Coil component

Abstract

[Problem] To provide a coil component capable of achieving both low resistance and high inductance in a first conductor and / or a second conductor. [Solution] A coil component 1 includes: a first conductor 10; a second conductor 20 located inside the first conductor 10 and disposed along the first conductor 10; and an element body 30 covering at least a part of each of the first conductor 10 and the second conductor 20, and having a bottom surface 31a and a top surface 31b located on the side opposite to the bottom surface along the height direction. The second conductor 20 has a second winding portion 21, and a pair of second mounting portions 25a that are continuous with both ends of the second winding portion 21 and are at least partially exposed from the bottom surface 31a. In a cross section perpendicular to the winding axis direction of the second winding portion 21, when the height of the second conductor 20 is equally divided into two in the height direction, and an inside region surrounded by a virtual straight line connecting both ends of the second winding portion 21 in the extension direction and the inner peripheral surface of the second winding portion 21 is divided into a first region on the top surface 31b side of the element body 30 and a second region on the bottom surface 31a side of the element body 30, the area of the first region is larger than the area of the second region.

Description

Coil component

[0001] The present disclosure relates to a magnetically coupled coil component.

[0002] For example, Patent Document 1 discloses a coil component having a core, a plate-like first conductor and a second conductor disposed inside the core as a magnetically coupled coil component. The first conductor and the second conductor are bent in a U shape. The second conductor overlaps the first conductor and is disposed inside the first conductor. The coil component of Patent Document 1 is suitable for an electronic circuit for high-current applications.

[0003] Japanese Patent Application Laid-Open No. 2022-066107

[0004] In this type of coil component, it may be required to reduce the resistance and increase the inductance of the first conductor and / or the second conductor. However, in order to reduce the resistance of the first conductor and / or the second conductor, if the thickness of the first conductor and / or the second conductor is increased, the inner diameter of the winding portion of the first conductor and / or the second conductor becomes smaller, and there is a problem that the inductance of the first conductor and / or the second conductor decreases.

[0005] The present disclosure provides a coil component capable of achieving both low resistance and high inductance of the first conductor and / or the second conductor.

[0006] A coil component according to one embodiment of the present disclosure comprises: a first conductor; a second conductor located inside the first conductor and arranged along the first conductor; and an element body covering at least a portion of each of the first and second conductors, having a bottom surface and a top surface located opposite to the bottom surface in the height direction, wherein the first conductor has a first winding portion and a pair of first mounting portions continuous with both ends of the first winding portion and at least partially exposed from the bottom surface, and the second conductor has a second winding portion and a pair of second mounting portions continuous with both ends of the second winding portion and at least partially exposed from the bottom surface, and in a cross section perpendicular to the winding axis direction of the second winding portion, when the height of the second conductor is bisected in the height direction, and the inner region enclosed by a virtual straight line connecting both ends in the extending direction of the second winding portion and the inner circumferential surface of the second winding portion is divided into a first region on the top surface side of the element body and a second region on the bottom surface side of the element body, the area of ​​the first region is larger than the area of ​​the second region.

[0007] Figure 1 is a perspective view of an example of a coil component of the first embodiment. Figure 2 is an exploded perspective view of the coil component shown in Figure 1. Figure 3 is a cross-sectional view of the coil component shown in Figure 1 along line III-III. Figure 4 is a side view of the second conductor shown in Figure 1. Figure 5 is a side view of the first conductor shown in Figure 1. Figure 6 is a cross-sectional view of an example of a coil component of the second embodiment. Figure 7 is a side view of the second conductor shown in Figure 6. Figure 8 is a side view of the first conductor shown in Figure 6. Figure 9 is a cross-sectional view of an example of a coil component of the third embodiment. Figure 10 is a side view of the second conductor shown in Figure 9. Figure 11 is a side view of the first conductor shown in Figure 9. Figure 12 is a perspective view of an example of a coil component of the fourth embodiment. Figure 13 is a cross-sectional view of a modified version of the coil component shown in Figure 3. Figure 14 is a cross-sectional view of a modified version of the coil component shown in Figure 3. Figure 15 is a perspective view of a modified version of the coil component shown in Figure 2. Figure 16 is a cross-sectional view of a modified version of the coil component shown in Figure 6.

[0008] The embodiments of this disclosure will be described below with reference to the drawings. Note that the illustrations are provided for illustrative purposes only to aid in understanding this disclosure, and the appearance and dimensional ratios may differ from those of the actual product. Furthermore, this disclosure is not limited to the embodiments described below.

[0009] (First Embodiment) The coil component 1 of the first embodiment shown in Figure 1 is a magnetically coupled coil component, and is mounted, for example, as a transformer or inductor in the power supply of various electrical equipment. The coil component 1 has a first conductor 10, a second conductor 20, and an element body 30.

[0010] The element body 30 is made of a composite material containing a magnetic material and a resin, and covers at least a portion of each of the first conductor 10 and the second conductor 20. The element body 30 has an outer core 40 and an inner core 50.

[0011] The outer core 40 is formed by various molding techniques such as resin molding, transfer molding, injection molding, and dry molding. The outer core 40 is formed, for example, by filling the cavity of a mold in which the first conductor 10, the second conductor 20, and the inner core 50 are arranged with a composite material, and then compressing and curing it.

[0012] The magnetic material constituting the element body 30 is not particularly limited, but is, for example, ferrite or a metallic magnetic material. Examples of ferrites include Ni-Zn ferrite and Mn-Zn ferrite. Examples of metallic magnetic materials include Fe-Ni alloy powder, Fe-Si alloy powder, Fe-Si-Cr alloy powder, Fe-Co alloy powder, Fe-Si-Al alloy powder, amorphous iron, etc. The resin constituting the element body 30 is not particularly limited, but is, for example, epoxy resin, phenolic resin, polyester resin, polyurethane resin, or polyimide resin. The element body 30 may be composed of a sintered metallic magnetic material.

[0013] The element body 30 has a bottom surface 31a, a top surface 31b, a first side surface 31c, a second side surface 31d, a third side surface 31e, and a fourth side surface 31f. The bottom surface 31a faces the top surface 31b, the first side surface 31c faces the third side surface 31e, and the second side surface 31d faces the fourth side surface 31f. As shown in Figure 3, the top surface 31b is located along the height direction of the element body 30, on the opposite side from the bottom surface 31a.

[0014] In Figure 1, etc., the X-axis is the axis along the direction in which the first side surface 31c and the third side surface 31e face each other. The Y-axis is the axis along the direction in which the second side surface 31d and the fourth side surface 31f face each other. The Z-axis is the axis along the direction in which the bottom surface 31a and the top surface 31b face each other. The X-axis, Y-axis, and Z-axis are perpendicular to each other. Hereafter, the positive direction of the Z-axis will be considered upward, and the negative direction of the Z-axis will be considered downward. The direction in the Z-axis direction will also be called the height direction.

[0015] In this disclosure, "equal" is not a concept that refers only to a state in which the physical quantities of multiple objects being compared are exactly equal, but also includes a state in which there is an error of ±Δ% (not particularly limited, but for example Δ = 7, 5, or 3) or less between the physical quantities of multiple objects being compared.

[0016] Furthermore, in this disclosure, "parallel" does not refer only to strictly parallel lines, but also includes a state in which there is an error of ±Δθ° (not particularly limited, but for example, Δθ = 3) or less from strictly parallel lines. Similarly, "perpendicular" does not refer only to strictly perpendicular lines, but also includes a state in which there is an error of ±Δθ° (not particularly limited, but for example, Δθ = 3) or less from strictly perpendicular lines.

[0017] The length of the element body 30 in the X-axis direction is not particularly limited, but for example, it is 3.0 mm to 20.0 mm. The length of the element body 30 in the Y-axis direction is not particularly limited, but for example, it is 3.0 mm to 40.0 mm. The length of the element body 30 in the Z-axis direction is not particularly limited, but for example, it is 3.0 mm to 20.0 mm.

[0018] The external shape of the element body 30 is a hexahedron (cuboid), but it may also be other polyhedra such as an octahedron, or a prism such as a cylinder. In this disclosure, the prism includes solids in which the base 31a and the apex 31b are not congruent, such as a frustoconical shape.

[0019] As shown in Figure 2, the first conductor 10 is made up of a plate-shaped conductor and has a first winding portion 11 and a pair of first mounting portions 15a and 15b that are continuous with both ends of the first winding portion 11. The material constituting the first conductor 10 is not particularly limited, but can be a metal such as copper, copper alloy, silver, or nickel. The first conductor 10 is formed, for example, by machining a metal plate. The thickness of the first conductor 10 (the length between the inner and outer surfaces of the first conductor 10) is not particularly limited, but can be, for example, 0.1 mm to 2.5 mm. When the coil component 1 is used as a coupled inductor, the first conductor 10 functions, for example, as a primary conductor.

[0020] The first winding section 11 is bent in a C-shape or U-shape, and the number of turns in the first winding section 11 is less than one. The winding axis direction of the first winding section 11 corresponds to the X-axis direction. Also, the direction of the straight line connecting both ends of the extending direction of the first winding section 11 (virtual straight line L4 in Figure 5) corresponds to the Y-axis direction. The maximum length of the first winding section 11 in the Y-axis direction is longer than the height of the first winding section 11, but may be equal to or less than the height of the first winding section 11.

[0021] The first winding portion 11 has a first upper portion 12 and first lateral portions 13a and 13b. As shown in Figure 3, the first upper portion 12 extends linearly in the Y-axis direction (a direction parallel to the virtual straight line L4 in Figure 5). However, in this disclosure, "linear" includes not only cases where the shape of the object is a strictly straight line, but also cases where it is a substantially straight line, such as a gentle curve or wavy line with a large radius of curvature.

[0022] The first upper portion 12 is covered by the element body 30 (outer core 40). However, when viewed from above, at least a part of the first upper portion 12 may be exposed from the element body 30. In this case, the height position of the upper surface of the first upper portion 12 may be equal to the height position of the top surface 31b of the element body 30, or it may be located above the height position of the top surface 31b.

[0023] The first lateral portion 13a is continuous with one end of the first upper portion 12 in the direction of extension, and the first lateral portion 13b is continuous with the other end of the first upper portion 12 in the direction of extension. In a cross-section perpendicular to the winding axis direction of the second winding portion 21, each of the first lateral portions 13a and 13b is inclined with respect to the first upper portion 12. Also, in a cross-section perpendicular to the winding axis direction of the first winding portion 11, each of the first lateral portions 13a and 13b extends linearly as a whole.

[0024] The first lateral portions 13a and 13b are inclined with respect to the first upper portion 12 such that the distance between the first lateral portion 13a and the first lateral portion 13b approaches each other as it moves toward the bottom surface 31a (Figure 1) of the element body 30.

[0025] As shown in Figure 5, the angle between each of the pair of first lateral portions 13a and 13b and the first upper portion 12 is acute. However, the angle between each of the pair of first lateral portions 13a and 13b and the first upper portion 12 is defined as the angle between a line that is virtually extended from the inner circumferential surface of each of the pair of first lateral portions 13a and 13b and a line that is virtually extended from the inner circumferential surface of the first upper portion 12.

[0026] The angle θ3 formed by the first lateral portion 13a and the first upper portion 12 is not particularly limited, but for example it is 10°≦θ3≦89°, 30°≦θ3≦70°, 40°≦θ3≦65°, or 45°≦θ3≦60°. The angle θ4 formed by the first lateral portion 13b and the first upper portion 12 is not particularly limited, but for example it is 10°≦θ4≦89°, 30°≦θ4≦70°, 40°≦θ4≦65°, or 45°≦θ4≦60°. In this embodiment, angle θ3 is equal to angle θ4, but may be different from angle θ4.

[0027] The first mounting portions 15a and 15b function as terminal electrodes for electrically connecting the first conductor 10 to the land pattern of a mounting substrate (not shown). The first mounting portions 15a and 15b extend in a direction parallel to the first upper portion 12 and away from each other. In a cross section perpendicular to the winding axis direction of the first winding portion 11, the first mounting portions 15a and 15b extend linearly as a whole. However, in other embodiments, the respective ends of the first mounting portions 15a and 15b may be bent upward.

[0028] As shown in Figure 3, the first mounting portions 15a and 15b are at least partially exposed from the bottom surface 31a of the element body 30. The first mounting portions 15a and 15b are connected to the land pattern of the mounting substrate, for example, by solder or conductive adhesive, through the portions exposed from the bottom surface 31a. In this embodiment, a portion of the first mounting portion 15a is exposed downward from the bottom surface 31a, but the entire first mounting portion 15a may be exposed downward from the bottom surface 31a. Similarly, a portion of the first mounting portion 15b is exposed downward from the bottom surface 31a, but the entire first mounting portion 15b may be exposed downward from the bottom surface 31a.

[0029] As shown in Figure 1, the second conductor 20 is located inside the first conductor 10. The second conductor 20 is positioned at least partially along the first conductor 10 and overlaps with the first conductor 10.

[0030] As shown in Figure 2, the second conductor 20 is made up of a plate-shaped conductor and has a second winding portion 21 and a pair of second mounting portions 25a and 25b that are continuous with both ends of the second winding portion 21. The material constituting the second conductor 20 is the same as the material constituting the first conductor 10, but may be different. The second conductor 20 is formed, for example, by machining a metal plate. The thickness of the second conductor 20 (the length between the inner and outer surfaces of the second conductor 20) is not particularly limited, but is, for example, 0.1 mm to 1 mm. When the coil component 1 is used as a coupled inductor, the second conductor 20 functions, for example, as a secondary conductor.

[0031] The second winding section 21 is bent in a C-shape or U-shape, and the number of turns in the second winding section 21 is less than one. The winding axis direction of the second winding section 21 corresponds to the X-axis direction. Also, the extension direction of the straight line connecting both ends of the second winding section 21 in the extending direction (virtual straight line L2 in Figure 4) corresponds to the Y-axis direction. The maximum length of the second winding section 21 in the Y-axis direction is longer than the height of the second winding section 21, but may be equal to or less than the height of the second winding section 21.

[0032] The second winding section 21 has a second upper section 22 and second lateral sections 23a and 23b. As shown in Figure 3, the second upper section 22 is arranged parallel to the first upper section 12. The second upper section 22 extends linearly in the Y-axis direction (a direction parallel to the virtual straight line L2 in Figure 4).

[0033] The second lateral portion 23a is continuous with one end of the second upper portion 22 in the direction of extension, and the second lateral portion 23b is continuous with the other end of the second upper portion 22 in the direction of extension. In a cross-section perpendicular to the winding axis direction of the second winding portion 21, each of the second lateral portions 23a and 23b is inclined with respect to the second upper portion 22. Also, in a cross-section perpendicular to the winding axis direction of the second winding portion 21, each of the second lateral portions 23a and 23b extends linearly as a whole. The second lateral portion 23a is arranged parallel to the first lateral portion 13a, and the second lateral portion 23b is arranged parallel to the first lateral portion 13b.

[0034] The second lateral portions 23a and 23b are inclined with respect to the second upper portion 22 such that the distance between the second lateral portion 23a and the second lateral portion 23b approaches each other as it moves toward the bottom surface 31a of the element body 30.

[0035] As shown in Figure 4, the angle between each of the pair of second lateral portions 23a and 23b and the second upper portion 22 is acute. However, the angle between each of the pair of second lateral portions 23a and 23b and the second upper portion 22 is defined as the angle between a line that is virtually extended from the inner circumferential surface of each of the pair of second lateral portions 23a and 23b and a line that is virtually extended from the inner circumferential surface of the second upper portion 22.

[0036] The angle θ1 formed by the second lateral portion 23a and the second upper portion 22 is not particularly limited, but for example it is 10°≦θ1≦89°, 30°≦θ1≦70°, 40°≦θ1≦65°, or 45°≦θ1≦60°. The angle θ2 formed by the second lateral portion 23b and the second upper portion 22 is not particularly limited, but for example it is 10°≦θ2≦89°, 30°≦θ2≦70°, 40°≦θ2≦65°, or 45°≦θ2≦60°. In this embodiment, angle θ1 is equal to angle θ2, but may be different from angle θ2.

[0037] Furthermore, as shown in Figures 4 and 5, angle θ1 is equal to angle θ3, but may be different from angle θ3. Also, angle θ2 is equal to angle θ4, but may be different from angle θ4.

[0038] The second mounting portions 25a and 25b function as terminal electrodes for electrically connecting the second conductor 20 to the land pattern of the mounting substrate (not shown). The second mounting portions 25a and 25b extend in a direction parallel to the second upper portion 22 and away from each other. In a cross section perpendicular to the winding axis direction of the second winding portion 21, the mounting portions 25a and 25b extend linearly as a whole. However, in other embodiments, the respective ends of the second mounting portions 25a and 25b may be bent upward.

[0039] As shown in Figure 3, the second mounting portions 25a and 25b are exposed from the bottom surface 31a of the element body 30. The second mounting portions 25a and 25b are connected to the land pattern of the mounting substrate, for example, by solder or conductive adhesive. In this embodiment, the entirety of the second mounting portion 25a is exposed downward from the bottom surface 31a, but a part of the second mounting portion 25a may be exposed downward from the bottom surface 31a. Similarly, the entirety of the second mounting portion 25b is exposed downward from the bottom surface 31a, but a part of the second mounting portion 25b may be exposed downward from the bottom surface 31a. The bottom surfaces of the second mounting portions 25a and 25b are located on the same plane as the bottom surfaces of the first mounting portions 15a and 15b.

[0040] At least one of the first conductor 10 and the second conductor 20 has an insulating layer 90 covering its surface. In this embodiment, the second conductor 20 has an insulating layer 90 covering its surface. The first conductor 10 does not have an insulating layer 90, but the first conductor 10 may also have an insulating layer 90 covering its surface. The material constituting the insulating layer 90 is not particularly limited, but may be polyester, polyesterimide, polyamide, polyamideimide, polyurethane, epoxy, epoxy-modified acrylic resin, etc.

[0041] The insulating layer 90 covers the outer circumferential surface, the inner circumferential surface, and the side surface connecting the outer and inner circumferential surfaces of each of the second upper portion 22, second lateral portion 23a, and second lateral portion 23b. The insulating layer 90 also partially covers each of the second mounting portions 25a and 25b. In the second mounting portion 25a, the portion that contributes to connection with the land pattern of the mounting substrate, i.e., the portion to which solder or conductive adhesive is attached (in the example shown in Figure 3, the bottom surface of the second mounting portion 25a), has the insulating layer 90 removed and is exposed. Similarly, in the second mounting portion 25b, the portion that contributes to connection with the land pattern of the mounting substrate, i.e., the portion to which solder or conductive adhesive is attached (in the example shown in Figure 3, the bottom surface of the second mounting portion 25b), has the insulating layer 90 removed and is exposed.

[0042] The first conductor 10 and the second conductor 20 are insulated from each other via an insulating layer 90. An adhesive layer may be formed between the first upper portion 12 and the second upper portion 22 to connect them. Alternatively, the first upper portion 12 may be in direct contact with the second upper portion 22. Alternatively, a gap may be formed between the first upper portion 12 and the second upper portion 22.

[0043] An adhesive layer may be formed between the first lateral portion 13a and the second lateral portion 23a, connecting the first lateral portion 13a and the second lateral portion 23a. Alternatively, the first lateral portion 13a may be in direct contact with the second lateral portion 23a. Alternatively, a gap may be formed between the first lateral portion 13a and the second lateral portion 23a.

[0044] An adhesive layer connecting the first side portion 13b and the second side portion 23b may be formed between the first side portion 13b and the second side portion 23b. Alternatively, the first side portion 13b may be in direct contact with the second side portion 23b. Alternatively, a gap may be formed between the first side portion 13b and the second side portion 23b.

[0045] As shown in FIG. 2, the inner core 50 has a bottom surface 51a, a top surface 51b, a first side surface 51c, a second side surface 51d, a third side surface 51e, and a fourth side surface 51f. The bottom surface 51a faces the top surface 51b, and the first side surface 51c faces the third side surface 51e. The second side surface 51d and the fourth side surface 51f are located on opposite sides in the Y-axis direction. The inner core 50 is disposed inside the second winding portion 21 (inside region 60 in FIG. 4).

[0046] In the present embodiment, the outer shape of the inner core 50 is a hexahedron, but it may be another polyhedron such as an octahedron. In a cross-section perpendicular to the winding axis direction of the second winding portion 21, the shape of the outer peripheral surface of the inner core 50 is not particularly limited. In the example shown in FIG. 3, the shape of the outer peripheral surface of the inner core 50 corresponds to the shape of the inner peripheral surface of the second winding portion 21 in a cross-section perpendicular to the winding axis direction of the second winding portion 21, and is trapezoidal.

[0047] The inner core 50 is engaged with the second winding portion 21 in a state of being disposed inside the second winding portion 21. In a cross-section perpendicular to the winding axis direction of the second winding portion 21, the outer peripheral surface of the inner core 50 extends along the inner peripheral surface of the second winding portion 21. That is, each of the second side surface 51d and the fourth side surface 51f is inclined at an acute angle with respect to the top surface 51b. The angle formed by each of the second side surface 51d and the fourth side surface 51f and the top surface 51b is equal to the angle formed by each of the pair of second side portions 23a and 23b and the second upper portion 22, but may be different from the said angle. In the Y-axis direction (the direction parallel to the virtual straight line L2 in FIG. 4), the width of the inner core 50 becomes narrower as it approaches the bottom surface of the element body 30. The material constituting the inner core 50 is the same as the material constituting the outer core 40, but may be different from the material constituting the outer core 40.

[0048] In other embodiments, in a cross-section perpendicular to the winding axis direction of the second winding portion 21, at least a part of the outer peripheral surface of the inner core 50 may not extend along the inner peripheral surface of the second winding portion 21. In this case, in a cross-section perpendicular to the winding axis direction of the second winding portion 21, the outer peripheral surface of the inner core 50 has a shape that does not correspond to the shape of the inner peripheral surface of the second winding portion 21. For example, in a cross-section perpendicular to the winding axis direction of the second winding portion 21, the shape of the outer peripheral surface of the inner core 50 may be a circular shape, an elliptical shape, a square shape, a rectangular shape, other polygonal shapes, or other shapes as a shape that does not correspond to the shape of the inner peripheral surface of the second winding portion 21.

[0049] As shown in FIG. 2, the length of the inner core 50 in the X-axis direction is equal to the length of each of the first conductor 10 and the second conductor 20 in the X-axis direction, but may be different from the length of each of the first conductor 10 and the second conductor 20 in the X-axis direction. The height of the inner core 50 is not particularly limited, but is, for example, 1 / 2 or more of the height of the second conductor 20.

[0050] As shown in FIG. 3, there is no adhesive layer between the top surface 51b of the inner core 50 and the second upper portion 22. However, if necessary, the top surface 51b may be adhered to the second upper portion 22 with an adhesive. Alternatively, a part of the outer core 40 may be filled between the top surface 51b and the second upper portion 22. Alternatively, at least a part of the top surface 51b may be in contact with the second upper portion 22.

[0051] There is no adhesive layer between the fourth side surface 51f of the inner core 50 and the second side portion 23a. However, if necessary, the fourth side surface 51f may be adhered to the second side portion 23a with an adhesive. Alternatively, a part of the outer core 40 may be filled between the fourth side surface 51f and the second side portion 23a. Alternatively, at least a part of the fourth side surface 51f may be in contact with the second side portion 23a.

[0052] There is no adhesive layer between the second side surface 51d and the second lateral portion 23b of the inner core 50. However, if necessary, the second side surface 51d may be bonded to the second lateral portion 23b with an adhesive. Alternatively, a portion of the outer core 40 may be filled between the second side surface 51d and the second lateral portion 23a. Alternatively, at least a portion of the second side surface 51d may be in contact with the second lateral portion 23a.

[0053] The bottom surface 51a of the inner core 50 is covered by the outer core 40 (the bottom surface 31a of the element body 30). In the example shown in Figure 3, a gap is formed between the bottom surface 31a and the second mounting portion 25a. A gap is also formed between the bottom surface 31a and the second mounting portion 25b. However, the bottom surface 31a may be in contact with the second mounting portions 25a and 25b.

[0054] As shown in Figure 4, in a cross section perpendicular to the winding axis direction of the second winding section 21, the line that bisects the height H1 of the second conductor 20 in the height direction (indicated by a dashed line) is defined as the bisector L1. Also, the line connecting the two ends of the second winding section 21 in the extending direction (indicated by a dashed line) is defined as the virtual line L2. For convenience, in this disclosure, the virtual line L2 is assumed to pass through the upper surfaces of the second mounting sections 25a and 25b (the surfaces facing the bottom surfaces of the second mounting sections 25a and 25b). Furthermore, the region enclosed by the virtual line L2 and the inner circumferential surface of the second winding section 21 (indicated by a dashed line) is defined as the inner region 60. Furthermore, when the inner region 60 is divided into a region on the top surface 31b side and a region on the bottom surface 31a side of the element body 30 (Figure 3) via the bisector L1, the region on the top surface 31b side (indicated by the dashed line) is designated as the first region 70, and the region on the bottom surface 31a side (indicated by the dashed line) is designated as the second region 80.

[0055] The bisector L1 and the imaginary line L2 are parallel to the Y-axis. The length along the Z-axis between the bisector L1 and the upper surface of the second upper part 22 is half the height H1 of the second conductor 20. The length along the Z-axis between the bisector L1 and the bottom surface of the second mounting part 25a or the second mounting part 25b is half the height H1 of the second conductor 20.

[0056] In this embodiment, the area S1 of the first region 70 is larger than the area S2 of the second region 80. That is, the ratio S1 / S2 of the area S1 of the first region 70 to the area S2 of the second region 80 is 1 < S1 / S2. The above ratio S1 / S2 is not particularly limited, but for example, it may be 1 < S1 / S2 ≤ 2, 1.1 ≤ S1 / S2 ≤ 1.8, or 1.2 ≤ S1 / S2 ≤ 1.6.

[0057] As shown in Figure 5, in a cross section perpendicular to the winding axis direction of the first winding section 11, the line that bisects the height H2 of the first conductor 10 in the height direction (indicated by a dashed line) is defined as the line bisector L3. Also, the line connecting the two ends of the first winding section 11 in the extending direction (indicated by a dashed line) is defined as the virtual line L4. For convenience, in this disclosure, the virtual line L4 is assumed to pass through the upper surfaces of the first mounting sections 15a and 15b (the surfaces facing the bottom surfaces of the first mounting sections 15a and 15b). Furthermore, the region enclosed by the virtual line L4 and the inner circumferential surface of the first winding section 11 (indicated by a dashed line) is defined as the inner region 60'. Furthermore, when the inner region 60' is divided into a region on the top surface 31b side and a region on the bottom surface 31a side of the element body 30 (Figure 3) via the bisector L3, the region on the top surface 31b side is designated as the first region 70', and the region on the bottom surface 31a side is designated as the second region 80'.

[0058] The bisector L3 and the imaginary line L4 are parallel to the Y-axis. The length along the Z-axis between the bisector L3 and the upper surface of the first upper part 12 is half the height H2 of the first conductor 10. The length along the Z-axis between the bisector L3 and the lower surface of the first mounting part 15a or the first mounting part 15b is half the height H2 of the first conductor 10.

[0059] In this embodiment, the area S3 of the first region 70' is larger than the area S4 of the second region 80'. That is, the ratio S3 / S4 of the area S3 of the first region 70' to the area S4 of the second region 80' is 1 < S3 / S4. The above ratio S3 / S4 is not particularly limited, but for example, it may be 1 < S3 / S4 ≤ 2, 1.1 ≤ S3 / S4 ≤ 1.8, or 1.2 ≤ S3 / S4 ≤ 1.6. Also, the above ratio S1 / S2 is equal to the above ratio S3 / S4, but may be different from the above ratio S3 / S4.

[0060] Next, the manufacturing method of the coil component 1 will be described with reference to Figure 2, etc. First, the first conductor 10, the second conductor 20, and the pre-formed inner core 50 shown in Figure 2 are prepared. Next, the second conductor 20 is placed on top of the first conductor 10 so that the second conductor 20 is positioned inside the first conductor 10. If necessary, the outer surface of the second winding portion 21 is bonded to the inner surface of the first winding portion 11.

[0061] Next, the pair of the first conductor 10 and the second conductor 20 are placed in the cavity of the mold. The inner core 50 is also placed inside the second conductor 20. Next, a composite material containing magnetic material and resin is filled into the cavity so that at least a portion of each of the first mounting portions 15a and 15b and at least a portion of each of the second mounting portions 25a and 25b are exposed, and the first winding portion 11 and the second winding portion 21 are embedded, thereby forming the outer core 40. This forms the element body 30 including the outer core 40 and the inner core 50. In this way, the coil component 1 shown in Figure 1 can be manufactured.

[0062] As shown in Figure 4, in the coil component 1 of this embodiment, in a cross section perpendicular to the winding axis direction of the second winding portion 21, the height of the second conductor 20 is divided in the height direction, and the inner region 60 enclosed by the imaginary straight line L2 connecting both ends in the extending direction of the second winding portion 21 and the inner circumferential surface of the second winding portion 21 is divided into a first region 70 on the top surface 31b side of the element body 30 (Figure 3) and a second region 80 on the bottom surface 31a side of the element body 30. In this case, the area of ​​the first region 70 is larger than the area of ​​the second region 80. When the area of ​​the first region 70 is larger than the area of ​​the second region 80, it is possible to increase the inner diameter of the first winding portion 11 (Figure 3) and / or the second winding portion 21 compared to when the area of ​​the first region 70 is equal to the area of ​​the second region 80, and the inductance of the first conductor 10 (Figure 3) and / or the second conductor 20 can be increased. Therefore, the thickness of the first conductor 10 and / or the second conductor 20 can be increased without reducing the inductance of the first conductor 10 and / or the second conductor 20. This makes it possible to achieve both low resistance and high inductance of the first conductor 10 and / or the second conductor 20.

[0063] As shown in Figure 3, the number of turns in each of the first winding section 11 and the second winding section 21 is less than one turn. Therefore, the desired inductance can be obtained for each of the first conductor 10 and the second conductor 20 with a simple configuration.

[0064] The first winding section 11 has a first upper section 12 extending in a direction parallel to the virtual straight line L2 (Figure 4) (Y-axis direction), and a pair of first lateral sections 13a and 13b that are continuous with both ends of the first upper section 12 and inclined with respect to the first upper section 12. The second winding section 21 has a second upper section 22 extending in a direction parallel to the virtual straight line L2, and a pair of second lateral sections 23a and 23b that are continuous with both ends of the second upper section 22 and inclined with respect to the second upper section 22. The angles between each of the pair of first lateral sections 13a and 13b and the first upper section 12 are acute angles, and the angles between each of the pair of second lateral sections 23a and 23b and the second upper section 22 are acute angles. When the angle between each of the pair of first lateral portions 13a and 13b and the first upper portion 12 is acute, it is possible to increase the inner diameter of the first winding portion 11 compared to when the angle between each of the pair of first lateral portions 13a and 13b and the first upper portion 12 is right angle, thereby increasing the inductance of the first conductor 10. As a result, the thickness of the first conductor 10 can be increased without reducing the inductance of the first conductor 10. This makes it possible to achieve both low resistance and high inductance of the first conductor 10. Furthermore, when the angle between each of the pair of second lateral portions 23a and 23b and the second upper portion 22 is acute, it is possible to increase the inner diameter of the second winding portion 21 compared to when the angle between each of the pair of second lateral portions 23a and 23b and the second upper portion 22 is right angle, thereby increasing the inductance of the second conductor 20. Therefore, the thickness of the second conductor 20 can be increased without reducing its inductance. This makes it possible to achieve both low resistance and high inductance in the second conductor 20.

[0065] The angle between each of the pair of first lateral portions 13a and 13b and the first upper portion 12 is between 40° and 65°, and the angle between each of the pair of second lateral portions 23a and 23b and the second upper portion 22 is between 40° and 65°. In this case, it is possible to effectively achieve both low resistance and high inductance for the first conductor 10 and the second conductor 20.

[0066] In a cross-section perpendicular to the winding axis direction of the first winding portion 11, the first upper portion 12 and the second upper portion 22 each extend in a straight line. Therefore, as shown in Figure 4, the area of ​​the first region 70 can be efficiently made larger than the area of ​​the second region 80, and the inductance of the first conductor 10 and / or the second conductor 20 can be effectively increased. In addition, the height of the coil component 1 can be reduced compared to the case where the first upper portion 12 and the second upper portion 22 each curve toward the top surface 31b of the element body 30.

[0067] As shown in Figure 3, in a cross-section perpendicular to the winding axis direction of the second winding portion 21, the first lateral portions 13a and 13b extend linearly as a whole. Similarly, in a cross-section perpendicular to the winding axis direction of the second winding portion 21, the second lateral portions 23a and 23b extend linearly as a whole. Therefore, the resistance of the first conductor 10 and / or the second conductor 20 can be effectively reduced.

[0068] The element body 30 further includes an inner core 50 that can be inserted into the inner region 60 (Figure 4) in the X-axis direction (the winding axis direction of the second winding section 21). In a cross-section perpendicular to the winding axis direction of the second winding section 21, the outer circumferential surface of the inner core 50 extends along the inner circumferential surface of the second winding section 21. Therefore, the shape of the outer circumferential surface of the inner core 50 corresponds to the shape of the inner circumferential surface of the second winding section 21, and the inner core 50 can be easily inserted into the inner region 60 along the winding axis direction of the second winding section 21.

[0069] As shown in Figure 4, in the direction parallel to the virtual line L2, the width of the inner core 50 narrows towards the bottom surface 31a of the element body 30. Therefore, when the inner core 50 is placed in the inner region 60, it is possible to prevent the inner core 50 from falling.

[0070] (Second Embodiment) The coil component 1A of the second embodiment shown in Figure 6 has the same configuration as the coil component 1 of the first embodiment, except for the points described below. Members that overlap with the coil component 1 of the first embodiment are denoted by the same reference numerals, and their detailed descriptions are omitted.

[0071] As shown in Figure 6, the coil component 1A has a first conductor 10A and a second conductor 20A. The first conductor 10A has a first winding portion 11A, and the first winding portion 11A has first lateral portions 13aA and 13bA. The first lateral portion 13aA differs from the first lateral portion 13a of the first embodiment in that it has a first base end portion 130a and a first tip end portion 131a. The first lateral portion 13bA differs from the first lateral portion 13b of the first embodiment in that it has a first base end portion 130b and a first tip end portion 131b.

[0072] The second conductor 20A has a second winding portion 21A, and the second winding portion 21A has second lateral portions 23aA and 23bA. The second lateral portion 23aA differs from the second lateral portion 23a of the first embodiment in that it has a second base end portion 230a and a second tip end portion 231a. The second lateral portion 23bA differs from the second lateral portion 23b of the first embodiment in that it has a second base end portion 230b and a second tip end portion 231b.

[0073] The first base end 130a is continuous with one end of the first upper portion 12 and is inclined at an obtuse angle with respect to the first upper portion 12. The first tip end 131a is continuous with the first base end 130a and is inclined with respect to the first base end 130a. In a cross-section perpendicular to the winding axis direction of the first winding portion 11, the first tip end 131a extends in a direction nonparallel to the height direction (Z-axis direction). Also, in a cross-section perpendicular to the winding axis direction of the first winding portion 11, the first base end 130a and the first tip end 131a each extend in a straight line.

[0074] The first base end 130b is continuous with the other end of the first upper portion 12 and is inclined at an obtuse angle with respect to the first upper portion 12. The first tip end 131b is continuous with the first base end 130b and is inclined with respect to the first base end 130b. In a cross section perpendicular to the winding axis direction of the first winding portion 11, the first tip end 131b extends in a direction nonparallel to the height direction (Z-axis direction). In a cross section perpendicular to the winding axis direction of the first winding portion 11, the first base end 130b and the first tip end 131b each extend in a straight line.

[0075] The second base end 230a is continuous with one end of the second upper portion 22 and is inclined at an obtuse angle with respect to the second upper portion 22. The second tip end 231a is continuous with the second base end 230a and is inclined with respect to the second base end 230a. In a cross-section perpendicular to the winding axis direction of the second winding portion 21A, the second tip end 231a extends in a direction nonparallel to the height direction (Z-axis direction). Also, in a cross-section perpendicular to the winding axis direction of the second winding portion 21A, the second base end 230a and the second tip end 231a each extend in a straight line.

[0076] The second base end 230b is continuous with the other end of the second upper portion 22 and is inclined at an obtuse angle with respect to the second upper portion 22. The second tip end 231b is continuous with the second base end 230b and is inclined with respect to the second base end 230b. In a cross-section perpendicular to the winding axis direction of the second winding portion 21A, the second tip end 231b extends in a direction nonparallel to the height direction (Z-axis direction). Also, in a cross-section perpendicular to the winding axis direction of the second winding portion 21A, the second base end 230b and the second tip end 231b each extend in a straight line.

[0077] As shown in Figure 7, in this embodiment as well, in a cross section perpendicular to the winding axis direction of the second winding portion 21A, when the height of the second conductor 20A is divided in the height direction, and the inner region 60 enclosed by the imaginary straight line L2 connecting both ends in the extending direction of the second winding portion 21A and the inner circumferential surface of the second winding portion 21A is divided into a first region 70 on the top surface 31b side of the element body 30 (Figure 6) and a second region 80 on the bottom surface 31a side of the element body 30, the area of ​​the first region 70 is larger than the area of ​​the second region 80.

[0078] Furthermore, as shown in Figure 8, in a cross-section perpendicular to the winding axis direction of the first winding portion 11A, when the height of the first conductor 10A is divided in the height direction, and the inner region 60' enclosed by a virtual straight line L4 connecting both ends in the extending direction of the first winding portion 11A and the inner circumferential surface of the first winding portion 11A is divided into a first region 70' on the top surface 31b side of the element body 30 (Figure 6) and a second region 80' on the bottom surface 31a side of the element body 30, the area of ​​the first region 70' is larger than the area of ​​the second region 80'.

[0079] Therefore, the same effects as in the first embodiment can be obtained in this embodiment as well. In addition, as shown in Figure 6, in this embodiment, the distance between one first base end 130a and the other first base end 130b increases as you move towards the bottom surface 31a of the element body 30. Also, the distance between one first tip end 131a and the other first tip end 131b increases as you move towards the bottom surface 31a of the element body 30. Also, the distance between one second base end 230a and the other second base end 230b increases as you move towards the bottom surface 31a of the element body 30. Also, the distance between one second tip end 231a and the other second tip end 231b increases as you move towards the bottom surface 31a of the element body 30. Therefore, the first base ends 130a and 130b are inclined at an obtuse angle with respect to the first upper portion 12. As a result, at the boundary between the first upper portion 12 and the first lateral portion 13aA or 13bA, the bending of the first conductor 10A is gentler compared to the first embodiment, and the DC resistance of the first conductor 10A can be reduced. In addition, the second base ends 230a and 230b are inclined at an obtuse angle with respect to the second upper portion 22. As a result, at the boundary between the second upper portion 22 and the second lateral portion 23aA or 23bA, the bending of the second conductor 20A is gentler compared to the first embodiment, and the DC resistance of the second conductor 20A can be reduced.

[0080] (Third Embodiment) The coil component 1B of the third embodiment shown in Figure 9 has the same configuration as the coil component 1A of the second embodiment, except for the points described below. Members that overlap with the coil component 1A of the second embodiment are denoted by the same reference numerals, and their detailed descriptions are omitted.

[0081] As shown in Figure 9, the coil component 1B has a first conductor 10B and a second conductor 20B. The first conductor 10B has a first winding portion 11B, and the first winding portion 11B has first lateral portions 13aB and 13bB. The first lateral portion 13aB differs from the first lateral portion 13aA of the second embodiment in that it has a first tip portion 131aB instead of a first tip portion 131a. The first lateral portion 13bB differs from the first lateral portion 13bA of the second embodiment in that it has a first tip portion 131bB instead of a first tip portion 131b.

[0082] The second conductor 20B has a second winding portion 21B, and the second winding portion 21B has second lateral portions 23aB and 23bB. The second lateral portion 23aB differs from the second lateral portion 23aA of the second embodiment in that it has a second tip portion 231aB instead of a second tip portion 231a. The second lateral portion 23bB differs from the second lateral portion 23bA of the second embodiment in that it has a second tip portion 231bB instead of a second tip portion 231b.

[0083] As shown in Figure 10, in this embodiment as well, in a cross section perpendicular to the winding axis direction of the second winding portion 21B, when the height of the second conductor 20B is divided in the height direction, and the inner region 60 enclosed by the imaginary straight line L2 connecting both ends in the extending direction of the second winding portion 21B and the inner circumferential surface of the second winding portion 21B is divided into a first region 70 on the top surface 31b side of the element body 30 (Figure 9) and a second region 80 on the bottom surface 31a side of the element body 30, the area of ​​the first region 70 is larger than the area of ​​the second region 80.

[0084] Furthermore, as shown in Figure 11, in a cross-section perpendicular to the winding axis direction of the first winding portion 11B, when the height of the first conductor 10B is divided in the height direction, and the inner region 60' enclosed by the imaginary straight line L4 connecting both ends in the extending direction of the first winding portion 11B and the inner circumferential surface of the first winding portion 11B is divided into a first region 70' on the top surface 31b side of the element body 30 (Figure 9) and a second region 80' on the bottom surface 31a side of the element body 30, the area of ​​the first region 70' is larger than the area of ​​the second region 80'.

[0085] Therefore, the same effects as in the first embodiment can be obtained in this embodiment as well. In addition, in this embodiment, as shown in Figure 9, the distance between one first base end 130a and the other first base end 130b approaches each other as one approaches the bottom surface 31a of the element body 30. Furthermore, one first tip end 131aB and the other first tip end 131bB extend parallel to the height direction (Z-axis direction). Furthermore, the distance between one second base end 230a and the other second base end 230b approaches each other as one approaches the bottom surface 31a of the element body 30. Furthermore, one second tip end 231aB and the other second tip end 231bB extend parallel to the height direction (Z-axis direction). Therefore, it becomes possible to adjust the area of ​​the second region 80' (Figure 11) according to the respective lengths of the first tip end 131aB and the second tip end 231aB, thereby optimizing the inductance of the first conductor 10B. Furthermore, the area of ​​the second region 80 (Figure 10) can be adjusted according to the respective lengths of the first tip portion 131bB and the second tip portion 231bB, thereby optimizing the inductance of the second conductor 20B.

[0086] (Fourth Embodiment) The coil component 1C of the fourth embodiment shown in Figure 12 has the same configuration as the coil component 1 of the first embodiment, except for the points described below. Members that overlap with the coil component 1 of the first embodiment are denoted by the same reference numerals, and their detailed descriptions are omitted.

[0087] As shown in Figure 12, the coil component 1C has a plurality of first conductors 10, a plurality of second conductors 20, and a plurality of inner cores 50. Inside the outer core 40, a plurality of pairs of first conductors 10 and second conductors 20 are spaced apart along the winding axis direction (X-axis direction) of the second winding portion 21.

[0088] Multiple inner cores 50 are each positioned inside the second winding portion 21 of multiple second conductors 20. In this embodiment, the multiple inner cores 50 are spaced apart along the winding axis direction of the second winding portion 21, but a single elongated inner core 50 may penetrate the inside of the second winding portion 21 of multiple second conductors 20.

[0089] In this embodiment as well, the same effects as in the first embodiment can be obtained. In addition, in this embodiment, multiple pairs of the first conductor 10 and the second conductor 20 are spaced apart along the winding axis direction of the second winding portion 21. When a coil component 1C having n pairs (where n is a natural number of 2 or more) of the first conductor 10 and the second conductor 20 is mounted in an electronic device, it contributes to miniaturization of the electronic device compared to when only n coil components 1 (Figure 1) having a pair of first conductor 10 and second conductor 20 are mounted in the electronic device.

[0090] This disclosure is not limited to the embodiments described above, and can be modified in various ways within the scope of this disclosure.

[0091] (1) As shown in Figure 13, the first lateral portions 13a and 13b may be smoothly curved inward. The second lateral portions 23a and 23b may also be smoothly curved inward.

[0092] (2) As shown in Figure 14, the first lateral portions 13a and 13b may be smoothly curved outwards. The second lateral portions 23a and 23b may also be smoothly curved outwards.

[0093] (3) The coil component 1 may be composed of a plurality of element bodies (pre-molded bodies) that are combined with each other. In the example shown in Figure 15, the element body 30a has a base portion 32a and outer leg portions 33a and middle leg portions 34a that protrude from the base portion 32a toward the element body 30b. The outer leg portion 33a is located on the outside of the first winding portion 11 of the first conductor 10. The outer leg portion 33a has a pair of side portions 330a and a top portion 331a. The pair of side portions 330a are located along the first lateral portions 13a and 13b. The top portion 331a is located along the first upper portion 12. The middle leg portion 34a is located on the inside of the second winding portion 21 of the second conductor 20.

[0094] The element body 30b has a base portion 32b and outer leg portions 33b and middle leg portions 34b that protrude from the base portion 32b toward the element body 30a. The outer leg portions 33b are located on the outside of the first winding portion 11 of the first conductor 10. The outer leg portions 33b have a pair of side portions 330b and a top portion 331b. The pair of side portions 330b are located along the first lateral portions 13a and 13b. The top portion 331b is located along the first upper portion 12. The middle leg portion 34b is located on the inside of the second winding portion 21 of the second conductor 20.

[0095] The element body may consist of two E-type cores combined with each other, an E-type core and an I-type core combined with each other, at least one U-type core and at least one I-type core combined with each other, or a plurality of I-type cores combined with each other.

[0096] (4) In the above modified example (3), the top portion 331a may be omitted from the element body 30a, and at least a part of the first upper portion 12 may be exposed when viewed from above. Alternatively, the top portion 331b may be omitted from the element body 30b, and at least a part of the first upper portion 12 may be exposed when viewed from above.

[0097] (5) In the first embodiment described above, the inner core 50 may be omitted from the element body 30 shown in Figure 2, and a part of the outer core 40 may be placed in the position of the inner core 50. In other words, the element body 30 may be made of the same material on the outside of the first winding portion 11 and on the inside of the second winding portion 21. The same applies to the second to fourth embodiments described above. The element body 30 in this modified example is molded as follows. For example, after placing a pair of first conductors 10 and second conductors 20 in the cavity of a mold, a composite material containing magnetic material and resin is poured into the cavity. Then, in addition to the outside of the first winding portion 11, the composite material is filled into the inside of the second winding portion 21 (the inner region 60 in Figure 4). Through the above steps, the element body 30 in this modified example can be molded.

[0098] (6) In the first embodiment described above, when viewed from above, at least a part of the first upper portion 12 may be exposed from the element body 30 (inner core 50). The same applies to the second to fourth embodiments and the modified example (5) described above.

[0099] (7) In the third embodiment described above, the second tip portions 231aB and 231bB shown in Figure 9 may be inclined with respect to the height direction (Z-axis direction), as long as the condition that the area of ​​the first region 70 shown in Figure 10 is larger than the area of ​​the second region 80 is met. Also, the first tip portions 131aB and 131bB shown in Figure 9 may be inclined with respect to the height direction (Z-axis direction), as long as the condition that the area of ​​the first region 70' shown in Figure 11 is larger than the area of ​​the second region 80' is met.

[0100] (8) As shown in Figure 16, the first tip portion 131a may have a first portion 131a1 and a second portion 131a2 that is inclined with respect to the first portion 131a1. The first tip portion 131b may have a first portion 131b1 and a second portion 131b2 that is inclined with respect to the first portion 131b1. The distance between one first portion 131a1 and the other first portion 131b1 approaches each other as one approaches the bottom surface 31a of the element body 30. The distance between one second portion 131a2 and the other second portion 131b2 increases as one approaches the bottom surface 31a of the element body 30. The angle between the first tip portion 131a (second portion 131a2) and the first mounting portion 15a is obtuse. Furthermore, the angle between the first tip portion 131b (second portion 131b2) and the first mounting portion 15b is obtuse. Therefore, at the boundary between the second portion 131a2 and the first mounting portion 15a, the bending of the first conductor 10A is gentler compared to the first embodiment, and the DC resistance of the first conductor 10A can be reduced. Also, at the boundary between the second portion 131b2 and the first mounting portion 15b, the bending of the first conductor 10A is gentler compared to the first embodiment, and the DC resistance of the first conductor 10A can be reduced.

[0101] This specification discloses the following:

[0102] [Note 1] A coil component comprising: a first conductor; a second conductor located inside the first conductor and arranged along the first conductor; and an element body covering at least a portion of each of the first and second conductors, having a bottom surface and a top surface located opposite to the bottom surface in the height direction, wherein the first conductor has a first winding portion and a pair of first mounting portions continuous with both ends of the first winding portion and at least partially exposed from the bottom surface, and the second conductor has a second winding portion and a pair of second mounting portions continuous with both ends of the second winding portion and at least partially exposed from the bottom surface, and in a cross section perpendicular to the winding axis direction of the second winding portion, when the height of the second conductor is bisected in the height direction, and the inner region enclosed by a virtual straight line connecting both ends in the extending direction of the second winding portion and the inner circumferential surface of the second winding portion is divided into a first region on the top surface side of the element body and a second region on the bottom surface side of the element body, the area of ​​the first region is larger than the area of ​​the second region. [Note 2] The coil component according to Note 1, wherein the number of turns in each of the first and second winding sections is less than one turn. [Note 3] The coil component according to Note 1 or 2, wherein the first winding section has a first upper section extending in a direction parallel to the imaginary straight line and a pair of first lateral sections continuous with both ends of the first upper section and inclined with respect to the first upper section, the second winding section has a second upper section extending in a direction parallel to the imaginary straight line and a pair of second lateral sections continuous with both ends of the second upper section and inclined with respect to the second upper section, the angle between each of the pair of first lateral sections and the first upper section is acute, and the angle between each of the pair of second lateral sections and the second upper section is acute. [Note 4] The coil component according to Note 3, wherein the angle between each of the pair of first lateral portions and the first upper portion is 40° or more and 65° or less, and the angle between each of the pair of second lateral portions and the second upper portion is 40° or more and 65° or less. [Note 5] The coil component according to Note 3 or 4, wherein in a cross section perpendicular to the winding axis, each of the first upper portion and the second upper portion extends in a straight line.[Note 6] The coil component according to Note 5, wherein in a cross section perpendicular to the winding axis, the first lateral portion extends linearly as a whole, and in a cross section perpendicular to the winding axis, the second lateral portion extends linearly as a whole. [Note 7] Each of the pair of first lateral portions has a first base end that is continuous with the first upper portion and inclined with respect to the first upper portion, and a first tip that is continuous with the first base end and inclined with respect to the first base end; Each of the pair of second lateral portions has a second base end that is continuous with the second upper portion and inclined with respect to the second upper portion, and a second tip that is continuous with the second base end and inclined with respect to the second base end; The distance between one first base end and the other first base end increases with respect to the bottom surface; The distance between one first tip and the other first tip is closer with respect to the bottom surface; The distance between one second base end and the other second base end increases with respect to the bottom surface; The distance between one second tip and the other second tip is closer with respect to the bottom surface; The coil component according to any one of Notes 3 to 7. [Note 8] Each of the pair of first lateral portions has a first base end that is continuous with the first upper portion and inclined with respect to the first upper portion, and a first tip that is continuous with the first base end and inclined with respect to the first base end; Each of the pair of second lateral portions has a second base end that is continuous with the second upper portion and inclined with respect to the second upper portion, and a second tip that is continuous with the second base end and inclined with respect to the second base end; the distance between one first base end and the other first base end approaches each other as it approaches the bottom surface; one first tip and the other first tip extend parallel to the height direction; the distance between one second base end and the other second base end approaches each other as it approaches the bottom surface; and one second tip and the other second tip extend parallel to the height direction.[Note 9] A coil component according to any one of Notes 1 to 8, wherein a plurality of pairs of the first conductor and the second conductor are spaced apart along the winding axis.

[0103] 1, 1A, 1B, 1C... Coil component 10, 10A, 10B... First conductor 11, 11A, 11B... First winding section 12... First upper section 13a, 13b, 13aA, 13bA, 13aB, 13bB... First lateral section 130a, 130b... First base end 131a, 131b, 131aB, 131bB... First tip section 131a1, 131b1... First part 131a2, 131b2... Second part 15a, 15b... First mounting section 20, 20A, 20B... Second conductor 21, 21A, 21B... Second winding section 22... Second upper section 23a, 23b, 23aA, 23bA, 23aB, 23bB... Second side part 230a, 230b... Second base end part 231a, 231b, 231aB, 231bB... Second tip part 25a, 25b... Second mounting part 30, 30a, 30b... Element body 31a... Bottom surface 31b... Top surface 31c to 31f... First side surface to fourth side surface 32a, 32b... Base portion 33a, 33b... Outer leg portion 330a, 330b... Side portion 331a, 331b... Top portion 34a, 34b... Middle leg portion 40... Outer core 50... Inner core 51a... Bottom surface 51b... Top surface 51c to 51f...first side surface to second side surface 60,60'...inner area 70, 70'...First region 80, 80'...Second region 90...Insulating layer

Claims

1. A coil component comprising: a first conductor; a second conductor located inside the first conductor and arranged along the first conductor; and an element body covering at least a portion of each of the first and second conductors, having a bottom surface and a top surface located opposite to the bottom surface in the height direction, wherein the first conductor has a first winding portion and a pair of first mounting portions continuous with both ends of the first winding portion and at least partially exposed from the bottom surface, and the second conductor has a second winding portion and a pair of second mounting portions continuous with both ends of the second winding portion and at least partially exposed from the bottom surface, wherein in a cross section perpendicular to the winding axis direction of the second winding portion, when the height of the second conductor is bisected in the height direction, and the inner region enclosed by a virtual straight line connecting both ends in the extending direction of the second winding portion and the inner circumferential surface of the second winding portion is divided into a first region on the top surface side of the element body and a second region on the bottom surface side of the element body, the area of ​​the first region is larger than the area of ​​the second region.

2. The coil component according to claim 1, wherein the number of turns in each of the first winding portion and the second winding portion is less than one turn.

3. The coil component according to claim 1 or 2, wherein the first winding portion has a first upper portion extending in a direction parallel to the imaginary straight line and a pair of first lateral portions continuous with both ends of the first upper portion and inclined with respect to the first upper portion, the second winding portion has a second upper portion extending in a direction parallel to the imaginary straight line and a pair of second lateral portions continuous with both ends of the second upper portion and inclined with respect to the second upper portion, the angle between each of the pair of first lateral portions and the first upper portion is acute, and the angle between each of the pair of second lateral portions and the second upper portion is acute.

4. The coil component according to claim 3, wherein the angle between each of the pair of first lateral portions and the first upper portion is 40° or more and 65° or less, and the angle between each of the pair of second lateral portions and the second upper portion is 40° or more and 65° or less.

5. The coil component according to claim 3, wherein in a cross section perpendicular to the winding axis, each of the first upper portion and the second upper portion extends in a straight line.

6. The coil component according to claim 5, wherein in a cross section perpendicular to the winding axis, the first lateral portion extends linearly as a whole, and in a cross section perpendicular to the winding axis, the second lateral portion extends linearly as a whole.

7. The coil component according to claim 3, wherein each of the pair of first lateral portions has a first base end continuous with the first upper portion and inclined with respect to the first upper portion, and a first tip end continuous with the first base end and inclined with respect to the first base portion; each of the pair of second lateral portions has a second base end continuous with the second upper portion and inclined with respect to the second upper portion, and a second tip end continuous with the second base end and inclined with respect to the second base portion; the distance between one first base end and the other first base end increases with respect to the bottom surface; the distance between one first tip end and the other first tip end increases with respect to the bottom surface; the distance between one second base end and the other second base end increases with respect to the bottom surface; and the distance between one second tip end and the other second tip end increases with respect to the bottom surface.

8. The coil component according to claim 3, wherein each of the pair of first lateral portions has a first base end continuous with the first upper portion and inclined with respect to the first upper portion, and a first tip portion continuous with the first base end and inclined with respect to the first base portion; each of the pair of second lateral portions has a second base end continuous with the second upper portion and inclined with respect to the second upper portion, and a second tip portion continuous with the second base end and inclined with respect to the second base portion; the distance between one first base end and the other first base end approaches each other as it approaches the bottom surface; one first tip portion and the other first tip portion extend parallel to the height direction; the distance between one second base end and the other second base end approaches each other as it approaches the bottom surface; and one second tip portion and the other second tip portion extend parallel to the height direction.

9. The coil component according to claim 1 or 2, wherein a plurality of pairs of the first conductor and the second conductor are spaced apart along the winding axis.

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