Coil parts
The coil component design addresses wire coating deterioration and current leakage by optimizing electrode placement and wire winding to reduce electric fields, enhancing voltage resistance.
Patent Information
- Application Number
- JP2025062438
- Authority / Receiving Office
- JP · JP
- Patent Type
- Patents
- Current Assignee / Owner
- Filing Date
- 2025-04-04
- Publication Date
- 2026-02-03
- Estimated Expiration
- 2042-09-09
AI Technical Summary
The existing coil components face issues with wire coating deterioration and potential current leakage due to heat-induced degradation and large electric fields generated between adjacent wire turns during thermocompression bonding, leading to reduced voltage resistance characteristics.
A coil component design featuring a drum core with specific electrode placements and wire winding directions that minimize the proximity of wire turns, reducing electric fields and preventing insulation deterioration.
The design effectively suppresses the deterioration of voltage resistance characteristics by minimizing electric fields between wire turns, ensuring reliable coil performance.
Smart Images
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Abstract
Description
[Technical Field]
[0001] The present invention relates to a coil component. [Background technology]
[0002] The coil component described in Patent Document 1 includes a winding core and two flanges. The winding core is rectangular prism-shaped. The two flanges are connected to both ends of the winding core. Each flange protrudes outward from the winding core in a direction perpendicular to the central axis of the winding core. The winding core and flanges are made of a magnetic material. The winding core and flanges form the core of the coil component. The coil component also includes first to fourth electrodes. The first and second electrodes are located on the upper surface of one of the flanges. The third and fourth electrodes are located on the upper surface of the other flange.
[0003] The coil component includes a first wire and a second wire. The first wire and the second wire are coated conductors. The first wire is wound around a winding core. The second wire is wound around the winding core. A first wire end of the first wire is thermocompression bonded to a first electrode. A second wire end of the first wire is thermocompression bonded to a third electrode. A first wire end of the second wire is thermocompression bonded to a second electrode. A second wire end of the second wire is thermocompression bonded to a fourth electrode. When the number of turns of each wire increases by one each time it goes around the winding core from the first wire end side to the second wire end side, the first turn of the first wire and the first turn of the second wire are adjacent to each other in a direction along the central axis of the winding core. [Prior art documents] [Patent documents]
[0004] [Patent Document 1] Japanese Patent Application Laid-Open No. 2017-11288 Summary of the Invention [Problem to be solved by the invention]
[0005] In the coil component described in Patent Document 1, the electrodes and wires are bonded together by thermocompression. During this thermocompression bonding, the coating film of each wire may be affected by heat and deteriorate. In particular, the portion of each wire close to the electrode is susceptible to heat.
[0006] Furthermore, if a potential difference occurs between the first wire and the second wire at a location where the first wire and the second wire are adjacent to each other, a relatively large electric field is generated between the two wires. If the location where the wire coating film is deteriorated coincides with the location where a large electric field is generated between the two wires, current leakage may occur at that location. In other words, the voltage resistance characteristics of the coil component may be reduced.
[0007] Although the above example has been described in which the wire is thermocompression bonded to the electrode, if the coating film can be deteriorated when the wire is connected to the electrode, the same problem will arise regardless of the connection mode. [Means for solving the problem]
[0008] In order 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 of the winding core in a direction along the central axis, and a second flange connected to a second end of the winding core on the opposite side to the first end, and a first electrode located on the outer surface of the first flange in the negative direction relative to the central axis, when a specific direction perpendicular to the central axis is defined as a positive direction and a direction opposite to the positive direction is defined as a negative direction. a second electrode located on the positive side of the central axis on the outer surface of the second flange; a third electrode located on the positive side of the central axis on the outer surface of the second flange; a fourth electrode located on the negative side of the central axis on the outer surface of the second flange; a first wire wound around the winding core, with a first wire end connected to the first electrode and a second wire end connected to the third electrode; and a second wire wound around the winding core in the same direction as the first wire, with a first wire end connected to the second electrode and a second wire end connected to the fourth electrode, When the wire is traced from the first wire end to the second wire end, the point where the wire first comes into contact with the outer peripheral surface of the winding core is defined as a 1.0 turn point of the first wire, and the number of turns of the first wire increases by one for each full revolution around the central axis from the first wire end toward the second wire end; when the second wire is traced from the first wire end to the second wire end, the point where the angular position about the central axis first matches the angular position of the 1.0 turn point of the first wire is defined as a 1.0 turn point of the second wire, and the number of turns of the second wire increases by one for each full revolution around the central axis from the first wire end toward the second wire end; the 1.0 turn point of the first wire is located on the negative side of the central axis, and a 2.0 turn point of the second wire is located between the 1.0 turn point of the first wire and the 1.0 turn point of the second wire in the direction along the central axis.
[0009] In the above configuration, depending on the direction of the current flowing through each wire, a relatively large potential difference occurs between the 1.0 turn of the first wire and the 1.0 turn of the second wire. In the above configuration, the electric field generated between the 1.0 turn of each wire is smaller than in a configuration in which the 1.0 turn of the first wire and the 1.0 turn of the second wire are wound adjacent to each other. As a result, it is possible to prevent a decrease in the withstand voltage characteristics of the coil component. [Effects of the Invention]
[0010] Suppresses the deterioration of the voltage resistance characteristics of coil components. [Brief explanation of the drawings]
[0011] [Figure 1] FIG. 1 is a perspective view of a coil component. [Figure 2] FIG. 2 is a plan view of the coil device when viewed in the third negative direction. [Figure 3] FIG. 3 is a side view of the coil device when viewed in the second positive direction. [Figure 4] FIG. 4 is a plan view of the coil device when viewed in the third positive direction. [Figure 5] FIG. 5 is a side view of the coil device when viewed in the second negative direction. [Figure 6] FIG. 6 is a partial cross-sectional view of the coil component, taken along a cross section including the central axis of the winding core, the 1.0 turn position of the first wire, and the 1.0 turn position of the second wire. DETAILED DESCRIPTION OF THE INVENTION
[0012] Hereinafter, an embodiment of a coil component will be described. Note that the drawings may show components enlarged to facilitate understanding. The dimensional ratios of the components may differ from those in the actual product or from those shown in other drawings.
[0013] <Overall structure> As shown in FIG. 1, the coil device 10 includes a drum core 10C and a top plate 12.
[0014] The drum core 10C has a winding core portion 11, a first flange portion 20, and a second flange portion 30. The winding core 11 has a quadrangular prism shape. A cross section perpendicular to the central axis C of the winding core 11 is rectangular. Note that the "rectangular shape" referred to here is sufficient as long as it has four sides and is rectangular overall, and also includes shapes with chamfered corners of a rectangle. The material of the winding core 11 is a non-conductive material. Specifically, the material of the winding core 11 is, for example, alumina, Ni-Zn ferrite, resin, or a mixture thereof.
[0015] Here, a specific axis parallel to the central axis C of the winding core 11 is referred to as the first axis X. A specific axis perpendicular to the first axis X is referred to 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 referred to 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 referred to as the first positive direction X1, and the direction opposite to the first positive direction X1 is referred to as the first negative direction X2. Similarly, one of the directions along the second axis Y is referred to as the second positive direction Y1, and the direction opposite to the second positive direction Y1 is referred to as the second negative direction Y2. One of the directions along the third axis Z is defined as a third positive direction Z1, and the direction opposite to the third positive direction Z1 is defined as a third negative direction Z2.
[0016] As shown in FIG. 1 , the first flange 20 is connected to a first end, which is the end of the winding core 11 in the first positive direction X1. The first flange 20 has a generally rectangular plate shape that is flattened in the direction along the first axis X. When viewed in the direction along the first axis X, each side of the first flange 20 is parallel to each side of the winding core 11. Furthermore, the first flange 20 protrudes outward relative to the winding core 11 in the direction along the second axis Y and the direction along the third axis Z.
[0017] Here, the surface of the first flange 20 facing the first positive direction X1 is referred to as a first outer end surface 22, and the surface facing the first negative direction X2 is referred to as a first inner end surface 23. Furthermore, the surface of the first flange 20 facing the second positive direction Y1 is referred to as a first side surface 24, and the surface facing the second negative direction Y2 is referred to as a second side surface 25. Furthermore, the surface of the first flange 20 facing the third positive direction Z1 is referred to as a first bottom surface 26, and the surface facing the third negative direction Z2 is referred to as a first top surface 27.
[0018] The first outer end surface 22 and the first inner end surface 23 are surfaces that are perpendicular to the central axis C. The first bottom surface 26 and the first top surface 27 are surfaces that are parallel to the central axis C. The first bottom surface 26 and the first top surface 27 are also surfaces that are parallel to the mounting surface that faces the substrate when the coil component 10 is mounted on the substrate. The first side surface 24 and the second side surface 25 are surfaces that are parallel to the central axis C and perpendicular to the first bottom surface 26.
[0019] The first flange 20 has a recess 21. The recess 21 is recessed relative to a first bottom surface 26 of the first flange 20. The recess 21 is open to both sides of the first flange 20 in the direction along the first axis X. As a result, the first bottom surface 26 of the first flange 20 is divided into two parts with the recess 21 in between. The first flange 20 has a symmetrical shape in the direction along the second axis Y.
[0020] The second flange portion 30 is connected to a second end, which is the end on the first negative direction X2 side, of the winding core portion 11. The second flange portion 30 has a symmetrical shape to the first flange portion 20 in the direction along the first axis X. That is, the second flange portion 30 has a substantially rectangular plate shape.
[0021] Here, the surface of second flange 30 facing the first negative direction X2 is referred to as a second outer end surface 32, and the surface facing the first positive direction X1 is referred to as a second inner end surface 33. Furthermore, the surface of second flange 30 facing the second positive direction Y1 is referred to as a third side surface 34, and the surface facing the second negative direction Y2 is referred to as a fourth side surface 35. Furthermore, the surface of second flange 30 facing the third positive direction Z1 is referred to as a second bottom surface 36, and the surface facing the third negative direction Z2 is referred to as a second top surface 37.
[0022] The second outer end surface 32 and the second inner end surface 33 are planes perpendicular to the central axis C. The second bottom surface 36 and the second top surface 37 are surfaces parallel to the central axis C. The second bottom surface 36 and the second top surface 37 are also surfaces parallel to the mounting surface that faces the substrate when the coil component 10 is mounted on the substrate. The third side surface 34 and the fourth side surface 35 are surfaces parallel to the central axis C and perpendicular to the second bottom surface 36.
[0023] The second flange portion 30 protrudes outward relative to the winding core portion 11 in the direction along the second axis Y and the direction along the third axis Z. The second flange portion 30 also has a recessed portion 31. The recessed portion 31 is recessed relative to a second bottom surface 36 of the second flange portion 30.
[0024] The first flange 20 and the second flange 30 are made of the same non-conductive material as the winding core 11. The first flange 20 and the second flange 30 are integrally molded with the winding core 11. In this embodiment, the maximum dimension of the drum core 10C along the first axis X is 3.2 mm, the maximum dimension of the drum core 10C along the second axis Y is 2.5 mm, and the maximum dimension of the drum core 10C along the third axis Z is 2.3 mm.
[0025] The top plate 12 has a rectangular plate shape. The top plate 12 is flat in the direction along the third axis Z. The long sides of the top plate 12 are parallel to the first axis X. The short sides of the top plate 12 are parallel to the second axis Y. The top plate 12 is located on the third negative direction Z2 side with respect to the drum core 10C. The top plate 12 is connected to both the first top surface 27 of the first flange portion 20 and the second top surface 37 of the second flange portion 30. In other words, the top plate 12 is bridged between the first flange portion 20 and the second flange portion 30. The top plate 12 is made of the same non-conductive material as the winding core portion 11. Note that the top plate 12 is not shown in Figure 2 and subsequent figures.
[0026] The coil device 10 includes a first electrode 41, a second electrode 42, a third electrode 43, and a fourth electrode 44. The first electrode 41 is located on the outer surface of the first flange portion 20. Specifically, the first electrode 41 is located on the first bottom surface 26. The first electrode 41 is also located on the first bottom surface 26 on the second positive direction Y1 side with respect to the central axis C. Specifically, the first electrode 41 is located on the second positive direction Y1 side with respect to the recessed portion 21.
[0027] The second electrode 42 is located on the outer surface of the first flange portion 20. Specifically, the second electrode 42 is located on the first bottom surface 26. Furthermore, the second electrode 42 is located on the first bottom surface 26 on the side in the second negative direction Y2 with respect to the central axis C. Specifically, the second electrode 42 is located on the side in the second negative direction Y2 with respect to the recessed portion 21.
[0028] The third electrode 43 is located on the outer surface of the second flange 30. Specifically, the third electrode 43 is located on the second bottom surface 36. Furthermore, the third electrode 43 is located on the second bottom surface 36 on the second positive direction Y1 side with respect to the central axis C. Specifically, the third electrode 43 is located on the second positive direction Y1 side with respect to the recessed portion 31.
[0029] The fourth electrode 44 is located on the outer surface of the second flange 30. Specifically, the fourth electrode 44 is located on the second bottom surface 36. Furthermore, the fourth electrode 44 is located on the second bottom surface 36 on the side in the second negative direction Y2 with respect to the central axis C. Specifically, the fourth electrode 44 is located on the side in the second negative direction Y2 with respect to the recessed portion 31.
[0030] These first to fourth electrodes 41 to 44 have a metal layer and a plating layer. The material of the metal layer is silver. The metal layer is formed on the outer surface of the first flange portion 20 or the second flange portion 30. The plating layer consists of three layers. The plating layer is formed by stacking copper, nickel, and tin on the surface of the metal layer in this order. In FIG. 1, the boundaries between the metal layer and the plating layer are not shown. The end face of the coil component 10 on the third positive direction Z1 side is the mounting surface that faces the substrate when the coil component 10 is mounted on the substrate.
[0031] <Regarding the first and second wires> As shown in FIG. 1, the coil device 10 includes a first wire 51 and a second wire 52. The first wire 51 and the second wire 52 are wound around a winding core 11. Although not shown, the first wire 51 includes a copper wire and an insulating coating. The insulating coating covers the outer surface of the copper wire. The first wire 51 has a substantially circular shape in a cross section perpendicular to the direction in which the first wire 51 extends. The outer diameter of the first wire 51 is approximately 100 μm. The second wire 52 has the same configuration as the first wire 51. That is, the second wire 52 includes a copper wire and an insulating coating. The outer diameter of the second wire 52 is approximately 100 μm. In FIG. 1, the first wire 51 is colored with dots.
[0032] 2, a first wire end 51A of the first wire 51 is connected to the first electrode 41. A second wire end 51B of the first wire 51 is connected to the third electrode 43. The first wire end 51A and the second wire end 51B are connected to the corresponding electrodes by thermocompression bonding.
[0033] Here, when tracing the first wire 51 from the first wire end 51A to the second wire end 51B, the point where the first wire 51 first comes into contact with the outer circumferential surface of the winding core 11 is defined as a 1.0 turn point A1 of the first wire 51. In this embodiment, the 1.0 turn point A1 of the first wire 51 is located on the second negative direction Y2 side and the ridge line on the third positive direction Z1 side of the winding core 11. In other words, the 1.0 turn point A1 of the first wire 51 is located on the second negative direction Y2 side with respect to the central axis C.
[0034] Furthermore, the number of turns of the first wire 51 increases by one each time the first wire 51 makes one revolution around the central axis C from the first wire end 51A to the second wire end 51B. The first wire 51 is wound around the winding core 11 so that the winding progresses clockwise as the number of turns increases when viewed in the first negative direction X2. Therefore, for example, when viewed in the first negative direction X2, a position that progresses 36 degrees around the central axis C from the position A1 of the 1.0 turn of the first wire 51 is the position of the 1.1 turn of the first wire 51.
[0035] A first wire end 52A of the second wire 52 is connected to the second electrode 42. A second wire end 52B of the second wire 52 is connected to the fourth electrode 44. The first wire end 52A and the second wire end 52B are connected to the corresponding electrodes by thermocompression bonding.
[0036] Here, when tracing the second wire 52 from the first wire end 52A to the second wire end 52B, the first point whose angular position about the central axis C matches the angular position of the 1.0 turn point A1 of the first wire 51 is defined as the 1.0 turn point B1 of the second wire 52. That is, in the present embodiment, when viewed in a direction along the first axis X, the 1.0 turn point B1 of the second wire 52 is located on a straight line connecting the ridge line of the winding core 11 on the second negative direction Y2 side and the third positive direction Z1 side with the central axis C. Note that in the present embodiment, when tracing the second wire 52 from the first wire end 52A to the second wire end 52B, the 1.0 turn point B1 of the second wire 52 first comes into contact with the outer circumferential surface of the winding core 11. Note that the 1.0 turn point B1 of the second wire 52 does not have to come into contact with the outer circumferential surface of the winding core 11.
[0037] Furthermore, the number of turns of the second wire 52 increases by one each time the second wire 52 makes one revolution around the central axis C from the first wire end 52A to the second wire end 52B. When viewed in the first negative direction X2, the second wire 52 is wound around the winding core 11 so as to progress clockwise as the number of turns increases. That is, the second wire 52 is wound in the same direction as the first wire 51. A portion of the second wire 52 is wound around the winding core 11 from the outside of the first wire 51. In other words, a portion of the second wire 52 is in contact with the outer surface of the first wire 51 on the side opposite to the central axis C.
[0038] <About the turns of the first and second wires> 3 to 5, the first wire 51 has a 9th turn but does not have a 10th turn. That is, the first wire 51 has a 9.0 turn portion but does not have a 10.0 turn portion. Furthermore, the first wire 51 is wound directly around the outer peripheral surface of the winding core 11 over substantially the entire range from the 1.0 turn portion A1 to the 9.0 turn portion.
[0039] As shown in FIG. 2 , the second wire 52 has a 9th turn but does not have a 10th turn. That is, the second wire 52 has a 9.0 turn portion but does not have a 10.0 turn portion. The second wire 52 is wound around the outer circumferential surface of the winding core 11 from the 1.0 turn portion B1 to the middle of the second turn. The second wire 52 is in contact with the first wire 51 from the outside over substantially the entire range from the middle of the second turn to the 9.0 turn portion. The "second turn" refers to a range of 2.0 turns or more and less than 3.0 turns of the wire. The same applies to other numerical values.
[0040] The second wire 52 has a first intersection point CP1 that intersects, from the outside, a portion of the first wire 51 from the first wire end 51A to the 1.0 turn point A1. The first intersection point CP1 is located within a range of 1.0 turn or more and less than 2.0 turns of the second wire 52. Specifically, the first intersection point CP1 is located at approximately 1.8 turns of the second wire 52. The first intersection point CP1 is located on the second negative direction Y2 side of the central axis C. In this embodiment, the "intersection point" refers to a point where the center line of the second wire 52 crosses the center line of the first wire 51 when viewed in a direction perpendicular to the outer circumferential surface of the winding core 11, i.e., in the third negative direction Z2.
[0041] 3, the 2.0 turn portion B2 of the second wire 52 is adjacent to the 1.0 turn portion B1 of the second wire 52 in the direction along the central axis C. The 2.0 turn portion B2 of the second wire 52 is located between the 1.0 turn portion A1 of the first wire 51 and the 1.0 turn portion B1 of the second wire 52 in the direction along the central axis C. In other words, the 1.0 turn portion A1 of the first wire 51 is spaced apart from the 1.0 turn portion B1 of the second wire 52 in the direction along the central axis C.
[0042] As shown in FIGS. 2 to 5, the range of 1.0 turn or more and less than 2.0 turns of the first wire 51 is separated from the range of 1.0 turn or more and less than 2.0 turns of the second wire 52.
[0043] Here, when tracing the second wire 52 from the first wire end 52A to the second wire end 52B, the location where the second wire 52 first runs onto the outside of the portion of the first wire 51 after the 1.0 turn point A1 is defined as the initial run-on location F. The initial run-on location F is located within a range of 2.0 turns or more and less than 3.0 turns of the second wire 52. Specifically, the initial run-on location F is located at approximately 2.7 turns of the second wire 52. In this embodiment, the location where the center line of the second wire 52 first moves outward from the center line of the first wire 51 is defined as the outward run-on location. The "center line of the wire" refers to a line passing through the geometric center of a cross section perpendicular to the extension direction of the wire. In other words, at the portion of the wire wound around the winding core 11, the center line of the wire extends in the winding direction. The "outside" in this description corresponds to the outside in the circumferential direction around the central axis C.
[0044] 2, the second wire 52 has a second intersection point CP2 that intersects from the outside with respect to a portion of the first wire 51 from the 1.0 turn point A1 to the 2.0 turn point. The second intersection point CP2 is located within a range of 2.0 turns or more and less than 3.0 turns of the second wire 52. Specifically, the second intersection point CP2 is located at approximately 2.9 turns of the second wire 52.
[0045] 6, the coil device 10 is viewed in cross section along a cross section including the central axis C, the 1.0 turn portion A1 of the first wire 51, and the 1.0 turn portion B1 of the second wire 52. In the direction along the central axis C, from the first flange portion 20 side to the second flange portion 30 side, the 1.0 turn portion B1 of the second wire 52, the 2.0 turn portion B2 of the second wire 52, the 1.0 turn portion A1 of the first wire 51, and the 2.0 turn portion of the first wire 51 are arranged in this order.
[0046] Furthermore, on the same cross section, in the direction along the central axis C, the 3.0 turn portion of the second wire 52 is located between the 2.0 turn portion and the 3.0 turn portion of the first wire 51. In addition, in the direction along the central axis C, the 4.0 turn portion of the second wire 52 is located between the 3.0 turn portion and the 4.0 turn portion of the first wire 51. Similarly, the subsequent turns of the second wire 52 are wound between adjacent turns of the first wire 51. In other words, when N is an integer equal to or greater than 3 and less than 9, in the direction along the central axis C, the N turn portion of the second wire 52 is located between the (N-1) turn portion and the N turn portion of the first wire 51.
[0047] <Manufacturing method for coil components> The method for manufacturing the coil device 10 includes a preparation step, a first step, and a second step. In the preparation step, the drum core 10C having the first to fourth electrodes 41 to 44 is prepared as follows.
[0048] First, in the preparation process, the drum core 10C is formed. First, ferrite powder is mixed with a synthetic resin binder, and the molded body formed by press molding is fired. Then, burrs are removed from the molded body using a barrel, forming the drum core 10C. Next, a paste containing silver is baked onto the first bottom surface 26 of the first flange portion 20 and the second bottom surface 36 of the second flange portion 30 of the drum core 10C. Each electrode is formed by plating the paste with copper, nickel, and tin, in that order.
[0049] Next, in the first step, the first wire 51 is wound around the winding core 11 from the first flange 20 side toward the second flange 30 side. Then, the first wire end 51A of the first wire 51 is thermocompression bonded to the first electrode 41. Also, the second wire end 51B of the first wire 51 is thermocompression bonded to the third electrode 43. At this time, the insulating coating near the first wire end 51A of the first wire 51 may peel off. Similarly, the insulating coating near the second wire end 51B of the first wire 51 may peel off.
[0050] Next, in the second step, the second wire 52 is wound around the outer circumferential side of the winding core 11 and the first wire 51. Specifically, the first turn of the second wire 52 is started to be wound around the outer circumferential surface of the winding core 11. Then, midway through the first turn of the second wire 52, the second wire 52 is wound from the outside of the first wire 51 in a section from the first wire end 51A of the first wire 51 to the 1.0 turn point A1 of the first wire 51. This forms a first intersection point CP1. Next, a part of the second turn of the second wire 52 is wound around the outer circumferential surface of the winding core 11. Then, midway through the second turn of the second wire 52, the second wire 52 is caused to ride up onto the outside of the first turn of the first wire 51. This forms an initial ride-up point F. Then, midway through the second turn of the second wire 52, the second wire 52 is wound while moving closer to the second flange 30, thereby causing the second wire 52 to cross the first wire 51 again. This forms the second intersection point CP2. Then, the third and subsequent turns of the second wire 52 are wound around the outside of the first wire 51. Then, the first wire end 52A of the second wire 52 is thermocompression bonded to the second electrode 42. Also, the second wire end 52B of the second wire 52 is thermocompression bonded to the fourth electrode 44. At this time, the insulating coating near the first wire end 52A of the second wire 52 may peel off. Similarly, the insulating coating near the second wire end 52B of the second wire 52 may peel off.
[0051] <Effects of this embodiment> (1) In a common mode choke coil such as that of the above embodiment, depending on the direction of the current flowing through the first wire 51 and the second wire 52, a relatively large potential difference occurs between the 1.0 turn portion A1 of the first wire 51 and the 1.0 turn portion B1 of the second wire 52. In the above embodiment, the electric field generated between the 1.0 turn portions of the wires is smaller than in a configuration in which the 1.0 turn portion A1 of the first wire 51 and the 1.0 turn portion B1 of the second wire 52 are wound adjacent to each other. As a result, a decrease in the withstand voltage characteristics of the coil device 10 can be suppressed.
[0052] In particular, when the wire ends of each wire are connected to electrodes by thermocompression bonding, the insulating coating of the wire may deteriorate near the wire ends. In some cases, the deterioration of the insulating coating may extend to the 1.0 turn of each wire. In other words, when the wire ends of the wires are connected by thermocompression bonding, the location where the insulating coating has deteriorated is likely to coincide with the location where a large electric field is generated between the two wires. Thus, the configuration of the above embodiment is particularly useful for coil components 10 that are manufactured using thermocompression bonding.
[0053] (2) In the above embodiment, the range of 1.0 turn or more and less than 2.0 turns of the first wire 51 is separated from the range of 1.0 turn or more and less than 2.0 turns of the second wire 52. In other words, in this configuration, the wires are not in contact over a wide range, including the entire first turn of the first wire 51 and the entire first turn of the second wire 52. This makes it possible to more effectively reduce the electric field generated between the two wires.
[0054] (3) In the above embodiment, the 2.0 turn portion B2 of the second wire 52 is located between the 1.0 turn portion B1 of the second wire 52 and the 1.0 turn portion A1 of the first wire 51 in the direction along the central axis C. Therefore, even if the 1.0 turn portion B1 of the second wire 52 attempts to move in the direction along the central axis C, the 1.0 turn portion B1 of the second wire 52 is restricted by the 2.0 turn portion B2 of the second wire 52. In other words, the 1.0 turn portion B1 of the second wire 52 is unlikely to move in a direction approaching the 1.0 turn portion A1 of the first wire 51. According to the above configuration, the 1.0 turn portion A1 of the first wire 51 and the 1.0 turn portion B1 of the second wire 52 can be reliably separated from each other.
[0055] (4) Compared to a configuration in which the same turns of the first wire 51 and the second wire 52 are wound apart, a configuration in which the same turns of both wires are wound adjacent to each other results in a higher frequency at which the impedance is maximized. According to the above embodiment, from the third turn onwards, the same turns of each wire are wound adjacent to each other. That is, with the above configuration, preferable impedance characteristics can be obtained, particularly in the high frequency range.
[0056] (5) In the above embodiment, the initial ride-on point F is located within a range of 2.0 turns or more and less than 3.0 turns of the second wire 52. In other words, the second wire 52 is wound outward relative to the first wire 51 at an early stage after the 2.0 turn point B2. With this configuration, there is no need to ensure a large space on the outer circumferential surface of the winding core 11 for winding the second wire 52.
[0057] (6) In the above embodiment, the first intersection point CP1 is located within a range of 1.0 turn or more and less than 2.0 turns of the second wire 52. According to the above configuration, the 2.0 turn point B2 of the second wire 52 can be reliably positioned between the 1.0 turn point A1 of the first wire 51 and the 1.0 turn point B1 of the second wire 52.
[0058] (7) In the above embodiment, the first intersection point CP1 is located on the second negative direction Y2 side with respect to the central axis C. According to the above configuration, compared to a configuration in which the first intersection point CP1 is located on the second positive direction Y1 side with respect to the central axis C, the first intersection point CP1 is located at a position closer to the winding core 11. By locating the first intersection point CP1 at a position closer to the winding core 11, the position of the first intersection point CP1 is less likely to shift.
[0059] <Example of change> This embodiment can be modified as follows: This embodiment and the following modifications can be combined and implemented within the scope of technical compatibility.
[0060] The configuration of the coil device 10 is not limited to the above embodiment. For example, the top plate 12 of the coil device 10 may be omitted. Furthermore, the shape of the first flange portion 20 is not limited to the shape of the above embodiment. For example, the recessed portion 21 of the first flange portion 20 may be omitted.
[0061] In the above embodiment, the winding core 11 does not have to be a rectangular prism. For example, the cross-sectional shape of the winding core 11 may be a circle, an ellipse, or a polygon other than a rectangle. In the above embodiment, the ridge lines of the winding core 11 may be chamfered. That is, the boundary between the outer circumferential surfaces includes a curved surface formed by, for example, rounding the corners that form adjacent flat surfaces.
[0062] In the above embodiment, the shape and dimensions of the drum core 10C are not limited to the examples in the above embodiment. In the above-described embodiment, the material of each electrode is not limited to the example of the above-described embodiment. For example, the material of the plating layer of each electrode may be a nickel alloy. Alternatively, each electrode may not have a plating layer, and a conductive metal layer may be exposed. Alternatively, each electrode may be a plate-shaped metal terminal.
[0063] In the above embodiment, the outer diameters of the first wire 51 and the second wire 52 are not limited to the examples in the above embodiment. In the above embodiment, the position of the first intersection point CP1 is not limited to the example in the above embodiment. For example, the first intersection point CP1 may be located on the second positive direction Y1 side with respect to the central axis C. Furthermore, the second wire 52 may not have the first intersection point CP1. That is, the 2.0 turn point B2 of the second wire 52 may be located on the first negative direction X2 side with respect to the 1.0 turn point A1 of the first wire 51.
[0064] In the above embodiment, the initial run-on point F is not limited to the position in the above embodiment. That is, the initial run-on point F may be located less than the point B2 of 2.0 turns of the second wire 52, or may be located at a point of 3.0 turns or more of the second wire 52.
[0065] The second wire 52 does not have to have a portion wound around the first wire 51 from the outside. For example, the first wire 51, the second wire 52, the first wire 51, the second wire 52, ... may be alternately positioned on the outer circumferential surface of the winding core 11 in the direction along the central axis C. Even in this case, the effect of (1) can be obtained as long as the 1.0 turn portion A1 of the first wire 51 and the 1.0 turn portion B1 of the second wire 52 are separated from each other.
[0066] In the above embodiment, the 3.0-turn portion of the second wire 52 does not have to be located between the 2.0-turn portion and the 3.0-turn portion of the first wire 51. For example, the 3.0-turn portion of the second wire 52 may be located between the 3.0-turn portion and the 4.0-turn portion of the first wire 51. This also applies to the other turns. To achieve the effect described in (4) above, the following configuration is preferable. When M is a specific integer equal to or greater than 4 and N is an integer equal to or greater than 3 and less than M, the first wire 51 and the second wire 52 each have an M-th turn but do not have an (M+1)-th turn. In this case, it is preferable that the N-th turn portion of the second wire 52 be located between the (N-1)-th turn portion and the N-th turn portion of the first wire 51 in the direction along the central axis C.
[0067] In the above embodiment, a portion of the first wire 51 in the range of 1.0 turn or more and less than 2.0 turns may be in contact with the portion of the second wire 52 in the range of 1.0 turn or more and less than 2.0 turns. If the 1.0 turn portion A1 of the first wire 51 is spaced apart in the direction along the central axis C from the 1.0 turn portion B1 of the second wire 52, the effect of (1) can be obtained.
[0068] In the above embodiment, the 2.0 turn portion B2 of the second wire 52 does not have to be located between the 1.0 turn portion A1 of the first wire 51 and the 1.0 turn portion B1 of the second wire 52 in the direction along the central axis C.
[0069] Furthermore, the winding method of each wire is not important as long as the 1.0 turn portion A1 of the first wire 51 and the 1.0 turn portion B1 of the second wire 52 are spaced apart in the direction along the central axis C. For example, the 1.0 turn portion B1 of the second wire 52 may be located on the first negative direction X2 side of the 1.0 turn portion A1 of the first wire 51. The second or subsequent turn of the first wire 51 or the third or subsequent turn of the second wire 52 may be located between the 1.0 turn portion A1 of the first wire 51 and the 1.0 turn portion B1 of the second wire 52.
[0070] The coil device 10 may be manufactured using steps and in an order different from those in the above embodiment. In the above embodiment, the manufacturing method of the drum core 10C prepared in the preparation step is not limited to the example of the above embodiment. For example, the drum core 10C may be formed by grinding a rectangular parallelepiped ferrite core.
[0071] The technical concepts that can be derived from the above-described embodiments and modifications will be described below. [1] A drum core having a columnar winding core, a first flange connected to a first end of the winding core in a direction along the central axis, and a second flange connected to a second end of the winding core opposite to the first end, and a specific direction perpendicular to the central axis being defined as a positive direction and a direction opposite to the positive direction being defined as a negative direction, a first electrode located on the outer surface of the first flange on the positive side of the central axis, and a second flange connected to the negative side of the central axis on the outer surface of the first flange. a second electrode located on the positive side of the central axis on the outer surface of the second flange; a fourth electrode located on the negative side of the central axis on the outer surface of the second flange; a first wire wound around the winding core, with a first wire end connected to the first electrode and a second wire end connected to the third electrode; and a second wire wound around the winding core in the same direction as the first wire, with a first wire end connected to the second electrode and a second wire end connected to the fourth electrode. a coil device comprising: a first wire; and a 1.0 turn point of the first wire, wherein when the first wire is traced from the first wire end to the second wire end, a point that first comes into contact with the outer peripheral surface of the winding core is defined as a 1.0 turn point of the first wire, and the number of turns of the first wire increases by one for each full revolution around the central axis from the first wire end toward the second wire end; when the second wire is traced from the first wire end to the second wire end, a point whose angular position about the central axis first matches the angular position of the 1.0 turn point of the first wire is defined as a 1.0 turn point of the second wire, and the number of turns of the second wire increases by one for each full revolution around the central axis from the first wire end toward the second wire end; the 1.0 turn point of the first wire is located on the negative side of the central axis and is spaced apart in a direction along the central axis from the 1.0 turn point of the second wire.
[0072] [2] The coil component according to [1], wherein the range of 1.0 turn or more and less than 2.0 turns of the first wire is separated from the range of 1.0 turn or more and less than 2.0 turns of the second wire.
[0073] [3] A coil component according to [1] or [2], wherein, in a direction along the central axis, a 2.0 turn portion of the second wire is located between a 1.0 turn portion of the first wire and a 1.0 turn portion of the second wire.
[0074] [4] A coil component according to any one of [1] to [3], wherein when M is a specific integer equal to or greater than 4 and N is any integer equal to or greater than 3 and less than M, the first wire and the second wire have M turns but not (M+1) turns, and in the direction along the central axis, the N turn of the second wire is located between the (N-1) turn and the N turn of the first wire.
[0075] [5] A coil component according to any one of [1] to [4], wherein when the second wire is traced from the first wire end to the second wire end, the first run-over point is defined as the point where the second wire first runs over the outside of the portion of the first wire after the 1.0 turn point, and the first run-over point is located within a range of 2.0 turns or more and less than 3.0 turns of the second wire.
[0076] [6] A coil component according to any one of [1] to [5], wherein the second wire has an intersection point that crosses the portion of the first wire from the first wire end to a point 1.0 turn from the outside, and the intersection point is located within a range of 1.0 turn or more and less than 2.0 turns of the second wire.
[0077] [7] The coil component according to [6], wherein the intersection is located on the negative side of the central axis. [Explanation of symbols]
[0078] C…Central axis Y...second axis Y1…Second positive direction Y2…Second negative direction 10...Coil parts 10C...Drum core 11...Core 20...First flange 30...Second flange 41...1st electrode 42…Second electrode 43...Third electrode 44…4th electrode 51...First wire 51A…1st line end 51B…Second line end 52...Second wire 52A...First line end 52B...Second line end
Claims
1. a drum core having a columnar winding core, a first flange connected to a first end of the winding core in a direction along a central axis thereof, and a second flange connected to a second end of the winding core opposite to the first end; When a specific direction perpendicular to the central axis is defined as a positive direction and a direction opposite to the positive direction is defined as a negative direction, a first electrode located on the outer surface of the first flange portion on the positive side with respect to the central axis; a second electrode located on the outer surface of the first flange portion on the negative side with respect to the central axis; a third electrode located on the outer surface of the second flange portion on the positive side with respect to the central axis; a fourth electrode located on the outer surface of the second flange portion on the negative side with respect to the central axis; a first wire wound around the winding core, the first wire end connected to the first electrode and the second wire end connected to the third electrode; a second wire wound around the winding core in the same direction as the first wire, the first wire end connected to the second electrode and the second wire end connected to the fourth electrode; Equipped with When tracing the first wire from the first wire end to the second wire end, the point where the first wire first comes into contact with the outer circumferential surface of the winding core is defined as a 1.0 turn point of the first wire, and the number of turns of the first wire increases by one for each full turn around the central axis from the first wire end toward the second wire end, When tracing the second wire from the first wire end to the second wire end, the point where the angular position about the central axis first matches the angular position of the 1.0 turn point of the first wire is defined as the 1.0 turn point of the second wire, and the number of turns of the second wire increases by one for each full rotation around the central axis from the first wire end toward the second wire end, a 1.0 turn point of the first wire is located on the negative side of the central axis and is spaced apart from a 1.0 turn point of the second wire in a direction along the central axis; In a direction along the central axis, a point of 2.0 turns of the second wire is located between a point of 1.0 turn of the first wire and a point of 1.0 turn of the second wire. Coil parts.
2. When M is a specific integer of 4 or more, and N is an arbitrary integer of 3 or more but less than M, the first wire and the second wire have an M-th turn but do not have an (M+1)-th turn, In the direction along the central axis, the N-turn point of the second wire is located between the (N-1)-turn point and the N-turn point of the first wire. The coil component according to claim 1 .
3. When the second wire is traced from the first wire end to the second wire end side, a point where the second wire first runs onto the outside of a portion of the first wire after the point of 1.0 turn is defined as an initial run-up point. The initial ride-over point is present within a range of 2.0 turns or more and less than 3.0 turns of the second wire. The coil component according to claim 1 .
4. the second wire has an intersection point that intersects from outside a portion of the first wire from the first wire end to a point of 1.0 turn, The intersection is present within a range of 1.0 turn or more and less than 2.0 turns of the second wire. The coil component according to claim 1 .
5. The intersection point is located on the negative side of the central axis The coil component according to claim 4 .
Citation Information
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