Coil unit and installation structure of coil unit

Abstract

To provide a coil unit and an installation structure of the coil unit capable of improving maintainability and robustness.SOLUTION: The coil unit 10 includes a coil structure 11, a lid portion 12, an accommodation portion 17, and an electric device 19. The coil structure 11 includes a coil 21 and a coil support unit 22 that supports the coil 21. The accommodation portion 17 is disposed in a through-hole 23 formed in the coil support portion 22. The accommodation portion 17 accommodates the electrical device 19 therein. The lid portion 12 closes and opens an opening end of the through-hole 23 of the coil support portion 22. The lid portion 12 is supported by the housing portion 17 when the through hole 23 is closed.SELECTED DRAWING: Figure 2

Description

[Technical Field]

[0001] The present invention relates to a coil unit and an installation structure for the coil unit. [Background technology]

[0002] In recent years, research and development has been conducted into charging vehicles equipped with secondary batteries that contribute to energy efficiency, in order to ensure that more people have access to affordable, reliable, sustainable and advanced energy. Conventionally, in a contactless power transmission system that supplies power to a vehicle from outside the vehicle by contactless power transmission, a pavement structure is known that includes a case that houses a power transmission coil and is buried in the road, and a cover member that closes the upper opening of the case, with the upper surface of the cover member forming part of the pavement surface (see, for example, Patent Document 1). [Prior art documents] [Patent documents]

[0003] [Patent Document 1] Japanese Patent Publication No. 2023-023997 Summary of the Invention [Problem to be solved by the invention]

[0004] In technologies related to charging and supplying power to vehicles equipped with secondary batteries, it is desirable to improve the ease of maintenance and robustness of coil units when transmitting power contactlessly. For example, if a cover member for a case that entirely houses the power transmission coil is provided, as in the pavement structure of the above-mentioned prior art, the size and weight of the entire structure increase and the desired robustness against loads acting on the cover member may not be ensured. For example, if a coil structure in which a power transmission coil is integrated with a precast road surface manufactured in a factory or the like is embedded in the road, the increased size and weight of the coil structure may increase the effort and cost required for construction. Furthermore, simply providing a columnar support member made of a non-magnetic resin material inserted into the air-core region of the power transmission coil from the bottom wall of the case to support the center of the cover member, as in the pavement structure of the above-mentioned prior art, may not be able to ensure the desired robustness against loads caused by the vehicle weight, load shifts, and the like.

[0005] An object of the present invention is to provide a coil unit and a coil unit installation structure that can improve ease of maintenance and robustness, and that will ultimately contribute to energy efficiency. [Means for solving the problem]

[0006] In order to solve the above problems and achieve the above object, the present invention employs the following aspects. (1): A coil unit according to one aspect of the present invention (e.g., coil unit 10 in the embodiments) includes a coil (e.g., coil 21 in the embodiments) that sends or receives power by contactless power transmission, a coil support portion (e.g., coil support portion 22 in the embodiments) that supports the coil and has a through hole (e.g., through hole 23 in the embodiments) formed along the central axis of the coil (e.g., central axis O in the embodiments), a storage portion (e.g., storage portion 17 in the embodiments) that is placed in the through hole of the coil support portion, an electrical device (e.g., electrical device 19 in the embodiments) that is placed inside the storage portion, and a lid portion (e.g., lid portion 12 in the embodiments) that closes and opens the open end of the through hole of the coil support portion and is supported by the storage portion when closed.

[0007] (2): In the coil unit described in (1) above, the lid portion may protrude further than the coil toward the other side when the power transmission side and the power receiving side of the power transmission face each other in an axial direction parallel to the central axis.

[0008] (3): The coil unit described in (2) above may be provided with a storage lid portion (e.g., storage lid portion 18 in the embodiment) that closes and opens an opening formed in the outer periphery of the storage portion on the lid portion side (e.g., peripheral portion 28 in the embodiment).

[0009] (4): The coil unit described in any one of (1) to (3) above may include a first yoke portion (e.g., first yoke portion 14 in the embodiment) made of a magnetic material that is arranged on the rear side of the coil as viewed from the lid portion side in an axial direction parallel to the central axis, and a second yoke portion (e.g., second yoke portion 15 and third yoke portion 16 in the embodiment) made of a magnetic material that is arranged around the periphery of the accommodating portion within the through hole so as to surround each of the lid portion side and the coil support portion side.

[0010] (5): A coil unit installation structure according to one aspect of the present invention (e.g., installation structures 30, 30a, 30b, 30c, and 30d in the embodiments) comprises a coil unit according to any one of claims 1 to 3 (e.g., coil unit 10 in the embodiments) that is embedded in a running path (e.g., running path R in the embodiments) with the surface of the lid portion exposed to the outside, and a base portion (e.g., base portion 42 in the embodiments) that supports the coil unit inside the running path.

[0011] (6): The coil unit installation structure described in (5) above includes a support portion (e.g., support portions 41, 41a, 41b in the embodiment) installed inside the running path, and the base portion may be fixed to the support portion by adhesive or fastening.

[0012] (7) The coil unit installation structure described in (5) above may include a plate-like member (for example, plate-like member 46 in the embodiment) disposed between the base portion and the inside of the travel path. [Effects of the Invention]

[0013] According to the above (1), the lid that closes the through-hole of the coil support part is supported by the housing that is placed in the through-hole, so that the ease of maintenance, such as repair and replacement, of the electrical equipment housed in the housing is ensured and the robustness of the lid can be improved. For example, compared to a case where a coil structure that integrates a precast road surface and a power transmission coil is buried in the roadway, the ease of construction can be improved and the time required for construction can be reduced while ensuring the desired robustness.

[0014] In the case of (2) above, the lid protrudes further than the coil toward the other side of the power transmission, so that it is possible to prevent an external load acting on the lid from acting directly on the coil.

[0015] In the case of (3) above, the electrical equipment in the storage space can be protected by the storage lid that closes the opening of the storage section, and the lid and storage lid can easily expose the electrical equipment to the outside, improving the ease of maintenance of the electrical equipment.

[0016] In the case of (4) above, the coupling coefficient can be improved by providing the first yoke part and the second yoke part.

[0017] According to (5) above, the load acting on the lid portion from the outside is released directly to the inside of the running path, such as the roadbed, via the storage portion and the base portion, thereby preventing excessive load from acting on the electrical equipment and coils.

[0018] In the case of (6) above, the base portion is fixed to the support portion inside the running track by adhesive or fastening, which improves ease of construction and reduces the time required for construction.

[0019] In the case of (7) above, by providing a plate-like member, it is possible to stably support the coil unit against the inside of the roadway, such as the roadbed. [Brief explanation of the drawings]

[0020] [Figure 1] FIG. 2 is a perspective view of a coil unit according to an embodiment of the present invention. [Figure 2] 2 is a cross-sectional view of the coil unit according to the embodiment of the present invention, taken along line ABC in FIG. 1 and parallel to the YZ plane and the ZX plane. [Figure 3] 2 is a cross-sectional view of an example of a coil unit and an installation structure according to an embodiment of the present invention, taken along a ZX plane (a plane perpendicular to the Y axis) at the position of line DD shown in FIG. 1. [Figure 4] 2 is a cross-sectional view of another example of the coil unit and installation structure according to the embodiment of the present invention, taken along the ZX plane (a plane perpendicular to the Y axis) at the position of the line DD shown in FIG. 1. [Figure 5]FIG. 2 is a plan view of the coil unit according to the embodiment of the present invention, viewed from the Z-axis direction with the lid portion omitted. [Figure 6] 2 is a cross-sectional view of the coil unit according to the embodiment of the present invention and the installation structure of the first modified example, taken along the ZX plane (a plane perpendicular to the Y axis) at the position of the line DD shown in FIG. 1. [Figure 7] 2 is a cross-sectional view of the coil unit according to the embodiment of the present invention and the installation structure of the second modified example, taken along the ZX plane (a plane perpendicular to the Y axis) at the position of the line DD shown in FIG. 1. FIG. DETAILED DESCRIPTION OF THE INVENTION

[0021] Hereinafter, a coil unit and a coil unit installation structure according to an embodiment of the present invention will be described with reference to the accompanying drawings. The coil unit 10 of the embodiment constitutes, for example, at least one of a power transmitting device and a power receiving device of a contactless power transmission system that supplies power from the outside of a mobile body such as a vehicle to the mobile body by contactless power transmission. The coil unit 10 of the embodiment is provided in, for example, a power transmitting device installed on a running path of the mobile body.

[0022] Fig. 1 is a perspective view of a coil unit 10 according to an embodiment. Fig. 2 is a cross-sectional view of the coil unit 10 according to an embodiment, taken along a plane parallel to each of the YZ plane and the ZX plane at the position of line ABC shown in Fig. 1. Fig. 3 is a cross-sectional view of an example (30a) of the coil unit 10 according to an embodiment and an installation structure 30 taken along a ZX plane (a plane perpendicular to the Y axis) at the position of line DD shown in Fig. 1. Fig. 4 is a cross-sectional view of another example (30b) of the coil unit 10 according to an embodiment and an installation structure 30 taken along a ZX plane (a plane perpendicular to the Y axis) at the position of line DD shown in Fig. 1.

[0023] In the following description, the X-axis, Y-axis, and Z-axis directions, which are orthogonal to each other in three-dimensional space, are parallel to each other. For example, as shown in Fig. 1, the X-axis and Y-axis directions are parallel to the front-rear and left-right directions of the coil unit 10, and the Z-axis direction is parallel to the up-down direction (thickness direction) of the coil unit 10. For example, the positive Z-axis direction is the direction toward the other side when the power transmitting coil and the power receiving coil of a contactless power transfer system face each other.

[0024] As shown in Figures 1 to 4, the coil unit 10 of the embodiment includes, for example, a coil structure 11, a lid portion 12, a coil base portion 13, a plurality of first yoke portions 14, second yoke portions 15 and third yoke portions 16, an accommodating portion 17, an accommodating lid portion 18, and an electrical device 19.

[0025] The coil structure 11 includes, for example, a coil 21 and a coil support portion 22 that supports the coil 21. The coil 21 has an outer shape in which an electric wire such as a rectangular copper wire is wound around a central axis O in a spiral shape with rounded corners.

[0026] The coil support part 22 has an outer shape that is, for example, a rounded rectangular annular plate that covers the entire coil 21 and has a through hole 23 formed coaxially along the central axis O of the coil 21. The coil support part 22 is formed by casting a thermally conductive resin such as polycarbonate or urethane. The coil support portion 22 includes, for example, a wall portion 22a that protrudes upward from the upper surface 22A on the inner periphery between an inner periphery wall 23A that forms the through hole 23 and the inner periphery of the coil 21. The outer shape of the wall portion 22a is, for example, a rounded rectangular cylindrical shape. The wall portion 22a and an inner periphery portion 22b that is more inward than the wall portion 22a form a space in which the outer periphery of the lid portion 12 (described later) is disposed, for example, at a position above the coil 21 in the axial direction parallel to the central axis O. Note that the tip (upper end) of the wall portion 22a is set so as not to protrude upward at least above the upper end of the lid portion 12.

[0027] The outer shape of the lid portion 12 is, for example, a rectangular plate with rounded corners. The lid portion 12 is formed of, for example, a resin material such as fiber reinforced plastics (FRP) and a metal material such as aluminum. The lid portion 12 closes and opens the upper open end of the through hole 23 of the coil support portion 22. The lid 12 has, for example, legs 12a that protrude downward from a lower surface 12A at an outer periphery that is offset inward from the outer periphery. The outer shape of the legs 12a is, for example, a rounded rectangular tubular shape. The legs 12a are supported by coming into contact with the housing 17 (described later) when the through-hole 23 is closed. The lid 12 is fastened to the housing 17 by, for example, a plurality of bolts 24 that are inserted into a plurality of bolt holes that pass through the portion where the legs 12a are provided in the thickness direction.

[0028] The outer shape of the coil base 13 is, for example, a rounded rectangular annular plate with a through hole 25 formed coaxially therewith, which is in communication with the through hole 23 of the coil support part 22. For example, the size of the outer periphery of the coil base 13 and the through hole 25 is the same as the size of the outer periphery of the coil support part 22 and the through hole 23. The coil base 13 is formed, for example, from a thermally conductive resin such as polycarbonate. The coil base 13 is in integral contact with the lower part of the coil support part 22 and supports the coil support part 22. The coil base 13 holds, for example, a plurality of first yoke parts 14 (described later) that are arranged between the coil base 13 and the coil support part 22. The inner peripheral walls 25A, 23A that form the respective through holes 25, 23 of the coil base 13 and the coil support part 22 hold a plurality of second yoke parts 15 (described later) that are fixed by, for example, adhesive or the like. The coil base 13 includes, for example, a plurality of base portions 13a that protrude inward from an inner peripheral wall 25A that forms the through hole 25. The coil base 13 is fastened to a base portion 42 (described later) by, for example, bolts that are inserted into bolt holes that pass through each base portion 13a in the thickness direction.

[0029] The outer shape of each of the plurality of first yoke parts 14, the plurality of second yoke parts 15, and the plurality of third yoke parts 16 is, for example, a rectangular plate. Each of the yoke parts 14, 15, and 16 is formed from a magnetic material such as ferrite, a nanocrystalline soft magnetic sheet, or an electromagnetic steel sheet. The multiple first yoke portions 14 are arranged, for example, between the coil base 13 and the coil support portion 22 with the central axis of each first yoke portion 14 parallel to the central axis O. The multiple first yoke portions 14 are arranged on the rear side of the coil 21 when viewed from the lid portion 12 side, in an axial direction parallel to the central axis O. The multiple second yoke portions 15 are arranged, for example, on inner peripheral walls 25A, 23A that form the respective through holes 25, 23 of the coil base 13 and the coil support portion 22, with the central axis of each second yoke portion 15 parallel to a direction perpendicular to the central axis line O. The plurality of third yoke portions 16 are arranged on the upper surface of the housing lid portion 18, which will be described later, with the central axis of each third yoke portion 16 parallel to the central axis line O, for example. For example, a plurality of first yoke portions 14 provided as a back yoke of the coil 21, and a plurality of second yoke portions 15 and a plurality of third yoke portions 16 surrounding the accommodating portion 17 described later in the air-core region of the coil 21 form a box-shaped magnetic circuit with a flange.

[0030] The outer shape of the accommodation section 17 is, for example, a box shape with an opening at the top. The accommodation section 17 is made of, for example, an aluminum alloy or the like. In the accommodation space 17a formed inside the accommodation section 17, there are arranged electrical equipment 19 such as a power converter such as an inverter formed by a plurality of switching elements and rectifying elements, resistors and capacitors (condensers) connected to the coil 21 to form a resonant circuit, and various boards.

[0031] The accommodation portion 17 includes, for example, a first flange portion 26 and a plurality of second flange portions 27 that protrude outward from the outer peripheral surface. The first flange portion 26 is, for example, provided continuously around the entire circumference of the outer peripheral surface of the accommodation portion 17. The plurality of second flange portions 27 are, for example, provided so as to protrude radially from a plurality of predetermined positions on the outer peripheral surface of the accommodation portion 17. The plurality of predetermined positions on the outer peripheral surface of the accommodation portion 17 are, for example, four corners and a center portion between two adjacent corners. The accommodating portion 17 is fastened to the base portion 42 described later, for example, by a plurality of bolts that are inserted into a plurality of bolt holes that penetrate the first flange portion 26 in the thickness direction (direction parallel to the central axis O). Each of the multiple second flange portions 27 supports a leg portion 12a of the lid portion 12 that closes the through hole 23 of the coil support portion 22. The accommodating portion 17 fastens and fixes the lid portion 12 with each bolt 24 that is attached to each bolt hole of the lid portion 12 and to bolt holes provided in the thickness direction of each second flange portion 27.

[0032] The housing lid 18 is formed of, for example, an aluminum alloy such as aluminum with magnesium added. The housing lid 18 closes and opens an opening formed in the upper part of the housing part 17. The housing lid 18 is fastened to an upper peripheral edge 28 surrounding the open end of the housing part 17, for example, by a plurality of bolts that are attached to a plurality of bolt holes that pass through the housing lid 18 in the thickness direction.

[0033] 3 and 4, the coil unit 10 of the embodiment is embedded in the running path R with the upper surface 12B of the lid portion 12 exposed to the outside as an installation structure 30. For example, the upper surface 12B of the lid portion 12 and the road surface of the running path R form the same plane.

[0034] 3 corresponds to the case where the road R is a high-standard road such as an expressway or a motorway. The installation structure 30a includes, for example, a support portion 41a (41), a base portion 42, and a backfilling filling portion 43a (43). The support portion 41a (41) is, for example, a plate-like member that is placed on the roadbed inside the excavated travel path R. The support portion 41a is made of, for example, unreinforced concrete. The base portion 42 is, for example, a plate-like member disposed between the support portion 41a and the coil unit 10. The base portion 42 is formed, for example, from resin mortar or the like. The base portion 42 is adhered and fixed to the support portion 41a by, for example, a resin adhesive.

[0035] The backfilling filling portion 43a (43) is formed, for example, by excavating the travel path R and backfilling and filling the internal space in which the coil unit 10 is disposed. For example, the upper surface 43A of the backfilling filling portion 43a and the upper surface 12B of the lid portion 12 form the same plane. The backfilling filling portion 43a includes, for example, an outer layer portion 44a exposed to the outside and an inner layer portion 44b. The outer layer portion 44a is provided, for example, toward the internal space and up to the upper surface 22A of the coil support portion 22. The outer layer portion 44a is formed, for example, from densely graded asphalt or the like. The inner layer portion 44b is provided, for example, between the outer layer portion 44a and the support portion 41a. The inner layer portion 44b is formed, for example, from resin mortar or the like.

[0036] 4 corresponds to the case where the road R is a road other than a high-standard road such as a general road. The installation structure 30b includes, for example, a support portion 41b (41), a base portion 42, and a backfilling filling portion 43b (43). The support portion 41b (41) is, for example, a predetermined layer that is installed on the roadbed inside the excavated travel path R. The support portion 41b is formed of, for example, grain-adjusted crushed stone or the like. The base portion 42 is, for example, a plate-like member disposed between the support portion 41b and the coil unit 10. The base portion 42 is formed of, for example, resin mortar or the like.

[0037] The backfilling filling portion 43b (43) is formed, for example, by excavating the travel path R and backfilling and filling the internal space in which the coil unit 10 is disposed. For example, the upper surface 43A of the backfilling filling portion 43b and the upper surface 12B of the lid portion 12 form the same plane. The backfilling filling portion 43b includes, for example, an outer layer portion 44c exposed to the outside. The outer layer portion 44c is provided, for example, from the inner space to the support portion 41b. The outer layer portion 44c is made of, for example, resin mortar.

[0038] As described above, according to the coil unit 10 of the embodiment, the lid 12 that closes the through hole 23 of the coil support portion 22 is supported by the housing portion 17 that is disposed in the through hole 23, which ensures ease of maintenance, such as repair and replacement, of the electrical equipment 19 housed in the housing portion 17, and also improves the robustness of the lid 12. Compared to, for example, a case in which a coil structure that integrates a precast road surface and a power transmission coil is buried in a roadway, the ease of construction is improved and the time required for construction can be reduced while ensuring the desired robustness.

[0039] Since lid portion 12 protrudes further than coil 21 toward the other side of power transmission (power receiving side), it is possible to prevent a load acting on lid portion 12 from the outside from acting directly on coil 21. The electrical equipment 19 in the storage space 17a can be protected by the storage lid portion 18 that closes the opening of the storage portion 17, and the lid portion 12 and the storage lid portion 18 can easily expose the electrical equipment 19 to the outside, improving the ease of maintenance of the electrical equipment 19. The coupling coefficient can be improved by providing the first yoke part 14, the second yoke part 15, and the third yoke part 16 that form a magnetic circuit.

[0040] According to the installation structure 30 of the embodiment, the load acting on the lid portion 12 from the outside is released directly to the inside of the running road R, such as the roadbed, via the storage portion 17 and the base portion 42, thereby preventing excessive load from acting on the electrical equipment 19 and the coil 21.

[0041] (Variation) Modifications of the embodiment will be described below. Note that the same parts as those in the above-described embodiment will be denoted by the same reference numerals, and descriptions thereof will be omitted or simplified. In the installation structure 30a of the above-described embodiment, the base portion 42 is adhered and fixed to the support portion 41a by, for example, a resin adhesive, but the present invention is not limited to this. FIG. 6 is a cross-sectional view of the coil unit 10 of the embodiment and the installation structure 30c (30) of the first modified example, taken along the ZX plane (plane perpendicular to the Y axis) at the position of the line DD shown in FIG. As shown in FIG. 6, the installation structure 30c of the first modified example may include a bolt 45 that fastens the base portion 42 to the support portion 41a. According to the first modified example, the base portion 42 is fixed to the support portion 41a inside the running track R by adhesion or fastening, which improves ease of construction and reduces the time required for construction.

[0042] In the installation structure 30b of the above-described embodiment, the base portion 42 is disposed between the support portion 41b and the coil unit 10, but the present invention is not limited to this. FIG. 7 is a cross-sectional view of the coil unit 10 of the embodiment and the installation structure 30d (30) of the second modified example, taken along the ZX plane (plane perpendicular to the Y axis) at the position of the line DD shown in FIG. 7, the installation structure 30d of the second modification may include a plate-like member 46 disposed between the base portion 42 and the support portion 41b. The plate-like member 46 may be made of a metal material such as aluminum. According to the second modification, by providing the plate-like member 46, it is possible to stably support the coil unit 10 against the inside of the travel road R, such as the roadbed.

[0043] In the above-described embodiment, the wall portion 22a and the inner peripheral portion 22b of the coil support portion 22 form a space in which the outer peripheral portion of the lid portion 12 is arranged, but this is not limited to this, and at least one of the wall portion 22a and the inner peripheral portion 22b may contact the outer peripheral portion of the lid portion 12 and support the lid portion 12.

[0044] In the above-described embodiment, the tip (upper end) of the wall portion 22a of the coil support portion 22 may form the same surface as the road surface of the running path R together with the upper surface 12B of the lid portion 12, or may be covered by the backfill filling portion 43.

[0045] The embodiments of the present invention are presented as examples and are not intended to limit the scope of the invention. These embodiments can be embodied in various other forms, and various omissions, substitutions, and modifications can be made without departing from the spirit of the invention. These embodiments and their modifications are intended to be included within the scope and spirit of the invention, as well as within the scope of the invention and its equivalents as defined in the claims. [Explanation of symbols]

[0046] 10...coil unit, 11...coil structure, 12...lid portion, 13...coil base portion, 14...first yoke portion, 15...second yoke portion, 16...third yoke portion, 17...accommodation portion, 18...accommodation lid portion, 19...electrical equipment, 21...coil, 22...coil support portion, 23...through hole, 23A...inner peripheral wall, 24...bolt, 25...through hole, 25A...inner peripheral wall, 26...first flange portion, 27...second flange portion, 30, 30a, 30b, 30c, 30d...installation structure, 41, 41a, 41b, support portion, 42...base portion, 43, 43a, 43b...backfilling filling portion, 44a...outer layer portion, 44b...inner layer portion, 44c...outer layer portion, 45...bolt, 46...plate-shaped member, R...running path.

Claims

1. a coil that sends or receives power by contactless power transmission; a coil support portion that supports the coil and has a through hole formed along a central axis of the coil; a housing portion disposed in the through hole of the coil support portion; an electrical device disposed inside the housing; a lid portion that closes and opens the open end of the through hole of the coil support portion and is supported by the accommodation portion when closed; Equipped with Coil unit.

2. The cover portion protrudes beyond the coil toward the other side in an axial direction parallel to the central axis when the power transmission side and the power receiving side of the power transmission face each other. The coil unit according to claim 1 .

3. and a storage lid portion that closes and opens an opening formed in a portion of the outer periphery of the storage portion on the lid portion side. The coil unit according to claim 2 .

4. a first yoke portion made of a magnetic material and arranged on the rear side of the coil as viewed from the lid portion side in an axial direction parallel to the central axis; a second yoke portion made of a magnetic material that is arranged to surround the lid portion side and the coil support portion side of the periphery of the accommodation portion within the through hole; Equipped with The coil unit according to any one of claims 1 to 3.

5. The coil unit according to any one of claims 1 to 3, which is embedded in a running path with a surface of the lid portion exposed to the outside; a base portion that supports the coil unit inside the travel path; Equipped with Coil unit installation structure.

6. a support portion installed inside the travel path; The base portion is fixed to the support portion by adhesive or fastening. The coil unit installation structure according to claim 5.

7. a plate-shaped member disposed between the base portion and the inside of the running path; The coil unit installation structure according to claim 5.

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