JP5288653B2 - Non-contact wireless communication coil and portable wireless terminal - Google Patents

Description

  The present invention relates to a coil for contactless wireless communication capable of contactless wireless communication and a portable wireless terminal equipped with the coil.

  For example, portable wireless terminals such as mobile phone terminals and smart phones are equipped with non-contact wireless communication (so-called RFID (Radio Frequency IDentification)) functions such as NFC (Near Field Communication) including FeliCa (registered trademark). doing. This kind of contactless wireless communication realizes an electronic money function, a ticket function, and the like.

  In recent years, portable wireless terminals equipped with a function of charging a battery (contactless charging) by transmitting power in a contactless manner are being used. Non-contact power transmission methods include an electromagnetic induction method, a magnetic field resonance method, and the like, and a method that performs power transmission with a coil on a power feeding side and a coil on a power receiving side facing each other is the mainstream.

  In portable wireless terminals equipped with a non-contact charging function, those in which a charging coil is integrated with a battery pack are mainly used. For this reason, when it is going to make a battery pack thin for further thickness reduction of a terminal, there exists a big subject that battery capacity decreases. On the other hand, when the charging coil is configured separately from the battery pack, coexistence with the non-contact wireless communication coil becomes a problem in the portable wireless terminal equipped with the above-described non-contact wireless communication function.

  Here, it is assumed that the contactless wireless communication coil and the contactless power transmission coil coexist. As a conventional example in which two coils are provided, for example, in Patent Document 1, a first coil that forms a power wave antenna and a second coil that forms a data wave antenna form a double ring. An arranged wireless card is disclosed. With this configuration, the first coil and the second coil are less likely to be covered with fingers of a hand holding the wireless card, and the reception status of both coils can be made substantially the same.

JP 2004-110854 A

  In the configuration of Patent Document 1, since the two coils are arranged in a double ring, the arrangement area of the coils is increased. In addition, simply considering a plurality of coils without considering the performance of each coil, performance degradation is expected due to electromagnetic coupling between the coils. In particular, when a plurality of coils are brought close to each other in order to reduce the size of a terminal on which the coil is mounted, performance such as power transmission efficiency and communication distance deteriorates due to electromagnetic coupling between the coils.

  The present invention has been made in view of the above circumstances, and its purpose is to suppress the performance deterioration of each coil when a plurality of coils such as a non-contact wireless communication coil and a non-contact power transmission coil coexist. However, it is to be realized in a space-saving manner.

The present invention includes a first coil, a second coil, a first magnetic body, and a second magnetic body, and in the thickness direction of the coil, the first magnetic body, the first coil, and the second magnetic body. A contactless wireless communication coil is provided in which the body and the second coil are stacked in this order and at least a part of the first coil and the second coil overlap each other.
With the above configuration, when a plurality of coils coexist, electromagnetic coupling between the coils can be reduced, and performance degradation due to electromagnetic coupling is suppressed. Further, by arranging a plurality of coils in a stacked manner, the arrangement area can be reduced, and a coil with little performance deterioration can be realized in a space-saving manner.

Further, the present invention includes the above-described coil for non-contact wireless communication, wherein the magnetic permeability of the first magnetic body is higher than the magnetic permeability of the second magnetic body.
The present invention also includes the above-described contactless wireless communication coil, wherein the resonance frequency of the first coil is lower than the resonance frequency of the second coil.
Further, the present invention includes the above-described non-contact wireless communication coil in which at least a part of the second coil is overlapped near the outer periphery of the first coil.
In addition, the present invention includes the above-described non-contact wireless communication coil in which at least a part of the second coil is located outside the first coil.
Further, the present invention includes the above-mentioned contactless wireless communication coil, wherein the first coil is for contactless power transmission and the second coil is for contactless wireless communication.

  The present invention also provides a portable wireless terminal equipped with any one of the above contactless wireless communication coils.

  According to the present invention, when a plurality of coils such as a non-contact wireless communication coil and a non-contact power transmission coil coexist, it can be realized in a space-saving manner while suppressing performance deterioration of each coil. .

The top view which shows the structure of the coil unit which concerns on the 1st Embodiment of this invention. It is sectional drawing of the coil unit of 1st Embodiment, (A) is the sectional view on the AA 'line of FIG. 1, (B) is the sectional view on the BB' line of FIG. (A), (B) is a figure which shows the magnetic field distribution of the coil unit in the position (position of FIG. 2 (A)) of the AA 'line cross section of FIG. (A), (B) is a figure which shows the magnetic field distribution of the coil unit in the position (position of FIG. 2 (B)) of the BB 'sectional view of FIG. 1 is a block diagram showing a configuration of a portable wireless terminal equipped with a coil unit of the present embodiment, a charger as an external device, and a reader / writer device. (A)-(D) are the figures which show the dimension of the coil unit of the Example which concerns on this invention. (A), (B) is a figure which shows the result of having measured the power transmission efficiency at the time of non-contact power transmission, and the maximum communication distance at the time of non-contact wireless communication as a performance of the coil unit of the Example which concerns on this invention. It is a figure which shows the structure of the coil unit which concerns on the 2nd Embodiment of this invention, FIG. 8 (A) is a top view of a coil unit, FIG.8 (B) is the sectional view on the AA 'line of FIG. 8 (A). Fig. 8 (C) is a cross-sectional view taken along line BB 'of Fig. 8 (A). It is a figure which shows the structure of the coil unit which concerns on the 3rd Embodiment of this invention, FIG. 9 (A) is a top view of a coil unit, FIG.9 (B) is the sectional view on the AA 'line of FIG. 9 (A). Fig. 9 (C) is a cross-sectional view taken along line BB 'of Fig. 9 (A). (A) and (B) are modifications in which the inner diameter and the outer shape of the first coil and the second coil are the same. (A) to (E) are modifications in which the arrangement of both coils is changed when the first coil is an elliptical ring and the second coil is a square ring. (A)-(E) are modified examples in which the arrangement of both coils is changed when the first coil is a square round ring and the second coil is a square ring. FIGS. 13A and 13B are diagrams illustrating a configuration of a coil unit of a comparative example, in which FIG. 13A is a plan view of the coil unit, and FIG. 13B is a cross-sectional view taken along line AA ′ of FIG.

  In the following embodiments, as an example of a contactless wireless communication coil and a portable wireless terminal equipped with the coil, a coil unit having a contactless wireless communication coil and a contactless power transmission coil, and the coil unit are mounted. The structural example of a portable radio | wireless terminal is shown.

(First embodiment)
FIG. 1 is a plan view showing the configuration of the coil unit according to the first embodiment of the present invention. 2 is a cross-sectional view of the coil unit according to the first embodiment. FIG. 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. It is.

  The coil unit of the present embodiment includes a first magnetic body 11, a first coil 12 that functions as a contactless power transmission coil, a second magnetic body 21, and a second coil 22 that functions as a contactless wireless communication coil. With. The first magnetic body 11 is provided corresponding to the first coil 12, and the second magnetic body 21 is provided corresponding to the second coil 22.

  The first magnetic body 11 is formed in a square plate shape, and the first coil 12 is disposed on one surface of the plate surface. The first magnetic body 11 is made of a material having a magnetic permeability higher than 1, such as ferrite. As the relative permeability μr1 of the first magnetic body 11, for example, μr1 = 200 to 2000 is used. The first coil 12 is constituted by a coil in which a conductor winding is wound in an elliptical ring shape, and receives power supplied from an external charger as a charging coil. The resonance frequency f1 of the first coil 12 is a frequency obtained by adjusting the resonance frequency of the first coil 12 using a capacitor or the like connected in parallel or in series with the first coil 12, and is, for example, about f1≈100 kHz.

  The second magnetic body 21 is formed in a square annular plate shape, and the substrate 30 on which the second coil 22 is mounted is disposed on one surface of the plate surface. The second magnetic body 21 is made of a material having a magnetic permeability higher than 1, such as ferrite. As the relative permeability μr2 of the second magnetic body 21, for example, μr2 = 10 to 300 is used. The second coil 22 is formed of a coil that is wound in a square ring shape with a conductor wiring pattern formed on a substrate 30 formed of a glass epoxy substrate or the like. The second coil 22 is a coil for non-contact wireless communication and transmits / receives data to / from an external device such as a reader / writer device. The resonance frequency f2 of the second coil 22 is a frequency obtained by adjusting the resonance frequency of the second coil 22 using a capacitor or the like connected in parallel or in series with the second coil 22, for example, about f2≈13.56 MHz. .

  A first terminal 31 for the first coil 12 and a second terminal 32 for the second coil 22 are formed at one end of the substrate 30 by a conductor wiring pattern. The first terminal 31 is connected to the first coil 12 via a wiring, and the second terminal 32 is connected to the second coil 22 by a wiring pattern of the substrate 30.

  In the coil unit of the present embodiment, the first magnetic body 11, the first coil 12, the second magnetic body 21, in the arrow H direction from the lower side of FIG. The substrate 30 and the second coil 22 are stacked in this order. When the coil unit is mounted on the portable wireless terminal, the housing is positioned further in the direction of arrow H than the second coil 22, and the coil unit is housed and provided in the housing. Therefore, when viewed from the external device side, that is, from the inner wall of the casing of the portable wireless terminal, the second coil 22, the substrate 30, the second magnetic body 21, the first coil 12, and the first magnetic body 11 are stacked in this order. . In this way, a configuration in which a plurality of magnetic bodies and a plurality of coils are laminated can suppress performance deterioration due to electromagnetic coupling between the two coils, and can secure the performance of each coil while reducing the coil layout area. Can be realized.

  At this time, the first coil 12 and the second coil 22 may be overlapped all over, but preferably have a region where at least a part thereof does not overlap. That is, it is preferable to arrange the first coil 12 and the second coil 22 in a state where at least a part of the first coil 12 and the second coil 22 overlap with each other. In the example of illustration, it arrange | positions so that a part of outer periphery of the 1st coil 12 and a part of inner periphery of the 2nd coil 22 may overlap so that it may have the area | region where both coils do not overlap. In addition, since the first coil 12 has an oval shape and the second coil 22 has a rectangular shape, the four coil portions of the second coil 22 are non-overlapping regions. Located on the outside. With such a configuration, electromagnetic coupling between both coils can be reduced.

  In the present embodiment, the relationship between the resonance frequencies of the first coil 12 and the second coil 22 is such that the resonance frequency of the first coil 12 is lower than the resonance frequency of the second coil 22 (f1 <f2). The relationship between the permeability of the first magnetic body 11 and the second magnetic body 21 is such that the permeability of the first magnetic body 11 is higher than the permeability of the second magnetic body 21 (relative permeability μr1> μr2). It is preferable to do this. By setting the characteristics of the coil and the magnetic body as described above, it is possible to more effectively reduce the performance deterioration due to the electromagnetic coupling between the two coils.

  Next, the operation during operation of the coil unit of the present embodiment will be described. 3 is a diagram showing the magnetic field distribution of the coil unit at the position of the cross section along the line AA ′ of FIG. 1 (position of FIG. 2A). FIG. 3A is a diagram when the first coil 12 is in operation. 3 (B) shows the operation time of the second coil 22, respectively. 4 is a diagram showing the magnetic field distribution of the coil unit at the position of the cross section along line BB ′ of FIG. 1 (position of FIG. 2B). FIG. 4A is a diagram when the first coil 12 is in operation. 4 (B) shows the operation time of the second coil 22, respectively.

  During operation of the first coil 12, that is, during power transmission, as shown in FIGS. 3A and 4A, the magnetic lines of force pass through the first magnetic body 11 in the vicinity of the first coil 12. A magnetic field is generated so as to enter the space. In this case, the influence of the magnetic field from the first coil 12 to the second coil 22 is small. Further, when the second coil 22 is operated, that is, during data transmission of non-contact wireless communication, as shown in FIGS. 3 (B) and 4 (B), the magnetic lines of force are generated near the second coil 22 in the second magnetic body. A magnetic field is generated so as to pass through 21 and exit into space. In this case, the influence of the magnetic field from the second coil 22 to the first coil 12 is small.

  In the present embodiment, the laminated first coil 12 and second coil 22 have non-overlapping regions, so that electromagnetic coupling between the coils is reduced. In particular, electromagnetic coupling can be made sufficiently small in the four corner regions of the coil where the coils do not overlap as shown in FIGS. 4 (A) and 4 (B).

  FIG. 5 is a block diagram showing the configuration of a portable wireless terminal equipped with the coil unit of the present embodiment, a charger as an external device, and a reader / writer device.

  The portable wireless terminal 50 includes a first coil 12 for charging and a second coil 22 for non-contact wireless communication. The first coil 12 is connected to the contactless charging unit 51, and the second coil 22 is connected to the contactless wireless communication unit 52. Here, a capacitor 54 is connected in parallel to the first coil 12, and further connected to a rectifier circuit 55 of the non-contact charging unit 51. A capacitor 56 is connected in parallel to the second coil 22, and further connected to the modulation / demodulation circuit 57 of the non-contact wireless communication unit 52. The non-contact charging unit 51 and the non-contact wireless communication unit 52 are connected to the control circuit 53, and the operation of each unit is controlled by the control circuit 53.

  The charger 60 includes a non-contact power transmission coil 63. A capacitor 64 is connected in parallel to the non-contact power transmission coil 63, and is further connected to an AC power supply circuit 61. The AC power supply circuit 61 is connected to the control circuit 62, and the output of AC power for charging is controlled by the control circuit 62.

  The reader / writer device 70 includes a non-contact wireless communication coil 73. A capacitor 74 is connected in parallel to the non-contact wireless communication coil 73 and further connected to the modulation / demodulation circuit 71. The modulation / demodulation circuit 71 is connected to the control circuit 72, and the control circuit 72 controls the data modulation and demodulation operations by non-contact wireless communication.

  In the above configuration, when charging the portable wireless terminal 50, the non-contact power transmission coil 63 of the charger 60 and the first coil 12 of the portable wireless terminal 50 are arranged close to each other and faced to each other. To the portable wireless terminal 50. At this time, the non-contact power transmission coil 63 and the first coil 12 are electromagnetically coupled, and charging power is transmitted in a non-contact manner through both coils. The resonance frequency f1 for feeding power from the non-contact power transmission coil 63 to the first coil 12 is determined by the capacitor 54 connected in parallel to the first coil 12 and the capacitor 64 connected in parallel to the non-contact power transmission coil 63. Adjusted, where f1 = 100 kHz. The AC power generated and output by the AC power supply circuit 61 is transmitted from the non-contact power transmission coil 63 to the first coil 12 and is received by the portable radio terminal 50. The transmitted AC power is rectified by the rectifier circuit 55 and converted into DC power, and the DC output is supplied to the battery unit 58 for charging. Note that it is also possible to supply a direct current output to a circuit in the portable wireless terminal 50 to serve as an operating power source for each unit.

  When performing non-contact wireless communication, the non-contact wireless communication coil 73 of the reader / writer device 70 and the second coil 22 of the portable wireless terminal 50 are arranged close to each other so as to face each other. Data is transmitted / received to / from the wireless terminal 50. At this time, the non-contact wireless communication coil 73 and the second coil 22 are electromagnetically coupled, and data transmission of non-contact wireless communication is performed via both coils. The resonance frequency f2 for communication between the non-contact wireless communication coil 73 and the second coil 22 is connected in parallel to the capacitor 56 connected in parallel to the second coil 22 and the non-contact wireless communication coil 73. Adjusted by capacitor 74, where f2 = 13.56 MHz. Data transmitted from the reader / writer device 70 to the portable wireless terminal 50 is modulated by the modulation / demodulation circuit 71, transmitted from the non-contact wireless communication coil 73 to the second coil 22, and received by the portable wireless terminal 50. The transmitted data is demodulated by the modem circuit 57 of the portable radio terminal 50. Data transmitted from the portable wireless terminal 50 to the reader / writer device 70 is modulated by the modulation / demodulation circuit 57, transmitted from the second coil 22 to the non-contact wireless communication coil 73, and received by the reader / writer device 70. The transmitted data is demodulated by the modulation / demodulation circuit 71 of the reader / writer device 70. In this way, using the contactless wireless communication function of the portable wireless terminal 50, data can be written to and read from the reader / writer device 70 to the portable wireless terminal 50 by contactless wireless communication.

  Next, the Example which measured about the performance of the coil unit of this embodiment using the actually produced evaluation sample is shown. FIG. 6 is a diagram showing dimensions of the coil unit of the embodiment. 6A shows only the first coil 12, FIG. 6B shows only the second coil 22, and FIG. 6C shows a coil unit in which the first coil 12 and the second coil 22 are stacked and combined (see FIG. 6). 1) and FIG. 6D each show a cross section of the coil unit shown in FIG.

  In the embodiment, the long side a = 48 mm, the short side b = 32 mm of the first magnetic body 11, the outer diameter c = 41 mm in the longitudinal direction of the first coil 12, the outer diameter d = 30 mm in the short direction, the second magnetic body The long side e of the 21 and the second coil 22 is 41 mm, the short side f is 31 mm, and the thickness g of the coil unit in which these are laminated is 1.5 mm. In this case, in the state where the first coil 12 and the second coil 22 are laminated, the outer peripheral dimensions of the two coils are substantially the same and overlap, and there is a region where the two coils do not overlap on the inner peripheral side. Further, since the first coil 12 is elliptical and the second coil 22 is rectangular, the four corners of the second coil 22 are regions that do not overlap.

  FIG. 7 is a diagram showing the results of measuring the power transmission efficiency during contactless power transmission and the maximum communication distance during contactless wireless communication as the performance of the coil unit of the embodiment shown in FIG. FIG. 7A shows the measurement result of the power transmission efficiency, and FIG. 7B shows the measurement result of the maximum communication distance. Here, the power transmission efficiency is not the transmission efficiency of only the coil, but the efficiency of the entire charging system including the AC power supply circuit of the charger as shown in FIG. 5 to the DC output of the portable wireless terminal.

  In the state of the first coil 12 alone shown in FIG. 6A, the power transmission efficiency was 40.3 [%]. In the state where the first coil 12 and the second coil 22 shown in FIG. 6C coexist, the power transmission efficiency was 40.4 [%]. In this case, two coils are stacked and coexisted, and even if the second coil 22 is disposed on the external device side of the first coil 12, performance degradation due to electromagnetic coupling does not occur in non-contact power transmission. .

In the state of the second coil 22 alone shown in FIG. 6B, the maximum communication distance was 126 [mm], and the insensitive area (Null area) did not occur. Further, in the state where the first coil 12 and the second coil 22 shown in FIG. 6C coexist, the maximum communication distance is 127 [mm], and no dead area (Null area) is generated. In this case, two coils are stacked and coexisted, and even if the first coil 12 is disposed in the vicinity of the second coil 22, performance degradation due to electromagnetic coupling does not occur in non-contact wireless communication.
In addition, in the state which removed the 2nd magnetic body 21 from the state of FIG.6 (C), it has confirmed that the maximum communication distance deteriorates to 120 [mm] by the electromagnetic coupling between coils, By providing the corresponding second magnetic body 21 between the first coil and the first coil, generation of electromagnetic coupling can be suppressed in non-contact wireless communication, and the maximum communication distance can be improved.

  Thus, according to the present embodiment, when a plurality of coils of the first coil 12 and the second coil 22 coexist, electromagnetic coupling between the coils can be reduced, and performance degradation due to electromagnetic coupling can be suppressed. Further, by arranging a plurality of coils in a stacked manner, the arrangement area can be reduced, and a coil with little performance deterioration can be realized in a space-saving manner. For this reason, in the portable wireless terminal equipped with the coil unit including the coil for contactless wireless communication according to the present embodiment, it is possible to suppress performance degradation during both contactless power transmission and contactless wireless communication while achieving downsizing. The desired performance can be obtained with a space-saving coil unit.

(Second Embodiment)
8A and 8B are diagrams showing the configuration of the coil unit according to the second embodiment of the present invention. FIG. 8A is a plan view of the coil unit, and FIG. 8B is AA in FIG. FIG. 8C is a cross-sectional view taken along the line BB ′ of FIG. 8A. In addition, the same code | symbol is attached | subjected about the component similar to 1st Embodiment shown in FIG.1 and FIG.2, and description is abbreviate | omitted.

  The second embodiment is an example in which the shape of the first coil in the first embodiment is changed. 11 A of 1st magnetic bodies are formed in the square plate shape similarly to 1st Embodiment. The first coil 12 </ b> A is configured by a coil in which a conductor winding is wound in an annular shape with a square round shape. The second magnetic body 21A and the second coil 22A have substantially the same configuration as that of the first embodiment. That is, the second magnetic body 21A is formed in a square annular plate shape, and the second coil 22A is wound in a square annular shape by a conductor wiring pattern formed on a substrate 30A such as a glass epoxy substrate. Consists of coils.

  As in the first embodiment, the first magnetic body 11A and the first magnetic body 11A are arranged in the arrow H direction from the lower side in the coil thickness direction (vertical direction in FIGS. 8B and 8C). The coil 12A, the second magnetic body 21A, the substrate 30A, and the second coil 22A are stacked in this order. When viewed from the external device side, that is, from the inner wall of the casing of the portable wireless terminal, the second coil 22A, the substrate 30A, the second magnetic body 21A, the first coil 12A, and the first magnetic body 11A are stacked in this order.

  The first coil 12A and the second coil 22A are arranged in a state in which at least a part of the first coil 12A and the second coil 22A are overlapped so as to have a region that does not overlap the part. At this time, it arrange | positions so that the outer side of 1st coil 12A and 2nd coil 22A may overlap so that it may have the area | region where both coils do not overlap on the inner peripheral side of a coil. Further, since the first coil 12A has a square round shape and the second coil 22A has a square shape, the four corners of the second coil 22A are regions that do not overlap.

  With such a configuration, similarly to the first embodiment, even when two coils are stacked and coexisted, the electromagnetic coupling between both coils can be reduced, and performance degradation due to the electromagnetic coupling can be suppressed. In addition, the two coils can be stacked and arranged to reduce the size.

(Third embodiment)
9A and 9B are diagrams showing the configuration of a coil unit according to the third embodiment of the present invention. FIG. 9A is a plan view of the coil unit, and FIG. 9B is an AA view of FIG. 9A. FIG. 9C is a sectional view taken along the line BB ′ of FIG. 9A. In addition, the same code | symbol is attached | subjected about the component similar to 1st Embodiment shown in FIG.1 and FIG.2, and description is abbreviate | omitted.

  The third embodiment is an example in which the shape of the second coil in the first embodiment is changed. The first magnetic body 11B and the first coil 12B have substantially the same configuration as in the first embodiment. That is, the first magnetic body 11B is formed in a rectangular plate shape, and the first coil 12B is configured by a coil formed by winding a conductor winding in an elliptical ring shape. The second magnetic body 21B is formed in an elliptical annular plate shape, and the second coil 22B is a coil that is wound in an elliptical shape by a conductor wiring pattern formed on a substrate 30B such as a glass epoxy substrate. Composed.

  Similarly to the first embodiment, the first magnetic body 11B and the first magnetic body 11B are arranged in the arrow H direction from the lower side in the coil thickness direction (vertical direction in FIGS. 9B and 9C). The coil 12B, the second magnetic body 21B, the substrate 30B, and the second coil 22B are stacked in this order. When viewed from the external device side, that is, from the inner wall of the casing of the portable wireless terminal, the second coil 22B, the substrate 30B, the second magnetic body 21B, the first coil 12B, and the first magnetic body 11B are stacked in this order.

  The first coil 12B and the second coil 22B are arranged in a state in which at least a part of the first coil 12B and the second coil 22B overlap so as to have a region that does not overlap the part. At this time, it arrange | positions so that the outer side of the 1st coil 12B and the 2nd coil 22B may overlap so that it may have the area | region where both coils do not overlap on the inner peripheral side of a coil. That is, at least a part of the first coil 12B and the second coil 22B overlap each other near the outer periphery of the first coil 12B.

  With such a configuration, similarly to the first embodiment, even when two coils are stacked and coexisted, the electromagnetic coupling between both coils can be reduced, and performance degradation due to the electromagnetic coupling can be suppressed. In addition, the two coils can be stacked and arranged to reduce the size.

(Modification)
Below, some modifications which changed arrangement of the 1st coil and the 2nd coil are shown.

  FIG. 10 shows an example in which the inner diameter and the outer shape of the first coil and the second coil are the same. In the example of FIG. 10A, an elliptical annular first coil 12C and a square annular second coil 22C are stacked. In the example of FIG. 10B, a rectangular first round coil 12D and a rectangular second coil 22D are stacked and arranged.

  In this case, the first coil and the second coil are almost completely overlapped. However, as shown in FIG. 2, by providing a second magnetic body corresponding to the second coil between the first coil and the second coil. , Performance degradation due to electromagnetic coupling can be reduced.

  FIG. 11 shows an example in which the arrangement of both coils is changed when the first coil is an elliptical ring and the second coil is a square ring as in FIG. In the example of FIG. 11A, an elliptical annular first coil 12E and a rectangular annular second coil 22E are arranged so as to overlap each other on the outer peripheral sides of both sides in the coil longitudinal direction. In the example of FIG. 11B, an elliptical annular first coil 12F and a rectangular annular second coil 22F are arranged so as to overlap each other on the outer peripheral side of both sides in the coil lateral direction.

  In the example of FIG. 11C, an elliptical annular first coil 12G and a rectangular annular second coil 22G are arranged on the outer peripheral side of two adjacent sides. In the example of FIG. 11D, an elliptical annular first coil 12H and a rectangular annular second coil 22H are arranged on the outer peripheral side of one side. In the example of FIG. 11E, an elliptical annular first coil 12I and a rectangular annular second coil 22I are arranged on the outer peripheral side of three sides.

In this case as well, as in the first embodiment, a part of the outer periphery of the first coil overlaps with the second coil, but the second magnetic body corresponding to the second coil as shown in FIG. By providing between the first coil and the first coil, performance degradation due to electromagnetic coupling can be reduced.
In addition, the more the sides where the first coil and the second coil do not overlap, the larger the arrangement area of the entire coil, while the characteristic deterioration due to electromagnetic coupling between the coils can be further reduced.

  FIG. 12 shows an example in which the arrangement of the two coils is changed when the first coil is formed in a square rounded annular shape and the second coil is formed in a rectangular annular shape as in FIG. In the example of FIG. 12A, a square-rounded annular first coil 12J and a rectangular-annular second coil 22J are arranged so as to overlap each other on the outer peripheral sides of both ends in the coil longitudinal direction. In the example of FIG. 12B, a square-rounded annular first coil 12K and a square-annular second coil 22K are arranged so as to overlap each other on the outer peripheral sides of both ends in the coil lateral direction.

  In the example of FIG. 12C, a square-shaped rounded first coil 12L and a square-shaped second coil 22L are arranged so as to overlap each other on the outer peripheral side of two adjacent sides. In the example of FIG. 12D, an annular first coil 12M having a rounded rectangular shape and a square annular second coil 22M are arranged so as to overlap each other on the outer peripheral side of one side. In the example of FIG. 12 (E), a rectangular square-round annular first coil 12N and a rectangular annular second coil 22N are arranged on the outer peripheral side of three sides.

Also in this case, as in the first and second embodiments, a part of the outer periphery of the first coil overlaps the second coil, but corresponds to the second coil as shown in FIGS. By providing the second magnetic body to be interposed between the first coil and the first coil, it is possible to reduce performance deterioration due to electromagnetic coupling.
In addition, the more the sides where the first coil and the second coil do not overlap, the larger the arrangement area of the entire coil, while the characteristic deterioration due to electromagnetic coupling between the coils can be further reduced.

(Comparative example)
13A and 13B are diagrams showing a configuration of a coil unit according to a comparative example. FIG. 13A is a plan view of the coil unit, and FIG. 13B is a cross-sectional view taken along line AA ′ of FIG.

  The coil unit of the comparative example includes a first magnetic body 511, a first coil 512 that functions as a contactless power transmission coil, and a second coil 522 that functions as a contactless wireless communication coil.

  The first magnetic body 511 is formed in a rectangular plate shape, and the first coil 512 and the second coil 522 are disposed on one surface of the plate surface. The first coil 512 is constituted by a coil in which a conductor winding is wound in an elliptical ring shape, and receives power supplied from an external charger as a charging coil. The second coil 522 is formed of a coil that is wound in an elliptical ring shape by a conductor wiring pattern formed on a substrate 530 formed of a glass epoxy substrate or the like. The second coil 522 is a coil for non-contact wireless communication and transmits / receives data to / from an external device such as a reader / writer device. The second coil 522 is disposed on the outer peripheral side of the first coil 512, and the first coil 512 and the second coil 522 are positioned on substantially the same plane without overlapping.

  At one end of the substrate 530, a first terminal 531 for the first coil 512 and a second terminal 532 for the second coil 522 are formed by a conductor wiring pattern. The first terminal 531 is connected to the first coil 512 through wiring, and the second terminal 532 is connected to the second coil 522 through a wiring pattern of the substrate 530.

  In this comparative example, the first coil 512 and the second coil 522 are arranged without being stacked, and the second magnetic body is not provided. Therefore, the first coil 512 and the second coil 522 When close to each other, the electromagnetic coupling between both coils increases, and the performance is deteriorated due to the influence. For example, it has been confirmed that the maximum communication distance of non-contact wireless communication is deteriorated to 117 [mm]. It is difficult to improve the maximum communication distance of non-contact wireless communication using the coil unit. In addition, by arranging the second coil 522 outside the first coil 512 and arranging the two coils so as not to overlap, the arrangement area of the coil increases, and the radio communication terminal mounting the coil unit becomes large. Become.

  On the other hand, in embodiment which concerns on this invention, when a some coil is made to coexist with the structure mentioned above, both size reduction of a structure and suppression of the performance deterioration of each coil can be made compatible.

  The present invention is intended to be variously modified and applied by those skilled in the art based on the description in the specification and well-known techniques without departing from the spirit and scope of the present invention. Included in the scope for protection. In addition, the constituent elements in the above-described embodiment may be arbitrarily combined without departing from the spirit of the invention.

  The present invention has an effect that when a plurality of coils such as a non-contact wireless communication coil and a non-contact power transmission coil coexist, it can be realized in a space-saving manner while suppressing performance deterioration of each coil. For example, it is useful as a non-contact wireless communication coil capable of non-contact wireless communication such as a mobile phone terminal and a smartphone, and a mobile wireless terminal equipped with the coil.

11, 11A, 11B 1st magnetic body 12, 12A-12N 1st coil 21, 21A, 21B 2nd magnetic body 22, 22A-22N 2nd coil 30, 30A, 30B Board | substrate 31 1st terminal 32 2nd terminal 50 Carrying Wireless terminal 51 Non-contact charging unit 52 Non-contact wireless communication unit 53 Control circuit 55 Rectifier circuit 57 Modulation / demodulation circuit 58 Battery 60 Charger 61 AC power supply circuit 62 Control circuit 63 Coil for non-contact power transmission 70 Reader / writer device 71 Modulation / demodulation circuit 72 Control circuit 73 Non-contact wireless communication coil

Claims (7)

A first coil;
A second coil;
A first magnetic body;
A second magnetic body,
In the thickness direction of the coil,
The first magnetic body, the first coil, the second magnetic body, and the second coil are stacked in this order,
A coil for non-contact wireless communication in which at least a part of the first coil and the second coil overlap each other. The coil for contactless wireless communication according to claim 1,
The coil for non-contact radio | wireless communication whose magnetic permeability of a said 1st magnetic body is higher than the magnetic permeability of a said 2nd magnetic body. The coil for contactless wireless communication according to claim 1 or 2,
The non-contact wireless communication coil, wherein the resonance frequency of the first coil is lower than the resonance frequency of the second coil. The contactless wireless communication coil according to any one of claims 1 to 3,
A coil for non-contact wireless communication in which at least a part of the second coil overlaps near the outer periphery of the first coil. The contactless wireless communication coil according to any one of claims 1 to 4,
A coil for non-contact wireless communication, wherein at least a part of the second coil is located outside the first coil. The contactless wireless communication coil according to any one of claims 1 to 5,
The contactless wireless communication coil, wherein the first coil is for contactless power transmission and the second coil is for contactless wireless communication.   A portable wireless terminal equipped with the non-contact wireless communication coil according to any one of claims 1 to 6.

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