JPWO2017057421A1 - Electronics - Google Patents

Abstract

An electronic device (101) includes a housing (1), a coil antenna (10) housed in the housing (1), having a winding shaft (AX1) and coil opening ends (E1, E2), and a housing (1) It is provided with the electroconductive member (21, 22) accommodated in. The conductive members (21, 22) have a first surface (S1) parallel to the winding axis (AX1) and close to the coil antenna (10). At least one of the coil opening ends (E1, E2) overlaps with the conductive members (21, 22) when viewed from the direction (X direction) perpendicular to the first surface (S1). The conductive member (21, 22) has a length (Z2) in a direction (Z direction) perpendicular to the winding axis (AX1) of the coil antenna (10) as viewed from the X direction. The length (Y2) in the winding axis (AX1) direction (Y direction) is longer than the length (Y1) of the coil antenna (10) (Y2 ≧ Y1). .

Description

  The present invention relates to an electronic device, and more particularly to an electronic device including a housing and a coil antenna housed in the housing.

  Conventionally, various electronic devices including a housing and a coil antenna housed in the housing have been devised.

  For example, Patent Document 1 discloses an electronic device including a housing, a coil antenna housed in the housing, and a base material that is housed in the housing and on which a planar conductor is formed. In the above electronic apparatus, the coil antenna is disposed so that the coil opening is close to the edge of the planar conductor, whereby the coil antenna and the planar conductor are electromagnetically coupled, and the planar conductor serves as a booster antenna for the coil antenna. Works.

International Publication No. 2012/033031

  However, in the coil antenna as shown in Patent Document 1, the magnetic flux passing through the coil opening forms a loop that wraps around from another direction to another coil opening, but the magnetic flux that is not linked to the coil antenna on the communication partner side is hardly used for communication. Does not contribute. For this reason, the presence of a magnetic flux that does not interlink with the coil antenna on the communication partner side reduces the coupling coefficient with the coil antenna on the communication partner side, which may deteriorate the communication characteristics.

  An object of the present invention is to provide an electronic apparatus including a coil antenna having a good coupling characteristic in which formation of a magnetic flux not interlinked with the coil antenna on the coupling partner side is suppressed with a simple configuration.

(1) The electronic device of the present invention
A housing,
A coil antenna housed in the housing, having a coil conductor wound around a winding axis, and having two coil open ends;
A conductive member housed in the housing, having a first surface parallel to the winding axis and close to the coil antenna;
With
At least one of the two coil opening ends overlaps with the conductive member when viewed from a direction perpendicular to the first surface,
The conductive member is characterized in that a length in the winding axis direction is not less than a length of the coil antenna when viewed from a direction perpendicular to the first surface.

  With this configuration, the generation of magnetic flux that exits from one coil opening of the coil antenna in the direction in which the conductive member exists and enters the other coil opening is suppressed. On the contrary, the density of the magnetic flux in the direction in which the conductive member does not exist increases. Therefore, the generation of magnetic flux that does not contribute to the coupling with the coil antenna on the coupling partner side is suppressed, and the density of the magnetic flux interlinking with the coil antenna on the coupling partner side is increased. Therefore, an electronic device including a coil antenna with good coupling characteristics can be realized with a simple configuration.

(2) In the above (1), it is preferable that the conductive member is longer in the direction perpendicular to the winding axis than the coil antenna when viewed from the direction perpendicular to the first surface. With this configuration, generation of magnetic flux that does not contribute to coupling with the coil antenna on the coupling partner side is further suppressed, and the density of magnetic flux interlinking with the coil antenna on the coupling partner side is further increased.

(3) In the above (1) or (2), the number of the conductive members is two, and the first surfaces of the two conductive members are arranged to face each other with the coil antenna interposed therebetween. It is preferable. With this configuration, it is possible to increase the density of the magnetic flux that exits from one coil opening in a direction in which no conductive member exists and enters the other coil opening. Therefore, an electronic device having directivity in a direction in which no conductive member exists can be realized.

(4) In any one of the above (1) to (3), a distance between the coil antenna and the conductive member is shorter than a width of the coil antenna in a direction perpendicular to the first surface. preferable. In this configuration, since the coil antenna and the conductive member are disposed sufficiently close to each other, the effect of suppressing the magnetic flux that does not contribute to the coupling can be further enhanced.

(5) In any one of the above (1) to (4), the length of the conductive member in the direction perpendicular to the first surface is longer than the width of the coil antenna in the direction perpendicular to the first surface. It is preferable. With this configuration, since the outer peripheral length of the conductive member is increased, generation of magnetic flux that exits from one coil opening of the coil antenna in the direction in which the conductive member exists and enters the other coil opening is further suppressed.

(6) In any one of the above (1) to (5), the conductive member is preferably a component including a conductor housed in the housing. In this configuration, the conductive member can be easily configured by using a component including a conductor formed on the circuit board. In addition, it is not necessary to separately dispose the conductive member for that purpose, so that the manufacture is easy and the cost can be reduced.

(7) In any one of (1) to (5), the conductive member is preferably a part of the casing. With this configuration, it is not necessary to separately dispose the conductive member, so that the manufacturing is easy and the cost can be reduced.

(8) In any one of (1) to (7), the coil antenna preferably has a rectangular parallelepiped outer shape. With this configuration, the entire end surface of the coil antenna that is a plane is close to the first surface of the conductive member. Therefore, the generation of magnetic flux that exits from the one coil opening of the coil antenna in the direction in which the conductive member exists and enters the other coil opening is effectively suppressed.

  ADVANTAGE OF THE INVENTION According to this invention, an electronic device provided with the coil antenna with favorable coupling | bonding characteristics by which formation of the magnetic flux which is not linked to the coil antenna of a coupling | bonding other party was suppressed by the simple structure was suppressed.

FIG. 1 is a plan view of an electronic apparatus 101 according to the first embodiment. 2A is a cross-sectional view taken along line AA in FIG. 1, and FIG. 2B is a cross-sectional view taken along line BB in FIG. 3A is a plan view of the electronic device 100 that does not include a conductive member in the housing 1, and FIG. 3B is a cross-sectional view taken along the line CC in FIG. 3A. FIG. 3C is a sectional view taken along the line DD in FIG. FIG. 4 is a diagram showing a state of magnetic flux generated from the coil antenna 10 in the AA sectional view in FIG. FIG. 5A is a plan view of the electronic device 102 according to the second embodiment, and FIG. 5B is a cross-sectional view taken along line EE in FIG. FIG. FIG. 6A is a plan view of the electronic apparatus 103 according to the third embodiment, and FIG. 6B is a cross-sectional view taken along line FF in FIG. FIG. 7A is a plan view of the electronic apparatus 104 according to the fourth embodiment, and FIG. 7B is a cross-sectional view taken along line GG in FIG. FIG. 8A is a plan view of the electronic device 105 according to the fifth embodiment, and FIG. 8B is a front view of the electronic device 105. 9A is a cross-sectional view taken along the line HH in FIG. 8A, and FIG. 9B is a cross-sectional view taken along the line JJ in FIG. 8B.

  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. Each embodiment is an exemplification, and a partial replacement or combination of the configurations shown in different embodiments is possible.

<< First Embodiment >>
FIG. 1 is a plan view of an electronic apparatus 101 according to the first embodiment. 2A is a cross-sectional view taken along line AA in FIG. 1, and FIG. 2B is a cross-sectional view taken along line BB in FIG. In FIG. 1, FIG. 2 (A), and FIG. 2 (B), the structure of the electronic device 101 is illustrated in a simplified manner for easy understanding of the drawings and the principle. The electronic device 101 is, for example, a mobile phone (including a smartphone), a wearable terminal (such as a smart watch), a notebook computer, a tablet terminal, a PDA, a camera, a game machine, a toy, an RFID tag, or the like.

  The electronic device 101 includes a housing 1, a circuit board 2, a coil antenna 10, and two conductive members 21 and 22.

  The housing 1 has a rectangular parallelepiped shape in plan view. The housing 1 is, for example, a resin housing, but a part thereof may be made of metal. The circuit board 2, the coil antenna 10, and the two conductive members 21 and 22 are all housed in the housing 1.

  The circuit board 2 is a square plate and has a planar conductor 3 inside. The coil antenna 10 has a coil conductor 11 wound around the winding axis AX1, has two coil opening ends E1 and E2, and is mounted on the upper surface of the circuit board 2. The coil antenna 10 according to the present embodiment is a helical coil in which a coil conductor 11 is wound a plurality of times around a magnetic core 12 having a rectangular parallelepiped outer shape. That is, the coil antenna 10 is a chip-type coil antenna. The end surfaces of the coil antenna 10 (the left and right surfaces of the coil antenna 10 in FIG. 2A) are in relation to the upper surface of the circuit board 2 and the first surface of the housing 1 (the lower surface of the housing 1 in FIG. 2A). Are arranged vertically. The circuit board 2 is, for example, a printed wiring board, and the planar conductor 3 is, for example, a ground conductor pattern. Further, the winding axis AX1 is parallel to the Y direction as shown in FIG.

  The “two coil open ends” in the present invention refers to a portion where a magnetic flux is strongly radiated in a coil antenna. That is, in the case where a plurality of coil conductors 11 are wound around the magnetic core 12 as in the coil antenna 10 according to the present embodiment, both ends of the magnetic core 12 in the winding axis AX1 direction (Y direction). This part is referred to as “two coil open ends”. When the magnetic core is disposed on the inner side of the coil conductor 11 positioned on the outermost side in the Y direction, the coil conductor positioned on the outermost side in the Y direction is defined as “two coil openings” in the present invention. Say "End".

  The two conductive members 21 and 22 have a rectangular parallelepiped shape formed of a member having at least a surface having conductivity, and are mounted on the upper surface of the circuit board 2. The conductive members 21 and 22 have a first surface S1 parallel to the Y direction and the Z direction. The first surfaces S1 of the conductive members 21 and 22 are parallel to the winding axis AX1 and close to the coil antenna 10. Further, the first surfaces S1 of the conductive members 21 and 22 are disposed to face each other with the coil antenna 10 interposed therebetween, as shown in FIG. The conductive members 21 and 22 are not arranged in the winding axis AX1 direction (Y direction) of the coil antenna 10. Therefore, the conductive members 21 and 22 do not disturb the magnetic flux that exits from the coil opening on one side (coil opening end E1 side) of the coil antenna 10 and the magnetic flux that enters the coil opening on the other side (coil opening end E2 side). If the conductive member is arranged so as to be charged and separated from the coil opening so as not to disturb the magnetic flux (if it is not arranged near the coil opening), the conductive member is arranged in the direction of the winding axis AX1 of the coil antenna 10. It may be arranged. However, the conductive member is preferably not arranged in the direction of the winding axis AX1 of the coil antenna 10 in order to suppress the magnetic flux from being blocked as much as possible. The conductive members 21 and 22 have conductors facing the coil antenna 10 such as conductor parts such as connector frames and shield cases housed in the housing 1 or parts including conductors such as electrolytic capacitors and battery packs. It is a part.

  Here, “the first surface S1 of the conductive members 21 and 22 is“ close to the coil antenna ”does not mean that the conductive members 21 and 22 and the coil antenna 10 are simply present in the immediate vicinity. . The case where 1st surface S1 is located nearest to the coil antenna 10 from any part of the electroconductive members 21 and 22 is said.

  As shown in FIG. 2B, the conductive member 21 has a length Z2 in the direction (Z direction) perpendicular to the winding axis AX1 when viewed from the direction (X direction) perpendicular to the first surface S1. The antenna 10 is longer than the length Z1 (Z2> Z1), and the length Y2 in the Y direction is longer than the length Y1 of the coil antenna 10 (Y2> Y1). Further, the two coil opening ends E1 and E2 of the coil antenna 10 both overlap the conductive member 21 when viewed from the X direction.

  2A, the distance X2 between the coil antenna 10 and the conductive member 21 is shorter than the width X1 of the coil antenna 10 in the X direction (X2 <X1). Furthermore, the length X3 of the conductive member 21 in the X direction is longer than the width X1 of the coil antenna 10 in the X direction (X3> X1).

  In FIGS. 2A and 2B, only the relationship between the coil antenna 10 and the conductive member 21 is shown. However, the relationship between the coil antenna 10 and the conductive member 22 is similarly described above. Holds.

  Next, an electronic apparatus that does not include the conductive members 21 and 22 in the housing 1 will be described as a comparative example. 3A is a plan view of the electronic device 100 that does not include a conductive member in the housing 1, and FIG. 3B is a cross-sectional view taken along the line CC in FIG. 3A. FIG. 3C is a sectional view taken along the line DD in FIG. FIG. 4 is a diagram showing a state of magnetic flux generated from the coil antenna 10 in the AA sectional view in FIG.

  The coil antenna 10 is mounted on the upper surface of the circuit board 2. The coil antenna 41 is a coil antenna on the coupling partner side that communicates with the electronic device 100.

  Usually, the magnetic flux generated from the coil antenna 10 of the electronic device 100 exits from one coil opening in all directions, wraps around, and enters the other coil opening (FIGS. 3A, 3B, and 3C). ) (See magnetic fluxes φa, φi). Of the magnetic fluxes φa and φi generated from the coil antenna 10, only a part of the magnetic flux φa (magnetic flux contributing to the coupling) linked to the coil antenna 41 on the coupling partner side is present. 41 becomes low, and communication is impossible due to a decrease in induced electromotive force generated in the coil antenna 41 on the coupling partner side, or a communicable distance is shortened. In addition, since the circuit board 2 has the planar conductor 3 inside, generation | occurrence | production of the magnetic flux which wraps around in the direction (-Z direction of the coil antenna 10) where the planar conductor 3 exists is suppressed.

  On the other hand, in the electronic apparatus 101 according to the present embodiment, the conductive members 21 and 22 are not arranged in the direction of the winding axis AX1 of the coil antenna 10. The first surfaces S1 of the conductive members 21 and 22 are disposed to face each other with the coil antenna 10 interposed therebetween. Therefore, from one coil opening of the coil antenna 10, the conductive members 21 and 22 and the planar conductor 3 are present in the directions (the + X direction, the −X direction, and the −Z direction of the coil antenna 10 in FIG. 4), Generation of magnetic flux entering the other coil opening is suppressed. On the contrary, the density of the magnetic flux φa in the direction where the conductive members 21 and 22 and the planar conductor 3 do not exist (the + Z direction of the coil antenna 10) is relatively high.

  Therefore, the magnetic flux φa linked to the coil antenna 41 on the coupling partner side, that is, the density of the magnetic flux contributing to the coupling is increased, so that the coupling coefficient between the coil antenna 10 and the coil antenna 41 on the coupling partner side is increased. The induced electromotive force generated in the coil antenna 41 on the coupling partner side is increased, so that the communication characteristics can be improved or the communicable distance can be increased.

  The electronic device according to this embodiment has the following effects.

(A) In the electronic device 101 according to the present embodiment, the generation of magnetic flux that does not contribute to coupling is suppressed, and the magnetic flux φa linked to the coil antenna 41 on the coupling partner side, that is, the density of magnetic flux that contributes to coupling increases. Therefore, the electronic device 101 including the coil antenna 10 with good coupling characteristics can be realized with a simple configuration.

(B) In the electronic device 101, the first surfaces S1 of the two conductive members 21 and 22 are disposed to face each other with the coil antenna 10 interposed therebetween. With this configuration, the density of the magnetic flux φa that exits from one coil opening in the direction in which the conductive members 21 and 22 do not exist and enters the other coil opening can be increased. Therefore, an electronic device having directivity in a direction in which the conductive members 21 and 22 are not present can be realized.

(C) In the electronic device 101, since the distance X2 between the coil antenna 10 and the conductive member 21 is shorter than the width X1 of the coil antenna 10 in the X direction (X2 <X1), the coil antenna 10 and the conductive member Since 21 is arranged sufficiently close to the magnetic flux 21, the effect of suppressing the magnetic flux that does not contribute to the coupling can be further enhanced.

(D) In the electronic device 101, since the length X3 of the conductive member 21 in the X direction is longer than the width X1 of the coil antenna 10 in the X direction (X3> X1), the outer peripheral length of the conductive member 21 is long. Generation of magnetic flux (magnetic flux that does not contribute to coupling) that exits from one coil opening of the coil antenna 10 in the direction in which the conductive member 21 exists and enters the other coil opening is further suppressed.

(E) In the electronic device 101, the conductive members 21 and 22 are components including a conductor housed in the housing 1. In this configuration, the conductive members 21 and 22 can be easily configured by using a conductor formed on the circuit board 2. In addition, since the conductive members 21 and 22 do not need to be separately disposed therefor, the manufacturing is easy and the cost can be reduced. In addition, the space in the housing can be effectively used.

(F) In the electronic device 101, the coil antenna 10 has a rectangular parallelepiped outer shape. In this configuration, since the coil antenna 10 has a rectangular parallelepiped shape, the entire end surface of the coil antenna 10 that is a plane is close to the first surface S1 of the conductive members 21 and 22 (assuming that the outer shape of the coil antenna 10 is cylindrical or parallel). If it is a hexahedron shape, the entire end surface of the coil antenna 10 will not be close to the first surface S1 of the conductive members 21, 22. Therefore, the generation of magnetic flux that exits from the one coil opening of the coil antenna in the direction in which the conductive member exists and enters the other coil opening is effectively suppressed.

<< Second Embodiment >>
In the second embodiment, an example in which the number of conductive members housed in the housing 1 is different from that in the first embodiment is shown.

  FIG. 5A is a plan view of the electronic device 102 according to the second embodiment, and FIG. 5B is a cross-sectional view taken along line EE in FIG. FIG.

  The electronic device 102 is different from the electronic device 101 according to the first embodiment in that the electronic device 102 is housed in the housing 1 and has one conductive member mounted on the upper surface of the circuit board 2. Other configurations are the same as those of the electronic apparatus 101. Hereinafter, parts different from the electronic device 101 will be described.

  In the electronic device 102, the first surface S1 of the conductive member 21 is disposed in the vicinity of the coil antenna 10, and the circuit board 2 has the planar conductor 3 therein. Therefore, it exits from one coil opening of the coil antenna 10 in the direction in which the conductive member 21 and the planar conductor 3 exist (the −X direction and the −Z direction of the coil antenna 10 in FIG. 5B), and the other Generation of magnetic flux entering the coil opening is suppressed. Conversely, the densities of the magnetic fluxes φa and φi in the direction in which the conductive member 21 and the planar conductor 3 do not exist (the + X direction and the + Z direction of the coil antenna 10) increase.

  Even in such a configuration, the magnetic flux φa linked to the coil antenna 41 on the coupling partner side, that is, the density of the magnetic flux contributing to the coupling increases, so that the coupling coefficient between the coil antenna 10 and the coil antenna 41 on the coupling partner side increases. As a result, the connectable distance can be increased.

  As shown in the present embodiment, the number of conductive members stored in the housing 1 may be one. Conversely, the number, shape, structure, and the like of the conductive member can be changed as appropriate within the scope of the operations and effects of the present invention. That is, the number of conductive members may be three or more. In addition, the three-dimensional shape of the conductive member can be changed as appropriate, such as a cubic shape, a cylindrical shape, a polygonal pyramid shape, a spherical shape, and a bowl shape. Also, the planar shape of the conductive member can be appropriately changed to, for example, a square, a rectangle, a circle, an ellipse, an L shape, a T shape, or the like. In addition, 1st surface S1 of the electroconductive members 21 and 22 is not limited to a plane, You may have a curved surface.

  As shown in this embodiment, an electronic device having directivity in a predetermined direction can be realized by appropriately changing the number, shape, structure, and the like of the conductive member.

<< Third Embodiment >>
In the third embodiment, an electronic apparatus 103 including a magnetic field antenna is described. A magnetic field type antenna is an antenna that radiates magnetic flux, and is an antenna used for near field communication (near field communication) by magnetic field coupling with an antenna on the communication partner side. The magnetic field antenna is used for communication such as NFC (Near Field Communication).

  FIG. 6A is a plan view of the electronic apparatus 103 according to the third embodiment, and FIG. 6B is a cross-sectional view taken along line FF in FIG.

  The electronic device 103 is different from the electronic device 101 according to the first embodiment in that the conductive patterns 4A and 4B, the RFIC element 51, and the capacitor 52 are provided, and the circuit board 2 does not have a planar conductor. The electronic device 103 is different from the electronic device 101 in the size of the conductive member 22. Other configurations are substantially the same as those of the electronic device 101. Hereinafter, parts different from the electronic device 101 will be described.

  The RFIC element 51 and the capacitor 52 are mounted on the upper surface of the circuit board 2, and conductor patterns 4 </ b> A and 4 </ b> B are formed on the upper surface of the circuit board 2. The RFIC element 51 is, for example, a packaged RFIC chip (bare chip) for an RFID tag, but may be a bare chip RFIC. The capacitor 52 is, for example, a multilayer ceramic chip component. The capacitor 52 may be a lead component or a bridge component. Conductor patterns 4A and 4B are metal foil patterns, such as Cu foil, for example.

  The first end of the coil conductor 11 is connected to the power supply terminal of the RFIC element 51 via the conductor pattern 4A, and the second end of the coil conductor 11 is connected to the power supply terminal of the RFIC element 51 via the conductor pattern 4B. A first end of the capacitor 52 is connected to the conductor pattern 4A, and a second end of the capacitor 52 is connected to the conductor pattern 4B.

  With this configuration, the coil antenna 10 is connected to the RFIC element 51, and the capacitor 52 is connected in parallel to the coil antenna 10. The coil antenna 10, the capacitor 52, and the capacitance component inside the RFIC element 51 constitute an LC resonance circuit. The capacitance of the capacitor 52 is a frequency at which the resonance frequency of the LC resonance circuit or the resonance frequency considering the frequency fluctuation of the LC resonance circuit due to the arrangement of the conductive members 21 and 22 is substantially equal to the communication frequency of the RFID system (for example, 13.56 MHz) is selected. A plurality of capacitors 52 may be provided.

  The conductive member 22 according to this embodiment is larger than the conductive member 21. The conductive member 22 is, for example, a battery pack.

  Even with such a configuration, an electronic device including the coil antenna 10 with good coupling characteristics can be realized, as with the electronic device 101 according to the first embodiment.

  As shown in this embodiment, the planar conductor of the circuit board 2 is not essential in the present invention. Since the electronic device 103 does not have a planar conductor, the magnetic flux density in the direction in which the conductive members 21 and 22 do not exist (the + Z direction and the −Z direction of the coil antenna 10 in FIG. 6B) is high. Therefore, an electronic device having directivity in a direction in which the conductive members 21 and 22 are not present can be realized.

  In addition, since the inductance of the coil antenna 10 is reduced by arranging the conductive members 21 and 22 close to the coil antenna 10, the resonance frequency of the LC resonance circuit can be reduced by using a larger coil antenna. It can also be set. Even in this case, the use of a coil antenna with a large coil opening or a large number of winding axes increases the density of magnetic flux (magnetic flux contributing to coupling) linked to the coil antenna on the coupling partner side. The coupling coefficient with the other party's coil antenna is increased, the communication characteristics are improved, or the communicable distance can be increased.

<< Fourth Embodiment >>
FIG. 7A is a plan view of the electronic apparatus 104 according to the fourth embodiment, and FIG. 7B is a cross-sectional view taken along line GG in FIG.

  The electronic device 104 is different from the electronic device 103 according to the third embodiment in the shape of the circuit board 2 and the structure of the conductive member 22. Other configurations are the same as those of the electronic device 103. Hereinafter, parts different from the electronic device 103 will be described.

  The circuit board 2 according to the present embodiment has a rectangular shape whose longitudinal direction coincides with the Y direction. The conductive member 22 is not mounted on the upper surface of the circuit board 2.

  Even with such a configuration, an electronic device including the coil antenna 10 with good coupling characteristics can be realized, as with the electronic device 101 according to the first embodiment.

  As shown in the present embodiment, the circuit board 2 is not essential in the present invention. The conductive members 21 and 22 and the coil antenna 10 do not need to be mounted on the upper surface of the circuit board 2 and may be fixed to the housing 1 or the like.

<< Fifth Embodiment >>
In the fifth embodiment, an example in which a part of the casing is used as a conductive member is shown.

  FIG. 8A is a plan view of the electronic device 105 according to the fifth embodiment, and FIG. 8B is a front view of the electronic device 105. 9A is a cross-sectional view taken along the line HH in FIG. 8A, and FIG. 9B is a cross-sectional view taken along the line JJ in FIG. 8B.

  The electronic device 105 includes a housing 1 </ b> A, a circuit board 2, a coil antenna 10, and one conductive member 21. The electronic device 105 is different from the electronic device 103 according to the third embodiment in the structure of the housing 1A and the arrangement of the coil antenna 10. Other configurations are substantially the same as those of the electronic device 103. The electronic device 105 includes the conductor patterns 4A and 4B, the RFIC element 51, the capacitor 52, and the like shown in FIG. Hereinafter, parts different from the electronic device 103 will be described.

  The casing 1A has a rectangular parallelepiped shape in plan view. As shown in FIG. 9A, the housing 1A includes a cylindrical frame portion 5 having a rectangular shape when viewed from the Z direction, and an upper lid portion 6 and a lower lid portion 7 that are rectangular flat plates. The The frame portion 5 is made of, for example, metal, and the upper lid portion 6 and the lower lid portion 7 are, for example, resin flat plates.

  In the present embodiment, the conductive member 21 and the frame portion 5 correspond to the “conductive member” in the present invention.

  The coil antenna 10 is mounted on the upper surface of the circuit board 2. The coil antenna 10 is disposed in the vicinity of the first surface S1 of the frame portion 5 (the left inner surface of the frame portion 5 in FIG. 9B) when viewed from the Z-axis direction. The first surface S1 of the conductive member 21 and the first surface S1 of the frame portion 5 are parallel to the winding axis of the coil antenna, as shown in FIGS. 9A and 9B, and the like. Close to the coil antenna. The first surface S1 of the conductive member 21 and the first surface S1 of the frame portion 5 are opposed to each other with the coil antenna 10 interposed therebetween.

  Even with such a configuration, an electronic device including the coil antenna 10 with good coupling characteristics can be realized, as with the electronic device 103 according to the third embodiment.

  As shown in the present embodiment, the conductive member may be a part of the housing. With this configuration, it is not necessary to separately dispose the conductive member, so that the manufacturing is easy and the cost can be reduced. Further, as shown in the present embodiment, the housing may be composed of a resin member and a metal member.

  When the conductive member is a part of the housing, the shape of the conductive member is not limited to a cylindrical shape like the frame portion 5 and may be appropriately selected within the scope of the effects and advantages of the present invention. It can be changed.

<< Other Embodiments >>
In the above-described embodiment, the case 1 has an example in which the planar shape is a rectangular parallelepiped, but the configuration is not limited to this configuration. The shape, structure, and the like of the housing 1 can be changed as appropriate within a range where the functions and effects of the present invention are exhibited. The three-dimensional shape of the housing 1 can be changed as appropriate, such as a cubic shape, a cylindrical shape, a polygonal pyramid shape, a spherical shape, and a bowl shape. Further, the planar shape of the housing 1 can be changed as appropriate, for example, rectangular, circular, elliptical, L-shaped, T-shaped, and the like.

  In the above-described embodiment, an example in which the circuit board 2 housed in the housing 1 is a square / rectangular flat plate is shown, but the present invention is not limited to this configuration. The shape, number, structure, etc. of the circuit board 2 can be changed as appropriate. There may be a plurality of circuit boards 2 accommodated in the housing 1, for example, and the shape can be appropriately changed to a circle, an ellipse, an L shape, a Y shape, or the like. The circuit board 2 is not limited to a flat plate, but may be a three-dimensional structure such as a multilayer board. As described above, the circuit board 2 is not essential in the present invention.

  In the above-described embodiment, the configuration example in which the two coil opening ends E1 and E2 of the coil antenna 10 both overlap the conductive member 21 when viewed from the X direction has been described. However, the configuration is limited to this configuration. is not. When at least one of the two coil opening ends E1 and E2 overlaps with the conductive member when viewed from the X direction, an electronic device including the coil antenna 10 with good coupling characteristics can be realized. However, in order to enhance the function and effect of the present invention, it is preferable that the two coil opening ends E1 and E2 overlap with the conductive member when viewed from the X direction.

  In the above-described embodiment, an example in which the coil antenna 10 is a helical coil in which the coil conductor 11 is wound around a rectangular parallelepiped magnetic core has been described. However, the present invention is not limited to this configuration. In order to increase the mechanical strength of the coil antenna 10, a nonmagnetic ferrite ceramic may be provided outside the coil conductor 11. The coil antenna 10 may use a non-magnetic core instead of the magnetic core 12, and may be an air core without using the magnetic core 12. However, the presence of the magnetic core 12 makes it possible to obtain a coil antenna having a predetermined inductance value without increasing the size. When a non-magnetic core is used instead of the magnetic core 12, or when the core is an air core, the coil conductor 11 wound around the winding axis AX1 over a plurality of turns is wound. The coil conductor 11 located on the outermost side in the direction of the axis AX1 (Y direction) is referred to as “two coil opening ends” in the present invention.

  In the above-described embodiment, when the conductive member is viewed from the direction (X direction) perpendicular to the first surface S1, the length Y2 in the winding axis AX1 direction (Y direction) is larger than the length Y1 of the coil antenna 10. Although a long (Y2> Y1) configuration example is shown, the configuration is not limited to this. The conductive member only needs to have a length Y2 in the Y direction that is equal to or longer than the length Y1 of the coil antenna 10 as viewed from the X direction. However, in order to enhance the function and effect of the present invention, it is preferable that the length of the conductive member Y2 in the Y direction is longer than the length Y1 of the coil antenna 10 as viewed from the X direction.

  In the above-described embodiment, the electronic apparatus including the coil antenna 10 in the communication system mainly using magnetic field coupling such as NFC has been described. However, the coil antenna 10 and the electronic apparatus in the above-described embodiment utilize magnetic field coupling. The contactless power transmission system (electromagnetic induction method, magnetic field resonance method) can be used. That is, the coil antenna 10 in the above-described embodiment can be applied as a power transmission antenna device in a power transmission device of a non-contact power transmission system or a power reception antenna device in a power reception device.

AX1 ... winding axes E1 and E2 of the coil antenna ... coil opening end S1 ... first surface X1 of the conductive member ... width X2 of the coil antenna in a direction perpendicular to the first surface ... between the coil antenna and the conductive member Distance X3: Length Y1 of the conductive member in the direction perpendicular to the first surface. Length of the coil antenna Y2 in the winding axis direction when viewed from the direction perpendicular to the first surface. From the direction perpendicular to the first surface. As viewed from the direction perpendicular to the first surface, the length Z1 of the conductive member in the winding axis direction. From the direction perpendicular to the first surface, the length Z2 of the coil antenna in the direction perpendicular to the winding axis. As viewed, the length 1, 1A of the conductive member in the direction perpendicular to the winding axis 1, the casing 2, 2A, the circuit board 3, the planar conductors 4A, 4B, the conductive pattern 5, the frame (conductive member).
6 ... Upper lid portion 7 ... Lower lid portion 10 ... Coil antenna 11 ... Coil conductor 12 ... Magnetic cores 21, 22 ... Conductive member 41 ... Coil antenna 51 ... RFIC element 52 ... Capacitors 100, 101, 102, 103, 104, 105: Electronic equipment

Claims (8)

A housing,
A coil antenna housed in the housing, having a coil conductor wound around a winding axis, and having two coil open ends;
A conductive member housed in the housing, having a first surface parallel to the winding axis and close to the coil antenna;
With
At least one of the two coil opening ends overlaps with the conductive member when viewed from a direction perpendicular to the first surface,
The electrically conductive member is an electronic device having a length in the winding axis direction that is equal to or greater than a length of the coil antenna when viewed from a direction perpendicular to the first surface.   2. The electronic device according to claim 1, wherein the conductive member has a length in a direction perpendicular to the winding axis that is longer than the coil antenna when viewed from a direction perpendicular to the first surface. The conductive member is two,
3. The electronic device according to claim 1, wherein the first surfaces of the two conductive members are disposed to face each other with the coil antenna interposed therebetween.   4. The electronic device according to claim 1, wherein a distance between the coil antenna and the conductive member is shorter than a width of the coil antenna in a direction perpendicular to the first surface.   5. The electronic device according to claim 1, wherein a length of the conductive member in a direction perpendicular to the first surface is longer than a width of the coil antenna in a direction perpendicular to the first surface.   The electronic device according to claim 1, wherein the conductive member is a component including a conductor housed in the housing.   The electronic device according to claim 1, wherein the conductive member is a part of the housing.   The electronic device according to claim 1, wherein the coil antenna has a rectangular parallelepiped outer shape.

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