Wireless power receiving device, wireless power transmitting device, and wireless power transmission system

Abstract

To provide a wireless power receiving device, a wireless power transmission device, and a wireless power transmission system in which a housing for housing electrodes can be made thinner.SOLUTION: A wireless power transmission system 100 includes a wireless power transmission device 1 capable of transmitting electric power by an electric field coupling method, and a wireless power receiving device 2 capable of receiving power transmitted from the wireless power transmission device 1, and the wireless power transmission device 1 includes a power transmission side electrode 10, a power transmission side coil L1 electrically connected to the power transmission side electrode 10, a power transmission side first housing 110 that houses the power transmission side electrode 10, and a power transmission side second housing 120 that houses the power transmission side coil L1, and the wireless power receiving device 2 includes a power receiving side electrode 20, a power receiving side coil L2 electrically connected to the power receiving side electrode 20, a power receiving side first housing 130 that houses the power receiving side electrode 20, and a power receiving side second housing 140 that houses the power receiving side coil L2.SELECTED DRAWING: Figure 3

Description

[Technical field]

[0001] The present invention relates to a wireless power receiving device, a wireless power transmitting device, and a wireless power transmission system. [Background technology]

[0002] In recent years, with the spread of mobile phones, electric vehicles, etc., wireless power transmission systems that supply power wirelessly have been actively developed. For example, Patent Documents 1 to 3 describe wireless power transmission systems that include a wireless power transmitting device and a wireless power receiving device that have electrodes and coils housed in a housing. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] International Publication No. 2013 / 046366 [Patent Document 2] JP 2016-115789 A [Patent Document 3] Patent No. 5786949 Summary of the Invention [Problem to be solved by the invention]

[0004] In a wireless power transmission system using an electric field coupling method, the transmission efficiency improves if the area of ​​the electrodes is increased, but the housing that houses the electrodes becomes larger. For example, when this wireless power transmission system is applied to a device with limited space for installing the device or a mobile object such as an electric vehicle, it is desirable to make the housing that houses the electrodes smaller. The techniques of Patent Documents 1 to 3 have room for improvement in terms of making the housing that houses the electrodes thinner.

[0005] An object of the present invention is to provide a wireless power receiving device, a wireless power transmitting device, and a wireless power transmission system that can reduce the thickness of a housing that houses electrodes. [Means for solving the problem]

[0006] The present invention relates to a wireless power receiving device capable of receiving power using an electric field coupling method, comprising a power receiving electrode, a power receiving coil electrically connected to the power receiving electrode, a first power receiving housing that houses the power receiving electrode, and a second power receiving housing that houses the power receiving coil.

[0007] The second power-receiving housing may have higher electrical conductivity and thermal conductivity than the first power-receiving housing.

[0008] The power receiving side second housing is formed on a surface of the power receiving side first housing and has an insertion hole through which a transmission line connecting the power receiving side electrode and the power receiving side coil is inserted, and the peripheral portion of the insertion hole may be formed into a curved shape at least at both axial ends of the insertion hole.

[0009] The insertion hole may be formed to extend along the transmission line, and an axial length of the insertion hole may be longer than a thickness of a surface in which the insertion hole is formed.

[0010] The present invention also relates to a wireless power transmitting device capable of transmitting power by an electric field coupling method, comprising a power transmitting side electrode, a power transmitting side coil electrically connected to the power transmitting side electrode, a first power transmitting side housing that houses the power transmitting side electrode, and a second power transmitting side housing that houses the power transmitting side coil.

[0011] The power-transmitting-side second housing may have higher electrical conductivity and thermal conductivity than the power-transmitting-side first housing.

[0012] The power transmission side second housing is formed on a surface facing the power transmission side first housing and has an insertion hole through which a transmission line connecting the power transmission side electrode and the power transmission side coil is inserted, and the peripheral portion of the insertion hole may be formed into a curved shape at least at both axial ends of the insertion hole.

[0013] The insertion hole may be formed to extend along the transmission line, and an axial length of the insertion hole may be longer than a thickness of a surface in which the insertion hole is formed.

[0014] The present invention also relates to a wireless power transmission system comprising a wireless power transmitting device capable of transmitting power by an electric field coupling method, and a wireless power receiving device capable of receiving power transmitted from the wireless power transmitting device, wherein the wireless power transmitting device comprises a power transmitting side electrode, a power transmitting side coil electrically connected to the power transmitting side electrode, a first power transmitting side housing that houses the power transmitting side electrode, and a second power transmitting side housing that houses the power transmitting side coil, and the wireless power receiving device comprises a power receiving side electrode, a power receiving side coil electrically connected to the power receiving side electrode, a first power receiving side housing that houses the power receiving side electrode, and a second power receiving side housing that houses the power receiving side coil. Effect of the Invention

[0015] According to the present invention, it is possible to provide a wireless power receiving device, a wireless power transmitting device, and a wireless power transmission system that can reduce the thickness of a housing that houses electrodes. [Brief description of the drawings]

[0016] [Figure 1] 1 is a configuration diagram showing a wireless power transmission system according to an embodiment of the present invention. [Diagram 2] 1 is a schematic diagram of a circuit configuration of a wireless power transmission system according to an embodiment of the present invention. [Diagram 3] 2 is a cross-sectional view of a wireless power transmission system according to an embodiment of the present invention taken along the XZ plane shown in FIG. [Figure 4] 3 is an enlarged cross-sectional view of an insertion hole and its vicinity in a wireless power receiving device according to an embodiment of the present invention. FIG. [Diagram 5] 3 is an enlarged cross-sectional view of an insertion hole and its vicinity in a wireless power receiving device according to an embodiment of the present invention. FIG. [Figure 6] 11 is an enlarged cross-sectional view of an insertion hole and its vicinity in a first modified example of a wireless power receiving device according to an embodiment of the present invention. FIG. [Figure 7] 13 is an enlarged cross-sectional view of an insertion hole and its vicinity in a second modified example of a wireless power receiving device according to an embodiment of the present invention. FIG. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0017] (Embodiment) Hereinafter, a wireless power transmission system according to an embodiment of the present invention will be described. Note that the present invention is not limited to the following embodiment. Also, each drawing referred to in the following description merely shows a schematic shape, size, and positional relationship to the extent that the contents of the present invention can be understood. That is, the present invention is not limited to only the shape, size, and positional relationship exemplified in each drawing. Note that in the Cartesian coordinate system XYZ shown in the drawings, a direction parallel to the electrode plane is the X-axis direction, a direction in a plane perpendicular to the X-axis direction is the Y-axis direction, and a direction perpendicular to the electrode plane is the Z-axis direction.

[0018] First, the overall configuration of a wireless power transmission system 100 according to this embodiment will be described with reference to Fig. 1 and Fig. 2. Fig. 1 is a configuration diagram of the wireless power transmission system 100. Fig. 2 is a schematic diagram of the circuit configuration of the wireless power transmission system 100.

[0019] The wireless power transmission system 100 includes a wireless power transmitting device 1 and a wireless power receiving device 2. The wireless power transmission system 100 may be a system that transmits power in a state where the wireless power transmitting device 1 and the wireless power receiving device 2 are placed close to each other, or may be a slot-in type coupler that transmits power in a state where a pair of electrodes of an insertion side coupler is inserted between a pair of electrodes of a receiving side coupler. In this embodiment, a system in which the wireless power transmitting device 1 is provided on the ground of a parking space, the wireless power receiving device 2 is mounted on a mobile body such as an electric vehicle, and power is wirelessly transmitted to the mobile body parked in the parking space will be described as an example. In this embodiment, since the wireless power transmitting device 1 is provided on the ground and the wireless power receiving device 2 is mounted on a mobile body parked on the ground, the Z-axis direction is the up-down direction.

[0020] The wireless power transmitting device 1 will be described. The wireless power transmitting device 1 includes a power transmitting side electrode 10, a power transmitting side coil L1, transmission lines 31 to 34 which are a transmission line 30, a power source 3, a power transmitting side first housing 110, and a power transmitting side second housing 120. In Fig. 1, the power transmitting side first housing 110, the power transmitting side second housing 120, and the power receiving side first housing 130 and the power receiving side second housing 140 described below are indicated by dashed lines.

[0021] The power transmitter electrode 10 has a flat-plate-shaped first power transmitter electrode 11 and a flat-plate-shaped second power transmitter electrode 12. The first power transmitter electrode 11 and the second power transmitter electrode 12 are arranged on the same plane (on the XY plane in FIG. 1) with a gap between them.

[0022] The power transmitting side coil L1 is electrically connected to the power transmitting side electrode 10. The power transmitting side coil L1 has a first power transmitting side coil L11 and a second power transmitting side coil L12.

[0023] 1 and 2, the power transmitting side first coil L11 is connected to the power transmitting side first electrode 11 via a transmission line 31. That is, the transmission line 31 connects the power transmitting side first electrode 11 and the power transmitting side first coil L11.

[0024] 1 and 2, the second power transmitting coil L12 is connected to the second power transmitting electrode 12 via a transmission line 32. That is, the transmission line 32 connects the second power transmitting electrode 12 and the second power transmitting coil L12.

[0025] The power source 3 is an AC power source that supplies AC power to the power transmitting side coil L1 and the power transmitting side electrode 10. The power source 3 has terminals 4 and 5. As shown in FIG. 2, a transmission line 33 is connected to the terminal 4. A power transmitting side first coil L11 is connected to the end of the transmission line 33 opposite to the side to which the terminal 4 is connected. That is, as shown in FIG. 1 and FIG. 2, the power transmitting side first electrode 11 is connected to the power source 3 via the transmission line 31, the power transmitting side first coil L11, and the transmission line 33 in this order. On the other hand, a transmission line 32 is connected to the terminal 5. A power transmitting side second coil L12 is connected to the end of the transmission line 32 opposite to the side to which the terminal 5 is connected. That is, as shown in FIG. 1 and FIG. 2, the power transmitting side second electrode 12 is connected to the power source 3 via the transmission line 32, the power transmitting side second coil L12, and the transmission line 34 in this order. The power sent from the power source 3 is transmitted to the power transmitting electrode 10 via the transmission line 30 and the power transmitting coil L1.

[0026] The power transmitting side first housing 110 is box-shaped and houses the power transmitting side electrode 10. The power transmitting side second housing 120 is box-shaped and houses the power transmitting side coil L1 and the power source 3. The power transmitting side second housing 120 is disposed at a position adjacent to the power transmitting side first housing 110. In this embodiment, the power transmitting side first housing 110 and the power transmitting side second housing 120 are connected to each other. The configurations of the power transmitting side first housing 110 and the power transmitting side second housing 120 will be described later.

[0027] The wireless power receiving device 2 will be described. The wireless power receiving device 2 includes a power receiving electrode 20, a power receiving coil L2, transmission lines 41 to 44 that are the transmission line 40, a power receiving first housing 130, and a power receiving second housing 140, and is connected to a load 6. The load 6 is, for example, a storage battery, and is used in industrial equipment, portable electronic devices, and the like. Examples of the industrial equipment include electric vehicles, and examples of the portable electronic devices include laptop computers, smartphones, and portable music players.

[0028] The power receiving side electrode 20 has a flat plate-shaped power receiving side first electrode 21 and a flat plate-shaped power receiving side second electrode 22. The power receiving side first electrode 21 and the power receiving side second electrode 22 are arranged on the same plane (on the XY plane in FIG. 1) with a gap between them.

[0029] The power receiver coil L2 is electrically connected to the power receiver electrode 20. The power receiver coil L2 has a first power receiver coil L21 and a second power receiver coil L22.

[0030] 1 and 2, the power receiving side first coil L21 is connected to the power receiving side first electrode 21 via a transmission line 41. That is, the transmission line 41 connects the power receiving side first electrode 21 and the power receiving side first coil L21.

[0031] 1 and 2, the power receiving side second coil L22 is connected to the power receiving side second electrode 22 via a transmission line 42. That is, the transmission line 42 connects the power receiving side second electrode 22 and the power receiving side second coil L22.

[0032] The load 6 has terminals 7 and 8. As shown in FIG. 2, a transmission line 43 is connected to the terminal 7. A power receiving side first coil L21 is connected to the end of the transmission line 43 opposite to the end to which the terminal 7 is connected. That is, as shown in FIG. 1 and FIG. 2, the power receiving side first electrode 21 is connected to the load 6 via the transmission line 41, the power receiving side first coil L21, and the transmission line 43 in this order. On the other hand, a transmission line 44 is connected to the terminal 8. A power receiving side second coil L22 is connected to the end of the transmission line 44 opposite to the end to which the terminal 8 is connected. That is, as shown in FIG. 1 and FIG. 2, the power receiving side second electrode 22 is connected to the load 6 via the transmission line 42, the power receiving side second coil L22, and the transmission line 44 in this order.

[0033] The power receiving side first housing 130 is box-shaped and houses the power receiving side electrode 20. The power receiving side second housing 140 is box-shaped and houses the power receiving side coil L2 and the load 6. The power receiving side second housing 140 is disposed at a position adjacent to the power receiving side first housing 130. In this embodiment, the power receiving side first housing 130 and the power receiving side second housing 140 are connected to each other. The detailed configurations of the power receiving side first housing 130 and the power receiving side second housing 140 will be described later.

[0034] 1, by arranging the power transmitting electrode 10 and the power receiving electrode 20 facing each other with a gap therebetween, it becomes possible to transmit power from the wireless power transmitting device 1 to the wireless power receiving device 2 by electric field coupling. When transmitting power by this electric field coupling, the power transmitted to the power transmitting electrode 10 of the wireless power transmitting device 1 is transmitted to the power receiving electrode 20 of the wireless power receiving device 2. The power transmitted to the power receiving electrode 20 is transmitted to the load 6 via the transmission line 40 and the power receiving coil L2.

[0035] Next, details of power transmission by the electric field coupling method of the wireless power transmission system 100 will be described with reference to FIG.

[0036] When power is transmitted from the power source 3 with the power transmission side electrode 10 and the power receiving side electrode 20 facing each other, a capacitance C m1 is formed between the power transmitting side second electrode 12 and the power receiving side second electrode 22, and a capacitance Cm2 Since AC power is transmitted from the power source 3, the capacitance C m1 and capacity C m2 The electric charge is stored or discharged in the power transmitting electrode 1, whereby the electric power is transmitted from the wireless power transmitting device 1 to the wireless power receiving device 2, and the electric power is supplied to the load 6. Specifically, when a positive voltage is sent from the power source 3 and a positive electric charge from the power source 3 is accumulated in the power transmitting side first electrode 11, the capacitance C m1 A negative charge is induced in the power receiving side first electrode 21 via the power supply 3. Then, the negative voltage is transmitted to the wireless power receiving device 2. When a negative voltage is sent from the power supply 3 and a negative charge from the power supply 3 is accumulated in the power transmitting side first electrode 11, the capacitance C m1 A positive charge is induced in the power receiving side first electrode 21 via the power transmitting side coil L1, the power receiving side coil L2, the capacitance C m1 , capacity C m2 As described above, the power transmitted from the wireless power transmitting device 1 is a resonant circuit having a capacitance C m1 and capacity C m2 The power is transmitted to the wireless power receiving device 2 via the

[0037] Next, detailed configurations of the power receiving side first housing 130 and the power receiving side second housing 140 of the wireless power receiving device 2 and the power transmitting side first housing 110 and the power transmitting side second housing 120 of the wireless power transmitting device 1 will be described with reference to Fig. 1 and Fig. 3. Fig. 3 is a cross-sectional view of the wireless power transmission system 100 cut along the XZ plane shown in Fig. 1.

[0038] First, the configurations of the power receiving side first housing 130 and the power receiving side second housing 140 of the wireless power receiving device 2 will be described.

[0039] The wireless power receiving device 2 of this embodiment is disposed at the bottom of a moving body. Specifically, the power receiving side second housing 140 is located inside the moving body. On the other hand, the power receiving side first housing 130 has a capacitance Cm1 ,C m2 Since it is necessary to form the above, the movable body is located at or near the bottom of the movable body.

[0040] The power receiving side first housing 130 includes an electrode holding plate 131 that holds the power receiving side electrode 20, a first adjacent plate 132 that faces the electrode holding plate 131, and a side plate 133 that extends from the electrode holding plate 131 to the first adjacent plate 132. In an internal space 134 surrounded by the electrode holding plate 131, the first adjacent plate 132, and the side plate 133, the power receiving side first electrode 21, the power receiving side second electrode 22, and parts of the transmission lines 41 and 42 are arranged.

[0041] The electrode holding plate 131 is a surface that faces the first power transmitting electrode 11 and the second power transmitting electrode 12 when power is received from the wireless power transmitting device 1. As shown in Fig. 3, the first power receiving electrode 21 and the second power receiving electrode 22 are attached to the inner surface of the electrode holding plate 131 with a gap therebetween. The electrode holding plate 131 has a capacitance C m1 ,C m2 In order to form the power receiving side first housing 130, it is preferable that the power receiving side first housing 130 is made of insulating non-metal, etc. In this embodiment, the power receiving side first housing 130 is made of resin.

[0042] The first adjacent plate 132 is a surface adjacent to the power receiving side second housing 140. The first adjacent plate 132 is formed with insertion holes 71 and 72 which are the insertion hole 70 through which the transmission line 40 is inserted. Specifically, as shown in Fig. 3, the first adjacent plate 132 is formed with an interval between the insertion hole 71 through which the transmission line 41 is inserted and the insertion hole 72 through which the transmission line 42 is inserted.

[0043] The power receiving side second housing 140 includes a second adjacent plate 141 adjacent to the first adjacent plate 132, a top surface 142 facing the second adjacent plate 141, and a side plate 143 extending from the second adjacent plate 141 to the top surface 142. In an internal space 144 surrounded by the second adjacent plate 141, the top surface 142, and the side plate 143, the power receiving side coil L2, parts of the transmission lines 41 and 42, the transmission lines 43 and 44, and the load 6 are arranged.

[0044] The second adjacent plate 141 is connected to the first adjacent plate 132 of the power receiving side first housing 130. As shown in FIG. 3, the second adjacent plate 141 is formed with insertion holes 81 and 82, which are the insertion hole 80 through which the transmission line 40 is inserted. Specifically, as shown in FIG. 3, the second adjacent plate 141 is formed with the insertion hole 81 through which the transmission line 41 is inserted and the insertion hole 82 through which the transmission line 42 is inserted. The insertion hole 81 is formed at a position where its central axis approximately coincides with the central axis of the insertion hole 71. The insertion hole 82 is formed at a position where its central axis approximately coincides with the central axis of the insertion hole 72.

[0045] In this embodiment, the power receiving side electrode 20 and the power receiving side coil L2 that configure the electric circuit of the power receiving side electric field coupling method are housed in different housings. With this configuration, the thickness d1 of the power receiving side first housing 130 that houses the power receiving side electrode 20 that needs to face the power transmitting side electrode 10 during power supply can be made thinner.

[0046] Moreover, it is preferable that the power receiving side second housing 140 has higher electrical conductivity and thermal conductivity than the power receiving side first housing 130. The power receiving side second housing 140 of this embodiment is made of metal. The power receiving side second housing 140 of this embodiment is separate from the moving body and is disposed inside the moving body, but may be the moving body itself.

[0047] In this embodiment, the power receiving side second housing 140 that houses the power receiving side coil L2 is made of metal and has electrical conductivity, so that it can block noise generated from the power receiving side coil L2. In addition, the power receiving side second housing 140 has high thermal conductivity, so that it can release heat generated from the power receiving side coil L2 to the outside, and it is possible to suppress a decrease in transmission efficiency due to heat generation from the power receiving side coil L2 and deformation of the power receiving side second housing 140 itself.

[0048] Next, a detailed structure of the insertion hole 80 formed in the power receiving side second housing 140 will be described with reference to Fig. 4. Fig. 4 is an enlarged cross-sectional view of the insertion hole 80 of the wireless power receiving device 2 and its vicinity in an area A surrounded by a two-dot chain line shown in Fig. 3. Fig. 4 shows a state in which an AC current flows through the transmission line 41. Note that the insertion hole 81 and the insertion hole 82 of the insertion hole 80 have the same structure, so only the insertion hole 81 shown in Fig. 4 will be described and a description of the insertion hole 82 will be omitted.

[0049] 4, at least ends 812, 813, which are both ends of the insertion hole 81 in the axial direction DX, of the peripheral portion 811 of the insertion hole 81, are formed to have a curved surface. Specifically, in this embodiment, the insertion hole 81 is formed so as to increase in diameter toward both sides in the axial direction DX. In other words, the peripheral portion 811 of the insertion hole 81 formed in the second adjacent plate 141 is formed so as to move away from the central axis of the insertion hole 81 toward both sides in the axial direction DX.

[0050] Here, electric field concentration occurring at the periphery 811 of the insertion hole 81 when the power receiving side second housing 140 has high conductivity will be described. FIG. 5 is an enlarged cross-sectional view of an insertion hole 81' having a constant diameter in the axial direction DX and its vicinity. Ends 812', 813', which are both ends in the axial direction DX at the periphery 811' of the insertion hole 81' shown in FIG. 5, are formed at approximately right angles to the surface of the second adjacent plate 141' on the side of the internal space 144. When the power receiving side second housing 140' has high conductivity and the insertion hole 81' has the shape of FIG. 5, an electric field is likely to concentrate at the ends 812', 813' at the periphery 811' when a current flows through the transmission line 41.

[0051] In contrast, in this embodiment, ends 812, 813 of the peripheral portion 811 are formed in a curved shape as shown in Fig. 4. With this configuration, even if the power receiving side second housing 140 has high conductivity, it is possible to suppress electric field concentration occurring at the ends 812, 813 of the peripheral portion 811. Therefore, it is possible to suppress electric field concentration occurring at the insertion hole 80 for inserting the transmission line 40 into the power receiving side first housing 130 in which the power receiving side electrode 20 is accommodated, while shielding noise generated from the power receiving side coil L2 within the power receiving side second housing 140.

[0052] Next, a description will be given of the power transmitting side first housing 110 and the power transmitting side second housing 120 of the wireless power transmitting device 1. The wireless power transmitting device 1 of this embodiment is provided in a parking space of a mobile object. Specifically, the wireless power transmitting device 1 is installed on the ground of the parking space such that the power transmitting side first housing 110 is located above the power transmitting side second housing 120.

[0053] The power transmitting side first housing 110 includes an electrode holding plate 111 that holds the power transmitting side electrode 10, a first adjacent plate 112 that faces the electrode holding plate 111, and a side plate 113 that extends from the electrode holding plate 111 to the first adjacent plate 112. In an internal space 114 surrounded by the electrode holding plate 111, the first adjacent plate 112, and the side plate 113, the power transmitting side first electrode 11, the power transmitting side second electrode 12, and parts of the transmission lines 31 and 32 are arranged.

[0054] The electrode holding plate 111 is a surface that faces the first power receiving electrode 21 and the second power receiving electrode 22 when transmitting power to the wireless power receiving device 2. As shown in Fig. 3, the first power transmitting electrode 11 and the second power transmitting electrode 12 are attached to the inner surface of the electrode holding plate 111 with a gap therebetween. The electrode holding plate 111 has a capacitance C m1 , C m2 In order to form the insulating layer 110, it is preferable that the insulating layer 110 is made of an insulating nonmetallic material, etc. The power transmission side first casing 110 of this embodiment is made of resin.

[0055] The first adjacent plate 112 is a surface adjacent to the power transmission-side second housing 120. The first adjacent plate 112 is formed with insertion holes 51 and 52, which are the insertion hole 50 through which the transmission line 30 is inserted. Specifically, as shown in Fig. 3, the first adjacent plate 112 is formed with an interval between the insertion hole 51 through which the transmission line 31 is inserted and the insertion hole 52 through which the transmission line 32 is inserted.

[0056] The power transmission side second housing 120 includes a second adjacent plate 121 adjacent to the first adjacent plate 112, a bottom surface 122 facing the second adjacent plate 121, and a side plate 123 extending from the first adjacent plate 112 to the bottom surface 122. In an internal space 124 surrounded by the second adjacent plate 121, the bottom surface 122, and the side plate 123, the power transmission side coil L1, parts of the transmission lines 31 and 32, the transmission lines 33 and 34, and the power source 3 are arranged.

[0057] The second adjacent plate 121 is connected to the first adjacent plate 112 of the power transmission side first housing 110. As shown in FIG. 3, the second adjacent plate 121 is formed with insertion holes 61 and 62, which are the insertion hole 60 through which the transmission line 30 is inserted. Specifically, as shown in FIG. 3, the second adjacent plate 121 is formed with the insertion hole 61 through which the transmission line 31 is inserted and the insertion hole 62 through which the transmission line 32 is inserted. The insertion hole 61 is formed at a position where its central axis approximately coincides with the central axis of the insertion hole 51. The insertion hole 62 is formed at a position where its central axis approximately coincides with the central axis of the insertion hole 52. The structure of the insertion hole 60 is similar to the structure of the insertion hole 80 described above, and a description thereof will be omitted.

[0058] In this embodiment, the power transmitter electrode 10 and the power transmitter coil L1 that configure the electric circuit of the power transmitter electric field coupling type are housed in different housings. With this configuration, the thickness d2 of the power transmitter first housing 110 that houses the power transmitter electrode 10 that needs to face the power receiver electrode 20 during power supply can be made thinner.

[0059] Moreover, it is preferable that the power-transmitting-side second housing 120 has higher electrical conductivity and thermal conductivity than the power-transmitting-side first housing 110. The power-transmitting-side second housing 120 of this embodiment is made of metal.

[0060] In the above embodiment, the following modified example can be adopted for the configuration of the insertion hole 80 formed in the power receiving side second housing 140. The modified insertion hole configuration will be described while referring to the above description. In the following description, the configuration corresponding to that of the power receiving side second housing 140 is given the corresponding reference numerals with the same regularity. The description may be omitted or referred to. Also, the same configuration as the following modified example of the power receiving side second housing 140 can be applied to the configuration of the insertion hole 60 formed in the power transmitting side second housing 120.

[0061] First, the first modified example will be described with reference to Fig. 6. Fig. 6 is a cross-sectional view showing the insertion hole 80A of the power-receiving-side second casing 140A according to the first modified example and its vicinity.

[0062] The power-receiving-side second housing 140A differs from the power-receiving-side second housing 140 mainly in the configuration of the insertion hole 80A.

[0063] 6, the insertion hole 81A is formed in the second adjacent plate 141A, and the transmission line 40 is inserted through the insertion hole 81A. The length d4 of the insertion hole 81A in the axial direction DX is longer than the thickness d3 of the second adjacent plate 141A in which the insertion hole 80A is formed.

[0064] The insertion hole 81A is composed of a through hole 814 penetrating the second adjacent plate 141A, and cylindrical portions 815, 816 formed on both sides of the second adjacent plate 141A and extending from the periphery of the through hole 814 in a direction away from the second adjacent plate 141A. The cylindrical portions 815, 816 are formed so as to increase in diameter as they move away from the second adjacent plate 141A. For this reason, the peripheral portion 811A of the insertion hole 80A has end portions 812A, 813A, which are both ends in the axial direction DX, formed in a curved shape.

[0065] The insertion hole 80A of the first modified example may be formed, for example, by the following method. First, a through hole 814 is formed in the second adjacent plate 141A. Then, a tubular member having an inner diameter substantially equal to that of the through hole 814 is connected to both sides of the second adjacent plate 141A so as to be positioned coaxially with the through hole 814. Then, the end of the tubular member opposite the second adjacent plate 141A is bent in a direction in which the tubular member expands in diameter, thereby forming cylindrical portions 815, 816 whose diameter expands as they move away from the second adjacent plate 141A.

[0066] Next, a second modified example will be described with reference to Fig. 7. Fig. 7 is a cross-sectional view showing an insertion hole 80B of a power-receiving-side second casing 140B according to the second modified example and its vicinity.

[0067] The power-receiving-side second housing 140B differs from the power-receiving-side second housing 140 mainly in the configuration of the insertion hole 80B.

[0068] 7, the insertion hole 81B is formed in the second adjacent plate 141B, and the transmission line 40 is inserted therethrough. The insertion hole 81B is formed so as to extend along the transmission line 40. The length d4 of the insertion hole 81B in the axial direction DX is formed to be longer than the thickness d3 of the second adjacent plate 141B in which the insertion hole 81B is formed. In addition, the peripheral portion 811B of the insertion hole 81B has ends 812B, 813B, which are both ends in the axial direction DX, formed to have curved surfaces.

[0069] Specifically, the insertion hole 81B is composed of a through hole 814B that penetrates the second adjacent plate 141B, and cylindrical portions 815B, 816B that are formed on both sides of the second adjacent plate 141B and extend from the periphery of the through hole 814B in a direction away from the second adjacent plate 141B.

[0070] The cylindrical portions 815B, 816B have a constant diameter on the second adjacent plate 141B side, and on the opposite side of the second adjacent plate 141B in the axial direction DX, the diameter increases with increasing distance from the second adjacent plate 141B. That is, the insertion hole 81B has a constant diameter on the center side in the axial direction DX, and increases in diameter on both sides in the axial direction DX with increasing distance from the second adjacent plate 141B. Also, as shown in FIG. 7, the length d5 ​​in the axial direction DX of the range in which the diameter of the cylindrical portions 815, 816B on the second adjacent plate 141B side is constant is longer than the thickness d3 of the second adjacent plate 141B.

[0071] Since the insertion hole 81B is formed so as to extend along the transmission line 40 with a constant diameter longer than the thickness d3 of the second adjacent plate 141B in the axial direction DX, noise radiated from the transmission line 40 to the outside can be blocked.

[0072] According to this embodiment, the following effects are achieved.

[0073] The wireless power receiving device 2 of this embodiment comprises a power receiving electrode 20, a power receiving coil L2 electrically connected to the power receiving electrode 20, a power receiving first housing 130 that houses the power receiving electrode 20, and a power receiving second housing 140 that houses the power receiving coil L2, and is capable of receiving power using an electric field coupling method.

[0074] As a result, the power receiving electrode 20 and the power receiving coil L2 that configure the electric circuit of the power receiving side electric field coupling method are housed in different housings, so that the thickness d1 of the power receiving first housing 130 can be made thinner. For example, when the wireless power receiving device 2 is mounted on the bottom of a moving object as in the above embodiment, the power receiving first housing 130 that houses the power receiving electrode 20 that needs to face the power transmitting electrode 10 during power supply can be made thinner, so that a decrease in the ground clearance of the moving object can be suppressed.

[0075] Furthermore, in the wireless power receiving device 2 according to this embodiment, the power receiving second casing 140 has higher electrical conductivity and thermal conductivity than the power receiving first casing 130.

[0076] This allows the receiving coil L2 to be housed in a housing with higher electrical and thermal conductivity, thereby suppressing the decrease in transmission efficiency and deformation of the housing due to heat generation from the receiving coil L2, and also suppressing the leakage of noise generated from the receiving coil to the outside.

[0077] Furthermore, in the wireless power receiving device 2 of this embodiment, the power receiving side second housing 140 is formed on the second adjacent plate 141 on the power receiving side first housing 130 side, and has an insertion hole 80 through which the transmission lines 41, 42 connecting the power receiving side electrode 20 and the power receiving side coil L2 are inserted, and the peripheral portion 811 of the insertion hole 80 is formed in a curved shape at least at both ends 812, 813 in the axial direction DX of the insertion hole 80.

[0078] As a result, even if the power receiving side second housing 140 has high conductivity, the ends 812, 813 of the peripheral portion 811 of the insertion hole 80 through which the transmission lines 41, 42 are inserted are curved, so that electric field concentration occurring at both ends of the insertion hole can be suppressed.

[0079] In addition, in the wireless power receiving device 2 of this embodiment, the insertion hole 80 is formed to extend along the transmission lines 41, 42, and the length of the insertion hole 80 in the axial direction DX is longer than the thickness of the second adjacent plate 141 in which the insertion hole 80 is formed.

[0080] This makes it possible to suppress the external radiation of noise generated from the transmission line 40.

[0081] The wireless power transmission device 1 of this embodiment includes a power transmission side electrode 10, a power transmission side coil L1 electrically connected to the power transmission side electrode 10, a power transmission side first housing 110 that houses the power transmission side electrode 10, and a power transmission side second housing 120 that houses the power transmission side coil L1, and is capable of transmitting power using an electric field coupling method.

[0082] As a result, the power transmitting side electrode 10 and the power transmitting side coil L1 that configure the electric circuit of the power transmitting side electric field coupling method are housed in different housings, so that the thickness d2 of the power transmitting side first housing 110 can be made thinner. For example, when the wireless power transmitting device 1 is installed on the ground as in the above embodiment, the power transmitting side first housing 110 that houses the power transmitting side electrode 10 that needs to face the power receiving side electrode 20 during power supply can be made thinner, so that the height of the wireless power transmitting device 1 that protrudes from the ground can be reduced.

[0083] Furthermore, in the wireless power transmitting device 1 according to this embodiment, the power transmitting second casing 120 has higher electrical conductivity and thermal conductivity than the power transmitting first casing 110.

[0084] This allows the receiving coil to be housed in a housing with higher electrical and thermal conductivity, which prevents a decrease in transmission efficiency and deformation of the housing due to heat generation by the transmitting coil, and also prevents noise generated by the transmitting coil from leaking to the outside.

[0085] In addition, in the wireless power transmission device 1 of this embodiment, the power transmission side second housing 120 is formed on the second adjacent plate 121 on the power transmission side first housing 110 side, and has an insertion hole 60 through which the transmission line 30 connecting the power transmission side electrode 10 and the power transmission side coil L1 is inserted, and the peripheral portion of the insertion hole 60 is formed into a curved shape at least at both axial ends of the insertion hole 60.

[0086] As a result, even if the power transmission side second housing 120 is highly conductive, both axial ends of the peripheral portion of the insertion hole 60 through which the transmission lines 31, 32 are inserted are curved, so that electric field concentration occurring at both ends of the insertion hole 60 can be suppressed.

[0087] Furthermore, in the wireless power transmission device 1 according to this embodiment, the insertion hole 60 is formed to extend along the transmission line 30, and the length of the insertion hole 60 in the axial direction DX is longer than the thickness of the surface on which the insertion hole 60 is formed.

[0088] This makes it possible to suppress external radiation of noise generated from the transmission line 30.

[0089] The wireless power transmission system 100 of this embodiment includes a wireless power transmitting device 1 capable of transmitting power by an electric field coupling method, and a wireless power receiving device 2 capable of receiving power transmitted from the wireless power transmitting device 1. The wireless power transmitting device 1 includes a power transmitting side electrode 10, a power transmitting side coil L1 electrically connected to the power transmitting side electrode 10, a first power transmitting side housing 110 that houses the power transmitting side electrode 10, and a second power transmitting side housing 120 that houses the power transmitting side coil L1. The wireless power receiving device 2 includes a power receiving side electrode 20, a power receiving side coil L2 electrically connected to the power receiving side electrode 20, a first power receiving side housing 130 that houses the power receiving side electrode 20, and a second power receiving side housing 140 that houses the power receiving side coil L2.

[0090] This allows the power transmitting side first housing 110 that houses the power transmitting side electrode 10 and the power receiving side first housing 130 that houses the power receiving side electrode 20 to be made thinner.

[0091] Although the embodiment of the present invention has been described above, the present invention is not limited to this.

[0092] In the above embodiment, the power transmitter first housing 110 is made of resin, but only the electrode holding plate 111 that holds the power transmitter electrode 10 may be made of resin, with the other surfaces being made of metal. Similarly, the power receiver first housing 130 may also have only the electrode holding plate 131 that holds the power receiver electrode 20 made of resin, with the other surfaces being made of metal.

[0093] In the above embodiment, the power transmitting side second casing 120 and the power receiving side second casing 140 are made of metal, but they may be made of a non-metallic material such as resin.

[0094] In the above embodiment, the peripheral portion 811 of the insertion hole 80 and the peripheral portion of the insertion hole 60 are formed in a curved shape at least at both ends in the axial direction DX, but may be formed approximately perpendicular to the surface of the second adjacent plate 141 facing the internal space 144 in cross-sectional view, as in the peripheral portion 811' of the insertion hole 80' shown in Figure 5.

[0095] In the above embodiment, the power transmitting side first casing 110 and the power transmitting side second casing 120 or the power receiving side first casing 130 and the power receiving side second casing 140 are connected to each other, but they do not have to be connected to each other.

[0096] In the above embodiment, the power transmitting side first housing 110 and the power transmitting side second housing 120 or the power receiving side first housing 130 and the power receiving side second housing 140 are adjacent to each other, but they may also be arranged apart from each other and not adjacent to each other.

[0097] In the above embodiment, the power transmitting coil L1, the power receiving coil L2, and the capacitance C m1 , capacity C m2 However, they may be arranged to form a parallel resonant circuit. [Explanation of symbols]

[0098] 1 Wireless power transmission device 2. Wireless power receiving device 10 Power transmission electrode 20 Receiving electrode 100 Wireless power transmission system 110 Power transmission side first housing 120 Transmission side second housing 130 Receiving side first housing 140 Receiving side second housing L1 Power transmission coil L2 receiving coil

Claims

1. A power receiving electrode; a power receiving coil electrically connected to the power receiving electrode; a power-receiving-side first housing that accommodates the power-receiving-side electrode; a power receiving side second housing that houses the power receiving side coil, and the wireless power receiving device is capable of receiving power by an electric field coupling method.

2. The wireless power receiving device according to claim 1 , wherein the second power receiving housing has higher electrical conductivity and thermal conductivity than the first power receiving housing.

3. the power-receiving-side second housing includes an insertion hole through which a transmission line connecting the power-receiving-side electrode and the power-receiving-side coil is inserted, The wireless power receiving device according to claim 2 , wherein at least both axial ends of a peripheral portion of the insertion hole are curved.

4. the insertion hole is formed to extend along the transmission line, The wireless power receiving device according to claim 3 , wherein a length of the insertion hole in an axial direction is longer than a thickness of a surface on which the insertion hole is formed.

5. A power transmitting electrode; a power transmitting side coil electrically connected to the power transmitting side electrode; a power transmitter first housing that houses the power transmitter electrode; a power transmitting side second housing that houses the power transmitting side coil, and a wireless power transmitting device capable of transmitting power by an electric field coupling method.

6. The wireless power transmitting device according to claim 5 , wherein the second power transmitting case has higher electrical conductivity and thermal conductivity than the first power transmitting case.

7. the power transmitting side second housing includes an insertion hole through which a transmission line connecting the power transmitting side electrode and the power transmitting side coil is inserted, The wireless power transmitting device according to claim 6 , wherein at least both axial ends of a peripheral portion of the insertion hole are curved.

8. the insertion hole is formed to extend along the transmission line, The wireless power transmitting device according to claim 7 , wherein a length of the insertion hole in an axial direction is longer than a thickness of a surface in which the insertion hole is formed.

9. A wireless power transmission device capable of transmitting power by an electric field coupling method; a wireless power receiving device capable of receiving power transmitted from the wireless power transmitting device, The wireless power transmitting device includes: A power transmitting electrode; a power transmitting side coil electrically connected to the power transmitting side electrode; a power transmitter first housing that houses the power transmitter electrode; a power transmitting side second housing that accommodates the power transmitting side coil, The wireless power receiving device is A power receiving electrode; a power receiving coil electrically connected to the power receiving electrode; a power-receiving-side first housing that accommodates the power-receiving-side electrode; a power receiving side second housing that houses the power receiving side coil.

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