Wireless charging type power supply device

Abstract

To expand a power receiving range of a wireless charging type power supply device.SOLUTION: The wireless charging type power supply device includes a housing, a substrate 62 housed in the housing, a power storage device, and a power receiving antenna. The substrate 62 has a first main surface 62a and a second main surface 62a opposite to the first main surface 62b. A power reception circuit that charges power storage device 16 with power received by the power reception antenna is mounted on substrate 62. The power receiving antenna includes a first antenna 70 located on the first main surface 62a side of the substrate 62 and a second antenna 72 located on the second main surface 62b side of the substrate 62. The first antenna 70 and the second antenna 72 are dipole antennas. The direction D1 in which the element Em of the first antenna 70 extends coincides with the direction D2 in which the element Em of the second antenna 72 extends.SELECTED DRAWING: Figure 6

Description

[Technical Field]

[0001] The present invention relates to a wireless charging type power supply device. [Background technology]

[0002] Patent Document 1 describes an AA-type wireless rechargeable battery device. This device includes one or more antennas that rotate together with a flexible circuit board inside, and a spatial controller that automatically rotates the flexible circuit board (paragraphs "0065" to "0067"). This device aims to optimally position the antennas by rotating the flexible circuit board using the spatial controller. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] Patent No. 6725531 Summary of the Invention [Problem to be solved by the invention]

[0004] A wireless charging type power supply device is required to have an expanded power receiving range in order to efficiently charge a power storage device provided inside the wireless charging type power supply device. [Means for solving the problem]

[0005] The following describes an embodiment for solving the above problem. [Embodiment 1] A wirelessly rechargeable power supply device comprising a housing, a substrate housed within the housing, a power storage device, and a power receiving antenna, wherein the substrate has a first main surface and a second main surface opposite the first main surface, the substrate is equipped with a power receiving circuit that charges the power storage device with power received by the power receiving antenna, the power receiving antenna includes a first antenna located on the first main surface side of the substrate and a second antenna located on the second main surface side of the substrate, the first antenna and the second antenna are dipole antennas, and the direction in which the elements of the first antenna extend is the same as the direction in which the elements of the second antenna extend.

[0006] According to the above configuration, the first antenna is a dipole antenna having directivity in the direction in which the first main surface of the substrate faces, and the second antenna is a dipole antenna having directivity in the direction in which the second main surface of the substrate faces. By providing two dipole antennas with opposite directivities as described above, it is possible to expand the power receiving range in a specific direction, i.e., in the direction in which the first main surface of the substrate faces and the direction in which the second main surface faces.

[0007] [Aspect 2] The wireless charging-type power supply device according to Aspect 1, wherein the first antenna and the second antenna are positioned at positions spaced apart by an angle of 165 degrees or more and 180 degrees or less in a circumferential direction around the substrate in a side view seen from the direction in which the element of the first antenna extends. This configuration more significantly achieves the effect of expanding the power receiving range in the direction in which the first main surface and the second main surface of the substrate face.

[0008] [Aspect 3] The wireless charging-type power supply device according to Aspect 1 or Aspect 2, wherein the power storage device is disposed between the first main surface of the substrate and the first antenna. With this configuration, the power storage device can be easily accommodated in the housing. This makes it easy to employ a large-sized power storage device and first antenna.

[0009] [Aspect 4] The wireless charging-type power supply device according to any one of Aspects 1 to 3, wherein the first antenna and the second antenna are flexible printed circuit board antennas and are arranged along the inner periphery of the housing. In this configuration, by using flexible printed circuit board antennas, the first antenna and the second antenna can be easily deformed along the inner periphery of the housing. Therefore, the first antenna and the second antenna can be easily accommodated within the housing. [Effects of the Invention]

[0010] The power receiving range of the wireless charging type power supply device can be expanded. [Brief explanation of the drawings]

[0011] [Figure 1] 1 is a block diagram showing a configuration of a wireless charging type power supply device according to an embodiment. [Figure 2] 1 is a perspective view of a wireless charging type power supply device according to an embodiment. [Figure 3] 1A and 1B are a side view and a cross-sectional view of a wireless charging type power supply device according to an embodiment. [Figure 4] FIG. 1 is an exploded perspective view of a wireless charging type power supply device according to an embodiment. [Figure 5] 1 is a plan view showing an internal configuration of a wireless charging type power supply device according to an embodiment. FIG. [Figure 6] FIG. 2 is a perspective view showing the arrangement of a substrate and an antenna of the wireless charging type power supply device according to the embodiment. [Figure 7] FIG. 7 is a cross-sectional view taken along line 7-7 in FIG. 6. [Figure 8] FIG. 2 is a plan view showing a power receiving antenna according to the embodiment. [Figure 9] 10 shows a simulation result of a radiation pattern of the wireless charging type power supply device according to the embodiment. DETAILED DESCRIPTION OF THE INVENTION

[0012] An embodiment will be described below. [Circuit configuration of wireless charging power supply device] 1 shows the circuit configuration of a wireless charging type power supply device 10 according to this embodiment. The wireless charging type power supply device 10 includes a pair of power receiving antennas, that is, a first antenna 70 and a second antenna 72, a communication antenna 14, a power storage device 16, and a power receiving circuit 20.

[0013] The first antenna 70 and the second antenna 72 receive power supplied from outside the wireless charging type power supply device 10. The power received by the first antenna 70 and the second antenna 72 is input to the power receiving circuit 20. The power receiving circuit 20 includes a rectifier circuit 20a, a charging circuit 20b, a control circuit 20c, and a communication control unit 20d.

[0014] The rectifier circuit 20a converts AC power received by the first antenna 70 and the second antenna 72 into DC power. The charging circuit 20b charges the DC power output from the rectifier circuit 20a into the power storage device 16. The control circuit 20c operates the charging circuit 20b to control the amount of charge to the power storage device 16.

[0015] The communication control unit 20d communicates with the outside of the wireless rechargeable power supply device 10 via the communication antenna 14. For example, the communication control unit 20d transmits an identification signal of the wireless rechargeable power supply device 10 to the outside via the communication antenna 14. For example, the communication antenna 14 is an antenna that receives microwaves in the frequency band of 5.7 to 5.8 GHz. This allows the wireless rechargeable power supply device 10 to function as a beacon. By transmitting the identification signal, an external power supply device can detect the presence of the wireless rechargeable power supply device 10. The power supply device transmits power wirelessly on the condition that it detects the presence of the wireless rechargeable power supply device 10. The communication control unit 20d may further be configured to exchange information regarding the amount of supplied power with the power supply device. For example, the communication method adopted by the communication control unit 20d is BLE (registered trademark: Bluetooth Low Energy).

[0016] The power storage device 16 is, for example, a secondary battery. Examples of the secondary battery include a lithium ion secondary battery and a nickel-metal hydride secondary battery. The power storage device 16 is not limited to a secondary battery and may be, for example, a capacitor.

[0017] [Wireless charging device layout] FIG. 2 shows the external shape of the wireless rechargeable power supply device 10. The wireless rechargeable power supply device 10 has the same shape as a dry cell battery. In particular, the wireless rechargeable power supply device 10 has the same shape and dimensions as, for example, an AA dry cell battery. The wireless rechargeable power supply device 10 is a cylindrical member. The wireless rechargeable power supply device 10 has a protruding positive electrode 40 on the top surface of the cylinder. The wireless rechargeable power supply device 10 accommodates the members shown in FIG. 1 in a space partitioned by a first housing 30 and a second housing 32. Hereinafter, the first housing 30 and the second housing 32 will be collectively referred to as the housing 33. The housing 33 is cylindrical.

[0018] 3 shows a side view, a front view of the cylindrical top and bottom surfaces, and an AA cross-sectional view of the wireless charging-type power supply device 10. As shown in Fig. 3, the wireless charging-type power supply device 10 has a positive electrode 40 formed on the top surface of the cylinder and a negative electrode 42 formed on the bottom surface.

[0019] FIG. 4 shows an exploded perspective view of the wirelessly rechargeable power supply device 10. As shown in FIG. 4, the wirelessly rechargeable power supply device 10 includes a chassis 60 in a space defined by the housing 33. A substrate 62 is fixed to the chassis 60. The substrate 62 has a first main surface 62a and a second main surface 62b opposite to the first main surface 62a, and is rectangular in shape with its longitudinal direction aligned with the longitudinal direction of the housing 33, in other words, the axial direction of the cylindrical housing 33. The substrate 62 is disposed such that the first main surface 62a faces the first housing 30 and the second main surface 62b opposite to the first main surface 62a faces the second housing 32. The power storage device 16 is disposed between the first main surface 62a of the substrate 62 and the housing 33.

[0020] 5 is a view of the substrate 62 viewed from the first main surface 62a side. A first coaxial cable 80 connected to the first antenna 70 and a coaxial cable 82 connected to the second antenna 72 extend on the first main surface 62a of the substrate 62 along the longitudinal direction of the substrate 62. In addition, an electrode cable 36 connected to the positive electrode 40 and an electrode cable 38 connected to the negative electrode 42 extend from the second main surface 62b side onto the second main surface 62b of the substrate 62.

[0021] [Details of the first and second antennas] 6 and 7 show the layout of the first antenna 70 and the second antenna 72. In FIG. 6, the longitudinal direction of the rectangular substrate 62 is depicted as the Z axis. The substrate 62 is depicted as being parallel to the plane defined by the Z axis and the Y axis. In FIG. 7, the housing 33 is depicted by imaginary lines.

[0022] The first antenna 70 and the second antenna 72 are both dipole antennas. The first antenna 70 and the second antenna 72 are both flexible printed circuit board antennas (FPC antennas).

[0023] FIG. 8 shows the configuration of the first antenna 70 and the second antenna 72. The first antenna 70 and the second antenna 72 are formed by forming a pattern of an element Em on a rectangular flexible printed circuit board Fp having a longitudinal direction and a lateral direction. The element Em is a conductor. As an example, the element Em is a copper foil pattern. Radio waves are transmitted through the first antenna 70 and the second antenna 72 via the element Em. When in a flat state, the element Em has a rectangular shape with a T-shaped notch SL. The element Em extends along the longitudinal direction D of the flexible printed circuit board Fp.

[0024] 6 and 7 show the shapes of the first antenna 70 and the second antenna 72 when they are housed in a space partitioned by the housing 33. Therefore, the first antenna 70 and the second antenna 72 have a shape that conforms to the inner circumferential surface of the housing 33. This is because the first antenna 70 and the second antenna 72 are FPC antennas and therefore have flexibility. The first antenna 70 and the second antenna 72 can be deformed into a shape that conforms to the inner circumferential surface of the housing 33. Note that, in one example, the first housing 30 and the second housing 32 are fixed by being attached to the inner circumferential surface of the housing 33.

[0025] Within the housing 33, the first antenna 70 is located on the first main surface 62a side of the substrate 62 and is disposed such that the longitudinal direction D of the flexible printed circuit board Fp coincides with the longitudinal direction (Z-axis direction) of the substrate 62. The first antenna 70 has an extension direction D1 of the element Em coincident with the longitudinal direction (Z-axis direction) of the substrate 62. The longitudinal direction of the substrate 62 can also be said to be the longitudinal direction of the housing 33.

[0026] Within the housing 33, the second antenna 72 is located on the second main surface 62b side of the substrate 62 and is disposed such that the longitudinal direction D of the flexible printed circuit board Fp coincides with the longitudinal direction (Z-axis direction) of the substrate 62. In the second antenna 72, the direction D2 in which the element Em extends coincides with the longitudinal direction (Z-axis direction) of the substrate 62.

[0027] The direction D1 in which the element Em of the first antenna 70 extends is the same as the direction D2 in which the element Em of the second antenna 72 extends. Here, the direction D1 and the direction D2 being the same includes a state in which the two directions are completely aligned, as well as a state in which they are slightly misaligned within a range of 15 degrees or less. It is preferable that the direction D1 and the direction D2 be completely aligned.

[0028] The first antenna 70 functions as a dipole antenna having directivity in the positive direction of the X-axis. The second antenna 72 functions as a dipole antenna having directivity in the negative direction of the X-axis. More specifically, as described above, the first antenna 70 and the second antenna 72 have an arch shape curved around the axis of the housing 33 along the inner circumferential surface of the housing 33. As a result, the first antenna 70 functions as a dipole antenna having directivity centered on the positive direction of the X-axis and extending to the positive and negative sides of the Y-axis. Similarly, the second antenna 72 functions as a dipole antenna having directivity centered on the negative direction of the X-axis and extending to the positive and negative sides of the Y-axis.

[0029] Next, the arrangement of the first antenna 70 and the second antenna 72 in the longitudinal direction (Z-axis direction) of the housing 33 and in the circumferential direction of the housing 33 will be described. The first antenna 70 is preferably disposed near the longitudinal center of the housing 33. For example, the first antenna 70 is preferably disposed so that at least a portion of the element Em overlaps with the longitudinal center of the housing 33, and more preferably so that the longitudinal center of the housing 33 overlaps with the center of the first antenna 70 in the direction D1 in which the element Em extends.

[0030] Similarly, the second antenna 72 is preferably disposed near the longitudinal center of the housing 33. For example, the second antenna 72 is preferably disposed so that at least a portion of the element Em overlaps with the longitudinal center of the housing 33, and more preferably so that the longitudinal center of the housing 33 overlaps with the center of the direction D2 in which the element Em of the second antenna 72 extends. Note that the relative positions of the first antenna 70 and the second antenna 72 in the longitudinal direction of the housing 33 are not particularly limited, but are preferably the same.

[0031] The first antenna 70 and the second antenna 72 are preferably disposed at positions spaced apart in the circumferential direction of the housing 33. For example, as shown in Fig. 7, the angle by which the first antenna 70 and the second antenna 72 are spaced apart in the circumferential direction around the substrate 62 in a side view seen from the direction D1 in which the element Em of the first antenna 70 extends is defined as angle θ. In this case, the angle θ is, for example, 165 degrees or more and 180 degrees or less, preferably 170 degrees or more and 180 degrees or less, and more preferably 180 degrees. The circumferential direction around the substrate 62 in a side view seen from the direction D1 in which the element Em of the first antenna 70 extends can also be considered as the circumferential direction around the central axis extending in the longitudinal direction (Z-axis direction) of the housing 33.

[0032] [Effect] The wireless charging-type power supply device 10 includes a pair of dipole antennas, a first antenna 70 and a second antenna 72. The first antenna 70 is a dipole antenna having directivity in the direction of the first main surface 62a of the substrate 62 (positive direction of the X-axis). The second antenna 72 is a dipole antenna having directivity in the direction of the second main surface 62b of the substrate 62 (negative direction of the X-axis). The first antenna 70 and the second antenna 72 have the same directions D1 and D2 in which their elements Em extend. Therefore, the first antenna 70 and the second antenna 72 have the same directions D1 and D2 in which their elements Em extend, but have opposite directivities in the thickness direction of the substrate 62. In this case, the first antenna 70 and the second antenna 72 complement each other in the direction in which their sensitivity is weak in the thickness direction of the substrate 62, thereby expanding the power receiving range in the same direction.

[0033] 9 shows a simulation result of the radiation pattern of the wireless charging-type power supply device 10 when the first antenna 70 and the second antenna 72 are arranged as in the embodiment. As shown in each diagram in FIG. 9, the first antenna 70, whose power receiving range expands in the positive direction of the X-axis, and the second antenna 72, whose power receiving range expands in the negative direction of the X-axis, complement each other's power receiving ranges, thereby greatly expanding the entire power receiving range in the X-axis direction. Furthermore, in the area where the power receiving range of the first antenna 70 and the power receiving range of the second antenna 72 overlap, the antenna gains are added together, so the above configuration also contributes to improving the antenna gain.

[0034] 9, the power receiving range of the second antenna 72 also extends in the Z-axis direction, ensuring a sufficient power receiving range in the Z-axis direction. Therefore, with the above configuration, it is possible to prevent the gain in the Z-axis direction from becoming 0.

[0035] [effect] (1) The wireless charging-type power supply device 10 includes a housing 33, a substrate 62, a power storage device 16, and a power receiving antenna accommodated within the housing 33. The substrate 62 has a first main surface 62a and a second main surface 62b opposite the first main surface 62a. A power receiving circuit 20 is mounted on the substrate 62, and the power receiving circuit 20 charges the power storage device 16 with power received by the power receiving antenna. The power receiving antenna includes a first antenna 70 located on the first main surface 62a side of the substrate 62 and a second antenna 72 located on the second main surface 62b side of the substrate 62. The first antenna 70 and the second antenna 72 are dipole antennas. The direction D1 in which the element Em of the first antenna 70 extends coincides with the direction D2 in which the element Em of the second antenna 72 extends. This configuration allows for an expanded power receiving range in the direction in which the first main surface 62a and the second main surface 62b of the substrate 62 face (the X-axis direction).

[0036] (2) In a side view seen from the direction D1 in which the element Em of the first antenna 70 extends, the first antenna 70 and the second antenna 72 are disposed at positions spaced apart by approximately 180 degrees in the circumferential direction around the substrate 62. According to the above configuration, the effect of expanding the power receiving range in the direction in which the first main surface 62a and the second main surface 62b of the substrate 62 face (the X-axis direction) can be more significantly achieved.

[0037] (3) The power storage device 16 is disposed between the first main surface 62a of the substrate 62 and the first antenna 70. According to the above configuration, the power storage device 16 can be easily accommodated in the housing 33. This makes it easy to employ a large-sized power storage device 16 and a large-sized first antenna 70.

[0038] (4) The first antenna 70 and the second antenna 72 are flexible printed circuit board antennas. The first antenna 70 and the second antenna 72 are arranged along the inner periphery of the housing 33. In the above configuration, by using an FPC antenna, the first antenna 70 and the second antenna 72 can be easily deformed along the inner periphery of the housing 33. Therefore, the first antenna 70 and the second antenna 72 can be easily accommodated within the housing 33.

[0039] <Example of change> The above embodiment can be modified as follows: The above embodiment and the following modifications can be combined with each other within the scope of technical compatibility.

[0040] The directions D1 and D2 in which the elements Em of the first antenna 70 and the second antenna 72 extend may coincide with the short-side direction (X-axis direction) of the substrate 62, or may be set independently of the direction in which the substrate 62 extends.

[0041] Regarding the first antenna and the second antenna, the shape of the FPC antenna does not necessarily have to be the shape illustrated in FIG. The first antenna 70 and the second antenna 72 may be dipole antennas, and are not necessarily FPC antennas. The first antenna 70 and the second antenna 72 may be different types of dipole antennas.

[0042] The power receiving antenna (hereinafter referred to as "other power receiving antenna") other than the first antenna 70 and the second antenna 72 may be provided. The number of other power receiving antennas may be one or more. The other power receiving antenna may be a dipole antenna or a known antenna other than a dipole antenna. The arrangement of the other power receiving antenna is not particularly limited and can be set arbitrarily depending on the layout inside the housing 33, etc. For example, the other power receiving antenna may be arranged so that the direction in which the element Em of the first antenna 70 extends is perpendicular to the direction D1 in which the element Em extends.

[0043] There may be two or more power storage devices 16. For example, in a configuration including two power storage devices 16, it is preferable to place a power storage device 16 between the first main surface 62a of the substrate 62 and the first antenna 70 and between the second main surface 62b of the substrate 62 and the second antenna 72. The placement of the power storage devices 16 can be changed as desired.

[0044] The use of the communication antenna 14 is not limited to making the wirelessly rechargeable power supply device 10 function as a beacon. For example, it may be used to transmit data on the discharge current of the wirelessly rechargeable power supply device 10 at each time. This makes it possible to collect data on the amount of power consumed by the user of the wirelessly rechargeable power supply device 10 and the time periods during which power is consumed.

[0045] The wireless rechargeable power supply device 10 does not necessarily have to include the communication antenna 14. It is not essential that the first main surface 62a and the second main surface 62b of the substrate 62 are rectangular. For example, as will be described later, if the wirelessly rechargeable power supply device 10 has a shape different from that of a dry cell, the housing 33 may have a shape whose longitudinal direction cannot be defined. In that case, the shape of the substrate 62 may be a square or other shape whose longitudinal direction cannot be defined.

[0046] It is not essential to provide a separate coaxial cable for connecting the antenna and the rectifier circuit 20a for each antenna. The wireless rechargeable power supply device 10 does not necessarily have to have the same shape and dimensions as an AA dry battery. For example, the wireless rechargeable power supply device 10 may have the same shape and dimensions as a D dry battery. Also, for example, the wireless rechargeable power supply device 10 may have the same shape and dimensions as a C dry battery. Also, for example, the wireless rechargeable power supply device 10 may have the same shape and dimensions as a AAA dry battery.

[0047] The wireless charging type power supply device 10 is not limited to a cylindrical device. For example, it may be a rectangular parallelepiped device such as a 9V dry cell battery. The wireless charging type power supply device 10 does not necessarily have to have the same dimensions and shape as a dry cell battery.

[0048] [Note] Next, the technical ideas that can be understood from the above-described embodiment and modified examples will be described below. [Appendix 1] The substrate is rectangular having a longitudinal direction and a lateral direction, and the direction in which the elements of the first antenna and the second antenna extend coincide with the longitudinal direction of the substrate.

[0049] [Supplementary Note 2] The wireless rechargeable power supply device includes a first coaxial cable and a second coaxial cable, wherein the first antenna is connected to the charging circuit via the first coaxial cable and the second antenna is connected to the charging circuit via the second coaxial cable. With the above configuration, loss due to noise can be reduced compared to when the first antenna and the second antenna are connected to the charging circuit by the same coaxial cable.

[0050] [Supplementary Note 3] The wireless rechargeable power supply device includes a communication antenna and a communication control unit, the communication antenna is configured to receive radio waves from outside the wireless rechargeable power supply device and transmit radio waves to the outside, and the communication control unit is configured to control communication with the outside. With the above configuration, the wireless rechargeable power supply device can communicate with the outside.

[0051] [Appendix 4] The wireless charging type power supply device has a cylindrical shape and is provided with a positive electrode on the top surface and a negative electrode on the bottom surface. With the above configuration, the wireless charging type power supply device can be made to have the same shape as a dry battery. Furthermore, by matching the dimensions, it can be made to have the same dimensions and shape as a dry battery. [Explanation of symbols]

[0052] D,D1,D2…direction Em…Element Fp...Flexible printed circuit board 10...Wireless charging power supply device 16...Electricity storage device 20b…Charging circuit 30...1st housing 32...Second housing 33…Housing 62... Circuit board 62a...First principal surface 62b...Second principal surface 70...First antenna 72...Second antenna

Claims

1. A wireless charging type power supply device including a housing, and a substrate, a power storage device, and a power receiving antenna accommodated in the housing, the substrate has a first major surface and a second major surface opposite to the first major surface; a power receiving circuit that charges the power storage device with power received by the power receiving antenna is mounted on the board; the power receiving antenna includes a first antenna located on the first main surface side of the substrate and a second antenna located on the second main surface side of the substrate, the first antenna and the second antenna are dipole antennas, A wireless charging type power supply device, wherein the direction in which the element of the first antenna extends is the same as the direction in which the element of the second antenna extends.

2. 2. The wireless charging type power supply device according to claim 1, wherein, in a side view seen from the direction in which the element of the first antenna extends, the first antenna and the second antenna are arranged at positions spaced apart at an angle in the range of 165 degrees or more and 180 degrees or less in the circumferential direction around the substrate.

3. The wireless charging type power supply device according to claim 1 , wherein the power storage device is disposed between the first main surface of the substrate and the first antenna.

4. the first antenna and the second antenna are flexible printed circuit board antennas; The wireless charging type power supply device according to claim 1 , wherein the first antenna and the second antenna are arranged along an inner periphery of the housing.

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