Coil unit

Abstract

To provide a coil unit that can absorb linear expansion shrinkage difference between a case body and a cover member, and improve waterproof performance.SOLUTION: A coil unit includes a coil 2 formed spirally, a wiring board 9 to which the coil is connected, a case body including a first housing space S1 that houses the coil and the wiring board, and a first cover member 5 that is attached to the case body and covers the first housing space. The case body includes wall parts 4A to 4G that form the first housing space, and a concave part formed on a surface of the wall part that faces the first cover member. The first cover member includes a convex part 54 formed on a surface of the first cover member that faces the wall part, and in a state where the convex part is inserted into the concave part filled with a seal material and the seal material exists between the first cover member and the wall part, the first cover member is attached to the case body.SELECTED DRAWING: Figure 4

Description

Technical Field

[0001] The present invention relates to a coil unit disposed on the ground or in an electric vehicle in a non-contact charging system for charging a battery mounted on the electric vehicle.

Background Art

[0002] In recent years, as a charging method for charging the in-vehicle battery of an electric vehicle, a non-contact charging system has attracted attention. In the non-contact charging system, electric power is transmitted between a power transmission side coil unit disposed on the ground and a power reception side coil unit disposed in the electric vehicle, and the battery mounted on the electric vehicle is charged.

[0003] Patent Document 1 discloses a coil unit (power supply coil unit) used in the above non-contact charging method. In this coil unit, a metal case is provided, and a control unit and a coil connected to the control unit are arranged side by side in the space inside the case. The opening of the case opens to the side facing the other coil unit, and the opening of the case is closed with a resin cover member so as to cover the coil inside the case.

Prior Art Documents

Patent Documents

[0004]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0005] In the technology described in the above Patent Document 1, in order not to interfere with the magnetic field of the coil, the opening of the metal case is closed with a resin cover member. However, when the case and the cover member are formed of different materials, their linear expansion coefficients are different values, so the linear expansion and contraction difference between the case and the cover member may increase depending on the environment where the coil unit is placed. When the linear expansion and contraction difference between the case and the cover member increases, the opening of the case opens, resulting in a problem that the waterproof performance of the coil unit deteriorates.

[0006] The present invention has been made to solve the above problems, and an object thereof is to provide a coil unit that can absorb the linear expansion and contraction difference between a case body and a cover member and improve the waterproof performance.

Means for Solving the Problems

[0007] The coil unit according to the first aspect of the present invention is a coil unit disposed on the ground or in an electric vehicle in a non-contact charging system that transmits power between a power transmission side coil unit disposed on the ground and a power reception side coil unit disposed in an electric vehicle and charges a battery mounted on the electric vehicle, and includes a coil formed in a spiral shape, a wiring board to which the coil is connected, a case body having an accommodation space for accommodating the coil and the wiring board, and a cover member attached to the case body to close the accommodation space. The case body has a wall portion that forms the accommodation space and a recess formed on a surface of the wall portion facing the cover member. The cover member has a convex portion formed on a surface of the cover member facing the wall portion. The cover member is attached to the case body with the convex portion inserted into the recess filled with a sealing material and the sealing material interposed between the cover member and the wall portion.

Effects of the Invention

[0008] According to the coil unit of the present invention, a coil and a wiring board are accommodated in the accommodation space of the case body, and the accommodation space is closed by a cover member attached to the case body. The case body has a recess formed on the surface facing the cover member in the wall portion forming the accommodation space, and the recess is filled with a sealing material. The cover member has a convex portion formed on the surface facing the wall portion of the accommodation space, and is attached to the case body with the convex portion inserted into the recess and the sealing material interposed therebetween and the wall portion. Therefore, even when the difference in linear expansion and contraction between the case body and the cover member increases according to the installation environment of the coil unit, the difference in linear expansion and contraction can be efficiently absorbed on the surfaces in a plurality of directions by deforming the sealing material interposed between the recess and the convex portion, so that the opening of the accommodation space can be prevented and the waterproof performance of the coil unit can be improved.

Brief Description of the Drawings

[0009]

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Mode for Carrying Out the Invention

[0010] Hereinafter, the non-contact charging system 100 according to the embodiment of the present invention and the coil unit 1 used in the non-contact charging system 100 will be described with reference to FIGS. 1 to 24. In the present embodiment, for convenience of explanation, the directions indicated by the arrows of up and down, left and right, and front and back appropriately shown in each figure are defined as the up and down direction, the left and right direction, and the front and back direction, respectively, and will be described. Also, in each figure, some reference numerals may be omitted for easy viewing of the drawing.

[0011] As shown in FIG. 24, the non-contact charging system 100 is a system for charging an electric vehicle 200 such as an electric vehicle or a plug-in hybrid vehicle. In the non-contact charging system 100, power is transmitted between a power transmission side coil unit 1A disposed on the ground and a power reception side coil unit 1B disposed on the electric vehicle 200, and the battery 300 mounted on the electric vehicle 200 is charged. The power transmission method is to arrange the primary coil 2 housed in the power transmission side coil unit 1A and the secondary coil 2 housed in the power reception side coil unit 1B to face each other, and use electromagnetic induction between the coils to transmit power. Specifically, by supplying alternating current power from an external power supply device 400 to the power transmission side coil unit 1A, an induced current flows through the primary coil 2 to generate a magnetic field. The generated magnetic field reaches the secondary coil 2, and power is transmitted when an induced current flows through the secondary coil 2.

[0012] Next, the coil units 1A and 1B constituting the non-contact charging system 100 having the above configuration will be described. Hereinafter, when the power reception side coil unit 1B is not distinguished from the power transmission side coil unit 1A, it will be simply described as the coil unit 1.

[0013] As shown in FIGS. 1 to 4, the coil unit 1 includes a box-shaped device case 3 that houses a coil 2 and the like to be described later. The device case 3 has a case body 4 in which accommodation spaces S1 and S2 for accommodating the coil 2 and the like are formed, and a first cover member 5 and a second cover member 6 that close the openings 41 and 42 of the case body 4.

[0014] As shown in FIGS. 5 to 8, the case body 4 has a predetermined width in the front-rear direction and the left-right direction, and is formed in a flat box shape in the up-down direction. The case body 4 is formed of a non-magnetic material such as aluminum, and as an example, it is made of aluminum die-cast. The case body 4 includes a front wall portion 4A, a rear wall portion 4B, a left wall portion 4C, a right wall portion 4D, an upper wall portion 4E, a bottom wall portion 4F, and a partition wall portion 4G. The partition wall portion 4G extends in the front-rear direction so as to connect the middle portion of the front wall portion 4A and the middle portion of the rear wall portion 4B. The upper wall portion 4E is integrally provided by connecting to the upper end portion of the partition wall portion 4G, the upper end portions of the front wall portion 4A and the rear wall portion 4B on the right side of the partition wall portion 4G, and the upper end portion of the right wall portion 4D. The bottom wall portion 4F is integrally provided by connecting to the lower end portion of the partition wall portion 4G, the lower end portions of the front wall portion 4A and the rear wall portion 4B on the left side of the partition wall portion 4G, and the lower end portion of the left wall portion 4C. In the case body 4, the upper and lower left and right cross-sections of the upper wall portion 4E, the partition wall portion 4G, and the bottom wall portion 4F are in a crank shape.

[0015] In such a case body 4, a first accommodation space S1 that opens downward is formed by the upper wall portion 4E, the partition wall portion 4G, the right wall portion 4D, the front wall portion 4A, and the rear wall portion 4B. Further, in the case body 4, a second accommodation space S2 that opens upward is formed by the bottom wall portion 4F, the partition wall portion 4G, the left wall portion 4C, the front wall portion 4A, and the rear wall portion 4B. In the case body 4, the internal space (accommodation space) of the case body 4 is partitioned into two left and right by the partition wall portion 4G, and the left and right internal spaces are open in the vertically opposite directions to each other.

[0016] In the case body 4, a coil case 7 that holds the coil 2 and the ferrite core 8 is accommodated in a first accommodation space S1 formed on the right side of the partition wall portion 4G (see FIG. 4). A wiring board 9 to which the coil 2 is connected is accommodated in a second accommodation space S2 formed on the left side of the partition wall portion 4G (see FIG. 4). Although not shown, a resonance circuit portion, a control portion, and a power conversion portion are mainly mounted on the wiring board 9. The resonance circuit portion includes a capacitor (resonance capacitor) connected in series or in parallel with the coil 2. The control portion monitors the charging power. The power conversion portion includes a rectification portion, and converts received high-frequency AC power into predetermined DC power and supplies it to a battery 300 mounted on the electric vehicle 200.

[0017] In the case body 4, the first accommodation space S1 formed on the right side of the partition wall portion 4G has a first opening 41 that opens downward. Further, the second accommodation space S2 formed on the left side of the partition wall portion 4G has a second opening 42 that opens upward. In the case body 4, the first opening 41 of the first accommodation space S1 and the second opening 42 of the second accommodation space S2 are separately provided on opposing side surfaces (4E, 4F) of the case body 4. Therefore, the case body 4 forms a crank-shaped structure having a stepped shape between the first accommodation space S1 and the second accommodation space S2 by the partition wall portion 4G.

[0018] Note that in FIGS. 1 to 23, since the power receiving side coil unit 1B mounted on the electric vehicle 200 is shown, the first accommodation space S1 opens downward so as to face the counterpart side (power transmission side) coil unit 1A installed on the ground. In the power transmission side coil unit 1A, the first accommodation space S1 opens upward so as to face the power receiving side coil unit 1B.

[0019] As shown in FIGS. 7 and 8, the first accommodation space S1 is a rectangular box-shaped accommodation space that opens downward in the device case 3, and side wall portions are formed by the front wall portion 4A, the rear wall portion 4B, the right wall portion 4D, and the partition wall portion 4G of the case body 4. A plurality of first boss portions 43 for fixing the first cover member 5 to the case body 4 are integrally formed on these wall portions 4A, 4B, 4D, 4G. The plurality of first boss portions 43 project from the wall portions 4A, 4B, 4D, 4G toward the inside of the first accommodation space S1, and are formed in a columnar shape with the vertical direction as the axial direction. The outer peripheral portion of the first cover member 5 is fixed to the case body 4 via the plurality of first boss portions 43.

[0020] As shown in FIGS. 9 to 11, the first cover member 5 is a resin plate-shaped member having a predetermined width in the front-rear direction and the left-right direction and a predetermined plate thickness in the vertical direction. The first cover member 5 is disposed below the case body 4 (see FIG. 4), and is configured to close the first opening 41 of the first accommodation space S1 by being attached to the case body 4. A plurality of first mounting holes 51 that penetrate the first cover member 5 in the vertical direction are formed in the outer peripheral portion of the first cover member 5. The plurality of first mounting holes 51 respectively correspond to the plurality of first boss portions 43 provided in the first accommodation space S1. The first cover member 5 is attached to the case body 4 by inserting a screw 52 (see FIGS. 2 and 3) into a screw hole (female screw) formed in the first mounting hole 51 and the first boss portion 43.

[0021] As shown in FIG. 11, on the lower surface 5B of the first cover member 5, a cover-side recess 53 is formed at a position corresponding to the first mounting hole 51. The cover-side recess 53 is a columnar recess that is recessed upward, and the first mounting hole 51 is formed in the bottom surface. A screw 52 inserted into the first mounting hole 51 from the outside of the first cover member 5 is inserted into the cover-side recess 53 so as not to protrude from the lower surface 5B of the first cover member 5. Therefore, in the power receiving coil unit 1B on the electric vehicle 200, the lower surface 5B of the first cover member 5 that constitutes the bottom surface of the electric vehicle 200 can be made flat, so that the aerodynamic performance of the lower part of the vehicle is not deteriorated. Further, it is possible to suppress contact between small stones rebounded from the road surface during traveling or obstacles that have entered the lower part of the vehicle and the screw 52.

[0022] In the device case 3, from the viewpoint of enhancing the sealing performance of the first accommodation space S1, a sealing material X is applied to the opposing surfaces of the wall portions 4A, 4B, 4D, 4G that constitute the side wall portion of the first accommodation space S1 in the case body 4 and the first cover member 5. As shown in FIGS. 7 and 8, recesses 44 are formed in the lower end surfaces (the surfaces to which the sealing material X is applied) of the wall portions 4A, 4B, 4D, 4G that constitute the side wall portion of the first accommodation space S1 in the case body 4. The recesses 44 are arranged inside the first boss portion 43 in the wall portions 4A, 4B, 4D, 4G and are formed linearly extending along the outer peripheral portion of the first opening 41. As shown in FIG. 20, the recesses 44 are formed in a rectangular groove shape that opens to the first cover member 5 side (lower side), and have a pair of opposing side surfaces 441 and a bottom surface 442 that connects the upper ends of the pair of side surfaces 441.

[0023] As shown in FIGS. 9 and 10, convex portions 54 are formed on the peripheral edge portion (the portion to which the sealing material X is applied) of the upper surface 5A of the first cover member 5. The convex portions 54 are arranged inside the first mounting hole 51 at the peripheral edge portion of the upper surface 5A of the first cover member 5 and are configured as linear convex portions that extend along the peripheral edge portion of the upper surface 5A. As shown in FIG. 20, the convex portions 54 stand upright from the upper surface 5A of the first cover member 5 toward the case body 4 side (upper side), and the cross section in the direction orthogonal to the extending direction forms a rectangular shape that is slightly smaller than the recess 44.

[0024] When attaching the first cover member 5 to the case body 4, after filling the recess 44 of the case body 4 with the sealing material X, the first cover member 5 is attached to the case body 4 such that the convex portion 54 of the first cover member 5 is inserted into the recess 44 of the case body 4. When the first cover member 5 is attached to the case body 4 in this way, as shown in Fig. 20, a part of the sealing material X in the recess 44 is pressed against the convex portion 54 and pushed out from the recess 44, and the sealing material X is interposed between the lower end surfaces of the wall portions 4A, 4B, 4D, 4G of the case body 4 and the upper surface 5A of the first cover member 5. A part of the sealing material X also remains in the recess 44, and the sealing material X is interposed between the pair of side surfaces 441 and the bottom surface 442 constituting the recess 44 and the respective surfaces constituting the convex portion 54. The sealing material X is, for example, composed of a silicon-based wet sealing material, is filled in the recess 44 in a liquid state, and when cured, becomes a rubbery material with elasticity.

[0025] For the configuration of inserting the convex portion 54 of the first cover member 5 into the recess 44 formed on the case body 4 side as described above, there are mainly two reasons. The first reason is to increase the area of the joint portion between the case body 4 and the first cover member 5 and enhance the joint strength between the case body 4 and the first cover member 5 by the sealing material X. Thereby, when the difference in linear expansion and contraction between the metal case body 4 and the resin first cover member 5 becomes large, even if a part of the first cover member 5 deviates from the case body 4, it is possible to suppress the opening of the first accommodation space S1. The second reason is that by interposing the elastic sealing material X between the recess 44 and the convex portion 54, the difference in linear expansion and contraction between the case body 4 and the resin first cover member 5 can be efficiently absorbed in multiple directions by the elastic deformation of the sealing material X.

[0026] Specifically, the second reason will be described. For example, when the vehicle is cooled in a cold region, the resin-made first cover member 5 with a large coefficient of linear expansion shrinks more than the metal-made case body 4. Therefore, an external force may act on the first cover member 5 in a direction to separate the first cover member 5 from the first opening 41 of the case body 4. At this time, since the sealing material X near the side surface 441 of the concave portion 44 elastically deforms following the side surface of the convex portion 54 of the first cover member 5, it is possible to absorb the difference in linear expansion and contraction while maintaining the sealing performance between the case body 4 and the first cover member 5. On the other hand, for example, when the vehicle is hot immediately after driving, the resin-made first cover member 5 expands more than the metal-made case body 4. Therefore, the separation distance t1 from the side surface of the concave portion 44 may become small on one side surface of the convex portion 54 in the first cover member 5. Since the sealing material X near the side surface 441 of the concave portion 44 elastically deforms so as to be pushed out toward the bottom surface 442 side of the concave portion 44, it is possible to absorb the difference in linear expansion and contraction while maintaining the sealing performance between the case body 4 and the first cover member 5.

[0027] As shown in Fig. 20, in a state where the first cover member 5 is attached to the case body 4, the separation distance t2 between the tip of the convex portion 54 and the bottom surface 442 of the concave portion 44 is set to be larger than the separation distance t1 between the side surface of the convex portion 54 and the side surface of the concave portion 44. This configuration aims to efficiently absorb the difference in expansion and contraction between the case body 4 and the first cover member 5. That is, as described above, it is assumed that the relative positional relationship between the side surface of the convex portion 54 of the first cover member 5 and the side surface 441 of the concave portion 44 will change significantly as the difference in linear expansion and contraction between the case body 4 and the first cover member 5 increases. If the positional relationship between the side surface of the convex portion 54 and the side surface 441 of the concave portion 44 changes significantly, there is a risk that the difference in expansion and contraction cannot be fully absorbed in the spaces on both sides of the side surface of the convex portion 54. Therefore, by increasing the separation distance t2 between the tip of the convex portion 54 and the bottom surface 442 of the concave portion 44, the seal layer on the bottom surface 442 side of the concave portion 44 that communicates with the spaces on both sides of the side surface of the convex portion 54 is thickened. When the seal layer on the bottom surface 442 side of the concave portion 44 is thickened, even when the difference in expansion and contraction cannot be fully absorbed in the spaces on both sides of the side surface of the convex portion 54, the sealing material X can be efficiently deformed, so that the difference in expansion and contraction between the case body 4 and the first cover member 5 can be efficiently absorbed.

[0028] Furthermore, on the wall portions 4A, 4B, 4D, 4G that form the first accommodation space S1 in the case body 4, inclined surfaces 45 are formed by chamfering the corners on the first accommodation space S1 side. This configuration aims to enhance the airtightness of the first accommodation space S1. The inclined surfaces 45 are inclined so that the gap between the inclined surfaces 45 and the opposing surface (upper surface 5A) of the first cover member 5 increases as it goes toward the inside of the first accommodation space S1. Therefore, when the liquid sealing material X is filled in the concave portion 44 and the first cover member 5 is attached to the case body 4, the sealing material X extruded from the inside of the concave portion 44 toward the first accommodation space S1 side by the convex portion 54 stays between the inclined surface 45 and the upper surface 5A of the first cover member 5, forming a seal layer with a certain thickness. Thereby, the airtightness of the first accommodation space S1 can be enhanced. Also, by retaining the excess portion of the sealing material X between the inclined surface 45 and the first cover member 5, it prevents the sealing material X from flowing into the first accommodation space S1.

[0029] As shown in FIGS. 7 and 8, on the lower surface of the upper wall portion 4E of the case body 4, a central boss portion 47 protruding downward is disposed at the center of the first accommodation space S1. The central boss portion 47 (first support portion) is formed in a columnar shape with the vertical direction as the axial direction, and the central portion of the first cover member 5 is fixed to the case body 4 via the central boss portion 47. As shown in FIG. 21, a recessed portion 46 recessed upward is formed at the center of the lower surface of the central boss portion 47. Due to the recessed portion 46, the lower end portion of the central boss portion 47 is formed in a cylindrical shape. Further, a female screw hole is formed at the center of the recessed portion 46. In a state where the first cover member 5 is attached to the case body 4, the lower end surface of the central boss portion 47 abuts against the opposing surface (upper surface 5A) of the first cover member 5 to support the first cover member 5 from the inside of the first accommodation space S1. An annular recess 471 is formed on the lower end surface (the surface facing the first cover member 5) of the central boss portion 47. This recess 471 is formed in a rectangular groove shape opening toward the first cover member 5 side (lower side), and a sealing material X is filled inside the recess 471.

[0030] As shown in FIGS. 9 and 10, on the upper surface 5A of the first cover member 5, a cylindrical protrusion 59 is formed at a position facing the central boss portion 47 (the central position of the upper surface 5A). A screw hole 55 penetrating in the vertical direction is formed at the center of the protrusion 59. As shown in FIG. 21, the protrusion 59 of the first cover member 5 is inserted into the recessed portion 46 of the central boss portion 47 of the case body 4, and a screw 52 inserted through the screw hole 55 is screwed into the female screw hole of the recessed portion 46, whereby the first cover member 5 is fixed to the case body 4. A cover-side recess 53 is formed on the lower surface 5B of the first cover member 5 at a position corresponding to the protrusion 59 and the screw hole 55. Since the cover-side recess 53 has the same configuration as the cover-side recess 53 provided corresponding to the first mounting hole 51 in the first cover member 5, the description thereof is omitted. The screw 52 inserted into the screw hole 55 from the outside of the first cover member 5 is inserted into the cover-side recess 53 so as not to protrude from the lower surface 5B of the first cover member 5.

[0031] As shown in FIGS. 9 and 10, an annular convex portion 56 is integrally formed on the upper surface 5A of the first cover member 5 so as to surround the protruding portion 59. As shown in FIG. 21, the convex portion 56 stands upright upward from the upper surface 5A of the first cover member 5, and has a rectangular cross-section in a direction orthogonal to the extending direction. The first cover member 5 is attached to the case body 4 by inserting the convex portion 56 into the concave portion 471 of the case body 4 (central boss portion 47) filled with the sealing material X and interposing the sealing material X between the upper surface 5A of the first cover member 5 and the lower end surface of the central boss portion 47. When the first cover member 5 is attached to the case body 4 in this way, a part of the sealing material X in the concave portion 471 is pressed against the convex portion 56 and extruded from the concave portion 471, and the sealing material X is interposed between the lower end surface of the central boss portion 47 and the upper surface 5A of the first cover member 5. A part of the sealing material X also remains in the concave portion 471, and the sealing material X is interposed between the surfaces constituting the concave portion 471 and the surfaces constituting the convex portion 56. Thereby, the case body 4 and the first cover member 5 can be brought into close contact with each other via the sealing material X to ensure the airtightness of the first accommodation space S1, and furthermore, the difference in linear expansion and contraction between the case body 4 and the first cover member 5 can be absorbed.

[0032] As shown in FIGS. 9 and 10, on the upper surface 5A of the first cover member 5, a cylindrical second support portion 57 protruding upward is formed at a position radially outside the annular convex portion 56. The second support portion 57 stands upright upward from the upper surface 5A of the first cover member 5 and is formed in a cylindrical shape centered on the screw hole 55, and an inner wall 571 and an outer wall 572 are formed. The inner wall 571 stands upright upward from the upper surface 5A, and the outer wall 572 stands upright upward from the upper surface 5A outside the inner wall 571 in the radial direction, constituting a double-cylindrical shape. Between the inner wall 571 and the outer wall 572, a plurality of ribs 573 are connected to form a lattice shape when viewed from the axial direction. As shown in FIG. 21, in a state where the first cover member 5 is attached to the case body 4, the second support portion 57 is arranged in a nested manner with the central boss portion 47 (first support portion) of the case body 4 entering the inside. At this time, the upper end portion of the second support portion 57 abuts against the opposing surface (the lower surface of the upper wall portion 4E) of the case body 4, and the case body 4 is configured to be supported from the inside of the first accommodation space S1. The centrally disposed boss portion 47 and the second support portion 57 arranged in a nested manner are disposed within the central space of the coil 2 in a state where the coil 2 is accommodated in the first accommodation space S1.

[0033] As described above, the coil 2 is held by the coil case 7 and accommodated in the first accommodation space S1 of the case body 4. As shown in FIGS. 14 to 17, the coil case 7 is a resin plate-like member having a predetermined width in the front-rear direction and the left-right direction and a predetermined thickness in the vertical direction, and is formed in a rectangular shape when viewed from the vertical direction. A rectangular opening 71 penetrating the coil case 7 in the vertical direction is formed in the central portion of the coil case 7. In a state where the coil case 7 is accommodated in the first accommodation space S1, the central boss portion 47 of the case body 4 and the second support portion 57 of the first cover member 5 are disposed inside the opening 71. The upper surface side of the coil case 7 is a core fixing surface 7A to which a plurality of ferrite cores 8 are fixed. Rectangular plate-like ferrite cores 8 are fixed to each of the compartments partitioned in a grid pattern by a plurality of partition wall portions 72 on the core fixing surface 7A.

[0034] Outside the opening 71 of the coil case 7, a coil insertion hole 73 penetrating the coil case 7 in the vertical direction is formed. One end 2A (see FIG. 4) of the coil 2 held on the lower surface side of the coil case 7 is inserted into the coil insertion hole 73 and drawn out to the core fixing surface 7A side of the coil case 7. One end 2A of the coil 2 drawn out to the core fixing surface 7A side is inserted into and held by a groove-shaped first coil guide portion 74A provided on the left end portion side of the core fixing surface 7A in the coil case 7.

[0035] The lower surface side of the coil case 7 serves as a coil fixing surface 7B for fixing the coil 2. A coil accommodation groove 76 formed in a spiral shape is formed in the coil fixing surface 7B. The coil accommodation groove 76 is, as an example, in the shape of a rectangular groove opening downward, and the wire rod forming the coil 2 is inserted inside. In the present embodiment, the coil 2 is composed of a Litz wire 21 in order to prevent an increase in winding resistance due to the skin effect. The Litz wire 21 is formed by twisting a plurality of insulated wire rods (fine wires), and forms a spiral-shaped coil 2 by being inserted into the coil accommodation groove 76 of the coil case 7. In this way, a spiral coil 2 is arranged on the coil fixing surface 7B (on the surface) of the coil case 7. Both ends 2A, 2A of the coil 2 are drawn out to the upper core fixing surface 7A through the coil insertion hole 73 with one end 2A arranged on the central space side of the coil 2. On the other hand, in the coil 2, the other end 2A arranged on the radially outer side is inserted into and held by a second coil guide portion 74B extended from the end of the coil accommodation groove 76 to the left end portion side of the coil fixing surface 7B.

[0036] A plurality of coil case side boss portions 75 are integrally formed on the outer peripheral portion of the coil case 7 and the inner surface of the opening 71. The coil case 7 is fixed to the upper wall portion 4E of the case body 4 via the plurality of coil case side boss portions 75. A case body side boss portion 48 is provided at a position facing the coil case side boss portion 75 of the coil case 7 on the upper wall portion 4E (see FIG. 8). The coil case 7 is fixed in the first accommodation space S1 of the case body 4 by inserting screws (not shown) through the coil case side boss portion 75 and the case body side boss portion 48.

[0037] As schematically shown in FIG. 8, in the coil case 7 fixed within the first accommodation space S1 of the case body 4, both end portions 2A, 2A of the coil 2 held by the first coil guide portion 74A and the second coil guide portion 74B extend toward the partition wall portion 4G that constitutes the left side wall portion of the first accommodation space S1, and are guided into the second accommodation space S2 through the insertion hole 49 formed in the partition wall portion 4G. Both end portions 2A, 2A of the coil 2 guided into the second accommodation space S2 are connected to the mounting surface 9A on the upper surface of the wiring board 9 accommodated in the second accommodation space S2 via terminal members 22 (see FIG. 18). The detailed configuration of the terminal members 22 will be described later.

[0038] The insertion hole 49 is formed across the partition wall portion 4G and the bottom wall portion 4F of the case body 4, penetrates the partition wall portion 4G in the left-right direction to communicate the first accommodation space S1 and the second accommodation space S2, and penetrates the bottom wall portion 4F in the up-down direction to communicate the second accommodation space S2 and the outside. The insertion hole 49 is disposed inside the recess 44 that extends along the first opening portion 41 of the case body 4. Therefore, in a state where the first cover member 5 is attached to the case body 4, since the periphery of the insertion hole 49 is sealed with the sealing material X, it is prevented that water droplets or the like enter the inside through the insertion hole 49 from the outside of the device case 3.

[0039] As described above, the case body 4 is die-cast. Since the insertion hole 49 has a portion that opens in the vertical direction, it can be formed by a die-casting mold composed only of upper and lower molds. Therefore, since a mold that requires lateral insertion and extraction is not required, the configuration of the mold can be simplified. When the first cover member 5 is attached to the case body 4, the lower side of the insertion hole 49 is blocked by a protruding portion 58 protruding from the left end portion 5L of the first cover member 5 (see FIGS. 10 and 2). A stepped portion 4H is formed on the surface of the bottom wall portion 4F along the shape of the left end portion 5L of the first cover member 5. When the left end portion 5L of the first cover member 5 is overlapped on the lower surface side of the partition wall portion 4G, it is fitted into the stepped portion 4H of the bottom wall portion 4F to position the first cover member 5, and the lower surface of the bottom wall portion 4F and the lower surface 5B of the first cover member 5 are flush.

[0040] Next, with reference to FIGS. 18 and 19, the connection structure between the litz wire 21 and the wiring board 9 at both ends 2A, 2A of the coil 2 will be described. In the present embodiment, the end of the litz wire 21 is connected to the wiring board 9 via a terminal member 22.

[0041] By the way, conventionally, as a method of fixing the end of a litz wire to a wiring board, a method of fixing by crimping (riveting) the end of the litz wire to one end of a terminal member screwed to the wiring board is known. In such crimping of the terminal member and the litz wire, in a litz wire formed by twisting a plurality of wire rods, the crimping portions of each wire rod and the terminal member 22 become unstable, resulting in a problem of power loss due to contact resistance. In addition, the contact resistance between the terminal member, the wiring board, and the fixing screw is also significant, which also causes power loss.

[0042] As shown in FIG. 18, the terminal member 22 is composed of a metal plate-like member, and includes a board fixing portion 23 fixed to the wiring board 9 and a clamping portion 24 formed integrally with the board fixing portion 23 for clamping the end portion of the litz wire 21. The board fixing portion 23 is composed of a long plate-like member having a predetermined plate thickness in the vertical direction, and the lower surface side thereof is placed on the mounting surface 9A of the upper surface of the wiring board 9. On the upper surface side of the board fixing portion 23, the end portion of the litz wire 21 is placed in a posture where the longitudinal direction of the board fixing portion 23 is the extending direction of the litz wire 21. The board fixing portion 23 is formed with a pair of leg portions 231 extending toward the wiring board 9 at each of one end and the other end in the longitudinal direction. The pair of leg portions 231 are inserted into through holes 91 penetrating the wiring board 9 in the vertical direction and soldered to be mounted on the wiring board 9.

[0043] The clamping portion 24 has a pair of arm portions 241 integrally formed on both sides in the short side direction of the substrate fixing portion 23. The pair of arm portions 241 extend from the substrate fixing portion 23 to the side opposite to the leg portion 231 (upper side), and are disposed on both sides of the litz wire 21 placed on the substrate fixing portion 23. The base end portions of the pair of arm portions 241 protruding from the substrate fixing portion 23 extend along the circumferential direction of the litz wire 21, and the tip portions are bent in a direction away from each other to form tapered introduction portions 241A that spread out. The end portion of the litz wire 21 is previously immersed in the solder Y melted in the preliminary soldering process so that the solder Y penetrates between the wire materials, and is then attached to the terminal member 22 (see FIG. 19). At this time, the end portion of the litz wire 21 is inserted between the introduction portions 241A, and the pair of arm portions 241 are elastically deformed so as to push open the introduction portions 241A and are inserted inside the pair of arm portions 241. When the litz wire 21 passes through the introduction portion 241A, the pair of arm portions 241 that have been pushed open are restored to their original positions to clamp the end portion of the litz wire 21. In the present embodiment, a pair of clamping portions 24 are provided at two locations along the longitudinal direction of the substrate fixing portion 23, but the number of the pair of arm portions 241 can be appropriately changed, and it may be one or three or more. The terminal member 22 attaches the solder Y so as to cover the end portion of the litz wire 21 covered with the solder Y by the preliminary soldering process by the pair of arm portions 241, thereby connecting the end portion of the litz wire 21 to the wiring board 9.

[0044] What is remarkable in the above configuration is that, firstly, by clamping the end portion of the litz wire 21 impregnated with the solder Y by the pair of arm portions 241 (clamping portion 24) of the terminal member 22, the contact portion between the terminal member 22 and the litz wire 21 is stabilized. Since each wire material constituting the litz wire 21 is clamped by the pair of arm portions 241 in a state of being covered with the solder Y in the preliminary soldering process, each wire material of the litz wire 21 does not directly contact the pair of arm portions 241, and each wire material of the litz wire 21 is clamped with the solder Y by the preliminary soldering process interposed between the pair of arm portions 241. As a result, the contact resistance between the litz wire 21 and the terminal member 22 is reduced, and power loss can be reduced.

[0045] Second, by attaching solder Y so as to cover the end of the litz wire 21 and the clamping portion 24, it is possible to surely interpose the solder Y between the litz wire 21 and the terminal member 22. As a result, since it is possible to realize a connection state similar to directly soldering the end of the litz wire 21 (each wire) to the wiring board 9, it is possible to improve the mechanical bonding strength between the litz wire 21 and the terminal member 22, and to further stabilize the contact between the litz wire 21 and the terminal member 22 (wiring board 9) and reduce the contact resistance. Further, since the litz wire 21 is clamped by the terminal member 22, it is possible to reduce the stress on the solder due to the vibration and impact of the vehicle.

[0046] Hereinafter, with reference to FIGS. 5 and 6, the second accommodation space S2 of the case body 4 will be described. The second accommodation space S2 is a rectangular box-shaped accommodation space that opens upward of the case body 4, and side wall portions are formed by the front wall portion 4A, the rear wall portion 4B, the left wall portion 4C, and the partition wall portion 4G of the case body 4. A plurality of second boss portions 50 for fixing the second cover member 6 to the case body 4 are integrally formed on these wall portions 4A, 4B, 4C, 4G. The second accommodation space S2 houses a wiring board 9 and a resonance choke (not shown) for optimizing the transmission efficiency. Two connector mounting portions 501 and 502 are formed on the left wall portion 4C that constitutes the left side wall portion of the second accommodation space S2. The connector mounting portions 501 and 502 are formed in a cylindrical shape protruding from the left wall portion 4C to the outside of the case body 4, and the housing 11A of the input-side connector 11 and the housing 12A of the output-side connector 12 are mounted inside (see FIG. 1). Connection terminals (not shown) are provided on the housings 11A and 12A, respectively, and the connection terminals are connected to the mounting surface 9A of the wiring board 9. The input-side connector 11 is connected to a cable connector that is electrically connected to a power source (not shown) or the like. The output-side connector 12 is connected to a cable connector that is electrically connected to the battery 300 of the electric vehicle 200, and supplies the power received by the coil 2 to the battery 300 of the electric vehicle 200.

[0047] As shown in FIGS. 12 and 13, the second cover member 6 is a plate-shaped member made of metal having a predetermined width in the front-rear direction and the left-right direction and a predetermined plate thickness in the up-down direction. The second cover member 6 is disposed above the case body 4 and is configured to close the second opening 42 of the second accommodation space S2 by being attached to the case body 4. A plurality of second attachment holes 61 penetrating the second cover member 6 in the up-down direction are formed in the outer peripheral portion of the second cover member 6. Each of the plurality of second attachment holes 61 corresponds to a plurality of second boss portions 50 provided on each wall portion forming the second accommodation space S2. The second cover member 6 is attached to the case body 4 by inserting screws 62 into the second attachment holes 61 and the second boss portions 50.

[0048] On the lower surface side of the second cover member 6, a housing recess 63 is formed by press-molding to project the upper surface of the second cover member 6 upward. The housing recess 63 is a rectangular box-shaped housing space opened downward, and houses various circuit elements such as capacitors mounted on the wiring board 9 and resonance chokes for optimizing transmission efficiency.

[0049] A point worthy of note regarding this second accommodation space S2 is at the fixed position on the right end portion 6R side of the second cover member 6. As described above, in the case body 4, a first boss portion 43 for attaching the first cover member 5 to the case body 4 and a second boss portion 50 for attaching the second cover member 6 to the case body 4 are integrally formed on the partition wall portion 4G partitioning the first accommodation space S1 and the second accommodation space S2. Therefore, as shown in FIG. 3, the right end portion 6R side (position end portion side) of the second cover member 6 is disposed so as to cover the upper surface side of the partition wall portion 4G, and the left end portion 5L side of the first cover member 5 and the right end portion 6R side of the second cover member 6 are attached to the case body 4 in a state of overlapping vertically with the partition wall portion 4G interposed therebetween.

[0050] (Operation and Effect) As described above, in the coil unit 1 of the present embodiment, the coil 2 and the wiring board 9 connected to the coil 2 are housed inside the device case 3. The case main body 4 of this device case 3 has a first accommodation space S1 and a second accommodation space S2 partitioned by a partition wall portion 4G. The coil 2 is housed in the first accommodation space S1, and the wiring board 9 is housed in the second accommodation space S2. The case main body 4 has an opening in a direction in which the first accommodation space S1 faces the coil unit on the other side, and the second accommodation space S2 has an opening on the side opposite to the first accommodation space. Therefore, the case main body 4 is formed in a crank shape having a stepped shape between the first accommodation space S1 and the second accommodation space S2 by the partition wall portion 4G, and the strength of the case main body 4 can be improved by increasing the rigidity of the cross section. Furthermore, since the first opening 41 of the first accommodation space S1 in which the coil 2 is housed becomes smaller and the first cover member 5 can be downsized, the strength of the entire device case 3 can also be increased in this way. In this manner, in the coil unit 1 according to the present invention, the strength of the device case 3 can be improved.

[0051] Also, in the present embodiment, a first boss portion 43 for fixing the first cover member 5 and a second boss portion 50 for fixing the second cover member 6 are integrally provided on both side surfaces of the partition wall portion 4G. As a result, as shown in FIG. 3, the left end portion 5L side (one end portion side) of the first cover member 5 and the right end portion 6R side (one end portion side) of the second cover member 6 are attached to the case main body in a state of overlapping with the partition wall portion 4G interposed therebetween. Therefore, compared with a configuration in which the first cover member 5 and the second cover member 6 are arranged side by side and fixed on the same surface of the case main body 4, the case main body 4 can be downsized.

[0052] Also, since the first boss portion 43 and the second boss portion 50 are integrally provided on both side surfaces of the partition wall portion 4G, the rigidity of the partition wall portion 4G can be increased. Therefore, the rigidity of the crank-shaped portion of the case main body 4 can be effectively increased, and the strength of the case main body 4 can be further improved.

[0053] Further, according to the present embodiment, since the partition wall portion 4G has an insertion hole 49 through which the coil 2 is inserted, the end portion 2A of the coil 2 can be arranged inside the device case 3 and connected to the wiring board 9. Therefore, since no insertion hole communicating with the outside is formed in the device case 3, the waterproof performance inside the device case 3 can be enhanced.

[0054] Also, in the present embodiment, the coil 2 is housed in a coil housing groove 76 formed in the coil fixing surface 7B (surface) of the coil case 7 and is arranged in a spiral shape on the surface of the coil case 7. Therefore, since the coil 2 is held by the coil case 7 and the swinging during use can be suppressed, the coil can be protected from the vibration during the running of the electric vehicle 200. Further, since the coil 2 is arranged on the surface of the coil case 7, the coil case can be made thinner, and thus the coil unit 1 can be made thinner and lighter.

[0055] Also, in the present embodiment, the case body 4 has a recess 44 formed in the surface facing the first cover member 5 in the wall portions (front wall portion 4A, rear wall portion 4B, right wall portion 4D, partition wall portion 4G) forming the first accommodation space S1, and the recess 44 is filled with a sealing material X. The first cover member 5 has a convex portion 54 formed in the surface facing the wall portions 4A, 4B, 4D, 4G of the first accommodation space S1, and the convex portion 54 is inserted into the recess 44 and attached to the case body 4 with the sealing material X interposed between the wall portions 4A, 4B, 4D, 4G. When the difference in linear expansion and contraction between the case body 4 and the first cover member 5 increases due to the installation environment of the coil unit 1 or the like, the sealing material X interposed between the recess 44 and the convex portion 54 deforms. Therefore, the difference in linear expansion and contraction can be efficiently absorbed on the surfaces in a plurality of directions, and the opening of the first accommodation space S1 can be prevented.

[0056] In addition, in the present embodiment, inclined surfaces 45 with chamfered corners on the side of the first accommodation space S1 are formed on the wall portions 4A, 4B, 4D, 4G of the case body 4, and the sealing material X pushed out to the first accommodation space S1 side is retained by the inclined surfaces 45. Therefore, a thick sealing layer is formed on the inclined surface 45, and the airtightness of the first accommodation space S1 is enhanced, so that the waterproof performance of the device case 3 can be improved. Further, since the surplus sealing material X is retained on the inclined surface 45 to prevent it from flowing into the first accommodation space, components such as the coil 2 accommodated in the first accommodation space S1 can be protected from the sealing material X.

[0057] Note that it is also possible to form a thick portion of the sealing material X between the case body 4 and the first cover member 5 by forming a stepped portion at the corner on the side of the first accommodation space S1 of the wall portions 4A, 4B, 4D, 4G. However, by forming the corner in an inclined surface shape, the extrusion of the sealing material X can be made smooth.

[0058] Furthermore, in the present embodiment, in a state where the first cover member 5 is attached to the case body 4, as shown in FIG. 20, the separation distance t2 between the tip of the convex portion 54 of the first cover member 5 and the bottom surface 442 of the concave portion 44 of the case body 4 is set to be larger than the separation distance t1 between the side surface of the convex portion 54 and the side surface 441 of the concave portion 44. That is, the thickness of the sealing layer (sealing material) formed between the tip of the convex portion 54 and the bottom surface 442 of the concave portion is set to be larger than the thickness of the sealing layers formed on both sides of the convex portion 54. Since the space on the bottom surface 442 side of the concave portion 44 communicates with the spaces on both sides of the convex portion 54, by thickening the sealing layer in the space on the bottom surface 442 side, the deformation of the spaces on both sides of the convex portion 54 due to the difference in linear expansion and contraction between the members can be efficiently absorbed.

[0059] Further, in the present embodiment, the central boss portion 47 (first support portion) formed on the case body 4 is brought into contact with the first cover member 5, and the second support portion 57 formed on the first cover member 5 is brought into contact with the case body 4. Therefore, the case body 4 and the first cover member 5 support each other. Further, in a state where the first cover member 5 is attached to the case body 4, the above-described central boss portion 47 and the second support portion 57 are arranged in a nested manner. Therefore, in a predetermined portion where the strength decreases in the first accommodation space S1, the case body 4 and the first cover member 5 can be efficiently reinforced by supporting each other. As a result, the plate thicknesses of the case body 4 and the first cover member 5 can be reduced.

[0060] Further, in the present embodiment, the central boss portion 47 and the second support portion 57 are arranged in the central space of the coil 2 accommodated in the first accommodation space S1 of the case body 4. Therefore, in the first accommodation space S1 in which the coil 2 is accommodated, the central space of the coil 2 where the strength decreases can be efficiently reinforced.

[0061] Further, in the present embodiment, in a state where the first cover member 5 is attached to the case body 4, the central boss portion 47 of the case body 4 is arranged in a nested manner inside the second support portion 57. That is, since the second support portion 57 of the first cover member 5 has an inner diameter capable of accommodating the central boss portion 47 of the case body 4 inside, the opposing surface of the case body 4 can be supported over a wider range. Therefore, even when the case body 4 is formed of a material that is relatively easy to form, such as aluminum, as in the present embodiment, the strength of the case body 4 can be increased over a wide range, so that both strength and weight reduction can be achieved. Further, even when the case body 4 is die-cast, the structural weakness in die-casting can be compensated for by the structure, so that the required strength can be ensured and the dimensional accuracy and productivity can be improved.

[0062] Also, in the present embodiment, the second support portion 57 has a double cylinder shape having an inner wall 571 and an outer wall 572, and has a plurality of ribs 573 between the inner wall 571 and the outer wall 572. Therefore, the support area of the case body 4 by the second support portion 57 can be increased, and the case body 4 can be more effectively reinforced. Note that it is also possible to increase the support area for the case body 4 by making the second support portion 57 into a single-layer cylinder shape and increasing the plate thickness. However, when applying such a configuration to the resin-made first cover member 5 as in the present embodiment, in addition to an increase in the weight of the first cover member 5, resin sink marks are likely to occur due to an increase in the plate thickness. In the present embodiment, since the second support portion 57 has a structure in which a plurality of ribs are formed inside the double cylinder shape, an increase in the weight of the first cover member 5 can be suppressed, and the occurrence of resin sink marks can be prevented.

[0063] Also, as shown in FIG. 21, in the present embodiment, a screw hole 55 is formed in the central portion of the second support portion 57, and the first cover member 5 is fixed to the case body 4 by inserting a screw 52 through the screw hole 55. Therefore, the central boss portion 47 and the central portion of the second support portion 57 can be fixed and reinforced with the screw 52. Further, in the second support portion 57, an annular convex portion 56 formed so as to surround the screw hole 55 is inserted into the opposing annular concave portion 471 of the case body 4 via a sealing material X, so that waterproof performance around the screw hole 55 can be ensured. Therefore, a coil unit 1 having sufficient strength and excellent waterproof performance can be obtained.

[0064] Also, in the present embodiment, in order to connect the litz wire 21 that constitutes the coil 2 to the wiring board 9, the end portion of the litz wire 21 that is immersed in the solder Y melted in the preliminary soldering process and impregnated with the solder Y is sandwiched by a terminal member 22 fixed to the wiring board 9. Therefore, the solder Y is interposed between the litz wire 21 and the terminal member 22. As a result, for example, compared with a configuration in which the litz wire 21 and the terminal member 22 are brought into direct contact and crimped by caulking, the contact portion between the litz wire 21 and the terminal member 22 is stabilized, and the contact resistance can be reduced. Further, by attaching the solder Y so as to cover the sandwiching portion 24 of the litz wire 21 and the terminal member 22, the mechanical fixing strength between the litz wire 21 and the terminal member 22 can be easily ensured without increasing the contact resistance. Further, since the litz wire 21 is sandwiched by the terminal member 22, stress on the solder due to vibrations and impacts of the vehicle can be reduced.

[0065] Also, in the present embodiment, since the sandwiching portion 24 of the terminal member 22 sandwiches the litz wire 21 with a pair of elastically deformable arms 241, the sandwiching portion 24 can sandwich a plurality of types of litz wires 21 having different diameters. Therefore, since a plurality of types of litz wires 21 having different diameters can be connected to the wiring board 9 by a common terminal member 22, the members can be made common, and a connection structure with excellent versatility can be provided.

[0066] Hereinafter, each modification applicable to the above embodiment will be described. For the same components as those in the above-described embodiment, the same reference numerals are given and the description thereof is omitted.

[0067] In the above-described embodiment, recesses 44 are formed in the wall portions 4A, 4B, 4D, 4G of the case body 4 on the opposing surfaces of the wall portions 4A, 4B, 4D, 4G forming the side wall portion of the first accommodation space S1 and the first cover member 5, and convex portions 54 are formed on the first cover member 5. However, the present invention is not limited to this. For example, as in the modification shown in FIG. 22(A), convex portions 500 may be formed on the wall portions 4A, 4B, 4D, 4G of the case body 4 and inserted into recesses 503 formed on the opposing surfaces of the first cover member 5. Further, in the above-described embodiment, the shape of the recess 44 formed in the case body 4 is a rectangular groove shape, but the present invention is not limited to this. For example, as shown in FIG. 22(B), a convex portion 602 having a hemispherical cross section may be inserted into a groove-shaped recess 600 having a hemispherical cross section. Alternatively, as in the modification shown in FIG. 22(C), a trapezoidal convex portion 702 may be inserted into a groove-shaped recess 700 having a trapezoidal cross section. Also, a triangular convex portion may be inserted into a groove-shaped recess having a triangular cross section.

[0068] Also, in the above-described embodiment, the central boss portion 47 (first support portion) and the second support portion 57 are configured such that the central boss portion 47 protruding from the case body 4 side enters the inside of the second support portion 57 and is arranged in a nested manner. However, the present invention is not limited to this. As shown in the modified example of FIG. 23, the second support portion 900 protruding from the first cover member 5 may be inserted into the inside of the central boss portion 800 (first support portion) and arranged in a nested manner. The central boss portion 800 (first support portion) according to the modified example shown in this figure is formed in a cylindrical shape protruding from the upper wall portion 4E of the case body 4 toward the first cover member 5 side. In the center of the central boss portion 800, a cylindrical protrusion protruding downward is formed, and a female screw hole is formed in the center of the protrusion. In the central boss portion 800, an annular recess 802 in the shape of a rectangular groove is formed on the surface facing the first cover member 5, and an annular convex portion 902 protruding from the first cover member 5 is inserted inside the recess 802 with a sealing material X interposed therebetween. On the other hand, the second support portion 900 according to the modified example is arranged inside an annular convex portion 902 formed so as to surround a screw hole 55 formed in the central portion of the first cover member 5, and is formed in a cylindrical shape protruding from the first cover member 5 toward the case body 4 side. The second support portion 900 has a double-cylindrical shape formed by an inner wall 904 formed so as to surround the periphery of the screw hole 55 and an outer wall 906 coaxially arranged on the radially outer side of the inner wall 904, and has a plurality of ribs 908 between the inner wall 904 and the outer wall 906. In a state where the first cover member 5 is attached to the case body 4, the second support portion 900 is arranged in a nested manner inside the first support portion 800, and the second support portion 57 abuts against the case body 4 to support the case body 4.

[0069] In addition, in the above-described embodiment and each modified example, the coil unit of the non-contact charging system using the magnetic resonance method has been described. However, the coil unit of the present invention is not limited to this, and it may be applied to a non-contact charging system using the electromagnetic induction method.

Explanation of Reference Numerals

[0070] 1 Coil unit (1A, 1B) 2 Coil 4 Case body 4A Front wall part (wall part) 4B Rear wall part (wall part) 4D Right wall part (wall part) 4G Partition wall part (wall part) 5 First cover member (cover member) 9 Wiring board 44 Recess 45 Inclined surface 54 Protrusion 100 Non-contact power feeding system 200 Electric vehicle 300 Battery S1 First accommodation space (accommodation space) X Sealing material t1 Separation distance t2 Separation distance

Claims

1. A coil unit disposed on the ground or in an electric vehicle in a non-contact charging system that transmits power between a power transmission side coil unit disposed on the ground and a power reception side coil unit disposed in the electric vehicle and charges a battery mounted on the electric vehicle, a coil formed in a spiral shape, a wiring board to which the coil is connected, a case body having a housing space for housing the coil, and a cover member attached to the case body to close the housing space. The case body has a wall portion forming the housing space and a recess formed on a surface of the wall portion facing the cover member. The cover member has a convex portion formed on a surface of the cover member facing the wall portion. The cover member is attached to the case body with the convex portion inserted into the recess filled with a sealing material and the sealing material interposed between the cover member and the wall portion. The sealing material is provided between a side surface of the convex portion and a side surface of the recess. The coil unit.

2. The coil unit according to claim 1, wherein the wall portion has an inclined surface with rounded corners on the housing space side.

3. The coil unit according to claim 1 or 2, wherein in a state where the cover member is attached to the case body, a separation distance between a tip of the convex portion and a bottom surface of the recess is set to be larger than a separation distance between a side surface of the convex portion and a side surface of the recess.

4. A coil unit disposed on the ground or in an electric vehicle in a non-contact charging system that transmits power between a power transmission side coil unit disposed on the ground and a power reception side coil unit disposed in the electric vehicle and charges a battery mounted on the electric vehicle, a coil formed in a spiral shape, a wiring board to which the coil is connected, A case body having an accommodation space for accommodating the coil, and a cover member attached to the case body to close the accommodation space. The case body has a wall portion forming the accommodation space and a recess formed on a surface of the wall portion facing the cover member. The cover member has a convex portion formed on a surface of the cover member facing the wall portion. The cover member is attached to the case body with the convex portion inserted into the recess filled with a sealing material and the sealing material interposed between the cover member and the wall portion. The wall portion has an inclined surface with chamfered corners on the accommodation space side, which is a coil unit.

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