WO2018008615A1

WO2018008615A1 - Electronic device

Info

Publication number: WO2018008615A1
Application number: PCT/JP2017/024415
Authority: WO
Inventors: 邦明用水; 一史愛須
Original assignee: 株式会社村田製作所
Priority date: 2016-07-06
Filing date: 2017-07-04
Publication date: 2018-01-11
Also published as: CN209249234U

Abstract

An electronic device (301) comprises: a first circuit (a circuit substrate (71)); a second circuit (a circuit formed on a mounting substrate (201)); an inductor bridge (101) connecting the first circuit and the second circuit; and a metal member (conductor (81)). The inductor bridge (101) is provided with an insulating base material (10) and a conical coil (3) formed on the insulating base material (10). The conical coil (3) is configured by including a plurality of loop conductors (small diameter loop conductors (31) and large diameter loop conductors (32)) arranged along the winding axis direction (the Z-axis direction). Changes along the Z-axis direction in the inner and outer diameters of the plurality of loop conductors occur in a single direction. The small diameter loop conductors (31), which have the smallest inner and outer diameters among the plurality of loop conductors, are arranged closer to the metal member than the other loop conductors (the large diameter loop conductors (32)).

Description

Electronics

The present invention relates to an electronic device, and particularly to an electronic device including an inductor bridge having an inductance component.

2. Description of the Related Art Conventionally, in a small electronic device such as a portable terminal, when mounting circuit members such as a plurality of boards are provided in a housing, for example, as shown in Patent Document 1, a mounting circuit member is formed with a flexible flat cable. Are connected.

FIG. 11 is an exploded perspective view of one inductor bridge 100 shown in Patent Document 1. FIG. The inductor bridge 100 includes a flexible insulating base (a laminate of

base layers

11a, 12a, 13a, and 14a) and a helical coil (

loop conductors

31a, 32a, and 33a) formed on the insulating base. , 34a, a helical coil).

International Publication No. 2014/129279

However, in the state where the inductor bridge as shown in Patent Document 1 is provided in the electronic device, an unnecessary stray capacitance may be generated between the metal body in the casing of the electronic device.

Also, when the flexible inductor bridge is provided in a limited space inside the electronic device, it may be provided in a state where a predetermined portion is bent. However, when the inductor bridge is bent, the interlayer capacitance of the helical coil may change with deformation of the insulating base material, and the electrical characteristics of the helical coil may change before and after bending.

An object of the present invention is to provide an electronic device including an inductor bridge in which stray capacitance generated between other metal bodies is reduced and fluctuation of electrical characteristics due to deformation is suppressed.

(1) The electronic device of the present invention
An inductor bridge, a first circuit, a second circuit, and a metal body;
The first circuit and the second circuit are connected via the inductor bridge;
The inductor bridge is
An insulating base material having a first main surface and having flexibility;
A conical coil formed on the insulating substrate and having a winding axis perpendicular to the first main surface;
Have
The conical coil is configured to include a plurality of loop-shaped conductors arranged along the winding axis direction of the conical coil,
The change along the winding axis direction of the inner and outer diameters of the plurality of loop-shaped conductors is one direction,
The plurality of loop-shaped conductors do not overlap each other when viewed from the winding axis direction,
The small-diameter loop conductor having the smallest inner and outer diameters among the plurality of loop conductors is arranged closer to the metal body than the other loop conductors.

The small-diameter loop-shaped conductor has the smallest inner and outer diameters among the plurality of loop-shaped conductors and the line length is short, and therefore has a smaller conductor area than other loop-shaped conductors. Therefore, with this configuration, the stray capacitance generated between the conical coil and the metal body is smaller than in the case where another loop conductor having a relatively large conductor area is disposed close to the other metal body. Get smaller.

Further, in this configuration, the other loop-shaped conductor having a relatively large conductor area is disposed at a position farther from the other metal body than the small-diameter loop-shaped conductor, so even if the inductor bridge is bent, the conical coil The amount of change in stray capacitance between the metal body and other metal bodies is small. Further, in this configuration, since the large-diameter loop conductor and the small-diameter loop conductor do not face each other, the interlayer capacitance between the large-diameter loop conductor and the small-diameter loop conductor is small.

(2) In the above (1), the insulating base material is preferably a laminate formed by laminating a plurality of base material layers made of a thermoplastic resin. In this configuration, since the insulating base material is a thermoplastic resin, the shape can be easily plastically processed according to the mounting state (unevenness or the like of the mounting destination).

(3) In the above (1) or (2), it is preferable that the inductor bridge includes a bent portion in part.

(4) In any one of the above (1) to (3), the conical coil is wound more than two turns, and when viewed from the winding axis direction, a portion of the conical coil that is wound most inside is provided. The first coil portion is defined, and the portion positioned n−1 (n is an integer of 2 or more) toward the outer peripheral side with respect to the first coil portion is defined as the nth coil portion, and the first coil portion is defined. The line width of the part is preferably narrower than the line widths of the other coil parts. By reducing the line width of the first coil portion, the conductor area of the first coil portion closest to the metal body can be reduced. Therefore, with this configuration, the facing area between the first coil portion and the metal body can be reduced, and the stray capacitance generated between the conical coil and the metal body can be further suppressed.

(5) In the above (4), it is preferable that the line width of the n-th coil part is narrower than the line width of the n + 1-th coil part. The nth coil portion is closer to the metal body than the (n + 1) th coil portion. Therefore, with this configuration, stray capacitance generated between the conical coil and the metal body can be effectively reduced as compared with the case where the line width of the (n + 1) th coil part is narrower than the line width of the nth coil part.

With this configuration, it is possible to realize an electronic device including an inductor bridge that reduces the stray capacitance generated between other metal bodies in a state of being provided in the electronic device and suppresses variation in electrical characteristics due to deformation.

According to the present invention, it is possible to realize an inductor bridge in which a stray capacitance generated between other metal bodies is reduced and a change in electrical characteristics due to deformation is suppressed, and an electronic apparatus including the inductor bridge.

FIG. 1A is a perspective view of the inductor bridge 101 according to the first embodiment, and FIG. 1B is an exploded perspective view of the inductor bridge 101. FIG. 2A is a plan view showing a portion where the conical coil 3 is formed in the inductor bridge 101, and FIG. 2B is a cross-sectional view of that portion. FIG. 3 is a cross-sectional view illustrating a main part of the electronic apparatus 301 according to the first embodiment. FIG. 4 is a cross-sectional view sequentially showing the manufacturing process of the inductor bridge 101A. FIG. 5A is a partial cross-sectional view showing the relationship between the inductor bridge 101 and the metal body 2 before bending, and FIG. 5B shows the relationship between the inductor bridge 101 and the metal body 2 in a bent state. It is a fragmentary sectional view shown. 6A is a partial cross-sectional view of another inductor bridge 101A according to the first embodiment, and FIG. 6B is a partial cross-sectional view of an inductor bridge 101B of a comparative example. FIG. 7 is a cross-sectional view showing a main part of an electronic device 302 according to the second embodiment. FIG. 8 is a cross-sectional view illustrating a main part of an electronic device 303 according to the third embodiment. FIG. 9A is a plan view showing a portion where the conical coil 3C is formed in the inductor bridge 104 according to the fourth embodiment, and FIG. 9B is a cross-sectional view of that portion. FIG. 10A is a plan view showing a portion where the conical coil 3D is formed in the inductor bridge 105 according to the fifth embodiment, and FIG. 10B is a cross-sectional view of that portion. FIG. 11 is an exploded perspective view of one inductor bridge disclosed in Patent Document 1. In FIG.

Hereinafter, several specific examples will be given with reference to the drawings to show a plurality of modes for carrying out the present invention. In each figure, the same reference numerals are assigned to the same portions. In consideration of ease of explanation or understanding of the main points, the embodiments are shown separately for convenience, but the components shown in different embodiments can be partially replaced or combined. In the second and subsequent embodiments, description of matters common to the first embodiment is omitted, and only different points will be described. In particular, the same operation effect by the same configuration will not be sequentially described for each embodiment.

<< First Embodiment >>
FIG. 1A is a perspective view of the inductor bridge 101 according to the first embodiment, and FIG. 1B is an exploded perspective view of the inductor bridge 101. FIG. 2A is a plan view showing a portion where the conical coil 3 is formed in the inductor bridge 101, and FIG. 2B is a cross-sectional view of that portion. In FIG. 2A, in order to make the structure easy to understand, the protective layer 1 and the base material layer 14 are not shown, and the opening BR surrounded by the large-diameter loop conductor 32 is shown by a dot pattern.

The inductor bridge 101 includes an insulating base 10, a conical coil 3 (described in detail later) formed on the insulating base 10, and

connectors

51 and 52.

The insulating substrate 10 is a rectangular parallelepiped thermoplastic resin flat plate having a first main surface VS1 and a second main surface VS2 facing the first main surface VS1, and having a longitudinal direction coinciding with the X-axis direction.

The “first main surface” in the present embodiment is arranged so as to face a member (for example, a mounting substrate or a housing) having a metal body (described in detail later) in a state where the inductor bridge is provided in the electronic device. It is the surface to be done. The “metal body” in the present embodiment is a metal member that is closest to the conical coil (inductor portion) provided in the inductor bridge in a state where the inductor bridge is provided in the electronic device, for example, a conductor pattern provided on the mounting substrate. And shield cases, metal housings, and the like.

The insulating base material 10 is a laminate formed by laminating the base material layers 11, 12, 13, 14 and the protective layer 1, and has flexibility. The plurality of base material layers 11, 12, 13, and 14 are sheet-like flat plates made of a thermoplastic resin whose main material is a liquid crystal polymer, for example, whose planar shape is rectangular, the longitudinal direction of which coincides with the X-axis direction. .

The electrode 41 is formed on the back surface of the base material layer 11. The electrode 41 is a conductor pattern having a rectangular planar shape disposed near the first end of the base material layer 11 (the right end of the base material layer 11 in FIG. 1B). The electrode 41 is a conductor pattern such as a Cu foil.

A small-diameter loop conductor 31 and a conductor 21 are formed on the back surface of the base material layer 12. The small-diameter loop-shaped conductor 31 is a rectangular loop-shaped conductor pattern of about 0.5 turns formed near the center of the base material layer 12. The conductor 21 is a linear conductor pattern extending in the X-axis direction, and is disposed at a position near the first end of the base material layer 12 from the vicinity of the center of the base material layer 12. The small-diameter loop conductor 31 and the conductor 21 are continuously formed, and the first end of the small-diameter loop conductor 31 is connected to the first end of the conductor 21. A second end of the conductor 21 is connected to the electrode 41 via an interlayer connection conductor V 1 formed on the base material layer 11. The small-diameter loop conductor 31 and the conductor 21 are conductor patterns such as Cu foil, and the interlayer connection conductor V1 is a via conductor or a through hole, for example.

In the present invention, the “small-diameter loop conductor” refers to a loop-shaped conductor having the smallest inner / outer diameter (inner diameter and outer diameter) among a plurality of loop conductors constituting the conical coil.

A large-diameter loop conductor 32 and a conductor 22 are formed on the surface of the base material layer 13. The large-diameter loop conductor 32 is a rectangular loop-shaped conductor pattern of about 1 turn formed near the center of the base material layer 13. As shown in FIG. 2A, the small-diameter loop conductor 31 has a smaller inner and outer diameter than the large-diameter loop conductor 32. The conductor 22 is a linear conductor pattern extending in the X-axis direction, and is closer to the second end of the base material layer 13 (the left end of the base material layer 13 in FIG. 1B) from near the center of the base material layer 13. Placed in position. The first end of the large-diameter loop conductor 32 is connected to the small-diameter loop conductor 31 via an interlayer connection conductor V2 formed on the base material layers 12 and 13. The large-diameter loop conductor 32 and the conductor 22 are continuously formed, and the second end of the large-diameter loop conductor 32 is connected to the first end of the conductor 22. The large-diameter loop conductor 32 and the conductor 22 are conductor patterns such as Cu foil, and the interlayer connection conductor V2 is a via conductor or a through hole, for example.

The electrode 42 is formed on the surface of the base material layer 14. The electrode 42 is a conductor pattern having a rectangular planar shape disposed near the second end of the base material layer 14 (the left end of the base material layer 14 in FIG. 1B). The electrode 42 is connected to the second end of the conductor 22 via an interlayer connection conductor V3 formed on the base material layer 14. The electrode 42 is a conductor pattern such as a Cu foil, and the interlayer connection conductor V3 is a via conductor or a through hole, for example.

The protective layer 1 has substantially the same planar shape as the base material layer 14 and is laminated on the surface of the base material layer 14. The protective layer 1 has an opening AP1 corresponding to the position of the electrode 42. Therefore, the electrode 42 is exposed to the second main surface VS2 of the insulating base material 10. The protective layer 1 is, for example, a solder resist film. The protective layer 1 is not essential.

The connector 51 is provided on the first main surface VS1 of the insulating base material 10, and is disposed at the first end in the longitudinal direction of the insulating base material 10 (the right end of the insulating base material 10 in FIG. 1A). The connector 51 is connected to the electrode 41. The connector 52 is provided on the second main surface VS 2 of the insulating base 10 and is disposed at the second end in the longitudinal direction of the insulating base 10 (the left end of the insulating base 10). The connector 52 is connected to the electrode 42.

In the inductor bridge 101, the rectangular conical coil 3 of about 1.5 turns is configured including the small-diameter loop conductor 31, the large-diameter loop conductor 32, and the interlayer connection conductor V2. As shown in FIG. 2B, the conical coil 3 has a winding axis AX orthogonal to the first main surface VS1 and the second main surface VS2 (parallel to the Z-axis direction).

As shown in FIG. 2B, the plurality of loop-shaped conductors (small-diameter loop-shaped conductor 31 and large-diameter loop-shaped conductor 32) are arranged along the winding axis AX direction (Z-axis direction) of the conical coil 3. The As shown in FIG. 2B, the small-diameter loop-shaped conductor 31 having the smallest inner and outer diameters among the plurality of loop-shaped conductors is first than the other loop-shaped conductors (large-diameter loop-shaped conductor 32) in the Z-axis direction. Arranged close to main surface VS1.

Further, as shown in FIG. 2A, the small-diameter loop conductor 31 is disposed inside the opening BR surrounded by the large-diameter loop conductor 32 when viewed from the Z-axis direction. Further, the plurality of loop-shaped conductors (small-diameter loop-shaped conductor 31 and large-diameter loop-shaped conductor 32) do not overlap each other when viewed from the Z-axis direction.

In the present invention, “the plurality of loop-shaped conductors do not overlap each other when viewed from the winding axis direction” means that the plurality of loop-shaped conductors other than the portion where the plurality of loop-shaped conductors are connected via the interlayer connection conductor. This means that they do not overlap (do not cross) each other when viewed from the axial direction.

The change in the Z-axis direction of the inner and outer diameters of the plurality of loop-shaped conductors is one direction (see the outline DE of the conical coil 3 in FIG. 2B). In the present invention, “the change along the winding axis direction is one direction” means that the inner and outer diameters of the plurality of loop-shaped conductors change so as to increase (or decrease) along the Z-axis direction. Say.

Specifically, the small-diameter loop-shaped conductor 31 is disposed closer to the first main surface VS1 than the other loop-shaped conductors (large-diameter loop-shaped conductor 32) in the Z-axis direction. The large-diameter loop conductor 32 having the largest diameter is disposed farthest from the first main surface VS1 in the Z-axis direction as compared with the other loop-shaped conductors (small-diameter loop conductor 31). That is, as shown in the outline DE of the conical coil 3 in FIG. 2B, the inner and outer diameters of the plurality of loop conductors are directed in the + Z direction (from the first main surface VS1 side to the second main surface VS2 side). It has changed to become larger.

Next, an electronic device including the inductor bridge of the present invention will be described with reference to the drawings. FIG. 3 is a cross-sectional view illustrating a main part of the electronic apparatus 301 according to the first embodiment.

The electronic device 301 includes an inductor bridge 101A, a circuit board 71, and a mounting board 201. In the present embodiment, the circuit configured on the circuit board 71 corresponds to the “first circuit” in the present invention, and the circuit configured on the mounting board 201 corresponds to the “second circuit” in the present invention. The inductor bridge 101A differs from the inductor bridge 101 in that the insulating base material 10 includes a bent portion (bent portion) in part, and the other configurations are substantially the same.

As shown in FIG. 3, the inductor bridge 101A is connected to a circuit board 71 and a mounting board 201.

The metal body 2 is mounted on the upper surface of the mounting substrate 201, and a conductor 81 is formed on the upper surface of the mounting substrate 201. The receptacle 61 is connected to the conductor 81 and is electrically connected to a circuit configured on the mounting substrate 201. The mounting substrate 201 is, for example, a printed wiring board, and the metal body 2 is, for example, a shield case or a battery pack.

Further, a receptacle 62 is mounted on the lower surface of the circuit board 71. The receptacle 62 is electrically connected to a first circuit formed on the circuit board 71. The first circuit formed on the circuit board 71 is, for example, a radiating element of a UHF band antenna.

In the inductor bridge 101A, the connector 51 is connected to the receptacle 61, and the connector 52 is connected to the receptacle 62.

As shown in FIG. 3, the inductor bridge 101 A is arranged so that the first main surface VS 1 side of the insulating base 10 faces the main surface PS 1 of the mounting substrate 201. Therefore, the small-diameter loop conductor 31 is arranged closer to the metal body 2 than the other loop conductors (large-diameter loop conductor 32).

The inductor bridge 101A according to the present embodiment is manufactured by, for example, the following process. FIG. 4 is a cross-sectional view sequentially showing the manufacturing process of the inductor bridge 101A.

First, a laminated body is formed by laminating a base layer patterned with small-diameter loop conductors, large-diameter loop conductors, conductors, electrodes, etc., and after coating the protective layer, the insulating base material from the aggregate substrate state Individual element bodies are separated to obtain an inductor bridge 101 shown in (1) in FIG.

Next, as shown in (2) in FIG. 4, the first main surface VS1 and the second main surface of the insulating base 10 are formed along the Z-axis direction using the upper die 5 and the lower die 6. VS2 is heated and pressurized (see the arrow indicated by (2) in FIG. 4). The position to be heated and pressed is a position closer to the first end (the right end of the insulating base material) from the center in the longitudinal direction (X-axis direction) of the insulating base material 10. The upper mold 5 and the lower mold 6 have a structure in which a cross-sectional shape is bent into a predetermined shape.

Thereafter, the inductor bridge 101A is taken out from the upper mold 5 and the lower mold 6. By such a manufacturing method, an inductor bridge 101A having a bent portion (bent portion) is obtained.

The inductor bridges 101 and 101A according to the present embodiment have the following effects.

(A) In the present embodiment, the small-diameter loop conductor 31 is disposed closer to the metal body 2 than the large-diameter loop conductor 32 in the Z-axis direction with the inductor bridge 101 provided in the electronic device. . The small-diameter loop-shaped conductor 31 has the smallest inner and outer diameters among the plurality of loop-shaped conductors and a short line length, and therefore has a smaller conductor area than the other loop-shaped conductors (large-diameter loop-shaped conductor 32). Therefore, with this configuration, the stray capacitance generated between the conical coil 3 and the metal body 2 is smaller than when another loop conductor having a relatively large conductor area is disposed close to the metal body 2. .

(B) The magnetic field generated in the small-diameter loop conductor 31 whose line length is shorter than the other loop-shaped conductors is smaller than the magnetic field generated in the other loop-shaped conductors whose line length is longer than that of the small-diameter loop conductor 31. Therefore, with this configuration, the formation of the magnetic field is hardly hindered by the eddy current generated in the metal body 2. Therefore, an inductance bridge having a low-loss conical coil 3 and an electronic device 301 including the same can be realized with little reduction in inductance due to the proximity of the metal body 2.

(C) Moreover, in this embodiment, since the insulating base material 10 is a thermoplastic resin, as shown to (2) in FIG. 4, a shape is easy according to a mounting state (unevenness | corrugation etc. of a mounting destination). Plastic working (bending) is possible.

(D) In the present embodiment, the conical coil 3 is configured including the small-diameter loop conductor 31 and the large-diameter loop conductor 32 respectively formed on the plurality of base material layers 12 and 13. With this configuration, a conical coil having a predetermined number of turns and inductance can be formed on the insulating substrate 10.

(E) In the present embodiment, a plurality of loop conductors (small-diameter loop conductor 31 and large-diameter loop conductor 32) having different inner and outer diameters are arranged along the Z-axis direction. Further, the plurality of loop conductors (small diameter loop conductor 31 and large diameter loop conductor 32) do not overlap each other when viewed from the Z-axis direction. With this configuration, the loop-shaped conductors (small-diameter loop-shaped conductor 31 and large-diameter loop-shaped conductor 32) do not face each other, so that the interlayer capacitance between the plurality of loop-shaped conductors is small.

Next, the relationship between the inductor bridge 101 and the metal body 2 when an external force causing bending to the inductor bridge 101 is applied will be described with reference to the drawings. FIG. 5A is a partial cross-sectional view showing the relationship between the inductor bridge 101 and the metal body 2 before bending, and FIG. 5B shows the relationship between the inductor bridge 101 and the metal body 2 in a bent state. It is a fragmentary sectional view shown.

As shown in FIG. 5B, the inductor bridge 101 is bent in an L shape (with the first main surface VS1 side inward) along the longitudinal direction of the insulating base material 10. At this time, the second main surface VS2 side is deformed to be pulled by the bending displacement of the insulating base material 10, and the first main surface VS1 side is deformed to be compressed. Along with the tensile deformation on the second main surface VS2 side, the large-diameter loop conductor 32 positioned closer to the second main surface VS2 in the Z-axis direction extends toward both ends of the insulating base 10 in the longitudinal direction. Displacement (see hollow arrow DF2 in FIG. 5B). Further, along with the compressive deformation on the first main surface VS1 side, the small-diameter loop conductor 31 located closer to the first main surface VS1 in the Z-axis direction is displaced so as to contract (the hollow arrow DF1 in FIG. 5B). reference).

Therefore, even when the insulating substrate 10 is bent as shown in FIG. 5B, the small-diameter loop conductor 31 and the large-diameter loop conductor 32 do not overlap when viewed from the Z-axis direction (between surfaces). Therefore, the amount of change in the interlayer capacitance between the small-diameter loop conductor 31 and the large-diameter loop conductor 32 is small.

In the present invention, as shown in FIG. 5B, another loop conductor (large diameter loop conductor 32) having a relatively large conductor area is separated from the metal body 2 more than the small diameter loop conductor 31. Placed in a different position. Therefore, even when the inductor bridge 101 is bent and another loop conductor having a large conductor area (large diameter loop conductor 32) is deformed, the amount of change in the stray capacitance between the conical coil 3 and the metal body 2 is small. .

Furthermore, when the inductor bridge 101 is bent, the small-diameter loop conductor 31 is also deformed and the conductor area changes. However, with this configuration, the metal body 2 accompanying a change in the conductor area can be obtained as compared with the case where another loop conductor (large diameter loop conductor 32) having a relatively large conductor area is disposed close to the metal body 2. The amount of stray capacitance change between and is small.

The inductor bridge in the present invention may have the following configuration. 6A is a partial cross-sectional view of another inductor bridge 101A according to the first embodiment, and FIG. 6B is a partial cross-sectional view of an inductor bridge 101B of a comparative example. 6A and 6B, the thicknesses of the small-diameter loop conductors 31A and 31B and the large-diameter loop conductors 32A and 32B are exaggerated.

As shown in FIGS. 6A and 6B, the small-diameter loop conductors 31A and 31B and the large-diameter loop conductors 32A and 32B related to the inductor bridges 101A and 101B are connected to the inductor bridge 101 shown in FIG. The small-diameter loop conductor 31 and the large-diameter loop conductor 32 are thicker in the Z-axis direction. Specifically, the thickness in the Z-axis direction of the small-diameter loop conductors 31A and 31B and the large-diameter loop conductors 32A and 32B is thicker than the thickness in the Z-axis direction of each base material layer before lamination. The thickness T1 in the Z-axis direction of the insulating base material 10A of the inductor bridges 101A and 101B is equal to the thickness in the Z-axis direction of the insulating base material 10 of the inductor bridge 101 shown in FIG.

As shown in FIG. 6B, when the small-diameter loop conductor 31B and the large-diameter loop conductor 32B face each other, the distance L2 between the small-diameter loop conductor 31B and the large-diameter loop conductor 32B is The distance L1 between the small-diameter loop conductor 31A and the large-diameter loop conductor 32A is shorter (L1> L2). Therefore, when an external force causing bending is applied to the inductor bridge 101B of the comparative example, the amount of change in the interlayer capacitance of the conical coil 3B due to the deformation of the inductor bridge 101B is large. Furthermore, according to the present embodiment, the small-diameter loop-shaped conductor 31A and the large-diameter loop-shaped conductor 32A do not overlap when viewed from the Z-axis direction, and therefore the change in the interlayer capacitance of the conical coil 3A accompanying the deformation of the inductor bridge 101A. The amount is small.

Note that by increasing the thickness of the small-diameter loop conductor 31A and the large-diameter loop conductor 32A in the Z-axis direction, the portion where the conical coil 3A is formed becomes difficult to bend, and the mechanical strength against external force is increased. Furthermore, the DCR (direct current resistance) of the conical coil 3A can be reduced by increasing the thickness in the Z-axis direction of the small-diameter loop conductor 31A and the large-diameter loop conductor 32A.

<< Second Embodiment >>
In the second embodiment, a structure different from the electronic device shown in the first embodiment will be described.

FIG. 7 is a cross-sectional view showing a main part of the electronic device 302 according to the second embodiment.

The electronic device 302 includes an inductor bridge 102, a resin casing 91, and a mounting substrate 202. A conductor pattern 4 is formed on the inner surface of the resin casing 91. The conductor pattern 4 is, for example, a ground conductor.

In the present embodiment, the circuit configured on the mounting substrate 202 corresponds to the “first circuit” in the present invention, and the circuit (ground conductor) configured in the resin casing 91 corresponds to the “second circuit” in the present invention. To do.

As shown in FIG. 7, the inductor bridge 102 is connected to the conductor pattern 4 of the resin casing 91 and the conductor 82 of the mounting substrate 202. The inductor bridge 102 differs from the inductor bridge 101 according to the first embodiment in that a part of the inductor bridge is bent. Other configurations are substantially the same as those of the inductor bridge 101.

Conductors

82 and 84 are formed on the top surface of the mounting substrate 202, and a conductor 83 is formed inside the mounting substrate 202. The receptacle 62 is connected to the conductor 82 and is electrically connected to a circuit configured on the mounting substrate 202. The mounting board 202 is, for example, a printed wiring board. In the present embodiment, the conductor 84 is the “metal body” in the present invention.

Also, a receptacle 61 is mounted on the inner surface of the resin casing 91. The receptacle 61 is electrically connected to the conductor pattern 4 (ground conductor) formed in the resin casing 91.

The connector 51 of the inductor bridge 102 is connected to the receptacle 61, and the connector 52 is connected to the receptacle 62. The inductor bridge 102 is connected to the mounting substrate 202 and the resin casing 91, and as shown in FIG. 7, the small-diameter loop conductor 31 is more conductive than the other loop conductors (large-diameter loop conductor 32). 84 (metal body).

Further, in the inductor bridge 102, the portion where the conical coil 3 is formed is exposed from the opening OP1 formed in the resin casing 91. Therefore, the conical coil 3 is not shielded from the electromagnetic field. Therefore, this inductor bridge 102 can be used as an antenna, and communication with the outside becomes possible.

As shown in FIG. 7, the inductor bridge 102 is bent in an L shape at a portion where the conical coil 3 is not formed. Specifically, the inductor bridge 102 is connected to the mounting substrate 202 and the conductor pattern 4 of the resin casing 91, and the first end from the center in the longitudinal direction of the insulating base material 10C (the insulating base material 10C in FIG. 7). The position near the right end) is bent in an L shape with the first main surface VS1 inside.

At this time, with the bending displacement of the insulating base material 10C, the first main surface VS1 side is stressed in the −X direction, and the second main surface VS2 side is stressed in the + X direction. Therefore, the small-diameter loop conductor 31 positioned closer to the first main surface VS1 in the Z-axis direction is displaced so that its inner and outer diameters are reduced (see the hollow arrow DF1a in FIG. 7). Further, the large-diameter loop conductor 32 positioned closer to the second main surface VS2 in the Z-axis direction is displaced so that its inner and outer diameters are expanded (see the hollow arrow DF2a in FIG. 7).

Therefore, even when the inductor bridge 102 is bent as shown in FIG. 7, the small-diameter loop conductor 31 and the large-diameter loop conductor 32 do not overlap when viewed from the Z-axis direction. And the change in the interlayer capacitance between the large-diameter loop conductor 32 is small.

Thus, the small-diameter loop-shaped conductor 31 has an inner and outer diameter that is “relatively” along the insulating substrate 10 as compared with other loop-shaped conductors (large-diameter loop-shaped conductor 32) when the inductor bridge is bent. It is preferable to arrange in a contracted position.

In the present embodiment, the example in which the inductor bridge 102 is connected to the conductor pattern 4 formed on the inner surface of the resin casing 91 via the receptacle 61 is shown, but the present invention is not limited to this configuration. When the electronic device includes a metal casing, the inductor bridge may be connected to the metal casing by screwing or the like.

<< Third Embodiment >>
In the third embodiment, a structure in which the structure of the metal body is different from that of the electronic device shown in the second embodiment will be described.

FIG. 8 is a cross-sectional view showing a main part of an electronic device 303 according to the third embodiment.

The electronic device 303 includes an inductor bridge 103, a resin casing 92, and a mounting substrate 203. A conductor pattern 4 (ground conductor) is formed on the inner surface of the resin casing 92. In the present embodiment, the conductor pattern 4 formed on the inner surface of the resin casing 92 is the “metal body” in the present invention.

A conductor 82 is formed on the upper surface of the mounting substrate 203, and a conductor 83 is formed inside the mounting substrate 203.

As shown in FIG. 8, the inductor bridge 103 is connected to the conductor pattern 4 of the resin casing 92 and the conductor 82 of the mounting substrate 203. The inductor bridge 103 is the inductor bridge 102 according to the second embodiment in that the small-diameter loop conductor 31 is disposed closer to the conductor pattern 4 than the other loop conductors (large-diameter loop conductor 32). And different. Other configurations are substantially the same as those of the inductor bridge 102.

<< Fourth Embodiment >>
The fourth embodiment shows an example in which the structure of the conical coil is different from the inductor bridge shown in the first embodiment.

FIG. 9A is a plan view showing a portion where the conical coil 3C is formed in the inductor bridge 104 according to the fourth embodiment, and FIG. 9B is a cross-sectional view of that portion. In FIG. 9A, the protective layer 1 is not shown for easy understanding of the structure.

The inductor bridge 104 is different from the inductor bridge 101 according to the first embodiment in the structure of the conical coil. Other configurations are substantially the same as those of the inductor bridge 101. Hereinafter, a different part from 1st Embodiment is demonstrated.

In this embodiment, a large-diameter loop conductor 33C is formed on the surface of the base material layer 14. The large-diameter loop conductor 33C has a larger inner and outer diameter than the large-diameter loop conductor 32C and the small-diameter loop conductor 31C. The large-diameter loop conductor 32C has a larger inner and outer diameter than the small-diameter loop conductor 31C.

Inductor bridge 104 includes a rectangular conical coil of about 3.5 turns including small-diameter loop conductor 31C, large-

diameter loop conductors

32C and 33C, and interlayer connection conductors formed on a plurality of base material layers 12, 13, and 14, respectively. 3C is configured.

As shown in FIG. 9B, a plurality of loop conductors (small-diameter loop conductor 31C and large-

diameter loop conductors

32C and 33C) are arranged along the Z-axis direction. Among the plurality of loop conductors, the small-diameter loop conductor 31C having the smallest inner and outer diameters is disposed closer to the first main surface VS1 than the other loop conductors (large-

diameter loop conductors

32C and 33C) in the Z-axis direction. Has been.

Moreover, the change along the Z-axis direction of the inner and outer diameters of the plurality of loop-shaped conductors is one direction. Specifically, in the present embodiment, as shown in the outline DE of the conical coil shown in FIG. 9B, the inner and outer diameters of the plurality of loop conductors are in the + Z direction (from the first main surface VS1 side to the second main surface). It changes so as to increase toward the VS2 side.

Thus, there may be a plurality of “other loop conductors”. Even in this case, it is a condition that the plurality of loop-shaped conductors do not overlap each other when viewed from the Z-axis direction. In the present embodiment, the small-diameter loop conductor 31C is disposed inside the opening surrounded by the large-diameter loop conductor 32C, and the large-diameter loop conductor 32C is inside the opening surrounded by the large-diameter loop conductor 33C. Is arranged.

Note that, as shown in the present embodiment, the inner and outer diameters of the plurality of loop-shaped conductors are not limited to those that change uniformly along the Z-axis direction. That is, the inner and outer diameters of the plurality of loop-shaped conductors are not limited to those that change in one direction in proportion to the movement distance in the Z-axis direction. For example, the inner and outer diameters of four loop conductors (including small-diameter loop conductors) in the + Z direction (from the first main surface side to the second main surface side) are 2X → 4X → 5X → 8X (X is an arbitrary number) The configuration arranged along the Z-axis direction so as to be in this order is also included in the “change along the winding axis direction is one direction” in the present invention. In this case, it is a condition that the four loop-shaped conductors do not overlap each other when viewed from the Z-axis direction. On the other hand, the inner and outer diameters of four loop conductors (including small-diameter loop conductors) in the + Z direction (from the first main surface side to the second main surface side) are 2X → 5X → 3X → 4X (X is an arbitrary number) ) Are arranged along the Z-axis direction so as to be in the order of “), and are excluded from the state of“ the change along the winding axis direction is one direction ”in the present invention.

<< Fifth Embodiment >>
In the fifth embodiment, an example of a conical coil having a structure different from that of each of the embodiments described above is shown.

FIG. 10A is a plan view showing a portion where the conical coil 3D is formed in the inductor bridge 105 according to the fifth embodiment, and FIG. 10B is a cross-sectional view of that portion. In FIG. 10A, for easy understanding of the structure, the first coil portion CP1 is indicated by hatching, the second coil portion CP2 is indicated by a dot pattern, and the fourth coil portion CP4 is indicated by cross hatching.

The inductor bridge 105 is different from the inductor bridge 101 according to the first embodiment in the structure of a conical coil. Other configurations are substantially the same as those of the inductor bridge 101. Hereinafter, a different part from 1st Embodiment is demonstrated.

The conical coil 3C according to the present embodiment includes a large-diameter loop conductor 34D, a large-diameter loop conductor 33D, a large-diameter loop conductor 32D, a small-diameter loop conductor 31D, and an interlayer connection conductor (not shown). The The conical coil 3C has a winding axis AX that is orthogonal to the first main surface VS1 and the second main surface VS2 (parallel to the Z-axis direction).

Further, the conical coil 3C is wound more than 2 turns (about 3.5 turns) and has a first coil part CP1, a second coil part CP2, a third coil part CP3, and a fourth coil part CP4. The first coil portion CP1 is a portion that winds most inside the conical coil 3C when viewed from the Z-axis direction. The second coil portion CP2 is a portion that is first positioned toward the outer peripheral side with respect to the first coil portion CP1 when viewed from the Z-axis direction. The third coil portion CP3 is a portion that is secondly located toward the outer peripheral side with respect to the first coil portion CP1 when viewed from the Z-axis direction. The fourth coil portion is a portion located third from the first coil portion CP1 toward the outer peripheral side when viewed from the Z-axis direction.

In the present embodiment, as shown in FIG. 10 (A), a small-diameter loop conductor 31D of slightly more than 0.5 turns formed on the surface of the base material layer 11 is referred to as the first coil portion CP1. A one-turn large-diameter loop conductor 32D formed on the surface of the material layer 12 coincides with the second coil portion CP2. In the present embodiment, the one-turn large-diameter loop conductor 33D formed on the surface of the base material layer 13 coincides with the third coil portion CP3, and 1 formed on the surface of the base material layer 14 The large-diameter loop conductor 34D of the turn coincides with the fourth coil portion CP4.

As shown in FIG. 10A, the overall length of the first coil portion CP1 located on the innermost peripheral side is shorter than the other coil portions, and the overall length of the fourth coil portion CP4 is longer than the other coil portions. When the overall lengths of the coil portions are arranged in the long order, the fourth coil portion CP4, the third coil portion CP3, the second coil portion CP2, and the first coil portion CP1 are arranged in this order.

Further, as shown in FIGS. 10A and 10B, the line width T1 of the first coil portion CP1 is equal to the line width of the other coil portions (the line width T2 of the second coil portion CP2, the third coil). It is narrower than the line width T3 of the part CP3 and the line width T4 of the fourth coil part CP4. Further, the line width of the nth coil part is narrower than the line width of the (n + 1) th coil part. Specifically, the line width T2 of the second coil part CP2 is narrower than the line width T3 of the third coil part CP3, and the line width T3 of the third coil part CP3 is thinner than the line width T4 of the fourth coil part CP4. . When the line widths of the coil portions are arranged in order of narrowness, the first coil portion CP1, the second coil portion CP2, the third coil portion CP3, and the fourth coil portion CP4 become equivalent.

The inductor bridge 105 according to the present embodiment has the following effects in addition to the effects described in the first embodiment.

(A) In the present embodiment, the line width T1 of the first coil portion CP1 is equal to the line width of the other coil portions (the line width T2 of the second coil portion CP2, the line width T3 of the third coil portion CP3, and the fourth coil). It is narrower than the line width T4) of the part CP4. By reducing the line width T1 of the first coil portion CP1, the conductor area of the first coil portion CP1 closest to the metal body 2 can be reduced. Therefore, with this configuration, the facing area between the first coil portion CP1 and the metal body 2 can be reduced, and the line width of the other coil portions can be reduced (that is, the conductor area of the other coil portions can be reduced). ), Stray capacitance generated between the conical coil 3D and the metal body 2 can be further suppressed.

Also, with this configuration, the direct current resistance is reduced as compared with the case where the line widths of all the coil portions (the first coil portion CP1, the second coil portion CP2, the third coil portion CP3, and the fourth coil portion CP4) are reduced. The stray capacitance generated between the conical coil 3D and the metal body 2 can be effectively reduced while being reduced.

(B) In the present embodiment, the line width T2 of the second coil part CP2 is narrower than the line width T3 of the third coil part CP3, and the line width T3 of the third coil part CP3 is the line of the fourth coil part CP4. Narrower than width T4. That is, the line width of the nth coil part is narrower than the line width of the (n + 1) th coil part. The nth coil part is closer to the metal body 2 than the (n + 1) th coil part. Therefore, with this configuration, the stray capacitance generated between the conical coil 3D and the metal body 2 can be effectively reduced as compared with the case where the line width of the (n + 1) th coil part is narrower than the line width of the nth coil part. .

In the present embodiment, the conical coil 3D having four coil portions (the first coil portion CP1, the second coil portion CP2, the third coil portion CP3, and the fourth coil portion CP4) is shown, but the present invention is limited to this configuration. Is not to be done. The “conical coil” of the present invention may have an n-th coil portion (n is an integer of 2 or more). The n-th coil portion refers to a portion located at the (n−1) th position toward the outer peripheral side with respect to the first coil portion CP1 when viewed from the Z-axis direction.

<< Other Embodiments >>
In each embodiment shown above, although the example whose planar shape of an insulating base material is a rectangle was shown, it is not limited to this structure. The planar shape of the insulating substrate can be changed as appropriate within the scope of the effects and effects of the present invention, and may be, for example, a polygon, a circle, an ellipse, an L shape, a crank shape, a T shape, a Y shape, or the like. .

In each of the embodiments described above, an inductor bridge including an insulating base material formed by laminating four base material layers has been described. However, the present invention is not limited to this configuration. The number of base material layers forming the insulating base material can be appropriately changed within a range where the functions and effects of the present invention are exhibited. For example, the base material layer may be a single layer.

In each of the embodiments described above, an example in which a conical coil of about 1.5 turns or 2.5 turns is configured including loop-shaped conductors formed on a plurality of base material layers has been shown. It is not limited to. The number of turns of the conical coil provided in the inductor bridge can be changed as appropriate. Moreover, the outline of the conical coil viewed from the winding axis direction (Z-axis direction) may be, for example, a circle, an ellipse, a rectangle, or a polygon. Furthermore, in the above embodiment, an example of a conical coil including a small-diameter loop conductor and a large-diameter loop conductor of less than one turn has been shown. However, a spiral-shaped small-diameter loop conductor and a large-diameter loop including one or more turns are shown. You may comprise a conical coil including a conductor.

Moreover, in each embodiment shown above, although the example in which two connectors were provided on both the first main surface and the second main surface of the insulating base material was shown, it is not limited to this configuration. The two connectors may be provided only on the first main surface of the insulating base material, or may be provided only on the second main surface. Further, the arrangement and number of connectors can be appropriately changed depending on the circuit configuration of the inductor bridge.

In the present invention, the connector is not essential. You may connect a connection part to a 1st circuit, a 2nd circuit, etc. by electroconductive joining materials, such as solder, without using a connector.

Finally, the description of the above embodiment is illustrative in all respects and not restrictive. Modifications and changes can be made as appropriate by those skilled in the art. The scope of the present invention is shown not by the above embodiments but by the claims. Furthermore, the scope of the present invention includes modifications from the embodiments within the scope equivalent to the claims.

AP1 ... opening AX ... winding axis DE of conical coil ... general shape CP1 of conical coil ... first coil part CP2 ... second coil part CP3 ... third coil part CP4 ... fourth coil part BR ... opening OP1 ... opening PS1... Main surface V1, V2, V3 of mounting substrate. Interlayer connection conductor VS1. First main surface VS2. Second main surface W1. Insulating base material thickness 1. Protective layer 2.

Metal bodies

3, 3A, 3B, 3C. ... Conical coil 4 ... Conductor pattern (metal body)
5 ... Upper die 6 ... Lower die 10, 10A, 10B ... Insulating

base material

11, 12, 13, 14, 11a, 12a, 13a, 14a ... Base material layers 21, 22 ...

Conductors

31, 31A, 31B, 31C , 31D ... small-

diameter loop conductors

32, 32A, 32B, 32C, 32D, 33B, 33C, 33D, 34D ... large-

diameter loop conductors

31a, 32a, 33a, 34a ... loop-shaped

conductors

41, 42 ...

electrodes

51, 52 ...

Connectors

61, 62 ... Receptacle 71 ...

Circuit boards

81, 82, 83 ... Conductor 84 ... Conductor (metal body)
91, 92 ...

Resin casings

100, 101, 101A, 101B, 102, 103, 104, 105 ... Inductor bridges 201, 202, 203 ... Mounting

boards

301, 302, 303 ... Electronic equipment

Claims

An inductor bridge, a first circuit, a second circuit, and a metal body;
The first circuit and the second circuit are connected via the inductor bridge;
The inductor bridge is
An insulating base material having a first main surface and having flexibility;
A conical coil formed on the insulating substrate and having a winding axis perpendicular to the first main surface;
Have
The conical coil is configured to include a plurality of loop-shaped conductors arranged along the winding axis direction of the conical coil,
The change along the winding axis direction of the inner and outer diameters of the plurality of loop-shaped conductors is one direction,
The plurality of loop-shaped conductors do not overlap each other when viewed from the winding axis direction,
An electronic apparatus in which a small-diameter loop-shaped conductor having the smallest inner and outer diameters among the plurality of loop-shaped conductors is disposed closer to the metal body than other loop-shaped conductors.
Inductor bridge.
The electronic device according to claim 1, wherein the insulating base material is a laminate formed by laminating a plurality of base material layers made of a thermoplastic resin.
The electronic device according to claim 1, wherein the inductor bridge includes a bent portion in part.
The conical coil is wound more than 2 turns,
As viewed from the winding axis direction, the portion of the conical coil that winds most on the inner periphery is defined as a first coil portion, and n−1 (n is 2) toward the outer periphery with respect to the first coil portion. (The integer above) define the part located at the nth coil part,
The electronic device according to claim 1, wherein a line width of the first coil portion is narrower than a line width of other coil portions.
The electronic device according to claim 4, wherein a line width of the n-th coil part is narrower than a line width of the n + 1-th coil part.