Coil unit

Abstract

To suppress deformation of a case while suppressing deformation of a stored apparatus, in a coil unit used for contactless power supply.SOLUTION: Coil units 10, 10A, 10B, 10C, and 10D include: a substrate 12; covers 11, 11A, 11C, and 11D for forming a sealed space between the covers and the substrate; magnetic plates 13, 13A, 13B, and 13C arranged on the substrate in a sealed space; coils 112, 212 for transmitting or receiving AC power, the coils being placed on the magnetic plates in a lamination direction in the sealed space; and a fluid substance with fluidity sealed in the sealed space.SELECTED DRAWING: Figure 4

Description

Technical Field

[0001] The present disclosure relates to a coil unit.

Background Art

[0002] A coil unit used in a non-contact power supply system that supplies power from a power transmission device to a vehicle equipped with a power reception device is known. The coil unit described in Patent Document 1 accommodates a device in a device accommodation space defined by a base and a protective cover, and suppresses deformation of the protective cover by receiving an external force applied to the protective cover with the device in contact with the protective cover.

Prior Art Documents

Patent Documents

[0003]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0004] However, in the coil unit described in Patent Document 1, there is a risk that the device may be damaged by an external force. Further, when an external force is applied to a portion of the protective cover that is not in contact with the device, deformation may occur. Therefore, a technique capable of suppressing deformation of the protective cover while suppressing deformation of the device accommodated in the protective cover is desired.

Means for Solving the Problems

[0005] The present disclosure can be realized in the following forms.

[0006] According to one embodiment of the present disclosure, a coil unit (10, 10A, 10B, 10C, 10D) used in a non-contact power supply system (300) is provided. The coil unit includes a substrate (12), a cover (11, 11A, 11C, 11D) that forms a sealed space between the substrate, a magnetic plate (13, 13A, 13B, 13C) placed on the substrate within the sealed space, and a coil (112, 212) for transmitting or receiving AC power, the coil being placed in a stacking direction on the magnetic plate within the sealed space, and a fluid substance having fluidity and enclosed in the sealed space.

[0007] According to the coil unit of this embodiment, since it includes a fluid substance enclosed in a sealed space, when an external force is applied to the cover and it is deformed, the volume of the sealed space is reduced and the pressure of the fluid substance increases, and a force that resists the reduction of the volume of the sealed space acts from the inside of the cover. Therefore, while suppressing local deformation of the equipment housed in the sealed space due to an external force, deformation of the cover due to the external force can be suppressed.

Brief Description of Drawings

[0008]

Figure 1

Figure 2

Figure 3

Figure 4

Figure 5

Figure 6

Figure 7

Figure 8

Figure 9

Figure 10

Figure 11

Figure 12

Mode for Carrying Out the Invention

[0009] A. First Embodiment: A1. Configuration of the Non-contact Power Supply System 300: The coil unit 10 of the first embodiment will be described with reference to FIGS. 1 to 5. The coil unit 10 of the first embodiment is used in the non-contact power supply system 300. As shown in FIG. 1, the non-contact power supply system 300 includes a power transmitter 100 installed on the road RS and a power receiver 205 mounted on the vehicle 200. The non-contact power supply system 300 is a system capable of supplying power from the power transmitter 100 to the power receiver 205 of the vehicle 200 in a non-contact manner. In the present embodiment, the coil unit 10 is provided in the power transmitter 100.

[0010] The power transmitter 100 of the present embodiment includes a coil unit 10 and a power supply circuit 130. The coil unit 10 has a power transmission resonance circuit 110 and a power transmission circuit 120. In the present embodiment, the coil unit 10 and the power supply circuit 130 are buried inside the road RS. A plurality of coil units 10 may be provided and arranged continuously, for example, along the extending direction of the road RS in the traveling direction of the vehicle 200. The coil unit 10 and the power supply circuit 130 do not necessarily have to be buried inside the road RS, and may be provided, for example, at a position on the road RS that does not obstruct the traveling of the vehicle 200. The power supply circuit 130 is preferably provided in the vicinity of the coil unit 10. Note that the power transmission resonance circuit 110 and the power transmission circuit 120 may be configured separately from the coil unit 10.

[0011] The power supply circuit 130 supplies AC power from an AC power source such as a utility power supply to the power transmission circuit 120 via a power cable. The power transmission circuit 120 is an AC conversion circuit having a rectifier circuit, an inverter circuit, a filter circuit, and the like. The power transmission circuit 120 converts the AC power supplied from the power supply circuit 130 into DC power, and then converts the DC power into high-frequency AC power capable of being transmitted to the power receiver 205 of the vehicle 200, and supplies it to the power transmission resonance circuit 110.

[0012] As shown in FIG. 2, the power transmission resonance circuit 110 is an LC circuit in which a power transmission side capacitor 116 functioning as a resonance capacitor and a power transmission coil 112 are connected in series. Note that the power transmission coil 112 and the power transmission side capacitor 116 may be connected in parallel. The power transmission resonance circuit 110 transmits the AC power induced in the power transmission coil 112 to the power reception resonance circuit 210 by using the electromagnetic induction phenomenon. The power transmission coil 112 is included in the coil unit 10 of the present embodiment.

[0013] The vehicle 200 is configured by a vehicle equipped with a drive motor such as an electric vehicle or a hybrid vehicle, for example. As shown in FIG. 1, the vehicle 200 includes a power receiver 205 and a battery 230. The power receiver 205 has a power reception resonance circuit 210 and a power reception circuit 220. Note that the vehicle 200 is not limited to an automobile, and may be configured as a transport robot such as an AGV (Automatic Guides Vehicle) or an AMR (Autonomous Mobile Robot).

[0014] As shown in FIG. 2, the power reception resonance circuit 210 includes a power reception side capacitor 216 functioning as a resonance capacitor and a power reception coil 212. The power reception resonance circuit 210 is disposed, for example, on the bottom surface of the vehicle 200. The power reception resonance circuit 210 receives the AC power induced in the power transmission resonance circuit 110 of the power transmitter 100 from the power reception coil 212.

[0015] The power receiving circuit 220 converts the AC power output from the power receiving resonance circuit 210 into DC power. The power receiving circuit 220 includes, for example, a filter circuit, a rectifier circuit that converts AC power into DC power, and a power conversion circuit that converts the DC power into DC power suitable for charging the battery 230. The battery 230 is, for example, a secondary battery that outputs DC power for driving a drive motor that is a drive source of the vehicle 200. The DC power output from the power receiving circuit 220 can be used for charging the battery 230. The DC power from the power receiving circuit 220 may be used for charging an auxiliary battery (not shown) or driving the drive motor and auxiliary equipment.

[0016] A-2. Configuration of the coil unit 10: Next, the configuration of the coil unit 10 will be described with reference to FIG. 3. As shown in FIG. 3, the coil unit 10 includes a cover 11, an aluminum plate 12, a ferrite plate 13, and a power transmission coil 112. In FIG. 3, only the power transmission coil 112 of the power transmission resonance circuit 110 and the power transmission circuit 120 is shown, and the illustration of other configurations is omitted. The coil unit 10 may include, for example, the power transmission resonance circuit 110, the power transmission circuit 120, and any other members included in the power supply circuit 130.

[0017] Note that the coil unit 10 further includes a partition plate 31 (see FIG. 4). However, the detailed configuration of the partition plate 31 will be described with reference to the figures after FIG. 4, and the illustration is omitted in FIG. 3. Similarly, the illustration of the through hole 41 provided in the ferrite plate 13 is omitted.

[0018] The cover 11 is cup-shaped and has a rectangular appearance in plan view. By fitting the cover 11 and the aluminum plate 12 via a sealing member (not shown), a sealed space is formed that houses the power transmission coil 112, the ferrite plate 13, and the aluminum plate 12. As the sealing member, an O-ring, a liquid gasket, or the like may be used. Inside the sealed space, the ferrite plate 13 is placed on the aluminum plate 12, and the power transmission coil 112 is placed on the aluminum plate 12. In the following description, the direction in which the aluminum plate 12, the ferrite plate 13, and the power transmission coil 112 are stacked is also referred to as the "stacking direction". Also, the upper surface of each member in the stacking direction when the cover 11 is in the upper position is also referred to as the "upper surface", and the lower surface in the stacking direction is also referred to as the "lower surface".

[0019] The cover 11 is non-conductive and is formed of a non-magnetic material such as resin, for example. By forming the cover 11 of a non-magnetic material, it is possible to reduce or prevent the magnetic flux generated from the power transmission coil 112 from being blocked. The upper surface of the cover 11 is the surface that faces the power reception coil 212 of the vehicle 200 among the surfaces of the coil unit 10. The lower surface of the cover 11 covers the upper surface of the power transmission coil 112 and protects the power transmission coil 112 from the outside air and the like. In the present embodiment, the cover 11 is buried in the road RS, but it may also be exposed from the road RS.

[0020] The aluminum plate 12 has a rectangular appearance in plan view. The aluminum plate 12 is provided in a state where its upper surface is in contact with the lower surface of the ferrite plate 13. The aluminum plate 12 is formed of aluminum or an aluminum alloy. The aluminum plate 12 dissipates the heat generated in the power transmission coil 112. Also, the aluminum plate 12 has a function of shielding the magnetic flux generated from the power transmission coil 112 so that it does not escape to the outside. Note that instead of the aluminum plate 12, a plate member for heat dissipation and shielding may be configured by copper or other metal plates. The aluminum plate 12 corresponds to the "substrate" in the present disclosure.

[0021] The ferrite plate 13 has a rectangular appearance shape in plan view. On the upper surface of the ferrite plate 13, the power transmission coil 112 is placed. In the present embodiment, the ferrite plate 13 is provided in a state of being in contact with the lower surface of the power transmission coil 112, but the ferrite plate 13 may be provided in a state of being separated from the lower surface of the power transmission coil 112. The ferrite plate 13 corresponds to the "magnetic plate" in the present disclosure. Note that instead of the ferrite plate 13, a plate material formed of a dust core or a nanocrystalline soft magnetic material may be used as the magnetic plate.

[0022] In the present embodiment, the power transmission coil 112 is formed by winding a conductor such as a magnet wire so as to surround the periphery of the central axis CX. Note that the power transmission coil 112 may be formed by resin-molding a magnet wire wound in a coil shape. Further, the power transmission coil 112 may be, for example, a spiral coil obtained by cutting out a conductor in a spiral shape, or various coils such as a helical coil in which a conductor having a circular or rectangular cross-sectional shape is wound in a spiral shape. When a conductor is used for the power transmission coil 112, the conductor may be formed of a stranded wire.

[0023] The power transmission coil 112 has a hollow region that does not contain a conductor at a position including the central axis CX. The central axis CX is the central axis CX of the coil unit 10, passes through the centers of the aluminum plate 12, the ferrite plate 13, and the power transmission coil 112, and extends in the vertical direction. In the present embodiment, the extending direction of the central axis CX is parallel to the stacking direction. That is, the power transmission coil 112 of the present embodiment is formed by being wound in a direction intersecting the stacking direction.

[0024] When an alternating current flows through the power transmission coil 112, a magnetic flux is formed around the power transmission coil 112. The magnetic flux formed around the power transmission coil 112 passes through the hollow region of the power transmission coil 112, the ferrite plate 13, and the outer peripheral side of the power transmission coil 112. When a part of the magnetic flux formed around the power transmission coil 112 links with the power reception coil 212, an alternating current flows through the power reception coil 212. When an alternating current flows through the power reception coil 212, a magnetic flux is also formed around the power reception coil 212. The power reception coil 212 receives power from the power transmission coil 112 in a non-contact manner by the magnetic flux that links with both the power transmission coil 112 and the power reception coil 212.

[0025] In FIG. 4, for ease of understanding, the illustration of the cover 11 is omitted, and each member inside the cover 11 as viewed from the cover 11 side is illustrated. A partition plate 31 is provided inside the cover 11. As shown in FIG. 4, the partition plate 31 has an annular shape whose outer edge has a rectangular shape in plan view, and is disposed in the hollow region of the power transmission coil 112 shown with hatching. Further, as shown in FIG. 5, in the present embodiment, the partition plate 31 extends along the stacking direction from the lower surface of the cover 11 and is integrally formed with the cover 11. Note that the partition plate 31 may be formed as a separate member from the cover 11.

[0026] As shown in FIG. 5, the ferrite plate 13 of the present embodiment has a through-hole 41. The end of the partition plate 31 is inserted into the through-hole 41 and abuts against the aluminum plate 12 in a state where the cover 11 and the aluminum plate 12 are fitted together. Thereby, when an external force is applied to the cover 11, since the external force is supported by the aluminum plate 12 via the partition plate 31, deformation of the cover 11 due to the external force can be suppressed. Further, since the tip of the partition plate 31 in the stacking direction is inserted into the through-hole 41 and does not abut against the ferrite plate 13, application of the external force applied to the cover 11 to the ferrite plate 13 can be suppressed, and deformation of the ferrite plate 13 due to the external force can be suppressed.

[0027] The partition plate 31 partitions a sealed space in a state where the cover 11 and the aluminum plate 12 are fitted together. In other words, the partition plate 31 divides the sealed space formed between the cover 11 and the aluminum plate 12 into an outer sealed space and an inner sealed space outside the partition plate 31. In the present embodiment, a fluid substance is enclosed in each of the plurality of sealed spaces divided by the partition plate 31. In the present embodiment, oil is enclosed as the fluid substance. When an external force is applied to the cover 11 and it deforms, the volume of the sealed space is reduced and the pressure of the fluid substance increases, and a force that resists the reduction of the volume of the sealed space acts from the inside of the cover 11. Therefore, deformation of the cover 11 due to an external force can be suppressed. Further, since the fluid substance has fluidity, the external force applied to the cover 11 can be dispersed by the fluid substance, and it is possible to suppress a local external force from acting on the cover 11.

[0028] According to the coil unit 10 of the first embodiment described above, since it includes a fluid substance enclosed in a sealed space, when an external force is applied to the cover 11 and it deforms, the volume of the sealed space is reduced and the pressure of the fluid substance increases, and a force that resists the reduction of the volume of the sealed space acts from the inside of the cover 11. Therefore, while suppressing local external force from acting on and deforming the equipment housed in the sealed space, deformation of the cover 11 due to an external force can be suppressed.

[0029] Further, since it includes the partition plate 31, the pressure of the fluid substance increased by applying an external force to the cover 11 can be received by the partition plate 31, and it is possible to suppress local pressure from being applied to the outer edge portion of the cover 11.

[0030] Further, since the ferrite plate 13 has a through-hole 41 and the partition plate 31 is inserted into the through-hole 41 and does not contact the ferrite plate 13, it is possible to suppress an external force applied to the cover 11 from being applied to the ferrite plate 13, and it is possible to suppress the ferrite plate 13 from deforming due to an external force. In addition, since the end portion of the partition plate 31 is inserted into the through-hole 41 and contacts the aluminum plate 12, when an external force is applied to the cover 11, the aluminum plate 12 can support the external force via the partition plate 31, and deformation of the cover 11 can be suppressed.

[0031] B. Second Embodiment: As shown in FIGS. 6, 7, and 8, the coil unit 10A of the second embodiment is different from the coil unit 10 of the first embodiment in that it includes a first power transmission resonance circuit 110a and a second power transmission resonance circuit 110b instead of the power transmission resonance circuit 110, includes a ferrite plate 13A instead of the ferrite plate 13, and includes a partition plate 31a and a partition plate 31b instead of the partition plate 31. Since the device configuration of the coil unit 10A of the second embodiment is the same as that of the coil unit 10 of the first embodiment, the same reference numerals are given to the same components, and detailed descriptions thereof are omitted.

[0032] The circuit configurations of the first power transmission resonance circuit 110a and the second power transmission resonance circuit 110b will be described with reference to FIG. 6. The first power transmission resonance circuit 110a has a first power transmission coil 112a and a first power transmission side capacitor 116a connected in series to each other. The second power transmission resonance circuit 110b has a second power transmission coil 112b and a second power transmission side capacitor 116b connected in series to each other. Here, the first power transmission coil 112a corresponds to the "first coil" in the present disclosure. The first power transmission side capacitor 116a corresponds to the "first capacitor" in the present disclosure. The second power transmission coil 112b corresponds to the "second coil" in the present disclosure. The second power transmission side capacitor 116b corresponds to the "second capacitor" in the present disclosure.

[0033] The first power transmission coil 112a included in the first power transmission resonance circuit 110a and the second power transmission coil 112b included in the second power transmission resonance circuit 110b are not electrically connected to each other. The first power transmission coil 112a and the first power transmission side capacitor 116a, and the second power transmission coil 112b and the second power transmission side capacitor 116b are configured such that the resonance frequency of the first power transmission resonance circuit 110a and the resonance frequency of the second power transmission resonance circuit 110b match each other. By making the resonance frequency of the first power transmission resonance circuit 110a and the resonance frequency of the second power transmission resonance circuit 110b match each other, the reactive power component of the alternating current power in the first power transmission coils 112a and 112b can be suppressed, and a decrease in the power supply efficiency in the non-contact power supply system 300 can be suppressed.

[0034] With reference to FIGS. 7 and 8, the configuration of the coil unit 10A of the present embodiment will be described. As shown in FIG. 7, the first power transmission coil 112a and the second power transmission coil 112b are arranged concentrically on the ferrite plate 13A and are not electrically connected to each other. In the present disclosure, "concentric" does not require that the central axis CX of the first power transmission coil 112a and the central axis CX of the second power transmission coil 112b exactly coincide. Further, the planar shape of the outer edge of each coil is not limited to a circular shape, and may be any annular shape.

[0035] As shown in FIG. 8, the ferrite plate 13A has a through portion 41a and a through portion 41b. The through portion 41a is provided corresponding to the space formed in the radial gap between the first power transmission coil 112a and the second power transmission coil 112b, and the through portion 41b is provided so as to be located radially inside the second power transmission coil 112b.

[0036] As shown in FIG. 8, the partition plates 31a and 31b extend along the stacking direction from the lower surface of the cover 11A and are integrally formed with the cover 11. Note that at least one of the partition plates 31a and 31b may be formed as a member separate from the cover 11A. The end of the partition plate 31b is inserted into the through hole 41b and abuts against the aluminum plate 12 in a state where the cover 11A and the aluminum plate 12 are fitted together. Further, the end of the partition plate 31a is inserted into the radial gap between the first power transmission coil 112a and the second power transmission coil 112b and the through hole 41a and abuts against the aluminum plate 12 in a state where the cover 11A and the aluminum plate 12 are fitted together. Therefore, when an external force is applied to the cover 11, the external force is supported by the aluminum plate 12 via the partition plates 31a and 31b. Thus, compared with a form in which the cover 11 is supported only by the aluminum plate 12 via only the partition plate 31a, deformation of the cover 11 due to the external force can be more effectively suppressed. Further, the tip of the partition plate 31a is inserted into the radial gap between the first power transmission coil 112a and the second power transmission coil 112b and the through hole 41a and does not abut against the first power transmission coil 112a, the second power transmission coil 112b, and the ferrite plate 13. Therefore, it is possible to suppress the external force applied to the cover 11A from being applied to each member, and to suppress deformation of each member due to the external force.

[0037] According to the coil unit 10A of the second embodiment described above, the same effects as those of the first embodiment can be obtained. Further, the end of the partition plate 31a is inserted into the radial gap between the first power transmission coil 112a and the second power transmission coil 112b and the through hole 41a and abuts against the aluminum plate 12 in a state where the cover 11 and the aluminum plate 12 are fitted together. Therefore, also for the portion of the cover 11A corresponding to the radial gap between the first power transmission coil 112a and the second power transmission coil 112b, the external force can be supported by the aluminum plate 12 via the partition plate 31a, and deformation of the cover 11A due to the external force can be more effectively suppressed.

[0038] In addition, since the resonance frequencies of the first power transmission resonance circuit 110a and the second power transmission resonance circuit 110b match each other, the reactive power component of the alternating current power in the first power transmission coils 112a and 112b can be suppressed, and a decrease in the power transmission efficiency in the non-contact power supply system 300 can be suppressed.

[0039] C. Third Embodiment: As shown in FIGS. 9 and 10, the coil unit 10B of the third embodiment is different from the coil unit 10A of the second embodiment in that it includes a ferrite plate 13B instead of the ferrite plate 13A. Since the device configuration of the coil unit 10B of the third embodiment is the same as that of the coil unit 10A of the second embodiment, the same reference numerals are given to the same configurations, and detailed descriptions thereof are omitted. Note that FIG. 10 shows an enlarged view of a range AR surrounded by a broken line in FIG. 9.

[0040] As shown in FIGS. 9 and 10, the ferrite plate 13B has a protruding portion 51 that protrudes along a partition plate 31a inserted into a through hole 41a on the surface on which the first power transmission coil 112a and the second power transmission coil 112b are placed. Here, when compared with a form that does not have the through hole 41a, in the form that has the through hole 41a, since the magnetic material is interrupted at the through hole 41a, the magnetic resistance increases, and the power transmission efficiency in the non-contact power supply system 300 decreases. Therefore, in the present embodiment, by having the protruding portion 51, the area of the portion of the ferrite plate 13B that faces each other with the partition plate 31a interposed therebetween in the direction orthogonal to the stacking direction can be enlarged, so that a decrease in the magnetic flux in the portion where the magnetic material is interrupted by the through hole 41a can be suppressed, and an increase in the magnetic resistance can be suppressed. Thereby, a decrease in the power transmission efficiency in the non-contact power supply system 300 can be suppressed. In addition, in the present embodiment, in a state where the partition plate 31a is inserted into the through hole 41a, the protruding portion 51 and the partition plate 31b are in contact with each other. Thereby, the facing distance of the portion of the ferrite plate 13B that faces each other with the partition plate 31a interposed therebetween in the direction orthogonal to the stacking direction can be reduced, and an increase in the magnetic resistance can be suppressed.

[0041] Also, as shown in FIG. 10, in the present embodiment, the dimension of the protruding portion 51 along the stacking direction is larger than the dimensions of the first power transmission coil 112a and the second power transmission coil 112b along the stacking direction. Thereby, the magnetic flux generated by the current flowing through the first power transmission coil 112a is easily induced in the magnetic protruding portion 51, and the eddy current loss generated in the second power transmission coil 112b can be suppressed by the magnetic flux passing through the second power transmission coil 112b. Thereby, a decrease in power feeding efficiency in the non-contact power feeding system 300 can be suppressed.

[0042] According to the coil unit 10 of the third embodiment described above, the same effects as those of the second embodiment can be obtained. In addition, since the protruding portion 51 is provided, the area of the portions of the ferrite plate 13B that face each other with the partition plate 31a interposed therebetween in the direction orthogonal to the stacking direction can be increased, and a decrease in magnetic flux in the portion where the magnetic body is interrupted by the through portion 41a can be suppressed, and an increase in magnetic resistance can be suppressed. For this reason, a decrease in power feeding efficiency in the non-contact power feeding system 300 can be suppressed.

[0043] D. Fourth Embodiment: As shown in FIG. 11, the coil unit 10C of the fourth embodiment is different from the coil unit 10A of the second embodiment in that a cover 11C is provided instead of the cover 11A and a ferrite plate 13C is provided instead of the ferrite plate 13A. Since the device configuration of the coil unit 10C of the fourth embodiment is the same as that of the coil unit 10A of the second embodiment, the same reference numerals are given to the same configurations, and detailed description thereof is omitted.

[0044] The ferrite plate 13C is formed as a plate-shaped member having no through portion. According to the ferrite plate 13C of such a form, since there is no portion where the magnetic body is interrupted, an increase in magnetic resistance can be suppressed as compared with the form having a through portion.

[0045] Cover 11C has partition plates 31c and 31d instead of the partition plates 31a and 31b that the cover 11A of the second embodiment has. The partition plates 31c and 31d extend along the stacking direction from the lower surface of the cover 11C and are integrally formed with the cover 11C. In the present embodiment, the end of the partition plate 31c and the end of the partition plate 31d are separated along the stacking direction with respect to the ferrite plate 13C. Therefore, even when an external force is applied to the cover 11C, it is possible to suppress the transmission of the external force to the ferrite plate 13C and suppress the deformation of the ferrite plate 13C. Further, since the partition plates 31c and 31d are provided, the pressure of the fluid substance increased by the application of an external force to the cover 11 can be received by the partition plates 31c and 31d, and it is possible to suppress the local application of pressure to the outer edge portion of the cover 11C. Further, since the flow path can be narrowed between the tip portions of the partition plates 31c and 31d and the ferrite plate 13, the flow of the fluid substance between the regions partitioned by each partition plate can be suppressed.

[0046] According to the coil unit 10C of the fourth embodiment described above, since it includes a fluid substance enclosed in a sealed space, when an external force is applied to the cover 11C and it is deformed, the volume of the sealed space is reduced and the pressure of the fluid substance increases, and a force that resists the reduction of the volume of the sealed space acts from the inside of the cover 11C. Therefore, the deformation of the cover 11C due to the external force can be suppressed.

[0047] Further, since the partition plates 31c and 31d are provided, the pressure of the fluid substance increased by the application of an external force to the cover 11C can be received by the partition plates 31c and 31d, and it is possible to suppress the local application of pressure to the outer edge portion of the cover 11C. In addition, since the flow path can be narrowed between the tip portions of the partition plates 31c and 31d and the ferrite plate 13, the flow of the fluid substance between the regions partitioned by each partition plate can be suppressed.

[0048] Further, the end of the partition plate 31c and the end of the partition plate 31d are separated along the stacking direction with respect to the ferrite plate 13C. Therefore, even when an external force is applied to the cover 11C, it is possible to suppress the transmission of the external force to the ferrite plate 13C and suppress the deformation of the ferrite plate 13C.

[0049] E. Fifth Embodiment: As shown in FIG. 12, the coil unit 10D of the fifth embodiment is different from the coil unit 10 of the first embodiment in that it includes a cover 11D instead of the cover 11. Since the device configuration of the coil unit 10D of the fifth embodiment is the same as that of the coil unit 10 of the first embodiment, the same reference numerals are given to the same components, and detailed description thereof is omitted.

[0050] The cover 11D has an inlet 61 and an outlet 71, and an inlet 63 and an outlet 73 during the manufacture of the coil unit 10D. The inlet 61 and the outlet 71 are formed corresponding to the sealed space formed outside the partition plate 31, and the inlet 63 and the outlet 73 are formed corresponding to the sealed space formed inside the partition plate 31. Thus, when the sealed space is divided into a plurality by the partition plate, a pair of inlets and outlets are provided for each sealed space. The inlet 61 and the outlet 71, and the inlet 63 and the outlet 73 are sealed after the completion of the enclosure of the fluid substance.

[0051] The inlet 61 and the inlet 63 communicate the outside of the cover 11D with the sealed space and are used to enclose the fluid substance in the sealed space. Further, the outlet 71 and the outlet 73 communicate the outside of the cover 11D with the sealed space and are used to discharge the air present in the sealed space when enclosing the fluid substance.

[0052] On the inner surface side of the cover 11D, as it goes from the sealing inlet 61 to the discharge outlet 71 and as it goes from the sealing inlet 63 to the discharge outlet 73, it has an inclination such that the dimension along the stacking direction of the sealed space formed when the cover 11D and the aluminum plate 12 are fitted together increases. Thereby, when filling the sealed space with a fluid substance in a posture where the cover 11D is located above the aluminum plate 12, the air existing in the sealed space is likely to be induced to the discharge outlet 71 located above the sealing inlet 61 and the discharge outlet 73 located above the sealing inlet 63, and it is possible to suppress the air remaining in the sealed space.

[0053] According to the coil unit 10D of the fifth embodiment described above, it has the same effects as the first embodiment. In addition, it further includes a sealing inlet 61 and a discharge outlet 71, and a sealing inlet 63 and a discharge outlet 73. On the inner surface side of the cover 11D, as it goes from the sealing inlet 61 to the discharge outlet 71 and as it goes from the sealing inlet 63 to the discharge outlet 73, it has an inclination such that the dimension along the stacking direction of the sealed space formed when the cover 11D and the aluminum plate 12 are fitted together increases. Thereby, when filling the sealed section with a fluid substance in a posture where the cover 11D is located above the aluminum plate 12, the air existing in the sealed space is likely to be induced to the discharge outlets 71 and 73, and it is possible to suppress the air remaining in the sealed space.

[0054] F. Other Embodiments: (F1) In the above embodiment, the cover 11, the aluminum plate 12, and the ferrite plate 13 have a rectangular appearance shape in plan view, but the present disclosure is not limited thereto. The cover 11, the aluminum plate 12, and the ferrite plate 13 may have an arbitrary appearance shape such as a trapezoid or a circle in plan view. Also, the power transmission coil 112 may be wound into an arbitrary shape corresponding to the shapes of the cover 11, the aluminum plate 12, and the ferrite plate 13. Further, the partition plate 31 may have an arbitrary shape corresponding to the shape of the hollow region formed by winding the power transmission coil 112. The coil unit 10 in such a form also has the same effects as the above embodiment.

[0055] (F2) In the above embodiment, the power transmission coil 112 is wound in a direction intersecting the stacking direction such that the central axis CX is parallel to the stacking direction, but the present disclosure is not limited thereto. The power transmission coil 112 may be wound such that the central axis CX intersects the stacking direction. Even in such a form, the same effects as those of the above embodiment can be obtained.

[0056] (F3) In the above embodiment, the power transmission coil 112 is formed by winding a conductive wire such as a magnet wire so as to surround the periphery of the central axis CX, but the present disclosure is not limited thereto. The power transmission coil 112 may be formed by a conductive pattern formed on a printed wiring board. Even with the coil unit 10 in such a form, the same effects as those of the above embodiment can be obtained.

[0057] (F4) In the above embodiment, oil is enclosed in the sealed space as the fluid substance, but the present disclosure is not limited thereto. The fluid substance may be any substance having fluidity, such as a gas, a liquid, a powder, or a gel. Here, it is preferable that the fluid substance has a higher density than air in the standard state because the resistance to volume compression is greater than that of a substance having a lower density than air in the standard state. Note that a mixture of a powder and a liquid may be used as the fluid substance.

[0058] It is preferable that the fluid substance has a higher viscosity than water because the resistance when an external force is applied and it flows in the sealed space becomes greater. In the present embodiment, most of the external force applied to the coil unit 10 is an instantaneous load when the vehicle 200 rides on and passes over the power transmission coil 112. Therefore, the substance used as the fluid substance is not limited to a substance having a constantly high viscosity, and a substance whose viscosity temporarily increases when an external force is instantaneously applied, more specifically, a dilatant fluid, may be used as the fluid substance.

[0059] In addition, the lower the thermal resistance of the fluid substance, the easier it is to dissipate the heat generated in the power transmission coil 112. Also, the higher the electrical insulation of the fluid substance, the more effectively the leakage of the power transmission coil 112 can be suppressed, and the decrease in the power transmission efficiency in the non-contact power supply system 300 can be suppressed. Further, the fluid substance can increase the resistance against the deformation of the cover 11 by applying a higher pressure when filling the sealed space. Moreover, the higher the viscosity of the fluid substance, the more effectively the leakage of the fluid substance from the sealed space can be suppressed, and the decrease in the resistance against the reduction in the volume of the sealed space due to the leakage of the fluid substance can be suppressed.

[0060] (F5) In the above embodiment, the coil unit 10 is provided in the power transmitter 100, but the present disclosure is not limited thereto. The coil unit 10 may be provided in the vehicle 200.

[0061] (F6) In the above second embodiment, the first power transmission coil 112a and the first power transmission side capacitor 116a, and the second power transmission coil 112b and the second power transmission side capacitor 116b are each connected in series with each other, but the present disclosure is not limited thereto. The first power transmission coil 112a and the first power transmission side capacitor 116a may be connected in parallel with each other, and the second power transmission coil 112b and the second power transmission side capacitor 116b may be connected in parallel with each other. Even in such a configuration, the same effects as those of the above embodiment can be achieved.

[0062] (F7) In the above third embodiment, in the state where the partition plate 31a is inserted into the through portion 41a, the protruding portion 51 and the partition plate 31b are in contact with each other, but the present disclosure is not limited thereto. A gap may exist between the protruding portion 51 and the partition plate 31b. Even with the coil unit 10C of such a configuration, the same effects as those of the above third embodiment can be achieved. In addition, since a gap exists between the protruding portion 51 and the partition plate 31b, the insertion of the partition plate 31b into the protruding portion 51 and the through portion 41a can be facilitated.

[0063] (F8) In the above-described fourth embodiment, the coil unit 10C has the first power transmission coil 112a and the second power transmission coil 112b, but the present disclosure is not limited thereto. The coil unit 10C has the power transmission coil 112 as in the first embodiment, and the partition plate 31c may be formed such that its end is separated along the stacking direction with respect to the power transmission coil 112. Even in such a form, it is possible to suppress the external force applied to the cover 11C from being transmitted to the power transmission coil 112 and deforming the power transmission coil 112. In addition, it is not necessary to divide the coil in order to avoid contact between the partition plate 31c and the coil, and it is possible to suppress the configuration of the coil unit from becoming complicated.

[0064] Also, either one of the partition plate 31c and the partition plate 31d may be in contact with the power transmission coil 112 or the ferrite plate 13B. Even in such a form, it is possible to suppress the power transmission coil 112 or the ferrite plate 13B from being deformed by an external force as compared with a form in which both the partition plate 31c and the partition plate 31d are in contact with the power transmission coil 112 or the ferrite plate 13B.

[0065] (F9) In the above-described embodiment, the coil unit 10 includes the partition plate 31, but the present disclosure is not limited thereto. The coil unit 10 may not include the partition plate 31. Even in such a form, since it includes a fluid substance enclosed in a sealed space, when an external force is applied to the cover 11 and it is deformed, the volume of the sealed space is reduced and the pressure of the fluid substance increases, and a force that resists the reduction of the volume of the sealed space acts from the inside of the cover 11. Therefore, it is possible to suppress the deformation of the cover 11 due to an external force while suppressing the local application of an external force to the device housed in the sealed space and deforming it.

[0066] The present disclosure is not limited to the above-described embodiments, and can be implemented in various configurations without departing from the gist thereof. For example, the technical features in each embodiment corresponding to the technical features in the forms described in the summary of the invention can be appropriately replaced or combined in order to solve some or all of the above-described problems, or to achieve some or all of the above-described effects. Further, if the technical feature is not described as essential in this specification, it can be appropriately deleted. (Form 1) A coil unit (10, 10A, 10B, 10C, 10D) used in a non-contact power supply system (300), a substrate (12), a cover (11, 11A, 11C, 11D) that forms a sealed space between the substrate and the cover, a magnetic plate (13, 13A, 13B, 13C) placed on the substrate in the sealed space, a coil (112, 212) for transmitting or receiving alternating current power, the coil being placed in the sealed space on the magnetic plate in the stacking direction, a fluid substance having fluidity and enclosed in the sealed space, comprising a coil unit. (Form 2) The coil unit according to Form 1, wherein the fluid substance is a substance having a density greater than that of air under standard conditions, a coil unit. (Form 3) The coil unit according to Form 1 or Form 2, further comprising a partition plate (31, 31a, 31b, 31c, 31d) extending along the stacking direction in the sealed space, a coil unit. (Form 4) The coil unit according to Form 3, wherein the magnetic plate has a through-hole (41, 41a, 41b) through which the partition plate is inserted, The end of the partition plate is inserted into the through-hole and abuts against the substrate to divide the sealed space. Coil unit. (Embodiment 5) The coil unit according to Embodiment 4, wherein the coils are arranged concentrically and have a first coil (112a) and a second coil (112b) that are not electrically connected to each other, the through-holes (41a, 41b) are provided so as to correspond to a space formed in a radial gap between the first coil and the second coil, the partition plates (31a, 31b) are inserted into the through-holes through the radial gap between the first coil and the second coil and abut against the substrate. Coil unit. (Embodiment 6) The coil unit according to Embodiment 5, a first power transmission resonance circuit (110a) having the first coil and a first capacitor (116a), a second power transmission resonance circuit (116b) having the second coil and a second capacitor (116b), and the resonance frequency of the first power transmission resonance circuit and the resonance frequency of the second power transmission resonance circuit are the same as each other. Coil unit. (Embodiment 7) The coil unit according to any one of Embodiments 4 to 6, wherein the magnetic plate includes a protruding portion (51) that protrudes along the partition plate inserted into the through-hole on the surface on which the coil is placed. Coil unit. (Embodiment 8) The coil unit according to Embodiment 3, wherein the ends of the partition plates (31c, 31d) are separated along the stacking direction from at least one of the magnetic plate and the coil. Coil unit. (Embodiment 9) The coil unit according to any one of Embodiments 1 to 8, The cover (11D) is an inlet (61, 63) that communicates between the outside of the cover and the sealed space, and is an inlet for enclosing the fluid substance in the sealed space, an outlet (71, 73) that communicates between the outside of the cover and the sealed space, and is an outlet for discharging the air present in the sealed space when enclosing the fluid substance in the sealed space, and further includes the inner surface side of the cover has an inclination such that the dimension along the stacking direction of the sealed space increases from the inlet toward the outlet, coil unit.

Explanation of Signs

[0067] 10, 10A, 10B, 10C, 10D... coil units, 11, 11A, 11C, 11D... covers, 12... aluminum plates, 13, 13A, 13B, 13C... ferrite plates, 31, 31a, 31b, 31c, 31d... partition plates, 41, 41a, 41b... through holes, 51... protrusions, 112, 112a, 112b... power transmission coils, 212... power reception coils, 300... non-contact power supply system

Claims

1. A coil unit (10, 10A, 10B, 10C, 10D) used in a contactless power supply system (300), A substrate (12); a cover (11, 11A, 11C, 11D) that forms an enclosed space between the cover and the substrate; a magnetic plate (13, 13A, 13B, 13C) placed on the substrate in the sealed space; a coil (112, 212) for transmitting or receiving AC power, the coil being placed on the magnetic plate in a stacking direction within the sealed space; A fluid substance having fluidity that is sealed in the sealed space; Equipped with The flowable material is a dilatant fluid. Coil unit.

2. The coil unit according to claim 1, The flowable material is a material having a density greater than that of air under standard conditions. Coil unit.

3. The coil unit according to claim 1, Further provided are partition plates (31, 31a, 31b, 31c, 31d) extending along the stacking direction in the sealed space, Coil unit.

4. The coil unit according to claim 3, The magnetic plate has through-holes (41, 41a, 41b) through which the partition plate is inserted, an end of the partition plate is inserted through the through-hole and abuts against the base plate to divide the sealed space; Coil unit.

5. The coil unit according to claim 4, The coil includes a first coil (112a) and a second coil (112b) that are concentrically arranged and are not electrically connected to each other; the through-holes (41 a, 41 b) are provided to correspond to a space formed in a radial gap between the first coil and the second coil, the partition plates (31a, 31b) are inserted into the through-holes via a radial gap between the first coil and the second coil and come into contact with the substrate; Coil unit.

6. The coil unit according to claim 5, a first power transmitting resonant circuit (110a) having the first coil and a first capacitor (116a); a second power transmitting resonant circuit (116b) having the second coil and a second capacitor (116b); Equipped with a resonant frequency of the first power transmitting resonant circuit and a resonant frequency of the second power transmitting resonant circuit are identical to each other; Coil unit.

7. The coil unit according to any one of claims 4 to 6, The magnetic plate has a protrusion (51) on the surface on which the coil is placed that protrudes along the partition plate inserted into the through-hole. Coil unit.

8. The coil unit according to claim 3, The end of the partition plate (31c, 31d) is spaced apart from at least one of the magnetic plate and the coil along the stacking direction. Coil unit.

9. The coil unit according to any one of claims 1 to 6 and claim 8, The cover (11D) an inlet (61, 63) communicating the outside of the cover with the sealed space, the inlet being for injecting the fluid material into the sealed space; an outlet (71, 73) communicating the outside of the cover with the sealed space, the outlet being for discharging air present in the sealed space when the fluid material is sealed in the sealed space; Furthermore, The inner surface side of the cover has a slope such that the dimension of the sealed space along the stacking direction increases from the filling port toward the discharge port. Coil unit.

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