Coil components

Abstract

To provide a coil component allowing an orientation thereof to be distinguished.SOLUTION: A coil component 10 includes: a drum core 10C including a winding core portion, a first flange portion 21 and a second flange portion 22; a first outer electrode 31, a second outer electrode 32, a third outer electrode 33, and a fourth outer electrode 34; and a first wire 41 and a second wire 42. The second wire 42 includes a first winding portion 51 and a second winding portion 52. The first winding portion 51 is a portion including plural turns wound around an outer periphery of the first wire 41. The second winding portion 52 is located on a second wire end 42B side relative to the first winding portion 51 and includes less than 1.0 turn continuously wound around the outer periphery of the first wire 41. When a position closest to a second wire end side 42A in the first winding portion 51 is an end point of the first winding portion 51, the first winding portion 51 includes a first traverse portion 61 that runs across the first wire 41 without running in the same layer as the first wire 41 in a section from the end point to a point before one turn.SELECTED DRAWING: Figure 2

Description

Technical Field

[0001] The present disclosure relates to coil components.

Background Art

[0002] The coil component described in Patent Document 1 includes a core, four external electrodes, a first wire, and a second wire. The core includes a winding core portion, a first flange portion, and a second flange portion. The winding core portion is quadrangular prism-shaped. The first flange portion is connected to the first end of the winding core portion. The second flange portion is connected to the second end of the winding core portion. Two of the four external electrodes are located on the surface of the first flange portion. The remaining two external electrodes are located on the surface of the second flange portion.

[0003] The first wire is wound around the winding core portion. The first end of the first wire is connected to the external electrode on the first flange portion. The second end of the first wire is connected to the external electrode on the second flange portion side. The second wire is wound around the winding core portion. The first end of the second wire is connected to the external electrode on the first flange portion. The second end of the second wire is connected to the external electrode on the second flange portion. The second wire is wound in the same direction as the first wire.

Prior Art Documents

Patent Documents

[0004]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0005] In coil components like those described in Patent Document 1, the electrical and magnetic properties may change depending on the direction of the current flowing through each wire. Therefore, in order to obtain the expected properties of a coil component, it is necessary to mount the coil component on the substrate in a predetermined orientation. For example, it is conceivable to make the orientation of the coil component identifiable by attaching an optically observable mark to the core of the coil component. However, in this case, it would be necessary to add a manufacturing process solely for the purpose of attaching such a mark, thus unavoidable complexity in the manufacturing process. [Means for solving the problem]

[0006] To solve the above problems, the present invention provides a drum core having a columnar winding core, a first flange connected to a first end in a direction along the central axis of the winding core, and a second flange connected to a second end of the winding core opposite to the first end; a first external electrode and a second external electrode located on the surface of the first flange; a third external electrode and a fourth external electrode located on the surface of the second flange; a first wire wound around the winding core, with its first end connected to the first external electrode and its second end connected to the third external electrode; and a second wire wound around the winding core in the same direction as the first wire, with its first end connected to the second external electrode and its second end connected to the fourth external electrode, wherein the number of turns of the first wire increases by one each time it makes a full rotation around the central axis from the first end toward the second end, and the first end of the second wire The number of turns increases by 1 for each revolution around the central axis from the first wire towards the second wire end, and the second wire comprises a first winding portion wound around the first wire on the outer circumference over a plurality of turns, and a second winding portion located closer to the second wire end than the first winding portion, with at least a portion wound around the outer circumference of the winding core, and the range continuously wound around the outer circumference of the first wire being less than 1.0 turn, and when the second wire is traced from the first wire end to the second wire end in the first winding portion, the position of the first winding portion closest to the second wire end is defined as the end point of the first winding portion, and the first winding portion is a coil component having a first crossing point that straddles the first wire without reaching the same layer of the first wire in the section from the end point to the point one turn before the end point. [Effects of the Invention]

[0007] The orientation of the coil component can be determined without marking the core. [Brief explanation of the drawing]

[0008] [Figure 1] Figure 1 is a perspective view of a coil component. [Figure 2] Figure 2 is a plan view of the coil component. [Figure 3]Figure 3 illustrates the winding pattern of the wire when viewing the coil component facing the third negative direction. [Figure 4] Figure 4 illustrates the winding pattern of the wire when viewing the coil component facing the second positive direction. [Figure 5] Figure 5 illustrates the winding pattern of the wire when viewing the modified coil component from the second positive direction. [Modes for carrying out the invention]

[0009] <About the overall structure> As shown in Figure 1, the coil component 10 comprises a drum core 10C and a top plate 10F.

[0010] The drum core 10C has a winding core portion 11, a first flange portion 21, and a second flange portion 22. The core portion 11 is rectangular in shape. The cross-section perpendicular to the central axis 11C of the core portion 11 is rectangular. Here, "rectangular" means that it has four sides and is rectangular overall, and includes shapes where the corners of the rectangle are chamfered. In this embodiment, the material of the core portion 11 is Ni-Zn ferrite. The material of the core portion 11 can also be alumina, Ni-Zn ferrite, synthetic resin, or mixtures thereof.

[0011] Here, a specific axis parallel to the central axis 11C of the winding core 11 is defined as the first axis X. An axis perpendicular to the first axis X is defined as the second axis Y. In this embodiment, the second axis Y is parallel to two of the four sides of the winding core 11 when viewed in the direction along the first axis X. An axis perpendicular to both the first axis X and the second axis Y is defined as the third axis Z. In this embodiment, the third axis Z is parallel to the remaining two of the four sides of the winding core 11 when viewed in the direction along the first axis X. One of the directions along the first axis X is defined as the first positive direction X1, and the direction opposite to the first positive direction X1 is defined as the first negative direction X2. Similarly, one of the directions along the second axis Y is defined as the second positive direction Y1, and the direction opposite to the second positive direction Y1 is defined as the second negative direction Y2. Furthermore, one of the directions along the third axis Z is designated as the third positive direction Z1, and the direction opposite to the third positive direction Z1 is designated as the third negative direction Z2. In this embodiment, a specific direction perpendicular to the central axis 11C coincides with the third positive direction Z1.

[0012] As shown in Figure 1, the first flange portion 21 is connected to the first end, which is the end of the first positive direction X1 of the winding core portion 11. The first flange portion 21 is integrally molded with the winding core portion 11. Therefore, the material of the first flange portion 21 is the same Ni-Zn ferrite as the winding core portion 11.

[0013] The first flange portion 21 protrudes outward from the winding core portion 11 in the direction along the second axis Y and the direction along the third axis Z. Furthermore, the central portion 21A of the first flange portion 21 in the direction along the second axis Y protrudes in the third positive direction Z1 from both ends in the direction along the second axis Y. In other words, the ends of the first flange portion 21 in the second positive direction Y1 and the ends in the second negative direction Y2 are recessed in the third negative direction Z2 relative to the central portion 21A in the direction along the second axis Y.

[0014] The second flange portion 22 is connected to the second end, which is the end of the winding core portion 11 on the first negative direction X2 side. The second flange portion 22 is integrally molded with the winding core portion 11. Therefore, the material of the second flange portion 22 is the same Ni-Zn ferrite as the winding core portion 11.

[0015] The second flange portion 22 protrudes outward with respect to the core portion 11 in the direction along the second axis Y and the direction along the third axis Z. Further, among the second flange portions 22, the central portion 22A in the direction along the second axis Y protrudes in the third positive direction Z1 with respect to both ends in the direction along the second axis Y. In other words, the end portions in the second positive direction Y1 and the end portions in the second negative direction Y2 of the second flange portion 22 are recessed in the third negative direction Z2 with respect to the central portion 22A in the direction along the second axis Y.

[0016] The top plate 10F is in the shape of a rectangular plate. The dimension of the top plate 10F in the third axis Z is smaller than the dimensions in the direction along the first axis X and the direction along the second axis Y. The long side of the top plate 10F is parallel to the first axis X. The short side of the top plate 10F is parallel to the second axis Y. The top plate 10F is located on the third negative direction Z2 side with respect to the drum core 10C. The top plate 10F is connected to both the surface facing the third negative direction Z2 in the first flange portion 21 and the surface facing the third negative direction Z2 in the second flange portion 22. That is, the top plate 10F is spanned between the first flange portion 21 and the second flange portion 22. The material of the top plate 10F is the same Ni-Zn ferrite as that of the drum core 10C. In addition, in FIGS. 3 to 5, the illustration of the top plate 10F is omitted.

[0017] The coil component 10 includes four external electrodes 30. The four external electrodes 30 are the first external electrode 31, the second external electrode 32, the third external electrode 33, and the fourth external electrode 34. The first external electrode 31 is attached to the first flange portion 21. The first external electrode 31 is located on the surface on the second positive direction Y1 side with respect to the center in the direction along the second axis Y in the first flange portion 21. Further, most of the first external electrode 31 is located on the third positive direction Z1 side with respect to the core portion 11.

[0018] The first external electrode 31 has an adhesive portion BP, a connecting portion CP, and a joining portion JP. Note that the adhesive portion BP, the connecting portion CP, and the joining portion JP are integrally molded. That is, there is no clear boundary between these members inside the first external electrode 31.

[0019] The connecting part BP is substantially plate-shaped. When the connecting part BP is viewed from the direction along the second axis Y, the connecting part BP is substantially L-shaped. That is, the connecting part BP has a plane orthogonal to the first axis X and a plane orthogonal to the third axis Z. A part of the plane of the connecting part BP orthogonal to the first axis X is adhered to the surface of the first flange part 21 on the first positive direction X1 side.

[0020] The connecting portion CP is substantially plate-shaped. The connecting portion CP is connected to the end face on the second positive direction Y1 side of the connecting portion BP. The connecting portion CP extends toward the second positive direction Y1 as it goes toward the third negative direction Z2. And when viewed from the direction along the first axis X, the connecting portion BP is substantially L-shaped. Therefore, the connecting portion CP has a plane orthogonal to the second axis Y and a plane orthogonal to the third axis Z.

[0021] The joining part JP is substantially plate-shaped. The joining part JP is connected to the end face on the second positive direction Y1 side of the connecting part CP. The joining part JP is located on the surface of the first flange part 21 facing the third positive direction Z1. That is, the joining part JP is located on the surface of the first flange part 21 on the third positive direction Z1 side with respect to the central axis 11C. The wire end described later is connected to the surface of the joining part JP facing the third positive direction Z1. Thus, if the joining part JP to which the wire end is connected is located on the surface of the first flange part 21 on the third positive direction Z1 side with respect to the central axis 11C, it can be said that the first external electrode 31 is located on the surface of the first flange part 21 on the third positive direction Z1 side with respect to the central axis 11C.

[0022] The second external electrode 32 is attached to the first flange part 21. The second external electrode 32 is located on the surface on the second negative direction Y2 side with respect to the center in the direction along the second axis Y in the first flange part 21. Most of the second external electrode 32 is located on the third positive direction Z1 side with respect to the core part 11. The second external electrode 32 has a symmetrical shape with respect to the first external electrode 31. Specifically, the second external electrode 32 and the first external electrode 31 are symmetric with respect to a virtual plane passing through the central axis 11C and orthogonal to the second axis Y. Therefore, the second external electrode 32 is located on the surface of the first flange part 21 on the third positive direction Z1 side with respect to the central axis 11C.

[0023] The third external electrode 33 is attached to the second flange portion 22. The third external electrode 33 is located on the surface of the second flange portion 22 on the second positive direction Y1 side with respect to the center in the direction along the second axis Y. Most of the third external electrode 33 is located on the third positive direction Z1 side with respect to the winding core portion 11. The third external electrode 33 is symmetrical with respect to the first external electrode 31. Specifically, the third external electrode 33 and the first external electrode 31 are symmetrical with respect to a virtual plane perpendicular to the central axis 11C and passing through the center C of the winding core portion 11. Therefore, the third external electrode 33 is located on the surface of the second flange portion 22 on the third positive direction Z1 side with respect to the central axis 11C.

[0024] The fourth external electrode 34 is attached to the second flange portion 22. The fourth external electrode 34 is located on the surface of the second flange portion 22 on the second negative direction Y2 side with respect to the center in the direction along the second axis Y. Most of the fourth external electrode 34 is located on the third positive direction Z1 side with respect to the winding core portion 11. The fourth external electrode 34 is symmetrical with respect to the third external electrode 33. Specifically, the fourth external electrode 34 and the third external electrode 33 are symmetrical with respect to a virtual plane passing through the central axis 11C and perpendicular to the second axis Y. Therefore, the fourth external electrode 34 is located on the surface of the second flange portion 22 on the third positive direction Z1 side with respect to the central axis 11C.

[0025] In this embodiment, the maximum dimension of the coil component 10 in the direction along the first axis X is 3.2 mm. The maximum dimension of the coil component 10 in the direction along the second axis Y is 2.5 mm. The maximum dimension of the coil component 10 in the direction along the third axis Z is 2.3 mm.

[0026] <Regarding the first and second wires> As shown in Figure 1, the coil component 10 comprises a first wire 41 and a second wire 42. The first wire 41 and the second wire 42 are wound around the winding core 11. Although not shown in the figure, the first wire 41 has a conductor and an insulating coating. The insulating coating covers the outer surface of the conductor. The first wire 41 has a substantially circular shape in cross-section perpendicular to the direction in which the first wire 41 extends.

[0027] The second wire 42 has the same configuration as the first wire 41. That is, the second wire 42 has a conductor and an insulating coating. Note that in Figures 3 to 5, the first wire 41 is colored with dots.

[0028] As shown in Figure 2, the first wire end 41A of the first wire 41 is connected to the first external electrode 31. The second wire end 41B of the first wire 41 is connected to the third external electrode 33. The first wire end 41A and the second wire end 41B are connected to the corresponding joint JP of the external electrode 30 by thermocompression bonding. Thermocompression bonding is a method of fixing the wire to the external electrode 30 by sandwiching the wire between the external electrode 30 and a heated jig and melting the wire.

[0029] Here, when tracing the first wire 41 from the first wire end 41A to the second wire end 41B, the point where it first contacts the outer surface of the winding core 11 is defined as the 1.0 turn point of the first wire 41. In this embodiment, the 1.0 turn point of the first wire 41 is located on the ridge of the winding core 11 on the second negative direction Y2 side and the third positive direction Z1 side.

[0030] As shown in Figures 3 and 4, the number of turns of the first wire 41 increases by one for each revolution around the central axis 11C, from the first end 41A to the second end 41B. The first wire 41 is wound around the core 11 such that, when viewed in the first negative direction X2, it progresses clockwise as the number of turns increases. Therefore, for example, when viewed in the first negative direction X2, the point 36 degrees from the point of 1.0 turn of the first wire 41 around the central axis 11C is the point of 1.1 turn of the first wire 41. In Figure 3, the number of turns of each wire at the ridge position on the third positive direction Z1 side of the core 11 is schematically illustrated. In Figure 4, the number of turns of each wire located on the central axis 11C of the core 11 is schematically illustrated when viewed in the second positive direction Y1.

[0031] As shown in Figure 3, the first wire 41 is wound directly around the core 11 without passing through the second wire 42 around its entire circumference. Here, "directly wound" includes not only the state in which the wire is in contact with the outer surface of the core 11, but also the state in which the wire is wound around the core 11 without any other wires in between, even when the wire is floating.

[0032] Furthermore, the first turn of the first wire 41 refers to the section from the point of the 1.0 turn of the first wire 41 to just before the point of the 2.0 turn. Also, the final turn of the first wire 41 is the turn that includes the point where the first wire 41, when traced from the first wire end 41A to the second wire end 41B, finally makes contact with the outer surface of the winding core 11. In this embodiment, the final turn of the first wire 41 is 21 turns.

[0033] As shown in Figure 2, the first end 42A of the second wire 42 is connected to the second external electrode 32. The second end 42B of the second wire 42 is connected to the fourth external electrode 34. The first end 42A and the second end 42B are connected to the corresponding joint JP of the external electrode 30 by thermocompression bonding.

[0034] Here, when tracing the second wire 42 from the first end 42A to the second end 42B, the point where the angular position around the central axis 11C first coincides with the angular position of the 1.0 turn of the first wire 41 is defined as the 1.0 turn of the second wire 42. That is, in this embodiment, the 1.0 turn of the second wire 42 is located on a straight line connecting the ridge of the winding core 11 on the second negative direction Y2 and the third positive direction Z1 side with the central axis 11C when viewed in the direction along the first axis X. In this embodiment, when tracing the second wire 42 from the first end 42A to the second end 42B, the 1.0 turn of the second wire 42 is in contact with the outer surface of the first wire 41 that is opposite to the surface facing the central axis 11C. The 1.0 turn of the second wire 42 may also be in contact with the outer surface of the winding core 11.

[0035] As shown in Figures 3 and 4, the number of turns of the second wire 42 increases by one for each revolution around the central axis 11C, from the first end 42A to the second end 42B. The second wire 42 is wound around the core 11 such that, when viewed in the first negative direction X2, it progresses clockwise as the number of turns increases. In other words, the second wire 42 is wound in the same direction as the first wire 41. A portion of the second wire 42 is wound around the core 11 from the outside relative to the first wire 41. In other words, a portion of the second wire 42 is in contact with the outer surface of the first wire 41 that is opposite to the surface facing the central axis 11C.

[0036] Furthermore, the final turn of the second wire 42 is the turn that includes the point where the second wire 42 finally contacts the outer surface of the winding core 11 when traced from the first wire end 42A to the second wire end 42B. In this embodiment, the final turn of the second wire 42 is 21 turns. Note that in Figures 3 and 4, the portion of each wire located closer to the first wire end than 1.0 turn is shown as 0 turns.

[0037] <Regarding the winding of the first and second wires> As shown in Figure 2, the second wire 42 comprises a first winding portion 51 and a second winding portion 52.

[0038] As shown in Figure 3, the first winding portion 51 is the part that is wound around the outer circumference of the first wire 41 over multiple turns. In this embodiment, the first winding portion 51 is the part of the second wire 42 from the 1.0 turn to partway through the 17th turn. That is, the first winding portion 51 is the part of the second wire 42 from the point where it rides up on the outer surface of the first wire 41 to the point just before it is wound directly onto the winding core 11.

[0039] As shown in Figures 3 and 4, the second wire 42 is wound directly around the outer circumference of the first wire 41 from the first to the eighth turn. Then, midway through the ninth turn of the second wire 42, the second wire 42 is wound directly around the outer circumference of the portion of the second wire 42 prior to the eighth turn. That is, midway through the ninth turn of the second wire 42, it rides up onto the outer circumference of the second layer portion of the second wire 42. Specifically, the ninth turn of the second wire 42 rides up onto the outer circumference of the second layer portion of the second wire 42 on the second positive direction Y1 side of the winding core 11. Then, from the middle of the ninth turn of the second wire 42, it is wound between the sixth and seventh turns of the second wire 42. In this way, the first winding section 51 includes a portion TL on the outer circumference side of the first wire 41 where the second wire 42 is wound over two or more layers.

[0040] As shown in Figure 4, the 9th turn of the second wire 42 crosses the first wire 41 on the surface of the winding core 11 on the second positive direction Y1 side. Here, "crossing" means that one wire straddles the other wire without reaching the same layer as the other wire. Because such crossing points exist, the second wire 42 has points within one turn where it contacts the first wire 41 at turn X, turn X+1, and turn X+2 (where X is a positive integer). When tracing the second wire 42 from the first wire end 42A to the second wire end 42B, at the crossing points, the second wire 42 straddles the first wire 41 from the first negative direction X2 side to the first positive direction X1 side. Here, when an upper layer wire straddles a lower layer wire, it is expressed as "the upper layer wire straddles the lower layer wire." Therefore, for example, "the second wire 42 straddles the first wire 41" means that the upper second wire 42 straddles the first wire 41 which is wound in a lower layer. In this embodiment, the portion of the 9th turn of the second wire 42 within 0.5 turns is located between the 9th and 10th turns of the first wire 41. On the other hand, the portion of the 9th turn of the second wire 42 beyond 0.5 turns is located between the 6th and 7th turns of the second wire 42. The 9th turn of the upper second wire 42 has a portion that indirectly contacts the 7th, 8th, and 9th turns of the first wire 41, respectively, via the second layer of the second wire 42. Here, the groove formed between two adjacent turns of wire is called the wire valley. In this case, the 9th turn of the second wire 42 spans two valleys of the first wire 41 in the direction along the central axis 11C.

[0041] Similarly, the 10th turn of the second wire 42 is directly wound around the outer circumference of the second layer of the second wire 42. Then, midway through the 11th turn of the second wire 42, the second wire 42 moves from the outer circumference of the second layer of the second wire 42 to the outer circumference of the first wire 41. Specifically, the 11th turn of the second wire 42 moves to the outer circumference of the first wire 41 on the second positive direction Y1 side of the winding core 11. Then, from the 12th to the 16th turn of the second wire 42, it is directly wound around the outer circumference of the first wire 41 over its entire circumference.

[0042] As shown in Figure 3, the 16th turn of the second wire 42 has a cross-section with respect to the first wire 41. Specifically, the 16th turn of the second wire 42 has contact points with the 16th, 17th, and 18th turns of the first wire 41, respectively. Specifically, these cross-sections are located on the outer circumferential surface of the winding core 11 on the third positive direction Z1 side with respect to the central axis 11C. That is, the cross-sections are located at a point where the 16th turn has been wound 0.5 turns or more.

[0043] The second wire 42 moves from the outer surface of the first wire 41 to the outer surface of the core 11 during the 17th turn. Specifically, as shown in Figure 4, during the 17th turn of the second wire 42, it moves from the outer surface of the first wire 41 to the outer surface of the core 11 on the third negative direction Z2 side of the core 11. In other words, the second wire 42 moves to the outer surface of the core 11 within a range of 17.0 turns to 17.5 turns.

[0044] In this second wire 42, the point just before it is directly wound around the outer surface of the core 11 is the position in the first winding section 51 closest to the second end 42B when the second wire 42 is traced from the first end 42A to the second end 42B. In other words, the point located on the third negative direction Z2 side at the 17th turn is the end point EP of the first winding section 51.

[0045] In this embodiment, the crossing point of the second wire 42 at the 16th turn is a first crossing point 61 that straddles the first wire 41 without reaching the same layer as the first wire 41 in the section from the end point EP to the turn before that point. In other words, the first winding section 51 has a first crossing point 61.

[0046] As shown in Figure 2, the first crossing point 61 is located on the third positive direction Z1 side with respect to the central axis 11C. Specifically, the first crossing point 61 is located on the outer circumferential surface of the winding core 11 on the third positive direction Z1 side with respect to the central axis 11C. That is, when the central axis 11C is used as the reference, the first crossing point 61 is located on the same side as the joint JP of each external electrode 30. Furthermore, when the second wire 42 is traced from the first wire end 42A to the second wire end 42B, at the first crossing point 61, in the direction along the central axis 11C, the second wire 42 crosses the first wire 41 from the first positive direction X1 side to the first negative direction X2 side.

[0047] As shown in Figure 2, when viewed from the third negative direction Z2, the first winding portion 51 is located on the first flange portion 21 side relative to the center C of the winding core portion 11 in the direction along the central axis 11C. In other words, the first winding portion 51 is located towards the first positive direction X1 side of the winding core portion 11.

[0048] As shown in Figure 3, the second winding section 52 is located on the second wire end 42B side of the second wire 42 relative to the first winding section 51. The second winding section 52 is a winding section of the second wire 42 in which at least a portion is wound around the outer circumference of the winding core 11, and the range in which the second wire 42 is continuously wound around the outer circumference of the first wire 41 is less than 1.0 turn. Specifically, the second winding section 52 extends from the middle of the 17th turn of the second wire 42 to the final turn of the second wire 42. In other words, the second winding section 52 includes the final turn of the second wire 42.

[0049] As shown in Figures 3 and 4, the 18th and 19th turns of the second wire 42 are directly wound around the outer surface of the core 11 over its entire circumference. The 18th turn of the second wire 42 is located on the first negative direction X2 side relative to the 18th turn of the first wire 41. The outer surface of the 18th turn of the second wire 42 on the first positive direction X1 side is in contact with the outer surface of the 18th turn of the first wire 41 on the first negative direction X2 side. On the other hand, the 17th turn of the second wire 42 is separated from the 18th turn of the first wire 41 in the direction along the central axis 11C.

[0050] Furthermore, the 19th turn of the first wire 41 is located on the first negative direction X2 side relative to the 18th turn of the second wire 42. The 19th turn of the second wire 42 is located on the first negative direction X2 side relative to the 19th turn of the first wire 41. The outer surface of the 19th turn of the second wire 42 on the first positive direction X1 side is in contact with the outer surface of the 19th turn of the first wire 41 on the first negative direction X2 side. On the other hand, the 18th turn of the second wire 42 is located away from the 19th turn of the first wire 41 in the direction along the central axis 11C. That is, the second winding portion 52 has a portion PA that is spaced away from adjacent wires on at least one side in the direction along the central axis 11C. Also, the outer circumferential surface of the winding core portion 11 is exposed from the portion PA that is spaced away from adjacent wires in the direction along the central axis 11C.

[0051] The second winding section 52 has a first intersection point 62 that crosses the first wire 41. Specifically, the turn immediately preceding the final turn of the second wire 42 and the turn immediately preceding the final turn of the first wire 41 have a first intersection point 62 where they cross each other. That is, in this embodiment, the 20th turn of the second wire 42 has a first intersection point 62. Here, "crossing" means that when one wire is traced from the first wire end to the second wire end, one wire that is on the same layer as the other wire temporarily rides up on the outer circumference of the other wire and then returns to the same layer as the other wire. Also, in this embodiment, as shown in Figure 2, when viewed in a direction perpendicular to the central axis 11C of the winding core section 11, the point where the center line of the second wire 42 crosses the center line of the first wire 41 is defined as the "intersection point". It should be noted that although it was explained here that "the center line of the second wire 42 intersects the center line of the first wire 41," this is synonymous with "the center line of the first wire 41 intersects the center line of the second wire 42."

[0052] As shown in Figure 2, in this embodiment, the first intersection point 62 is located on the third positive direction Z1 side with respect to the central axis 11C. Specifically, the first intersection point 62 is located on the outer circumferential surface of the winding core 11 on the third positive direction Z1 side with respect to the central axis 11C. That is, when the central axis 11C is used as the reference, the first intersection point 62 is located on the same side as the joint portion JP of each external electrode 30. Furthermore, when the second wire 42 is traced from the first wire end 42A to the second wire end 42B, at the first intersection point 62, in the direction along the central axis 11C, the second wire 42 crosses over the first wire 41 from the first negative direction X2 side to the first positive direction X1 side. That is, suppose the second wire 42 is traced from the first wire end 42A to the second wire end 42B. At this time, the direction in which the second wire 42 crosses the first wire 41 along the central axis 11C at the first crossing point 61 is opposite to the direction in which the second wire 42 crosses the first wire 41 along the central axis 11C at the first intersection point 62.

[0053] In this embodiment, the second winding section 52 has no intersections other than the first intersection 62. The portion of the second winding section 52 other than the first intersection 62 is directly wound around the outer surface of the winding core 11. In other words, the second winding section 52 rides up over the first wire 41 only in the vicinity of the first intersection 62. Therefore, the portion of the second winding section 52 that is continuously wound around the outer surface of the first wire 41 is less than 1.0 turn.

[0054] As shown in Figure 2, when the second wire 42 is traced from the first wire end 42A to the second wire end 42B, the point TP at which it last contacts the outer surface of the winding core 11 is the point at the 21st turn where it contacts the ridge of the winding core 11 on the third positive direction Z1 side and the second positive direction Y1 side. When the winding core 11 is divided into three equal regions along the central axis 11C, this point TP is located in the region AP closest to the second flange 22 among the three regions.

[0055] Incidentally, the 1.0 turn of the first wire 41 is located on the first positive direction X1 side relative to the 1.0 turn of the second wire 42. Therefore, as shown in Figure 4, when viewing the coil component 10 facing the second positive direction Y1, the second wire 42 crosses the first wire 41 near the 1.0 turn of the second wire 42. At this crossing point near the 1.0 turn, when tracing the second wire 42 from the first wire end 42A to the second wire end 42B, the second wire 42 crosses the first wire 41 from the first positive direction X1 side to the first negative direction X2 side.

[0056] Thus, the second wire 42 crosses the first wire 41 at four points: the intersection near the 1.0 turn, the crossing point at the 9th turn of the second wire 42, the first crossing point 61, and the first intersection point 62. In two of these four points, when tracing the second wire 42 from the first wire end 42A to the second wire end 42B, the second wire 42 crosses the first wire 41 from the first positive direction X1 to the first negative direction X2. In the remaining two points, the second wire 42 crosses the first wire 41 in the opposite direction.

[0057] <Regarding mode conversion characteristics> The coil component 10 of this embodiment, the coil component of Comparative Example 1, and the coil component of Comparative Example 2 were used, and Ssd12 was measured as an index of mode conversion characteristics. The various dimensions of the coil component of Comparative Example 1 and the coil component of Comparative Example 2 are the same as those of the coil component 10 of this embodiment. Also, the material of the drum core and the material of the top plate in the coil component of Comparative Example 1 and the coil component of Comparative Example 2 are the same as those of the coil component 10 of this embodiment. Furthermore, the number of turns of each wire in the coil component of Comparative Example 1 and the coil component of Comparative Example 2 is the same as that of the coil component 10 of this embodiment, which is 21 turns. On the other hand, the intersection point in the coil component of Comparative Example 1, which is located closest to the second wire end, is located on the outer circumferential surface of the winding core 11 facing the second negative direction Y2, rather than on the same side as the joint JP of each external electrode 30 when the central axis 11C is used as the reference. Specifically, the intersection point in the coil component of Comparative Example 1 is the 21st turn of the first wire and the second wire. Furthermore, in the coil component of Comparative Example 2, the intersection point located closest to the second wire end is not on the same side as the joint JP of each external electrode 30 when the central axis 11C is used as a reference, but rather on the outer surface of the winding core 11 facing the third negative direction Z2. Specifically, the intersection point in the coil component of Comparative Example 2 is the 21st turn of the first and second wires. Twenty of each coil component were created. That is, the sample size for each coil component was set to 20.

[0058] In the measurement, the coil component 10 of this embodiment, the coil component of Comparative Example 1, and the coil component of Comparative Example 2 were each mounted on an Open Alliance-compliant 3-port board. After SOLT calibration was performed on each coil component, the SSD 12 of each coil component was measured. The average of the measurement results obtained from each coil component, i.e., the 20 measurement results, was used as the representative value of the measurement results.

[0059] In the coil component 10 of this embodiment, when the measurement frequency was 500 kHz, the Ssd12 was -77.5 dB. In the coil component of Comparative Example 1, when the measurement frequency was 500 kHz, the Ssd12 was -75.0 dB. In the coil component of Comparative Example 2, when the measurement frequency was 500 kHz, the Ssd12 was -76.2 dB. In other words, it was found that the value of Ssd12 can be suppressed when the first cross-section 61 is on the third positive direction Z1 side. In other words, it was found that the value of Ssd12 can be suppressed more effectively when the first cross-section 61 and the junction JP of the external electrode 30 are located on the same side than when the first cross-section 61 and the junction JP of the external electrode 30 are located on different sides.

[0060] <Effects of this embodiment> (1) According to the above embodiment, in the area where the first winding portion 51 of the second wire 42 is present, the first wire 41 and the second wire 42 have a structure of two or more layers. On the other hand, the second winding portion 52 of the second wire 42 is not wound on the outer circumference of the first wire 41 and has a single-layer structure. Thus, the layer structure of the wires is asymmetrical on the winding core portion 11 between the first flange portion 21 side and the second flange portion 22 side. Because of this asymmetrical structure, the orientation of the coil component 10 can be easily determined by observing its appearance.

[0061] Furthermore, in the above configuration, the first winding section 51 has a first crossing point 61. In the turns before and after the first crossing point 61, the positional relationship between the first wire 41 and the second wire 42 in the direction along the central axis 11C is reversed. By providing such an intersection point in the first winding section 51, the number of intersection points that need to be provided in the second winding section 52 to eliminate the twisted structure of the two wires can be reduced by one. And if the number of intersection points with respect to the first wire 41 in the second winding section 52 can be reduced, the number of places in the second winding section 52 where the second wire 42 rides on the first wire 41 can be reduced. In other words, the area on the winding core 11 where only the second wire 42 is continuously wound in a single layer structure can be increased. Therefore, it becomes easier to distinguish whether each wire has a structure of two or more layers or a single layer structure.

[0062] (2) In the above embodiment, the first winding portion 51 is located on the side of the first flange portion 21 relative to the center C of the winding core portion 11 in the direction along the central axis 11C. In this way, by clearly separating the area where the first winding portion 51 is located from the area where the second winding portion 52 is located with the center C of the winding core portion 11 as the boundary, it is easy for inspection equipment and the like to determine the orientation of the coil component 10.

[0063] (3) In the above embodiment, the first winding portion 51 includes a portion TL on the outer circumference side of the first wire 41 in which the second wire 42 is wound over two or more layers. That is, the coil component 10 includes a portion in which the coil is wound over a total of three layers. This makes it possible to make the appearance of the area where the first winding portion 51 is located more distinct from the appearance of the area where the second winding portion 52 is located.

[0064] (4) In the above embodiment, the second winding portion 52 includes the final turn of the second wire 42. The turn immediately preceding the final turn of the second wire 42 and the turn immediately preceding the final turn of the first wire 41 intersect each other at a first intersection point 62. Thus, the first intersection point 62, in the direction along the central axis 11C, encompasses the portion of the second wire 42 that is drawn toward the fourth external electrode 34 and the final turn, before reaching the second wire end 42B. In other words, the first intersection point 62 is located away from the second wire end 42B. Therefore, during the manufacturing process, the total amount of heat concentrated at the first intersection point 62 when the second wire end 42B of the second wire 42 is heat-compressed can be reduced.

[0065] (5) In the above embodiment, the first intersection point 62 is located on the third positive direction Z1 side with respect to the central axis 11C. In other words, the first intersection point 62 is located on the same side as the junction JP of the external electrode 30. With this configuration, as shown in the measurement results of Ssd12, the asymmetry of electrical characteristics such as inductance and capacitance is reduced, and as shown in the measurement results of Ssd12, the mode conversion characteristics are improved. That is, with this configuration, Ssd12 is improved compared to a coil component in which the first intersection point 62 is located at a position other than the third positive direction Z1 side of the winding core 11.

[0066] (6) In the above embodiment, the direction in which the second wire 42 crosses the first wire 41 along the central axis 11C at the first crossing point 61 is opposite to the direction in which the second wire 42 crosses the first wire 41 along the central axis 11C at the first intersection point 62. At the point where the wires cross, the first wire 41 is pressed against the second wire 42 and wound around it. Therefore, an external force acts on the first wire 41 in the direction in which the second wire 42 crosses. Because the direction of crossing is different at the first crossing point 61 and the first intersection point 62, the external forces acting on the first wire 41 cancel each other out. As a result, with the above configuration, the position of the first wire 41 is less likely to shift, and the winding of the second wire 42 is stable.

[0067] (7) In the above embodiment, the second winding portion 52 has a portion PA that is spaced apart from adjacent wires in the direction along the central axis 11C. As described above, the core portion 11 is exposed from the portion PA that is spaced apart from adjacent wires. Since the material of each wire and the material of the core portion 11 are different, the optical properties of the wire and the core portion 11 are different. Therefore, the orientation of the coil component 10 can also be determined by optically observing the core portion 11 in the section where the second winding portion 52 is located.

[0068] (8) In the above embodiment, when the second wire 42 is traced from the first wire end 42A to the second wire end 42B, the point TP at which it finally contacts the outer surface of the winding core 11 is located in the region AP closest to the second flange 22 among the three regions described above. That is, the final turn of the second wire 42 is located closer to the second flange 22. With this configuration, it is possible to prevent the portion of the second wire 42 from the point TP at which it finally contacts the outer surface of the winding core 11 to the point where it is connected to the fourth external electrode 34 from becoming excessively long. As a result, snagging on other components in the portion from the point TP at which it finally contacts the outer surface of the winding core 11 to the point where it is connected to the fourth external electrode 34 can be suppressed, and breakage of the second wire 42 can be suppressed.

[0069] (9) In the above embodiment, the ninth turn of the second wire 42 has a crossing point with respect to the first wire 41. With this configuration, the balance of stray capacitance before and after the crossing point and before and after the first crossing point 61 can be adjusted, and the electrical characteristics are improved.

[0070] <Example of changes> The above embodiments and the following modifications can be combined and implemented to the extent that they do not conflict with each other technically.

[0071] <Examples of changes related to coil components> In the above embodiment, the top plate 10F of the coil component 10 can be omitted. Also, the various dimensions of the coil component 10 are not limited to the examples in the above embodiment.

[0072] The shape of the winding core 11 is not limited to the examples of the above embodiment. For example, the shape of the winding core 11 may be cylindrical, or it may be a polygonal prism other than a rectangular prism. The configuration of the drum core 10C is not limited to the examples of the above embodiments. For example, the first flange portion 21 and the second flange portion 22 do not have to protrude in the third positive direction Z1 in the central portion along the second axis Y. For example, the first flange portion 21 and the second flange portion 22 may be recessed in the central portion along the second axis Y and have a bifurcated shape.

[0073] The method of connecting the joint JP of the external electrode 30 to the wire ends of each wire is not limited to thermocompression bonding. For example, the wire ends of each wire may be joined to the joint JP by a laser, or by other methods.

[0074] The material and shape of the external electrode 30 are not limited to the examples of the above embodiment. The external electrode 30 only needs to be connectable to the first wire 41 and the second wire 42. For example, the external electrode 30 may have a metal layer and a plating layer, to which each wire is connected.

[0075] <Examples of changes related to wires> The number of turns of the first wire 41 and the second wire 42 is not limited to 21 turns. Furthermore, the number of turns of the first winding section 51 and the second winding section 52 are not limited to the examples in the above embodiment.

[0076] For example, in the example shown in Figure 5, the 1.0 turn of the second wire 42 is wound directly around the outer surface of the core 11 without going through the first wire 41. Specifically, the first turn of the second wire 42 is located on the first negative direction X2 side relative to the first turn of the first wire 41. Then, from the second turn to the fifteenth turn, the second wire 42 is wound around the outer surface of the first wire 41.

[0077] Furthermore, in the example shown in Figure 5, the second wire 42 moves from the outer surface of the first wire 41 to the outer surface of the winding core 11 midway through the 16th turn. At the 17.0th turn of the second wire 42, it is located on the outer surface of the winding core 11. In the example shown in Figure 5, the end point EP of the first winding section 51 is located before the 17.0th turn. That is, in the example shown in Figure 5, the first winding section 51 extends from the 2nd turn to the 16th turn. In addition, in the example shown in Figure 5, similar to the embodiment described above, the 16th turn of the second wire 42 crosses the first wire 41. That is, in the example shown in Figure 5, the first winding section 51 has a first crossing point 61 that straddles the first wire 41 without reaching the same layer of the first wire 41 in the section from the end point EP to one turn before.

[0078] In the example shown in Figure 5, on the outer surface of the winding core 11, both the first turn of the first wire 41 and the second turn of the second wire 42 exist before the second turn of the first wire 41. In this way, the first turn of the two wires can restrict the displacement of the first wire 41 toward the first positive direction X1 from the second turn onward, thus suppressing the occurrence of winding collapse of the first wire 41 and the second wire 42 from the second turn onward.

[0079] The second wire 42 can omit the first crossing point 62. For example, the first crossing point 62 can be appropriately selected depending on the number of crossings and transverses and the direction of the crossings and transverses in the section where each wire is drawn out from the winding core 11 and reaches the external electrode 30.

[0080] The direction in which the second wire 42 crosses the first wire 41 along the central axis 11C at the first crossing point 61 and the direction in which the second wire 42 crosses the first wire 41 along the central axis 11C at the first intersection point 62 may be the same. This crossing direction can be appropriately changed depending on whether or not the wires cross and the direction in which they cross at the crossing point.

[0081] When viewing the coil component 10 facing the second positive direction Y1, the second wire 42 does not necessarily have to intersect the first wire 41 near its 1.0 turn. If the second wire 42 has multiple pairs of crossing points where it crosses the first wire 41 in different directions, the twisting of the wire as a whole is eliminated.

[0082] The second wire 42 may have further crossing points at locations other than the first crossing point 62 in the above embodiment. Also, the second wire 42 may have further crossing points at locations other than the first crossing point 61 in the above embodiment.

[0083] The positions of the first intersection point 62 along the central axis 11C, along the second axis Y, and along the third axis Z are not limited to the examples of the above embodiment. That is, the first intersection point 62 may be located on an outer surface of the winding core 11 other than the surface facing the third positive direction Z1. As a result, the first intersection point 62 may be located on an outer surface of the winding core 11 in a direction different from the direction in which the external electrodes 30 are located at each flange. The same applies to the first crossing point 61.

[0084] The first winding portion 51 does not necessarily have to be located on the side of the first flange portion 21 relative to the center C of the winding core portion 11 in the direction along the central axis 11C. That is, the first winding portion 51 may also extend to the side of the second flange portion 22 relative to the center C of the winding core portion 11 in the direction along the central axis 11C.

[0085] The first winding section 51 does not necessarily include a portion TL on the outer circumference side of the first wire 41 where the second wire 42 is wound over two or more layers. In other words, the first winding section 51 does not necessarily have a third layer.

[0086] The second winding section 52 does not necessarily have a portion PA that is spaced apart from adjacent wires in the direction along the central axis 11C. When the second wire 42 is traced from the first wire end 42A to the second wire end 42B, the point TP at which it last contacts the outer surface of the winding core 11 is not limited to the position of region AP, which is closest to the second flange 22 among the three regions. In other words, the point TP at which it last contacts the outer surface of the winding core 11 may be located in the other two regions.

[0087] At the first intersection point 62, the first wire 41 may cross over the second wire 42 from the outer side. In other words, as long as the turn immediately preceding the final turn of the first wire 41 and the turn immediately preceding the final turn of the second wire 42 intersect each other, it does not matter which wire is located on the outer side at the first intersection point 62.

[0088] <Note> The technical concepts that can be derived from the above embodiments and modifications are described below. [1] A drum core having a columnar winding core, a first flange connected to a first end in a direction along the central axis of the winding core, and a second flange connected to a second end of the winding core opposite to the first end; a first external electrode and a second external electrode located on the surface of the first flange; a third external electrode and a fourth external electrode located on the surface of the second flange; a first wire wound around the winding core, with its first end connected to the first external electrode and its second end connected to the third external electrode; a second wire wound around the winding core in the same direction as the first wire, with its first end connected to the second external electrode and its second end connected to the fourth external electrode, wherein the number of turns of the first wire increases by 1 for each full rotation around the central axis from the first end toward the second end of the second wire, and the number of turns of the second wire increases by 1 for each full rotation from the first end toward the second end of the second wire. The number of turns increases by one for each revolution around the central axis toward the wire end, and the second wire comprises a first winding portion wound around the outer circumference of the first wire over multiple turns, and a second winding portion located toward the second wire end than the first winding portion, with at least a portion wound around the outer surface of the winding core, and the range in which it is continuously wound around the outer circumference of the first wire being less than 1.0 turn, wherein when the second wire is traced from the first wire end to the second wire end in the first winding portion, the position of the first winding portion furthest toward the second wire end is defined as the end point of the first winding portion, and the first winding portion has a first crossing point that straddles the first wire without reaching the same layer of the first wire in the section from the end point to the point one turn prior.

[0089] [2] The coil component according to [1], wherein the first winding portion is located on the side of the first flange portion relative to the center of the winding core portion in the direction along the central axis. [3] The coil component according to [1] or [2], wherein the first winding portion includes a portion on the outer circumference side of the first wire in which the second wire is wound over two or more layers.

[0090] [4] When tracing from the first wire end to the second wire end, the final turn includes the point where the winding core last comes into contact with the outer surface of the winding core, and the second winding portion includes the final turn of the second wire, and the turn immediately preceding the final turn of the first wire and the turn immediately preceding the final turn of the second wire have a first intersection point where they intersect each other, as described in any one of [1] to [3].

[0091] [5] The coil component according to [4], wherein, when a specific direction perpendicular to the central axis is defined as the positive direction, the first external electrode and the second external electrode are located on the positive-direction side surface of the first flange with respect to the central axis, the third external electrode and the fourth external electrode are located on the positive-direction side surface of the second flange with respect to the central axis, and the first intersection point is located on the positive-direction side outer surface of the winding core with respect to the central axis.

[0092] [6] The coil component according to [4] or [5], wherein when the second wire is traced from the first wire end to the second wire end, the direction in which the second wire crosses the first wire along the central axis at the first crossing point is opposite to the direction in which the second wire crosses the first wire along the central axis at the first intersection point.

[0093] [7] The coil component according to any one of [1] to [6], wherein the second winding portion has portions that are spaced apart from adjacent wires on at least one side in the direction along the central axis.

[0094] [8] When the winding core is divided into three equal regions in the direction along the central axis, the point at which the second wire is traced from the first wire end to the second wire end and finally contacts the outer surface of the winding core is located in the region closest to the second flange among the three regions, as described in any one of [1] to [7]. [Explanation of Symbols]

[0095] AP…area 10…Coil components 10C... Drum core 11…Core section 11C…Central axis 21...First guard section 22...Second guard section 31...First external electrode 32…Second external electrode 33…Third external electrode 34...Fourth external electrode 41…First wire 42…Second wire 51...Volume 1 Chapter 52...Volume 2 61...First crossing point 62...First intersection

Claims

1. A drum core having a columnar winding core, a first flange connected to a first end in the direction along the central axis of the winding core, and a second flange connected to a second end of the winding core opposite to the first end, The first external electrode and the second external electrode are located on the surface of the first flange portion, The third external electrode and the fourth external electrode located on the surface of the second flange portion, A first wire is wound around the aforementioned core, with its first end connected to the first external electrode and its second end connected to the third external electrode, A second wire is wound around the core in the same direction as the first wire, with its first end connected to the second external electrode and its second end connected to the fourth external electrode, Equipped with, The number of turns increases by one each time the first wire is turned around the central axis, from the first wire end towards the second wire end. The number of turns of the second wire increases by one each time it completes a full rotation around the central axis, moving from the first wire end towards the second wire end. The first wire is wound directly around the core portion without passing through the second wire over its entire circumference. The second wire is A first winding portion that is wound around the outer circumference of the first wire over multiple turns, A second winding portion is located closer to the second wire end than the first winding portion, and at least a portion of it is wound around the outer surface of the winding core portion, and the range in which it is continuously wound around the outer surface of the first wire is less than 1.0 turn, Equipped with, When the second wire is traced from the first wire end to the second wire end in the first winding section, and the position closest to the second wire end within the first winding section is defined as the end point of the first winding section, the first winding section has a first crossing point that straddles the first wire without reaching the same layer of the first wire in the section from the end point up to the point one turn prior. Coil components.

2. The first winding portion is located on the side of the first flange portion relative to the center of the winding core portion in the direction along the central axis. The coil component according to claim 1.

3. The first winding portion includes a portion on the outer circumference of the first wire in which the second wire is wound over two or more layers. The coil component according to claim 1.

4. When tracing from the first end of the wire to the second end of the wire, the final turn is defined as the turn that includes the point where the wire last makes contact with the outer surface of the winding core. The second winding portion includes the final turn of the second wire, The turn immediately preceding the final turn of the first wire and the turn immediately preceding the final turn of the second wire have a first intersection point where they cross each other. The coil component according to claim 1.

5. When a specific direction perpendicular to the aforementioned central axis is defined as the positive direction, The first external electrode and the second external electrode are located on the surface of the first flange portion on the positive side with respect to the central axis. The third external electrode and the fourth external electrode are located on the surface of the second flange portion on the positive side with respect to the central axis. The first intersection point is located on the outer circumferential surface of the winding core portion on the positive side with respect to the central axis. The coil component according to claim 4.

6. When the second wire is traced from the first wire end to the second wire end, the direction in which the second wire crosses the first wire along the central axis at the first crossing point is opposite to the direction in which the second wire crosses the first wire along the central axis at the first intersection point. The coil component according to claim 4.

7. The second winding portion has a portion that is spaced apart from adjacent wires on at least one side in the direction along the central axis. The coil component according to claim 1.

8. When the winding core is divided into three equal regions along the central axis, the point where the second wire, when traced from the first wire end to the second wire end, finally contacts the outer surface of the winding core is located in the region closest to the second flange among the three regions. The coil component according to claim 1.

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