Coil component

Abstract

The present invention relates to a coil component. A difference between an inductance value obtained by a first wire and an inductance value obtained by a second wire becomes large. The first wire (30) has a portion extending in a spiral shape on a peripheral surface (11F) of a winding core portion (11) with a central axis as a rotation axis. The second wire (40) has a portion extending in a spiral shape on a radial outer side than the peripheral surface (11F) of the winding core portion (11) with the central axis as a center. The second wire (40) has an outer side portion (41) and an inner side portion (42). The inner side portion (42) extends in a spiral shape continuously on the peripheral surface (11F) of the winding core portion (11) in a range longer than 360 degrees. The outer side portion (41) extends in a spiral shape on a radial outer side than the inner side portion (42) with the central axis as a center. The inner side portion (42) is located between an Lth turn and an L+1th turn of the first wire (30).

Description

Technical Field

[0001] This invention relates to coil components. Background Technology

[0002] Patent Document 1 describes a coil component comprising a core portion having a central axis, a first flange portion, and a second flange portion. The core portion is prism-shaped. The first flange portion is connected to a first end of the core portion. The second flange portion is connected to a second end of the core portion on the opposite side of the first flange portion.

[0003] Furthermore, the coil component described in Patent Document 1 has four terminal electrodes. The first terminal electrode and the second terminal electrode are located on the surface of the first flange portion. The third terminal electrode and the fourth terminal electrode are located on the surface of the second flange portion.

[0004] Furthermore, the coil component described in Patent Document 1 includes a first wire and a second wire. A first end of the first wire is connected to a first terminal electrode. A second end of the first wire, opposite to the first end, is connected to a third terminal electrode. A first end of the second wire is connected to a second terminal electrode. A second end of the second wire, opposite to the first end, is connected to a fourth terminal electrode. The first and second wires extend spirally about the central axis of the winding core, radially outward from the winding core. Additionally, most of the second wire is located radially outward from the first wire.

[0005] Patent Document 1: Japanese Patent Application Publication No. 2020-126976

[0006] In the coil component described in Patent Document 1, the second wire is located radially outward from the first wire, centered on the central axis. In other words, the second wire is farther from the core than the first wire. Therefore, the leakage flux of the second wire is more likely to be greater than that of the first wire. When the leakage flux of the second wire is greater, the inductance value obtained by the second wire is less than that obtained by the first wire. As a result, the difference between the inductance value obtained by the first wire and the inductance value obtained by the second wire becomes larger. Thus, if the difference between the inductance values ​​obtained by the first wire and the second wire is large, there is a possibility that it will adversely affect the characteristics of the coil component. Summary of the Invention

[0007] To address the aforementioned issues, one aspect of this disclosure is to provide a coil component comprising: a core portion having a central axis; a first flange portion connected to a first end of the core portion along the central axis; a second flange portion connected to a second end of the core portion opposite to the first end; a first terminal electrode and a second terminal electrode located on the surface of the first flange portion; a third terminal electrode and a fourth terminal electrode located on the surface of the second flange portion; a first wire having a portion extending spirally about the central axis as a rotation axis on the circumferential surface of the core portion, the first end being connected to the first terminal electrode, and the second end opposite to the first end being connected to the third terminal electrode; and a second wire having a portion extending spirally about the central axis as a rotation axis on a portion closer to the central axis than the circumferential surface of the core portion. The portion extending radially outward from the axis center has a first end connected to the second terminal electrode, and a second end on the opposite side of the first end connected to the fourth terminal electrode. The second wire has an inner portion extending spirally over a range longer than 360 degrees on the circumferential surface of the core portion, and an outer portion extending spirally outward from the radially outward side than the inner portion. In the portion of the first wire wound around the core portion, the first turn closest to the first end of the first wire on the line of the first wire is designated as the first turn, and the last turn closest to the second end of the first wire on the line of the first wire is designated as the Mth turn. When L is set to an integer greater than or equal to 1 and less than or equal to M-1, the inner portion is located between the Lth turn and the L+1th turn of the first wire.

[0008] According to the above structure, the second wire has an inner portion. The distance between the inner portion and the core portion is smaller than that between the outer portion and the core portion. Therefore, the leakage flux of the inner portion is smaller than that of the outer portion. As a result, it is possible to suppress the decrease in the inductance value obtained by the second wire. Consequently, compared to the case where the second wire is composed only of the outer portion, it is possible to increase the inductance value obtained by the second wire.

[0009] Furthermore, the inner portion is located between the Lth turn and the (L+1th turn) of the first wire. Therefore, the distance between the Lth turn and the (L+1th turn) of the first wire sandwiching the inner portion is equal to the amount of the inner portion. As a result, the leakage flux of the first wire increases, thereby reducing the inductance value obtained by the first wire.

[0010] In this way, by reducing the inductance value obtained from the first wire and increasing the inductance value obtained from the second wire, the difference between the inductance value obtained from the first wire and the inductance value obtained from the second wire can be reduced.

[0011] According to one aspect of this disclosure, it is possible to suppress the increase in the difference between the inductance value obtained from the first wire and the inductance value obtained from the second wire. Attached Figure Description

[0012] Figure 1 This is a 3D view of the coil component.

[0013] Figure 2 This is a top view of the coil component.

[0014] Figure 3 It is along Figure 2 A partial sectional view of the coil component of line 3-3 in the image.

[0015] Figure 4 This is a partial cross-sectional view of the coil component of the comparative example.

[0016] Figure 5 This is a graph showing the mode switching characteristics of the coil component of the embodiment and the coil component of the comparative example.

[0017] Figure 6 This is a partial sectional view of the coil component in the modified example.

[0018] Figure 7 This is a partial sectional view of the coil component in the modified example.

[0019] Figure 8 This is a partial sectional view of the coil component in the modified example.

[0020] Figure 9 This is a partial sectional view of the coil component in the modified example.

[0021] Explanation of reference numerals in the attached figures

[0022] 10…coil component; 10C…core; 11…core portion; 11F…circumferential surface; 12…first flange portion; 13…recessed portion; 14…second flange portion; 15…recessed portion; 16…top plate; 21…first terminal electrode; 22…second terminal electrode; 23…third terminal electrode; 24…fourth terminal electrode; 30…first wire; 40…second wire; 41…outer portion; 42…inner portion; CA…central axis. Detailed Implementation

[0023] <An embodiment of the coil component>

[0024] The following describes one embodiment of the coil component. Furthermore, the components are sometimes shown enlarged for ease of understanding in the accompanying drawings. The dimensional ratios of the components may differ from the actual dimensional ratios or those in other drawings. Additionally, while shading lines are indicated in sectional views, some shading lines for certain components are sometimes omitted for clarity.

[0025] (Overall structure)

[0026] like Figure 1As shown, the coil component 10 includes a core portion 11. The core portion 11 is a quadrangular prism. Therefore, the core portion 11 has a central axis CA and extends in the direction along the central axis CA. In addition, the core portion 11 has a circumferential surface 11F surrounding the central axis CA.

[0027] Furthermore, in the following description, the axis extending along the direction of the central axis CA is designated as the first axis X. The axis orthogonal to the first axis X is designated as the second axis Y, and the axis orthogonal to both the first axis X and the second axis Y is designated as the third axis Z. In the cross-section of the core portion 11 orthogonal to the central axis CA, the axis extending parallel to any one of the four sides constituting the quadrilateral is designated as the second axis Y, and the axis orthogonal to both the central axis CA and the second axis Y is designated as the third axis Z. Moreover, one direction along the first axis X is designated as the first positive direction X1, and the other direction along the first axis X is designated as the first negative direction X2. Similarly, one direction along the second axis Y is designated as the second positive direction Y1, and the other direction along the second axis Y is designated as the second negative direction Y2. Furthermore, one direction along the third axis Z is designated as the third positive direction Z1, and the other direction along the third axis Z is designated as the third negative direction Z2.

[0028] The coil component 10 has a first flange portion 12 and a second flange portion 14. The first flange portion 12 is connected to the end of the winding core portion 11 in the first positive direction X1, that is, the first end. The first flange portion 12 protrudes radially outward from the circumferential surface 11F of the winding core portion 11, centered on the central axis CA.

[0029] The recess 13 is recessed at the end face of the first flange 12 in the third positive direction Z1. The recess 13 is located in the central portion of the first flange 12 along the second axis Y. The recess 13 is recessed throughout the entire range of the first flange 12 along the first axis X. Therefore, the two ends of the first flange 12 along the second axis Y form a shape that branches into two branches with respect to the recess 13.

[0030] The second flange portion 14 is connected to the end of the core portion 11 in the first negative direction X2, i.e., the second end. The second flange portion 14 has a shape that is symmetrical with the first flange portion 12 in the direction along the first axis X, with respect to the core portion 11. That is, the recessed portion 15, which is symmetrical in shape with the recessed portion 13 of the first flange portion 12, is also recessed at the end face of the second flange portion 14 in the third positive direction Z1.

[0031] The core portion 11, the first flange portion 12, and the second flange portion 14 constitute the core 10C of the coil component 10. The core 10C is made of a non-conductive material. The material of the core 10C is, for example, aluminum oxide, nickel-zinc ferrite, resin, or a mixture thereof.

[0032] The coil component 10 includes a top plate 16. The top plate 16 is connected to the end of the core 10C in the third negative direction Z2. The top plate 16 is rectangular in shape. The top plate 16 is mounted on the core 10C such that the end face of the first flange portion 12 in the third negative direction Z2 and the end face of the second flange portion 14 in the third negative direction Z2 are supported. The top plate 16 is made of the same material as the core 10C and together with the core 10C forms a closed magnetic circuit.

[0033] The coil component 10 includes a first terminal electrode 21, a second terminal electrode 22, a third terminal electrode 23, and a fourth terminal electrode 24.

[0034] The first terminal electrode 21 is located on the surface of the first flange portion 12. Specifically, the first terminal electrode 21 is located in the end face of the first flange portion 12 in the third positive direction Z1 within the range of the second positive direction Y1, which is closer to the recessed portion 13.

[0035] The second terminal electrode 22 is located on the surface of the first flange portion 12. Specifically, the second terminal electrode 22 is located in the end face of the first flange portion 12 in the third positive direction Z1 within the range of the second negative direction Y2, which is closer to the recessed portion 13.

[0036] The third terminal electrode 23 is located on the surface of the second flange portion 14. Specifically, the third terminal electrode 23 is located in the end face of the second flange portion 14 in the third positive direction Z1, within the range of the second positive direction Y1 closer to the recessed portion 15.

[0037] The fourth terminal electrode 24 is located on the surface of the second flange portion 14. Specifically, the fourth terminal electrode 24 is located in the end face of the second flange portion 14 in the third positive direction Z1, within the range of the second negative direction Y2, which is closer to the recessed portion 15. Furthermore, in the accompanying drawings, the first terminal electrode 21, the second terminal electrode 22, the third terminal electrode 23, and the fourth terminal electrode 24 are illustrated with double-dotted lines.

[0038] The first terminal electrode 21 to the fourth terminal electrode 24 are composed of a silver metal layer and copper, nickel, and tin plating layers applied to the surface of the metal layer. In this embodiment, the surface in the coil component 10 where the first terminal electrode 21 to the fourth terminal electrode 24 are disposed is the surface facing the substrate when the coil component 10 is mounted on the substrate.

[0039] (First wire and second wire)

[0040] The coil component 10 includes a first wire 30 and a second wire 40.

[0041] The first wire 30 has a portion that extends spirally on the circumferential surface 11F of the core portion 11, with the central axis CA as the axis of rotation. For example... Figure 3As shown, the first wire 30 is circular in a cross-section orthogonal to its extension direction. Furthermore, the first wire 30 is formed by covering a 30 μm diameter copper wire with a 10 μm insulating film. That is, in a cross-section orthogonal to its extension direction, the diameter of the first wire 30 is 50 μm.

[0042] like Figure 2 As shown, the first end of the first wire 30 is connected to the first terminal electrode 21. A portion of the first wire 30, including the first end, extends from the first terminal electrode 21 toward the ridge closest to the second terminal electrode 22 among the four ridges of the core portion 11.

[0043] When viewed in the first negative direction X2, the first wire 30 is wound clockwise around the core portion 11. A portion of the first wire 30, including the second end opposite to the first end in the extending direction, extends from the edge furthest from the fourth terminal electrode 24 among the four edges of the core portion 11 toward the third terminal electrode 23 near the second flange portion 14 of the core portion 11. The second end of the first wire 30 is connected to the third terminal electrode 23.

[0044] like Figure 1 As shown, the second wire 40 has a portion that extends radially outward from the central axis CA about the central axis CA, with the central axis CA as the axis of rotation. The second wire 40 is a wire with the same cross-sectional shape and size as the first wire 30.

[0045] like Figure 2 As shown, the first end of the second wire 40 is connected to the second terminal electrode 22. A portion of the second wire 40, including the first end, extends toward the ridge furthest from the first terminal electrode 21 among the four ridges of the core portion 11.

[0046] When viewed in the first negative direction X2, the second wire 40 is wound clockwise around the core portion 11. A portion of the second wire 40, including the second end opposite to the first end in the extending direction, extends from the ridge closest to the third terminal electrode 23 among the four ridges of the core portion 11 toward the fourth terminal electrode 24 near the second flange portion 14 of the core portion 11. The second end of the second wire 40 is connected to the fourth terminal electrode 24.

[0047] like Figure 3 As shown, the portion of the first wire 30 that extends spirally on the circumferential surface 11F of the core portion 11 is continuously wound around the central axis CA within a range longer than 360 degrees. Furthermore, when the first wire 30 is wound 360 degrees around the central axis CA, the number of windings is "1". Then, for every 360-degree increase in the winding angle, the number of windings increases by 1.

[0048] Furthermore, in the portion of the first wire 30 that extends spirally on the circumferential surface 11F of the core portion 11, the first turn is defined as the range from the end connected to the first terminal electrode 21 to the point where it is wound 360 degrees around the central axis CA. Specifically, the first turn is defined as the range from the point where the first wire 30 begins to travel from the first end side and begins to contact the core portion 11, to the point where it is wound 360 degrees around the central axis CA along the circumferential surface 11F of the core portion 11. The number of turns of the first wire 30 wound around the core portion 11 is defined as the second turn, the third turn, and so on, as it moves toward the third terminal electrode 23. The last turn on the line of the first wire 30 closest to the end connected to the third terminal electrode 23 is defined as the Mth turn. In this embodiment, the last turn of the first wire 30 refers to the final turn counted from the first turn during the process of winding the first wire 30 onto the core portion 11. That is, in this embodiment, the first wire 30 is wound a total of M turns and half a turn onto the core portion 11. Thus, in the case where there is a portion of the first wire 30 with less than one turn after the Mth turn, the number of turns in that portion is omitted, and the number of turns is represented. That is, the number of times the first wire 30 is wound in this embodiment is M. Furthermore, in this embodiment, "on the path" of the first wire 30 refers to the path along the first wire 30. Additionally, in... Figure 3 In the diagram, dots and the number of turns are added to the first wire 30.

[0049] In the portion of the second wire 40 that extends radially outward from the circumferential surface 11F of the core portion 11, centered on the central axis CA, the first turn is defined as the range from the end of the second wire 40 connected to the second terminal electrode 22 to the point where it is wound 360 degrees around the central axis CA. The number of turns of the second wire 40 wound around the core portion 11 is designated as the second turn, the third turn, and so on, as it moves toward the fourth terminal electrode 24. The last turn of the second wire 40 closest to the end connected to the fourth terminal electrode 24 is designated as the Nth turn. In this embodiment, the last turn of the second wire 40 refers to the final turn made during the process of winding the second wire 40 around the core portion 11, counting from the first turn. That is, in this embodiment, the second wire 40 is wound a total of N turns and half a turn around the core portion 11. Furthermore, the method for counting the number of turns of the second wire 40 is the same as that for the first wire 30. That is, the number of times the second wire 40 is wound is N. Furthermore, in this embodiment, "on the line" of the second wire 40 refers to the path along the second wire 40. Additionally, in Figure 3 The diagram illustrates the second wire 40 being hollow and having additional turns.

[0050] In this embodiment, the number of turns N of the second wire 40 is the same as the number of turns M of the first wire 30. Furthermore, in this embodiment, the number of turns N of the second wire 40 and the number of turns M of the first wire 30 are both 5 or more.

[0051] The first turn of the first wire 30 extends spirally on the circumferential surface 11F of the core portion 11 near the first flange portion 12. The second turn of the first wire 30 extends adjacent to the end of the first turn of the first wire 30 in the first negative direction X2. Similarly, the third to (M-1)th turns of the first wire 30 extend spirally on the circumferential surface 11F of the core portion 11 adjacent to the end of the first turn of the first wire 30 wound in the first negative direction X2, such that the turn with the larger number of turns is located in the first negative direction X2.

[0052] The first turn of the second wire 40 extends radially outward from the boundary between the adjacent first and second turns of the first wire 30 in the direction along the first axis X, centered on the central axis CA. Here, adjacent turns in the direction along the first axis X refer to any turn of the first wire 30 or the second wire 40 and the turn following that arbitrary turn.

[0053] Additionally, the first turn of the second wire 40 extends in contact with the outer surfaces of the first and second turns of the first wire 30, so as to extend along the boundary of the first wire 30 between adjacent turns in the direction along the first axis X.

[0054] The second turn of the second wire 40 extends radially outward from the boundary between the adjacent second and third turns of the first wire 30 in the direction along the first axis X, centered on the central axis CA. Furthermore, the second turn of the second wire 40 extends in contact with the outer surfaces of the second and third turns of the first wire 30 along this boundary. Moreover, the second turn of the second wire 40 extends abutting the end of the first turn of the second wire 40 in the first negative direction X2. Similarly, the third to (N-2)th turns of the second wire 40 abut the end of the second wire 40 wound in the first negative direction X2 of the previous turn, extending spirally in contact with the outer surface of the first wire 30, such that the turn with the larger number of turns is located in the first negative direction X2.

[0055] The (N-1)th turn of the second wire 40 extends adjacent to the end of the (M-1)th turn of the first wire 30 in the first negative direction X2. Then, the Nth turn of the second wire 40 extends adjacent to the end of the (N-1)th turn of the second wire 40 in the first negative direction X2. That is, the (N-1)th turn and the Nth turn of the second wire 40 extend along the circumferential surface 11F of the core portion 11. Therefore, the (N-1)th turn and the Nth turn of the second wire 40 are located radially inward of the first to (N-2)th turns of the second wire 40, centered on the central axis CA.

[0056] Furthermore, the ends of the Mth turn of the first wire 30 and the Nth turn of the second wire 40 extend adjacent to each other in the first negative direction X2. Therefore, the (N-1)th and Nth turns of the second wire 40 are sandwiched between the (M-1)th and Mth turns of the first wire 30.

[0057] (Outer and inner portions)

[0058] The second wire 40 has an outer portion 41 and an inner portion 42. In the second wire 40 described above, the outer portion 41 is the portion from the first turn to the (N-2)th turn, and the inner portion 42 is the portion from the (N-1)th turn to the Nth turn.

[0059] As described above, the outer portion 41, which is formed by the first to the N-2th turns of the second wire 40, extends in a spiral shape toward the radially outer side centered on the central axis CA, closer to the inner portion 42, which is formed by the N-1th and Nth turns of the second wire 40.

[0060] Furthermore, the inner portion 42 is composed of two turns: the (N-1)th turn and the Nth turn of the second wire 40. Therefore, the inner portion 42 extends spirally continuously over a range of 720 degrees, longer than 360 degrees, on the circumferential surface 11F of the core portion 11. In this embodiment, since the number of turns N of the second wire 40 is 5 or more, the number of turns in the inner portion 42 is "2", and the number of turns in the outer portion 41 is "3" or more. Therefore, the number of turns in the outer portion 41 is greater than the number of turns in the inner portion 42.

[0061] Furthermore, the Nth turn of the second wire 40 and the (N-1)th turn of the second wire 40 extend adjacently to each other in the first negative direction X2. Therefore, in the inner portion 42, in a cross-section including the central axis CA, adjacent turns of the second wire 40 in the direction along the first axis X are in contact with each other.

[0062] Furthermore, the (N-1)th and Nth turns of the second wire 40 are located between the (M-1)th and Mth turns of the first wire 30. Therefore, the inner portion 42 is located between adjacent turns of the first wire 30 in the direction along the first axis X. Therefore, when L is set to an integer greater than or equal to 1 and less than or equal to M-1, the inner portion 42 is located between the Lth and (L+1)th turns of the first wire 30. In particular, in this embodiment, L is M-1 of an integer greater than or equal to 1 and less than or equal to M-1.

[0063] (Comparative Test)

[0064] First, the coil component 90 of the comparative example will be described.

[0065] like Figure 4As shown, the coil component 90 of the comparative example differs from the coil component 10 of the above embodiment in that the Mth turn of the first wire 30 and the (N-1)th and Nth turns of the second wire 40 are different. Specifically, in the coil component 90 of the comparative example, the Mth turn of the first wire 30 and the (M-1)th turn of the first wire 30 extend adjacently to each other at their ends in the first negative direction X2. Therefore, there is no second wire 40 between the (M-1)th and Mth turns of the first wire 30.

[0066] In the comparative example coil component 90, the ends of the (N-1)th and (N-2)th turns of the second wire 40 extend adjacent to each other in the first negative direction X2. Additionally, the ends of the Nth turn of the second wire 40 and the Mth turn of the first wire 30 extend adjacent to each other in the first negative direction X2. Therefore, in the portion of the second wire 40 that extends radially outward from the circumferential surface 11F of the core portion 11 centered on the central axis CA, the portion from the first turn to the (N-1)th turn is the outer portion 41. The Nth turn of the second wire 40 is the inner portion 42 located radially inward from the outer portion 41 centered on the central axis CA. However, in the inner portion 42 of the coil component 90, adjacent turns of the second wire 40 do not contact each other, and the inner portion 42 of the coil component 90 is not clamped by adjacent turns of the first wire 30.

[0067] like Figure 5 As shown, Sds21, one of the mode switching characteristics, was compared experimentally between the coil component 10 of the above embodiment and the coil component 90 of the comparative example. Figure 5 In the diagram, the horizontal axis represents frequency, and the vertical axis represents Sds21, which is one of the mode conversion characteristics. Figure 5 In the diagram, solid lines represent the characteristics of the coil component 10 of the above embodiment, and dashed lines represent the characteristics of the coil component 90 of the comparative example. Thus, in the coil component 10 of the above embodiment, compared with the coil component 90 of the comparative example, Sds21 is reduced in the frequency range of 10MHz and below.

[0068] (The role of the implementation method)

[0069] According to the coil component 10 of the above embodiment, the second wire 40 has an inner portion 42. The inner portion 42 extends spirally over a range longer than 360 degrees, specifically within a range of 720 degrees, on the circumferential surface 11F of the core portion 11. Furthermore, the distance between the inner portion 42 and the central axis CA is smaller than that between the outer portion 41 and the inner portion 42. Therefore, the leakage flux of the inner portion 42 is smaller than that of the outer portion 41.

[0070] Furthermore, the inner portion 42 is located between the Lth and L+1th turns of the first wire 30. Specifically, in this embodiment, the inner portion 42 is located between the (M-1)th and Mth turns of the first wire 30. Therefore, the distance between the (M-1)th and Mth turns of the first wire 30 that sandwich the inner portion 42 is equal to the amount by which the inner portion 42 is sandwiched. Therefore, in the first wire 30, compared to the case where the (M-1)th and Mth turns are in contact, the leakage flux is greater.

[0071] (Effects of the implementation method)

[0072] (1) In the coil component 10 according to the above embodiment, the second wire 40 has an inner portion 42. Therefore, as described above, the leakage flux of the second wire 40 is smaller compared to the case where the second wire 40 does not have an inner portion 42. On the other hand, the leakage flux of the first wire 30 is larger compared to the case where the second wire 40 does not have an inner portion 42.

[0073] Therefore, compared to the case where the second wire 40 does not have the inner portion 42, the leakage flux of the second wire 40 is smaller, thereby increasing the inductance value obtained by the second wire 40. On the other hand, compared to the case where the second wire 40 does not have the inner portion 42, the inductance value obtained by the first wire 30 is smaller.

[0074] Therefore, the inductance value obtained from the first wire 30 decreases, while the inductance value obtained from the second wire 40 increases. This reduces the difference between the inductance values ​​obtained from the first wire 30 and the second wire 40. As a result, according to the coil component 10, compared to the case where the second wire 40 does not have the inner portion 42, Sds21, which is one of the mode switching characteristics, can be reduced.

[0075] (2) According to the above embodiment, adjacent turns of the second wire 40 are in contact in the inner portion 42. That is, the inner portion 42 has a contact point in the direction along the central axis CA. Therefore, compared to the case where adjacent turns are not in contact, the generation of leakage flux can be suppressed at the contact point of adjacent turns in the inner portion 42. Therefore, the coil component 10 according to the above embodiment can further suppress the generation of leakage flux between the wires 40 in the inner portion 42 at the contact point.

[0076] (3) In the coil component 10 according to the above embodiment, the inner portion 42 is located between the (M-1)th turn and the Mth turn of the first wire 30. Therefore, during the manufacturing process of the coil component 10, when the core portion 11 winds the first wire 30, only the Mth turn and the (M-1)th turn, which are the last turns, need to be wound separately. Therefore, when the inner portion 42 is arranged between the (M-1)th turn and the Mth turn of the first wire 30, it is not necessary to significantly change the manufacturing apparatus or manufacturing process.

[0077] (4) Assuming that the inner portion 42 does not include the last turn and exists in the middle of the winding of the second wire 40, it is necessary to wind the second wire 40 as the outer portion 41, then wind the second wire 40 as the inner portion 42, and then wind it as the outer portion 41 again. Therefore, when winding the second wire 40, it is sometimes necessary to change the winding method multiple times in the middle of the winding.

[0078] Regarding this, in the coil component 10 according to the above embodiment, the inner portion 42 consists of the (N-1)th and Nth turns of the second wire 40. That is, the inner portion 42 includes the Nth turn, which is the last turn. Therefore, when the core portion 11 winds the second wire 40, it is sufficient to wind the portion including the last turn as the inner portion 42. Therefore, according to the above embodiment, after winding it into the inner portion 42, it is not necessary to change the winding method to wind it into the outer portion 41.

[0079] (5) In the coil component 10 according to the above embodiment, the number of times the first wire 30 is wound is the same as the number of times the second wire 40 is wound. In this case, it is not possible to adjust the inductance value obtained by each wire by the number of windings. In such a structure, in order to reduce the deviation of the inductance value of each wire, it is particularly preferable to provide an inner portion 42 in the second wire 40.

[0080] (6) The number of times the first wire 30 is wound is the same as the number of times the second wire 40 is wound, thereby easily obtaining the symmetry between the coil formed by the first wire 30 and the coil formed by the second wire 40. In addition, it is easy to make the inductance and resistance values ​​of the first wire 30 and the second wire 40 the same.

[0081] (7) In the coil component 10 according to the above embodiment, the number of times the outer portion 41 of the second wire 40 is wound is greater than the number of times the inner portion 42 of the second wire 40 is wound. Since the outer portion 41 has a correspondingly larger number of windings, the inductance value obtained from the outer portion 41 of the second wire 40 is less than the inductance value obtained from the first wire 30, which has the same number of windings as the outer portion 41. In such a structure, in order to reduce the deviation in the inductance values ​​of each wire, it is particularly preferable to provide an inner portion 42 in the second wire 40.

[0082] <Other embodiments of the coil component>

[0083] The above embodiments can be modified as follows. The above embodiments and the following modifications can be combined and implemented within the scope of technical inconsistency.

[0084] • In the above embodiments, the shape of the core portion 11 is not limited to the examples of the above embodiments. For example, it may be cylindrical or a polygonal prism other than a tetrahedral prism.

[0085] • In the above embodiments, the top plate 16 may also be omitted.

[0086] In the above embodiment, the core 10C only needs to include the core portion 11, the first flange portion 12, and the second flange portion 14. For example, the recessed portion 13 may be omitted. In this case, for example, it is sufficient that the first terminal electrode 21 and the second terminal electrode 22 are separated from each other, and the third terminal electrode 23 and the fourth terminal electrode 24 are separated from each other.

[0087] In the above embodiments, the materials and shapes of the first terminal electrode 21 to the fourth terminal electrode 24 are not limited to the examples described in the above embodiments. For example, the plating material of the first terminal electrode 21 to the fourth terminal electrode 24 may also be tin, nickel alloy, etc. In addition, the first terminal electrode 21 to the fourth terminal electrode 24 may not have a plating layer, but instead have a conductive metal layer exposed.

[0088] In the above embodiments, the cross-sectional shape and size of the first wire 30 and the second wire 40 are not limited to the examples of the above embodiments. For example, compared with the above embodiments, the diameter of the copper wire can also be larger, and the thickness of the insulating coating can also be thicker.

[0089] • The number of times the first wire 30 is wound can be different from the number of times the second wire 40 is wound.

[0090] In the above embodiment, the extension range of the inner portion 42 is only required to be a range that is continuously longer than 360 degrees on at least the circumferential surface 11F of the core portion 11. In other words, in the above embodiment, the number of turns of the inner portion 42 is not limited to the example of the above embodiment, as long as it is greater than "1". If the inner portion 42 extends continuously in a range longer than 360 degrees, the inner portion 42 has at least locally adjacent turns.

[0091] In the above embodiment, in the inner portion 42, adjacent turns in the direction along the first axis X may not contact each other in the direction along the central axis CA.

[0092] In the above embodiment, the inner portion 42 is always in contact with the circumferential surface 11F of the core portion 11 and extends in a spiral shape, but it may also be partially separated from the circumferential surface 11F and extend in a spiral shape. For example, when the core portion 11 is viewed from the direction along the central axis CA, the inner portion 42 may be in contact with the circumferential surface 11F near the four corners of the core portion 11, and separated from the circumferential surface 11F between the corners. Even when the inner portion 42 is in intermittent contact with the circumferential surface 11F, it can be said that the inner portion 42 extends on the circumferential surface 11F.

[0093] The number of windings in the inner portion 42 can also be greater than in the example of the above embodiment. Figure 6 In the example shown, the second wire 140 of the coil component 110 has an outer portion 141 and an inner portion 142. The outer portion 141 is the portion of the first to the (N-3)th turns of the second wire 140. Furthermore, in any turn of the outer portion 141, it is separated from the adjacent turn in the extension direction of the central axis CA. Moreover, the inner portion 142 is the portion of the (N-2)th to the Nth turns of the second wire 140. Therefore, the number of times the inner portion 142 is wound is 3. That is, in this modified example, the inner portion 142 extends continuously on the circumferential surface 11F of the core portion 11 within a range longer than 720 degrees. In this case, the inductance value obtained by the second wire 140 can be further greater than the inductance value of the coil component 10.

[0094] • The number of windings in the inner portion 42 can also be greater than or equal to the number of windings in the outer portion 41. This can be adjusted appropriately along with the number of windings in the first wire 30, the number of windings in the second wire 40, or the diameter of the core portion 11 centered on the central axis CA.

[0095] In the above embodiment, the inner portion 42 may not include the Nth turn of the second wire 40. In this case, the inner portion 42 can also be used to increase the inductance value obtained from the second wire 40.

[0096] In the above embodiment, the inner portion 42 may also be located in a region of the first wire 30 that is not between the (M-1)th turn and the Mth turn. For example, it may be located between the (M-2)th turn and the (M-1)th turn of the first wire 30. That is, the inner portion 42 only needs to be located between the Lth turn and the (L+1)th turn of the first wire 30. Even in this case, since the inner portion 42 is sandwiched between the Lth turn and the (L+1)th turn of the first wire 30, the distance between the Lth turn and the (L+1)th turn of the first wire 30 is separated. Therefore, by reducing the inductance value obtained from the first wire 30 and increasing the inductance value obtained from the second wire 40, the difference in inductance values ​​obtained from the two wires can be reduced.

[0097] In the above embodiment, the second wire 40 may also have a portion located inside the outer portion 41, in addition to the inner portion 42. Figure 7 In the example shown, the second wire 240 has an outer portion 241, a first inner portion 242, and a second inner portion 243. The outer portion 241 is the portion from the second turn to the (N-2)th turn of the second wire 240. The first inner portion 242 is the (N-1)th turn and the Nth turn of the second wire 240. The second inner portion 243 is the first turn of the second wire 240. The first inner portion 242 has the same structure as the inner portion 42 of the coil component 10 in the above embodiment. The second inner portion 243 extends on the circumferential surface 11F of the core portion 11 and is located between adjacent turns of the first wire 30, i.e., between the first turn and the second turn of the first wire 30. In this case, the coil component 210 has a second inner portion 243 in addition to the first inner portion 242, thereby enabling the inductance value obtained by the second wire 240 to be further greater than the inductance value of the coil component 10.

[0098] In addition, Figure 7 In the modified example shown, the second inner portion 243 includes the first turn of the second wire 40. Therefore, in terms of setting the second inner portion 243, during the manufacturing process of the coil component 210, only the initial first turn can be wound using a different method than the outer portion 241.

[0099] In addition, Figure 7 In the modified example shown, the second inner portion 243 extends continuously within a range of less than 360 degrees on the circumferential surface 11F of the core portion 11. Therefore, in the second inner portion 243, a smaller amount of leakage flux can be suppressed than that suppressed by the first inner portion 242. As a result, the inductance value obtained from the second wire 40 can be easily adjusted.

[0100] ·exist Figure 7 In the illustrated modification, the second inner portion 243 may not be the first turn of the second wire 40. Figure 8 In the illustrated modification, in the coil component 310, the second wire 340 has an outer portion 341, a first inner portion 342, and a second inner portion 343. The outer portion 341 comprises the first to N-3 turns of the second wire 340. The first inner portion 342 comprises the N-1 and Nth turns of the second wire 340. The second inner portion 343 comprises the N-2th turn. In this case, due to the presence of the second inner portion 343, the M-2nd and M-1st turns of the first wire 30 are also separated along the first axis X. Consequently, the leakage flux of the first wire 30 increases, and therefore the inductance value obtained from the first wire 30 decreases, thereby enabling adjustment of the inductance difference.

[0101] ·exist Figure 7 In the illustrated variation, the second inner portion 243 may also extend continuously over a range longer than 360 degrees on the circumferential surface 11F of the core portion 11. Figure 9 In the illustrated modification, in the coil component 410, the second wire 440 has a first outer portion 441, a second outer portion 442, a first inner portion 443, and a second inner portion 444. The first outer portion 441 is the portion of the first to N-5 turns of the second wire 440. The second outer portion 442 is the N-2th turn of the second wire 440. The first inner portion 443 is the N-1th and Nth turns of the second wire 440. The second inner portion 444 is the N-4th and N-3rd turns of the second wire 440. Multiple inner portions 42 in the coil component 10 of the above embodiments may also be provided in this way. Figure 9 In the modified example shown, compared to the case without the second inner portion 444, the inductance value obtained from the second wire 440 can be further increased.

[0102] ·exist Figure 7 In the illustrated modification, the second inner portion 243 may not be located between the first and second turns of the first wire 30. When K is set to an integer greater than 1 and less than M-1, the second inner portion 243 only needs to be located between the Kth and K+1th turns of the first wire 30. Furthermore, since the second inner portion 243 is provided separately from the first inner portion 242, K is an integer different from L. For example, in Figure 8 In the example of the change shown, K is 1 and L is M-1. Additionally, for example, in... Figure 9 In the example of the change shown, K is M-4 and L is M-1.

[0103] In the above embodiment, the portions of the outer portion 41 and the inner portion 42 located on the surface of the circumferential surface 11F facing the third positive direction Z1 are mainly described. The positional relationship between the outer portion 41 and the inner portion 42 in the direction along the first axis X is satisfied as long as it is satisfied in any section including the central axis CA. Therefore, the same structure may not be used in all surfaces of the circumferential surface 11F. For example, on the surface of the circumferential surface 11F facing the third negative direction Z2, the (M-1)th turn of the first wire 30 may extend radially outward from the central axis CA than the (N-1)th turn of the second wire 40.

Claims

1. A coil component, wherein, have: The core section has a central axis; The first flange portion is connected to the first end of the core portion along the central axis. The second flange portion is connected to the second end of the core portion on the opposite side of the first end; The first terminal electrode and the second terminal electrode are located on the surface of the first flange portion; The third terminal electrode and the fourth terminal electrode are located on the surface of the second flange portion; The first wire has a portion that extends spirally on the circumferential surface of the core portion about the central axis as the axis of rotation, with a first end connected to the first terminal electrode and a second end on the opposite side of the first end connected to the third terminal electrode. as well as The second wire has a portion that extends radially outward from the central axis, about the circumference of the core portion, with the first end connected to the second terminal electrode, and a second end on the opposite side of the first end connected to the fourth terminal electrode. The second wire has an inner portion that extends spirally over a range longer than 360 degrees on the circumferential surface of the core portion, and an outer portion that extends spirally outward from the radially outer side of the inner portion. In the portion of the first wire wound around the core, the first turn closest to the first end of the first wire on the wire's path is designated as the 1st turn, and the last turn closest to the second end of the first wire on the wire's path is designated as the Mth turn. In the portion of the second wire wound around the core, when the first turn closest to the first end of the second wire is designated as the 1st turn, and the last turn closest to the second end of the second wire is designated as the Nth turn, The inner portion includes the Nth turn and is located between the (M-1)th turn and the Mth turn of the first wire. The Mth turn of the first wire is in contact with the Nth turn of the second wire.

2. The coil component according to claim 1, wherein, In the inner portion, in a cross-section including the central axis, adjacent turns of the second wire are in contact with each other in a direction along the central axis.

3. The coil component according to claim 1 or 2, wherein, The number of times the first wire is wound is the same as the number of times the second wire is wound.

4. The coil component according to claim 1 or 2, wherein, The outer portion has a greater number of windings than the inner portion.

5. The coil component according to claim 1 or 2, wherein, The inner portion extends continuously over a range longer than 720 degrees on the circumferential surface of the core portion.

6. The coil component according to claim 1 or 2, wherein, Taking the inner portion as the first inner portion And when K is set to an integer greater than 1 and less than M-2, The second wire has a second inner portion that extends on the circumferential surface of the core portion and is located between the Kth turn and the (K-1)th turn of the first wire.

7. The coil component according to claim 6, wherein, The second inner portion extends within a range of less than 360 degrees on the circumferential surface of the core portion.

8. The coil component according to claim 6, wherein, The second inner portion extends continuously over a range longer than 360 degrees on the circumferential surface of the core portion.

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