Coil component

Abstract

Provided is a structure for a winding-type coil component structured with a wire wound on a core, the structure making it less likely for a metal terminal to detach from a flange portion of the core, the metal terminal being made of a metal plate attached to the flange portion.　The flange portions (3, 4) of the core (5) comprise: mounting surfaces (7, 8) that face a mounting substrate when mounted; top surfaces (9, 10) that face away from the mounting surfaces; inside end surfaces (11, 12) that connect the mounting surfaces and the top surfaces and face a winding core portion 2, and on which the ends in an axial direction L of the winding core portion are positioned; outside end surfaces (13, 14) facing away from the inside end surfaces; and first side surfaces (15, 16) and second side surfaces (17, 18) that connect the inside end surfaces and the outside end surfaces, and that face in the opposite directions from each other. Metal terminals (23, 24) are each made of a single metal plate and include mounting surface-opposing portions (25, 26), outside end surface-opposing portions (27, 28), first side surface-opposing portions (29, 30), and second side surface-opposing portions (31, 32) that are respectively opposite the mounting surfaces, the outside end surfaces, the first side surfaces, and the second side surfaces.

Description

Coil parts

[0001] The present invention relates to a wire-wound coil component having a structure in which a wire is wound around a core, and in particular to a form of a metal terminal made of a metal plate attached to the core.

[0002] For example, Japanese Patent Laid-Open Publication No. 2006-4989 (Patent Document 1) describes a wire-wound coil component having a structure in which a wire is wound around a core. More specifically, the core has a winding core portion extending in the axial direction and a pair of flange portions provided at opposite ends of the winding core portion in the axial direction. A metal terminal made of a metal plate is attached to each flange portion. A wire is wound around the winding core portion and connected to the metal terminals.

[0003] The flange portion has a mounting surface that faces the mounting board during mounting, a top surface that faces the opposite side of the mounting surface, an inner end surface that faces the winding core portion and positions the end of the winding core portion in the axial direction, and an outer end surface that faces the opposite side of the inner end surface.

[0004] On the other hand, the metal terminal has a mounting surface facing portion, an outer end face facing portion and a top face facing portion that face the mounting surface, outer end face and top face of the flange portion, respectively, and is connected from the mounting surface facing portion to the outer end face facing portion via a bent portion, and from the outer end face facing portion to the top face facing portion via a bent portion.

[0005] In the invention described in Patent Document 1, at least one of the angles formed between the outer end face of the flange and the mounting surface and the angle formed between the outer end face and the top surface is an acute angle, so that the flange is clamped between the mounting surface facing portion and the top surface facing portion, making it difficult for the metal terminal to come off the flange.

[0006] Furthermore, Patent Document 1 describes that the mounting surface and top surface of the flange are provided with recesses with circular openings, and the metal terminal is provided with spherical protrusions on the mounting surface-facing portion and top surface-facing portion. The fitting of the protrusions into the recesses makes it easier to position the metal terminal relative to the flange, and also makes it less likely for the metal terminal to become misaligned with the flange, which also contributes to making it less likely for the metal terminal to come off the flange.

[0007] Japanese Patent Application Laid-Open No. 2006-4989

[0008] External forces acting on the core, more specifically, external forces that can cause the metal terminal to come off the flange, are typically thought to come in six directions. These directions are two positive and negative directions along the axial direction of the winding core (hereinafter also referred to as the "L direction"); two positive and negative directions along the direction perpendicular to the L direction, connecting the mounting surface and the top surface (hereinafter also referred to as the "T direction"); and two positive and negative directions along the direction in which the mounting surface and the top surface extend (hereinafter also referred to as the "W direction"). Therefore, to prevent the metal terminal from coming off the flange, it is necessary to withstand external forces in these six directions. Note that the external force in the T direction from the mounting surface toward the top surface does not usually occur when the coil component is mounted on a mounting board, so it can be ignored.

[0009] In the coil component described in Patent Document 1, each of the pair of metal terminals has a mounting surface facing portion, an outer end surface facing portion, and a top surface facing portion, and therefore, in the mounted state, it is considered that the coil component can adequately withstand external forces from four directions, namely, two directions (positive and negative) in the T direction and two directions (positive and negative) in the L direction, because specific surfaces of the metal terminals abut against specific surfaces of the flange portion.

[0010] On the other hand, there is no portion that can withstand external forces in the two directions (positive and negative) in the W direction and achieve surface-to-surface contact. As mentioned above, Patent Document 1 describes that the mounting surface and top surface of the flange have circular recesses, and the mounting surface-facing and top surface-facing portions of the metal terminal have spherical protrusions. However, the resistance to external forces caused by the protrusions fitting into the recesses is weaker than the resistance to external forces caused by surface-to-surface contact, and the concern that the metal terminal may come off the flange cannot be completely ruled out.

[0011] Therefore, an object of the present invention is to provide a coil component having a structure that can further reduce the likelihood of the metal terminal coming off the flange portion, compared to the technology described in Patent Document 1.

[0012] The present invention is directed to a coil component comprising a core having a winding core portion extending in the axial direction and a pair of flange portions respectively provided at opposite ends of the winding core portion in the axial direction, a pair of metal terminals each made of a metal plate attached to each flange portion, and a wire connected to each of the pair of metal terminals and wound around the winding core portion.

[0013] Each flange portion has a mounting surface that faces the mounting board during mounting, a top surface that faces the opposite side of the mounting surface, an inner end surface that faces the winding core portion and positions the end of the winding core portion in the axial direction, an outer end surface that faces the opposite side of the inner end surface, and a first side surface and a second side surface that connect the inner end surface and the outer end surface and face in opposite directions to each other.

[0014] In this invention, in order to solve the above-mentioned technical problems, each metal terminal is characterized by having a mounting surface facing portion, an outer end surface facing portion, a first side surface facing portion, and a second side surface facing portion, which respectively face the mounting surface, the outer end surface, the first side surface facing portion, and the second side surface facing portion.

[0015] According to this invention, among the external forces acting on the core, external forces in at least five directions, namely, two positive and negative directions in the L direction, two positive and negative directions in the W direction, and a direction from the top surface toward the mounting surface in the T direction, can be withstood by surface-to-surface contact. Therefore, the metal terminal can sufficiently withstand external forces in at least the above five directions so as not to come off the flange, and compared to the technology described in Patent Document 1, the likelihood of the metal terminal coming off the flange can be further reduced.

[0016] 1 is a perspective view showing the appearance of a coil component 1 according to a first embodiment of the present invention, with mounting surfaces 7 and 8 facing upward; FIG. 2 is a perspective view showing the mounted state of the coil component 1 shown in FIG. 1; FIG. 3 is a perspective view for explaining a typical external force acting on the coil component 1 in the mounted state shown in FIG. 2; FIG. 4 is a perspective view for explaining an external force acting in the rotational direction on the coil component 1 in the mounted state shown in FIG. 2; FIG. 5 is a perspective view showing the appearance of a coil component 1a according to a second embodiment of the present invention, with mounting surfaces 7 and 8 facing upward; FIG. 6 is a perspective view showing the appearance of a coil component 1b according to a third embodiment of the present invention, with mounting surfaces 7 and 8 facing upward; FIG. 7 is a perspective view showing the appearance of a coil component 1c according to a fourth embodiment of the present invention, with mounting surfaces 7 and 8 facing upward; and FIG. 8 is a perspective view showing the appearance of a coil component 1d according to a fifth embodiment of the present invention, with mounting surfaces 7 and 8 facing upward.

[0017] A coil component 1 according to a first embodiment of the present invention will be described with reference to FIGS. 1 to 4. FIG.

[0018] The coil component 1 includes a drum-shaped core 5 having a winding core 2 extending in the axial direction (L direction) and a pair of flanges, i.e., a first flange 3 and a second flange 4, provided at opposite ends of the winding core 2 in the L direction. The core 5 is made of a magnetic material such as ferrite, a resin containing ferrite powder or metal magnetic powder, or a non-magnetic material such as alumina. In the drawing, the winding core 2 has a substantially rectangular cross-sectional shape, but may also have a polygonal shape such as a hexagon, a circle, an ellipse, or a combination of these shapes.

[0019] The first flange 3 has a mounting surface 7 that faces the mounting board 6 (see Figure 2) during mounting, a top surface 9 that faces the opposite side of the mounting surface 7, and connects the mounting surface 7 and the top surface 9.The first flange 3 has an inner end surface 11 that faces the winding core 2 and positions the end of the winding core 2 in the L direction, an outer end surface 13 that faces the opposite side of the inner end surface 11, and a first side surface 15 and a second side surface 17 that connect the inner end surface 11 and the outer end surface 13 and face in opposite directions to each other.

[0020] Similarly, the second flange portion 4 has a mounting surface 8 that faces the mounting board 6 during mounting, a top surface 10 that faces the opposite side of the mounting surface 8, an inner end surface 12 that faces the winding core portion 2 and positions the end of the winding core portion 2 in the L direction, an outer end surface 14 that faces the opposite side of the inner end surface 12, and a first side surface 16 and a second side surface 18 that connect the inner end surface 12 and the outer end surface 14 and face in opposite directions to each other.

[0021] The dimensions of the core 5 are not limited, but as an example, the dimension in the L direction is 3.2 mm, the dimension in the direction perpendicular to the L direction, in which the mounting surfaces 7 and 8 and the top surfaces 9 and 10 extend (W direction), is 2.5 mm, and the dimension in the direction connecting the mounting surfaces 7 and 8 and the top surfaces 9 and 10 (T direction) is 1.8 mm.

[0022] The coil component 1 constitutes, for example, a wire-wound inductor and includes a wire 21 wound around the winding core 2 of the core 5. The wire 21 includes, for example, a central wire made of a highly conductive metal such as copper, silver, or gold, and an insulating coating made of an electrically insulating resin such as polyamideimide, polyurethane, or polyesterimide that covers the central wire. The diameter of the central wire of the wire 21 is not important, but it is preferable to use one with a diameter of, for example, 80 μm or more and 200 μm or less. The number of turns of the wire 21 on the winding core 2 is also not important.

[0023] A pair of metal terminals 23 and 24 are attached to the flanges 3 and 4. More specifically, the first metal terminal 23 is attached to the first flange 3, and the second metal terminal 24 is attached to the second flange 4. The first and second ends of the wire 21, which are opposite to each other, are connected to the first and second metal terminals 23 and 24, respectively.

[0024] The first metal terminal 23 and the second metal terminal 24 are each made of a single metal plate and have substantially the same shape or point-symmetric shapes with each other. The metal plate constituting the metal terminals 23 and 24 may be, for example, a plate in which a base material made of phosphor bronze is plated with Ni and Sn.

[0025] The first metal terminal 23 has a mounting surface facing portion 25, an outer end face facing portion 27, a first side face facing portion 29, and a second side face facing portion 31 that respectively face the mounting surface 7, the outer end face 13, the first side face 15, and the second side face 17 of the first flange 3. The second metal terminal 24 has a mounting surface facing portion 26, an outer end face facing portion 28, a first side face facing portion 30, and a second side face facing portion 32 that respectively face the mounting surface 8, the outer end face 14, the first side face 16, and the second side face 18 of the second flange 4.

[0026] In this embodiment, in the first metal terminal 23, the outer end surface facing portion 27 is connected to the mounting surface facing portion 25 via a first bent portion 33, and the first side surface facing portion 29 and the second side surface facing portion 31 are connected to the mounting surface facing portion 25 via a second bent portion 35. Similarly, in the second metal terminal 24, the outer end surface facing portion 28 is connected to the mounting surface facing portion 26 via a first bent portion 34, and the first side surface facing portion 30 and the second side surface facing portion 32 are connected to the mounting surface facing portion 26 via a second bent portion 36.

[0027] The first and second ends of the wire 21 are connected to the mounting surface facing portion 25 of the first metal terminal 23 and the mounting surface facing portion 26 of the second metal terminal 24, respectively, by, for example, thermocompression bonding.

[0028] 2, the coil component 1 is mounted in a state in which the metal terminals 23 and 24 are connected via solder to conductive lands 37 and 38 provided on the mounting substrate 6. Fig. 2 also shows a fillet 39 formed by the solder connecting the conductive land 37 and the first metal terminal 23.

[0029] The coil component 1 is provided with a top plate 40 that connects the top surface 9 of the first flange 3 and the top surface 10 of the second flange 4 of the core 5. The top plate 40 is bonded to the core 5 with an adhesive. For example, a thermosetting epoxy resin is used as the adhesive. To improve the thermal shock resistance of the adhesive, an inorganic filler such as silica filler may be added to the adhesive. Methods for applying the adhesive include a printing method in which the adhesive is applied to the top plate 40, a method in which the top surfaces 9 and 10 of the flanges 3 and 4 of the core 5 are dipped in the adhesive, and a method in which the adhesive is dispensed onto both the top plate 40 and the core 5.

[0030] The top plate 40 may be made of a magnetic material such as ferrite, a resin containing ferrite powder or metallic magnetic powder, or a non-magnetic material such as alumina. When both the core 5 and the top plate 40 are made of magnetic materials, the core 5 and the top plate 40 form a closed magnetic circuit. A resin coating may be applied instead of the top plate 40. Note that the top plate 40 or the resin coating may not be necessary.

[0031] The above-described configuration provides the following advantageous effects.

[0032] Explaining with reference to Figures 1 to 4, when the coil component 1 is mounted, the core 5 can withstand external forces acting in two directions, positive and negative, in the L direction, through the abutment between the outer end face 13 of the first flange 3 and the outer end face opposing portion 27 of the first metal terminal 23, and the abutment between the outer end face 14 of the second flange 4 and the outer end face opposing portion 28 of the second metal terminal 24.

[0033] Furthermore, when the coil component 1 is mounted, the core 5 can withstand external forces acting in two directions, positive and negative, in the W direction, through the abutment between the first side surface 15 of the first flange 3 and the first side surface facing portion 29 of the first metal terminal 23, the abutment between the second side surface 17 of the first flange 3 and the second side surface facing portion 31 of the first metal terminal 23, the abutment between the first side surface 16 of the second flange 4 and the first side surface facing portion 30 of the second metal terminal 24, and the abutment between the second side surface 18 of the second flange 4 and the second side surface facing portion 32 of the second metal terminal 24.

[0034] Furthermore, when the coil component 1 is mounted, the external forces acting on the core 5 in the T direction from the top surfaces 9 and 10 toward the mounting surfaces 7 and 8 can be withstood by the abutment between the mounting surface 7 of the first flange 3 and the mounting surface facing portion 25 of the first metal terminal 23, and the abutment between the mounting surface 8 of the second flange 4 and the mounting surface facing portion 26 of the second metal terminal 24.

[0035] In this way, the metal terminals 23 and 24 can withstand external forces from at least the above five directions without coming off the flanges 3 and 4.

[0036] This embodiment has a structure that makes it even more difficult for the metal terminals 23 and 24 to come off the flanges 3 and 4. That is, the metal terminals 23 and 24 further have restricting portions that restrict at least the mounting surface facing portions 25 and 26 from moving in a direction away from the mounting surfaces 7 and 8 relative to the flanges 3 and 4.

[0037] As described above, among the external forces acting on the core 5, external forces in the T direction from the mounting surfaces 7 and 8 toward the top surfaces 9 and 10 do not normally occur when the coil component 1 is mounted on a mounting board, but they may occur instantaneously due to an impact when dropped, etc. The above-described restricting portion is effective against external forces acting on the core 5 that are directed from the mounting surfaces 7 and 8 toward the top surfaces 9 and 10 in the T direction.

[0038] More specifically, with respect to the first metal terminal 23, the regulating portion is provided by a first convex portion 41 provided on at least one of the first side surface 15 and the second side surface 17 of the first flange portion 3, and a notch portion 42 located on at least one of the first side surface facing portion 29 and the second side surface facing portion 31 of the first metal terminal 23 and which receives the first convex portion 41.

[0039] Furthermore, with regard to the second metal terminal 24, the regulating portion is provided by a first convex portion 43 provided on at least one of the first side surface 16 and the second side surface 18 of the second flange portion 4, and a notch portion 44 located on at least one of the first side surface facing portion 30 and the second side surface facing portion 32 of the second metal terminal 24 and which receives the first convex portion 43.

[0040] In this way, by selecting at least one of the first side surface facing portion 29 and the second side surface facing portion 31 of the first metal terminal 23 as the position where the cutout portion 42 is provided, it is possible to ensure a large area for the outer end surface facing portion 27 and the mounting surface facing portion 25 of the first metal terminal 23, which are subjected to a relatively large external force. The same can be said for the cutout portion 44 of the second metal terminal 24. Therefore, it is possible to further improve the effect of making it difficult for the metal terminals 23 and 24 to come off the flange portions 3 and 4.

[0041] In this embodiment, with respect to the first metal terminal 23, the first protrusion 41 is provided on both the first side surface 15 and the second side surface 17 of the first flange 3, and the notch 42 is located on both the first side surface facing portion 29 and the second side surface facing portion 31 of the first metal terminal 23. Also, with respect to the second metal terminal 24, the first protrusion 43 is provided on both the first side surface 16 and the second side surface 18 of the second flange 4, and the notch 44 is located on both the first side surface facing portion 30 and the second side surface facing portion 32 of the second metal terminal 24.

[0042] In this way, when the first convex portion 41 is provided on both the first side surface 15 and the second side surface 17 of the first flange portion 3 and the first convex portion 43 is provided on both the first side surface 16 and the second side surface 18 of the second flange portion 4, the metal terminals 23 and 24 are less likely to come off the flange portions 3 and 4, thereby further enhancing the effect.

[0043] The restricting portion formed by the combination of the first convex portions 41 and 43 and the cutout portions 42 and 44 as described above can restrict not only the movement of the mounting surface opposing portions 25 and 26 in the direction away from the mounting surfaces 7 and 8, but also the movement of the outer end surface opposing portions 27 and 28 in the direction away from the outer end surfaces 13 and 14.

[0044] In this embodiment, with respect to the first metal terminal 23, the first convex portion 41 provides a first raised wall 45 extending along the direction in which the top surface 9 of the first flange portion 3 and the mounting surface 7 face each other, and a second raised wall 46 extending along the direction in which the outer end surface 13 and the inner end surface 11 face each other, and the cutout portion 42 provides a first opposing wall 47 facing the first raised wall 45 and a second opposing wall 48 facing the second raised wall 46.

[0045] Furthermore, with regard to the second metal terminal 24, the first convex portion 43 provides a first raised wall 49 extending along the direction in which the top surface 10 of the second flange portion 4 and the mounting surface 8 face each other, and a second raised wall 50 extending along the direction in which the outer end surface 14 and the inner end surface 12 face each other, and the cutout portion 44 provides a first opposing wall 51 facing the first raised wall 49 and a second opposing wall 52 facing the second raised wall 50.

[0046] When viewed toward each of the first sides 15 and 16 and the second sides 17 and 18, it is preferable that the first upstanding walls 45 and 49 extend linearly parallel to the inner end faces 11 and 12, respectively, and the second upstanding walls 46 and 50 extend linearly parallel to the mounting faces 7 and 8, respectively.

[0047] In this way, since the first rising walls 45 and 49 extend linearly parallel to the inner end faces 11 and 12 and the second rising walls 46 and 50 extend linearly parallel to the mounting surfaces 7 and 8, it is possible to reliably prevent the metal terminals 23 and 24 from coming off the flange portions 3 and 4 without any bias in the direction in which the mounting surface facing portions 25 and 26 move away from the mounting surfaces 7 and 8 and in the direction in which the outer end face facing portions 27 and 28 move away from the outer end faces 13 and 14.

[0048] Furthermore, when viewed toward each of the first side surface 15 and the second side surface 17 of the first flange portion 3, the first convex portion 41 is positioned on the first side surface 15 and the second side surface 17 so as to contact the corner where the outer end surface 13 and the mounting surface 7 intersect, and the notch portion 42 is positioned a predetermined distance from the edge of the first side surface facing portion 29 and the second side surface facing portion 31 of the first metal terminal 23 on the inner end surface 11 side and the edge of the top surface 9 side. In other words, the first side surface facing portion 29 and the second side surface facing portion 31 form an L-shape that is biased toward the inner end surface 11 side and the top surface 9 side.

[0049] Similarly, when viewed toward each of the first side surface 16 and the second side surface 18 of the second flange portion 4, the first convex portion 43 is positioned on the first side surface 16 and the second side surface 18 so as to contact the corner where the outer end surface 14 and the mounting surface 8 intersect, and the notch portion 44 is positioned a predetermined distance from the edge of the first side surface facing portion 30 and the second side surface facing portion 32 of the second metal terminal 24 on the inner end surface 12 side and the top surface 10 side. In other words, the first side surface facing portion 30 and the second side surface facing portion 32 form an L-shape that is biased toward the inner end surface 12 side and the top surface 10 side.

[0050] The above-described arrangement of the first convex portions 41 and 43 and the cutout portions 42 and 44 allows for a large area for each of the first convex portions 41 and 43. Furthermore, the rising walls of the first convex portions 41 and 43 that extend along the mounting surfaces 7 and 8 are flush with the mounting surfaces 7 and 8, and the rising walls of the first convex portions 41 and 43 that extend along the outer end surfaces 13 and 14 are flush with the outer end surfaces 13 and 14, making it easy to mold the core 5 that includes the first convex portions 41 and 43.

[0051] Furthermore, it is preferable that the first flange portion 3 further includes a second convex portion 53 that faces at least a portion of the edge on the top surface 9 side of the first metal terminal 23 in the direction in which the top surface 9 and the mounting surface 7 face each other, and that the second flange portion 4 further includes a second convex portion 54 that faces at least a portion of the edge on the top surface 10 side of the second metal terminal 24 in the direction in which the top surface 10 and the mounting surface 8 face each other.

[0052] Such second protrusions 53 and 54 can more reliably prevent the metal terminals 23 and 24 from coming off the flanges 3 and 4 when subjected to the rotational external forces R1 and R2 shown in FIG. 4 . The rotational external force R1 occurs around an axis facing the W direction, and the rotational external force R2 occurs around an axis facing the L direction. Of these rotational external forces R1 and R2, the external force R1 can be generated, for example, when a temperature change occurs in a state in which the coil component 1 is mounted on the mounting substrate 6, due to a difference in thermal expansion between the core 5 and the mounting substrate 6, causing the mounting substrate 6 to thermally expand more than the core 5. These rotational external forces R1 and R2 act to move the outer end surface opposing portions 27 and 28 of the metal terminals 23 and 24 away from the core 5, causing the metal terminals 23 and 24 to come off the flanges 3 and 4.

[0053] In this embodiment, the second convex portion 53 is provided across the first side surface 15, outer end surface 13 and second side surface 17 of the first flange portion 3, and the second convex portion 54 is provided across the first side surface 16, outer end surface 14 and second side surface 18 of the second flange portion 4.

[0054] In terms of resistance to the rotational external forces R1 and R2 described above, it is particularly effective that the second convex portion 53 is arranged to face the edges of the first side surface facing portion 29 and the second side surface facing portion 31 of the first metal terminal 23 on the top surface 9 side, and that the second convex portion 54 is arranged to face the edges of the first side surface facing portion 30 and the second side surface facing portion 32 of the second metal terminal 24 on the top surface 10 side.

[0055] Although the outer end surface facing portions 27 and 28 of the metal terminals 23 and 24 may form a step on the outer end surfaces 13 and 14 sides of the flanges 3 and 4, the portions of the second protrusions 53 and 54 located on the outer end surfaces 13 and 14 contribute to eliminating or reducing such a step. Therefore, it is possible to make it less likely that the tip of a tool such as tweezers will get caught between the outer end surface facing portions 27 and 28 of the metal terminals 23 and 24 and the outer end surfaces 13 and 14 of the flanges 3 and 4.

[0056] Figures 5, 6, 7, and 8 are diagrams corresponding to Figure 1, showing a coil component 1a according to a second embodiment, a coil component 1b according to a third embodiment, a coil component 1c according to a fourth embodiment, and a coil component 1d according to a fifth embodiment of the present invention, respectively. In Figures 5 to 8, elements corresponding to the elements shown in Figure 1 or elements corresponding between Figures 5 to 8 are given the same reference numerals, and duplicated explanations will be omitted.

[0057] The coil component 1a shown in FIG. 5 differs from the coil component 1 shown in FIG. 1 in the shape and bending manner of the metal plates that form each of the metal terminals 23a and 24a.

[0058] More specifically, in the first metal terminal 23a, the outer end surface facing portion 27 is connected to the mounting surface facing portion 25 via the first bent portion 55, and the first side surface facing portion 29 and the second side surface facing portion 31 are each connected to the outer end surface facing portion 27 via the second bent portion 57.

[0059] Similarly, in the second metal terminal 24a, the outer end surface facing portion 28 is connected to the mounting surface facing portion 26 via the first bent portion 56, and the first side surface facing portion 30 and the second side surface facing portion 32 are each connected to the outer end surface facing portion 28 via the second bent portion 58.

[0060] The coil device 1b shown in FIG. 6 can be considered as a modification of the coil device 1a shown in FIG. 5 with respect to the metal terminals 23b and 24b.

[0061] More specifically, in the first metal terminal 23b, the mounting surface facing portion 25 is divided into a first mounting surface facing end portion 61 on the first side surface 15 side, a second mounting surface facing end portion 63 on the second side surface 17 side, and a mounting surface facing central portion 65 sandwiched between the first mounting surface facing end portion 61 and the second mounting surface facing end portion 63, and these first mounting surface facing end portion 61, second mounting surface facing end portion 63 and mounting surface facing central portion 65 are connected to the outer end surface facing portion 27 via the first bent portion 55.

[0062] Similarly, in the second metal terminal 24b, the mounting surface facing portion 26 is divided into a first mounting surface facing end portion 62 on the first side surface 16 side, a second mounting surface facing end portion 64 on the second side surface 18 side, and a mounting surface facing central portion 66 sandwiched between the first mounting surface facing end portion 62 and the second mounting surface facing end portion 64, and these first mounting surface facing end portion 62, second mounting surface facing end portion 64 and mounting surface facing central portion 66 are connected to the outer end surface facing portion 28 via the first bent portion 56.

[0063] In the coil component 1b shown in FIG. 6, when it is mounted on a mounting board, solder is applied to the mounting surface-facing central portions 65 and 66 of the metal terminals 23b and 24b.

[0064] On the other hand, in the first metal terminal 23b, a first end of the wire 21 is connected to either the first mounting surface facing end 61 or the second mounting surface facing end 63, for example, the first mounting surface facing end 61, and in the second metal terminal 24b, a second end of the wire 21 is connected to either the first mounting surface facing end 62 or the second mounting surface facing end 64, for example, the second mounting surface facing end 64.

[0065] 6 , as described above, mounting surface-facing central portions 65 and 66, to which solder is applied during mounting, are separated from first mounting surface-facing ends 61 and 26 or second mounting surface-facing ends 63 and 64, to which wire 21 may be connected. This makes it possible to make first mounting surface-facing ends 61 and 62 or second mounting surface-facing ends 63 and 64 less susceptible to loads such as heat and stress applied to mounting surface-facing central portions 65 and 66, and to make mounting surface-facing central portions 65 and 66 less susceptible to loads such as heat and stress applied to first mounting surface-facing ends 61 and 62 or second mounting surface-facing ends 63 and 64. This improves the reliability of connection between the mounting board and metal terminals 23b and 24b, and between metal terminals 23b and 24b and wire 21.

[0066] The coil device 1c shown in FIG. 7 can be considered as a modification of the coil device 1b shown in FIG. 6 with respect to the metal terminals 23c and 24c.

[0067] 6 , in the first metal terminal 23c, the mounting surface facing portion 25 is divided into a first mounting surface facing end portion 61 on the first side surface 15 side, a second mounting surface facing end portion 63 on the second side surface 17 side, and a mounting surface facing central portion 65 sandwiched between the first mounting surface facing end portion 61 and the second mounting surface facing end portion 63. The mounting surface facing central portion 65 is connected to the outer end surface facing portion 27 via a first bent portion 55, while the first mounting surface facing end portion 61 and the second mounting surface facing end portion 63 are connected to the first side surface facing portion 29 and the second side surface facing portion 31 via a third bent portion 67, respectively.

[0068] Similarly, in the second metal terminal 24c, the mounting surface facing portion 26 is divided into a first mounting surface facing end portion 62 on the first side surface 16 side, a second mounting surface facing end portion 64 on the second side surface 18 side, and a mounting surface facing central portion 66 sandwiched between the first mounting surface facing end portion 62 and the second mounting surface facing end portion 64. The mounting surface facing central portion 66 is connected to the outer end surface facing portion 28 via a first bent portion 56, while the first mounting surface facing end portion 62 and the second mounting surface facing end portion 64 are connected to the first side surface facing portion 30 and the second side surface facing portion 32 via a third bent portion 68, respectively.

[0069] In the coil component 1c shown in Figure 7, as in the case of the coil component 1b shown in Figure 6, when it is mounted on a mounting board, solder is applied to the mounting surface-facing central portions 65 and 66 of the metal terminals 23c and 24c.

[0070] Furthermore, in the first metal terminal 23c, a first end of the wire 21 is connected to either the first mounting surface facing end 61 or the second mounting surface facing end 63, for example, the first mounting surface facing end 61, and in the second metal terminal 24c, a second end of the wire 21 is connected to either the first mounting surface facing end 62 or the second mounting surface facing end 64, for example, the second mounting surface facing end 64.

[0071] 6 , the coil component 1c shown in FIG. 7 has mounting surface-facing central portions 65 and 66 to which solder is applied during mounting, and mounting surface-facing end portions 61-64 to which wire 21 may be connected, which are separated from each other. However, in the coil component 1c shown in FIG. 7 , the mounting surface-facing end portions 61-64 are connected to the outer end surface-facing portions 27 and 28 via the side surface-facing portions 29-32. Therefore, compared to the coil component 1b shown in FIG. 6 , the mounting surface-facing end portions 61-64 are less susceptible to the effects of loads such as heat and stress on the mounting surface-facing central portions 65 and 66, and the mounting surface-facing central portions 65 and 66 are less susceptible to the effects of loads such as heat and stress on the mounting surface-facing end portions 61-64. Therefore, the connection reliability between the mounting board and the metal terminals 23c and 24c, and the connection reliability between the metal terminals 23c and 24c and the wire 21 can be improved compared to the coil component 1b shown in FIG. 6 .

[0072] The coil component 1d shown in FIG. 8 differs from the coil component 1a shown in FIG. 5 in the positions of the first protrusions 41d and 43d.

[0073] 5, the first protrusion 41 is positioned on the first side surface 15 and the second side surface 17 of the first flange 3 so as to contact the corner where the outer end surface 13 intersects with the mounting surface 7, and the first protrusion 43 is positioned on the first side surface 16 and the second side surface 18 of the second flange 4 so as to contact the corner where the outer end surface 14 intersects with the mounting surface 8. In contrast, in the coil component 1d shown in FIG. 8, the first protrusion 41d is positioned on the first side surface 15 and the second side surface 17 of the first flange 3, away from the corner where the outer end surface 13 intersects with the mounting surface 7, and the first protrusion 43d is positioned on the first side surface 16 and the second side surface 18 of the second flange 4, away from the corner where the outer end surface 14 intersects with the mounting surface 8.

[0074] In accordance with the above-described changes to the first protrusions 41d and 43d, the positions of the notches 42d and 44d provided in the metal terminals 23d and 24d are also changed.

[0075] The functions of the first protrusions 41 d and 43 d are substantially the same as those of the first protrusions 41 and 43 .

[0076] Although the present invention has been described above with reference to the illustrated embodiment, various other embodiments are possible within the scope of the present invention.

[0077] For example, a restricting portion that restricts the movement of at least the mounting surface facing portions 25 and 26 of the metal terminals 23 and 24 relative to the flange portions 3 and 4 in a direction away from the mounting surfaces 7 and 8 is not essential to this invention, but if a restricting portion is provided, it may be provided in association with only one of the first side surface 15 and the second side surface 17 of the first flange portion 3, or in association with only one of the first side surface 16 and the second side surface 18 of the second flange portion 4.

[0078] In addition, in the present invention, fixing with an adhesive is not essential when attaching the metal terminals 23 and 24 to the flanges 3 and 4. However, fixing with an adhesive can encounter the following problems.

[0079] (1) The stronger the adhesive fixation, the less useful the metal terminal becomes. The advantage of a metal terminal is that, due to the springiness of the metal plate, even if a small external force is applied, the metal terminal itself deflects, releasing the stress and preventing damage. However, the more firmly the metal terminal is fixed with adhesive, the less the springiness of the metal plate can be utilized. In other words, the terminal becomes vulnerable to the development of solder cracks during long-term reliability tests and to deflection tests.

[0080] (2) Adhesives are generally sensitive to heat and lose their adhesive properties after being exposed to temperatures of around 300°C for just a few minutes. However, when manufacturing coil components using conventional metal terminals, it is necessary to attach the metal terminals to the core and then connect the wire to the metal terminals using heat, which inevitably results in the adhesive being exposed to heat.

[0081] However, according to the present invention, adhesive is not required for attachment of the metal terminals 23 and 24 to the flanges 3 and 4, and sufficient heat can be applied when connecting the wires to the metal terminals. This allows for the use of relatively thick wires in the coil component. However, the present invention does not exclude the use of adhesives. Furthermore, when constructing a coil component according to the present invention, partial substitution or combination of the configurations among the different embodiments described in this specification is possible.

[0082] The embodiments of the present invention include the following:

[0083] <1> A core having a winding core portion extending in an axial direction and a pair of flange portions provided at opposite ends of the winding core portion in the axial direction; a pair of metal terminals each made of a metal plate attached to each of the flange portions; and a wire connected to each of the pair of metal terminals and wound around the winding core portion, wherein each of the flange portions has a mounting surface that faces a mounting board when mounted, a top surface that faces the opposite side of the mounting surface, an inner end surface that connects the mounting surface and the top surface and faces the winding core portion and positions an end of the winding core portion in the axial direction, an outer end surface that faces the opposite side of the inner end surface, and a first side surface and a second side surface that connect the inner end surface and the outer end surface and face in opposite directions to each other, each of the metal terminals has the mounting surface, the outer end surface, a mounting surface facing portion facing the first side surface and the second side surface, an outer end surface facing portion, a first side surface facing portion and a second side surface facing portion, respectively;

[0084] <2> The coil component according to <1>, wherein the outer end surface facing portion is connected to the mounting surface facing portion via a first bent portion, and the first side surface facing portion and the second side surface facing portion are connected to the mounting surface facing portion via a second bent portion.

[0085] <3> The coil component according to <1>, wherein the outer end surface facing portion is continuous with the mounting surface facing portion via a first bent portion, and the first side surface facing portion and the second side surface facing portion are continuous with the outer end surface facing portion via a second bent portion.

[0086] <4> The coil component according to <3>, wherein the mounting surface facing portion is divided into a first mounting surface facing end portion on the first side surface side, a second mounting surface facing end portion on the second side surface side, and a mounting surface facing central portion sandwiched between the first mounting surface facing end portion and the second mounting surface facing end portion, and the first mounting surface facing end portion, the second mounting surface facing end portion, and the mounting surface facing central portion are connected to the outer end surface facing portion via the first bent portion.

[0087] <5> The coil component according to any one of <1> to <4>, further comprising a restricting portion for restricting movement of at least the mounting surface facing portion relative to the flange portion in a direction away from the mounting surface.

[0088] <6> The coil component according to <5>, wherein the restricting portion is defined by a first convex portion provided on at least one of the first side surface and the second side surface of each of the pair of flange portions, and a cutout portion located on at least one of the first side surface facing portion and the second side surface facing portion of the metal terminal and receiving each of the first convex portions.

[0089] <7> The coil component according to <6>, wherein the restricting portion restricts movement of the mounting surface opposing portion not only in a direction away from the mounting surface but also in a direction away from the outer end surface opposing portion.

[0090] <8> The coil component according to <6> or <7>, wherein the first convex portion provides a first rising wall extending in a direction in which the top surface and the mounting surface face each other and a second rising wall extending in a direction in which the outer end surface and the inner end surface face each other, and the cutout portion provides a first opposing wall opposing the first rising wall and a second opposing wall opposing the second rising wall.

[0091] <9> The coil component according to <8>, wherein, when viewed toward each of the first side surface and the second side surface, the first upright wall extends linearly parallel to the inner end surface, and the second upright wall extends linearly parallel to the mounting surface.

[0092] <10> The coil component according to any one of <6> to <9>, wherein, when viewed toward each of the first side surface and the second side surface, the first convex portion is positioned so as to contact a corner where the outer end surface and the mounting surface intersect on at least one of the first side surface and the second side surface of each of the pair of flange portions, and the cutout portion is positioned at a predetermined distance from an edge on the inner end surface side and an edge on the top surface side of at least one of the first side surface facing portion and the second side surface facing portion of the metal terminal.

[0093] <11> The coil component according to any one of <5> to <10>, wherein the restricting portion is provided in association with both the first side surface and the second side surface of each of the pair of flange portions.

[0094] <12> The coil component according to any one of <1> to <11>, wherein each of the pair of flange portions further includes a second protrusion facing at least a part of an edge of the metal terminal on the top surface side.

[0095] <13> The coil component according to <12>, wherein the second protrusion faces edges of the first side surface facing portion and the second side surface facing portion of the metal terminal on the top surface side.

[0096] DESCRIPTION OF SYMBOLS 1, 1a, 1b, 1c, 1d Coil component 2 Winding core 3 First flange 4 Second flange 5 Core 6 Mounting board 7, 8 Mounting surface 9, 10 Top surface 11, 12 Inner end surface 13, 14 Outer end surface 15, 16 First side surface 17, 18 Second side surface 21 Wire 23, 23a, 23b, 23c, 23d First metal terminal 24, 24a, 24b, 24c, 24d Second metal terminal 25, 26 Mounting surface facing portion 27, 28 Outer end surface facing portion 29, 30 First side surface facing portion 31, 32 Second side surface facing portion 33, 34, 55, 56 First bent portion 35, 36, 57, 58 Second bent portion 37, 38 Conductive land 39 Fillet 41, 43, 41d, 43d First convex portion 42, 44, 42d, 44d Notch portion 45, 49 First rising wall 46, 50 Second rising wall 47, 51 First opposing wall 48, 52 Second opposing wall 53, 54 Second convex portion 61, 62 First mounting surface opposing end portion 63, 64 Second mounting surface opposing end portion 65, 66 Mounting surface opposing center portion

Claims

1. a core having a winding core portion extending in an axial direction and a pair of flange portions provided at opposite ends of the winding core portion in the axial direction; a pair of metal terminals each made of a metal plate attached to each of the flanges; a wire connected to each of the pair of metal terminals and wound around the winding core; Equipped with each of the flange portions has a mounting surface that faces the mounting board during mounting, a top surface that faces the opposite side to the mounting surface, and connects the mounting surface and the top surface, and has an inner end surface that faces the winding core portion and positions an end of the winding core portion in the axial direction, an outer end surface that faces the opposite side to the inner end surface, and a first side surface and a second side surface that connect the inner end surface and the outer end surface and face in opposite directions to each other, Each of the metal terminals has the mounting surface, the outer end surface, a mounting surface facing portion facing the first side surface and the second side surface, an outer end surface facing portion, a first side surface facing portion and a second side surface facing portion, Coil parts.

2. 2. The coil component according to claim 1, wherein the outer end face facing portion is connected to the mounting surface facing portion via a first bent portion, and the first side face facing portion and the second side face facing portion are connected to the mounting surface facing portion via a second bent portion.

3. 2. The coil component according to claim 1, wherein the outer end surface facing portion is connected to the mounting surface facing portion via a first bent portion, and the first side surface facing portion and the second side surface facing portion are connected to the outer end surface facing portion via a second bent portion.

4. the mounting surface facing portion is divided into a first mounting surface facing end portion on the first side surface side, a second mounting surface facing end portion on the second side surface side, and a mounting surface facing central portion sandwiched between the first mounting surface facing end portion and the second mounting surface facing end portion, the first mounting surface facing end portion, the second mounting surface facing end portion, and the mounting surface facing central portion are connected to the outer end surface facing portion via the first bent portion. The coil component according to claim 3 .

5. The coil component according to claim 1 , further comprising a restricting portion for restricting movement of the metal terminal relative to the flange portion in a direction away from the mounting surface at least of the mounting surface facing portion.

6. 6. The coil component according to claim 5, wherein the regulating portion is provided by a first convex portion provided on at least one of the first side surface and the second side surface of each of the pair of flange portions, and a cutout portion located on at least one of the first side surface facing portion and the second side surface facing portion of the metal terminal and receiving each of the first convex portions.

7. The coil component according to claim 6 , wherein the restricting portion restricts movement of the mounting surface opposing portion not only in a direction away from the mounting surface but also in a direction away from the outer end surface.

8. 7. The coil component according to claim 6, wherein the first convex portion provides a first rising wall extending along the opposing direction between the top surface and the mounting surface and a second rising wall extending along the opposing direction between the outer end surface and the inner end surface, and the cutout portion provides a first opposing wall opposing the first rising wall and a second opposing wall opposing the second rising wall.

9. 9. The coil component according to claim 8, wherein when viewed toward each of the first side surface and the second side surface, the first upright wall extends linearly parallel to the inner end surface, and the second upright wall extends linearly parallel to the mounting surface.

10. when viewed toward each of the first side surface and the second side surface, the first protrusion is positioned so as to be in contact with a corner at which the outer end surface and the mounting surface intersect on at least one of the first side surface and the second side surface of each of the pair of flange portions, the notch portion is positioned at a predetermined distance from an edge of the inner end face side and an edge of the top face side of at least one of the first side facing portion and the second side facing portion of the metal terminal; The coil component according to claim 6.

11. The coil component according to claim 5 , wherein the restricting portion is provided in association with both the first side surface and the second side surface of each of the pair of flange portions.

12. 2. The coil component according to claim 1, wherein each of the pair of flange portions further includes a second protrusion that faces at least a portion of an edge of the metal terminal on the top surface side in a direction in which the top surface and the mounting surface face each other.

13. The coil component according to claim 12 , wherein the second protrusion faces edges of the first side facing portion and the second side facing portion of the metal terminal on the top surface side.