Coil arrays, short-range wireless communication devices, resonator modules, and wireless power transfer devices

Abstract

The present invention provides a coil array, a short-range wireless communication device, a resonator module, and a wireless power supply device that establish a good resonant frequency whether the coils are connected or separated. [Solution] The coil array comprises a first support 13a that supports a first coil 14, a second support 13b that supports a second coil 14, a structure 16 formed on the first support 13a that detachably connects the second support 13b to the first support 13a and positions the second coil 14 on the first coil 14, a first compensation element 24 supported by the first support 13a at a position separated from the first coil 14 and coupling a predetermined impedance to the positioned second coil 14, and a second compensation element supported by the second support 13b at a position separated from the second coil 14 and coupling a predetermined impedance to the first coil 14.

Description

Technical Field

[0001] The present invention relates to a coil array including a plurality of coils, a short-range wireless communication device, a resonator module, and a wireless power supply device.

Background Art

[0002] Patent Document 1 discloses a coil array including a plurality of coils arranged in a determined layout. A compensation element having reactance is connected to each individual coil. The influence of cross-coupling is canceled by the reactance of the compensation element. The resonance frequency is maintained at a determined frequency. Two adjacent coils function as one resonator.

Prior Art Documents

Patent Documents

[0003]

Patent Document 1

Non-Patent Documents

[0004]

Non-Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0005] When the coils are disconnected, the cross-coupling between them is eliminated, while the reactance of the compensating element remains connected. The impedance of each individual coil fluctuates significantly. The resonant frequency shifts considerably. In particular, in Patent Document 1, the reactance of the compensating element is calculated according to conditions such as how many coils are connected and the relative positions of those coils. The reactance of the compensating element must be calculated for each individual coil. Moreover, if the conditions change, the reactance of the compensating element must be recalculated.

[0006] The present invention aims to provide a coil array, a short-range wireless communication device, a resonator module, and a wireless power supply device that can establish a good resonant frequency whether the coils are connected or separated. [Means for solving the problem]

[0007] A coil array according to one embodiment of the present invention comprises: a first support for supporting a first coil; a second support for supporting a second coil; a structure formed on the first support for detachably connecting the second support to the first support and positioning the second coil relative to the first coil; a first compensation element supported on the first support at a position separated from the first coil and coupling a predetermined impedance to the positioned second coil; and a second compensation element supported on the second support at a position separated from the second coil and coupling a predetermined impedance to the first coil.

[0008] Another embodiment of the present invention provides a short-range wireless communication device comprising the above-mentioned coil array.

[0009] A resonator module according to another embodiment of the present invention comprises: a first support for supporting a first coil; a structure formed on the first support for detachably connecting a second support to the first support and for positioning a second coil supported by the second support to the first coil; and a compensation element supported by the first support for coupling a predetermined impedance to the positioned second coil.

[0010] Another embodiment of the present invention provides a wireless power supply device comprising: a first support that supports a first coil so as to be magnetically coupled to a power receiving coil; a second support that supports a second coil so as to be magnetically coupled to a power receiving coil; a structure formed on the first support that detachably connects the second support to the first support and positions the second coil relative to the first coil; a first compensation element supported on the first support at a position separated from the first coil and coupling a predetermined impedance to the positioned second coil; and a second compensation element supported on the second support at a position separated from the second coil and coupling a predetermined impedance to the first coil. [Effects of the Invention]

[0011] As described above, according to the embodiments of the present invention, a coil array, a short-range wireless communication device, a resonator module, and a wireless power supply device are provided that can establish a good resonant frequency whether the coils are connected or separated. [Brief explanation of the drawing]

[0012] [Figure 1] This is a conceptual diagram illustrating the configuration of a coil array according to an embodiment of the present invention. [Figure 2] This is a schematic diagram illustrating the general structure of individual resonator modules. [Figure 3] This is a schematic diagram illustrating the operation of a resonator module. [Figure 4] This graph shows the layout of the resonator module and its frequency characteristics. [Figure 5] This graph shows the layout of the resonator module and its frequency characteristics. [Figure 6] This graph shows the layout of a resonator module related to a comparative example and its frequency characteristics. [Figure 7] This is a conceptual diagram illustrating the configuration of a wireless power supply device according to an embodiment of the present invention. [Figure 8]It is a conceptual diagram schematically showing the configuration of a wireless power feeding device according to another embodiment. [Figure 9] It is a conceptual diagram showing a first modification of the structure. [Figure 10] It is a conceptual diagram showing a second modification of the structure. [Figure 11] It is a conceptual diagram showing a third modification of the structure. [Figure 12] It is a conceptual diagram showing a fourth modification of the structure. [Figure 13] It is a conceptual diagram showing a fifth modification of the structure.

Embodiments for Carrying Out the Invention

[0013] Hereinafter, an embodiment of the present invention will be described while referring to the accompanying drawings.

[0014] FIG. 1 schematically shows a coil array 11 according to an embodiment of the present invention. The coil array 11 includes a plurality of resonator modules 12. Each of the resonator modules 12 has a common structure. One form of the resonator modules 12 is combined to establish one coil array 11. Such a coil array 11 may be used in a wireless power feeding device or a short-range wireless communication device as will be described later.

[0015] Each individual resonator module 12 includes a housing (support) 13. Here, the contour of the housing 13 is set to a regular hexagon. Alternatively, the contour of the housing 13 may be formed into a hexagon in which two opposing sides are longer than the other sides, may be formed into a quadrilateral such as a square, a rectangle, or a rhombus, or may be formed into a triangle such as an equilateral triangle or a right isosceles triangle.

[0016] As shown in FIG. 2, one coil 14 is supported by one housing 13. The coil 14 may be a spiral coil or a planar coil. The contour of the housing 13 is positioned on the axis 15 of the coil 14. The central axis of the contour overlaps with the axis 15 of the coil 14.

[0017] Another housing 13 (hereinafter referred to as "second housing 13b") is connected to housing 13 (hereinafter referred to as "first housing 13a"). In each housing 13, a structure 16 is formed on each side of the contour that connects housing 13 to housing 13. The structure 16 of another housing 13 is always connected to the structure 16 in a predetermined positional relationship. The structure 16 guides the connection of the housings 13 to each other. When the housings 13 are connected to each other, the structure 16 positions the other coil 14 relative to the coil 14. One housing 13 is connected to one structure 16.

[0018] Each structure 16 comprises a first connector 18 connected to a coil 14 on a housing 13, and a second connector 19 separated from the coil 14 on the housing 13. The first connector 18 and the second connector 19 are arranged symmetrically with respect to the bisector 21 of one side of the contour. When the housings 13 are joined together, the second connector 19 of the second housing 13b is joined to the first connector 18 of the first housing 13a. Similarly, the first connector 18 of the second housing 13b is joined to the second connector 19 of the first housing 13a. The first connector 18 and the second connector 19 are formed in such a structure that they can be joined and separated not only in a direction of movement parallel to the bisector 21, but also in a direction of movement that intersects the bisector 21 at a predetermined angle. The connection between the structures 16 is maintained, for example, by the action of magnetism.

[0019] The first connector 18 is electrically connected to the coil 14 by a conductive wire 22. The second connector 19 is electrically connected to the compensating element 24 by a conductive wire 23. When the first connector 18 and the second connector 19 are coupled, the conductive wire 22 on the first connector 18 side and the conductive wire 23 on the second connector 19 side are mechanically connected by a conductor. On one housing 13, the compensating element 24 is supported by the housing 13 in a position separated from the coil 14. The compensating element 24 couples a predetermined impedance to the coil 14 in the other housing 13, which is positioned by the action of the structure 16.

[0020] Next, the operation of the coil array 11 will be described. When the second housing 13b is connected to the first housing 13a, the coil 14 in the first housing 13a (hereinafter referred to as "first coil 14a") and the coil 14 in the second housing 13b (hereinafter referred to as "second coil 14b") are arranged in a predetermined positional relationship. Because a specific positional relationship is established, the second coil 14b affects the impedance of the first coil 14a as designed. Similarly, the first coil 14a affects the impedance of the second coil 14b as designed.

[0021] The first connector 18 of the first housing 13a is connected to the second connector 19 of the second housing 13b. As a result, as shown in Figure 3, the first coil 14a is connected to the compensation element 24 in the second housing 13b (hereinafter referred to as "second compensation element 24b"). When the first coil 14a is alone, its impedance is compensated by the impedance Z1 of the capacitor. When the effect of cross-coupling from the second coil 14b acts on the impedance of the first coil 14a, the impedance of the first coil 14a is compensated by the impedance Z1 and the impedance Z2 of the second compensation element 24b. The effects of cross-coupling cancel each other out. Since a specific positional relationship is established between the first coil 14a and the second coil 14b, the impedance Z2 of the second compensation element 24b is set to a fixed value in advance.

[0022] Similarly, the second connector 19 of the first housing 13a is coupled to the first connector 18 of the second housing 13b. As a result, the compensation element 24 (hereinafter referred to as "first compensation element 24a") in the first housing 13a is connected to the second coil 14b. When the second coil 14b is used alone, its impedance is compensated by the impedance Z1 of the capacitor. When the effect of cross-coupling from the first coil 14a acts on the impedance of the second coil 14b, the impedance of the second coil 14b is compensated by the impedance Z1 and the impedance Z2 of the first compensation element 24a. The effects of cross-coupling cancel each other out. Since a specific positional relationship is established between the first coil 14a and the second coil 14b, the impedance Z2 of the first compensation element 24a is set to a fixed value in advance. In this way, a good single resonant frequency is established with the two coils 14a and 14b. The two coils 14a and 14b function as a single resonator.

[0023] When the second housing 13b is separated from the first housing 13a, the first coil 14a is disconnected from both the cross-coupling and the second compensating element 24b. Impedance fluctuations are avoided in the first coil. The first coil 14a can be used as a resonator on its own. Similarly, the second coil 14b is disconnected from both the cross-coupling and the first compensating element 24a. The second coil 14b can be used as a resonator on its own. Whether the first coil 14a and the second coil 14b are connected to each other or separated, a good resonant frequency is established. In other words, each resonator module 12 eliminates the effect of cross-coupling on its connected partner with its own capacitor and compensating element 24 connected to the connected partner.

[0024] Multiple (two or more) second housings 13b are connected to the first housing 13a. The second coils 14b are arranged in a predetermined positional relationship for each structure 16 in the first coil 14a. A second compensating element 24b is connected to each individual second coil 14b in the first coil 14a. Although the impedance of the first coil 14a is affected by the cross-coupling effect of each individual second coil 14b, the impedance of the first coil 14a is adjusted by the action of each second compensating element 24b. The effect of cross-coupling is canceled out by the second compensating element 24b. No matter how many second housings 13b are connected to the first housing 13a, the first coil 14a and the second coils 14b function as a single resonator. Similarly, although each individual second coil 14b is affected by the cross-coupling effect from the first coil 14a, the impedance of the second coil 14b is adjusted by the action of each first compensating element 24a. The effect of cross-coupling is canceled out by the first compensating element 24a. In this way, a single resonant frequency is successfully established using multiple coils 14a and 14b. The coil array 11 functions as a single resonator.

[0025] In this embodiment, the housing 13 has a regular hexagonal contour. Structures 16 are arranged along each side of the contour. The housings 13 are connected along each side of the contour. Since all housings 13 have the same contour, they are laid out on one surface. Since all resonator modules 12 are configured in the same form, the coil array 11 functions as a single resonator regardless of the layout in which the housings 13 are connected.

[0026] The inventors verified the operation of the coil array 11. For verification, the inventors fabricated resonator modules 12. Each resonator module 12 was supplied with power based on electromagnetic induction. The frequency characteristics of the coil array 11 were measured. As shown in Figure 4, it was confirmed that a single resonant frequency could be successfully established with combinations of two, three, four, or five resonator modules 12. In all combinations, the resonant frequency of one resonator module 12 was maintained, or the shift in the resonant frequency was minimized. As shown in Figure 5, it was confirmed that a single resonant frequency could be successfully established regardless of how the five resonator modules 12 were laid out.

[0027] For verification, the inventors prepared a resonator module according to a comparative example. In the comparative example, the compensation element 24 was omitted. Each resonator module incorporated a coil 14 similar to that of the resonator module 12 in this embodiment. In the comparative example, the effect of cross-coupling was observed directly. As shown in Figure 6, it was confirmed that the resonant frequency shifted significantly as the number of resonator modules increased to two, three, four, and five. Furthermore, it was confirmed that when the layout of the five resonator modules was changed, the resonant frequency shifted or multiple resonant frequencies appeared.

[0028] Figure 7 schematically shows the overall configuration of a wireless power supply device 31 according to an embodiment of the present invention. The wireless power supply device 31 includes a power supply 32 connected to at least one of a plurality of resonator modules 12. Here, the power supply 32 is connected to one resonator module 12 (12a). The power supply 32 supplies power to the coil 14 of the resonator module 12a. The resonator modules 12, 12a function as a single resonator. When a power receiver is placed on the surface of each resonator module 12, 12a, power is supplied to the power receiver by electromagnetic induction. In this way, the power receiver is powered. The power supply 32 may be individually connected to two or more resonator modules 12, 12a.

[0029] Figure 8 schematically shows the overall configuration of a wireless power supply device 41 according to another embodiment. The wireless power supply device 41 includes a transmitter 42 coupled to a plurality of resonator modules 12 by electromagnetic induction. The transmitter 42 is formed, for example, from an electromagnetic coil. Each resonator module 12 functions as a single resonator. When a receiver is placed on the surface of each resonator module 12, power is supplied to the receiver by electromagnetic induction. In this way, the receiver is powered. Each resonator module 12 also functions as a receiver.

[0030] As shown in Figure 9, in the structure 16, when coupling the first connector 18 and the second connector 19, the conductive wire 22 on the first connector 18 side and the conductive wire 23 on the second connector 19 side may be connected by a magnetic field. Depending on the magnetic field coupling, the second compensating element 24b is connected to the first coil 14a. The second compensating element 24b couples a predetermined impedance to the first coil 14a. Depending on the magnetic field coupling, the first compensating element 24a is connected to the second coil 14b. The first compensating element 24a couples a predetermined impedance to the second coil 14b.

[0031] As shown in Figure 10, in the structure 16, when coupling the first connector 18 and the second connector 19, the conductive wire 22 on the first connector 18 side and the conductive wire 23 on the second connector 19 side may be connected by an electric field. Depending on the electric field coupling, the second compensating element 24b is connected to the first coil 14a. The second compensating element 24b couples a predetermined impedance to the first coil 14a. Depending on the electric field coupling, the first compensating element 24a is connected to the second coil 14b. The first compensating element 24a couples a predetermined impedance to the second coil 14b.

[0032] As shown in Figure 11, whether the compensating element 24 is connected to the coil 14 in accordance with magnetic field coupling or in accordance with electric field coupling, the impedance Z2 of the compensating element 24 is the impedance matrix Z mIt should be adjusted based on the impedance matrix Z. Structure 16 positions coil 14 supported by other housings 13 in relation to coil 14 supported by its own housing 13, m This is set in advance.

[0033] As shown in Figure 12, each resonator module 12 may incorporate a first switch 51 for switching the energization of the coil 14 on and off, and a second switch 52 for switching the energization of the compensation element 24 on and off. The second switch 52 is linked to the first switch 51. That is, in one resonator module 12, when energization is established in the coil 14, energization is also established in the compensation element 24. As described above, each resonator module 12 eliminates the effect of cross-coupling on its connected partner with its own compensation element 24 connected to the partner. When the energization of the coil 14 in one resonator module 12 is cut off, the energization of the compensation element 24 is also cut off. The effect of cross-coupling on the connected partner disappears, and the impedance of the compensation element 24 also disappears. One of the coils 14 is deactivated while the connection between the two housings 13 is maintained.

[0034] As shown in Figure 13, two resonator modules 12 (12c, 12d) are arranged diagonally, and a compensation element 24 is connected to the coil 14. The two resonator modules 12c and 12d are abutted against each other at the corners of the polygonal contour. Here, the first housing 13c of resonator module 12c and the second housing 13d of resonator module 12d are commonly connected to the third housing 13z of resonator module 12z. The third housing 13z has a first structure 54 that is detachably connected to the structure 16 of the first housing 13c and positions the third coil 14z on the first coil 14c, and a second structure 55 that is detachably connected to the structure 16 of the second housing 13d and positions the third coil 14z on the second coil 14d. The first structure 54 and the second structure 55 each include a third connector 56 connected to the first connector 18 of structure 16 and a fourth connector 57 connected to the second connector 19 of structure 16. In the third housing 13z, the third connector 56 and the fourth connector 57 are simply connected by a wire 58. The wire 58 functions as a relay wire connecting the first connector 18 of the first housing 13c to the second connector 19 of the second housing 13d, and as a relay wire connecting the second connector 19 of the first housing 13c to the first connector 18 of the second housing 13d. Thus, the coil 14c of the first housing 13c is connected to the compensation element 24 of the second housing 13d. The coil 14d of the second housing 13d is connected to the compensation element 24 of the first housing. [Explanation of Symbols]

[0035] 11 Coil Array 12 Resonator Modules 12a Resonator Module 13 Support (Housing) 13a Support (First Housing) 13b Support (Second Housing) 14 coils 14a Coil (First Coil) 14b Coil (2nd coil) 16 Structure 24 Compensation elements 24a Compensation element (first compensation element) 24b Compensation element (second compensation element) 31 Wireless power supply device 32 Power supply 41 Wireless power supply device 42 Power Transmitters 51 First switch 52 Second switch

Claims

1. A first support that supports the first coil, A second support that supports the second coil, A structure formed on the first support, which detachably connects the second support to the first support and positions the second coil on the first coil, A first compensation element is supported by the first support at a position separated from the first coil and couples a predetermined impedance to the positioned second coil, A second compensating element, supported by the second support at a position separated from the second coil, and coupled to the first coil with a predetermined impedance, A coil array comprising the above.

2. The first support has a plurality of structures formed thereon, each supporting the second support, and the first compensation element, which is combined with each structure, is mounted on it. The coil array according to claim 1.

3. The first support has a hexagonal, quadrilateral, or triangular outline, and the structure is positioned on each side of the outline. The coil array according to claim 2.

4. The second support has the same contour as the first support. The coil array according to claim 3.

5. A first switch connected to at least one of the first coil and the second coil, which turns the energization of the first coil and the second coil on and off, The system further comprises a second switch connected to at least one of the first and second compensating elements, which switches the power supply to the first and second compensating elements on and off. The coil array according to claim 1.

6. A short-range wireless communication device comprising the coil array described in claim 1.

7. A first support that supports the first coil, A structure formed on the first support, which detachably connects the second support to the first support, and positions the second coil supported by the second support on the first coil, A compensation element that is supported by the first support and positioned to couple a predetermined impedance to the second coil, A resonator module equipped with a resonator module.

8. The first support has a plurality of structures formed thereon, each supporting the second support, and the first compensation element, which is combined with each structure, is mounted on it. The resonator module according to claim 7.

9. The first support has a hexagonal, quadrilateral, or triangular outline, and the structure is positioned on each side of the outline. The resonator module according to claim 8.

10. A first switch connected to the first coil for turning the power to the first coil on and off, The system further comprises a second switch connected to the compensation element for turning the power to the compensation element on and off. The resonator module according to claim 7.

11. A first support that supports the first coil so as to be magnetically coupled to the power receiving coil, A second support that supports a second coil so as to be magnetically coupled to the power receiving coil, A structure formed on the first support, which detachably connects the second support to the first support and positions the second coil on the first coil, A first compensation element is supported by the first support at a position separated from the first coil and couples a predetermined impedance to the positioned second coil, A second compensating element, supported by the second support at a position separated from the second coil, and coupled to the first coil with a predetermined impedance, A wireless power supply device equipped with the following features.

12. The system comprises at least one power supply connected to at least one of the first coil and the second coil, which supplies power to the connected first coil and the second coil. The wireless power supply device according to claim 11.

13. The system includes a transmitter coupled to the first coil and the second coil by electromagnetic induction. The wireless power supply device according to claim 11.

14. A first switch connected to at least one of the first coil and the second coil, which turns the energization of the first coil and the second coil on and off, The system further comprises a second switch connected to at least one of the first and second compensating elements, which switches the power supply to the first and second compensating elements on and off. The wireless power supply device according to claim 11.

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