Coil components, coils, power transmission equipment, power receiving equipment, and power transmission systems

Abstract

To provide a coil component which can secure good strength and good coil characteristics.SOLUTION: A coil component 10A according to one embodiment includes: a coil 11 including a spiral shaped conductor 11E including multiple turn parts 12n arranged at the radial outer side from a center axis C of the spiral shape; a case 20 serving as a storage member for storing the coil 11; and one or multiple pillars 30 which extend in an axial direction of the coil 11 and pass through the coil 11. At least one of both ends of the pillar 30 is connected to an inner surface of the case 20.SELECTED DRAWING: Figure 3

Description

Technical Field

[0001] The present disclosure relates to coil components, coils, power transmission devices, power reception devices, and power transmission systems.

Background Art

[0002] Wireless power transmission systems that transmit power without contact are becoming increasingly popular.

[0003] When transmitting a large amount of power without contact, a large high-frequency current flows through a resonance circuit including a coil. At this time, the amount of heat generated by the coil increases. The amount of heat generated by the coil increases, for example, due to the skin effect.

[0004] When using Litz wire as the coil, the skin effect is suppressed. Therefore, heat generation of the coil can be suppressed. However, since Litz wire is formed by twisting a large number of enameled wires, the manufacturing cost is high and the manufacturing is laborious. In a high-power system, since the coil can be large, the manufacturing cost and the laboriousness of manufacturing can further increase.

[0005] On the other hand, a technique of adopting a planar coil that is spiral and plate-shaped and has a rectangular cross-section of the conductor is also known (see Patent Document 1). According to such a planar coil, the manufacturing efficiency can be improved regardless of the size of the coil. Therefore, such a planar coil is suitable for a high-power system in which the size of the coil can be large.

[0006] In a wireless power transmission system for an electric vehicle, a power transmission device is installed on a road surface such as a parking lot, and a power reception device is installed on the electric vehicle. For example, when using the above planar coil for an electric vehicle, the height dimension can be particularly suppressed in both the power transmission device and the power reception device. Therefore, the above planar coil functions beneficially in a vehicle field where space constraints are severely imposed.

Prior Art Documents

Patent Documents

[0007] [Patent Document 1] Japanese Patent Publication No. 2021-27112 [Overview of the project] [Problems that the invention aims to solve]

[0008] For example, in power transmission equipment installed on road surfaces, the coil is usually housed in a case. The case typically has a bottom wall, side walls that rise from the bottom wall and surround the outer circumference of the coil, and a top wall that closes the side walls.

[0009] When a planar coil, as disclosed in Patent Document 1, is housed in a power transmission device case, the planar coil may be held apart from both the top and bottom walls. However, in this configuration, for example, when a load from a vehicle is transmitted from the top wall to the side wall of the case, only the side wall bears the load. Furthermore, the top wall may bend and come into contact with the planar coil, potentially causing the planar coil to bend or the spacer to break. As a result, the strength of the power transmission device may become insufficient.

[0010] One might consider making the case heavier to improve its strength, but in this case, there is a risk that the desired coil characteristics may not be obtained due to constraints on the coil size.

[0011] This disclosure has been made in consideration of the above circumstances, and its objective is to provide coil components, coils, power transmission equipment, power receiving equipment, and power transmission systems that can ensure good strength and good coil characteristics. [Means for solving the problem]

[0012] A coil component according to one embodiment comprises a coil including a conductor having a spiral shape, the conductor including a plurality of turns arranged radially outward from the central axis of the spiral shape, a housing member for housing the coil, and one or more support columns extending in the axial direction of the coil and passing through the coil, wherein at least one of the ends of the support columns is connected to the inner surface of the housing member, in contact with the inner surface of the housing member, or away from the inner surface of the housing member and facing the inner surface.

[0013] The one or more of the aforementioned support columns may include a first support column located radially inward of the turn portion located at the innermost circumference.

[0014] The one or more of the aforementioned support columns may include a second support column that passes between the radially adjacent turn portions.

[0015] The second support column may be located between the second turn portion from the radially inward side of the coil and the second turn portion from the radially outward side of the coil.

[0016] The gap between the radially adjacent turn portions through which the second support column passes may include a first region through which the second support column passes and a second region whose radial width is narrower than the radial width of the first region.

[0017] Each of the radially adjacent turn portions that form a gap through which the second support column passes, the inner turn portion located radially inward and the outer turn portion located radially outward, may have a first straight portion and a second straight portion extending along a straight line, and a corner portion connecting the first straight portion and the second straight portion. The corner portion may be arc-shaped, straight, or broken along an arc, the first straight portion may extend linearly from one end of the corner portion, and the second straight portion may extend linearly from the other end of the corner portion. In the inner turn portion and the outer turn portion, each first straight portion is radially adjacent, each second straight portion is radially adjacent, the distance between the ends of the corner portion of the outer turn portion is smaller than the distance between the ends of the corner portion of the inner turn portion, and the first region may be the region between the corner portion of the inner turn portion and the corner portion of the outer turn portion.

[0018] The corner portion of the inner turn and the corner portion of the outer turn are arc-shaped, and the curvature of the corner portion of the inner turn may be smaller than the curvature of the corner portion of the outer turn.

[0019] When viewed in the axial direction of the coil, the storage member is rectangular in shape, and when viewed in the axial direction of the coil, the second support column may be located on the diagonal of the storage member, or within the range enclosed by line segments extending to positions obtained by rotating the diagonal of the storage member by ±10 degrees around the center of the storage member.

[0020] The inner turn portion located radially inward and the outer turn portion located radially outward, among the radially adjacent turn portions that form the gap through which the second support column passes, may each have a straight portion extending along a straight line. The second support column may pass between the straight portions of the adjacent inner turn portions and the straight portions of the outer turn portions.

[0021] Also, the coil component according to one embodiment further includes an insulating member that contacts the coil in the axial direction of the coil. A through-hole that overlaps a gap between the turn portions adjacent to each other in the radial direction through which the second support column passes is formed in the insulating member, and the second support column may pass through the through-hole and the gap.

[0022] Each of the inner turn portion located inward in the radial direction and the outer turn portion located outward in the radial direction among the turn portions adjacent to each other in the radial direction that form the gap through which the second support column passes has a straight portion extending along a straight line, and the through-hole may overlap the gap between the straight portions of the inner turn portion and the straight portions of the outer turn portion adjacent to each other.

[0023] The coil may be separated from the inner surface of the storage member to which the support column is connected, contacts, or faces.

[0024] The storage member has a side wall portion surrounding the outer circumference of the coil and a top wall portion closing the side wall portion, and the support column may be integrally connected to the top wall portion.

[0025] The support column is separate from the storage member and may be sandwiched between opposing portions on the inner surface of the storage member or between the inner surface of the storage member and another member.

[0026] The support column may be non-magnetic and insulating.

[0027] A coil according to one embodiment comprises a conductor having a spiral shape, the conductor includes a plurality of turn portions arranged radially outward from the central axis of the spiral shape, and each of the inward turn portion and the outward turn portion located radially outward in at least one pair of radially adjacent turn portions in the plurality of turn portions has a first straight portion and a second straight portion extending along a straight line, and a corner portion connecting the first straight portion and the second straight portion, the corner portion being arc-shaped, straight, or bent along an arc, and the first straight portion being the corner portion The coil comprises a coil having a linear extension from one end, a second linear extension from the other end of the corner portion, and in the inner turn portion and the outer turn portion, each of the first linear portions is adjacent in the radial direction, each of the second linear portions is adjacent in the radial direction, the distance between the ends of the corner portion of the outer turn portion is smaller than the distance between the ends of the corner portion of the inner turn portion, and the gap between the inner turn portion and the outer turn portion includes a first region between the corner portion of the inner turn portion and the corner portion of the outer turn portion, and a second region whose radial width is narrower than the radial width of the first region.

[0028] Furthermore, the power transmission device according to one embodiment includes the aforementioned coil component. Furthermore, the power receiving device according to one embodiment includes the aforementioned coil component. Furthermore, a power transmission system according to one embodiment comprises a power transmission device and a power receiving device, wherein at least one of the power transmission device and the power receiving device comprises the coil component. [Effects of the Invention]

[0029] According to this disclosure, good strength and good coil characteristics can be ensured in the coil component. [Brief explanation of the drawing]

[0030] [Figure 1]This diagram schematically shows a wireless power transmission system to which the coil component according to the embodiment may be applied. [Figure 2] This is a perspective view of a coil component according to the first embodiment. [Figure 3] This is a cross-sectional view of the coil component along the line III-III in Figure 2. [Figure 4] This is a perspective view of the coil and insulating member constituting the coil component according to the first embodiment. [Figure 5] This is a plan view of the coil and insulating member constituting the coil component according to the first embodiment. [Figure 6] This is a perspective view of a coil component according to the second embodiment. [Figure 7] This is a perspective view of the coil and insulating member constituting the coil component according to the second embodiment. [Figure 8] This figure illustrates a method for manufacturing a coil component according to a second embodiment. [Figure 9] This figure illustrates a method for manufacturing a coil component according to a second embodiment. [Figure 10] This figure illustrates a method for manufacturing a coil component according to a second embodiment. [Figure 11] This is a perspective view of a coil component according to the third embodiment. [Figure 12] This is a perspective view of the coil and insulating member constituting the coil component according to the third embodiment. [Figure 13] This is a perspective view of a coil component according to the fourth embodiment. [Figure 14] This is a perspective view of the coil and insulating member constituting the coil component according to the fourth embodiment. [Figure 15] This is a cross-sectional view of a coil component according to the fifth embodiment. [Figure 16] This is a cross-sectional view of a coil component according to the sixth embodiment. [Modes for carrying out the invention]

[0031] The embodiments will be described below with reference to the drawings.

[0032] In this specification, terms such as "sheet," "film," and "plate" are not distinguished from each other solely based on differences in name. Therefore, for example, "sheet" is a concept that includes components that could also be called films or plates.

[0033] Furthermore, in this specification, "sheet surface (board surface, film surface)" refers to the surface that coincides with the planar direction (surface direction) of the sheet-like member in question when viewed as a whole and in a broad sense.

[0034] <Wireless Power Transmission System> Figure 1 schematically shows a wireless power transmission system S to which coil components according to the embodiment described later may be applied. First, the wireless power transmission system S (hereinafter abbreviated as power transmission system S) will be explained with reference to Figure 1.

[0035] The power transmission system S comprises a power transmission device 1 and a power receiving device 2. The power transmission device 1 includes a coil component 10 and a high-frequency current supply unit 1A. The coil component 10 in the power transmission device 1 functions as a power transmission coil. The high-frequency current supply unit 1A supplies high-frequency current to the coil component 10 as a power transmission coil.

[0036] The power receiving device 2 includes a coil component 10 and a conversion unit 2A. The coil component 10 in the power receiving device 2 functions as a power receiving coil. The conversion unit 2A shapes the high-frequency current generated in the coil component 10. The conversion unit 2A has a rectifier circuit and the like that converts the high-frequency current into a DC current.

[0037] When transmitting power wirelessly (contactlessly) from the power transmission device 1 to the power receiving device 2, the power transmission device 1 supplies a high-frequency current of a predetermined frequency to the coil component 10, which acts as a power transmission coil, from the high-frequency current supply unit 1A. At this time, a magnetic field is generated in the coil component 10 due to electromagnetic induction. Due to the influence of this magnetic field, a high-frequency current is generated in the coil component 10, which acts as a power receiving coil, in the power receiving device 2. The conversion unit 2A converts this high-frequency current into a DC current and supplies the converted DC current to, for example, a battery (not shown).

[0038] The power transmission system S shown in Figure 1 employs a magnetic resonance method as the power transmission method. However, the power transmission system S may also be configured as an electromagnetic induction power transmission system. Furthermore, the power transmission system S is configured as a system that wirelessly transmits power to an electric vehicle. In this case, the power transmission device 1 is installed on a road, parking lot, etc. The power receiving device 2 is installed in the electric vehicle.

[0039] However, the applications of the power transmission system S are not limited to power transmission to electric vehicles. For example, the power transmission system S may be used for power transmission to flying objects such as drones and robots. Furthermore, the power transmission system S may be used for power transmission to submersibles and exploration robots in the ocean. It should also be noted that the applications of the coil components according to this embodiment are not limited to wireless power transmission systems. For example, the coil components according to this embodiment may be used in transformers, DC-DC converters, antennas, and the like.

[0040] Each power transmission system S includes, as a coil component 10, one of the coil components according to each embodiment described later. Note that the same coil component from the same embodiment may be used in both the power transmission device 1 and the power receiving device 2. Alternatively, different coil components from different embodiments may be used in both the power transmission device 1 and the power receiving device 2. Furthermore, one of the power transmission device 1 and the power receiving device 2 may use a coil component from one embodiment, while the other uses a coil component of another type. The coil components according to each embodiment will be described below.

[0041] <First Embodiment> Figure 2 is a perspective view of the coil component 10A according to the first embodiment. Figure 3 is a cross-sectional view of the coil component 10A along the line III-III in Figure 2.

[0042] As shown in Figures 2 and 3, the coil component 10A comprises a coil 11, a case 20, a support column 30, a spacer member 40, a magnetic shielding member 44, an insulating member 46, a first connection terminal 51, and a second connection terminal 52.

[0043] Case 20 has a bottom wall portion 22, a side wall portion 23 rising from the bottom wall portion 22, and a top wall portion 24 provided at the tip of the side wall portion 23. In Figure 2, for the sake of explanation, the top wall portion 24 is shown in a separated state. The first connection terminal 51 and the second connection terminal 52 are simply indicated by dashed lines.

[0044] The case 20 houses the coil 11, spacer member 40, magnetic shield member 44, and insulating member 46. The support column 30 is connected to the top wall 24 as described later, but is located within the space enclosed by the bottom wall 22, side walls 23, and top wall 24. The spacer member 40, magnetic shield member 44, and insulating member 46 are arranged on the bottom wall 22 in this order. The spacer member 40, magnetic shield member 44, and insulating member 46 are each sheet-like and overlap. The spacer member 40 is interposed between the bottom wall 22 and the magnetic shield member 44 and insulating member 46 to support the magnetic shield member 44 and insulating member 46. The coil 11 is a planar coil as described later and is integrated with the sheet-like insulating member 46. As a result, the coil 11 is held away from the bottom wall 22.

[0045] The spacer member 40, magnetic shielding member 44, insulating member 46, and coil 11 are surrounded by the side wall portion 23 and covered from above by the top wall portion 24 in Figure 3.

[0046] The support column 30 is provided between the bottom wall portion 22 and the top wall portion 24, and the bottom wall portion 22 and the top wall portion 24 are positioned to sandwich the support column 30. In this embodiment, one end of the support column 30 is connected to the top wall portion 24, and the other end of the support column 30 is in contact with the bottom wall portion 22. As a result, the load received by the top wall portion 24 is transmitted to the side wall portion 23 and the support column 30, and the load received by the top wall portion 24 is supported by the side wall portion 23 and the support column 30. Note that in Figure 2, for the sake of explanation, the top wall portion 24 and the support column 30 are shown separated. The parts that make up the coil component 10A will be described in detail below.

[0047] (coil) Figure 4 is a perspective view of the coil 11 and the insulating member 46. Figure 5 is a plan view of the coil 11 and the insulating member 46. The coil 11 is spiral-shaped and made of a conductive material. In this embodiment, the coil 11 is made of copper, but the coil 11 can be made of any conductive material, such as aluminum. In Figure 5, dots are marked on the area of ​​the coil 11 for ease of explanation.

[0048] The coil 11 is plate-shaped; that is, the coil 11 is a planar coil. More specifically, the coil 11 is a planar coil made of non-Litz wire. As shown in Figure 3, the cross-sectional shape of the conductor in the direction perpendicular to the circumferential direction of the spiral shape of the coil 11 is rectangular.

[0049] In Figures 2 to 5, the symbol C indicates the central axis of the coil 11, passing through the center of the spiral shape of the coil 11. Hereinafter, when referring to the axial direction of the coil 11, it means the direction extending along the central axis C or the direction parallel to the central axis C. The direction perpendicular to the central axis C is called the radial direction.

[0050] The coil 11 includes a conductor 11E having a spiral shape. The conductor 11E includes a plurality of turned portions 12n. The plurality of turned portions 12n are arranged radially outward from the central axis C of the spiral shape. The plurality of turned portions 12n are connected so as to move radially outward from the central axis C, gradually moving away from the central axis C, thereby forming a spiral shape.

[0051] The turn section 12n has a shape in which the linear conductor portion does not form a ring but rotates 360 degrees around the central axis C. In the case of a so-called planar coil, both ends of the turn section 12n are offset in the radial direction. In a group of turn sections 12n, the radially inward end of one turn section 12n is connected to the radially outward end of another turn section 12n, and the other turn sections 12n extend away from the central axis C.

[0052] In turn section 12n, "n" represents a variable that takes a number from 1 corresponding to the number of turns in coil 11. Below, the turn section 12n closest to the central axis C may be referred to as turn section 121. Additionally, the turn section connected to the radially outer end of turn section 121 may be referred to as turn section 122, and the turn section connected to the radially outer end of turn section 122 may be referred to as turn section 123. In the examples in Figures 4 and 5, the number of turns is 9, and the multiple turn sections 12n are composed of 9 turn sections 121 to 129. Turn section 129 corresponds to the turn section located on the outermost periphery.

[0053] Furthermore, "inside the radial direction of a component" means a position closer to the central axis C than the component itself. Conversely, "outside the radial direction of a component" means a position further outward in the radial direction than the component itself. For example, "inside the radial direction of coil 11" means a position closer to the central axis C than the innermost turn portion 121. "Outside the radial direction of coil 11" means a position further outward in the radial direction than the outermost turn portion 129.

[0054] In the illustrated example, the first turn 12n from the radially inner side of the coil 11 is turn 121, and the second turn 12n from the radially inner side of the coil 11 is 122. The first turn 12n from the radially outer side of the coil 11 is turn 129, and the second turn 12n from the radially outer side of the coil 11 is 128. When describing the positional relationship between two members, they are sometimes referred to as the radially inner member and the radially outer member. In this case, the member closer to the central axis C of the two members corresponds to the radially inner member. Also, the member located radially further away from the radially inner member corresponds to the radially outer member.

[0055] In the following explanation, when describing matters common to each of the multiple turn sections 12n, they will generally be referred to as "turn section 12n".

[0056] In this embodiment, the turn section 12n is arranged in a rectangular shape. As a result, the shape of the coil 11 in plan view is also rectangular. The turn section 12n shown in Figure 5 is formed by connecting the first straight section 131n, the first corner section 132n, the second straight section 133n, the second corner section 134n, the third straight section 135n, the third corner section 136n, the fourth straight section 137n, the fourth corner section 138n, and the fifth straight section 139n in this order to form a rectangle. The starting end of the first straight section 131n and the ending end of the fifth straight section 139n are located on a reference line St that extends radially from the central axis C. The starting end of the first straight section 131n of the next turn section 12n is connected to the ending end of the fifth straight section 139n.

[0057] In the above symbols 131n to 139n, "n" also represents a variable that takes a number from 1 to the number of turns of the coil 11. Hereafter, for example, the above parts of the turn section 121 may be referred to as the first straight section 1311, the first corner section 1321, the second straight section 1331, the second corner section 1341, the third straight section 1351, the third corner section 1361, the fourth straight section 1371, the fourth corner section 1381, and the fifth straight section 1391.

[0058] To elaborate on the shape of the turn section 12n, the first corner section 132n connects the first straight section 131n and the second straight section 133n, which are separated from each other. The first straight section 131n, the first corner section 132n, and the second straight section 133n are connected in a curved manner. In this example, the first corner section 132n is arc-shaped, and the first straight section 131n extends along a straight line from one end of the first corner section 132n. The second straight section 133n extends along a straight line from the other end of the first corner section 132n.

[0059] Then, in the same manner as the first straight section 131n, the first corner section 132n, and the second straight section 133n, the second straight section 133n, the second corner section 134n, and the third straight section 135n are connected, the third straight section 135n, the third corner section 136n, and the fourth straight section 137n are connected, and the fourth straight section 137n, the fourth corner section 138n, and the fifth straight section 139n are connected.

[0060] Although the turn portion 12n shown in Figure 5 is rectangular in shape, the shape of the turn portion 12n is not particularly limited. For example, part or all of the turn portion 12n may have a circular shape. Also, the corner portions 132n, 134n, 136n, and 138n described above may be straight or be broken lines along a circular arc. In this specification and disclosure, the spiral shape refers to the shape of a spirally wound planar curve. The planar curve referred to here also includes planar patterns that are bent and connected in a broken line shape as shown in the figure. In other words, the spiral shape is a shape that is rotated around the central axis C of the coil 11 so that it is gradually positioned outward.

[0061] Furthermore, the number of pairs of radially adjacent turn portions 12n in the conductor 11E is 8, since the number of turns is 9. In this embodiment, these pairs of radially adjacent turn portions 12n include those where the gap width between them is constant and those where it is not.

[0062] More specifically, the width of the gap between the fourth turn portion 124 and the fifth turn portion 125 from the radially inward side of the coil 11 is not constant. This gap includes a first region B1 that is wider in the radial direction and a second region B2 that is narrower in the radial direction than the radial width of the first region B1. In the fourth turn portion 124 corresponding to the inward turn portion and the fifth turn portion 125 corresponding to the outward turn portion, for example, the first straight portion 1314 and the first straight portion 1315 are adjacent in the radial direction, and the second straight portion 1334 and the second straight portion 1335 are adjacent in the radial direction. Also, in the illustrated example, the first straight portion 1314 and the first straight portion 1315 are parallel, and the second straight portion 1334 and the second straight portion 1335 are parallel. Furthermore, the distance between one end and the other end of the first corner portion 1325 of the radially outward turn portion 125 of the two turn portions is smaller than the distance between one end and the other end of the first corner portion 1324 of the radially inward turn portion 124 of the two turn portions. More specifically, the curvature of the first corner portion 1324 of the radially inward turn portion 124 is smaller than the curvature of the first corner portion 1325 of the radially outward turn portion 125.

[0063] In the embodiments described above, the distance between the radially outward first straight portion 1315 and the radially inward first corner portion 1324 extends gradually away toward the midpoint of the first corner portion 1324. Similarly, the distance between the radially outward second straight portion 1335 and the radially inward first corner portion 1324 extends gradually away toward the midpoint of the first corner portion 1324. In this case, the distance between the radially inward first corner portion 1324 and the radially outward first corner portion 1325 becomes longer than, for example, the distance between the first straight portion 1314 and the first straight portion 1315. As a result, the distance between the radially inward first corner portion 1324 and the radially outward first corner portion 1325 becomes partially larger. The first region B1 is then formed between the radially inward first corner portion 1324 and the radially outward first corner portion 1325. Furthermore, the second region B2 is formed, for example, between the first straight section 1314 and the first straight section 1315.

[0064] In this example, the gap between the fourth turn section 124 and the fifth turn section 125 includes four second regions B1. Specifically, in addition to the first region B1 between the radially inward first corner section 1324 and the radially outward first corner section 1325, a first region B1 is formed between the second corner section 1344 and the second corner section 1345, a first region B1 is formed between the third corner section 1364 and the third corner section 1365, and a first region B1 is formed between the fourth corner section 1384 and the fourth corner section 1385. The second support column 32 of the support column 30, which will be described later, passes through each of the first regions B1. Note that the first regions B1 and the second regions B2 may be formed between other pairs of turn sections 12n other than the pair of the fourth turn section 124 and the fifth turn section 125.

[0065] Furthermore, in the conductor 11E, the width of the gap between a certain pair of adjacent turn portions 12n is constant, but it may differ in size from the constant gap between other pairs of adjacent turn portions 12n.

[0066] Specifically, between the first to fourth turn sections 121-124 from the radially inward side of the coil 11, the gap between all adjacent pairs of turn sections 12n is constant. Similarly, between the fifth to ninth turn sections 125-129 from the radially inward side of the coil 11, the gap between all adjacent pairs of turn sections 12n is constant. However, the gap between adjacent pairs of turn sections 12n that is constant in the five turn sections 125-129 from the radially inward side is smaller than the gap between adjacent pairs of turn sections 12n that is constant in the four turn sections 121-124 from the first to fourth turn sections from the radially inward side.

[0067] In other words, in this embodiment, the gap between adjacent turn portions 12n located at a position greater than the value obtained by dividing the number of turns n of the coil 11 by 2 is smaller than the gap between adjacent turn portions 12n located at a position less than the value obtained by dividing the number of turns n by 2. The size of the gap may be determined by comparing the value obtained by dividing the total area of ​​the gaps between all pairs of adjacent turn portions 12n located at a position greater than the value obtained by dividing the total area of ​​the gaps between all pairs of adjacent turn portions 12n located at a position less than the value obtained by dividing the total area of ​​the gaps between all connected turn portions located at a position less than the value obtained by dividing the gaps between all connected turn portions located at a position less than the value obtained by dividing the gaps between all connected turn portions located at a position less than the value obtained by dividing the gaps between all connected turn portions located at a position less than the value obtained by dividing the gaps between all connected turn portions located at a position less than the value obtained by dividing the gaps between all connected turn portions located at a position less than the value obtained by dividing the gaps between all connected turn portions located at a position less connected

[0068] The coil 11 described above is formed, for example, by punching a spiral shape out of a copper plate. Alternatively, the coil 11 can also be formed by etching a spiral shape out of copper foil. In this case, the coil 11 can be formed with a complex spiral pattern. However, etching is time-consuming in ensuring the thickness of the coil 11 that is capable of transmitting high power. Therefore, punching is preferable from the viewpoint of manufacturing efficiency.

[0069] Furthermore, the thickness of the conductor 11E in the coil 11, in other words, the thickness of the turn portion 12n, may be, for example, 0.2 mm or more and 1.0 mm or less. Also, the radius of the coil 11 (the distance from the central axis C to the part furthest in the radial direction) may be 200 mm or more. When transmitting power to an electric vehicle using a magnetic resonance method, it is desirable to be able to transmit power of 1 kW or more, preferably 5 kW or more, in the high-frequency current frequency range of 10 kHz to 200 kHz, particularly 79 kHz to 90 kHz. In this case, the thickness of the copper coil 11 is preferably 0.4 mm or more. However, if the thickness of the coil 11 is too large, the weight increases, which is undesirable, for example, for vehicle installation. Therefore, the thickness of the coil 11 may be, for example, 2.0 mm or less, 1.5 mm or less, or 1.0 mm or less.

[0070] The wire width of the conductor 11E in the coil 11 is not particularly limited. However, considering the ability to transmit power of 1 kW or more, preferably 5 kW or more, in the high-frequency current range of 79 kHz to 90 kHz, the wire width of the turn portion 12n may be 2 mm to 20 mm, 2 mm to 16 mm, 2 mm to 12 mm, or 2 mm to 8 mm. Note that the wire width refers to the distance between the inner and outer surfaces of the conductor 11E in a cross section perpendicular to the direction in which the conductor 11E circulates.

[0071] (case) As described above, case 20 has a bottom wall portion 22, a side wall portion 23, and a top wall portion 24. The bottom wall portion 22 is plate-shaped. The side wall portion 23 rises from the periphery of the bottom wall portion 22 and is located on the outer circumference of the coil 11. The side wall portion 23 surrounds the coil 11, the support column 30, the spacer member 40, the magnetic shield member 44, and the insulating member 46. The top wall portion 24 is connected to the tip of the side wall portion 23 and closes the side wall portion 23.

[0072] Case 20 is rectangular in plan view, and the bottom wall 22 and top wall 24 are also rectangular in plan view. The side wall 23 is rectangular in shape in plan view. However, the shape of case 20 in plan view is not particularly limited and may be other shapes such as circular. The coil component 10A may be incorporated into, for example, a power transmission device installed on the road surface. In a power transmission device installed on the road surface, it is assumed that vehicles may drive over the power transmission device. In this case, the top wall 24 covers and protects the coil 11 from above.

[0073] In this embodiment, as an example, the side wall portion 23 and the top wall portion 24 are integrally formed and made from the same material. The bottom wall portion 22 is formed separately from the side wall portion 23 and the top wall portion 24. The bottom wall portion 22 is made of a metallic material and may be conductive. Specifically, the bottom wall portion 22 is made of aluminum.

[0074] As described above, the coil component 10A is expected to be incorporated into a power transmission device installed on the road surface. In this case, it is preferable that the side walls 23 and top wall 24 have high rigidity and strength. For this reason, the material of the side walls 23 and top wall 24 may be fiber-reinforced plastic or the like. The material of the side walls 23 and top wall 24 is not particularly limited. However, in the coil component 10A, it is assumed that magnetism generated by the coil 11 or magnetism from other coils will be transmitted and received through the top wall 24. Therefore, a material that does not block magnetism is selected as the material forming the top wall 24. It is preferable that the top wall 24 has high rigidity and strength, and is non-conductive (insulating) and non-magnetic. Considering these points, fiber-reinforced plastic is a good material for the top wall 24. Insulation means that the volume resistivity is 10 10 This means it is greater than or equal to Ω·m. Non-magnetic means it does not exhibit magnetism.

[0075] The side wall portion 23 and the top wall portion 24 may be formed as a single piece, for example, by injection molding. Alternatively, the side wall portion 23 and the top wall portion 24 may be formed separately and then joined together by welding or other means.

[0076] The bottom wall portion 22 may be formed from a different material than the top wall portion 24 and the side wall portions 23. The material of the bottom wall portion 22 may be aluminum alloy, stainless steel, synthetic resin, etc. When the bottom wall portion 22 is formed from aluminum, aluminum alloy, stainless steel, etc., it also functions as a magnetic shield to prevent magnetic leakage to the outside. When the bottom wall portion 22 is formed from synthetic resin such as fiber-reinforced plastic, it may be advantageous in terms of productivity and weight reduction. However, the material of the bottom wall portion 22 is not particularly limited.

[0077] The manner in which the bottom wall portion 22 is attached to the side wall portion 23 is not particularly limited. The bottom wall portion 22 may be detachably attached to the side wall portion 23 by fastening means such as screws or bolts. The bottom wall portion 22 may be attached to the side wall portion 23 by welding or by adhesive.

[0078] (post) The support column 30 extends in the axial direction of the coil 11 and passes through the coil 11. The support column 30 is positioned so as to be sandwiched between the opposing top wall portion 24 and bottom wall portion 22. In this embodiment, one end of the support column 30 is connected to the inner surface of the top wall portion 24, and the other end of the support column 30 is in contact with the bottom wall portion 22.

[0079] As shown in Figure 2, the support column 30 includes a first support column 31 located radially inward of the innermost turn portion 121 and passing through the coil 11, and a second support column 32 located in the gap between adjacent turn portions 12n and passing through the coil 11. Specifically, the coil component 10A comprises one first support column 31 and four second support columns 32. However, the number of support columns 30 is not particularly limited.

[0080] The first support column 31 is rectangular in plan view. The four corners of the first support column 31 are chamfered in an arc shape. The turn section 121 is rectangular in shape by connecting the first straight section 1311, the first corner section 1321, the second straight section 1331, the second corner section 1341, the third straight section 1351, the third corner section 1361, the fourth straight section 1371, the fourth corner section 1381, and the fifth straight section 1391 in this order. The rectangular shape of the first support column 31 in plan view is parallel to the rectangular shape of the turn section 121 in plan view.

[0081] Furthermore, the four corner sections of the first support column 31 face the first corner section 1321, the second corner section 1341, the third corner section 1361, and the fourth corner section 1381, respectively. This layout allows the first support column 31 to be space-efficiently positioned radially inward of the turn section 121 located at the innermost circumference. This makes it possible to secure the largest possible cross-sectional area of ​​the first support column 31.

[0082] The shape of the first support column 31 is not particularly limited and may be cylindrical, elliptical, or otherwise. If the first support column 31 is cylindrical, the plan view shape of the turn section 121 is preferably circular. If the first support column 31 is elliptical, the plan view shape of the turn section 121 is preferably elliptical.

[0083] The second support column 32 passes through each of the four first regions B1 described above in the gap between the fourth turn portion 124 and the fifth turn portion 125. Preferably, the second support column 32 passes through the gap between adjacent turn portions 12n in the range from the second turn portion 122 from the radially inward side of the coil 11 to the second turn portion 128 from the radially outward side of the coil 11. However, the position of the second support column 32 is not particularly limited. In this embodiment, the second support column 32 passes only through the gap between the fourth turn portion 124 and the fifth turn portion 125, but a second support column 32 that passes through the gap between other turn portions may also be provided.

[0084] The four second support columns 32 are positioned at the same distance from the central axis C. When viewed in the axial direction of the coil 11, the case 20 is rectangular. In this case, it is preferable that the second support columns 32 are located on the diagonals of the case 20 when viewed in the axial direction of the coil 11. Alternatively, it is preferable that the second support columns 32 are located within the range enclosed by two line segments that extend from the diagonals of the case 20 rotated by ±10 degrees, preferably ±5 degrees, around the center of the case 20 when viewed in the axial direction of the coil 11. In this embodiment, the second support columns 32 are provided in the latter relationship.

[0085] In this embodiment, the central axis C of the spiral shape described above is determined as follows. First, starting from the radially inward end of the innermost turn portion 121, linear virtual turn portions similar in shape to the innermost turn portion 121 are sequentially drawn radially inward to form a spiral shape. Drawing is continued until a virtual turn portion that fits within a diameter of 1 cm can be drawn. Then, a line passing radially inward through the virtual turn portion that fits within a diameter of 1 cm, in a direction perpendicular to the circumferential and radial directions of the spiral shape, is determined as the central axis C.

[0086] As described above, the first region B1 is a region that is partially enlarged in the gap between the fourth turn 124 and the fifth turn 125. When the second support column 32 is passed through such a first region B1, the size of the second support column 32 can be increased. On the other hand, the second region B2 in the gap between the fourth turn 124 and the fifth turn 125 is smaller than the first region B1. This suppresses the reduction in the area of ​​the conductor 11E. Therefore, the deterioration of the coil characteristics due to the influence of the support column is suppressed.

[0087] In this embodiment, the second support column 32 is cylindrical, but the shape of the second support column 32 is not particularly limited. The second support column 32 may be a rectangular prism or an elliptical prism. The second support column 32 may also be a column with a triangular, semicircular, crescent, or fan-shaped cross-section.

[0088] Since the first support column 31 and the second support column 32 pass through the coil 11, it is preferable that they be made of a material that has little to no influence on the magnetism generated from the coil 11. Specifically, it is preferable that the first support column 31 and the second support column 32 have high rigidity and strength, and that they are non-conductive (insulating) and non-magnetic. Considering these points, the material of the first support column 31 and the second support column 32 may be fiber-reinforced plastic. However, the material of the first support column 31 and the second support column 32 is not particularly limited.

[0089] Furthermore, the first support column 31 and the second support column 32 are integrally connected to the top wall portion 24. In this embodiment, the first support column 31 and the second support column 32 and the top wall portion 24 are integrally molded. However, the first support column 31 and the second support column 32 and the top wall portion 24 may be formed separately and then joined by welding or the like. Also, the first support column 31 and the second support column 32 may be integrally connected to the bottom wall portion 22. Furthermore, the first support column 31 and the second support column 32 may be separated from the case 20, in which case they may be held in a state sandwiched between the bottom wall portion 22 and the top wall portion 24.

[0090] Furthermore, the size of the first support column 31 in plan view may be 10% or less of the area of ​​the coil 11 in plan view. The size of each second support column 32 in plan view may be 2.5% or less of the area of ​​the coil 11 in plan view. The area of ​​the coil 11 in plan view referred to here is the area enclosed by a closed shape formed by connecting the outer peripheral end 11B of the coil 11 to the outermost turn portion 129 at the shortest distance.

[0091] (Spacer member) The spacer member 40 is positioned so as to overlap the bottom wall portion 22. The spacer member 40 is a member that supports the coil 11 at a position away from the bottom wall portion 22. In this embodiment, the spacer member 40 supports the coil 11 via the magnetic shielding member 44 and the insulating member 46. The spacer member 40 is in contact with the bottom wall portion 22 and the magnetic shielding member 44.

[0092] The illustrated spacer member 40 is in the shape of a sheet or plate. In the portion of the bottom wall 22 where the spacer member 40 is not present, components such as capacitors used in constructing a power transmission device may be placed. However, the shape of the spacer member 40 is not particularly limited.

[0093] Furthermore, the material of the spacer member 40 is not particularly limited. The spacer member 40 may be made of metal, for example, or of resin.

[0094] (Magnetic shielding member) The magnetic shielding member 44 is provided to suppress magnetic transmission and / or leakage magnetic fields. The magnetic shielding member 44 is sheet-shaped and is sized to encompass the insulating member 46 and the coil 11 in a plan view. The magnetic shielding member 44 has through holes for passing the support columns 30 through. The through holes formed in the magnetic shielding member 44 overlap the radially inward direction of the turn portion 121 located at the innermost circumference of the coil 11 and each of the first regions B1 formed in the coil 11.

[0095] The magnetic shielding member 44 contains a magnetic material. The magnetic field generated by the coil component 10A spreads in all directions with respect to the central axis C of the coil 11. In this case, the magnetic shielding member 44, being magnetic, can orient the spreading magnetic flux lines toward the central axis C. Furthermore, if the magnetic field generated by the coil component 10A flows toward other surrounding components, it may adversely affect those components. Therefore, the magnetic shielding member 44 is provided to suppress the transmission of magnetic field lines. As a result, the magnetic shielding member 44 can suppress leakage magnetic fields that do not contribute to the generation of current.

[0096] The magnetic shielding member 44 preferably contains a soft magnetic material. More specifically, the magnetic shielding member 44 contains ferrite, preferably soft ferrite. The magnetic shielding member 44 may also contain a nanocrystalline magnetic material.

[0097] (Insulating material) The insulating member 46 overlaps with the coil 11 in the axial direction of the coil 11. In this state, the insulating member 46 is integrated with the coil 11. The insulating member 46 is sheet-like and is sized to encompass the coil 11 in a plan view.

[0098] As shown in Figures 3 to 5, the insulating member 46 has a spiral-shaped recess 46g corresponding to the spiral shape of the coil 11. The recess 46g is spiral-shaped when viewed in the axial direction of the coil 11 and is recessed in the axial direction of the coil 11, in other words, in the thickness direction of the insulating member 46. At least a portion of the coil 11 is housed within the recess 46g with its spiral shape aligned with the spiral shape of the recess 46g. More specifically, the recess 46g houses the entire conductor 11E.

[0099] In this embodiment, the conductor 11E does not protrude from the recess 46g and is flush with the insulating member 46. However, a portion of the coil 11 may be housed within the recess 46g so that a portion of the coil 11 protrudes from the recess 46g. Alternatively, the insulating member 46 may not have a recess 46g formed in it, and the coil 11 may be provided on the flat surface of the insulating member 46. Furthermore, the conductor 11E may be embedded in the insulating member 46 without being exposed to the outside.

[0100] The insulating member 46 is welded to the coil 11 in the recess 46g. That is, the coil 11 and the recess 46g are joined by an anchoring effect. The coil 11 and the insulating member 46 are integrated, for example, by hot pressing. At this time, a part of the insulating member 46 enters into the recess on the surface of the coil 11 and then hardens. As a result, the coil 11 and the recess 46g are welded together, and the insulating member 46 becomes integrated with the coil 11.

[0101] In this embodiment, the insulating member 46 contains a glass fiber-reinforced epoxy resin. That is, the insulating member 46 is formed from a material containing epoxy resin as a thermosetting resin (thermosetting material) and glass fibers. When the coil 11 and the insulating member 46 are integrated by hot pressing, the coil 11 is pressed into the forming material of the insulating member 46, forming a spiral-shaped recess 46g. In this case, if the forming material of the insulating member 46 is a glass fiber-reinforced epoxy resin, the epoxy resin softens and flows along the side surface of the coil 11, forming the recess 46g. In this case, the glass fibers suppress excessive flow of the epoxy resin.

[0102] For the reasons stated above, the insulating member 46 and its forming material are preferably made of glass fiber-reinforced epoxy resin. However, the insulating member 46 and its forming material are not particularly limited. For example, they do not need to contain glass fibers. Carbon fibers or the like may be used instead of glass fibers. Polyimide (thermoplastic resin) may be used instead of epoxy resin.

[0103] Furthermore, as shown in Figures 4 and 5, the insulating member 46 has through holes 46t formed therein for passing through the support columns 30. The through holes 46t formed in the insulating member 46 overlap the radially inward direction of the turn portion 121 located at the innermost circumference of the coil 11 and each of the first regions B1 formed in the coil 11. Specifically, the through holes 46t include a first through hole 46t1 that overlaps the radially inward direction of the turn portion 121 and a second through hole 46t2 that overlaps the first region B1. The first through hole 46t1 is rectangular in plan view. The second through hole 46t2 is circular. Note that the holes formed in the magnetic shielding member 44 may have the same shape as the corresponding through holes 46t.

[0104] Furthermore, as shown in Figure 3, the insulating member 46 and the coil 11 integrated with the insulating member 46 are separated from the inner surface of the top wall portion 24 of the case 20. This prevents the load on the top wall portion 24 from being transmitted to the coil 11, thereby protecting the coil 11. However, the coil 11 and / or the insulating member 46 may be in contact with the inner surface of the top wall portion 24.

[0105] (Connection terminals) As shown in Figure 2, the first connection terminal 51 is connected to the inner circumference end 11A of the coil 11. The second connection terminal 52 is connected to the outer circumference end 11B of the coil 11. In this embodiment, the lead portion connected to the radially inner end of the turn portion 121 in the conductor 11E forms the inner circumference end 11A of the coil 11. The lead portion connected to the radially outer end of the turn portion 129 forms the outer circumference end 11B of the coil 11. The first connection terminal 51 and the second connection terminal 52 can be used, for example, when connecting to a high-frequency current supply unit 1A or a conversion unit 2A. The connection between the first connection terminal 51 and the inner circumference end 11A and the connection between the second connection terminal 52 and the outer circumference end 11B are performed by ultrasonic bonding. However, the connection method is not limited, and for example, connection by conductive adhesive may be employed.

[0106] (Applications of coil components) The coil component 10A according to this embodiment can be used, for example, as a power transmission coil in the power transmission device 1 of the wireless power transmission system S described above, and can also be used as a power receiving coil in the power receiving device 2.

[0107] When a coil component 10A is used as a power transmission coil, the first connection terminal 51 and the second connection terminal 52 are connected to a high-frequency current supply unit 1A or an AC power source as shown in Figure 1. When a high-frequency current is supplied to the coil component 10A, the current can be passed from the first connection terminal 51 to the coil 11, and then from the second connection terminal 52 to the high-frequency current supply unit 1A or the AC power source. Alternatively, the current can be passed from the second connection terminal 52 to the coil 11, and then from the first connection terminal 51 to the high-frequency current supply unit 1A or the AC power source. This makes it possible to generate a magnetic field including magnetic field lines along the central axis of the coil 11.

[0108] On the other hand, when using coil component 10A as the power receiving coil, a high-frequency current can be generated in the coil 11 by receiving a magnetic field including magnetic field lines along the central axis of the coil 11. This high-frequency current can then be supplied to an external device from the first connection terminal 51 or the second connection terminal 52.

[0109] (Effects / Actions) The coil component 10A described above comprises a coil 11, a case 20 which is a housing member for housing the coil 11, and one or more support columns 30 that extend in the axial direction of the coil 11 and pass through the coil 11. The coil 11 includes a conductor 11E having a spiral shape, and the conductor 11E includes a plurality of turn portions 12n arranged radially outward from the central axis C of the spiral shape. At least one of the ends of the support columns 30 is connected to the inner surface of the case 20, or in contact with the inner surface of the case 20, or away from the inner surface of the case 20 and facing the inner surface. In this embodiment, one end of the support column 30 is connected to the inner surface of the top wall portion 24.

[0110] In this configuration, the load on case 20 can be supported by the support column 30, thus improving the strength of the coil component 10A compared to when case 20 alone bears the load. Furthermore, since the support column 30 is positioned to pass through the coil 11, the constraints on the coil size are relaxed compared to, for example, when load-bearing members such as support columns are provided radially outward of the coil 11. As a result, the reduction in coil area due to the influence of the support column 30 is suppressed, and thus the deterioration of coil characteristics can be prevented. Therefore, good strength and good coil characteristics can be ensured.

[0111] Furthermore, the support column 30 includes a first support column 31 located radially inward of the innermost turn portion 121. In this configuration, a large first support column 31 can be provided by utilizing the relatively large space radially inward of the innermost turn portion 121. This effectively improves the strength of the coil component 10A.

[0112] Furthermore, the support column 30 includes a second support column 32 that passes between adjacent turn sections 12n. In this configuration, by utilizing the gap between the turn sections 12n to provide the second support column 32, the influence of the second support column 32 on the coil characteristics can be suppressed. This makes it possible to effectively improve the strength of the coil component 10A while ensuring good coil characteristics.

[0113] Furthermore, it is preferable that the second support column 32 is located between the second turn portion 122 from the radially inward side of the coil 11 and the second turn portion 128 from the radially outward side of the coil 11. In this embodiment, the second support column 32 is located between the fourth turn portion 124 and the fifth turn portion 125 from the radially inward side of the coil 11. This configuration avoids the second support column 32 being positioned biased towards either the radially inward or radially outward side of the coil. This suppresses a localized decrease in strength and rigidity in the coil component 10A, thereby effectively improving the strength of the coil component 10A.

[0114] Furthermore, the gap between adjacent turn sections 124 and 125 through which the second support column 32 passes includes a first region B1 through which the second support column 32 passes, and a second region B2 whose radial width is narrower than the radial width of the first region B1. In this configuration, by making the first region B1 larger than the second region B2, the area of ​​the second support column 32 can be maximized. Also, by narrowing the second region B2, the reduction in the area of ​​the coil 11 can be suppressed. As a result, good coil characteristics can be ensured while effectively improving the strength of the coil component 10A.

[0115] Furthermore, in the turn section 124 and the turn section 125 corresponding to the adjacent inward turn section and the adjacent outward turn section that form the gap through which the second support column 32 passes, the first straight section 1314 and the first straight section 1315 are adjacent in the radial direction, and the second straight section 1334 and the second straight section 1335 are adjacent in the radial direction. Also, the distance between one end and the other end of the first corner section 1325 of the radially outward turn section 125 is smaller than the distance between one end and the other end of the first corner section 1324 of the radially inward turn section 124. As a result, the first region B1 is formed between the first corner section 1324 of the turn section 124 corresponding to the inward turn section and the first corner section 1325 of the turn section 125 corresponding to the outward turn section.

[0116] In this configuration, the first region B1 through which the second support column 32 passes can be made larger than the second region B2 while suppressing the abrupt shape change in the turn section 12n and thereby reducing electrical resistance. This is extremely advantageous in terms of ensuring good strength and good coil characteristics. In this embodiment, the radially adjacent first corner sections 1324 and 1325 are arc-shaped, and the curvature of the radially inner first corner section 1324 is smaller than the curvature of the outer first corner section 1325. In this case, the first region B1 through which the second support column 32 passes can be made larger than the second region B2 while suppressing the abrupt shape change in the turn sections 124 and 125 and thereby reducing electrical resistance in a simple form. Therefore, this is extremely advantageous in terms of productivity, ensuring good strength and good coil characteristics.

[0117] Furthermore, when viewed in the axial direction of the coil 11, the case 20 is rectangular in shape. When viewed in the axial direction of the coil 11, the second support column 32 is located either on the diagonal of the case 20 or within the range enclosed by line segments extending from positions obtained by rotating the diagonal of the case 20 by ±10 degrees around the center of the case 20. In this configuration, for example, the second support column 32 cooperates with the first support column 31 of the coil 11 and the case 20 to bear the load received by the case 20, thereby ensuring the desired strength while keeping the number of support columns 30 to a minimum. This is advantageous in terms of ensuring good strength.

[0118] Furthermore, the coil component 10A is further equipped with an insulating member 46 that contacts the coil 11 in the axial direction of the coil 11. The insulating member 46 has a through hole that overlaps with the gap between adjacent turn sections 124 and 125 through which the second support column 32 passes. The second support column 32 then passes through the through hole in the insulating member 46 and the gap between adjacent turn sections 124 and 125. In this configuration, the insulating member 46 reinforces the coil 11 and suppresses deformation, while the support column 30 improves the overall strength of the coil component 10A.

[0119] Furthermore, the coil 11 is separated from the inner surface of the case 20 to which the support column 30 is connected, in contact with, or facing. In this configuration, the transmission of load from the inner surface of the case 20 to the coil 11 can be suppressed, and the coil 11 can be protected. In this embodiment, the support column 30 is connected to the inner surface of the case 20. In this configuration, the case 20 and the support column 30 are integrated, resulting in improved handling and easier securing of high strength. The case 20 also has a side wall portion 23 that surrounds the outer circumference of the coil 11 and a top wall portion 24 that corresponds to an end wall that closes the side wall portion 23. The support column 30 is integrally connected to the top wall portion 24. In this configuration, the support column 30 and the side wall portion 23 can bear the load from the top wall portion 24. Therefore, the strength of the coil component 10A can be effectively improved.

[0120] <Second Embodiment> Next, a coil component 10B according to the second embodiment will be described. Figure 6 is a perspective view of the coil component 10B. Figure 7 is a perspective view of the coil 11 and insulating member 46 that constitute the coil component 10B. Components in this embodiment that are the same as those in the first embodiment are denoted by the same reference numerals, and redundant explanations are omitted.

[0121] As shown in Figures 6 and 7, the coil component 10B in this embodiment includes two types of second support columns 32 and 32'. Of the two types of second support columns 32 and 32', the second support column 32 has the same configuration as described in the first embodiment. On the other hand, the second support column 32' passes through the coil 11 at a different position than the second support column 32.

[0122] The second support column 32' passes between adjacent radially adjacent radially inner straight portion and radially outer straight portion of the radially adjacent turn portion 12n. As shown in Figure 7, the insulating member 46 has a third through hole 46t3 formed therein to allow the second support column 32' to pass through.

[0123] More specifically, the second support column 32' passes between adjacent straight sections in multiple adjacent turn sections 12n. In this embodiment, also referring to Figure 5, in all eight pairs of radially adjacent turn sections 12n from the radially inward, from the first to the ninth, the second support column 32' passes between the radially inward first straight section 131n and the radially outward first straight section 131n, between the radially inward second straight section 133n and the radially outward second straight section 133n, between the radially inward third straight section 135n and the radially outward third straight section 135n, and between the radially inward fourth straight section 137n and the radially outward fourth straight section 137n. The shape of the second support column 32' in plan view is a rectangle extending along the corresponding straight sections.

[0124] Figures 8 to 10 illustrate the manufacturing method of the coil component 10B. In this example, first, as shown in Figure 8, a coil intermediate 11M is prepared. The coil intermediate 11M has a shape in which a coil 11, more precisely a conductor 11E, is provided with a plurality of connecting parts 11C. The illustrated connecting parts 11C connect radially adjacent turn parts 12n in the conductor 11E. If the spiral shape of the coil 11 itself is formed by punching, the coil 11 is prone to deformation. The connecting parts 11C are provided to maintain the shape of the coil 11.

[0125] Next, as shown in Figure 9, the coil intermediate 11M and the insulating member intermediate 46M are integrated. The coil intermediate 11M and the insulating member intermediate 46M may be integrated by hot pressing. The insulating member intermediate 46M corresponds to the insulating member 46 before the through hole 46t is formed. The forming material of the insulating member intermediate 46M may be a material containing epoxy resin as a thermosetting resin (thermosetting material) and glass fibers. When hot pressing is performed, the forming material of the insulating member intermediate 46M and the coil intermediate 11M may be stacked on top of each other. Then, the forming material of the insulating member intermediate 46M and the coil intermediate 11M may be heated while being pressed together using a mold or press machine.

[0126] Next, as shown in Figure 10, the connecting portion 11C is removed. At this time, the connecting portion 11C is removed in the axial direction of the conductor 11E along with a part of the insulating member intermediate 46M. The coil 11 is formed by the removal of the connecting portion 11C. A first through hole 46t1, a second through hole 46t2, and a third through hole 46t3 are formed in the insulating member intermediate 46M. This forms the insulating member 46. The third through hole 46t3 is formed in the region of the insulating member intermediate 46M that includes the corresponding portion of the connecting portion 11C. The third through hole 46t3 is formed to be larger in size than the connecting portion 11C. The third through hole 46t3 extends along the straight portion between adjacent turn portions 12n. This allows for a larger size of the second support column 32'.

[0127] In other words, the third through-hole 46t3 is a hole formed when the connecting portion 11C is removed. In this embodiment, the third through-hole 46t3, which is formed due to the manufacturing process, is used as a hole through which the second support column 32' passes.

[0128] In the second embodiment described above, the number of support columns 30 increases, thereby improving the strength of the coil component 10B. Furthermore, by arranging the second support column 32' between the straight sections of adjacent turn sections 12n, it becomes easier to increase the length of the second support column 32', and the shape of the second support column 32' can also be simplified. This is advantageous in terms of ensuring good strength while reducing the effort required to manufacture the support columns.

[0129] Furthermore, the third through-hole 46t3 in the insulating member 46 through which the second support column 32' passes is a hole formed when the connecting portion 11C is removed. Therefore, the strength of the coil component 10B can be improved by effectively utilizing the hole formed due to the manufacturing process. If the second support column 32' is not placed in the third through-hole 46t3, the strength of the insulating member 46 may be improved by filling the third through-hole 46t3.

[0130] <Third Embodiment> Next, a coil component 10C according to the third embodiment will be described. Figure 11 is a perspective view of the coil component 10C. Figure 12 is a perspective view of the coil 11 and insulating member 46 that constitute the coil component 10C. Components in this embodiment that are the same as those in the first and second embodiments are denoted by the same reference numerals, and redundant explanations are omitted.

[0131] As shown in Figures 11 and 12, the coil component 10C in this embodiment comprises a first support column 31 and four second support columns 32. The positions and number of the first support column 31 and the second support columns 32 are the same as in the first embodiment. On the other hand, the shape of the second support columns 32 differs from that of the first embodiment.

[0132] More specifically, in this embodiment, the second support column 32 is formed in a semicircular shape in plan view. That is, the second support column 32 is formed as a columnar body with a semicircular cross-sectional shape in cross-section. The arcuate surface of the second support column 32 faces the radially outer corner portion of the adjacent turn portion 12n. The third through hole 46t3 in the insulating member 46 is also formed in a semicircular shape in plan view. The third through hole 46t3 overlaps with the first region B1.

[0133] In this embodiment, the second support column 32 is formed in a semicircular shape in plan view, which makes it easier to increase the size of the second support column 32 that passes through the first region B1. This is advantageous in terms of ensuring good strength in the coil component 10C.

[0134] <Fourth Embodiment> Next, a coil component 10D according to the fourth embodiment will be described. Figure 13 is a perspective view of the coil component 10D. Figure 14 is a perspective view of the coil 11 and insulating member 46 that constitute the coil component 10D. Components in this embodiment that are the same as those in the first to third embodiments are denoted by the same reference numerals, and redundant explanations are omitted.

[0135] As shown in Figures 13 and 14, the coil component 10D in this embodiment includes a first support column 31 similar to that in the first embodiment, and a plurality of second support columns 32' described in the second embodiment. On the other hand, no second support columns 32 are arranged in the first region B1 of the coil 11.

[0136] In this embodiment, reducing the number of through holes 46t in the insulating member 46 is advantageous in terms of ensuring the strength of the insulating member 46. Note that the first region B1 does not necessarily need to be formed in the coil 11.

[0137] <Fifth Embodiment> Next, a coil component 10E according to the fifth embodiment will be described. Figure 15 is a cross-sectional view of the coil component 10E. Components in this embodiment that are the same as those in the first to fourth embodiments are denoted by the same reference numerals, and redundant explanations are omitted.

[0138] As shown in Figure 15, in the coil component 10E of this embodiment, the conductor 11E in the coil 11 is embedded in the insulating member 46 in a state where it is not exposed to the outside. With this configuration, warping of the coil 11 can be effectively suppressed.

[0139] <Sixth Embodiment> Next, a coil component 10F according to the sixth embodiment will be described. Figure 16 is a cross-sectional view of the coil component 10F. Among the components in this embodiment, the first

[0140] As shown in Figure 16, in the coil component 10F of this embodiment, the coil 11 includes a first coil 11-1 and a second coil 11-2. The insulating member 46 has a three-layer structure and includes a first insulating member 46-1, a second insulating member 46-2, and a third insulating member 46-3. The first coil 11-1, the second coil 11-2, the first insulating member 46-1, the second insulating member 46-2, and the third insulating member 46-3 are integrated together. The conductors 11E contained in the first coil 11-1 and the second coil 11-2 are embedded in the insulating member 46 (46-1 to 46-3) in a state where they are not exposed to the outside. The first coil 11-1 and the second coil 11-2 overlap in the axial direction and are held apart in the axial direction. The first coil 11-1, more precisely, has its conductor 11E sandwiched between the first insulating member 46-1 and the second insulating member 46-2. The second coil 11-2, more precisely, has its conductor 11E sandwiched between the second insulating member 46-2 and the third insulating member 46-3. The first insulating member 46-1 is in contact with the magnetic shielding member 44.

[0141] The first coil 11-1 and the second coil 11-2 may be connected in series or in parallel. In Figure 16, the boundary between the first insulating member 46-1 and the second insulating member 46-2 is shown near the midpoint in the thickness direction of the first coil 11-1. The boundary between the second insulating member 46-2 and the third insulating member 46-3 is shown near the midpoint in the thickness direction of the second coil 11-2. These boundaries may not be visible when the first insulating member 46-1, the second insulating member 46-2, and the third insulating member 46-3 are integrated, but they are clearly shown in Figure 16 for the sake of explanation.

[0142] With the above configuration, warping that may occur in the integrated structure of the first coil 11-1, the second coil 11-2, the first insulating member 46-1, the second insulating member 46-2, and the third insulating member 46-3 can be effectively suppressed. In addition, by increasing the total amount of coil material, the amount of heat generated per unit area of ​​the coil can be suppressed.

[0143] <Evaluation of coil characteristics> Next, we will explain the results of evaluating the coil characteristics of the coil component 10A according to the first embodiment and the coil characteristics of the coil component according to the comparative example. In the evaluation, a high-frequency current of 85 Hz was supplied to each coil component, and the inductance Ls and impedance Rs at that time were measured. Then, the Q value was calculated from the measured Ls and Rs.

[0144] In the coil component 10A according to the first embodiment, the gap between the fourth turn portion 124 and the fifth turn portion 125 from the radially inward side of the coil 11 is partially enlarged in the first region B1. In the comparative example, the shapes of the first to fourth turn portions from the radially inward side of the coil are the same as in the coil component 10A. On the other hand, the width of the gap between the fourth turn portion and the fifth turn portion is constant. In the comparative example, from the first turn portion to the ninth turn portion, each turn portion forms a spiral shape while maintaining a constant gap width between the turn portions. The evaluation results are shown in Table 1 below.

[0145] [Table 1]

[0146] The inductance Ls of the coil component 10A in this embodiment is lower than that of the comparative example. This is thought to be due to the reduced area of ​​the coil 11 compared to the comparative example. On the other hand, the impedance Rs of the coil component 10A is lower than that of the comparative example. This is thought to be because the resistance increase due to the proximity effect is suppressed in this embodiment. When comparing the Q values, it can be evaluated that there is no difference between the two. From these results, it was inferred that in this embodiment, the gap between the turned portions 12n widened for the support column 30 contributes to suppressing the resistance increase due to the proximity effect. This was inferred to provide the effect of improving the strength of the coil component 10A by means of the support column 30 while suppressing the deterioration of the coil characteristics.

[0147] While embodiments of this disclosure have been described above, various modifications may be made to the embodiments described above. Such modifications may also fall within the technical scope of this disclosure. [Explanation of Symbols]

[0148] S...Power transmission system 1... Power transmission equipment 1A…High-frequency current supply unit 2... Power receiving device 2A...Conversion section 10, 10A, 10B, 10C, 10D, 10E, 10F… Coil components 11… Coil 11A...Inner circumference end 11B...Outer edge 11C...Connection part 11E... Conductor 11M…Coil intermediate 12n, 121, 122, ..., 128, 129... Turn section 131n…1st straight line part 132n... First corner section 133n…Second straight line part 134n... Second corner section 135n...Third straight line part 136n... Third corner section 137n…4th straight line part 138n... Fourth corner section 139n…5th straight line part 20... cases 22...Bottom wall 23... Side wall section 24…Top wall part 30…post 31...1st pillar 32, 32'…Second pillar 40…Spacer member 44…Magnetic shielding member 46…Insulating material 46g…recess 46t1…1st through hole 46t2…Second through hole 46t3...Third through hole 46M... Insulating material intermediate 51…First connection terminal 52...Second connection terminal

Claims

1. A coil comprising a conductor having a spiral shape, wherein the conductor includes a plurality of turns arranged radially outward from the central axis of the spiral shape, A storage member for housing the aforementioned coil, The coil comprises one or more support columns that extend in the axial direction of the coil and pass through the coil, At least one of the ends of the support column is connected to the inner surface of the storage member, or in contact with the inner surface of the storage member, or away from the inner surface of the storage member and facing the inner surface, The one or more of the aforementioned support columns include a second support column that passes between the radially adjacent turn portions, The gap between the radially adjacent turn portions through which the second support column passes includes a first region through which the second support column passes and a second region whose radial width is narrower than the radial width of the first region. A coil component in which the radial dimension of the second support column is greater than the radial width of the second region.

2. The coil component according to claim 1, wherein the one or more support columns include a first support column located radially inward of the turn portion located at the innermost circumference.

3. The one or more support columns include a plurality of the second support columns, The coil component according to claim 1 or 2, wherein a plurality of first regions and a plurality of second regions are alternately positioned along the direction in which the turn portions extend, between radially adjacent turn portions through which a plurality of second support columns pass.

4. The coil component according to any one of claims 1 to 3, wherein the second support column is located between the second turn portion from the radially inward side of the coil and the second turn portion from the radially outward side of the coil.

5. Each of the radially adjacent turn portions that form a gap through which the second support column passes, the inner turn portion located radially inward and the outer turn portion located radially outward, each having a first straight portion and a second straight portion extending along a straight line, and a corner portion connecting the first straight portion and the second straight portion, The corner portion is arc-shaped, straight, or broken along an arc, the first straight portion extends straight from one end of the corner portion, and the second straight portion extends straight from the other end of the corner portion. The coil component according to any one of claims 1 to 4, wherein in the inner turn portion and the outer turn portion, each first straight portion is adjacent in the radial direction, each second straight portion is adjacent in the radial direction, the distance between the ends of the corner portion of the outer turn portion is smaller than the distance between the ends of the corner portion of the inner turn portion, and the first region is the region between the corner portion of the inner turn portion and the corner portion of the outer turn portion.

6. The coil component according to claim 5, wherein the corner portion of the inner turn portion and the corner portion of the outer turn portion are arc-shaped, and the curvature of the corner portion of the inner turn portion is smaller than the curvature of the corner portion of the outer turn portion.

7. When viewed in the axial direction of the coil, the housing member is rectangular in shape. The coil component according to any one of claims 1 to 6, wherein, when viewed in the axial direction of the coil, the second support column is located on the diagonal of the housing member, or within a range enclosed by line segments extending to positions obtained by rotating the diagonal of the housing member by ±10 degrees around the center of the housing member.

8. The coil is further provided with an insulating member that contacts the coil in the axial direction, The insulating member has a second through-hole that overlaps with the gap between the radially adjacent turn portions through which the second support column passes. The coil component according to any one of claims 1 to 7, wherein the second support column passes through the second through hole and the gap.

9. The one or more support columns include a third support column that passes between the radially adjacent turn portions, Each of the radially adjacent turn portions that form the gap through which the third support column passes, the inner turn portion located radially inward and the outer turn portion located radially outward, each has a straight portion extending along a straight line. The coil component according to any one of claims 1 to 8, wherein the third support column passes between the straight portion of the adjacent inward turn portion and the straight portion of the outward turn portion.

10. The invention further comprises an insulating member that contacts the coil in the axial direction of the coil, The insulating member has a third through-hole that overlaps with the gap between the radially adjacent turn portions through which the third support column passes. The coil component according to claim 9, wherein the third support column passes through the third through hole and the gap.

11. Each of the radially adjacent turn portions that form the gap through which the third support column passes, the inner turn portion located radially inward and the outer turn portion located radially outward, each has a straight portion extending along a straight line. The coil component according to claim 10, wherein the third through hole overlaps the gap between the straight portion of the adjacent inner turn portion and the straight portion of the outer turn portion.

12. The coil component according to any one of claims 1 to 11, wherein the coil is separated from the inner surface of the housing member to which the support column is connected, in contact with, or facing.

13. The storage member has a side wall portion that surrounds the outer circumference of the coil and a top wall portion that closes the side wall portion. The coil component according to any one of claims 1 to 12, wherein the support column is integrally connected to the top wall portion.

14. The coil component according to any one of claims 1 to 13, wherein the support column is separate from the storage member and is sandwiched between opposing portions on the inner surface of the storage member or sandwiched between the inner surface of the storage member and another member.

15. The coil component according to any one of claims 1 to 14, wherein the support column is nonmagnetic and insulating.

16. A power transmission device comprising a coil component according to any one of claims 1 to 15.

17. A power receiving device comprising a coil component according to any one of claims 1 to 15.

18. It comprises a power transmission device and a power receiving device, A power transmission system in which at least one of the power transmission device and the power receiving device comprises a coil component according to any one of claims 1 to 15.

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