exposed to the outside on the surface 31 side. When a part of the spiral conductor 2 is exposed to the outside on the one surface 31 side, one surface (one surface 31 side) of the spiral conductor 2 exposed to the outside becomes a surface to be electromagnetically coupled, Since all surfaces other than the electromagnetically coupled surface of the spiral conductor 2 are covered with the curable resin containing the magnetic material, the magnetic flux of the spiral conductor 2 generated on all surfaces other than the one surface 31 is generated. It can be confined in the resin structure 3, and the characteristic of inductance in the direction of the one surface 31 of the resin structure 3 in the coil 10 is enhanced and the magnetic shield function of all surfaces other than the one surface 31 is enhanced. be able to.

Further, the portion where the wire 21 drawn out from the inside of the spiral conductor 2 and the flat plate portion of the spiral conductor 2 overlap is the convex portion 23. However, since the coil 10 according to the first embodiment incorporates the spiral conductor 2 in the resin structure 3 so as to embed the convex portion 23 in the resin structure 3, the convex portion 23 is the appearance of the coil 10. Does not affect. In the coil disclosed in Patent Document 1, since the magnetic sheet is attached to the surface of the spiral conductor on which the convex portion is formed (the surface opposite to the surface to be electromagnetically coupled), the convex portion is the coil. It will affect the appearance.

Next, a method for manufacturing the coil 10 will be described. FIG. 3 is a flowchart for explaining a method of manufacturing coil 10 according to the first embodiment of the present invention. The spiral conductor 2 formed in a flat plate shape is disposed at a predetermined position of the mold (step S31). FIG. 4 is a plan view of an upper mold and a lower mold for manufacturing the coil 10 according to Embodiment 1 of the present invention. FIG. 5 is a cross-sectional view of the upper die 45 and the lower die 41 shown in FIG. As shown in FIG. 4 (a), the lower mold 41 has a protrusion that is a positioning means that contacts the outside of the spiral conductor 2 so that the spiral conductor 2 does not deviate from a predetermined position. A (first protrusion) 42 is provided. In step S31 of FIG. 3, the spiral conductor 2 is disposed in the lower mold 41 so that the outer side of the spiral conductor 2 is in contact with the protrusion 42, thereby making the spiral conductor 2 a predetermined mold. It can be arranged at the position.

As shown in FIG. 4 (b), the upper mold 45 has a protrusion which is a pressing means for pressing a part of the spiral conductor 2 against the lower mold 41 when fitted to the lower mold 41. A (second protrusion) 46 is provided. As shown in FIG. 5, when the upper mold 45 and the lower mold 41 are fitted, the protrusion 42 prevents the spiral conductor 2 from being displaced, and the protrusion 46 extends from the lower mold 41. The spiral conductor 2 is prevented from floating. The protrusions (first protrusions) 42 are not provided in the lower mold 41, and the protrusions (second protrusions) 46 are not limited to the upper mold 45.

Referring back to FIG. 3, the mold is filled with a curable resin containing a magnetic material (step S32). As shown in FIG. 5, when the upper mold 45 and the lower mold 41 are fitted, a cavity 48 is formed between the upper mold 45 and the lower mold 41. The cavity 48 is filled with a curable resin containing a magnetic material heated to a softening temperature.

The curable resin filled in the mold is cured to mold the flat resin structure 3 (step S33). The portion where the spiral conductor 2 and the lower mold 41 are in contact (the portion where the spiral conductor 2 is present on the one surface 31 of the resin structure 3) is not filled with the curable resin. This portion of the conductor 2 is exposed to the outside. In addition, since the resin structure 3 is shape | molded using the metal mold | die, it is easy to provide the hole etc. for attaching to another member in the resin structure 3. FIG.

As described above, the coil 10 according to the first embodiment incorporates the spiral conductor 2 so as to be biased toward the one surface 31 side of the resin structure 3, and in particular, the one surface 31 of the resin structure 3. When a part of the spiral conductor 2 is exposed to the outside on the side, one surface (one surface 31 side) of the spiral conductor 2 exposed to the outside becomes a surface to be electromagnetically coupled, and the spiral conductor Since all the surfaces other than the electromagnetically coupled surface 2 are covered with the curable resin containing the magnetic material, the magnetic flux of the spiral conductor 2 generated on all the surfaces other than the one surface 31 is applied to the resin structure 3. Magnetic material that can be confined in the coil 10, can improve the inductance characteristics in the direction of the one surface 31 of the resin structure 3 in the coil 10, and obstructs magnetic flux on all surfaces other than the one surface 31. To increase the magnetic shield function Door can be.

In addition, since the coil 10 according to the first embodiment incorporates the spiral conductor 2 in the resin structure 3, the mechanical strength is improved and the deformation of the coil 10 due to the application of external force is suppressed. It is possible to prevent the characteristic of inductance in the direction of the one surface 31 of the resin structure 3 in the coil 10 from being lowered, and to reduce the loss of electromagnetic coupling.

Furthermore, since the coil 10 according to the first embodiment can be manufactured by the above-described method, an expensive magnetic sheet, a flexible substrate, or the like is unnecessary, and a step of attaching the magnetic sheet to the coil, a flexible substrate The manufacturing cost is reduced because the step of bending the substrate and the step of attaching the flexible substrate to the groove become unnecessary.

Note that the coil 10 according to the first embodiment can reduce eddy currents generated in the resin structure 3 if the curable resin forming the resin structure 3 is made of an insulating material. The loss of electromagnetic coupling can be reduced.

In addition, the coil 10 according to the first embodiment uses the injection molding in which a mold is filled with a curable resin, and integrally forms the resin structure 3 and the spiral conductor 2 to form the spiral conductor 2. The structure is not limited to the structure built in the resin structure 3, and the structure in which the spiral conductor 2 is embedded in the resin structure 3 formed separately and the spiral conductor 2 is embedded in the resin structure 3 later. Also good.

(Embodiment 2)
In the second embodiment, both ends of the wire drawn from the spiral conductor 2 in the coil 10 according to the first embodiment will be specifically described with reference to the drawings. FIG. 6 is a perspective view of the coil 10 according to Embodiment 2 of the present invention. The coil 10 shown in FIG. 6 has basically the same configuration as the coil 10 shown in FIG. 1 of the first embodiment, and therefore the same components are denoted by the same reference numerals and detailed description thereof is omitted.

The coil 10 shown in FIG. 6A is in contact with both ends 25 and 25 of the

wire rods

21 and 22 exposed to the outside on the side surface 33 of the resin structure 3, and is electrically connected to a circuit board or the like (not shown). ing. The side surface 33 of the resin structure 3 is a surface perpendicular to the one surface 31 of the resin structure 3. The coil 10 shown in FIG. 6B is exposed to the outside on the side surface 33 of the resin structure 3, and both ends 25 and 25 of the

wire materials

21 and 22 bent along the boundary line 34 between the one surface 31 and the side surface 33. And is electrically connected to a circuit board or the like. The coil 10 shown in FIG. 6C is exposed to the outside at the side surface 33 of the resin structure 3 and contacts the both ends 25 and 25 of the

wire materials

21 and 22 bent along the side surface 33 and the other surface 32. It is electrically connected to the substrate.

In order to electrically connect the coil 10 and the circuit board or the like, the both ends 25 and 25 of the

wire materials

21 and 22 exposed to the outside on any one surface of the resin structure 3 and the terminals provided on the circuit board or the like are directly connected. However, in order to more reliably connect the coil 10 and the circuit board or the like more securely, terminals that are electrically connected to both ends 25 and 25 of the

wire materials

21 and 22 may be provided. FIG. 7 is a perspective view of a structure in which a terminal is provided in the coil 10 according to the second embodiment of the present invention.

The coil 10 shown in FIG. 7A has one side 31 and side surface of the resin structure 3 that are electrically connected to both ends 25 and 25 of the

wire materials

21 and 22 exposed to the outside on the side surface 33 of the resin structure 3. 33, the terminal 7 having a shape in contact with the three surfaces of the other surface 32 is provided. The coil 10 shown in FIG. 7B is exposed to the outside on the side surface 33 of the resin structure 3, and both ends 25 and 25 of the

wire materials

21 and 22 bent along the boundary line 34 between the one surface 31 and the side surface 33. Terminal 7 having a shape in contact with three surfaces of one surface 31, side surface 33, and the other surface 32 of resin structure 3. The coil 10 shown in FIG. 7C is exposed to the outside on the side surface 33 of the resin structure 3 and is electrically connected to both ends 25 and 25 of the

wire rods

21 and 22 bent along the side surface 33 and the other surface 32. The terminal 7 has a shape in contact with the three surfaces of the one surface 31, the side surface 33, and the other surface 32 of the resin structure 3. The terminal 7 is bent along one surface 31, the side surface 33, and the other surface 32 of the resin structure 3, and has a U-shaped cross-sectional shape. Further, the contact area between the terminal 7 and both ends 25 and 25 of the

wire rods

21 and 22 increases in the order of FIG. 7A, FIG. 7B, and FIG. Etc. can be electrically connected.

It is also conceivable to use a conductive material when the ends 25 and 25 of the

wire rods

21 and 22 are electrically connected to the terminals. FIG. 8 is a perspective view of another structure in which a terminal is provided in the coil 10 according to Embodiment 2 of the present invention. The coil 10 shown in FIG. 8A has a plate-like terminal 8 in contact with the other surface 32, which is electrically connected to both ends 25, 25 of the

wire rods

21, 22 using a conductive material 81. The coil 10 shown in FIG. 8B has one surface 31, a side surface 33, and the other surface 32 of the resin structure 3 electrically connected to both ends 25 and 25 of the

wire materials

21 and 22 using a conductive material 81. Terminal 7 having a shape in contact with these three surfaces. The coil 10 shown in FIG. 8C has one surface 31 and a side surface 33 of the resin structure 3 electrically connected to both ends 25 and 25 of the

wire materials

21 and 22 on one surface 31 using the conductive material 81. The terminal 7 has a shape in contact with three surfaces of the other surface 32. Note that the conductive material 81 can be solder, silver paste, a conductive seal, or the like.

As shown in FIGS. 6 to 8, the coil 10 according to the second embodiment of the present invention connects both ends 25 and 25 of the

wire materials

21 and 22 drawn out from the spiral conductor 2 to any one of the resin structures 3. It is not limited to the structure exposed to the outside on one side, but both ends 25, 25 of the

wire rods

21, 22 drawn out from the spiral conductor 2 are exposed to the outside from the recesses or projections provided in the resin structure 3. It is good also as a structure. The recess or protrusion is provided on one surface of the resin structure 3. FIG. 9 is a perspective view of another structure of the coil 10 according to Embodiment 2 of the present invention. The coil 10 shown in FIG. 9A is exposed to the outside from a protrusion 91 provided on one surface 31 of the resin structure 3 and is bent at approximately both ends of the

wire rods

21 and 22 along the substantially central axis of the protrusion 91. 25 and 25 and is electrically connected to a circuit board or the like (not shown). The coil 10 shown in FIG. 9B is exposed to the outside from the protrusion 91 provided on the other surface 32 of the resin structure 3, and both ends 25 and 25 of the

wire rods

21 and 22 bent along the protrusion 91. It contacts and is electrically connected to a circuit board or the like. The protrusion 91 is a cylindrical structure formed of the same curable resin as that of the resin structure 3, and is provided on one surface 31 or the other surface 32 in the region of the resin structure 3 including the

wires

21 and 22. It has been.

FIG. 10 is a perspective view of still another structure of the coil according to Embodiment 2 of the present invention. A coil 10 shown in FIG. 10A is exposed to the outside from a recess 101 provided on one surface 31 or the other surface 32 of the resin structure 3 and is bent along a substantially central axis of the recess 101. 22 is in contact with both ends 25 and 25 and is electrically connected to a circuit board or the like (not shown). The recess 101 has a structure in which one surface 31 or the other surface 32 of the resin structure 3 is dug in a columnar shape, and one surface 31 or the other in the region of the resin structure 3 in which the

wires

21 and 22 are incorporated. The surface 32 is provided. The coil 10 shown in FIG. 10B is in contact with both ends 25 and 25 of the

wire rods

21 and 22 exposed to the outside from the concave portion 102 provided on one surface 31 or the other surface 32, and is electrically connected to a circuit board or the like. Connected. The recess 102 has a structure in which one surface 31 or the other surface 32 of the resin structure 3 is dug in a square column shape, and one surface 31 or the other in the region of the resin structure 3 in which the

wires

21 and 22 are embedded. The surface 32 is provided. The coil 10 shown in FIG. 10C is in contact with both ends 25 and 25 of the

wire rods

21 and 22 exposed to the outside from the

recesses

103 and 104 provided on the one surface 31 or the other surface 32, respectively, on the circuit board or the like. Electrically connected. The

concave portions

103 and 104 have a structure in which one surface 31 or the other surface 32 of the resin structure 3 is dug in a square column shape, and one surface in the region of the resin structure 3 in which the

wires

21 and 22 are incorporated. 31 or the other surface 32. Further, the

recesses

101, 102, 103, 104 provided on the one surface 31 or the other surface 32 may be open or closed on the other surface 32 side or the one surface 31 side.

In the coil 10 shown in FIG. 10C, terminals that are electrically connected to both ends 25 and 25 of the

wire materials

21 and 22 may be provided. FIG. 11 is a perspective view of a structure in which a terminal is provided on the coil 10 shown in FIG. In the coil 10 shown in FIG. 11A, plate-like terminals 11 are provided in the

recesses

103 and 104, respectively, and the plate-

like terminals

11 and 11 provided in the

recesses

103 and 104 are in contact with the

wire materials

21 and 22, respectively. By doing so, the

terminals

11 and 11 and both ends 25 and 25 of the

wire materials

21 and 22 are electrically connected. The coil 10 shown in FIG. 11B uses a conductive material 11a to electrically connect the plate-

like terminals

11 and 11 provided in the

recesses

103 and 104 and both ends 25 and 25 of the

wire materials

21 and 22, respectively. is doing.

The coil 10 shown in FIGS. 7 and 8 is provided on one surface of the resin structure 3 without incorporating the

terminals

7 and 8 in the resin structure 3, but is not particularly limited. The coil 10 according to the second embodiment may incorporate the

terminals

7 and 8 in the resin structure 3. FIG. 12 is a perspective view of a structure in which a terminal is built in the resin structure 3 of the coil 10 according to Embodiment 2 of the present invention. The coil 10 shown in FIG. 12 has a terminal 12 in the resin structure 3 that is electrically connected to both ends 25 and 25 of the

wires

21 and 22. The terminal 12 has a connection portion 12a exposed to the outside on one surface of the resin structure 3, and the coil 10 is connected by connecting the connection portion 12a to a terminal of a circuit board or the like (not shown). Are electrically connected to a circuit board and the like.

The coil 10 according to the second embodiment has the terminal 12 built in the resin structure 3, but is not limited to the structure shown in FIG. FIG. 13 is a perspective view of another structure in which a terminal is built in the resin structure 3 of the coil 10 according to Embodiment 2 of the present invention. A coil 10 shown in FIG. 13A has a terminal 13 having a connection portion 13a exposed to the outside from one surface 31 of the resin structure 3 incorporated in the resin structure 3. The coil 10 shown in FIG. 13B has a terminal 14 having a connection portion 14 a exposed to the outside on the side surface 33 of the resin structure 3 incorporated in the resin structure 3. The coil 10 shown in FIG. 13C has a terminal 15 having a connection portion 15 a in a portion protruding from the side surface 33 of the resin structure 3 in the resin structure 3. In addition, the coil 10 and a circuit board etc. are electrically connected by connecting the

connection parts

13a, 14a, and 15a to terminals, such as a circuit board.

FIG. 14 is a schematic diagram for explaining a method of manufacturing the coil 10 shown in FIG. In the step shown in FIG. 14A, both ends 25 and 25 of the

wire materials

21 and 22 drawn from the spiral conductor 2 are electrically connected to the terminal 13. The terminal 13 has a connecting portion 13 a on the surface opposite to the surface connected to both ends 25, 25 of the

wires

21, 22.

In the step shown in FIG. 14B, a spiral shape connected to the terminal 13 so that the outside of the spiral conductor 2 is in contact with the protrusion 42 for preventing the spiral conductor 2 from being displaced from a predetermined position. The conductor 2 is disposed in the lower mold 41. Since the lower mold 41 is provided with a protrusion 43 for supporting the terminal 13, the terminal 13 is placed at the position of the protrusion 43 when the spiral conductor 2 is disposed on the lower mold 41. Deploy. The upper mold 45 is fitted to the lower mold 41 so as to cover the spiral conductor 2. The upper mold 45 is provided with a protrusion 46 that presses a part of the spiral conductor 2 against the lower mold 41 when fitted to the lower mold 41, and the terminal 13 and the connection section 13a. Is formed.

In the step shown in FIG. 14 (c), the cavity 48 formed between the upper mold 45 and the lower mold 41 is filled with a curable resin containing a magnetic material heated to a softening temperature, The filled curable resin is cured, and the resin structure 3 incorporating the terminals 13 is molded.

As described above, the coil 10 according to the second embodiment includes the

ends

25 and 25 of the

wire materials

21 and 22 drawn from the spiral conductor 2 as described above or the

terminals

7, 8, 11, 12, 13 and 14. , 15 is connected to a circuit board or the like, so that the coil 10 and the circuit board or the like can be easily electrically connected.

In the coil 10 according to the second embodiment, the resin structure 3 and the spiral conductor 2 and the

terminals

12, 13, 14, and 15 are integrated using injection molding in which a mold is filled with a curable resin. The spiral conductor 2 and the

terminals

12, 13, 14, 15 are not limited to the configuration in which the resin structure 3 is built into the resin structure 3. 12, 13, 14, 15 may be embedded later, and the spiral conductor 2 and the

terminals

12, 13, 14, 15 may be built in the resin structure 3.

(Embodiment 3)
FIG. 15 is a perspective view of the coil 10 according to Embodiment 3 of the present invention. 16 is a cross-sectional view of the coil 10 shown in FIG. 15 taken along the line CC. The coil 10 shown in FIGS. 15 and 16 has basically the same configuration as that of the coil 10 shown in FIGS. 1 and 2 of the first embodiment. Detailed explanation is omitted.

As shown in FIG. 15, the coil 10 includes a spiral conductor 2 formed in a flat plate shape and a flat resin structure 3 formed of two layers having different contents of the magnetic material. .

The resin structure 3 is composed of two layers, a first layer 35 located on the lower side of the paper surface of FIG. 15 and a second layer 36 located on the upper side of the first layer 35. The first layer 35 and the second layer 36 are formed of a curable resin obtained by kneading a magnetic material such as ferrite into powder. By sandwiching the spiral conductor 2 between the first layer 35 and the second layer 36, the spiral conductor 2 is built in the resin structure 3. In the resin structure 3, the content of the magnetic material of the first layer 35 is set higher than the content of the magnetic material of the second layer 36. In particular, when the content of the magnetic material of the second layer 36 is set to 0 (zero) and the spiral conductor 2 is embedded in the first layer 35, one surface of the first layer 35 that is in contact with the second layer 36. 31 is a surface of the spiral conductor 2 to be electromagnetically coupled, and all surfaces other than the surface of the spiral conductor 2 to be electromagnetically coupled are covered with a magnetic material that prevents magnetic flux, whereby one surface 31 of the first layer 35 is covered. The magnetic flux of the spiral conductor 2 generated on all other surfaces can be confined in the first layer 35, and the inductance characteristics in the direction of the one surface 31 of the first layer 35 in the coil 10 can be enhanced. The magnetic shield function of all surfaces other than the one surface 31 of the one layer 35 can be enhanced.

As described above, in the coil 10 according to the third embodiment, even if the first layer 35 and the second layer 36 have the same thickness, the content of the magnetic material in the first layer 35 is set to the second level. When the spiral conductor 2 is embedded in the first layer 35 so as to be higher than the content of the magnetic material of the layer 36, all surfaces other than the electromagnetically coupled surface of the spiral conductor 2 are contained in the magnetic material. Can be covered with a curable resin having a higher rate, and the magnetic flux of the spiral conductor 2 generated on all surfaces other than the one surface 31 of the first layer 35 can be confined in the first layer 35. In addition, it is possible to improve the inductance characteristics in the direction of the one surface 31 of the first layer 35 and to enhance the magnetic shield function of all surfaces other than the one surface 31 of the first layer 35.

In addition, the coil 10 according to the third embodiment has a spiral conductor 2 sandwiched between the first layer 35 and the second layer 36, so that the mechanical strength is improved and an external force is applied. By suppressing the deformation of the coil 10, it is possible to prevent the inductance characteristic of the coil 10 from being lowered and to reduce the loss of electromagnetic coupling.

The coil 10 according to the third embodiment can reduce eddy currents generated in the resin structure 3 if the curable resin forming the resin structure 3 is made of an insulating material. The loss of electromagnetic coupling can be reduced.

The coil 10 according to the third embodiment is not limited to the case where the first layer 35 and the second layer 36 have the same thickness, and the second layer 36 is made thinner than the first layer 35. Also good.

(Embodiment 4)
FIG. 17 is a perspective view of a coil module according to Embodiment 4 of the present invention. 18 is a DD cross-sectional view of the coil module shown in FIG. As shown in FIG. 17, the coil module 1 includes a flat coil 10 having a spiral conductor 2 formed in a flat plate and a flat resin structure 3 containing a magnetic material, and the coil 10. And a circuit board 4 electrically connected to each other.

The resin structure 3 is made of a curable resin obtained by kneading a magnetic material such as ferrite into a flat plate shape. Further, the spiral conductor 2 is embedded in a biased manner toward one surface (surface to be electromagnetically coupled) 31 that is one surface of the resin structure 3. That is, the thickness from the spiral conductor 2 to one surface 31 of the resin structure 3 is made thinner than the thickness from the spiral conductor 2 to the other surface 32 that is one surface of the resin structure 3. .

In particular, in the coil module 1 according to the fourth embodiment, as shown in FIG. 18, the thickness of the resin structure 3 is reduced by reducing the thickness from the spiral conductor 2 to one surface 31 of the resin structure 3. A part of the spiral conductor 2 is exposed to the outside on the one surface 31 side. When a part of the spiral conductor 2 is exposed to the outside on the one surface 31 side, one surface (one surface 31 side) of the spiral conductor 2 exposed to the outside becomes a surface to be electromagnetically coupled, Since all surfaces other than the electromagnetically coupled surface of the spiral conductor 2 are covered with the curable resin containing the magnetic material, the magnetic flux of the spiral conductor 2 generated on all surfaces other than the one surface 31 is generated. It can be confined in the resin structure 3, and the characteristic of inductance in the direction of the one surface 31 of the resin structure 3 in the coil 10 is enhanced and the magnetic shield function of all surfaces other than the one surface 31 is enhanced. be able to.

Further, the portion where the wire 21 drawn out from the inside of the spiral conductor 2 and the flat plate portion of the spiral conductor 2 overlap is the convex portion 23. However, in the coil 10 according to the fourth embodiment, since the spiral conductor 2 is built in the resin structure 3 so that the convex portion 23 is embedded in the resin structure 3, the convex portion 23 is the appearance of the coil 10. Does not affect.

As shown in FIG. 17, the coil 10 includes both ends 25 of the

wire rods

21 and 22 exposed to the outside from the concave portions (first concave portions) 135 and 136 provided on the one surface 31 or the other surface 32 of the resin structure 3. 25 and is electrically connected to the circuit board 4. The

recesses

135 and 136 have a structure in which one surface 31 or the other surface 32 of the resin structure 3 is dug in a square column shape, and one surface in the region of the resin structure 3 in which the

wires

21 and 22 are incorporated. 31 or the other surface 32. 17 and 18, the circuit board 4 is disposed on the other surface 32 side of the resin structure 3, and therefore when the

concave portions

135 and 136 are provided on one surface 31, the other surface 32 is provided. The side needs to be an opening, but when the

recesses

135 and 136 are provided on the other surface 32, the one surface 31 side may be an opening or a closing.

The circuit board 4 is mounted with a predetermined circuit for processing an electric signal flowing through the coil 10. For example, in the coil module 1 used for the power receiving side device, the power reception including at least a rectifier circuit, a regulator circuit, and a charge control circuit. The side circuit 141 is mounted on the circuit board 4, and in the coil module 1 used for the power transmission side device, the power transmission side circuit 142 including at least a power control circuit and an inverter circuit is mounted on the circuit board 4. By mounting the power receiving circuit 141 or the power transmitting circuit 142 on the circuit board 4, the coil module 1 can be reduced in size.

Further, the circuit board 4 has protrusions (second protrusions) 145 and 146 provided with terminals that are electrically connected to both ends 25 and 25 of the

wire rods

21 and 22 drawn from the spiral conductor 2. . By fitting the

projections

145 and 146 into the

recesses

135 and 136 provided in the resin structure 3, the coil 10 and the circuit board 4 are electrically connected. In addition, the circuit board 4 can be fixed at a predetermined position with respect to the resin structure 3 by fitting the

recesses

135 and 136 and the

protrusions

145 and 146. The coil module 1 shown in FIG. 17 is a concave portion having a structure in which one surface 31 or the other surface 32 of the resin structure 3 is dug in a column shape in order to further strengthen the fixation between the circuit board 4 and the resin structure 3. 37 and 38 are provided on one surface 31 or the other surface 32, and

projections

147 and 148 are provided on the circuit board 4 so that the

recesses

37 and 38 and the

projections

147 and 148 are fitted.

Although the case where the power reception side circuit 141 or the power transmission side circuit 142 is mounted on the surface of the circuit board 4 facing the resin structure 3 is illustrated, the coil module 1 according to the fourth embodiment is particularly limited. Instead, the power reception side circuit 141 or the power transmission side circuit 142 may be mounted on a surface other than the surface facing the resin structure 3.

In addition, a configuration is shown in which the coil 10 and the circuit board 4 are electrically connected in contact with both ends 25 and 25 of the

wire rods

21 and 22 exposed to the outside from the

recesses

135 and 136 provided on the other surface 32. However, the coil module 1 according to the fourth embodiment is not particularly limited, and may have a configuration described below.

FIG. 19 is a perspective view showing another configuration of the coil 10 of the coil module 1 according to Embodiment 4 of the present invention. The coil 10 shown in FIG. 19 includes a wire 21 exposed to the outside after being bent along substantially the central axis of the recesses (first recesses) 301 and 302 provided on one surface 31 or the other surface 32 of the resin structure 3. 22 is in contact with both ends 25, 25 and is electrically connected to the circuit board 4. The

recesses

301 and 302 have a structure in which one surface 31 or the other surface 32 of the resin structure 3 is dug in a cylindrical shape, and one surface 31 in the region of the resin structure 3 in which the

wires

21 and 22 are incorporated. Alternatively, it is provided on the other surface 32. The coil 10 of the coil module 1 shown in FIG. 19 has basically the same configuration as the coil 10 of the coil module 1 shown in FIG. Omitted.

Both ends 25 and 25 of the

wire rods

21 and 22 are exposed to the outside along the substantially central axis of the

cylindrical recesses

301 and 302, but may be exposed along the side surfaces of the

recesses

301 and 302. A method of processing both ends 25 and 25 of the

wire materials

21 and 22 so as to be exposed along the side surfaces of the

recesses

301 and 302 will be described below. FIG. 20 is a schematic diagram for explaining a method of processing both ends 25, 25 of the

wire materials

21, 22 so as to be exposed along the side surfaces of the

recesses

301, 302. As shown in FIG. 20 (a), a predetermined temperature is applied from the one surface 31 side of the resin structure 3 to the

recesses

301 and 302 where both ends 25 and 25 of the

wire rods

21 and 22 are exposed by being bent along substantially the central axis. The heated pin 401 is inserted. As shown in FIG. 20B, when the pins 401 are inserted into the

recesses

301 and 302, both ends 25 and 25 of the

wires

21 and 22 are pressed against the side surfaces of the

recesses

301 and 302 by the heated pins 401. It is embedded in the curable resin on the side surfaces of the

softened recesses

301 and 302.

FIG. 21 is a schematic diagram for explaining another method of processing the both ends 25 and 25 of the

wire rods

21 and 22 so as to be exposed along the side surfaces of the

recesses

301 and 302. As shown in FIG. 21 (a), both ends 25 and 25 of the

wire rods

21 and 22 exposed by bending along the substantially central axis of the

recesses

301 and 302 are made of the resin structure 3 with a trowel 501 heated to a predetermined temperature. It is pressed against the other surface 32. As shown in FIG. 21 (b), when both ends 25, 25 of the

wires

21, 22 are pressed against the other surface 32 of the resin structure 3, both ends 25, 25 of the

wires

21, 22 become While being bent along the side surface and the other surface 32, it is embedded in the curable resin of the other surface 32 softened by the heated iron 501.

FIG. 22 is a perspective view showing still another configuration of the coil 10 of the coil module 1 according to Embodiment 4 of the present invention. The coil 10 shown in FIG. 22 is exposed to the outside from the

protrusions

61 and 62 provided on the one surface 31 or the other surface 32 of the resin structure 3, and is bent along the substantially central axis of the

protrusions

61 and 62. The

wires

21 and 22 are in contact with both ends 25 and 25 of the

wires

21 and 22 and are electrically connected to the circuit board 4. The

protrusions

61 and 62 are cylindrical structures formed of the same curable resin as the resin structure 3, and one surface 31 or the other surface 32 in the region of the resin structure 3 in which the

wires

21 and 22 are embedded. Is provided. Note that the coil 10 shown in FIG. 22 has basically the same configuration as the coil 10 of the coil module 1 shown in FIG. 17, and therefore, the same components are denoted by the same reference numerals and detailed description thereof is omitted.

In addition, the resin structure 3 has

protrusions

63 and 64 of a cylindrical structure formed of the same curable resin as the resin structure 3 on one surface 31 or the other surface 32 of the resin structure 3 as shown in FIG. The coil structure 1 is provided in place of the

concave portions

37 and 38 of the resin structure 3. Therefore, although not shown, the circuit board 4 is provided with a recess at each position corresponding to the

protrusions

61, 62, 63, 64 provided on the resin structure 3. The circuit board 4 can be fixed at a predetermined position with respect to the resin structure 3 by fitting the

protrusions

61, 62, 63, 64 into the respective concave portions provided at the corresponding positions. The recesses (second recesses) provided at the respective positions of the circuit board 4 corresponding to the protrusions (first protrusions) 61 and 62 have terminals that are electrically connected to the coil 10. Both ends 25 and 25 of the

wire rods

21 and 22 exposed to the outside from the

protrusions

61 and 62 are in contact with the terminals, and the coil 10 and the circuit board 4 are electrically connected.

As described above, in the coil module 1 according to the fourth embodiment, the circuit board 4 is built in the spiral conductor 2 in a biased manner outside the predetermined interference region where the circuit board 4 interferes with the magnetic flux of the spiral conductor 2. Since the circuit board 4 does not disturb the magnetic flux of the spiral conductor 2 and is disposed on one surface (one surface 31) opposite to the one surface (one surface 31) of the resin structure 3, the electromagnetic coupling Loss can be reduced. The circuit board 4 is not limited to a case where the circuit board 4 is disposed outside a predetermined interference region that interferes with the magnetic flux of the spiral conductor 2, and at least a component that interferes with the magnetic flux of the spiral conductor 2. May be arranged outside the predetermined interference area, if it is arranged outside the predetermined interference area.

In addition, the coil 10 of the coil module 1 according to the fourth embodiment has the spiral conductor 2 embedded in the resin structure 3 so as to be biased toward the one surface (one surface 31) side, particularly the one surface 31 side. 1 is exposed to the outside, one surface (one surface 31 side) of the spiral conductor 2 exposed to the outside becomes a surface to be electromagnetically coupled, and other than the electromagnetically coupled surface of the spiral conductor 2 Are covered with a curable resin containing a magnetic material, so that the magnetic flux of the spiral conductor 2 generated on all surfaces other than the one surface 31 can be confined in the resin structure 3, Inductive properties in the direction of the one surface 31 of the resin structure 3 in the coil 10 can be enhanced, and all surfaces other than the one surface 31 of the resin structure 3 have a large amount of magnetic material that blocks magnetic flux. Since it becomes, it has a coil 10 It is possible to increase the magnetic shielding function of yl module 1. In the coil 10 of the coil module 1 according to the fourth embodiment, since the spiral conductor 2 is built in the resin structure 3, the mechanical strength is improved and the coil 10 is deformed by an external force. By suppressing the above, it is possible to prevent the inductance characteristics of the coil 10 of the coil module 1 from being lowered, and to reduce the loss of electromagnetic coupling.

Furthermore, the coil module 1 according to the fourth embodiment is configured such that the protrusions (second protrusions) 145 and 146 are fitted into the recesses (first recesses) 135 and 136 provided in the resin structure 3. Since both ends 25 and 25 of the

wire materials

21 and 22 are in contact with the

projections

145 and 146 to electrically connect the coil 10 and the circuit board 4, work such as soldering is not required and the manufacturing cost is low. Become. Further, the position of the circuit board 4 with respect to the resin structure 3 can be fixed.

In the coil module 1 according to the fourth embodiment, both ends 25 and 25 of the

wire rods

21 and 22 are provided on the one surface (one surface 31 or the other surface 32) of the resin structure 3 (first surface 31 or other surface 32). 1 recess) 135, 136, 301, 302 and protrusions (first protrusions) 61, 62 are not limited to the configuration exposed to the outside, but both ends 25, 25 of the

wires

21, 22 are connected to the resin structure 3. Any one of these may be exposed to the outside. In the configuration in which both ends 25, 25 of the

wire rods

21, 22 are exposed to the outside on any one surface of the resin structure 3, both ends 25, 25 of the

wire rods

21, 22 exposed to the outside and terminals provided on the circuit board 4 are provided. In contact with each other, the coil 10 and the circuit board 4 are electrically connected.

Moreover, if the curable resin which forms the resin structure 3 is an insulating material, the coil module 1 which concerns on this Embodiment 4 can reduce the eddy current which arises in the resin structure 3, and electromagnetic coupling Loss can be reduced.

(Embodiment 5)
FIG. 23 is a plan view of coil module 1 according to Embodiment 5 of the present invention. 24 is a cross-sectional view of the coil module 1 shown in FIG. 23 taken along the line EE. As shown in FIG. 23, the coil module 1 according to Embodiment 5 also has a flat plate shape having a spiral conductor 2 formed in a flat plate shape and a flat resin structure 3 containing a magnetic material. Coil 10 and a circuit board 4 electrically connected to the coil 10. In addition, in the coil module 1 shown in FIG.23 and FIG.24, the same code | symbol is attached | subjected about the same component as the coil module 1 shown in FIG. 17 of Embodiment 4, and detailed description is abbreviate | omitted.

The circuit board 4 is arranged on the other surface 32 of the resin structure 3 so as to be separated from the inside of the spiral conductor 2 in the direction from the inside to the outside. That is, the circuit board 4 is arranged outside a predetermined region (interference region) 71 that interferes with the magnetic flux of the spiral conductor 2 on the other surface 32 of the resin structure 3. The circuit board 4 is built in the resin structure 3 so that the surface on which the circuit is mounted and the other surface 32 of the resin structure 3 are flush with each other. The coil 10 and the circuit board 4 are electrically connected by connecting the both ends 25 and 25 of the

wire materials

21 and 22 and the circuit board 4 built in the resin structure 3 by soldering or the like. In the case of the coil module 1 used for the power receiving device, the circuit board 4 is mounted with the power receiving circuit 141 including at least a rectifier circuit, a regulator circuit, and a charge control circuit. A power transmission side circuit 142 including at least a power control circuit and an inverter circuit is mounted. Furthermore, a connector 49 for connecting to another circuit board is mounted on the circuit board 4.

FIG. 25 is a side view of a circuit module using the coil module 1 according to Embodiment 5 of the present invention. As shown in FIG. 25A, the circuit module 90 is laminated in the order of the coil module 1, the battery pack 910, and the circuit board 92. That is, the circuit module 90 has a structure in which the battery pack 910 is sandwiched between the coil module 1 and the circuit board 92. By fitting the connector 49 mounted on the circuit board 4 and the connector 93 mounted on the circuit board 92, the coil module 1 and the circuit board 92 are electrically connected. The thickness when the connector 49 and the connector 93 are fitted secures the thickness of the battery pack 910. However, the thickness is not particularly limited to this, and the coil module 1 is provided with a protrusion, and the protrusion The thickness of the battery pack 910 may be secured by the height of the protruding portion by incorporating the circuit board 4 on which the connector 49 is mounted in the portion.

Further, since the battery pack 910 and the circuit board 92 are stacked on the other surface 32 of the resin structure 3 of the coil module 1, a spiral shape that is biased and built in the one surface 31 side of the resin structure 3. The magnetic flux of the conductor 2 is not disturbed. The coil 10 of the coil module 1 includes the spiral conductor 2 that is biased toward the one surface 31 side of the resin structure 3, and the resin structure 3 is formed of a curable resin containing a magnetic material. The magnetic shield function on the other surface 32 side of the resin structure 3 in which the battery pack 910 and the circuit board 92 are laminated is high, and the influence of the magnetic flux of the spiral conductor 2 on the battery pack 910 and the circuit board 92 can be reduced. it can.

Further, as shown in FIG. 25 (b), the circuit module 90 connects the coil module 1 and the circuit board 92 with the connector 49 and the connector 93, so that the coil module 1 and the circuit board 92 can be easily connected. Can be separated, and the battery pack 910 can be easily replaced. Although not shown, when the battery pack 910 and the circuit board 92 are electrically connected and the coil module 1 is a coil module used for a power receiving side device, the circuit module 90 receives the coil 10. The processed power can be rectified by the circuit board 4 and supplied to the battery pack 910 via the circuit board 92 to charge the battery pack 910.

FIG. 26 is a side view showing another configuration of the circuit module using the coil module 1 according to Embodiment 5 of the present invention. A circuit module 100 shown in FIG. 26 is laminated in the order of an outer case 111, a coil 10 having a spiral conductor 2 and a resin structure 3, a battery pack 910, and a circuit board 4. That is, the circuit module 100 has a structure in which the battery pack 910 is sandwiched between the coil 10 constituting the coil module 1 and the circuit board 4. The exterior case 111 is a component that forms the exterior of a device on which the circuit module 100 is mounted. For example, when the device on which the circuit module 100 is mounted is a mobile phone, it corresponds to a battery lid.

The coil 10 is electrically connected to the circuit board 4 via the wiring 112 provided in the exterior case 111. The resin structure 3 has a protruding portion 303 on one surface 31 in which the spiral conductor 2 is embedded in an eccentric manner, and both ends 25 and 25 of the

wires

21 and 22 are exposed from the protruding portion 303. On the other hand, the outer case 111 has a recess 113 at a position corresponding to the protrusion 303, and a wiring 112 is provided on one surface of the recess 113. By fitting the protrusion 303 of the resin structure 3 and the recess 113 of the outer case 111 filled with the conductive adhesive 114, both ends 25 and 25 of the

wires

21 and 22 and the wiring are connected via the conductive adhesive 114. 112 is electrically connected. In order to more firmly fix the resin structure 3 and the outer case 111, the resin structure 3 is provided with a protrusion 304, the outer case 111 is provided with a recess 115, and the recess 115 is filled with a conductive adhesive 114. The protrusion 304 and the recess 115 are fitted.

The coil 10 and the circuit board 4 are electrically connected by connecting the terminal 410 mounted on the circuit board 4 and the wiring 112. Although not shown, when the battery pack 910 and the circuit board 4 are electrically connected and the coil module 1 is a coil module used for a power receiving side device, the circuit module 100 receives power received by the coil 10. Can be supplied to the battery pack 910 to charge the battery pack 910.

In the circuit module 100, since the coil 10 and the outer case 111 are integrated, the battery pack 910 can be easily replaced simply by separating the outer case 111 from the circuit board 4. In addition, since the circuit module 100 covers the one surface 31 side of the resin structure 3 in which a part of the spiral conductor 2 is exposed to the outside with the exterior case 111, when the battery pack 910 is replaced. The spiral conductor 2 is not damaged.

As described above, in the coil module 1 according to the fifth embodiment, the circuit board 4 is outside the predetermined interference region where the circuit board 4 interferes with the magnetic flux of the spiral conductor 2, particularly from the inner side to the outer side of the spiral conductor 2. Since the circuit board 4 does not disturb the magnetic flux of the spiral conductor 2, the loss of electromagnetic coupling can be reduced.

Further, in the coil module 1 according to the fifth embodiment, since the circuit board 4 is built in the resin structure 3 as shown in FIG. 23, the work of attaching the circuit board 4 to the resin structure 3 is unnecessary. Manufacturing cost is reduced. The circuit board 4 may be incorporated in the resin structure 3 by injection molding or may be incorporated later in the molded resin structure 3. Further, by using the coil module 1 shown in FIG. 23, the circuit module 90 shown in FIG. 25 can be easily configured. The coil module 1 used for the circuit module is not limited to the configuration in which the circuit board 4 is built in the resin structure 3, but the circuit board 4 is built in the resin structure 3 as in the circuit module 100 shown in FIG. Instead, the battery pack 910 may be sandwiched between the coil 10 constituting the coil module 1 and the circuit board 4.

In the coil module 1 according to the fifth embodiment, the circuit board 4 is arranged on the other surface 32 of the resin structure 3 so as to be separated from the inside of the spiral conductor 2 toward the outside. However, the circuit board 4 may be disposed on one surface 31 of the resin structure 3 so as to be separated from the inside of the spiral conductor 2 in the direction from the inside to the outside.

(Embodiment 6)
FIG. 27 is a perspective view of the coil module 1 according to Embodiment 6 of the present invention. FIG. 28 is a sectional view taken along line FF of the coil module 1 shown in FIG. The coil module 1 shown in FIGS. 27 and 28 has basically the same configuration as that of the coil module 1 shown in FIGS. 17 and 18 of the fourth embodiment. Detailed description will be omitted.

As shown in FIG. 27, the coil module 1 is a flat plate having a spiral conductor 2 formed in a flat plate shape and a flat resin structure 3 formed of two layers having different contents of the magnetic material. And a circuit board 4 electrically connected to the coil 10.

The resin structure 3 is composed of two layers, a first layer 310 located above the circuit board 4 and a second layer 320 located above the first layer 310. The first layer 310 and the second layer 320 are formed of a curable resin obtained by kneading a magnetic material such as ferrite into powder. By sandwiching the spiral conductor 2 between the first layer 310 and the second layer 320, the spiral conductor 2 is built in the resin structure 3. In the resin structure 3, the content of the magnetic material of the first layer 310 is higher than the content of the magnetic material of the second layer 320. In particular, when the content rate of the magnetic material of the second layer 320 is set to 0 (zero) and the spiral conductor 2 is embedded in the first layer 310, one surface of the first layer 310 in contact with the second layer 320 is provided. 31 is a surface on which the spiral conductor 2 is electromagnetically coupled, and all surfaces other than the electromagnetically coupled surface of the spiral conductor 2 are covered with a magnetic material that prevents magnetic flux, whereby one surface 31 of the first layer 310 is covered. The magnetic flux of the spiral conductor 2 generated on all other surfaces can be confined in the first layer 310, and the inductance characteristics in the direction of the one surface 31 of the first layer 310 in the coil 10 can be enhanced. The magnetic shield function of all surfaces other than the one surface 31 of the one layer 310 can be enhanced.

As described above, in the coil 10 of the coil module 1 according to the sixth embodiment, even if the first layer 310 and the second layer 320 have the same thickness, the content of the magnetic material in the first layer 310 Is made higher than the content of the magnetic material of the second layer 320, and the spiral conductor 2 is embedded in the first layer 310, all the surfaces other than the electromagnetically coupled surface of the spiral conductor 2 are magnetized. It can be covered with a curable resin having a higher content of body material, and the magnetic flux of the spiral conductor 2 generated on all surfaces other than the one surface 31 of the first layer 310 can be confined in the first layer 310. In addition, the characteristic of the inductance in the direction of the one surface 31 of the first layer 310 in the coil 10 is enhanced, and all the surfaces other than the one surface 31 of the first layer 310 contain more magnetic material that blocks magnetic flux. So a coil module comprising a coil 10 It is possible to increase the magnetic shielding function.

In addition, since the coil 10 of the coil module 1 according to the sixth embodiment has the spiral conductor 2 built in the resin structure 3 composed of two layers, the mechanical strength is improved and an external force is applied. By suppressing the deformation of the coil 10, it is possible to prevent the inductance characteristic of the coil 10 of the coil module 1 from being lowered and to reduce the loss of electromagnetic coupling.

In addition, the coil 10 of the coil module 1 according to Embodiment 6 is not limited to the case where the first layer 310 and the second layer 320 have the same thickness, and the second layer 320 is replaced with the first layer 310. It may be thinner.

DESCRIPTION OF SYMBOLS 1 Coil module 2 Conductor 3

Resin structure

4, 92

Circuit board

7, 8, 11, 12, 13, 14, 15 Terminal 10

Coil

21, 22 Wire 25 Both ends 37, 38, 101, 102, 103, 104, 113, 115, 135, 136, 301, 302 Recess 41

Upper mold

42, 43, 46, 91 Protrusion 45

Lower mold

47, 48

Cavity

49, 93

Connector

61, 62, 63, 64, 145, 146, 147, 148, 303, 304

Protrusion

90, 100 Circuit module 111 Exterior case 112 Wiring 141 Power reception side circuit 142 Power transmission side circuit 401 Pin 410 Terminal 501 Iron 910 Battery pack

Claims

A spiral conductor formed in a flat plate shape;
A flat resin structure containing a magnetic material,
A coil characterized in that the conductor is embedded in a biased manner on one surface side of the resin structure.
The coil according to claim 1, wherein a part of the conductor is exposed to the outside on the one surface side of the resin structure.
The coil according to claim 1 or 2, wherein both ends of the wire drawn from the conductor are exposed to the outside on any one surface of the resin structure.
3. The coil according to claim 1, wherein both ends of the wire drawn from the conductor are exposed to the outside from a recess or protrusion provided on one surface of the resin structure.
The coil according to any one of claims 1 to 4, wherein a terminal that is electrically connected to both ends of the wire drawn from the conductor is provided on one surface of the resin structure.
A spiral conductor formed in a flat plate shape;
A flat resin structure containing a magnetic material,
The resin structure is composed of a first layer and a second layer having different contents of the magnetic material,
A coil, wherein the conductor is sandwiched between the first layer and the second layer.
Arranging a spiral conductor formed in a flat plate at a predetermined position of the mold; and
Filling the mold with a curable resin containing a magnetic material heated to a softening temperature;
Curing the curable resin filled in the mold, and forming a flat resin structure having the conductor biased to one side and containing the conductor.
The coil manufacturing method according to claim 7, further comprising positioning means for arranging the conductor at a predetermined position of the mold.
The coil manufacturing method according to claim 7 or 8, further comprising pressing means for pressing the conductor against the mold.
It is composed of a first mold and a second mold to be fitted,
At least one of the first mold and the second mold has a first protrusion as the positioning means,
At least one of the first mold and the second mold has a second protrusion as the pressing means,
The conductor is arranged at a predetermined position of the first mold or the second mold based on the first protrusion,
The method for manufacturing a coil according to claim 9, wherein a part of the conductor is pressed against the first mold or the second mold based on the second protrusion.
A coil according to any one of claims 1 to 6;
A coil module comprising: a circuit board mounted with a predetermined circuit that is electrically connected to the coil and processes an electrical signal flowing through the coil.
12. The coil module according to claim 11, wherein the circuit board is arranged outside a predetermined interference region that interferes with the magnetic flux of the conductor.
The coil module according to claim 11 or 12, wherein the circuit board is disposed on a surface opposite to one surface of the resin structure in which the conductor is embedded in a biased manner.
The coil module according to any one of claims 11 to 13, wherein the circuit boards are spaced apart in a direction from the inside to the outside of the conductor.
The circuit board is in contact with both ends of a wire drawn from the conductor exposed to the outside on any one surface of the resin structure, and is electrically connected to the coil. The coil module according to any one of claims 11 to 14.
The resin structure has a first protrusion or a first recess that exposes both ends of the wire drawn from the conductor on any one surface,
The circuit board has a second recess or a second protrusion provided with a terminal electrically connected to both ends of the wire drawn from the conductor,
The coil and the circuit board are electrically connected by fitting the first protrusion and the second recess, or the first recess and the second protrusion. The coil module according to any one of claims 11 to 14.
The coil module according to any one of claims 11 to 14, wherein the circuit board is built in the resin structure.
The coil module according to any one of claims 11 to 17, wherein a power reception side circuit including at least a rectifier circuit, a regulator circuit, and a charge control circuit is mounted on the circuit board.
The coil module according to any one of claims 11 to 17, wherein a power transmission circuit including at least a power control circuit and an inverter circuit is mounted on the circuit board.
The coil module according to any one of claims 11 to 19, wherein the resin structure is made of an insulating material.