Coil component

Abstract

[Problem] To provide a coil component which enables closely adjacent mounting without causing short-circuit defects. [Solution] This coil component 1 has: an element body 2 that includes magnetic particles and a resin and that has a first surface 30a; a coil 10 that is located inside the element body 2; and a terminal electrode 40a that has a lead-out part 12a of the coil 10 connected thereto and that comes into contact with an electrode contact part 36a of the first surface 30a. The element body 2 is formed around at least the terminal electrode 40a and has a bulge part 38 that bulges relative to the electrode contact part 36a. The bulge part 38 is located at an outer edge part of the first surface 30a.

Description

Coil parts

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

[0002] Coil components having a coil disposed inside an element body have been known for some time. For example, a coil component disclosed in Patent Document 1 includes an element body, a coil located inside the element body, and terminal electrodes to which lead-out portions of the coil are connected, and functions as an inductor.

[0003] In recent years, as coil components have become smaller and more integrated, the spacing between adjacent coil components on a substrate has tended to become narrower. In the coil component of Patent Document 1, terminal electrodes are formed on the mounting surface of the element body, which facilitates close-adjacent mounting, in which a large number of coil components are mounted on a substrate at narrow intervals.

[0004] Japanese Patent Application Publication No. 11-251177

[0005] When the terminal electrodes are formed on the mounting surface of the element body, it is desirable that measures be taken to prevent short-circuit defects between adjacent coil components or between the coil components and the conductive pattern.

[0006] The present disclosure provides a coil component that allows close-adjacent mounting without causing short-circuit defects.

[0007] A coil component according to one embodiment of the present disclosure comprises: a base body containing magnetic particles and a resin and having a first surface; a coil located inside the base body; and a terminal electrode to which an extractor portion of the coil is connected and which contacts an electrode contact portion on the first surface, wherein the base body has a raised portion formed at least around the terminal electrode and raised relative to the electrode contact portion, and the raised portion is located on the outer edge of the first surface.

[0008] In a coil component according to an embodiment of the present disclosure, the element body has a protruding portion formed at least around the terminal electrode and protruding relative to the electrode contact portion. Therefore, when the terminal electrode is bonded to a mounting substrate (conductive pattern) with a conductive bonding material, the protruding portion serves to prevent the conductive bonding material from flowing out of the terminal electrode (electrode contact portion) around the terminal electrode. The protruding portion also serves to prevent the conductive bonding material from flowing into the terminal electrode around the terminal electrode.

[0009] In particular, in a coil component according to an embodiment of the present disclosure, the raised portion is located on the outer edge of the first surface. Therefore, the raised portion, at the outer edge of the first surface, prevents the conductive bonding material from flowing out from the terminal electrode to the outside of the outer edge of the first surface. This makes it difficult for the conductive bonding material to flow from one coil component to the other coil component between adjacent coil components, thereby preventing the occurrence of short circuits. Furthermore, the raised portion, at the outer edge of the first surface, prevents the conductive bonding material from flowing from the outside of the outer edge of the first surface to the terminal electrode. This makes it difficult for the conductive bonding material to flow from one coil component to the other coil component between adjacent coil components, thereby preventing the occurrence of short circuits.

[0010] Furthermore, the conductive bonding material is less likely to flow in and out between the coil component and the adjacent conductive pattern, making it possible to prevent short circuits from occurring.

[0011] Furthermore, a protrusion containing magnetic particles and resin is formed on the outer edge of the first surface, increasing the volume of the element body, thereby improving the inductance characteristics of the coil component and enhancing the shielding effect against external magnetic fields.

[0012] FIG. 1A is a perspective view of an example of a coil component according to the first embodiment. FIG. 1B is a perspective view of an example of a coil component, schematically illustrating the surface shape of an exterior body. FIG. 1C is a perspective view of the coil component shown in FIG. 1B, viewed from the first surface side. FIG. 1D is a perspective view of an example of a modified version of the coil component shown in FIG. 1C. FIG. 2A is a cross-sectional view of the exterior body shown in FIG. 1A, taken along line IIA-IIA. FIG. 2B is a cross-sectional view of the exterior body shown in FIG. 1A, taken along line IIB-IIB. FIG. 2C is a cross-sectional view of an example of a modified version of the coil component shown in FIG. 2A. FIG. 2D is a cross-sectional view of an example of a modified version of the coil component shown in FIG. 2C. FIG. 2E is a cross-sectional view of an example of a modified version of the coil component shown in FIG. 2C. FIG. 3 is a perspective view of an example of a core provided with a coil and terminal electrodes. FIG. 4A is a bottom view showing variations in the shape of the raised portion shown in FIG. 1C. FIG. 4B is a bottom view showing variations in the shape of the raised portion shown in FIG. 1C. FIG. 5A is a bottom view showing variations in the shape of the raised portion shown in FIG. 1C. FIG. 5B is a bottom view showing variations in the shape of the protrusions shown in FIG. 1C. FIG. 6A is a bottom view showing variations in the shape of the protrusions shown in FIG. 1C. FIG. 6B is a bottom view showing variations in the shape of the protrusions shown in FIG. 1C. FIG. 7 is a perspective view showing an example of a method for manufacturing the coil component shown in FIG. 1A. FIG. 8 is a perspective view showing an example of a step subsequent to the step shown in FIG. 7. FIG. 9 is a perspective view showing an example of a step subsequent to the step shown in FIG. 8. FIG. 10 is a cross-sectional view of the mold shown in FIG. 9 taken along line X-X. FIG. 11 is a perspective view showing an example of a step subsequent to the step shown in FIG. 9. FIG. 12A is a perspective view showing an example of a step subsequent to the step shown in FIG. 11. FIG. 12B is a perspective view showing an example of a step subsequent to the step shown in FIG. 11. FIG. 13A is a perspective view of an example of a coil component according to a second embodiment. FIG. 13B is a perspective view of the coil component shown in FIG. 13A, viewed from the first surface side. FIG. 14 is a perspective view showing an example of a method for manufacturing the coil component shown in FIG. 13A. FIG. 15 is a perspective view showing an example of a step subsequent to the step shown in FIG. 14. Fig. 16 is a perspective view showing an example of a step subsequent to the step shown in Fig. 15. Fig. 17 is a cross-sectional view taken along line XVII-XVII of the mold shown in Fig. 16. Fig. 18 is a perspective view showing an example of a step subsequent to the step shown in Fig. 16. Fig. 19 is a perspective view showing an example of a step subsequent to the step shown in Fig. 18.Fig. 20A is a perspective view of an example of a modified example of the coil component shown in Fig. 1A. Fig. 20B is a perspective view of the coil component shown in Fig. 20A as viewed from the first surface side. Fig. 21 is a perspective view of an example of a modified example of the coil component shown in Fig. 1A. Fig. 22 is a perspective view of an example of a modified example of the coil component shown in Fig. 1A. Fig. 23 is a bottom view showing variations in the shape of the protrusions shown in (a-1) of each of Figs. 4A, 5A, and 6A.

[0013] Hereinafter, embodiments of the present disclosure will be described with reference to the drawings. Note that the contents shown in the drawings are merely schematic and illustrative for understanding the present disclosure, and the appearance and dimensional ratios may differ from the actual product. Furthermore, the present disclosure is not limited to the following embodiments.

[0014] 1A functions as, for example, an inductor and is mounted in the power supplies of various electrical devices. The coil component 1 has an element body 2, a coil 10, and terminal electrodes 40 a and 40 b. The coil component 1 is a surface-mount type coil component.

[0015] The element body 2 has a core 20 and an exterior body 30 that covers the core 20 and the coil 10. The element body 2 is a hexahedron, but may be another polyhedron such as an octahedron. The element body 2 has a first surface 30a on which the terminal electrodes 40a and 40b are arranged, a second surface 30b opposite the first surface 30a, and one or more connection surfaces that connect the first surface 30a and the second surface 30b. In this embodiment, the element body 2 is a hexahedron. Therefore, the element body 2 has a third surface 30c, a fourth surface 30d adjacent to the third surface 30c, a fifth surface 30e adjacent to the fourth surface 30d, and a sixth surface 30f adjacent to the fifth surface 30e, as connection surfaces that connect the first surface 30a and the second surface 30b.

[0016] In FIG. 1A , the X-axis corresponds to the direction in which the fourth surface 30d and the sixth surface 30f face each other. The Y-axis corresponds to the direction in which the third surface 30c and the fifth surface 30e face each other. The Z-axis is perpendicular to the X-axis and the Y-axis and corresponds to the direction in which the first surface 30a and the second surface 30b face each other. Hereinafter, for each of the X-axis, Y-axis, and Z-axis, the direction away from the center of the element body 2 is referred to as the outward direction, and the direction toward the center of the element body 2 is referred to as the inward direction. The positive side of the Z-axis (the direction from the first surface 30a to the second surface 30b) is referred to as the upper side (upward), and the negative side of the Z-axis (the direction from the second surface 30b to the first surface 30a) is referred to as the lower side (downward). However, the upper side in the Z-axis direction does not necessarily coincide with the upper side in the vertical direction. The lower side in the Z-axis direction does not necessarily coincide with the lower side in the vertical direction.

[0017] In the present disclosure, the terms "equal," "the same," "equivalent," or "similar" do not only refer to a state in which the physical quantities of multiple objects being compared are exactly equal, identical, equivalent, or similar, but also include a state in which there is an error of ±Δ% or less (not particularly limited, for example, Δ=7, 5, or 3) between the physical quantities of multiple objects being compared.

[0018] Furthermore, in the present disclosure, "parallel" does not only refer to strict parallelism, but also includes a state in which there is an error of ±Δθ° (not particularly limited, for example, Δθ=3) or less from strict parallelism. Furthermore, "perpendicular" or "orthogonal" does not only refer to strict perpendicular or perpendicular, but also includes a state in which there is an error of ±Δθ° (not particularly limited, for example, Δθ=3) or less from strict perpendicular or perpendicular.

[0019] The length of the element body 2 in the X-axis direction is not particularly limited, but is, for example, 0.6 mm to 6.5 mm. The length of the element body 2 in the Y-axis direction is not particularly limited, but is, for example, 0.6 mm to 6.5 mm. The length of the element body 2 in the Z-axis direction is not particularly limited, but is, for example, 0.5 mm to 5.0 mm.

[0020] As shown in FIG. 1C , the second surface 30b, the third surface 30c, the fourth surface 30d, the fifth surface 30e, and the sixth surface 30f are formed by the exterior body 30. On the other hand, the first surface 30a is formed by the outer end surface 22a of the core 20 and a portion of the exterior body 30 located around the outer end surface 22a, and forms the mounting surface of the element body 2. The mounting surface is the surface that faces a mounting substrate (not shown) when the coil component 1 is mounted on the mounting substrate. The element body 2 does not need to include the core 20 and may be formed only by the exterior body 30, for example. In that case, the first surface 30a does not include the outer end surface 22a of the core 20 and is formed by the exterior body 30.

[0021] The element body 2 is not limited to a polyhedron, and may be a cylindrical body such as a cylinder from the viewpoint of effective magnetic flux. In the present disclosure, a cylinder also includes a solid body in which the first surface 30 a and the second surface 30 b are not congruent, such as a truncated cone. When the element body 2 is a cylinder or a truncated cone, the element body 2 is provided with one connecting surface that connects the first surface 30 a and the second surface 30 b.

[0022] The element body 2 is formed, for example, by pouring the exterior material that constitutes the exterior body 30 into a cavity of a mold in which the core 20 is placed, and then compressing and curing the poured material. The exterior material is made of a composite material that contains magnetic particles (magnetic filler) and resin. The element body 2 can also be formed by resin molding, transfer molding, injection molding, dry molding, etc.

[0023] The particle size of the magnetic particles that make up the exterior material is not particularly limited, but is, for example, 1 μm to 50 μm. The magnetic material (magnetic filler) that makes up the exterior material is not particularly limited, but is, for example, ferrite or a metallic magnetic material. The resin that makes up the exterior material is not particularly limited, but is, for example, epoxy resin or phenol resin. The relative magnetic permeability of the exterior body 30 is not particularly limited, but is, for example, 1 to 20,000.

[0024] As shown in FIG. 1B , the third surface 30c, the fourth surface 30d, the fifth surface 30e, and the sixth surface 30f are inclined surfaces that form acute angles with the first surface 30a. The inclination angle θ1 of the third surface 30c relative to the first surface 30a is not particularly limited, but is, for example, 60°≦θ1<90°. The inclination angle θ1 may be, for example, 75°≦θ1≦85°. However, the third surface 30c does not have to be an inclined surface, and the inclination angle θ1 of the third surface 30c relative to the first surface 30a may be 90°. The same applies to the inclination angle θ2 of the fourth surface 30d relative to the first surface 30a, the inclination angle θ3 of the fifth surface 30e relative to the first surface 30a, and the inclination angle θ4 of the sixth surface 30f relative to the first surface 30a. Note that the inclination angles θ1, θ2, θ3, and θ4 may all be equal or different.

[0025] By making at least one of the third surface 30c, the fourth surface 30d, the fifth surface 30e, and the sixth surface 30f an inclined surface, it is possible to identify the orientation of the exterior body 30 from the external shape of the exterior body 30. Furthermore, by making at least one of the third surface 30c, the fourth surface 30d, the fifth surface 30e, and the sixth surface 30f an inclined surface, it is possible to reduce the size of the exterior body 30.

[0026] In the present embodiment, the third surface 30c, the fourth surface 30d, the fifth surface 30e, and the sixth surface 30f are each inclined surfaces, but any one, two, or three of these surfaces may be inclined surfaces. For example, the mutually opposing third surface 30c and the fifth surface 30e may each be inclined surfaces, while the mutually opposing fourth surface 30d and the sixth surface 30f may not be inclined surfaces. Alternatively, the mutually opposing fourth surface 30d and the sixth surface 30f may each be inclined surfaces, while the third surface 30c and the fifth surface 30e may not be inclined surfaces. Forming inclined surfaces on the exterior body 30 in this manner facilitates the mold removal process when molding the exterior body 30 using a mold.

[0027] The first ridge 35a located between the second surface 30b and the third surface 30c is formed with the unevenness 32. The second ridge 35b located between the second surface 30b and the fourth surface 30d is also formed with the unevenness 32. The third ridge 35c located between the second surface 30b and the fifth surface 30e is also formed with the unevenness 32. The fourth ridge 35d located between the second surface 30b and the sixth surface 30f is also formed with the unevenness 32.

[0028] 1B, the first ridge 35a, the second ridge 35b, the third ridge 35c, and the fourth ridge 35d each have an irregularity 32 formed thereon, and the irregularity 32 is formed around the outer periphery of the second surface 30b. However, the irregularity 32 may be formed on only one, two, or three of these ridges.

[0029] In the first ridge portion 35 a, the irregularities 32 are formed continuously or intermittently from one end to the other end of the first ridge portion 35 a in the X-axis direction. However, the irregularities 32 may be formed locally in a part of the first ridge portion 35 a (for example, the center or end in the X-axis direction). The same applies to the irregularities 32 formed in the third ridge portion 35 c.

[0030] The irregularities 32 are formed continuously or intermittently on the second ridge portion 35b from one end to the other in the Y-axis direction. However, the irregularities 32 may be formed locally on a part of the second ridge portion 35b (for example, the center or end in the Y-axis direction). The same applies to the irregularities 32 formed on the fourth ridge portion 35d.

[0031] The irregularities 32 may be formed not only on the first ridge 35a, the second ridge 35b, the third ridge 35c, and the fourth ridge 35d, but also around these ridges. For example, the irregularities 32 may also be formed on the outer edge of the second surface 30b. In this case, the irregularities 32 may be formed up to a position spaced a distance W1 (see the enlarged view in FIG. 1B ) inward from the first ridge 35a in the Y-axis direction. The distance W1 is, for example, 0.5 μm to 300 μm, or 0.5 μm to 40 μm. The irregularities 32 may also be formed up to a position spaced a distance W1 inward from the second ridge 35b in the X-axis direction. The irregularities 32 may also be formed up to a position spaced a distance W1 inward from the third ridge 35c in the Y-axis direction. Alternatively, the irregularities 32 may be formed up to a position spaced a distance the same as the distance W1 inward in the X-axis direction from the fourth ridge line portion 35d.

[0032] Alternatively, the irregularities 32 may also be formed on the upper end of each of the third surface 30c, the fourth surface 30d, the fifth surface 30e, and the sixth surface 30f. In this case, the irregularities 32 may be formed downward from the first ridge 35a by a distance W2 (see the enlarged view in FIG. 1B ). The distance W2 may be, for example, 10 μm to 300 μm, or 20 μm to 200 μm, or 50 μm to 100 μm. Note that the distance W2 may be the same as the height H3 (thickness of the connecting portion 90) of the connection region 72 shown in FIG. 10 (described later), and may be, for example, 10 μm to 50 μm, or 20 μm to 40 μm. Furthermore, the irregularities 32 may also be formed downward from the second ridge 35b in the negative Z-axis direction by a distance equal to the distance W2. Alternatively, the irregularities 32 may be formed up to a position spaced a distance W2 from the third ridge 35c in the negative Z-axis direction, or up to a position spaced a distance W2 from the fourth ridge 35d in the negative Z-axis direction.

[0033] As described below, the manufacturing method of the coil component 1 includes a step of singulating a molded body including a plurality of element bodies 2. In this step, the molded body is fractured rather than cut with a cutting tool. At this time, the resin constituting the element body 2 (exterior body 30) peels off along the magnetic particles constituting the element body 2 (exterior body 30) at the first ridge line portion 35a, the second ridge line portion 35b, the third ridge line portion 35c, and the fourth ridge line portion 35d. As a result, irregularities 32 are formed on each of the first ridge line portion 35a, the second ridge line portion 35b, the third ridge line portion 35c, and the fourth ridge line portion 35d. Therefore, at least a portion of the irregularities 32 has a shape that reflects the shape of the magnetic particles (a shape that follows the surface shape of the magnetic particles), and the irregularities 32 are different from so-called burrs. In other words, the irregularities 32 are not located outside but inside (toward the coil 10) an imaginary plane formed by extending the flat regions of each of the third surface 30c to the sixth surface 30f. In this way, the manufacturing method of the coil component 1 can separate the coil component 1 into individual pieces without generating external burrs.

[0034] A curved portion 31 is formed on the fifth ridge 35e located between the third surface 30c and the fourth surface 30d. A curved portion 31 is also formed on the sixth ridge 35f located between the fourth surface 30d and the fifth surface 30e. A curved portion 31 is also formed on the seventh ridge 35g located between the fifth surface 30e and the sixth surface 30f. A curved portion 31 is also formed on the eighth ridge 35h located between the sixth surface 30f and the third surface 30c. The curved portion 31 is curved in a cross section perpendicular to a direction perpendicular to the first surface 30a (the Z-axis direction). In the example shown in FIG. 1B , a curved portion 31 is formed on each of the fifth ridge 35e, the sixth ridge 35f, the seventh ridge 35g, and the eighth ridge 35h, but the curved portion 31 may be formed on only one, two, or three of these ridges.

[0035] In the fifth ridge portion 35e, the curved portion 31 is formed continuously or intermittently from one end to the other end in the extension direction of the fifth ridge portion 35e. However, the curved portion 31 may be formed locally in a portion of the fifth ridge portion 35e (e.g., the center or end portion in the extension direction of the fifth ridge portion 35e). The same applies to the curved portions 31 formed in the sixth ridge portion 35f, the seventh ridge portion 35g, and the eighth ridge portion 35h. Forming the curved portion 31 in at least one of the fifth ridge portion 35e, the sixth ridge portion 35f, the seventh ridge portion 35g, and the eighth ridge portion 35h prevents magnetic flux from concentrating around these ridge portions, thereby improving the inductance characteristics of the coil device 1.

[0036] The degree of curvature (radius of curvature) of the curved portion 31 may increase toward one side in the Z-axis direction. In the example shown in FIG. 1B , the radius of curvature of the curved portion 31 decreases toward the second surface 30b, but the radius of curvature of the curved portion 31 may decrease toward the first surface 30a. However, the radius of curvature of the curved portion 31 is an index representing the degree of curvature of the outer circumferential surface (planar curve) of the exterior body 30 at the position of the fifth ridge line 35e (or the sixth ridge line 35f, the seventh ridge line 35g, or the eighth ridge line 35h) in a cross section of the exterior body 30 perpendicular to the Z-axis. By increasing the radius of curvature of the curved portion 31 toward one side in the Z-axis direction in at least one of the fifth ridge portion 35e, the sixth ridge portion 35f, the seventh ridge portion 35g, and the eighth ridge portion 35h, it is possible to prevent magnetic flux from concentrating on one side in the extension direction of these ridge portions, and improve the inductance characteristics of the coil component 1.

[0037] The second surface 30b may have any desired pattern formed by a concave-convex pattern 33. The concave-convex pattern 33 is formed by a plurality of convex portions and / or a plurality of concave portions. These convex portions and / or concave portions may be regularly formed at a predetermined pitch along the X-axis and / or Y-axis. Alternatively, the concave-convex pattern 33 may be a collection of randomly arranged convex portions and / or concave portions. The heights of the plurality of convex portions forming the concave-convex pattern 33 may be uniform or may vary. The depths of the plurality of concave portions forming the concave-convex pattern 33 may be uniform or may vary. The heights of the plurality of convex portions or the depths of the plurality of concave portions forming the concave-convex pattern 33 are not particularly limited, but are, for example, 0.1 μm to 40 μm.

[0038] The uneven pattern 33 is formed from one end to the other in the X-axis direction of the second surface 30b. The uneven pattern 33 is also formed from one end to the other in the Y-axis direction of the second surface 30b. However, the uneven pattern 33 may be formed locally on the second surface 30b. The unevenness (e.g., surface roughness) of the uneven pattern 33 is smaller than the unevenness of the unevenness 32, but may be equal to or greater than the unevenness of the unevenness 32.

[0039] By forming the uneven pattern 33 on the second surface 30b, the orientation of the exterior body 30 can be identified from the external shape of the exterior body 30. The uneven pattern 33 may be formed in the shape of slits on the second surface 30b. Alternatively, the uneven pattern 33 may be formed on the first surface 30a.

[0040] As shown in FIG. 1A , the core 20 has a core portion 21 and a flange portion 22. The core 20 is a T-shaped core and is formed from a composite material containing a magnetic material and a resin. The core 20 is formed, for example, by powder compaction, injection molding, or machining. The material forming the core 20 may be the same as or different from the material forming the exterior body 30. The relative permeability of the core 20 may be the same as or different from the relative permeability of the exterior body 30. For example, the core 20 may be made of a material with a higher relative permeability than the exterior body 30.

[0041] The core 21 has a cylindrical shape and protrudes from the center of the flange 22. The axial direction of the core 21 corresponds to the Z-axis direction. The axial direction of the core 21 also corresponds to the winding axis direction of the coil 10. The core 21 may protrude from the center of the flange 22 at a position offset in the radial direction. The core 21 is located inside the outer casing 30. The shape of the core 21 may be, for example, a square prism, an octagonal prism, or any other polygonal prism.

[0042] The flange portion 22 has a flat rectangular parallelepiped shape (flat plate shape) and is formed at one axial end of the core portion 21. The flange portion 22 has an outer end surface 22a, an inner end surface 22b, and a side surface 22c. The inner end surface 22b is a surface connected to the core portion 21. The outer end surface 22a is a surface facing the inner end surface 22b. The side surface 22c is a surface connecting the outer end surface 22a and the inner end surface 22b. The flange portion 22 is arranged parallel to the second surface 30b of the exterior body 30. The planar shape of the flange portion 22 may be, for example, circular, octagonal, or another polygonal shape. Note that either the core portion 21 or the flange portion 22 may be omitted from the core 20.

[0043] As shown in FIG. 1C , the outer end surface 22a of the flange portion 22 is exposed from the first surface 30a but may be covered by the exterior body 30. A terminal electrode 40a is provided on one side of the outer end surface 22a in the X-axis direction, and a terminal electrode 40b is provided on the other side of the outer end surface 22a in the X-axis direction. As indicated by the dashed lines in FIG. 1C , the flange portion 22 has an electrode contact portion 36a located on one side of the outer end surface 22a in the X-axis direction and an electrode contact portion 36b located on the other side of the outer end surface 22a in the X-axis direction. The electrode contact portion 36a is the contact surface between the terminal electrode 40a and the first surface 30a, and the terminal electrode 40a is in contact with the electrode contact portion 36a. The electrode contact portion 36b is the contact surface between the terminal electrode 40b and the first surface 30a, and the terminal electrode 40b is in contact with the electrode contact portion 36b.

[0044] The thermal expansion coefficient of the core 20 (at least one of the flange portion 22 and the core portion 21) may be equal to or different from the thermal expansion coefficient of the exterior body 30. The thermal expansion coefficient of the core 20 (at least one of the flange portion 22 and the core portion 21) may be smaller than or larger than the thermal expansion coefficient of the exterior body 30.

[0045] When the core portion 21 is formed of an annealed metal, the thermal expansion coefficient of the core portion 21 is, for example, 10 ppm / K or more and 20 ppm / K or less. When the core portion 21 is formed of a composite material containing a magnetic material and a resin, the thermal expansion coefficient of the core portion 21 is, for example, 20 ppm / K or more and 60 ppm / K or less. The thermal expansion coefficient of the exterior body 30 is, for example, 15 ppm / K. The difference between the thermal expansion coefficient of the core portion 21 and the thermal expansion coefficient of the exterior body 30 may be, for example, 2 ppm / K or more, or 5 ppm / K or more. The difference between the thermal expansion coefficient of the core portion 21 and the thermal expansion coefficient of the exterior body 30 may be, for example, 45 ppm / K or less, or 10 ppm / K or less. In this case, it is possible to prevent cracks from occurring in the exterior body 30 around the core portion 21 due to the thermal expansion coefficient of the core portion 21.

[0046] An example of a method for making the thermal expansion coefficient of the core portion 21 smaller than the thermal expansion coefficient of the exterior body 30 is to perform an annealing treatment on the core portion 21. When the core portion 21 contains magnetic particles and a resin, the annealing treatment on the core portion 21 reduces the resin content, thereby reducing the thermal expansion coefficient of the core portion 21.

[0047] Note that the thermal expansion coefficient of the core portion 21 may be made smaller than that of the exterior body 30 by forming the core 20 from a material different from that of the exterior body 30. Alternatively, when the core 20 and the exterior body 30 both contain magnetic particles and resin, the thermal expansion coefficient of the core portion 21 may be made smaller than that of the exterior body 30 by making the blending ratio of the resin in the core 20 smaller than that of the exterior body 30. Alternatively, the thermal expansion coefficient of the core portion 21 may be made smaller than that of the exterior body 30 by forming the core 20 (core portion 21 and / or flange portion 22) from ceramics such as sintered ferrite.

[0048] As shown in FIG. 1A , the coil 10 has a winding portion 11 wound into a coil shape and lead portions 12a and 12b drawn out from the winding portion 11. The winding portion 11 is located inside the element body 2 (exterior body 30) and is provided on the outer circumferential surface of the core portion 21. The winding portion 11 is formed, for example, by winding a wire around the core portion 21. However, if the coil 10 is an air-core coil, the winding portion 11 may be fitted into the core portion 21. The wire forming the winding portion 11 can be, for example, a conductive core wire made of copper or the like, such as a rectangular wire, a round wire, a twisted wire, a Litz wire, or a braided wire, or an insulating-coated wire in which such a conductive core wire is covered with an insulating coating. Specifically, known winding wires such as AIW, UEW, PEW, and USTC can be used. The wire diameter is not particularly limited, but in the case of a round wire, it is, for example, 50 μm to 2 mm. In the case of a rectangular wire, for example, the wire thickness is 20 μm to 2 mm and the wire width is 40 μm to 2 mm. As shown in FIG. 2A, the number of layers in the winding axis direction of the winding portion 11 is, for example, three, and the number of layers in the radial direction is, for example, three.

[0049] 1A , lead-out portions 12a and 12b respectively constitute one end and the other end of the wire forming coil 10 and are spaced apart in the X-axis direction. Lead-out portion 12a is drawn out from one end of winding portion 11 in the Z-axis direction inside exterior body 30 toward third surface 30c of exterior body 30. Similarly, lead-out portion 12b is drawn out from the other end of winding portion 11 in the Z-axis direction inside exterior body 30 toward third surface 30c of exterior body 30.

[0050] As shown in FIG. 3 , terminal electrodes 40a and 40b are formed on the flange portion 22 and are spaced apart along the X-axis. Each of the terminal electrodes 40a and 40b has an exposed portion 42 and buried portions 44 and 46. The exposed portion 42 is disposed on the outer end surface 22a and extends along the Y-axis. The shape of the exposed portion 42 is not particularly limited, but may be, for example, rectangular in plan view. At least a portion of the exposed portion 42 is exposed from the first surface 30a (see FIG. 1C ). The buried portions 44 and 46 are disposed on the side surface 22c and face each other along the Y-axis. The buried portion 44 extends upward from one longitudinal end of the exposed portion 42. The buried portion 46 extends upward from the other longitudinal end of the exposed portion 42. The terminal electrode 40a is connected to the lead portion 12a, and the terminal electrode 40b is connected to the lead portion 12b. The lead portion 12a is connected to the embedded portion 44 of the terminal electrode 40a. The lead portion 12b is connected to the embedded portion 44 of the terminal electrode 40b. The terminal electrodes 40a and 40b are each composed of, for example, a laminated electrode film made of an underlying electrode film and a plating film formed on the underlying electrode film. The underlying electrode film is a conductive paste film containing, but is not limited to, a metal such as Sn, Ag, Ni, Cu, or Pd, or an alloy thereof. The plating film is also not limited to, but is, for example, a metal such as Sn, Au, Ni, Pt, Ag, Pd, or Cu, or an alloy thereof.

[0051] As shown in FIG. 2A , the thickness of the terminal electrode 40a in its cross section becomes thinner toward the outer edge of the terminal electrode 40a and becomes thicker toward the center of the terminal electrode 40a. The cross-sectional shape of the terminal electrode 40a is convex, protruding downward. The same is true for the cross-sectional shape of the terminal electrode 40b. However, the cross-sectional shapes of the terminal electrodes 40a and 40b are not limited to the shape shown in FIG. 2A . For example, the cross-sectional shapes of the terminal electrodes 40a and 40b may be rectangular.

[0052] As shown in Fig. 2B, the thickness of the terminal electrode 40a in its longitudinal cross section becomes thinner toward the outer edge of the terminal electrode 40a and becomes thicker toward the center of the terminal electrode 40a. The longitudinal cross section of the terminal electrode 40a has a convex shape that protrudes downward. The same is true for the longitudinal cross section of the terminal electrode 40b. However, the longitudinal cross sections of the terminal electrodes 40a and 40b are not limited to the shape shown in Fig. 2B. For example, the longitudinal cross sections of the terminal electrodes 40a and 40b may be rectangular.

[0053] The thickness T of each of the terminal electrodes 40a and 40b is, for example, 3 μm to 100 μm. The thickness of the terminal electrode 40a is equal to the thickness of the terminal electrode 40b, but they may be different. The lead portion 12a is connected to the terminal electrode 40a by, for example, thermocompression bonding, soldering, or a conductive adhesive. The lead portion 12b is connected to the terminal electrode 40b by, for example, thermocompression bonding, soldering, or a conductive adhesive.

[0054] As shown in FIG. 1C , the outer periphery of the exposed portion 42 of the terminal electrode 40a has a first side 41a1, a second side 41a2, a third side 41a3, and a fourth side 41a4. The third side 41a3 connects the first side 41a1 and the second side 41a2 and extends linearly (straight) along the Y-axis. However, as described below, the third side 41a3 may extend nonlinearly. The fourth side 41a4 connects the first side 41a1 and the second side 41a2 and extends linearly (straight) along the Y-axis. The first side 41a1 and the second side 41a2 extend parallel to each other along the X-axis and face each other in the extension direction of the third side 41a3 (the Y-axis direction).

[0055] The outer periphery of the exposed portion 42 of the terminal electrode 40b has a first side 41b1, a second side 41b2, a third side 41b3, and a fourth side 41b4. The third side 41b3 connects the first side 41b1 and the second side 41b2 and extends linearly (straight) along the Y-axis. However, as described below, the third side 41b3 may extend nonlinearly. The fourth side 41b4 connects the first side 41b1 and the second side 41b2 and extends linearly (straight) along the Y-axis. The first side 41b1 and the second side 41b2 extend parallel to each other along the X-axis and face each other in the extension direction of the third side 41b3 (the Y-axis direction).

[0056] The first side 41a1, the second side 41a2, and the third side 41a3 are located on the outer edge of the first surface 30a. The first side 41b1, the second side 41b2, and the third side 41b3 are located on the outer edge of the first surface 30a. Here, the outer edge of the first surface 30a includes the outer periphery of the first surface 30a and the peripheral portion of the outer periphery of the first surface 30a. The peripheral portion of the outer periphery of the first surface 30a is the region between a first position on the outer periphery of the first surface 30a and a second position spaced a predetermined distance inward from the first position in the X-axis direction or the Y-axis direction (or, if the shape of the first surface 30a is circular or elliptical, in the radial direction). Note that "inward" refers to the direction toward the center of the first surface 30a. Furthermore, the specified length is, for example, a length equivalent to 30% or less of the length of the first surface 30a in the X-axis direction or the Y-axis direction (however, if the shape of the first surface 30a is circular or elliptical, the diameter, major axis, or minor axis).

[0057] The outer edge of the first surface 30a includes a first outer edge 2b1, a second outer edge 2b2, a third outer edge 2b3, and a fourth outer edge 2b4. The first outer edge 2b1 and the second outer edge 2b2 extend linearly (straight) along the X-axis from the terminal electrode 40a to the terminal electrode 40b. The third outer edge 2b3 and the fourth outer edge 2b4 connect the first outer edge 2b1 and the second outer edge 2b2 and extend linearly (straight) along the Y-axis. However, as described below, the third outer edge 2b3 and the fourth outer edge 2b4 may extend nonlinearly. The first outer edge 2b1 and the second outer edge 2b2 extend parallel to the X-axis and face each other in the extension direction (Y-axis direction) of the third outer edge 2b3 and the fourth outer edge 2b4.

[0058] The element body 2 has a raised portion 38. The raised portion 38 is formed at least around the terminal electrode 40a and / or 40b. The raised portion 38 is raised (protrudes) relative to the electrode contact portion 36a. In particular, the raised portion 38 is raised relative to the outer edge of the electrode contact portion 36a (particularly, the portions along the first outer edge 2b1, the second outer edge 2b2, and the third outer edge 2b3 of the first surface 30a). The raised portion 38 is also raised (protrudes) relative to the electrode contact portion 36b. In particular, the raised portion 38 is raised relative to the outer edge of the electrode contact portion 36b (particularly, the portions along the first outer edge 2b1, the second outer edge 2b2, and the fourth outer edge 2b4 of the first surface 30a). The raised portion 38 has a portion (non-overlapping portion) that does not overlap with the flange portion 22 in the Z-axis direction (as viewed from the Z-axis direction), and a portion (overlapping portion) that overlaps with the flange portion 22 in the Z-axis direction (as viewed from the Z-axis direction).

[0059] Here, the outer edge of the electrode contact portion 36a includes the outer periphery of the electrode contact portion 36a and the peripheral portion of the outer periphery of the electrode contact portion 36a. The peripheral portion of the outer periphery of the electrode contact portion 36a is the region between a first position on the outer periphery of the electrode contact portion 36a and a second position spaced a predetermined length inward from the first position in the X-axis direction or the Y-axis direction (or in the radial direction if the electrode contact portion 36a is circular or elliptical). The predetermined length is, for example, a length equivalent to 30% or less of the length of the electrode contact portion 36a in the X-axis direction or the Y-axis direction (or the diameter, major axis, or minor axis if the electrode contact portion 36a is circular or elliptical). The outer edge of the electrode contact portion 36b is defined in the same manner as the outer edge of the electrode contact portion 36a.

[0060] The protrusions 38 are located below the average height of the electrode contact portions 36a. In particular, the protrusions 38 are located below the average height of the outer edge of the electrode contact portion 36a (particularly the portions along the first outer edge 2b1, the second outer edge 2b2, and the third outer edge 2b3 of the first surface 30a). The protrusions 38 are also located below the average height of the electrode contact portions 36b. In particular, the protrusions 38 are located below the average height of the outer edge of the electrode contact portion 36a (particularly the portions along the first outer edge 2b1, the second outer edge 2b2, and the fourth outer edge 2b4 of the first surface 30a). Note that the "average height" refers to the average height of the unevenness of the electrode contact portions 36a or 36b when the electrode contact portions 36a or 36b have unevenness.

[0061] The protrusion 38 is located on the outer edge of the first surface 30a. As shown in Figures 2A and 2B, the protrusion 38 protrudes downward from the height of the electrode contact portions 36a and 36b (particularly the height of the outer edges of the electrode contact portions 36a and 36b) at the outer edge of the first surface 30a (in this embodiment, the outer side of the outer end surface 22a of the flange portion 22 in the X-axis direction in Figure 2A and the outer side of the outer end surface 22a in the Y-axis direction in Figure 2B). The protrusion 38 also extends along the outer periphery of the outer end surface 22a to surround the outer end surface 22a, and is adjacent to the terminal electrodes 40a and 40b.

[0062] In the example shown in Fig. 2A, the protrusion 38 covers the outer edge of the terminal electrode 40a in the X-axis direction. Also, in the example shown in Fig. 2B, the protrusion 38 covers the outer edge of the terminal electrode 40a in the Y-axis direction. However, as shown in Figs. 1D and 2D, the protrusion 38 does not have to cover the terminal electrodes 40a and 40b. In the example shown in Figs. 1D and 2D, the protrusion 38 is adjacent to the terminal electrodes 40a and 40b without overlapping them. The protrusion 38 is in contact with the terminal electrodes 40a and 40b along the X-axis direction, but may be spaced apart from the terminal electrodes 40a and 40b.

[0063] The protrusion 38 is formed by extending a portion of the exterior body 30 at the outer edge of the first surface 30a below the height of the outer end surface 22a (the electrode contact portions 36a and 36b, particularly the outer edges of the electrode contact portions 36a and 36b). For example, during molding of the element body 2, a portion of the exterior material constituting the exterior body 30 is caused to extend from the outside of the side surface 22c of the flange portion 22 to a position below the height of the outer end surface 22a within the mold. The protrusion 38 is formed by compressing and hardening the exterior material that has extended below the height of the outer end surface 22a. As shown by the dashed-dotted line in FIG. 2C , the boundary in the Z-axis direction between the protrusion 38 and the remaining portion of the exterior body 30 (the main body portion: the portion covering at least the core 20 and the coil 10) is formed at the height of the outer end surface 22a (the height of the electrode contact portion 36a or 36b, particularly the height of the outer edges of the electrode contact portion 36a or 36b). As shown in FIG. 2A, the height Ha from the second surface 30b to the lower end of the protrusion 38 is greater than the height Hb from the second surface 30b to the electrode contact portion 36a or 36b (particularly the outer edge of the electrode contact portion 36a or 36b).

[0064] In the example shown in Fig. 2A, the protrusion 38 does not directly cover the outer edge of the outer end surface 22a. However, as shown in Fig. 2C, the protrusion 38 may directly cover at least a portion of the outer edge of the outer end surface 22a. In the example shown in Fig. 2C, a portion of the protrusion 38 is located on the outer edge of the outer end surface 22a and overlaps the outer end surface 22a.

[0065] Here, the outer edge of the outer end surface 22a of the flange portion 22 includes the outer periphery of the outer end surface 22a and the peripheral portion of the outer periphery of the outer end surface 22a. The peripheral portion of the outer periphery of the outer end surface 22a is the region between a first position on the outer periphery of the outer end surface 22a and a second position spaced a predetermined distance inward from the first position in the X-axis direction or the Y-axis direction (or in the radial direction if the outer end surface 22a is circular or elliptical). Here, "inward" refers to the direction toward the center of the outer end surface 22a. The predetermined length is, for example, a length equivalent to 30% or less of the length of the outer end surface 22a in the X-axis direction or the Y-axis direction (or the diameter, major axis, or minor axis if the outer end surface 22a is circular or elliptical).

[0066] The raised portion 38 shown in Fig. 2C is formed as follows. For example, when molding the element body 2, inside the mold, a portion of the exterior material constituting the exterior body 30 wraps around from outside the side surface 22c of the flange 22 to a position below the height position of the outer end surface 22a, and then wraps around onto the outer end surface 22a. The exterior material that has wrapped around onto the outer end surface 22a is compressed and hardened, thereby forming the raised portion 38 shown in Fig. 2C.

[0067] 2A to 2C, the raised portion 38 is in contact with the outer periphery of the outer end surface 22a along the X-axis direction or the Y-axis direction (the radial direction of the flange portion 22). However, the raised portion 38 does not necessarily have to be in contact with the outer periphery of the outer end surface 22a. For example, the raised portion 38 shown in FIGS. 2A and 2B may be located at a position spaced outward from the outer periphery of the outer end surface 22a in the X-axis direction or the Y-axis direction.

[0068] As shown in the enlarged view of FIG. 2C , the surface roughness of the protrusion 38 is greater than that of the terminal electrode 40a. The surface roughness of the protrusion 38 is also greater than that of the core 20, which in turn is greater than that of the terminal electrode 40a. In the enlarged view of FIG. 2C , for ease of understanding, only the surface of the protrusion 38 is shown as uneven, but the surface roughness of the protrusion 38 is the same as the surface roughness of the other portions of the exterior body 30. The surface unevenness of the protrusion 38 is formed, for example, by at least a portion of the magnetic particles (magnetic filler) contained in the protrusion 38 being exposed on the surface of the protrusion 38. Alternatively, the surface unevenness of the protrusion 38 is formed, for example, by the resin on the surface of the protrusion 38 undulating along the surface shape of the magnetic particles contained in the protrusion 38. On the surface of the protrusion 38, the proportion of exposed magnetic particles is greater than the proportion of exposed resin.

[0069] At least a portion of the magnetic particles (magnetic filler) contained in the raised portion 38 is exposed on the surface of the raised portion 38, so that the bondability of the surface of the raised portion 38 to the conductive bonding material is lower than the bondability of the surface of the terminal electrode 40a to the conductive bonding material. Therefore, the surface of the raised portion 38 is less susceptible to adhesion of the conductive bonding material than the surface of the terminal electrode 40a.

[0070] 2C, the raised portion 38 may contain magnetic particles (magnetic filler) having an average particle size equal to or greater than the thickness of the terminal electrode 40a. When such magnetic particles are contained in the raised portion 38, the surface roughness of the raised portion 38 tends to be greater than the surface roughness of the terminal electrodes 40a and 40b.

[0071] In the example shown in FIG. 2A , the height (average height or maximum height) Hc of the protrusion 38 from the electrode contact portion 36a is smaller than the thickness (maximum thickness) T of the terminal electrode 40a. However, the height (maximum height) Hc of the protrusion 38 from the electrode contact portion 36a may be equal to the thickness (maximum thickness) T of the terminal electrode 40a. The thickness (maximum thickness) T of the terminal electrode 40a is not particularly limited, but is 10 μm or greater. The same applies to the thickness (maximum thickness) of the terminal electrode 40b. On the other hand, the height (average height or maximum height) Hc of the protrusion 38 from the electrode contact portion 36a is greater than the thickness (average thickness or maximum thickness) of the outer edge of the terminal electrode 40a (particularly, the portions along the first outer edge 2b1, second outer edge 2b2, and third outer edge 2b3 of the first surface 30a). However, the height (average height or maximum height) Hc of the protrusion 38 from the electrode contact portion 36a may be equal to the thickness (average thickness or maximum thickness) of the outer edge of the terminal electrode 40a (particularly, the portions along the first outer edge 2b1, the second outer edge 2b2, and the third outer edge 2b3 of the first surface 30a in FIG. 1C ). The same applies to the height (average height or maximum height) of the protrusion 38 from the electrode contact portion 36b.

[0072] Here, the outer edge of the terminal electrode 40a includes the outer periphery of the terminal electrode 40a and the peripheral portion of the outer periphery of the terminal electrode 40a. The peripheral portion of the outer periphery of the terminal electrode 40a is the region between a first position on the outer periphery of the terminal electrode 40a and a second position spaced a predetermined length inward from the first position in the X-axis direction or the Y-axis direction (however, if the shape of the terminal electrode 40a is circular or elliptical, then the radial direction). The predetermined length is, for example, a length equivalent to 30% or less of the length of the terminal electrode 40a in the X-axis direction or the Y-axis direction (however, if the shape of the terminal electrode 40a is circular or elliptical, then the diameter, major axis, or minor axis). The outer edge of the terminal electrode 40b is defined in the same way as the outer edge of the terminal electrode 40a.

[0073] The height Hc of the protrusion 38 from the electrode contact portion 36a may be smaller than the thickness (maximum thickness) T of the terminal electrode 40a either entirely or locally. Also, the height Hc of the protrusion 38 from the electrode contact portion 36a may be larger than the thickness (average thickness or maximum thickness) of the outer edge of the terminal electrode 40a (particularly, portions along the first outer edge 2b1, second outer edge 2b2, and third outer edge 2b3 of the first surface 30a in FIG. 1C ) either entirely or locally.

[0074] The height Hc of the protrusion 38 from the electrode contact portion 36a does not necessarily have to be constant and may have a distribution. For example, the height Hc of the protrusion 38 from the electrode contact portion 36a may increase as it approaches the outer periphery of the first surface 30a, or may decrease as it approaches the terminal electrode 40a or 40b. Alternatively, the height Hc of the protrusion 38 from the electrode contact portion 36a may decrease as it approaches the outer periphery of the first surface 30a, or may increase as it approaches the terminal electrode 40a or 40b.

[0075] The surface of the protrusion 38 does not necessarily have to be flat, but may be an inclined surface that is inclined relative to the electrode contact portion 36 and / or 36 b. The surface of the protrusion 38 may be a convex surface that protrudes in a direction away from the electrode contact portion 36 a, either entirely or locally, or a concave surface that recesses in a direction toward the electrode contact portion 36 a. Alternatively, the surface of the protrusion 38 may be an uneven surface, either entirely or locally.

[0076] As shown in FIG. 1C , the protrusions 38 extend along the outer edge of the first surface 30a and are located at the first outer edge 2b1, the second outer edge 2b2, the third outer edge 2b3, and the fourth outer edge 2b4. However, the protrusions 38 may be located at any one, two, or three of the first outer edge 2b1, the second outer edge 2b2, the third outer edge 2b3, and the fourth outer edge 2b4. For example, the protrusions 38 may be located at the first outer edge 2b1 and / or the second outer edge 2b2 but not at the third outer edge 2b3 and / or the fourth outer edge 2b4. Alternatively, the protrusions 38 may be located at the third outer edge 2b3 and / or the fourth outer edge 2b4 but not at the first outer edge 2b1 and / or the second outer edge 2b2. Alternatively, the protrusions 38 may be located on the first outer edge 2b1 and the third outer edge 2b3, but not on the second outer edge 2b2 and the fourth outer edge 2b4. Alternatively, the protrusions 38 may be located on the second outer edge 2b2 and the fourth outer edge 2b4, but not on the first outer edge 2b1 and the third outer edge 2b3.

[0077] The raised portion 38 is formed along the X-axis over the entire first outer edge portion 2b1, but may be formed locally in a portion of the first outer edge portion 2b1 (for example, the center of the first outer edge portion 2b1 in the X-axis direction or an end portion of the first outer edge portion 2b1 in the X-axis direction). Similarly, the raised portion 38 is formed along the X-axis over the entire second outer edge portion 2b2, but may be formed locally in a portion of the second outer edge portion 2b2 (for example, the center of the second outer edge portion 2b2 in the X-axis direction or an end portion of the second outer edge portion 2b2 in the X-axis direction).

[0078] For example, the raised portion 38 may be formed only around the terminal electrode 40a and / or 40b. That is, the raised portion 38 may be formed only around the first side 41a1 of the terminal electrode 40a and / or the first side 41b1 of the terminal electrode 40b in the first outer edge portion 2b1, but not around the inter-electrode region 37 (outside the inter-electrode region 37 in the Y-axis direction). Here, "outside" refers to the direction away from the center of the first surface 30a. Furthermore, the raised portion 38 may be formed only around the second side 41a2 of the terminal electrode 40a and / or the second side 41b2 of the terminal electrode 40b in the second outer edge portion 2b2, but not around the inter-electrode region 37 (outside the inter-electrode region 37 in the Y-axis direction).

[0079] Although the protrusion 38 is formed along the Y axis over the entire third outer edge 2b3, it may be formed locally in a portion of the third outer edge 2b3 (for example, the center of the third outer edge 2b3 in the Y axis direction or an end of the third outer edge 2b3 in the Y axis direction). Similarly, the protrusion 38 is formed along the Y axis over the entire fourth outer edge 2b4, but it may be formed locally in a portion of the fourth outer edge 2b4 (for example, the center of the fourth outer edge 2b4 in the Y axis direction or an end of the fourth outer edge 2b4 in the Y axis direction).

[0080] The raised portion 38 extends continuously along the X-axis from one end to the other end of the first outer edge portion 2b1, but may be formed intermittently. Furthermore, the raised portion 38 extends continuously along the X-axis from one end to the other end of the second outer edge portion 2b2, but may be formed intermittently. The raised portion 38 does not necessarily have to extend elongatedly along the X-axis. For example, a plurality of island-shaped raised portions 38 may be discretely arranged on the first outer edge portion 2b1 and / or the second outer edge portion 2b2.

[0081] Furthermore, the raised portion 38 extends continuously along the Y axis from one end to the other end of the third outer edge portion 2b3, but may be formed intermittently. Furthermore, the raised portion 38 extends continuously along the Y axis from one end to the other end of the fourth outer edge portion 2b4, but may be formed intermittently. The raised portion 38 does not necessarily have to extend elongatedly along the Y axis. For example, a plurality of island-shaped raised portions 38 may be discretely arranged on the third outer edge portion 2b3 and / or the fourth outer edge portion 2b4.

[0082] The raised portion 38 overlaps the outer edge of the terminal electrode 40a (the peripheral portions of the first side 41a1, the second side 41a2, and the third side 41a3), and the outer edge of the terminal electrode 40a is covered by the raised portion 38. Therefore, the area of ​​the portion of the surface of the terminal electrode 40a that contributes to the adhesion of the conductive bonding material can be adjusted. Furthermore, the raised portion 38 overlaps the outer edge of the terminal electrode 40b (the peripheral portions of the first side 41b1, the second side 41b2, and the third side 41b3), and the outer edge of the terminal electrode 40b is covered by the raised portion 38. Therefore, the area of ​​the portion of the surface of the terminal electrode 40b that contributes to the adhesion of the conductive bonding material can be adjusted.

[0083] As shown in Fig. 1D, the raised portion 38 may extend along the outer periphery of the terminal electrode 40a at the outer edge of the first surface 30a without covering the terminal electrode 40a. Also, the raised portion 38 may extend along the outer periphery of the terminal electrode 40b at the outer edge of the first surface 30a without covering the terminal electrode 40b. In the example shown in Fig. 1C, the raised portion 38 is adjacent to the outer periphery of the terminal electrode 40a without overlapping it. Also, the raised portion 38 is adjacent to the outer periphery of the terminal electrode 40b without overlapping it.

[0084] In the example shown in FIG. 2E , the flange 22 has a chamfered portion 23. The chamfered portion 23 is formed on a ridge portion located between the outer end surface 22 a and the side surface 22 c. At the position of the chamfered portion 23, the outer end surface 22 a is inclined relative to the inner end surface 22 b, and the thickness of the flange 22 becomes thinner as it approaches the outer periphery of the outer end surface 22 a. Furthermore, at the position of the chamfered portion 23, the terminal electrode 40 a is inclined along the outer end surface 22 a. Therefore, the thickness of the terminal electrode 40 a becomes thinner as it approaches the outer periphery of the outer end surface 22 a. The same applies to the thickness of the terminal electrode 40 b. In this way, when the flange 22 is provided with the chamfered portion 23, a portion of the exterior material constituting the exterior body 30 is likely to extend from the outside of the side surface 22 c of the flange 22 to below the height position of the outer end surface 22 a and further onto the terminal electrode 40 a. Therefore, the raised portion 38 can indirectly cover at least a part of the chamfered portion 23 while covering the outer edge of the terminal electrode 40a.

[0085] The terminal electrodes 40a and / or 40b may not be formed on the chamfered portion 23, and the chamfered portion 23 may be exposed from the terminal electrodes 40a and / or 40b. In this case, a part of the exterior material constituting the exterior body 30 wraps around onto the chamfered portion 23 from the outside of the side surface 22c of the flange portion 22. Therefore, the raised portion 38 can directly cover at least a part of the chamfered portion 23.

[0086] As shown in FIG. 1C , the raised portion 38 extends along the first side 41 a1 of the terminal electrode 40 a at the first outer edge 2 b 1 and along the second side 41 a 2 at the second outer edge 2 b 2. However, the raised portion 38 may extend along either the first side 41 a 1 or the second side 41 a 2. In this case, the extending direction of the raised portion 38 may be inclined with respect to the first side 41 a 1 or the second side 41 a 2. Alternatively, the raised portion 38 may not be formed around the first side 41 a 1 or the second side 41 a 2. The raised portion 38 extends continuously or intermittently along the first side 41 a 1 and the second side 41 a 2.

[0087] Furthermore, the raised portion 38 extends along the first side 41b1 of the terminal electrode 40b at the first outer edge 2b1, and along the second side 41b2 at the second outer edge 2b2. However, the raised portion 38 may extend along either the first side 41b1 or the second side 41b2. In this case, the extending direction of the raised portion 38 may be inclined with respect to the first side 41b1 or the second side 41b2. Alternatively, the raised portion 38 does not have to be formed around the first side 41b1 or the second side 41b2. The raised portion 38 extends continuously or intermittently along the first side 41b1 and the second side 41b2.

[0088] The raised portion 38 extends along the third side 41a3 of the terminal electrode 40a at the fourth outer edge 2b4. The raised portion 38 also extends along the third side 41b3 of the terminal electrode 40b at the third outer edge 2b3. However, the raised portion 38 may extend along either the third side 41a3 or the third side 41b3. In this case, the extending direction of the raised portion 38 may be inclined with respect to the third side 41a3 or the third side 41b3. Alternatively, the raised portion 38 does not have to be formed around the third side 41a3 or the third side 41b3. The raised portion 38 extends continuously or intermittently along the third side 41a3 and the third side 41b3.

[0089] The raised portion 38 may extend along the first side 41a1 and / or the second side 41a2 of the terminal electrode 40a, but may not extend along the third side 41a3. Alternatively, the raised portion 38 may extend along the first side 41b1 and / or the second side 41b2 of the terminal electrode 40b, but may not extend along the third side 41b3. Alternatively, the raised portion 38 may extend along the third side 41a3 of the terminal electrode 40a, but may not extend along the first side 41a1 and / or the second side 41a2. Alternatively, the raised portion 38 may extend along the third side 41b3 of the terminal electrode 40b, but may not extend along the first side 41b1 and / or the second side 41b2.

[0090] As shown in Figures 4A to 6B, the outer end surface 22a of the flange portion 22, the terminal electrodes 40a and 40b, the first surface 30a, and the raised portion 38 can have various shapes in plan view. In Figures 4A (a-1) to (a-4), Figures 5A (a-1) to (a-4), and Figure 6A (a-1) to (a-4), the outer end surface 22a has a rectangular shape in plan view. The terminal electrodes 40a and 40b also have rectangular shapes in plan view. That is, the first side 41a1 and the second side 41a2 of the terminal electrode 40a extend parallel to each other and face each other along the extension direction of the third side 41a3. The first side 41b1 and the second side 41b2 extend parallel to each other and face each other along the extension direction of the third side 41b3. The third sides 41a3 and 41b3 extend linearly.

[0091] In (b-1) to (b-4) of FIG. 4A, (b-1) to (b-4) of FIG. 5A, and (b-1) to (b-4) of FIG. 6A, the shape of the outer end surface 22a in plan view is polygonal (for example, an octagon). The shapes of the terminal electrodes 40a and 40b in plan view are also polygonal (for example, a trapezoid). That is, the first side 41a1 and the second side 41a2 of the terminal electrode 40a are inclined with respect to the third side 41a3. The first side 41b1 and the second side 41b2 of the terminal electrode 40b are inclined with respect to the third side 41b3. The third sides 41a3 and 41b3 extend linearly.

[0092] In (c-1) to (c-4) of FIG. 4B, (c-1) to (c-4) of FIG. 5B, and (c-1) to (c-4) of FIG. 6B, the shape of the outer end surface 22a in plan view is generally rectangular (a rectangle with rounded corners) or generally elliptical. Furthermore, the shape of the terminal electrodes 40a and 40b in plan view is generally semicircular or generally semielliptical. That is, at least a portion (for example, the entirety) of the third side 41a3 is curved in an arc. Furthermore, at least a portion (for example, the entirety) of the third side 41b3 is curved in an arc. The third sides 41a3 and 41b3 extend nonlinearly.

[0093] In (d-1) to (d-4) of FIG. 4B, (d-1) to (d-4) of FIG. 5B, and (d-1) to (d-4) of FIG. 6B, the shape of the outer end surface 22a in plan view is elliptical or circular. Furthermore, the shape of the terminal electrodes 40a and 40b in plan view is semicircular or semi-elliptical. That is, the first side 41a1, the second side 41a2, and the third side 41a3 are continuous in an arc shape. Furthermore, the first side 41b1, the second side 41b2, and the third side 41b3 are continuous in an arc shape. The third side 41a3 extends nonlinearly, integral with the first side 41a1 and the second side 41a2. Furthermore, the third side 41b3 extends nonlinearly, integral with the first side 41b1 and the second side 41b2.

[0094] In (a-1) and (b-1) of FIG. 4A and (c-1) and (d-1) of FIG. 4B, the shape of the first surface 30a in plan view is rectangular. That is, the first outer edge 2b1 and the second outer edge 2b2 of the first surface 30a extend parallel to each other and face each other along the extension direction of the third outer edge 2b3 and the fourth outer edge 2b4. The raised portion 38 has a ring shape and is formed on the first outer edge 2b1, the second outer edge 2b2, the third outer edge 2b3, and the fourth outer edge 2b4 while surrounding the outer periphery of the outer end surface 22a of the flange 22. In (a-1) and (b-1) of FIG. 4A and (c-1) and (d-1) of FIG. 4B, the shape of the outer periphery of the raised portion 38 in plan view is rectangular. On the other hand, the planar shape of the inner periphery of the raised portion 38 in (a-1) of Figure 4A is rectangular, the planar shape of the inner periphery of the raised portion 38 in (b-1) of Figure 4A is polygonal (for example, octagonal), the planar shape of the inner periphery of the raised portion 38 in (c-1) of Figure 4B is approximately rectangular or approximately elliptical, and the planar shape of the inner periphery of the raised portion 38 in (d-1) of Figure 4B is elliptical.

[0095] In (a-2) and (b-2) of FIG. 4A and (c-2) and (d-2) of FIG. 4B, the shape of the first surface 30a in plan view is polygonal (for example, octagonal). That is, each of the third outer edge portion 2b3 and the fourth outer edge portion 2b4 is bent at at least one location (for example, two locations). The raised portion 38 has a ring shape and is formed on the first outer edge portion 2b1, the second outer edge portion 2b2, the third outer edge portion 2b3, and the fourth outer edge portion 2b4 while surrounding the outer periphery of the outer end face 22a. In (a-2) and (b-2) of FIG. 4A and (c-2) and (d-2) of FIG. 4B, the shape of the outer periphery of the raised portion 38 in plan view is polygonal (for example, octagonal). On the other hand, the planar shape of the inner periphery of the raised portion 38 in (a-2) of Figure 4A is rectangular, the planar shape of the inner periphery of the raised portion 38 in (b-2) of Figure 4A is polygonal (for example, octagonal), the planar shape of the inner periphery of the raised portion 38 in (c-2) of Figure 4B is approximately rectangular or approximately elliptical, and the planar shape of the inner periphery of the raised portion 38 in (d-2) of Figure 4C is elliptical.

[0096] In (a-3) and (b-3) of FIG. 4A and (c-3) and (d-3) of FIG. 4B, the planar shape of the first surface 30a is generally rectangular or elliptical. That is, the third outer edge portion 2b3 and the fourth outer edge portion 2b4 are generally curved in an arc-like shape. However, the third outer edge portion 2b3 and the fourth outer edge portion 2b4 may be partially curved in an arc-like shape. Furthermore, the first outer edge portion 2b1 and the second outer edge portion 2b2 extend parallel to each other. The raised portion 38 has a ring shape and is formed on the first outer edge portion 2b1, the second outer edge portion 2b2, the third outer edge portion 2b3, and the fourth outer edge portion 2b4, surrounding the outer periphery of the outer end surface 22a. In (a-3) and (b-3) of Fig. 4A and (c-3) and (d-3) of Fig. 4B, the outer periphery of the raised portion 38 has a substantially rectangular or elliptical shape in plan view. On the other hand, the inner periphery of the raised portion 38 in (a-3) of Fig. 4A has a rectangular shape in plan view, the inner periphery of the raised portion 38 in (b-3) of Fig. 4A has a polygonal shape (an octagon, for example) in plan view, the inner periphery of the raised portion 38 in (c-3) of Fig. 4B has a substantially rectangular or elliptical shape in plan view, and the inner periphery of the raised portion 38 in (d-3) of Fig. 4B has an elliptical shape in plan view.

[0097] In (a-4) and (b-4) of FIG. 4A and (c-4) and (d-4) of FIG. 4B, the planar shape of the first surface 30a is elliptical. That is, the first outer edge portion 2b1, the second outer edge portion 2b2, the third outer edge portion 2b3, and the fourth outer edge portion 2b4 are continuous in an elliptical shape. The first outer edge portion 2b1, the second outer edge portion 2b2, the third outer edge portion 2b3, and the fourth outer edge portion 2b4 may also be continuous in a circular shape. The raised portion 38 has a ring shape and is formed on the first outer edge portion 2b1, the second outer edge portion 2b2, the third outer edge portion 2b3, and the fourth outer edge portion 2b4 while surrounding the outer periphery of the outer end surface 22a. In (a-4) and (b-4) of Fig. 4A and (c-4) and (d-4) of Fig. 4B, the outer periphery of the raised portion 38 has an elliptical shape in plan view. On the other hand, the inner periphery of the raised portion 38 in (a-4) of Fig. 4A has a rectangular shape in plan view, the inner periphery of the raised portion 38 in (b-4) of Fig. 4A has a polygonal shape (an octagon, for example) in plan view, the inner periphery of the raised portion 38 in (c-4) of Fig. 4B has a substantially rectangular or substantially elliptical shape in plan view, and the inner periphery of the raised portion 38 in (d-4) of Fig. 4B has an elliptical shape in plan view.

[0098] As shown in Figures 5A, 5B, 6A, and 6B, the raised portion 38 does not have to be ring-shaped. In the example shown in Figures 5A and 5B, the raised portion 38 located at least on the first outer edge portion 2b1 and the raised portion 38 located at least on the second outer edge portion 2b2 face each other along the Y axis. At both ends of the flange portion 22 in the X axis direction, the side surface 22c is not covered by the exterior body 30 and is exposed to the outside. At one end of the flange portion 22 in the X axis direction, at least a portion of the third side 41a3 of the terminal electrode 40a is exposed to the outside without being adjacent to the raised portion 38. At the other end of the flange portion 22 in the X axis direction, at least a portion of the third side 41b3 of the terminal electrode 40b is exposed to the outside without being adjacent to the raised portion 38.

[0099] 6A and 6B, the raised portion 38 located at least on the third outer edge 2b3 and the raised portion 38 located at least on the fourth outer edge 2b4 face each other along the X-axis. At both ends of the flange 22 in the Y-axis direction, the side surfaces 22c are not covered by the exterior body 30 and are exposed to the outside. In (a-1) to (a-4) of FIG. 6A and (c-1) to (c-4) of FIG. 6B, at both ends of the flange 22 in the Y-axis direction, the first side 41a1 and the second side 41a2 of the terminal electrode 40a are exposed to the outside without being adjacent to the raised portion 38. In addition, the first side 41b1 and the second side 41b2 of the terminal electrode 40b are exposed to the outside without being adjacent to the raised portion 38.

[0100] 7 to 12B, a method for manufacturing the coil device 1 will be described. First, as shown in Fig. 7, a plurality of cores 20 each equipped with a plurality of coils 10 are prepared. In this embodiment, the plurality of coils 10 are fixed to the plurality of cores 20, respectively, mainly from the viewpoint of preventing misalignment of the plurality of coils 10, but the plurality of cores 20 is not essential.

[0101] The coil 10 is attached to the core 20 by fitting the winding portion 11 into the core portion 21 or by winding a wire around the core portion 21. The lead-out portion 12a of the coil 10 is connected to a terminal electrode 40a formed from the outer end surface 22a to the side surface 22c of the flange portion 22, and the lead-out portion 12b of the coil 10 is connected to a terminal electrode 40b formed from the outer end surface 22a to the side surface 22c (see FIG. 3).

[0102] The terminal electrodes 40a and 40b are formed by, but are not limited to, a paste method, a plating method, sputtering, screen printing, or the like. The terminal electrode 40a is formed on the outer end surface 22a (FIG. 2A), thereby forming the electrode contact portion 36a on the outer end surface 22a. The terminal electrode 40b is formed on the outer end surface 22a (FIG. 2A), thereby forming the electrode contact portion 36b on the outer end surface 22a.

[0103] Next, the partition 50 is prepared, and the partition 50 is attached to the base 130 via the adhesive sheet 120. For example, a double-sided adhesive sheet can be used as the adhesive sheet 120. In this case, by exposing the adhesive sheet 120 to a heated atmosphere, the partition 50 can be peeled off from the adhesive sheet 120 and separated from the base 130. However, instead of the adhesive sheet 120, an adhesive or the like may be used to adhere the partition 50 to the base 130. Alternatively, the partition 50 may be fixed to the base 130 by mechanical or magnetic means.

[0104] The partition portion 50 is made of, for example, metal, but may also be made of a heat-resistant resin or the like. The partition portion 50 has a partition wall 51 and a plurality of partition spaces 52. The partition space 52 is a bottomless cylindrical space surrounded by the partition wall 51. The plurality of partition spaces 52 are arranged in a matrix along the X-axis and Y-axis, but may also be arranged randomly. The cross-sectional shape of the partition spaces 52 perpendicular to the axial direction (Z-axis direction) corresponds to the shape of the outer end surface 22a of the flange portion 22 and is rectangular, but may also be other polygonal shapes, circular, etc. The partition portion 50 is provided with 20 partition spaces 52, but the number of partition spaces 52 is not particularly limited.

[0105] Next, the multiple cores 20 each having the multiple coils 10 are placed in the multiple partition spaces 52, respectively, so that the multiple coils 10 are placed in the multiple partition spaces 52. In this embodiment, each of the multiple coils 10 is placed in each of the multiple partition spaces 52. However, it is not necessary to place a coil 10 in all of the partition spaces 52, and it is also possible that no coil 10 is placed in any of the partition spaces 52. One axial side of the partition space 52 is closed by the adhesive sheet 120. On the other hand, the other axial side of the partition space 52 is open. Therefore, when the core 20 and the coil 10 are placed in the partition space 52, the outer end surface 22 a of the core 20 is fixed (adhered) to the adhesive sheet 120 inside the partition space 52.

[0106] Next, as shown in FIG. 8 , with the multiple cores 20 adhered to the adhesive sheet 120, the partition section 50 is placed inside a mold (lower mold) 60. Here, the mold 60 has a main body 61 and a cavity 62 formed in the main body 61. The cavity 62 is a space (recess) surrounded by an inner wall 63 and a bottom surface 64. If necessary, a release film 110 is placed on the bottom surface 64 of the cavity 62. In the example shown in FIG. 8 , the release film 110 is placed along the inner wall 63 and the bottom surface 64 of the cavity 62 so as to be in close contact with them. The outer edge of the release film 110 may be positioned outside the opening edge of the cavity 62. After the release film 110 is placed in the cavity 62, the cavity 62 is filled with an exterior material 80. A fluid material is used as the exterior material 80. The exterior material 80 is made of a composite magnetic material containing magnetic particles (magnetic filler) and a binder resin made of, for example, a thermoplastic resin or a thermosetting resin.

[0107] When the partition portion 50 is placed inside the mold 60 (cavity 62), the partition portion 50 is moved in the direction shown by the arrow in Fig. 8. This allows a plurality of cores 20 and a plurality of coils 10 to be placed in the cavity 62, as shown in Fig. 9. The mold 60 is heated before and after placing the partition portion 50 in the cavity 62. This reduces the connection strength between the adhesive sheet 120 and the partition portion 50, allowing the partition portion 50 to be detached from the base 130 shown in Fig. 8.

[0108] 10 , inside the cavity 62, the top of the core portion 21 faces the bottom surface 64 of the cavity 62 and is positioned at a distance from the bottom surface 64. In addition, the outer end surface 22a of the flange portion 22 faces the opening surface of the cavity 62. In this embodiment, the core 20 and the coil 10 are placed in the partition space 52 so that the surfaces of the terminal electrodes 40a and 40b are exposed from the partition portion 50.

[0109] The partition 50 further has a plurality of first openings 53 and a plurality of second openings 54. The first openings 53 are formed on one side of the partitioned space 52 and open toward a bottom surface 64 of the cavity 62. The second openings 54 are open on the opposite side of the first openings 53 in the Z-axis direction. The second openings 54 are formed on the other side of the partitioned space 52 and open toward the opening surface of the cavity 62. The partition 51 has a first end 51a close to the bottom surface 64 of the cavity 62 and a second end 51b opposite the first end 51a in the Z-axis direction.

[0110] When the partition portion 50 is accommodated in the cavity 62, the exterior material 80 filling the cavity 62 enters the multiple partition spaces 52. In the partition spaces 52, the winding portion 11 is covered with the exterior material 80, and the core portion 21 is also covered with the exterior material 80. At least a portion of the flange portion 22 is covered with the exterior material 80. A portion of the exterior material 80 enters the space outside the side surface 22c of the flange portion 22 in the X-axis direction and / or Y-axis direction. As shown in FIG. 10 , the exterior material 80 may enter the space outside the side surface 22c in the X-axis direction and / or Y-axis direction until it reaches at least the same height as the surfaces of the terminal electrodes 40a and 40b (particularly, the same height as the surfaces of the outer edges of the terminal electrodes 40a and 40b).

[0111] The partition 50 is accommodated inside the mold 60 so that the position of the second end 51b of the partition 51 is equal to the position of the opening surface of the cavity 62. Because the height H1 of the partition 51 is smaller than the depth H2 of the cavity 62, the first end 51a of the partition 51 is disposed at a position spaced a distance H3 from the bottom surface 64. By accommodating the partition 50 in the cavity 62, a plurality of partition areas 70 defined (partitioned) by the partition 50 (partition 51) are formed inside the cavity 62 at positions corresponding to the plurality of partition spaces 52.

[0112] The partition region 70 extends in the Z-axis direction from the opening surface of the cavity 62 to the bottom surface 64 of the cavity 62, and the height (depth) of the partition region 70 is H2. On the other hand, the partition space 52 extends in the Z-axis direction from the opening surface of the cavity 62 to a position corresponding to the first end 51a of the partition wall 51, and the height (depth) of the partition space 52 is H1. Therefore, the partition region 70 includes the partition space 52. In other words, the partition region 70 is a region formed by virtually extending the partition space 52 along the inner wall surface 51c of the partition wall 51 to the position of the bottom surface 64.

[0113] Therefore, the above-mentioned process of arranging the core 20 and the coil 10 in the partition space 52 is equivalent to the process of arranging the core 20 and the coil 10 in the partition area 70. Furthermore, the above-mentioned process of filling the partition space 52 with the outer casing material 80 is equivalent to the process of filling the partition area 70 with the outer casing material 80.

[0114] In this embodiment, as shown in Fig. 8 , the coil 10 is placed in the partition space 52, and then the partition part 50 is housed in the cavity 62, thereby placing the coil 10 in the partition area 70 shown in Fig. 10 . However, the method of placing the coil 10 in the partition area 70 is not limited to this. For example, the partition part 50 may be placed in the cavity 62, the partition area 70 may be formed in the cavity 62, and then the coil 10 may be placed in the partition area 70.

[0115] By disposing the partition portion 50 inside the cavity 62, a connection region 72 is formed inside the cavity 62 in addition to the partition region 70. The connection region 72 is a region sandwiched between the first end 51a of the partition wall 51 and the bottom surface 64 of the cavity 62. The connection region 72 has a gap formed between the first end 51a and the bottom surface 64, and connects adjacent partition regions 70 to each other. The height H3 of the connection region 72 (gap height) is, for example, 10 μm≦H3≦50 μm, or 20 μm≦H3≦40 μm.

[0116] Adjacent partition regions 70 are connected to each other via a connection region 72. The connection region 72 extends along the bottom surface 64 and connects the end of one adjacent partition region 70 (partition space 52) in the Z-axis direction to the end of the other adjacent partition region 70 (partition space 52) in the Z-axis direction. Therefore, the exterior material 80 is filled not only in the partition regions 70 but also in at least a portion of the connection region 72 that connects adjacent partition regions 70 to each other. The exterior material 80 may be filled in the connection region 72 without any gaps, or may be filled so that gaps remain. Although detailed illustration is omitted, the release film 110 shown in FIG. 8 is arranged via the connection region 72 so as to span the multiple partition regions 70 shown in FIG. 10.

[0117] The inner wall surface 51c of the partition wall 51 is an inclined surface inclined with respect to the bottom surface 64 of the mold 60 and with respect to the axial direction (Z-axis direction) of the partitioned space 52. The inclination angle θ5 of the inner wall surface 51c with respect to the first end 51a of the partition wall 51 (similar to the inclination angle of the inner wall surface 51c with respect to the bottom surface 64 of the mold 60) corresponds to the inclination angle θ1 of the third surface 30c with respect to the first surface 30a of the exterior body 30 shown in FIG. 1A . However, the inner wall surface 51c does not have to be an inclined surface, and the inclination angle θ5 of the inner wall surface 51c with respect to the bottom surface 64 of the mold 60 may be 90°. In the direction perpendicular to the axial direction of the partitioned space 52 shown in FIG. 10 (X-axis direction), the distance L between the opposing inner wall surfaces 51c increases with increasing distance from the bottom surface 64 of the cavity 62 (toward the opening surface of the cavity 62). 1A , the distance L corresponds to the length in the X-axis direction of the exterior body 30. The minimum value of the distance L may be smaller than the length in the X-axis direction of the outer end surface 22 a of the flange portion 22 (however, if the outer end surface 22 a is circular, the diameter of the outer end surface 22 a).

[0118] The cross-sectional area of ​​the partition space 52 perpendicular to the axial direction increases in a direction away from the bottom surface 64 of the cavity 62 (toward the opening surface of the cavity 62). The cross-sectional area corresponds to the cross-sectional area of ​​the exterior body 30 shown in Figure 1A in a cross section perpendicular to the Z axis. The opening area of ​​the second opening 54 is larger than the opening area of ​​the first opening 53.

[0119] Next, the exterior material 80 filled in the cavity 62 shown in FIG. 10 is compressed and cured. More specifically, an upper mold (not shown) is prepared, and the exterior material 80 is compressed and cured using the mold (lower mold) 60 and the upper mold at a predetermined mold temperature for a predetermined time. As a result, the exterior material 80 filled in the partition regions 70 is compressed and cured, and an exterior body 30 is formed inside the partition regions 70. Furthermore, the exterior material 80 filled in the connection regions 72 is compressed and cured, and a connecting portion 90 is formed inside the connection regions 72. As described above, the multiple partition regions 70 are connected via the connecting regions 72, and therefore the multiple exterior bodies 30 are connected via the connecting portion 90. In this way, in this embodiment, a molded body 100 can be formed that has multiple exterior bodies 30 formed in the multiple partition regions 70 and connecting portions 90 formed in the connection regions 72 and connected to the multiple exterior bodies 30. In another embodiment, the filling of the partition area 70 with the sheath material 80 and the compression and hardening of the sheath material 80 may proceed simultaneously.

[0120] Next, as shown in FIG. 11 , the partition section 50 with the formed molded body 100 is removed from the mold die 60 (cavity 62). Then, the multiple exterior bodies 30 are removed from the partition section 50 while being broken from the connecting portions 90. For example, a jig may be used to press the connecting portions 90 against the first end 51 a of the partition wall 51 in a direction from the first end 51 a toward the second end 51 b, thereby breaking the multiple exterior bodies 30 from the connecting portions 90. As described above, the opening area of ​​the second opening 54 is larger than the opening area of ​​the first opening 53. Therefore, the exterior bodies 30 can be easily removed from the partition region 70 through the second opening 54. Alternatively, the connecting portions 90 may be pressed against the opening edge of the first opening 54 to break the exterior bodies 30 from the connecting portions 90. Alternatively, a cutting tool may be used to cut the exterior bodies 30 from the connecting portions 90.

[0121] By breaking the multiple exterior bodies 30 at the connecting portions 90, the multiple exterior bodies 30 (element bodies 2) connected to the connecting portions 90 are separated into individual pieces, thereby obtaining the multiple individual pieces of the exterior bodies 30 as shown in FIG. 12A . In the exterior body 30, fracture surfaces having, for example, an uneven shape are formed at the locations where the connecting portions 90 were connected. These fracture surfaces correspond to the unevenness 32 formed on each of the first ridge portion 35 a, the second ridge portion 35 b, the third ridge portion 35 c, and the fourth ridge portion 35 d of the exterior body 30 shown in FIG. 1B . These fracture surfaces may extend to the second surface 30 b, the third surface 30 c, the fourth surface 30 d, the fifth surface 30 e, and the sixth surface 30 f of the exterior body 30. When the exterior body 30 is broken at the connecting portions 90, the resin peels off along the magnetic particles, so the magnetic particles are not cut and no new surfaces are generated. This makes it possible to prevent oxidation of the magnetic particles, and to suppress rust on the surface of the outer casing 30 without using a rust inhibitor. Furthermore, as a result of suppressing deterioration of the outer casing 30 due to rust, it is possible to prevent a decrease in the soft magnetic properties of the coil component 1.

[0122] In Fig. 10 , the exterior material 80 that has wrapped around into the space outside the side surface 22c of the flange 22 in the X-axis direction and / or Y-axis direction (the space between the side surface 22c and the inner wall surface 51c of the partition wall 51) becomes the raised portion 38 shown in Fig. 2A after being compressed and hardened. Here, if the formation positions of the terminal electrodes 40a and 40b (electrode contact portions 36a and 36b) are changed from the positions shown in Fig. 2A to the positions shown in Fig. 2C , the exterior material 80 that has wrapped around into the space outside the side surface 22c of the flange 22 in the X-axis direction or Y-axis direction (the space between the side surface 22c and the inner wall surface 51c of the partition wall 51) wraps around the outer edge of the outer end surface 22a of the flange 22. By compressing and hardening the exterior material 80 in this state, the raised portion 38 can also be formed on the outer edge of the outer end surface 22a, as shown in Fig. 2C . In this way, the size, shape, formation range, etc. of the raised portion 38 can be adjusted depending on conditions such as the position of the terminal electrodes 40a and 40b, the pressure when the outer casing material 80 is compressed, the type of magnetic particles and resin that make up the outer casing material 80, the size of the partition space 52, and the arrangement of the core 20 within the partition space 52.

[0123] When a matte pattern is formed on the surface of the release film 110 (Figure 8), the matte pattern can be transferred to the second surface 30b of the outer casing 30 shown in Figure 1B, thereby forming a concave-convex pattern 33 on the second surface 30b.

[0124] The thickness of the connecting portion 90 shown in Fig. 11 (corresponding to the height H3 of the connection region 72 shown in Fig. 10) is relatively thin, for example, 10 µm to 50 µm (or 20 µm to 40 µm), so that the multiple outer casings 30 can be easily broken from the connecting portion 90. As shown in Fig. 12B, when the multiple outer casings 30 are broken from the connecting portion 90, a runner of the connecting portion 90 having multiple holes formed therein is formed. In this manner, the coil component 1 can be obtained.

[0125] 1C , in the coil component 1 of this embodiment, the element body 2 has a protruding portion 38 formed at least around the terminal electrode 40 a and protruding relative to the electrode contact portion 36 a. Therefore, when the terminal electrode 40 a is bonded to a conductive pattern (not shown) of a mounting substrate with a conductive bonding material, the protruding portion 38 serves to prevent the conductive bonding material from flowing out of the terminal electrode 40 a around the terminal electrode 40 a. The protruding portion 38 also serves to prevent the conductive bonding material from flowing into the terminal electrode 40 a around the terminal electrode 40 a.

[0126] In particular, in this embodiment, the raised portion 38 is located at the outer edge of the first surface 30a. Therefore, the raised portion 38 prevents the conductive bonding material from flowing out from the terminal electrode 40a to the outside of the outer edge of the first surface 30a at the outer edge of the first surface 30a. This makes it difficult for the conductive bonding material to flow from one coil component 1 to the other coil component 1 between adjacent coil components 1, thereby preventing the occurrence of short circuits. Furthermore, the raised portion 38 prevents the conductive bonding material from flowing from the outside of the outer edge of the first surface 30a to the terminal electrode 40a at the outer edge of the first surface 30a. This makes it difficult for the conductive bonding material to flow from one coil component 1 to the other coil component 1 between adjacent coil components 1, thereby preventing the occurrence of short circuits.

[0127] Furthermore, the conductive bonding material is less likely to flow in and out between the coil component 1 and the adjacent conductive pattern, making it possible to prevent short circuits from occurring.

[0128] Furthermore, a protrusion 38 containing magnetic particles and resin is formed at the outer edge of the first surface 30a, thereby increasing the volume of the element body 2. This improves the inductance characteristics of the coil component 1 and also enhances the shielding effect against external magnetic fields.

[0129] 2C , the surface roughness of the raised portion 38 is greater than the surface roughness of the terminal electrode 40a. Therefore, due to the unevenness of the surface of the raised portion 38, the conductive bonding material is less likely to adhere to the surface of the raised portion 38 than to the surface of the terminal electrode 40a. As a result, the raised portion 38 can effectively prevent the conductive bonding material from flowing out of the terminal electrode 40a and can also effectively prevent the conductive bonding material from flowing into the terminal electrode 40a.

[0130] Furthermore, the surface of the raised portion 38 has lower adhesiveness to the conductive bonding material than the surface of the terminal electrode 40a. Here, adhesiveness to the conductive bonding material refers to solder wettability, for example, when the terminal electrode 40a is connected to a mounting substrate by solder. In this case, the conductive bonding material is less likely to adhere to the surface of the raised portion 38 than to the surface of the terminal electrode 40a, and is more likely to remain on the surface of the terminal electrode 40a. Therefore, the conductive bonding material is less likely to flow over the surface of the raised portion 38, and the raised portion 38 can effectively prevent the conductive bonding material from flowing out of the terminal electrode 40a. Furthermore, the raised portion 38 can effectively prevent the conductive bonding material from flowing into the terminal electrode 40a.

[0131] Furthermore, the height of the protrusion 38 from the electrode contact portion 36a is equal to or greater than the thickness of the outer edge of the terminal electrode 40a. Therefore, the protrusion 38 serves as a stopper against the conductive bonding material that attempts to flow out of the terminal electrode 40a or into the terminal electrode 40b. This makes it difficult for the conductive bonding material to climb over the protrusion 38, and the protrusion 38 can effectively prevent the conductive bonding material from flowing out of the terminal electrode 40a. The protrusion 38 can also effectively prevent the conductive bonding material from flowing into the terminal electrode 40b.

[0132] Furthermore, the raised portion 38 contains magnetic particles having an average particle size equal to or greater than the thickness of the outer edge of the terminal electrode 40a. Therefore, the magnetic particles having an average particle size equal to or greater than the thickness of the terminal electrode 40a can increase the height of the raised portion 38 from the electrode contact portion 36a. This makes it easier for the raised portion 38 to block the conductive bonding material attempting to flow out of or into the terminal electrode 40a. Therefore, it becomes even more difficult for the conductive bonding material to climb over the raised portion 38, and the raised portion 38 can effectively prevent the conductive bonding material from flowing out of the terminal electrode 40a. Furthermore, the raised portion 38 can effectively prevent the conductive bonding material from flowing into the terminal electrode 40b.

[0133] 1C , the raised portion 38 extends along the outer periphery of the terminal electrode 40a so as to overlap the outer edge of the terminal electrode 40a. Therefore, the raised portion 38 prevents the conductive bonding material from flowing out of the terminal electrode 40a and from flowing into the terminal electrode 40a in the vicinity of the terminal electrode 40a. The raised portion 38 also prevents the conductive bonding material from flowing out of the terminal electrode 40a and from flowing into the terminal electrode 40a in the region along the outer periphery of the terminal electrode 40a. This allows the raised portion 38 to effectively prevent the conductive bonding material from flowing out of the terminal electrode 40a and from flowing into the terminal electrode 40a.

[0134] The outer periphery of the terminal electrode 40a has a first side 41a1, a second side 41a2, and a third side 41a3 located at the outer edge of the first surface 30a. The third side 41a3 connects the first side 41a1 and the second side 41a2 and extends linearly or nonlinearly. The raised portion 38 extends along at least one of the first side 41a1 and the second side 41a2 (in this embodiment, both sides). Therefore, the raised portion 38 prevents the conductive bonding material from flowing out of the terminal electrode 40a and into the terminal electrode 40a in the regions along the first side 41a1 and the second side 41a2. For example, when the first side 41a1 of the terminal electrode 40a of one coil component 1 and the second side 41a2 of the terminal electrode 40a of the other coil component 1 are adjacent to each other via a raised portion 38 on a mounting board, it is possible to effectively prevent short circuit defects caused by the flow of conductive bonding material between these coil components 1.

[0135] Furthermore, the raised portion 38 extends along at least one of the first side 41 a 1 and the second side 41 a 2 (both in this embodiment) and the third side 41 a 3. Therefore, the raised portion 38 prevents the conductive bonding material from flowing out of the terminal electrode 40 a and prevents the conductive bonding material from flowing into the terminal electrode 40 b in the areas along the first side 41 a 1, the second side 41 a 2, and the third side 41 a 3. For example, when the first side 41 a 1 of the terminal electrode 40 a of the first coil component 1 and the second side 41 a 2 of the terminal electrode 40 a of the second coil component 1 are adjacent to each other on the mounting board via the raised portion 38, the occurrence of short circuit defects caused by the flow of conductive bonding material between these coil components 1 can be effectively prevented. Furthermore, when the third side 41a3 of the terminal electrode 40a of the first coil component 1 and the third side 41b3 of the terminal electrode 40b of the third coil component 1 are adjacent to each other via the raised portion 38 on the mounting board, it is possible to effectively prevent short circuit defects caused by the flow of conductive bonding material between these coil components 1.

[0136] Furthermore, the raised portion 38 extends along the third side 41 a3. Therefore, the raised portion 38 prevents the conductive bonding material from flowing out of the terminal electrode 40 a and prevents the conductive bonding material from flowing into the terminal electrode 40 a in the region along the third side 41 a3 of the terminal electrode 40 a. For example, when the third side 41 a3 of the terminal electrode 40 a of one coil component 1 and the third side 41 b3 of the terminal electrode 40 b of the other coil component 1 are adjacent to each other on the mounting board via the raised portion 38, it is possible to effectively prevent short circuits between these coil components 1 due to the flow of conductive bonding material.

[0137] The first side 41a1 and the second side 41a2 extend parallel to each other and face each other along the extension direction of the third side 41a3. Therefore, the protrusion 38 can be formed on the outer edge of the first surface 30a, for example, along the periphery of the rectangular terminal electrode 40a.

[0138] 4A, the first side 41a1 and the second side 41a2 are inclined with respect to the third side 41a3. Therefore, the protrusion 38 can be formed on the outer edge of the first surface 30a, for example, along the outer periphery of the polygonal terminal electrode 40a.

[0139] 4B, at least a portion (in this embodiment, the entire portion) of the third side 41a3 is curved in an arc shape. Also, for example, in (d-1) to (d-4) of FIG. 4B, the first side 41a1, the second side 41a2, and the third side 41a3 are continuous in an arc shape. Therefore, the protrusion 38 can be formed on the outer edge of the first surface 30a along the outer periphery of the curved terminal electrode 40a.

[0140] 1C , the outer edge of the first surface 30a includes a first outer edge 2b1 and a second outer edge 2b2 extending from the terminal electrode 40a toward the terminal electrode 40b, and a third outer edge 2b3 and a fourth outer edge 2b4 connecting the first outer edge 2b1 and the second outer edge 2b2 and extending linearly or nonlinearly. The raised portion 38 is located on at least one of the first outer edge 2b1 and the second outer edge 2b2 (in this embodiment, both). Therefore, the raised portion 38 prevents the conductive bonding material from flowing out of the terminal electrode 40a and into the terminal electrode 40a at the first outer edge 2b1 and the second outer edge 2b2. For example, when the first outer edge portion 2b1 of one coil component 1 and the second outer edge portion 2b2 of the other coil component 1 are adjacent to each other via a raised portion 38 on a mounting board, it is possible to effectively prevent short circuit defects caused by the flow of conductive bonding material between these coil components 1.

[0141] The raised portions 38 are located on at least one of the first outer edge 2b1 and the second outer edge 2b2 (both in this embodiment) and at least one of the third outer edge 2b3 and the fourth outer edge 2b4 (both in this embodiment). Therefore, the raised portions 38 prevent the conductive bonding material from flowing out of the terminal electrode 40a and from flowing into the terminal electrode 40a at the first outer edge 2b1 and the second outer edge 2b2. Additionally, the raised portions 38 prevent the conductive bonding material from flowing out of the terminal electrode 40a and from flowing into the terminal electrode 40a at the third outer edge 2b3 and the fourth outer edge 2b4. For example, when the first outer edge 2b1 of the first coil component 1 and the second outer edge 2b2 of the second coil component 1 are adjacent to each other on the mounting board with the protrusion 38 interposed therebetween, it is possible to effectively prevent short-circuit defects caused by the flow of conductive bonding material between these coil components 1. Furthermore, when the third outer edge 2b3 of the first coil component 1 and the fourth outer edge 2b4 of the third coil component 1 are adjacent to each other on the mounting board with the protrusion 38 interposed therebetween, it is possible to effectively prevent short-circuit defects caused by the flow of conductive bonding material between these coil components 1.

[0142] Furthermore, the raised portion 38 is located on at least one of the third outer edge 2b3 and the fourth outer edge 2b4 (in this embodiment, both). Therefore, the raised portion 38 prevents the conductive bonding material from flowing out of the terminal electrode 40a and into the terminal electrode 40a at the third outer edge 2b3 and the fourth outer edge 2b4. For example, when the third outer edge 2b3 of one coil component 1 and the fourth outer edge 2b4 of the other coil component 1 are adjacent to each other on the mounting board via the raised portion 38, the occurrence of short circuits between these coil components 1 due to the flow of conductive bonding material can be effectively prevented.

[0143] The first outer edge 2b1 and the second outer edge 2b2 extend parallel to each other and face each other along the extension direction of the third outer edge 2b3 and the fourth outer edge 2b4. Therefore, for example, protrusions can be formed on the first outer edge 2b1 and the second outer edge 2b2 of the rectangular first surface 30a.

[0144] 4A (a-2) and (b-2) and FIG. 4B (c-2) and (d-2), each of the third outer edge 2b3 and the fourth outer edge 2b4 is bent at least in one place. In this case, for example, a protrusion 38 can be formed on the third outer edge 2b3 and the fourth outer edge 2b4 of the polygonal first surface 30a.

[0145] Also, for example, in (a-3) and (b-3) of FIG. 4A and (c-3) and (d-3) of FIG. 4B, at least a portion (in this embodiment, the entirety) of the third outer edge portion 2b3 and at least a portion (in this embodiment, the entirety) of the fourth outer edge portion 2b4 are curved in an arc-like shape. Also, for example, in (a-4) and (b-4) of FIG. 4A and (c-4) and (d-4) of FIG. 4B, the first outer edge portion 2b1, the second outer edge portion 2b2, the third outer edge portion 2b3, and the fourth outer edge portion 2b4 are continuous in a circular or elliptical shape. Therefore, protrusions 38 can be formed on the first outer edge portion 2b1, the second outer edge portion 2b2, the third outer edge portion 2b3, and the fourth outer edge portion 2b4 of the curved first surface 30a.

[0146] As shown in FIG. 2A , the element body 2 includes a core 20 having a core portion 21 in which the coil 10 is disposed and a flange portion 22 formed at one axial end of the core portion 21, and an exterior body 30 covering the core 20 and the coil 10 and having a raised portion 38. The flange portion 22 has an inner end surface 22b connected to the core portion 21 and an outer end surface 22a facing the inner end surface 22b. The outer end surface 22a has an electrode contact portion 36a with which the terminal electrode 40a comes into contact, and the raised portion 38 contacts the outer periphery of the outer end surface 22a along the radial direction of the flange portion 22. By configuring the element body 2 with the core 20 and the exterior body 30, the inductance characteristics of the coil component 1 can be adjusted depending on the type of magnetic material constituting the core 20 and the exterior body 30. Furthermore, the coil 10 can be fixed to the core portion 21, making it less likely for the coil 10 to become misaligned. Furthermore, since the raised portion 38 contacts the outer periphery of the outer end surface 22a of the flange portion 22, the raised portion 38 can prevent the conductive bonding material from flowing out of the terminal electrode 40a near the outer periphery of the outer end surface 22a, and can also prevent the conductive bonding material from flowing into the terminal electrode 40a.

[0147] 2C , the raised portion 38 is located on the outer edge of the outer end surface 22a of the flange portion 22. Therefore, the raised portion 38 serves as a stopper (a retainer) that fixes the core 20 to the exterior body 30. This increases the fixing strength between the core 20 and the exterior body 30, making it difficult for the core 20 to peel off from the exterior body 30.

[0148] 2E , the flange 22 has a side surface 22c connecting the outer end surface 22a and the inner end surface 22b, and a chamfered portion 23 formed on a ridge located between the outer end surface 22a and the side surface 22c. The raised portion 38 directly or indirectly covers at least a portion of the chamfered portion 23 (in this embodiment, this is the entire chamfered portion 23, but it may be a portion of the chamfered portion 23). The formation of the chamfered portion 23 on the flange 22 makes it easier for the exterior material constituting the exterior body 30 to flow around the outer end surface 22a through the chamfered portion 23 during molding of the element body 2. This makes it easier to form the raised portion 38 around the terminal electrode 40a.

[0149] 13A has the same configuration as the coil component 1 of the first embodiment, except for the following points: The same reference numerals are used to designate the same components as those of the coil component 1 of the first embodiment, and detailed descriptions thereof will be omitted.

[0150] 13A and 13B , coil device 1A includes an element body 2A, which includes an outer casing 30A. In outer casing 30A, asperities 32 are formed on ninth ridge portion 35i, tenth ridge portion 35j, eleventh ridge portion 35k, and twelfth ridge portion 35l. However, ninth ridge portion 35i is located between first surface 30a and third surface 30c, tenth ridge portion 35j is located between first surface 30a and fourth surface 30d, eleventh ridge portion 35j is located between first surface 30a and fifth surface 30e, and twelfth ridge portion 35l is located between first surface 30a and sixth surface 30f of outer casing 30A. The ninth ridge 35i, the tenth ridge 35j, the eleventh ridge 35k, and the twelfth ridge 35l form the outer periphery of the first surface 30a. In this embodiment, a protrusion 38 having irregularities 32 is formed on the outer edge of the first surface 30a.

[0151] The terminal electrodes 40aA and 40bA differ from the terminal electrodes 40a and 40b of the first embodiment in that they do not have embedded portions 44 and 46 ( FIG. 3 ). The lead portions 12a and 12b are led out from the winding portion 11 toward the outer end surface 22a. The exposed portion 42 of the terminal electrode 40aA is disposed on the outer end surface 22a so as to cover the lead portion 12a. The exposed portion 42 of the terminal electrode 40bA is disposed on the outer end surface 22a so as to cover the lead portion 12b. In this embodiment as well, the terminal electrodes 40a and 40b of the first embodiment may be provided in the coil device 1 instead of the terminal electrodes 40aA and 40bA.

[0152] Next, a method for manufacturing the coil component 1A shown in Figures 13A and 13B will be described with reference to Figures 14 to 19. First, as shown in Figure 14, a plurality of cores 20 each having a plurality of coils 10 are prepared. Next, the outer end surface 22a of the flange portion 22 is adhered to a base 130 via an adhesive sheet 120.

[0153] Next, as shown in FIG. 15 , the base 130 to which the multiple cores 20 are adhered is moved in the direction of the arrow in the figure toward a mold (lower mold) 60A filled with an outer jacket material 80. Then, as shown in FIG. 16 , the multiple coils 10 ( FIG. 15 ) and the multiple cores 20 are housed inside the mold 60A. Here, as shown in FIG. 15 , the mold 60A has a main body 61, a cavity 62, and a partition wall 66. The cavity 62 is partitioned by the partition wall 66, and multiple partition spaces 65 are formed inside the cavity 62. The partition space 65 is a cylindrical space with a bottom surrounded by the partition wall 66.

[0154] A release film 110 is disposed on the bottom surface 64 of the cavity 62. The release film 110 is disposed so as to be in close contact with the inner wall 63, the bottom surface 64, and the partition wall 66 of the cavity 62. The exterior material 80 is filled into the cavity 62 with the release film 110 disposed in the cavity 62.

[0155] 16 , the mold 60A is heated before and after the core 20 is placed in the cavity 62. This reduces the connection strength between the adhesive sheet 120 and the outer end surface 22 a of the flange portion 22, allowing the core 20 to be detached from the base 130.

[0156] 17 , when the core 20 is accommodated in the cavity 62, the winding portion 11 is covered with the exterior material 80 in the partition space 65, and the core portion 21 is also covered with the exterior material 80. Furthermore, at least a portion of the flange portion 22 is covered with the exterior material 80. A portion of the exterior material 80 enters the space outside the side surface 22 c of the flange portion 22 in the X-axis direction and / or Y-axis direction (the space between the side surface 22 c of the flange portion 22 and the inner wall surface 66 a of the partition wall 66). The exterior material 80 may enter the space outside the side surface 22 c in the X-axis direction and / or Y-axis direction (the space between the side surface 22 c of the flange portion 22 and the inner wall surface 66 a of the partition wall 66) until it reaches at least the same height as the surfaces of the terminal electrodes 40 aA and 40 bA (particularly, the same height as the surfaces of the outer edges of the terminal electrodes 40 aA and 40 bA).

[0157] A connection region 67 is formed at the upper end 66b of the partition wall 66. The exterior material 80 filled in the cavity 62 can flow from one adjacent partition space 65 to the other adjacent partition space 65 through the connection region 67. The upper end 66b of the partition wall 66 is covered by the exterior material 80 filled in the connection region 67.

[0158] The inner wall surface 66a of the partition wall 66 is an inclined surface that is inclined with respect to the bottom surface 64 of the mold 60A. In a direction perpendicular to the axial direction of the partition space 65 (the X-axis direction), the distance L between the opposing inner wall surfaces 66a increases as the distance increases from the bottom surface 64 of the cavity 62 (toward the opening surface of the cavity 62). In addition, the cross-sectional area perpendicular to the axial direction of the partition space 65 increases as the distance increases from the bottom surface 64 of the cavity 62 (toward the opening surface of the cavity 62).

[0159] Next, the exterior material 80 filled in the cavity 62 is compressed and hardened. As a result, the exterior material 80 filled in the partition space 65 is compressed and hardened, and an exterior body 30A is formed inside the partition space 65. Furthermore, the exterior material 80 filled in the connection region 67 is compressed and hardened, and a linking portion 90A is formed in the connection region 67. As described above, the multiple partition spaces 65 are connected via the connection region 67, and therefore the multiple exterior bodies 30A are connected via the linking portion 90A. In this way, also in this embodiment, it is possible to form a molded body 100A having multiple exterior bodies 30A formed in the multiple partition spaces 65 and linking portions 90A formed in the connection region 67 and connected to the multiple exterior bodies 30A.

[0160] Next, as shown in FIG. 18 , the molded body 100A is removed from the mold 60A (cavity 62). Next, for example, using a jig, the multiple exterior bodies 30A (element bodies 2A) are broken at the connecting portions 90A. By breaking the multiple exterior bodies 30A at the connecting portions 90A, the multiple exterior bodies 30A connected via the connecting portions 90A are separated into individual pieces, and multiple pieces of the exterior bodies 30A (element bodies 2A) as shown in FIG. 19 can be obtained. In the exterior bodies 30A, fracture surfaces having, for example, an uneven shape are formed at the portions where the connecting portions 90A were connected. These fracture surfaces are the unevenness 32 formed on each of the ninth ridge portion 35i, the tenth ridge portion 35j, the eleventh ridge portion 35k, and the twelfth ridge portion 35l of the exterior body 30A shown in FIG. 13B . This fracture surface may extend to the first surface 30 a, the third surface 30 c, the fourth surface 30 d, the fifth surface 30 e, and the sixth surface 30 f of the exterior body 30.

[0161] 17, the exterior material 80 that has wrapped around the space outside the side surface 22c of the flange 22 in the X-axis direction and / or Y-axis direction (the space between the side surface 22c of the flange 22 and the inner wall surface 66a of the partition wall 66) becomes the raised portion 38 shown in FIG. 13B after being compressed and hardened. When the exterior body 30A is broken from the connecting portion 90A, at least a portion of the outer periphery of the raised portion 38 is broken. Therefore, as shown in FIG. 13B, the outer periphery of the raised portion 38 has an irregularity 32 formed thereon. In this manner, the coil device 1 can be obtained.

[0162] In this embodiment, the same effects as in the first embodiment can be obtained. In addition, in this embodiment, the partitions 50 ( FIG. 7 ) are not required in the manufacturing process of the coil component 1A. Therefore, there is no need to consider the accuracy of aligning the partitions 50 with the base 130 ( FIG. 7 ), and the manufacturing of the coil component 1A is easy.

[0163] The present disclosure is not limited to the above-described embodiments, and various modifications can be made within the scope of the present disclosure.

[0164] In each of the above embodiments, as shown in FIG. 3, the core 20 is a T-core, but it may be a drum core in which flanges 22 are formed on both axial ends of the core portion 21.

[0165] In each of the above embodiments, as shown in Fig. 20A, the coil 10 may be made of a rectangular wire. The coil 10 is an edgewise wound rectangular wire, but may also be a flatwise wound rectangular wire. As shown in Fig. 20B, a portion of the lead-out portion 12a of the coil 10 is exposed from the first surface 30a. Similarly, a portion of the lead-out portion 12b of the coil 10 is exposed from the first surface 30a. The portion of the lead-out portion 12a exposed from the first surface 30a and the portion of the lead-out portion 12b exposed from the first surface 30a function as terminal electrodes.

[0166] 20A and 20B, the terminal electrodes 40a and 40b (FIG. 1A) can be omitted, thereby simplifying the configuration and manufacturing process of the coil component 1. Furthermore, because the coil 10 is formed from a rectangular wire, it is possible to prevent the coil 10 from shifting position inside the element body 2 without fixing the coil 10 to the core 20. Furthermore, it is possible to increase the value of the current flowing through the coil 10.

[0167] In each of the above embodiments, the winding axis direction of winding unit 11 may be parallel to first surface 30a, as shown in Fig. 21 . In Fig. 21 , the winding axis direction of winding unit 11 corresponds to the Y-axis direction. The shape of winding unit 11 as viewed from the winding axis direction is a rectangle with its long side in the X-axis direction, but it may also be a square, another polygon, a circle, an ellipse, or the like. Lead-out portions 12a and 12b are led out directly from winding unit 11 toward first surface 30a and are disposed on the surface of first surface 30a.

[0168] In each of the above-described embodiments, the embedded portion 46 may be omitted from the terminal electrode 40b as shown in Fig. 22. The same applies to the terminal electrode 40a.

[0169] In (a-1) of FIG. 4A, the terminal electrodes 40a and 40b have a rectangular shape in a plan view, and the third sides 41a3 and 41b3 extend linearly. However, as shown in (a-1)' of FIG. 23, at least a portion of the third side 41a3 and at least a portion of the third side 41b3 may be curved in an arc shape. In the example shown in FIG. 23, the intersections of the third side 41a3 with the first side 41a1 and the second side 41a2 are curved in an arc shape. Furthermore, the intersections of the third side 41b3 with the first side 41b1 and the second side 41b2 are curved in an arc shape.

[0170] The same applies to the terminal electrodes 40a and 40b shown in (a-1) of Fig. 5A, and as shown in (a-1)'' of Fig. 23, at least a part of the third side 41a3 and at least a part of the third side 41b3 may be curved in an arc shape. The same applies to the terminal electrodes 40a and 40b shown in (a-1) of Fig. 6A, and as shown in (a-1)'' of Fig. 23, at least a part of the third side 41a3 and at least a part of the third side 41b3 may be curved in an arc shape.

[0171] In each of the above-described embodiments, the core 20 does not have to be a sintered body, and may be formed from the same material and by the same manufacturing method as the outer casing 30 .

[0172] This specification discloses the following:

[0173] [1] A coil component comprising: an element body containing magnetic particles and a resin and having a first surface; a coil located inside the element body; and a terminal electrode to which an extraction portion of the coil is connected and which contacts an electrode contact portion on the first surface, wherein the element body has a raised portion formed at least around the terminal electrode and raised relative to the electrode contact portion, and the raised portion is located on the outer edge of the first surface.

[0174] [2] The coil component according to the above [1], wherein the surface roughness of the raised portion is greater than the surface roughness of the terminal electrode.

[0175] [3] The coil component according to the above [1] or [2], wherein the terminal electrodes are connectable to a mounting board by a conductive bonding material, and the bonding strength of the surfaces of the protrusions to the conductive bonding material is lower than the bonding strength of the surfaces of the terminal electrodes to the conductive bonding material.

[0176] [4] The coil component according to any one of [1] to [3] above, wherein the height of the protrusion from the electrode contact portion is at least equal to or greater than the thickness of the outer edge portion of the terminal electrode.

[0177] [5] The coil component according to any one of the above [1] to [4], wherein the raised portion contains the magnetic particles having an average particle size equal to or greater than the thickness of the outer edge portion of the terminal electrode.

[0178] [6] The coil component according to any one of the above [1] to [5], wherein the raised portion extends along the outer periphery of the terminal electrode so as to overlap with the outer edge of the terminal electrode.

[0179] [7] The coil component according to any one of the above [1] to [6], wherein the outer periphery of the terminal electrode has a first side, a second side, and a third side located on the outer edge of the first surface, the third side connecting the first side and the second side and extending linearly or nonlinearly, and the raised portion extending along at least one of the first side and the second side.

[0180] [8] The coil component according to the above [7], wherein the protruding portion extends along at least one of the first side and the second side and the third side.

[0181] [9] The coil component according to any one of the above [1] to [6], wherein the outer periphery of the terminal electrode has a first side, a second side, and a third side located on the outer edge of the first surface, the third side connects the first side and the second side and extends linearly or nonlinearly, and the raised portion extends along the third side.

[0182]

[10] The coil component according to any one of [7] to [9], wherein the first side and the second side extend parallel to each other and face each other along the extension direction of the third side.

[0183]

[11] The coil component according to any one of the above [7] to [9], wherein the first side and the second side are inclined with respect to the third side.

[0184]

[12] The coil component according to any one of the above [7] to [9], wherein at least a part of the third side is curved in an arc shape.

[0185]

[13] The coil component according to any one of [7] to [9] above, wherein the first side, the second side, and the third side are continuous in an arc shape.

[0186]

[14] The coil component according to any of the above [1] to

[13] , wherein the terminal electrodes include a first terminal electrode to which a first lead-out portion of the coil is connected and a second terminal electrode facing the first terminal electrode and to which a second lead-out portion of the coil is connected, the outer edge portion of the first surface has a first outer edge portion and a second outer edge portion extending from the first terminal electrode toward the second terminal electrode, and a third outer edge portion and a fourth outer edge portion connecting the first outer edge portion and the second outer edge portion and extending linearly or nonlinearly, and the raised portion is located on at least one of the first outer edge portion and the second outer edge portion.

[0187]

[15] The coil component according to

[14] , wherein the protrusions are located on at least one of the first outer edge portion and the second outer edge portion, and at least one of the third outer edge portion and the fourth outer edge portion.

[0188]

[16] The coil component according to any of the above [1] to

[13] , wherein the terminal electrodes include a first terminal electrode to which a first lead-out portion of the coil is connected and a second terminal electrode facing the first terminal electrode and to which a second lead-out portion of the coil is connected, the outer edge portion of the first surface has a first outer edge portion and a second outer edge portion extending from the first terminal electrode toward the second terminal electrode, and a third outer edge portion and a fourth outer edge portion connecting the first outer edge portion and the second outer edge portion and extending linearly or nonlinearly, and the raised portion is located on at least one of the third outer edge portion and the fourth outer edge portion.

[0189]

[17] The coil component according to any one of

[14] to

[16] , wherein the first outer edge portion and the second outer edge portion extend in parallel and face each other along the extension direction of the third outer edge portion and the fourth outer edge portion.

[0190]

[18] The coil component according to any one of

[14] to

[16] , wherein each of the third outer edge portion and the fourth outer edge portion is bent at least at one location.

[0191]

[19] The coil component according to any one of

[14] to

[16] , wherein at least a part of the third outer edge portion and at least a part of the fourth outer edge portion are curved in an arc shape.

[0192]

[20] The coil component according to any one of

[14] to

[16] , wherein the first outer edge portion, the second outer edge portion, the third outer edge portion, and the fourth outer edge portion are continuous in a circular or elliptical shape.

[0193]

[21] The coil component according to any one of [1] to

[20] above, wherein the element body comprises a core having a core portion in which the coil is arranged and a flange portion formed at one axial end of the core portion, and an exterior body covering the core and the coil and having the protrusion portion, wherein the flange portion has an inner end surface connected to the core portion and an outer end surface facing the inner end surface, wherein the outer end surface has the electrode contact portion with which the terminal electrode comes into contact, and wherein the protrusion portion is in contact with the outer periphery of the outer end surface along the radial direction of the flange portion.

[0194]

[22] The coil component according to

[21] above, wherein the raised portion is located on an outer edge portion of the outer end surface of the flange portion.

[0195]

[23] The coil component according to the above

[21] or

[22] , wherein the flange portion has a side surface connecting the outer end surface and the inner end surface, and a chamfered portion formed on a ridge portion located between the outer end surface and the side surface, and the raised portion directly or indirectly covers at least a part of the chamfered portion.

[0196] DESCRIPTION OF SYMBOLS 1, 1A... Coil component 2, 2A... Element body 2b1, 2b2, 2b3, 2b4... First outer edge portion to fourth outer edge portion 10, 10A... Coil 11... Winding portion 12a, 12b... Lead-out portion 20... Core 21... Core portion 22... Flange portion 22a... Outer end surface 22b... Inner end surface 22c... Side surface 23... Chamfered portion 30, 30A... Outer body 30a to 30f... First surface to sixth surface 31... Curved portion 32... Unevenness 33... Unevenness pattern 35a, 35b, 35c, 35d, 35e, 35f, 35g, 35h, 35i, 35j, 35k, 35l... First ridge portion to twelfth ridge portion 36a, 36b... Electrode contact portion 37... Inter-electrode region 38...raised portion 40a, 40b...terminal electrodes 41a1, 41a2, 41a3, 41a4...first side to fourth side 41b1, 41b2, 41b3, 41b4...first side to fourth side 42...exposed portion 44, 46...embedded portion 50...partition portion 51...partition wall 51a...first end 51b...second end 51c...inner wall surface 52...partition space 53...first opening 53a...opening edge 54...second opening 55...bottom wall 56...through hole 56a...opening edge 60, 60A...mold 61...main body 62...cavity 63...inner wall 64...bottom surface 65...partition space 66...partition wall 66b...upper end 66c...inner wall surface 67...connection region 70: Partition region 72: Connection region 80: Sheathing material 90, 90A: Connection portion 100, 100A: Molded body 110: Release film 120: Adhesive sheet 130: Base

Claims

1. A coil component comprising: an element body containing magnetic particles and resin and having a first surface; a coil located inside the element body; and a terminal electrode to which an extraction portion of the coil is connected and which contacts an electrode contact portion on the first surface, wherein the element body has a raised portion formed at least around the terminal electrode and raised relative to the electrode contact portion, and the raised portion is located on the outer edge of the first surface.

2. A coil component according to claim 1, wherein the surface roughness of the raised portion is greater than the surface roughness of the terminal electrode.

3. A coil component according to claim 1 or 2, wherein the terminal electrodes are connectable to a mounting substrate by a conductive bonding material, and the bonding strength of the surfaces of the protrusions to the conductive bonding material is lower than the bonding strength of the surfaces of the terminal electrodes to the conductive bonding material.

4. A coil component according to claim 1 or 2, wherein the height of said protrusion from said electrode contact portion is at least equal to or greater than the thickness of the outer edge portion of said terminal electrode.

5. A coil component according to claim 1 or 2, wherein the raised portion contains magnetic particles having an average particle size equal to or greater than the thickness of the outer edge of the terminal electrode.

6. A coil component according to claim 1 or 2, wherein the raised portion extends along the outer periphery of the terminal electrode so as to overlap the outer edge of the terminal electrode.

7. A coil component as described in claim 6, wherein the outer periphery of the terminal electrode has a first side, a second side, and a third side located on the outer edge of the first surface, the third side connecting the first side and the second side and extending linearly or non-linearly, and the raised portion extending along at least one of the first side and the second side.

8. The coil component according to claim 7, wherein the raised portion extends along at least one of the first side and the second side and the third side.

9. A coil component as described in claim 6, wherein the outer periphery of the terminal electrode has a first side, a second side, and a third side located on the outer edge of the first surface, the third side connecting the first side and the second side and extending linearly or non-linearly, and the raised portion extending along the third side.

10. A coil component according to any one of claims 7 to 9, wherein the first side and the second side extend parallel to each other and face each other along the extension direction of the third side.

11. A coil component according to any one of claims 7 to 9, wherein the first side and the second side are inclined with respect to the third side.

12. A coil component according to any one of claims 7 to 9, wherein at least a portion of the third side is curved in an arc shape.

13. A coil component according to any one of claims 7 to 9, wherein the first side, the second side, and the third side are continuous in an arc shape.

14. A coil component as described in claim 1 or 2, wherein the terminal electrodes comprise a first terminal electrode to which a first lead-out portion of the coil is connected, and a second terminal electrode facing the first terminal electrode and to which a second lead-out portion of the coil is connected, the outer edge portion of the first surface has a first outer edge portion and a second outer edge portion extending from the first terminal electrode toward the second terminal electrode, and a third outer edge portion and a fourth outer edge portion connecting the first outer edge portion and the second outer edge portion and extending linearly or non-linearly, and the raised portion is located on at least one of the first outer edge portion and the second outer edge portion.

15. A coil component according to claim 14, wherein the raised portion is located on at least one of the first outer edge portion and the second outer edge portion, and at least one of the third outer edge portion and the fourth outer edge portion.

16. A coil component as described in claim 1 or 2, wherein the terminal electrodes comprise a first terminal electrode to which a first lead-out portion of the coil is connected, and a second terminal electrode facing the first terminal electrode and to which a second lead-out portion of the coil is connected, the outer edge portion of the first surface has a first outer edge portion and a second outer edge portion extending from the first terminal electrode toward the second terminal electrode, and a third outer edge portion and a fourth outer edge portion connecting the first outer edge portion and the second outer edge portion and extending linearly or non-linearly, and the raised portion is located on at least one of the third outer edge portion and the fourth outer edge portion.

17. A coil component according to claim 14, wherein the first outer edge portion and the second outer edge portion extend parallel to each other and face each other along the extension direction of the third outer edge portion and the fourth outer edge portion.

18. The coil component according to claim 16, wherein each of the third outer edge portion and the fourth outer edge portion is bent at least at one location.

19. The coil component according to claim 16, wherein at least a portion of the third outer edge portion and at least a portion of the fourth outer edge portion are curved in an arc shape.

20. A coil component according to claim 15, wherein the first outer edge portion, the second outer edge portion, the third outer edge portion, and the fourth outer edge portion are continuous in a circular or elliptical shape.

21. A coil component as described in claim 1 or 2, wherein the base body comprises a core having a core portion in which the coil is arranged and a flange portion formed at one axial end of the core portion, and an outer body covering the core and the coil and having the raised portion, the flange portion having an inner end face connected to the core portion and an outer end face opposite the inner end face, the outer end face having the electrode contact portion with which the terminal electrode comes into contact, and the raised portion contacting the outer periphery of the outer end face along the radial direction of the flange portion.

22. A coil component according to claim 21, wherein the raised portion is located on the outer edge of the outer end surface of the flange portion.

23. A coil component as described in claim 21, wherein the flange portion has a side surface connecting the outer end surface and the inner end surface, and a chamfered portion formed on a ridge portion located between the outer end surface and the side surface, and the raised portion directly or indirectly covers at least a portion of the chamfered portion.

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