Coil component and method for manufacturing the coil component

Abstract

This coil component comprises a coil, a plate-like electrode terminal, and a first connection member which connects a first end section of the coil and the electrode terminal, wherein: the electrode terminal includes a coil connection part connected to the first end section of the coil; the coil connection part includes a first primary surface, a second primary surface facing the first primary surface, and a side surface which connects the first primary surface and the second primary surface; the coil connection part has a first recess section open in the first primary surface, the second primary surface, and the side surface; the first end section of the coil is disposed only on the first primary side of the coil connection part to face the first primary surface, and is disposed so as to overlap the first recess section when viewed in a direction perpendicular to the first primary surface; and at least a portion of the first connection member is positioned inside the first recess section and is in contact with the inner surface of the first recess section.

Description

[Technical field]

[0001] The present disclosure relates to a coil component and a method for manufacturing a coil component. [Background technology]

[0002] A conventional coil component is described in JP 2000-182838 A (Patent Document 1). This coil component has a rod-shaped core, a wire wound around the rod-shaped core, and electrode terminals provided on both ends of the rod-shaped core. The wire is wound (entangled) around the electrode terminal and connected by soldering. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] JP 2000-182838 A Summary of the Invention [Problem to be solved by the invention]

[0004] In the conventional coil components, the wire is wound around the electrode terminal for connection, and there is a risk that the electrode terminal may be deformed when the wire is wound around the electrode terminal or due to residual stress remaining in the wound wire. In particular, when a thick wire is wound around a thin electrode terminal for connection, the electrode terminal is deformed, making the winding itself difficult. In addition, when the wire is wound around the electrode terminal, bending and bulging occur in the wire, which may cause a gap between the wire and the electrode terminal, making it difficult to achieve stable connection and miniaturization.

[0005] In view of the above, an object of the present disclosure is to provide a coil component that can be connected to an electrode terminal without the need to entangle the coil, and a method for manufacturing the coil component. [Means for solving the problem]

[0006] In order to solve the above problems, a coil component according to one aspect of the present disclosure comprises: A coil and A plate-shaped electrode terminal; a first connection member that connects a first end of the coil and the electrode terminal, the electrode terminal includes a coil connection portion connected to the first end of the coil, the coil connection portion includes a first main surface, a second main surface opposite to the first main surface, and a side surface connecting the first main surface and the second main surface, the coil connection portion has a first recess that opens to the first principal surface, the second principal surface, and the side surface, the first end of the coil is disposed only on the first main surface side of the coil connection portion, facing the first main surface, and overlapping with the first recess when viewed from a direction perpendicular to the first main surface; At least a portion of the first connection member is located within the first recess and is in contact with an inner surface of the first recess.

[0007] According to the above aspect, the first end of the coil and the electrode terminal are connected such that the first end is disposed only on the first main surface side of the coil connection portion of the electrode terminal and faces the first main surface, so that the coil is not connected to the electrode terminal in a tangled manner. Here, "tangled" means that the coil is wound around the electrode terminal.

[0008] Therefore, it is possible to prevent deformation of the electrode terminal caused by the coil winding work or residual stress of the wound coil. This allows a thick coil to be connected to a thin electrode terminal, and allows the use of electrode terminals that are easy to bend and coils that can handle large currents. In addition, since the coil is not wound around the electrode terminal, bending bulges do not occur in the coil, making it difficult for gaps to occur between the coil and the electrode terminal, achieving connection stability and miniaturization.

[0009] According to the above aspect, since at least a portion of the first connection member is located in the first recess of the electrode terminal, the first connection member can be observed from the second main surface side of the coil connection portion, which makes it easy to visually inspect the connection state between the coil and the electrode terminal.

[0010] Preferably, in one embodiment of the coil component, The first connection member is a welded portion at which the first end of the coil and the coil connection portion of the electrode terminal are welded together.

[0011] According to the embodiment, since the first end of the coil and the electrode terminal are welded, the connection strength between the coil and the electrode terminal can be increased. Also, the electrical resistance between the coil and the electrode terminal can be reduced. This reduces the electrical resistance of the coil component.

[0012] Preferably, in one embodiment of the coil component, The circumferential surface of the first end of the coil has a flat surface; The flat surface faces the first main surface.

[0013] According to the embodiment, the flat surface of the first end of the coil is connected to the electrode terminal via the first connection member. Therefore, the contact area between the first end of the coil and the electrode terminal can be increased, and the mechanical strength between the coil and the electrode terminal can be improved. In addition, the cross-sectional area of ​​the electrical path between the coil and the electrode terminal is increased, and the electrical resistance of the coil component can be reduced.

[0014] Preferably, in one embodiment of the coil component, The coil includes a plurality of straight pin members and a plurality of bent pin members, the straight pin members and the bent pin members are alternately connected to form the spiral of the coil; the plurality of straight pin members includes an end straight pin member located at an end on at least one side of the coil in an axial direction, the first end of the coil includes the endmost straight pin member; a peripheral surface of the outermost straight pin member faces the first main surface and overlaps with the first recess when viewed in a direction perpendicular to the first main surface; The first connection member connects the electrode terminal and the peripheral surface of the endmost straight pin member.

[0015] According to the above embodiment, a plurality of straight pin members and a plurality of bent pin members are alternately connected to form the spiral of the coil, so that when winding the coil around the core, the coil can be wound close to the core.

[0016] Preferably, in one embodiment of the coil component, a second connection member that connects the first end of the coil and the electrode terminal; the coil connection portion has a second recess that opens to the first main surface, the second main surface, and the side surface, the plurality of bent pin members include adjacent bent pin members connected adjacent to the endmost straight pin member, The end straight pin member and the adjacent bent pin member are connected to each other at an end surface of the end of the end straight pin member and a peripheral surface of an end of the adjacent bent pin member, the first end of the coil further includes the adjacent folded pin member; an end surface of the adjacent bent pin member on a side to which the outermost straight pin member is connected faces the first main surface and overlaps an inner surface of the second recess when viewed from a direction perpendicular to the first main surface; At least a portion of the second connection member is located within the second recess and contacts an inner surface of the second recess; The second connection member connects the electrode terminal and the end surface of the adjacent bent pin member.

[0017] According to the embodiment, since the second connection member is further provided, the mechanical strength between the coil and the electrode terminal can be further improved, and since the cross-sectional area of ​​the electrical path between the coil and the electrode terminal is increased, the electrical resistance of the coil component can be further reduced.

[0018] Preferably, in one embodiment of the coil component, The coil includes a plurality of straight pin members and a plurality of bent pin members, the straight pin members and the bent pin members are alternately connected to form the spiral of the coil; the plurality of bending pin members include an end bending pin member located at an end on at least one side of the coil in the axial direction, the first end of the coil includes the endmost bent pin member, an end surface of the outermost bent pin member opposite to the side to which the straight pin member is connected faces the first main surface and is disposed so as to overlap with the first recess when viewed from a direction perpendicular to the first main surface; The first connection member connects the electrode terminal and the end face of the outermost bent pin member.

[0019] According to the above embodiment, a plurality of straight pin members and a plurality of bent pin members are alternately connected to form the spiral of the coil, so that when winding the coil around the core, the coil can be wound close to the core.

[0020] Preferably, in one embodiment of the coil component, the electrode terminal further includes a mounting portion to be mounted on a mounting board, and a relay portion connecting the coil connection portion and the mounting portion, The coil connection portion and the mounting portion are not on the same plane and do not overlap when viewed in a direction perpendicular to the first main surface.

[0021] According to the embodiment, the relay section and the coil connection section are easily bent with the mounting section as a fulcrum, so that the springiness in the direction perpendicular to the first main surface of the coil connection section can be imparted to the electrode terminal. This allows the coil connection section and the first end of the coil to be in more reliable contact with each other when connecting the coil connection section and the first end of the coil, improving the connection stability between the coil and the electrode terminal. Furthermore, even if an external impact is applied to the coil component, the springiness of the electrode terminal can reduce the stress applied to the first connection member or the second connection member, thereby improving the reliability of the coil component.

[0022] Preferably, in one embodiment of the coil component, The electrode terminal is elastically deformable so that the coil connection portion can swing in a direction perpendicular to the first main surface.

[0023] According to the embodiment, the connection stability between the coil and the electrode terminal can be further improved. Also, even if an external impact is applied to the coil component, the stress applied to the first connection member or the second connection member can be further reduced, and the reliability of the coil component can be further improved.

[0024] Preferably, in one embodiment of the method for manufacturing a coil component, a step of disposing a first end of the coil only on a first main surface side of a coil connection portion of the electrode terminal, facing the first main surface, and overlapping a first recess provided in the electrode terminal when viewed from a direction perpendicular to the first main surface; forming a first connection member by irradiating at least a part of an inner surface of the first recess with a laser from a second main surface side of the coil connection portion; Equipped with.

[0025] According to the embodiment, the coil can be connected to the electrode terminal without being entangled, and the coil component can be made smaller.

[0026] In order to solve the above problems, a coil component according to one aspect of the present disclosure comprises: A coil and A plate-shaped electrode terminal; a first connection member that connects a first end of the coil and the electrode terminal, the electrode terminal includes a coil connection portion connected to the first end of the coil, a mounting portion mounted on a mounting board, and a relay portion connecting the coil connection portion and the mounting portion, The coil connection portion includes a first main surface and a second main surface opposite to the first main surface, the first end of the coil is disposed only on the first main surface side of the coil connection portion and faces the first main surface, The coil connection portion and the mounting portion are not on the same plane and do not overlap when viewed in a direction perpendicular to the first main surface.

[0027] According to the above aspect, the first end of the coil and the electrode terminal are connected so that the first end is disposed only on the first main surface side of the coil connection portion of the electrode terminal and faces the first main surface, so that the coil is not wound around the electrode terminal. Therefore, it is possible to prevent deformation of the electrode terminal caused by the coil winding operation or residual stress of the wound coil. This allows a thick coil to be connected to a thin electrode terminal, and allows the use of an electrode terminal that is easy to bend and a coil that is compatible with a large current. In addition, since the coil is not wound around the electrode terminal, bending bulges do not occur in the coil, and therefore gaps are less likely to occur between the coil and the electrode terminal, and connection stability and miniaturization can be achieved.

[0028] In addition, since the coil connection portion and the mounting portion are not on the same plane and do not overlap when viewed from a direction perpendicular to the first main surface of the coil connection portion, the relay portion and the coil connection portion are easily bent with the mounting portion as a fulcrum. This allows the electrode terminal to be given springiness in a direction perpendicular to the first main surface of the coil connection portion. As a result, when the coil connection portion and the first end of the coil are connected to each other, the coil connection portion and the first end of the coil can be more reliably brought into contact with each other, thereby improving the connection stability between the coil and the electrode terminal. Furthermore, even if an external impact is applied to the coil component, the springiness of the electrode terminal can reduce the stress applied to the first connection member, thereby improving the reliability of the coil component. Effect of the Invention

[0029] According to the coil component and the manufacturing method of the coil component according to one aspect of the present disclosure, it is possible to connect the coil to an electrode terminal without having to entangle the coil. [Brief description of the drawings]

[0030] [Figure 1] FIG. 1 is a top perspective view showing a coil component according to a first embodiment of the present invention. [Diagram 2] FIG. [Diagram 3] FIG. 2 is a top perspective view showing the inside of the coil component. [Figure 4]FIG. [Diagram 5] FIG. 2 is a schematic cross-sectional view of a coil component. [Figure 6] FIG. 2 is a schematic cross-sectional view of a coil component. [Figure 7] FIG. 4 is a schematic plan view partially showing an electrode terminal before being connected to a coil. [Figure 8] FIG. 8 is a cross-sectional view taken along line VIII-VIII of FIG. 7. [Figure 9] 4 is a schematic plan view partially showing a connection portion between a coil and an electrode terminal. FIG. [Figure 10] XX cross-sectional view of Figure 9. [Figure 11A] 5 is a schematic plan view illustrating a method of connecting a coil and an electrode terminal. FIG. [Figure 11B] 5 is a schematic plan view illustrating a method of connecting a coil and an electrode terminal. FIG. [Figure 12] FIG. 11 is a schematic cross-sectional view partially showing a coil component according to a second embodiment. [Figure 13] FIG. 11 is a schematic plan view partially illustrating a coil component according to a third embodiment. [Figure 14] FIG. 13 is a schematic plan view partially showing a coil component according to a fourth embodiment. [Figure 15] FIG. 13 is a schematic plan view partially illustrating a coil device according to a fifth embodiment. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0031] Hereinafter, a coil device according to one aspect of the present disclosure will be described in detail with reference to the illustrated embodiments. Note that the drawings include some schematic views and may not reflect actual dimensions or proportions.

[0032] (First embodiment) (Coil component configuration) Fig. 1 is a top perspective view showing a coil component according to an embodiment of the present invention. Fig. 2 is a bottom perspective view of the coil component. Fig. 3 is a top perspective view showing the inside of the coil component. Fig. 4 is an exploded perspective view of the coil component.

[0033] 1 to 4, the coil component 1 includes a case 2, an inductor element L housed in the case 2, first to fourth electrode terminals 51 to 54 attached to the case 2, a first connection member 81 connecting the inductor element L and the first to fourth electrode terminals 51 to 54, and a resin member 90 disposed in the case 2. The coil component 1 is, for example, a common mode choke coil. The inductor element L includes an annular core 3, a first coil 41 and a second coil 42 wound around the core 3, and a core cover 60 attached to the core 3.

[0034] The case 2 has a bottom plate portion 21 and a box portion 22 that covers the bottom plate portion 21. The case 2 is made of a material having strength and heat resistance, and preferably a material having flame retardancy. The case 2 is made of, for example, a resin such as PPS (polyphenylene sulfide), LCP (liquid crystal polymer), or PPA (polyphthalamide), or ceramics.

[0035] The bottom plate portion 21 has a bottom portion 210 including a first main surface 210a and a second main surface 210b facing each other, and a side wall portion 211 provided on the first main surface 210a of the bottom portion 210 along the outer periphery of the bottom portion 210. The bottom plate portion 21 has a recessed portion 215, and the recessed portion 215 is surrounded by the bottom portion 210 and the side wall portion 211. The side wall portion 211 is provided continuously in the circumferential direction, but may be provided intermittently in the circumferential direction. The bottom portion 210 has a plurality of openings 216 penetrating the first main surface 210a and the second main surface 210b. The plurality of openings 216 are provided at positions corresponding to the first to fourth electrode terminals 51 to 54. In this embodiment, the number of openings 216 is four, but the number may be increased or decreased as desired.

[0036] The inductor element L is disposed on the bottom plate portion 21. That is, the core 3 is disposed on the bottom plate portion 21 such that the central axis of the core 3 is perpendicular to the first main surface 210a of the bottom portion 210. The central axis of the core 3 refers to the central axis of the inner diameter hole portion of the core 3. The shape of the case 2 (bottom plate portion 21 and box portion 22) is rectangular when viewed from the central axis direction of the core 3. In this embodiment, the shape of the case 2 is rectangular.

[0037] Here, the short side direction of the case 2 as viewed from the central axis direction of the core 3 is the X direction, the long side direction of the case 2 as viewed from the central axis direction of the core 3 is the Y direction, and the height direction of the case 2 perpendicular to both the short side direction and the long side direction is the Z direction. The bottom plate part 21 and the box part 22 of the case 2 are arranged facing each other in the Z direction, with the bottom plate part 21 on the lower side and the box part 22 on the upper side, with the upper side being the forward direction of the Z direction and the lower side being the reverse direction of the Z direction. In other words, in the height direction perpendicular to the first main surface 210a, the direction from the first main surface 210a toward the core 3 is the upward direction. Note that when the shape of the bottom plate part 21 of the case 2 is a square, the length of the case 2 in the X direction and the length of the case 2 in the Y direction are the same.

[0038] Box portion 22 is attached to bottom plate portion 21 so as to cover inductor element L. That is, core 3 and coils 41, 42 are surrounded by box portion 22 and are not exposed to the outside. Therefore, inductor element L can be protected from the outside.

[0039] The first to fourth electrode terminals 51 to 54 are attached to the bottom plate portion 21. The first electrode terminal 51 and the second electrode terminal 52 are located at two corners of the bottom plate portion 21 facing each other in the Y direction, and the third electrode terminal 53 and the fourth electrode terminal 54 are located at two corners of the bottom plate portion 21 facing each other in the Y direction. The first electrode terminal 51 and the third electrode terminal 53 face each other in the X direction, and the second electrode terminal 52 and the fourth electrode terminal 54 face each other in the X direction.

[0040] The core 3 is a toroidal core, and the shape of the core 3 is an ellipse (track shape) when viewed from the central axis direction. When viewed from the central axis direction, the core 3 includes a pair of long side portions 31 extending along the long axis and facing each other in the short axis direction, and a pair of short side portions 32 extending along the short axis and facing each other in the long axis direction. The shape of the core 3 may be rectangular, elliptical, or circular when viewed from the central axis direction.

[0041] The core 3 is composed of, for example, a ceramic core such as ferrite, or a magnetic core made of iron-based powder molding or nanocrystalline foil. The core 3 has a first end face 301 and a second end face 302 that face each other in the central axis direction, an inner peripheral face 303, and an outer peripheral face 304. The first end face 301 is a lower end face of the core 3 and faces the first main surface 210a of the bottom plate portion 21. The second end face 302 is an upper end face of the core 3 and faces the inner surface of the box portion 22. The core 3 is stored in the case 2 so that the long axis direction of the core 3 coincides with the Y direction.

[0042] The shape of a cross section perpendicular to the circumferential direction as viewed from the central axis direction of core 3 is rectangular. First end face 301 and second end face 302 are disposed perpendicular to the central axis direction of core 3. Inner peripheral surface 303 and outer peripheral surface 304 are disposed parallel to the central axis direction of core 3. In this specification, "perpendicular" is not limited to a completely perpendicular state, but also includes a substantially perpendicular state. Furthermore, "parallel" is not limited to a completely parallel state, but also includes a substantially parallel state.

[0043] A lower portion of the core 3 is covered by the core cover 60. That is, a portion of the core 3 on the bottom plate portion 21 side is covered by the core cover 60. It is sufficient that at least a portion of the core 3 on the bottom plate portion 21 side is covered by the core cover 60, and the entire core 3 may be covered by the core cover 60. The core cover 60 is made of a super engineering plastic such as LCP, PPA, or PPS, which improves the heat resistance, insulation, and processability of the core cover 60.

[0044] The core cover 60 is formed in an annular shape and has an annular recess 61 that covers the lower part of the core 3. The core cover 60 can be attached to the core 3 by fitting the lower part of the core 3 into the annular recess 61 of the core cover 60.

[0045] Resin member 90 is disposed in recess 215 of bottom plate portion 21, and is in contact with bottom plate portion 21 and inductor element L. As a material for resin member 90, for example, a thermosetting epoxy resin can be used.

[0046] The first coil 41 is wound around the core 3 and the core cover 60 between the first electrode terminal 51 and the second electrode terminal 52. One end of the first coil 41 is connected to the first electrode terminal 51. The other end of the first coil 41 is connected to the second electrode terminal 52.

[0047] The second coil 42 is wound around the core 3 and the core cover 60 between the third electrode terminal 53 and the fourth electrode terminal 54. One end of the second coil 42 is connected to the third electrode terminal 53. The other end of the second coil 42 is connected to the fourth electrode terminal 54.

[0048] The first coil 41 and the second coil 42 are spirally wound around the core 3 along the circumferential direction of the core 3 as viewed from the central axis direction of the core 3. Specifically, the first coil 41 is wound around one longitudinal portion 31 of the core 3 along the longitudinal direction of the core 3, and the second coil 42 is wound around the other longitudinal portion 31 of the core 3 along the longitudinal direction of the core 3. The winding axis of the first coil 41 and the winding axis of the second coil 42 run parallel to each other. The first coil 41 and the second coil 42 are symmetrical with respect to the longitudinal axis of the core 3.

[0049] The number of turns of the first coil 41 is the same as the number of turns of the second coil 42. The winding direction of the first coil 41 about the core 3 is opposite to the winding direction of the second coil 42 about the core 3. In other words, the winding direction of the first coil 41 from the first electrode terminal 51 to the second electrode terminal 52 is opposite to the winding direction of the second coil 42 from the third electrode terminal 53 to the fourth electrode terminal 54.

[0050] A common mode current flows from the first electrode terminal 51 to the second electrode terminal 52 in the first coil 41, and flows from the third electrode terminal 53 to the fourth electrode terminal 54 in the second coil 42; that is, the first to fourth electrode terminals 51 to 54 are connected so that the current flows in the same direction. When a common mode current flows through the first coil 41, a first magnetic flux is generated in the core 3 by the first coil 41. When a common mode current flows through the second coil 42, a second magnetic flux is generated in the core 3 in a direction in which the first magnetic flux and the core 3 reinforce each other. Therefore, the first coil 41 and the core 3, and the second coil 42 and the core 3 act as inductance components, and noise is removed from the common mode current.

[0051] The first coil 41 is formed by connecting a plurality of pin members by welding such as laser welding or spot welding. Note that Fig. 3 does not show a state in which the plurality of pin members are actually welded, but shows a state in which the plurality of pin members are assembled.

[0052] The pin members are rod-shaped members, not printed wiring or conductive wires. The pin members have rigidity. Specifically, in a cross section perpendicular to the circumferential direction of the core 3, the length of the pin members is shorter than the length of one circumference of the core 3 passing through the first end face 301, the second end face 302, the inner circumferential face 303, and the outer circumferential face 304 of the core 3, and the rigidity itself is high, so that the pin members are difficult to bend.

[0053] The plurality of pin members include a bent pin member 410 bent into a substantially U-shape, a straight pin member 412 extending in a substantially straight line, and an endmost straight pin member 411.

[0054] The first coil 41 includes, in order from one end to the other end, an endmost straight pin member 411 on one end side (one side), a plurality of sets of bent pin members 410 and straight pin members 412, and an endmost straight pin member 411 on the other end side (the other side). The endmost straight pin member 411 is a straight pin member located at the end of the axial direction of the first coil 41. In this embodiment, the endmost straight pin member 411 and the straight pin member 412 have the same shape. However, this is not limited thereto, and the endmost straight pin member 411 and the straight pin member 412 may have different shapes. For example, the length of the endmost straight pin member 411 in the extension direction may be shorter than the length of the straight pin member 412 in the extension direction.

[0055] 5, when the folding pin member 410 is disposed along the second end face 302, the inner peripheral surface 303, and the outer peripheral surface 304 of the core 3, the spring index Ks of the folding pin member 410 is smaller than 3.6 at the radius of curvature R1 of the folding pin member 410 located at the corner of the outer peripheral surface 304 of the core 3 and the radius of curvature R2 of the folding pin member 410 located at the corner of the inner peripheral surface 303 of the core 3. The spring index Ks can be expressed as the radius of curvature R1, R2 of the folding pin member / the wire diameter r of the folding pin member. Thus, the folding pin member 410 has high rigidity and is difficult to bend.

[0056] The bent pin members 410 and the straight pin members 412 are alternately connected by welding, for example, laser welding or spot welding. One end of the straight pin member 412 is connected to one end of the bent pin member 410, and the other end of the straight pin member 412 is connected to one end of the other bent pin member 410. By repeating this, the multiple bent pin members 410 and the straight pin members 412 are connected, and the multiple connected bent pin members 410 and the straight pin members 412 are arranged in a spiral shape on the core 3. In other words, one set of bent pin members 410 and straight pin members 412 constitutes one turn.

[0057] The bent pin member 410 is arranged parallel to each of the second end face 302, the inner peripheral face 303, and the outer peripheral face 304 of the core 3. The bent pin member 410 is arranged so that a virtual line connecting both ends in the extension direction is perpendicular to the axial direction of the first coil 41. In other words, the bent pin member 410 is arranged so that a plane including the center line of the bent pin member 410 is parallel to a plane (XZ plane) perpendicular to the axial direction of the first coil 41. The straight pin member 412 is arranged parallel to the first end face 301 of the core 3. The straight pin member 412 extends in the X direction with a slight inclination in the Y direction. The most end straight pin member 411 is arranged parallel to the first end face 301 of the core 3. The most end straight pin member 411 extends in a direction parallel to the straight pin member 412.

[0058] The bent pin members 410 of adjacent turns are fixed to each other by an adhesive member 70. This allows the multiple bent pin members 410 to be stably attached to the core 3. Similarly, the adjacent endmost straight pin members 411 and straight pin members 412 are fixed to each other by an adhesive member 70, and the adjacent straight pin members 412 are fixed to each other by an adhesive member 70. This allows the multiple endmost straight pin members 411 and straight pin members 412 to be stably attached to the core 3.

[0059] The first electrode terminal 51 is connected to one of the endmost straight pin members 411, and the one endmost straight pin member 411 is connected to one end of the bent pin member 410 of the adjacent turn to the one endmost straight pin member 411. A part of the first electrode terminal 51 (a relay portion and a coil connection portion, which will be described later) enters the case 2, and the circumferential surface of the one endmost straight pin member 411 is connected to the first electrode terminal 51. Specifically, a part of the first electrode terminal 51 passes through the opening 216 and is connected to the circumferential surface of the one endmost straight pin member 411. In short, the first coil 41 and the first electrode terminal 51 are electrically connected via the opening 216.

[0060] The second electrode terminal 52 is connected to the other endmost straight pin member 411, and the other endmost straight pin member 411 is connected to one end of the bent pin member 410 of the adjacent turn to the other endmost straight pin member 411. A part of the second electrode terminal 52 (a relay portion and a coil connection portion, which will be described later) enters the case 2, and the circumferential surface of the other endmost straight pin member 411 is connected to the second electrode terminal 52. Specifically, a part of the second electrode terminal 52 passes through the opening 216 and is connected to the circumferential surface of the other endmost straight pin member 411. In short, the first coil 41 and the second electrode terminal 52 are electrically connected via the opening 216.

[0061] The second coil 42 is composed of a plurality of pin members, similar to the first coil 41. That is, the second coil 42 includes, in order from one end to the other end, an endmost straight pin member 421 on one end side (one side), a plurality of sets of bent pin members 420 and straight pin members 422, and an endmost straight pin member 421 on the other end side (the other side). The bent pin members 420 and straight pin members 422 are alternately connected and wound around the core 3. That is, the plurality of bent pin members 420 and straight pin members 422 are connected, and the connected plurality of bent pin members 420 and straight pin members 422 are wound around the core 3 in a spiral shape.

[0062] The third electrode terminal 53 is connected to one of the endmost straight pin members 421, and the one endmost straight pin member 421 is connected to one end of the bent pin member 420 of the adjacent turn to the one endmost straight pin member 421. A part of the third electrode terminal 53 (a relay portion and a coil connection portion, which will be described later) enters the case 2, and the circumferential surface of the one endmost straight pin member 421 is connected to the third electrode terminal 53. Specifically, a part of the third electrode terminal 53 passes through the opening 216 and is connected to the circumferential surface of the one endmost straight pin member 421. In short, the second coil 42 and the third electrode terminal 53 are electrically connected via the opening 216.

[0063] The fourth electrode terminal 54 is connected to the other endmost straight pin member 421, and the other endmost straight pin member 421 is connected to one end of the bent pin member 420 of the adjacent turn to the other endmost straight pin member 421. A part of the fourth electrode terminal 54 (a relay portion and a coil connection portion, which will be described later) enters the case 2, and the circumferential surface of the other endmost straight pin member 421 is connected to the fourth electrode terminal 54. Specifically, the fourth electrode terminal 54 passes through the opening 216 and is connected to the circumferential surface of the other endmost straight pin member 421. In short, the second coil 42 and the fourth electrode terminal 54 are electrically connected via the opening 216.

[0064] 3, the first coil 41 and the second coil 42 (pin members 410-412, 420-422) each include a conductor and a coating that covers a part of the conductor. The conductor is, for example, a copper wire, and the coating is, for example, a polyamideimide resin. The thickness of the coating is, for example, 0.02 to 0.04 mm.

[0065] The straight pin members 411 and 421 at the ends are made up of uncoated conductor portions 411a and 421a. The straight pin members 412 and 422 are made up of uncoated conductor portions 412a and 422a. The bent pin members 410 and 420 are made up of conductor portions 410a and 420a and coatings 410b and 420b.

[0066] At one end and the other end of the bent pin members 410, 420, the conductor parts 410a, 420a are exposed from the coatings 410b, 420b. That is, the endmost straight pin members 411, 421, the straight pin members 412, 422 and the bent pin members 410, 420 are welded to each other at the exposed conductor parts 411a, 421a, 412a, 422a, 410a, 420a. These conductor parts not covered with the coating, that is, the conductor parts exposed from the coating (without the coating), can be electrically connected to the outside.

[0067] 6 is an XZ cross-sectional view passing through the center of coil device 1 in the Y direction. Box portion 22 is omitted in FIG.

[0068] As shown in FIG. 6, in the first coil 41, the ends of adjacent pin members are welded together. The weld refers to a portion that melts once during welding and then solidifies. Specifically, the first coil 41 has a first weld w11 and a second weld w12. More specifically, in adjacent turns in the first coil 41, the straight pin member 412 and the bent pin member 410 of one turn form a first weld w11 in which one conductor portion 412a of the straight pin member 412 and the conductor portion 410a of the bent pin member 410 are welded together, and the straight pin member 412 and the bent pin member 410 of the other turn form a second weld w12 in which the other conductor portion 412a of the straight pin member 412 and the conductor portion 410a of the bent pin member are welded together.

[0069] 6 illustrates a turn of the first coil 41 composed of the straight pin member 412 and the bent pin member 410, the same applies to a turn composed of the endmost straight pin member 411 and the bent pin member 410. More specifically, the endmost straight pin member 411 is welded to the conductor portion 410a of the bent pin member 410 connected to the conductor portion 411a to form a first welded portion w11 or a second welded portion w12.

[0070] The second coil 42 has a first welded portion w21 and a second welded portion w22. In the second coil 42, similarly to the first coil 41, the straight pin member 422 and the bent pin member 420 of one turn are welded to one conductor portion 422a of the straight pin member 422 and the conductor portion 420a of the bent pin member 420 in adjacent turns to form a first welded portion w21, and the straight pin member 422 and the bent pin member 420 of the other turn are welded to the other conductor portion 422a of the straight pin member 422 and the conductor portion 420a of the bent pin member to form a second welded portion w22. In addition, the most end straight pin member 421 is welded to the conductor portion 420a of the bent pin member 420 connected to the conductor portion 421a to form the first welded portion w21 or the second welded portion w22. The first welded portion w21 and the second welded portion w22 of the second coil 42 have the same configuration as the first welded portion w11 and the second welded portion w12 of the first coil 41, and therefore a description thereof will be omitted.

[0071] The core cover 60 is disposed between the conductor portions and welded portions of the coils 41, 42 exposed from the coating and the core 3. This makes it possible to more reliably insulate the conductor portions and welded portions of the coils 41, 42 from the core 3.

[0072] The core cover 60 is provided over the first end face 301 of the core 3, a portion of the inner circumferential surface 303 of the core 3, and a portion of the outer circumferential surface 304 of the core 3. The core cover 60 has a first portion 60a facing the inner circumferential surface 303 of the core 3, a second portion 60b facing the outer circumferential surface 304 of the core 3, and a third portion 60c facing the first end face 301 of the core 3.

[0073] The core cover 60 is indirectly connected to the core 3. In other words, the core cover 60 is not directly connected to the core 3, and more specifically, the core cover 60 is connected to the core 3 via the core support member 80. By connecting the core support member 80 to a part of the core 3, the stress on the core 3 received from the core cover 60 can be reduced, and deterioration of the magnetic properties of the core 3 can be suppressed. In other words, a decrease in inductance value caused by magnetostriction can be suppressed. Note that the core cover 60 may not be connected to the core 3 via the core support member 80, and may simply be fitted into the core 3.

[0074] The core support member 80 is provided between the first end face 301 of the core 3 and the third portion 60c of the core cover 60. This makes it possible to reduce the effect of magnetostriction on the core 3 and ensure a stable attachment state of the core cover 60 to the core 3.

[0075] Soft resins such as urethane resin and silicon resin can be used as the material for the core support member 80. By providing such a soft resin, the influence of magnetostriction can be reduced.

[0076] 6, the core support member 80 is provided over the entire area between the first end face 301 of the core 3 and the third portion 60c of the core cover 60, but it may be provided only in a portion of the area. Also, in FIG. 6, the core support member 80 is provided between the first end face 301 of the core 3 and the third portion 60c of the core cover 60, but it may be provided between the inner circumferential surface 303 of the core 3 and the first portion 60a of the core cover 60, or between the outer circumferential surface 304 of the core 3 and the second portion 60b of the core cover 60, or may be provided in a plurality of these locations.

[0077] 6, the inductor element L is disposed in the recess 215 such that the conductor portions exposed from the coating of the coils 41, 42 are positioned on the first main surface 210a side. The resin member 90 is fixed in the recess 215 to fix the inductor element L to the bottom plate portion 21, and also covers at least a portion of the conductor portions exposed from the coating of the coils 41, 42. Preferably, the resin member 90 covers the entire conductor portions.

[0078] The resin member 90 is made of, for example, a thermosetting resin, and is fixed to the inductor element L and the bottom plate portion 21 by hardening. The resin member 90 contacts the inner surface of the recess 215, a part of the first portion 60a of the core cover 60, a part of the second portion 60b of the core cover 60, and a part of the third portion 60c of the core cover 60, and covers the conductor portions 411a, 412a, and 410a exposed from the coating 410b of the first coil 41 and the conductor portions 421a, 422a, and 420a exposed from the coating 420b of the second coil 42. Furthermore, the resin member 90 also covers the welded portions w11, w12, w21, and w22 of the coils 41 and 42.

[0079] Since the resin member 90 is fixed in the recess 215 of the bottom plate portion 21, the resin member 90 is stably fixed to the bottom plate portion 21, and the resin member 90 can stably fix the inductor element L to the bottom plate portion 21. Furthermore, when filling the recess 215 with the liquid resin member 90 in the manufacturing process of the coil component 1, the liquid resin member 90 can be retained in the recess 215, and the inductor element L can be reliably fixed to the bottom plate portion 21 by the resin member 90. Furthermore, the resin member 90 covers the conductor parts exposed from the coating of the coils 41 and 42, and therefore, defects such as electrical short circuits with the outside can be prevented. Furthermore, when the coil component 1 is subjected to an external force such as vibration or impact, the resin member 90 can absorb the impact and protect the coils 41 and 42.

[0080] (Details of electrode terminal configuration) Next, the detailed configuration of the electrode terminal will be described. Fig. 7 is a schematic plan view partially showing the second electrode terminal 52 before being connected to the first coil 41. That is, Fig. 7 shows the second electrode terminal 52 after the first coil 41 is assembled to the bottom plate portion 21 and before the first coil 41 and the second electrode terminal 52 are connected by, for example, welding. Fig. 8 is a cross-sectional view taken along line VIII-VIII in Fig. 7. Note that, although the second electrode terminal 52 will be described below, the configurations of the first electrode terminal 51, the third electrode terminal 53 and the fourth electrode terminal 54 are similar to the configuration of the second electrode terminal 52, and therefore detailed description thereof will be omitted.

[0081] As shown in FIG. 7 and FIG. 8, the second electrode terminal 52 is a plate-shaped terminal. The thickness of the second electrode terminal 52 is, for example, 0.3 mm. The second electrode terminal 52 has a coil connection portion 521 connected to the first end of the first coil 41, a mounting portion 522 mounted on a mounting board (not shown), a relay portion 523 connecting the coil connection portion 521 and the mounting portion 522, and a fillet portion 524 connected to the end of the mounting portion 522 opposite to the side to which the relay portion 523 is connected. When viewed from the Z direction, the coil connection portion 521 and the relay portion 523 extend from the mounting portion 522 in the reverse Y direction. The thickness direction of the coil connection portion 521 and the mounting portion 522 is parallel to the Z direction. The width direction, which is a direction perpendicular to the extension direction of the coil connection portion 521 and the relay portion 523, is parallel to the X direction.

[0082] The coil connection portion 521 is in the shape of a flat plate parallel to the XY plane. The coil connection portion 521 includes a first main surface 52s1, a second main surface 52s2 facing the first main surface 52s1, and a side surface 52s3 connecting the first main surface 52s1 and the second main surface 52s2. The coil connection portion 521 has a first recess C1 that opens to the first main surface 52s1, the second main surface 52s2, and the side surface 52s3, a wide portion 52W, and a narrow portion 52N. The first recess C1 is disposed between the wide portion 52W and the narrow portion 52N and adjacent to the wide portion 52W and the narrow portion 52N. That is, when viewed from a direction (Z direction) perpendicular to the first main surface 52s1, the coil connecting portion 521 is bifurcated at the tip side in the extending direction (Y direction) of the coil connecting portion 521 and the relay portion 523. In short, the second electrode terminal 52 is an open-ended terminal.

[0083] In this embodiment, when viewed from a direction perpendicular to the first main surface 52s1, the first recess C1 opens a part (tip surface) of the side surface 52s3 on the tip side in the extension direction of the coil connection part 521, the first main surface 52s1, and the second main surface 52s2. When viewed from a direction perpendicular to the first main surface 52s1, the first recess C1 is shaped to be part of an ellipse (track shape) whose major axis is parallel to the Y direction.

[0084] The wide portion 52W has a width in the X direction that is wider than the narrow portion 52N. The wide portion 52W is disposed closer to the extreme end of the first end of the first coil 41 than the narrow portion 52N. Specifically, the wide portion 52W is disposed closer to the side wall portion 211 of the bottom plate portion 21 than the narrow portion 52N in the X direction. This allows more generated heat to escape to the extreme straight pin member 411 side, for example, when the peripheral surface of the extreme straight pin member 411 of the first coil 41 and the second electrode terminal 52 are laser-welded. The narrow portion 52N has a width in the X direction that is narrower than the wide portion 52W. The narrow portion 52N is disposed closer to the center of the bottom plate portion 21 than the wide portion 52W in the X direction.

[0085] The maximum length L1 of the narrow portion 52N in the Y direction is preferably 50% or more of the maximum length L0 of the coil connection portion 521 in the Y direction. The distance L4 between the narrow portion 52N and the wide portion 52W (in other words, the width of the first recess C1 in the X direction) is preferably 20% or more of the maximum width W0 of the coil connection portion 521 in the X direction. By setting the maximum length L1 and the distance L4 as described above, a sufficiently wide area can be secured for providing a first connection member described later, and the connection stability between the first coil 41 and the second electrode terminal 52 can be improved. Specifically, for example, when the peripheral surface of the endmost straight pin member 411 of the first coil 41 and the second electrode terminal 52 are laser-welded, the above dimensional relationship can ensure a sufficient area of ​​the inner surface C1f of the first recess C1, and therefore a sufficiently wide area can be secured for laser irradiation.

[0086] The maximum width W1 in the X direction of the narrow portion 52N is smaller than the maximum width W2 in the X direction of the wide portion 52W. This makes the heat capacity of the narrow portion 52N smaller than the heat capacity of the wide portion 52W. For this reason, for example, when the peripheral surface of the endmost straight pin member 411 of the first coil 41 and the second electrode terminal 52 are laser-welded, when the second electrode terminal 52 is irradiated with a laser, the portion on the narrow portion 52N side, which has a smaller heat capacity, is more likely to melt. As a result, a large amount of heat is transferred to the endmost straight pin member 411 side, and the heat can be released to the endmost straight pin member 411 side, thereby reducing the thermal effect on the mounting portion 522.

[0087] The maximum length L2 of the wide portion 52W in the Y direction is shorter than the maximum length L1 of the narrow portion 52N in the Y direction. This can prevent the linear pin member 412 adjacent to the end straight pin member 411 from being short-circuited with the second electrode terminal 52. Specifically, as shown in FIG. 9 described later, even if the end straight pin member 411 and the linear pin member 412 extend in the X direction with a slight inclination to the Y direction, the distance between the wide portion 52W and the adjacent linear pin member 412 can be secured by making the maximum length L2 shorter than the maximum length L1. As a result, it is possible to prevent the wide portion 52W and the adjacent linear pin member 412 from being short-circuited.

[0088] An example of the above dimensions of the first recess C1, the wide portion 52W, and the narrow portion 52N is as follows. The maximum width W1 of the narrow portion 52N in the X direction is, for example, 0.65 mm. The maximum length L1 of the narrow portion 52N in the Y direction is, for example, 0.85 mm. The maximum width W2 of the wide portion 52W in the X direction is, for example, 0.85 mm. The maximum length L2 of the wide portion 52W in the Y direction is, for example, 0.65 mm. That is, the difference L3 between the maximum length L1 of the narrow portion 52N in the Y direction and the maximum length L2 of the wide portion 52W in the Y direction is, for example, 0.2 mm. The distance L4 between the narrow portion 52N and the wide portion 52W is, for example, 0.5 mm.

[0089] The mounting portion 522 is in the form of a flat plate parallel to the XY plane. The mounting portion 522 is embedded in the bottom portion 210 of the bottom plate portion 21 and fixed to the bottom plate portion 21. The mounting portion 522 is exposed from the bottom surface of the bottom plate portion 21 and is to be mounted on a mounting board. The mounting portion 522 is connected to the mounting board by, for example, reflow soldering. Preferably, the mounting portion 522 is Sn plated to ensure the wettability of the solder.

[0090] As shown in FIG. 8, the coil connection portion 521 and the mounting portion 522 are not on the same plane, and do not overlap when viewed from a direction (Z direction) perpendicular to the first main surface 52s1. Specifically, in this embodiment, the coil connection portion 521 is located above the mounting portion 522 in the Z direction. The coil connection portion 521 and the mounting portion 522 do not overlap when viewed from a direction perpendicular to the first main surface 52s1. The relay portion 523 is flat and is disposed at an angle with respect to the XY plane. One end of the relay portion 523 in the Y direction is connected to the coil connection portion 521, and the other end of the relay portion 523 in the Y direction is connected to the mounting portion 522. In short, the coil connection portion 521, the mounting portion 522, and the relay portion 523 are shaped like a flat plate folded twice. The shape of the relay portion 523 is not particularly limited, and may be a shape other than a flat plate.

[0091] According to the above configuration, the relay portion 523 and the coil connection portion 521 can be easily bent with the mounting portion 522 as a fulcrum, so that the second electrode terminal 52 can be given springiness in a direction perpendicular to the first main surface 52s1 of the coil connection portion 521. As a result, when the coil connection portion 521 and the first end portion of the first coil 41 are connected to each other, the coil connection portion 521 and the first end portion of the first coil 41 can be more reliably brought into contact with each other, so that the connection stability between the first coil 41 and the second electrode terminal 52 can be improved. In addition, even if an external impact is applied to the coil component 1, the springiness of the second electrode terminal 52 can reduce the stress applied to the first connection member 81, and the reliability of the coil component 1 can be improved.

[0092] The fillet portion 524 extends upward in the Z direction from an end of the mounting portion 522 on the opposite side to the side to which the relay portion 523 is connected. The fillet portion 524 is exposed to the outside of the coil component 1. The fillet portion 524 serves as a portion where the solder wets up. Therefore, when the coil component 1 is mounted on a mounting board via solder, the solder wets up the fillet portion 524, allowing visual confirmation after solder mounting and improving the connection strength of the solder. Preferably, the fillet portion 524 is Sn plated to ensure the wettability of the solder.

[0093] (Details of the connection between the coil and the electrode terminal) Next, a detailed configuration of the connection portion between the second electrode terminal 52 and the first coil 41 will be described. Fig. 9 is a schematic plan view partially showing the connection portion between the second electrode terminal 52 and the first coil 41. Fig. 10 is a cross-sectional view taken along line XX in Fig. 9. Note that Fig. 9 omits the bent pin member 410 connected to one end of the straight pin member 412. Also, Fig. 10 omits the cross-sectional hatching of the resin member 90 for ease of viewing.

[0094] As shown in FIG. 9 and FIG. 10, the first connection member 81 connects the peripheral surface 411ps of the first end 41e1 of the first coil 41 and the coil connection portion 521 of the second electrode terminal 52. The first connection member 81 is a welded portion, solder, or the like, formed by, for example, laser welding the first end 41e1 and the coil connection portion 521. The first connection member 81 is preferably a welded portion. This can increase the connection strength between the first coil 41 and the second electrode terminal 52. In addition, the electrical resistance between the first coil 41 and the second electrode terminal 52 can be reduced. This can reduce the electrical resistance of the coil component 1. In this embodiment, the first connection member 81 is a welded portion formed by laser welding the first end 41e1 and the coil connection portion 521. In addition, in this embodiment, the first end 41e1 is the entirety of the most-end straight pin member 411. In FIG. 9, for the sake of convenience, the inner surface of the first recess C1 that existed before welding is shown by a virtual line (two-dot chain line).

[0095] The first end 41e1 is arranged only on the first main surface 52s1 side of the coil connection portion 521, facing the first main surface 52s1, and is arranged so as to overlap with the first recess C1 when viewed from a direction perpendicular to the first main surface 52s1.

[0096] In a cross section perpendicular to the extending direction of the first end 41e1, the peripheral surface 411ps of the first end 41e1 has two flat surfaces 411fs facing each other in the Y direction, two flat surfaces 411fs facing each other in the Z direction, and a curved surface connecting the flat surfaces 411fs. That is, the cross-sectional shape of the first end 41e1 is substantially rectangular with rounded corners. The flat surface 411fs can be formed, for example, by crushing the peripheral surface of a pin member having a circular cross section. The flat surface 411fs faces the first main surface 52s1 and is arranged so as to overlap the first recess C1 when viewed from a direction perpendicular to the first main surface 52s1. The peripheral surface of the first end 41e1 does not have to have the flat surface 411fs. For example, the cross-sectional shape of the first end 41e1 may be circular.

[0097] At least a portion of the first connection member 81 is located in the first recess C1 and in contact with the inner surface C1f of the first recess C1. Specifically, a portion of the first connection member 81 is located in the first recess C1. In other words, a portion of the first connection member 81 is located in a region of the coil connection portion 521 that is more inward than the opening of the side surface 52s3 of the coil connection portion 521. A portion of the first connection member 81 is in contact with the inner surface C1f of the first recess C1.

[0098] Similarly, the second end of the first coil 41 is disposed only on the first main surface side of the coil connection portion of the first electrode terminal 51, facing the first main surface, and arranged so as to overlap with the first recess C1 when viewed from a direction perpendicular to the first main surface, and a part of the first connection member 81 is located within the first recess C1 and in contact with an inner surface C1f of the first recess C1. Also, the first end of the second coil 42 is disposed only on the first main surface side of the coil connection portion of the fourth electrode terminal 54, facing the first main surface, and arranged so as to overlap with the first recess C1 when viewed from a direction perpendicular to the first main surface, and a part of the first connection member 81 is located within the first recess C1 and in contact with an inner surface C1f of the first recess C1. In addition, the second end of the second coil 42 is positioned only on the first main surface side of the coil connection portion of the third electrode terminal 53, facing the first main surface, and is positioned so as to overlap with the first recess C1 when viewed in a direction perpendicular to the first main surface, and a portion of the first connection member 81 is located within the first recess C1 and is in contact with the inner surface C1f of the first recess C1.

[0099] According to the coil device 1, the first and second ends of the coils 41, 42 are connected to the first to fourth electrode terminals 51-54 such that the first and second ends are disposed only on the first main surface side of the coil connection portions of the first to fourth electrode terminals 51-54 and face the first main surface, and therefore the coils 41, 42 are not entangled and connected to the first to fourth electrode terminals 51-54. Here, "entangled" means that the coils 41, 42 are wound around the first to fourth electrode terminals 51-54.

[0100] Therefore, it is possible to prevent deformation of the first to fourth electrode terminals 51-54 caused by the operation of winding the coils 41, 42 or the residual stress of the wound coils 41, 42. This allows thick coils 41, 42 to be connected to thin first to fourth electrode terminals 51-54, and allows the use of first to fourth electrode terminals 51-54 that are easy to bend and coils 41, 42 that are compatible with large currents. In addition, because the coils 41, 42 are not wound around the first to fourth electrode terminals 51-54, bending bulges do not occur in the coils 41, 42, and therefore gaps are less likely to occur between the coils 41, 42 and the first to fourth electrode terminals 51-54, achieving stable connection and miniaturization.

[0101] Furthermore, since at least a portion of the first connection member 81 is located within the first recesses C1 of the first to fourth electrode terminals 51-54, the first connection member 81 can be observed from the second main surface side (the bottom plate portion 21 side of the case 2) of the coil connection portions of the first to fourth electrode terminals 51-54. This allows easy visual inspection of the connection states between the coils 41, 42 and the first to fourth electrode terminals 51-54.

[0102] Furthermore, according to the coil device 1, the peripheral surfaces of the endmost straight pin members 411, 421 face the first main surfaces of the coil connection portions of the first to fourth electrode terminals 51-54, so that it is easy to align the endmost straight pin members 411, 421 when connecting the first to fourth electrode terminals 51-54 to the endmost straight pin members 411, 421.

[0103] Furthermore, according to the coil component 1, the flat surfaces at the ends of the coils 41, 42 are connected to the first to fourth electrode terminals 51-54 via the first connecting member 81. This increases the contact area between the ends of the coils 41, 42 and the first to fourth electrode terminals 51-54, thereby improving the mechanical strength between the coils 41, 42 and the first to fourth electrode terminals 51-54. Furthermore, the cross-sectional area of ​​the electrical path between the coils 41, 42 and the first to fourth electrode terminals 51-54 increases, thereby reducing the electrical resistance of the coil component 1.

[0104] Furthermore, according to the coil device 1, the first coil 41 is spirally formed by alternately connecting a plurality of straight pin members 412 and a plurality of bent pin members 410, so that when winding the first coil 41 around the core 3, the first coil 41 can be wound in close proximity to the core 3. Similarly, the second coil 42 is spirally formed by alternately connecting a plurality of straight pin members 422 and a plurality of bent pin members 420, so that when winding the second coil 42 around the core 3, the second coil 42 can be wound in close proximity to the core 3.

[0105] Preferably, the first to fourth electrode terminals 51 to 54 are elastically deformable so that the coil connection portion can swing in a direction perpendicular to the first main surface. Specifically, in FIG. 8, the mounting portion 522 of the second electrode terminal 52 is fixed to the bottom plate portion 21, so that the second electrode terminal 52 is elastically deformable so that the coil connection portion 521 can swing in a direction perpendicular to the first main surface 52s1 with the mounting portion 522 as a fulcrum. The same is true for the other electrode terminals 51, 53, and 54. With this configuration, the connection stability between the coils 41 and 42 and the first to fourth electrode terminals 51 to 54 can be further improved. In addition, even if an external impact is applied to the coil component 1, the stress applied to the first connection member 81 can be further reduced, and the reliability of the coil component 1 can be further improved.

[0106] Preferably, the first main surface of the coil connection portion is located radially inward of the coils 41, 42 than the first main surface 210a of the bottom portion 210 of the bottom plate portion 21. Specifically, as shown in FIG. 10, the position P2 of the first main surface 52s1 of the coil connection portion 521 is located radially inward of the first coil 41 than the position P1 of the first main surface 210a of the bottom portion 210 of the bottom plate portion 21. In other words, in the Z direction, the position P2 of the first main surface 52s1 is located above the position P1 of the first main surface 210a. According to this configuration, the thickness of the resin member 90 arranged on the second main surface 52s2 side of the coil connection portion 521 can be made thicker than the thickness of the bottom portion 210 (i.e., the distance between the first main surface 210a and the second main surface 210b). This can reduce stress that may occur in the first connection member 81 due to external forces such as vibration and impact.

[0107] Preferably, when viewed from a direction perpendicular to the first main surface of the coil connection portion, the first connection member 81 does not have a portion that protrudes outward beyond the side surface of the coil connection portion. In other words, the first connection member 81 does not have a portion that protrudes outward beyond the opening in the side surface of the coil connection portion. With this configuration, the coil device 1 can be made smaller.

[0108] (Manufacturing method of coil parts) Next, a method for manufacturing the coil device 1 will be described.

[0109] The method for manufacturing the coil component 1 includes the steps of arranging the ends of the coils 41, 42 only on the first main surface side of the coil connection parts 511-541 of the first to fourth electrode terminals 51-54 so as to face the first main surface and overlap with the first recesses C1 provided in the first to fourth electrode terminals 51-54 when viewed from a direction perpendicular to the first main surface, and irradiating at least a part of the inner surface C1f of the first recess C1 with a laser from the second main surface side of the coil connection parts to form the first connection member 81. With this configuration, the coils 41, 42 can be connected to the first to fourth electrode terminals 51-54 without being entangled. Furthermore, the coil component 1 can be made smaller in size.

[0110] Specifically, as shown in FIG. 3, the first coil 41 and the second coil 42 are wound around the core 3 with the core cover 60 fitted in it so that their winding axes run parallel to each other, and at least a portion of the exposed conductor portions 411a, 412a, 410a of the first coil 41 and at least a portion of the exposed conductor portions 421a, 422a, 420a of the second coil 42 are positioned on the first end face 301 side of the core 3.

[0111] Thereafter, with the first end surface 301 of the core 3 facing upward, the pin members of the first coil 41 are welded, and then the pin members of the second coil 42 are welded.

[0112] Thereafter, the core 3 and the coils 41, 42 are disposed in the recess 215 of the bottom plate portion 21 so that the conductor portions exposed from the coating of the coils 41, 42 are positioned on the first main surface 210a side. At this time, for example, when connecting the first end portion 41e1 of the first coil 41 to the second electrode terminal 52, as shown in FIG. 11A, the peripheral surface of the first end portion 41e1 of the first coil 41 is disposed on the first main surface 52s1 side of the coil connection portion 521 of the second electrode terminal 52 so as to face the first main surface 52s1 and to overlap with the first recess C1 provided in the second electrode terminal 52 when viewed from a direction perpendicular to the first main surface 52s1. Then, the first end portion 41e1 of the first coil 41 is pressed against the coil connection portion 521 from the first main surface 52s1 side of the coil connection portion 521 to bring the first end portion 41e1 into contact with the coil connection portion 521.

[0113] The coil connection part 521, the mounting part 522 and the relay part 523 of the second electrode terminal 52 have a shape obtained by folding a flat plate twice, and therefore the springiness of the folded part allows the first end 41e1 to be more reliably contacted with the coil connection part 521. This ensures the connection stability between the first end 41e1 and the coil connection part 521. Similarly, the electrode terminals 51, 53 and 54 are also arranged such that the circumferential surface of the first end or the second end of the coils 41 and 42 is brought into contact with the coil connection part of the electrode terminals 51, 53 and 54. The most end straight pin members 411 and 421 may have height variations in the Z direction. The first to fourth electrode terminals 51 to 54 have springiness in the direction perpendicular to the first main surface of the coil connection part (Z direction), and therefore the height variations can be absorbed, and all the electrode terminals 51 to 54 can be more reliably connected to the ends of the coils 41 and 42.

[0114] Then, at least a part of the inner surface C1f of the first recess C1 is irradiated with a laser from the second main surface 52s2 side of the coil connection portion 521. At this time, the laser light is made to hit both the coil connection portion 521 and the first end portion 41e1. Specifically, since the spot diameter of the laser is small (for example, 0.05 mm), the laser is scanned along the inner surface C1f of the first recess C1 in the area LI surrounded by the dashed line in FIG. 11A. As a result, as shown in FIG. 11B, the first end portion 41e1 and the coil connection portion 521 are melted and then solidified to form the first connection member 81, and the first end portion 41e1 and the second electrode terminal 52 are connected. The same is true for the electrode terminals 51, 53, and 54, and the first end portion or the second end portion of the coils 41 and 42 are connected to the electrode terminals 51, 53, and 54.

[0115] As described above, since the first to fourth electrode terminals 51-54 have the first recess C1, it is possible to melt and weld both the coil connection portion and the first end of the coil by irradiating the laser to both the coil connection portion and the first end of the coil. On the other hand, if the first to fourth electrode terminals 51-54 do not have the first recess C1 and, for example, the center of the second main surface of the coil connection portion is irradiated with a laser for welding, the first end of the coil is not irradiated with the laser, resulting in poor connection stability.

[0116] 6, the liquid resin member 90 is filled into the recess 215 by, for example, a potting method. At this time, the liquid resin member 90 remains in the recess 215 and spreads onto the conductor parts exposed from the coating of the coils 41 and 42 and onto a part of the core cover 60. Furthermore, the liquid resin member 90 is also filled into the opening 216 of the bottom plate portion 21. In order to prevent the liquid resin member 90 from leaking from the opening 216, tape is attached to the second main surface 210b of the bottom portion 210 so as to close the opening 216.

[0117] Then, heat is applied to harden the liquid resin member 90. As a result, the core 3 and the coils 41, 42 can be fixed to the bottom plate portion 21 by the resin member 90, and the conductor portions of the coils 41, 42 exposed from the coating can be covered by the resin member 90. The opening 216 can also be filled with the resin member 90. A thermosetting epoxy resin is used as the material for the resin member 90, and the elastic modulus is 7 GPa. The hardening condition is heating at 120°C for 30 minutes.

[0118] Thereafter, the box portion 22 is placed over the coil component 1 and stored in the case 2 to complete the manufacture of the coil component 1. By using such a manufacturing method, the number of steps in the manufacture of the coil component 1 can be reduced, and the coil component 1 can be manufactured more easily.

[0119] Second embodiment Fig. 12 is a schematic cross-sectional view partially showing a coil component of the second embodiment. Fig. 12 corresponds to Fig. 10, and the side wall portion 211 side is omitted. In the second embodiment, the configuration of the first connecting member is different from that of the first embodiment. This difference will be described below. The other configurations are the same as those of the first embodiment, and the same reference numerals as those of the first embodiment are used, and the description thereof will be omitted.

[0120] 12, the first connection member 81A has a greater protruding height from the first main surface 52s1 of the coil connection portion 521 than the first connection member 81 of the first embodiment. As a result, in the Z direction, a position P3 of a portion of the circumferential surface of the first end portion 41e1 that faces the first main surface 52s1 is located higher than a position P2 of the first main surface 52s1. In other words, in the Z direction, the first end portion 41e1 (i.e., the endmost straight pin member 411) is located higher than the other straight pin members 412.

[0121] According to the above configuration, the thickness of the resin member 90 arranged on the second main surface 52s2 side of the coil connection portion 521 can be made thicker than the thickness of the bottom portion 210. This makes it possible to reduce stress that may be generated in the first connection member 81A due to an external force such as vibration or impact.

[0122] Note that, in the Z direction, the first main surface 52s1 of the coil connection portion 521 may be positioned in advance above a position where a portion of the circumferential surface of the straight pin member 412 facing the bottom 210 is disposed. Thereby, when the first coil 41 is assembled to the case 2, only the first end portion 41e1 (i.e., the endmost straight pin member 411) is pushed up in the Z direction by the spring property of the second electrode terminal 52, so that the first end portion 41e1 may be positioned above the other straight pin members 412.

[0123] Third embodiment 13 is a schematic plan view partially showing a coil component of the third embodiment. The third embodiment is different from the first embodiment mainly in the arrangement of the straight pin members and bent pin members, the shape of the electrode terminals, and the provision of a second connecting member. These main differences will be described below. The other configurations are the same as those of the first embodiment, and the same reference numerals as those of the first embodiment are used, and the description thereof will be omitted.

[0124] 13, the extension directions of the endmost straight pin member 411 and the straight pin member 412 are parallel to a direction perpendicular to the axial direction (Y direction) of the first coil 41. The bent pin member 410 extends in the X direction with an imaginary line connecting both ends in the extension direction slightly inclined toward the Y direction. In other words, the bent pin member 410 is disposed such that a plane including the center line of the bent pin member 410 is inclined with respect to a plane (XZ plane) perpendicular to the axial direction of the first coil 41.

[0125] The plurality of bent pin members 410 include an adjacent bent pin member 410aj connected adjacent to the endmost straight pin member 411. The end face 411ef of the end of the endmost straight pin member 411 and the adjacent bent pin member 410aj are connected to each other at the end face 411ef of the end of the endmost straight pin member 411 and the circumferential face 410ps of the end of the adjacent bent pin member 410aj. In this embodiment, the first end 41e1 of the first coil 41 is the endmost straight pin member 411 and the adjacent bent pin member 410aj.

[0126] In the first embodiment, the coil connection and relay portion of the first electrode terminal 51 are disposed closer to the center of the case 2 than the side wall portion 211 of the case 2 in the X direction, but in this embodiment, the coil connection and relay portion of the first electrode terminal 51B are disposed closer to the side wall portion 211 of the case 2 than the center of the case 2 in the X direction. Similarly, in the first embodiment, the coil connection and relay portion of the third electrode terminal 53 are disposed closer to the center of the case 2 than the side wall portion 211 of the case 2 in the X direction, but in this embodiment, the coil connection and relay portion of the third electrode terminal 53B are disposed closer to the side wall portion 211 of the case 2 than the center of the case 2 in the X direction. Note that, in the second electrode terminal 52 and the fourth electrode terminal 54, the coil connection and relay portion are disposed closer to the side wall portion 211 of the case 2 than the center of the case 2, as in the first embodiment. Since the coil connections and relay portions of all of the first to fourth electrode terminals are disposed closer to the side wall portion 211 of the case 2 than the center portion of the case 2, for example, the first electrode terminal and the fourth electrode terminal can be made common, and the second electrode terminal and the third electrode terminal can be made common. Therefore, according to the above configuration, the number of types of electrode terminals can be reduced compared to the first embodiment.

[0127] The coil connection portion 511B of the first electrode terminal 51B has a first recess C1 that opens to the first principal surface, the second principal surface 51s2, and the side surface 51s3 (not shown), a wide portion 51W, and a narrow portion 51N. That is, the coil connection portion 511B is bifurcated at the tip side in the Y direction when viewed from a direction perpendicular to the first principal surface. Furthermore, the coil connection portion 511B has a second recess C2 that opens to the first principal surface, the second principal surface 51s2, and the side surface 51s3. The second recess C2 is provided at a corner of the coil connection portion 511B and is disposed adjacent to the wide portion 51W.

[0128] In this embodiment, the maximum length of the wide portion 51W in the Y direction and the maximum length of the narrow portion 51N in the Y direction are the same. This allows the tip position of the wide portion 51W in the Y direction to be aligned with the tip position of the narrow portion 51N in the Y direction, so that it is possible to prevent the first electrode terminal 51B from being short-circuited with the straight pin member 412 adjacent to the end straight pin member 411. In addition, in this embodiment, the wide portion 51W is disposed at the connection portion between the end straight pin member 411 and the adjacent bent pin member 410aj. The narrow portion 51N is disposed so as to be closer to the end of the first end 41e1 of the first coil 41 than the wide portion 51W. This allows more generated heat to escape to the end straight pin member 411 side, for example, when the peripheral surface of the end straight pin member 411 of the first coil 41 and the first electrode terminal 51B are laser-welded.

[0129] The coil component 1B includes a second connection member 82 that connects the first end 41e1 of the first coil 41 and the first electrode terminal 51B. Like the first connection member 81, the second connection member 82 is a welded portion formed by, for example, laser welding the first end 41e1 and the coil connection portion 511B, solder, or the like. In this embodiment, the second connection member 82 is a welded portion formed by irradiating a laser along at least a portion of the inner surface of the second recess C2.

[0130] An end face 410ef of the adjacent bent pin member 410aj on the side where the most end straight pin member 411 is connected faces the first main surface of the coil connection portion 511B of the first electrode terminal 51B, and overlaps with an inner surface C2f of the second recess C2 when viewed from a direction perpendicular to the first main surface. At least a part of the second connection member 82 is located in the second recess C2 and contacts the inner surface C2f of the second recess C2. Thus, the second connection member 82 connects the first electrode terminal 51B and the end face 410ef of the adjacent bent pin member 410aj.

[0131] According to the above configuration, since the second connection member 82 is further provided, it is possible to further improve the mechanical strength between the first coil 41B and the first electrode terminal 51B. In addition, since the cross-sectional area of ​​the electrical path between the first coil 41B and the first electrode terminal 51B is increased, it is possible to further reduce the electrical resistance of the coil part 1B.

[0132] The third electrode terminal 53B may have a configuration similar to that of the first electrode terminal 51B. That is, the third electrode terminal 53B may have a second recess C2, at least a part of the second connection member 82 may be located in the second recess C2 and in contact with an inner surface C2f of the second recess C2, and the second connection member 82 may connect the third electrode terminal 53B and an end face of an adjacent bent pin member adjacent to the endmost straight pin member.

[0133] (Fourth embodiment) 14 is a schematic plan view partially showing a coil device according to the fourth embodiment. The fourth embodiment differs from the third embodiment in that one electrode terminal has a plurality of portions each consisting of a coil connection portion and a relay portion. This difference will be described below. The other configurations are the same as those of the third embodiment, and the same reference numerals as those of the third embodiment are used, and the description thereof will be omitted.

[0134] As shown in FIG. 14, in the first electrode terminal 51C of this embodiment, there are two portions (hereinafter, these portions are referred to as "projections") each consisting of a coil connection portion 511B and a relay portion 513 adjacent to each other in the X direction. One of the projecting portions (the projecting portion located on the reverse X direction side) is the same as the coil connection portion 511B and the relay portion 513 in the first electrode terminal 51B of the third embodiment. The other projecting portion (the projecting portion located on the forward X direction side) has the same shape as the one of the projecting portions. The coil connection portion 511B of the other projecting portion is connected to the peripheral surface of the endmost straight pin member 411 via the first connecting member 81.

[0135] According to the above configuration, the multiple first connection members 81 connect the first end 41e1 of the first coil 41B and the first electrode terminal 51C, which further improves the mechanical strength between the first coil 41B and the first electrode terminal 51C. In addition, the cross-sectional area of ​​the electrical path between the first coil 41B and the first electrode terminal 51C becomes larger, which further reduces the electrical resistance of the coil part 1B.

[0136] The third electrode terminal 53C may have a configuration similar to that of the first electrode terminal 51C. That is, the third electrode terminal 53C may have two protruding pieces adjacent to each other in the X direction, and the coil connection portion of one of the protruding pieces may be connected to the circumferential surface of the endmost straight pin member 421 and an end face of the adjacent bent pin member via the first connecting member 81 and the second connecting member 82, and the coil connection portion of the other protruding piece may be connected to the circumferential surface of the endmost straight pin member 421 via the first connecting member 81.

[0137] Fifth embodiment 15 is a schematic plan view partially showing a coil component of the fifth embodiment. The fifth embodiment differs from the third embodiment in that the most end straight pin member on one side in the axial direction of the coil is not provided. This difference will be described below. The other configurations are the same as those of the third embodiment, and the same reference numerals as those of the third embodiment are used and the description thereof will be omitted.

[0138] 15, the first end 41e1 of the first coil 41C is composed of a bent pin member 410, not a straight pin member. Specifically, the plurality of bent pin members 410 include an endmost bent pin member 4101 located at the end of at least one side in the axial direction of the first coil 41C. In the endmost bent pin member 4101, an end face 4101ef on the opposite side to the side to which the straight pin member 412 is connected faces a first main surface (not shown) of the coil connection portion 511B of the first electrode terminal 51B, and is disposed so as to overlap with the second recess C2 when viewed from a direction perpendicular to the first main surface.

[0139] The second connecting member 82 connects the coil connection portion 511B of the first electrode terminal 51B and the end face 4101ef of the outermost bent pin member 4101. In short, the coil component 1D of this embodiment is the coil component 1B of the third embodiment without the outermost straight pin member connected to the first electrode terminal. In this embodiment, the second recess C2 corresponds to the "first recess" in the claims, and the second connecting member 82 corresponds to the "first connecting member" in the claims.

[0140] According to the above configuration, since the most end bent pin member 4101 and the first electrode terminal 51B are connected along the extending direction of the most end bent pin member 4101, it is possible to smoothly pass a current through the first coil 41C. In addition, since the pin member located at the most end on one side of the axial direction of the first coil 41C is the bent pin member 410, the number of straight pin members can be reduced. In addition, the diameter of the bent pin member is usually larger than the diameter of the straight pin member. Therefore, when the end face of the bent pin member and the electrode terminal are welded by laser, for example, compared with the case where the peripheral surface of the straight pin member and the electrode terminal are welded by laser, for example. As a result, it is possible to improve the mechanical strength between the coil and the electrode terminal. In addition, since the cross-sectional area of ​​the electrical path between the coil and the electrode terminal is larger, it is possible to further reduce the electrical resistance of the coil component.

[0141] As in the case of the first electrode terminal side, the outermost straight pin member connected to the third electrode terminal may be omitted also in the case of the third electrode terminal side.

[0142] Sixth embodiment The sixth embodiment is mainly different from the first embodiment in that the first recess is not provided in the coil connection portion of the electrode terminal. This main difference will be described below. The other configurations are the same as those of the first embodiment, and detailed description thereof will be omitted.

[0143] As in the first embodiment, the electrode terminal includes a coil connection portion connected to an end of the coil, a mounting portion mounted on a mounting board, and a relay portion connecting the coil connection portion and the mounting portion. The coil connection portion includes a first main surface and a second main surface opposite the first main surface. The end of the coil is disposed only on the first main surface side of the coil connection portion and faces the first main surface. The coil connection portion and the mounting portion are not on the same plane and do not overlap when viewed from a direction perpendicular to the first main surface.

[0144] In this embodiment, the coil connection portion does not have a first recess. The position at which the first connection member is provided is not particularly limited, but for example, the first connection member may be provided in an area including a part of the side surface of the coil connection portion when viewed from a direction perpendicular to the first main surface of the coil connection portion. Also, the first connection member may be provided, for example, in the center of the second main surface of the coil connection portion.

[0145] According to the above configuration, the end of the coil and the electrode terminal are connected so that the end of the coil is disposed only on the first main surface side of the coil connection portion of the electrode terminal and faces the first main surface, so the coil is not wound around the electrode terminal. Therefore, it is possible to prevent deformation of the electrode terminal caused by the coil winding operation or residual stress of the wound coil. This allows a thick coil to be connected to a thin electrode terminal, and it is possible to use an electrode terminal that is easy to bend and a coil that is compatible with a large current. In addition, since the coil is not wound around the electrode terminal, bending bulge does not occur in the coil, and therefore gaps are less likely to occur between the coil and the electrode terminal, and connection stability and miniaturization can be achieved.

[0146] In addition, since the coil connection portion and the mounting portion are not on the same plane and do not overlap when viewed from a direction perpendicular to the first main surface of the coil connection portion, the relay portion and the coil connection portion are easily bent with the mounting portion as a fulcrum. This allows the electrode terminal to be given springiness in a direction perpendicular to the first main surface of the coil connection portion. As a result, when connecting the coil connection portion and the end of the coil, the coil connection portion and the end of the coil can be more reliably brought into contact with each other, thereby improving the connection stability between the coil and the electrode terminal. Furthermore, even if an external impact is applied to the coil component, the springiness of the electrode terminal can reduce the stress applied to the first connection member, thereby improving the reliability of the coil component.

[0147] The present disclosure is not limited to the above-described embodiments, and design modifications are possible without departing from the gist of the present disclosure. For example, the respective characteristic points of the first to sixth embodiments may be combined in various ways. The shape of the case and the shape of the core are not limited to the present embodiment, and design modifications are possible. The number of coils is not limited to the present embodiment, and design modifications are possible. The case box portion may not be provided, and the core cover may not be provided.

[0148] In the first to fifth embodiments, the electrode terminal has a wide portion and a narrow portion, but the shape of the electrode terminal is not particularly limited as long as it has a first recess. For example, the wide portion and the narrow portion may have the same maximum width. In the first to fifth embodiments, the first recess is shaped like a part of an oval, but the shape of the first recess is not particularly limited.

[0149] In the first to fifth embodiments, a part of the first connection member is located in the first recess and in contact with the inner surface of the first recess, but the entire first connection member may be located in the first recess and in contact with the inner surface of the first recess. In the third to fifth embodiments, a part of the second connection member is located in the second recess and in contact with the inner surface of the second recess, but the entire second connection member may be located in the second recess and in contact with the inner surface of the second recess.

[0150] This application claims priority based on Japanese Patent Application No. 2022-044129, filed in Japan on March 18, 2022, the entire contents of which are incorporated herein by reference. [Explanation of symbols]

[0151] 1. 1A~1D Coil parts 2 Cases 21 Bottom plate part 210 Bottom 210a First main surface 210b 2nd principal surface 211 Side wall 215 Recess 216 Opening 22 Hakobe 3 Cores 301 1st end surface (bottom surface) 302 Second end surface (top surface) 303 Inner peripheral surface 304 Outer surface 41, 41B, 41C First coil 41e1 1st end 410 Bent pin member 410aj Adjacent bent pin parts 410ef end face 410ps peripheral surface 410a Conductor part 410b Coating 4101 End bent pin member 4101ef end face 411 End straight pin member 411ef end face 411fs flat surface 411ps peripheral surface 412 Straight pin member 411a, 412a Conductor part 42 Second coil 420 Bent pin member 420a Conductor 420b coating 421 End straight pin member 422 Straight pin member 421a, 422a Conductor part 51~54 1st~4th electrode terminal 511B,521 Coil connection part 512,522 Mounting section 513,523 Relay section 524 Fillet 52s1 First main surface 51s2, 52s2 Second main surface 51s3,52s3 side 51N,52N Narrow part 51W, 52W wide section 60 Core Cover 81, 81A First connecting member 82 Second connecting member 90 Resin parts C1, C2 First and second recesses C1f, C2f inner surface L inductor element

Claims

1. A coil and A plate-shaped electrode terminal; a first connection member that connects a first end of the coil and the electrode terminal, the electrode terminal includes a coil connection portion connected to the first end of the coil, the coil connection portion includes a first main surface, a second main surface opposite to the first main surface, and a side surface connecting the first main surface and the second main surface, the coil connection portion has a first recess that opens to the first main surface, the second main surface, and the side surface, the first end of the coil is disposed only on the first main surface side of the coil connection portion, facing the first main surface, and overlapping with the first recess when viewed from a direction perpendicular to the first main surface; At least a portion of the first connection member is located within the first recess and in contact with an inner surface of the first recess.

2. The coil component according to claim 1 , wherein the first connection member is a welded portion formed by welding the first end of the coil and the coil connection portion of the electrode terminal.

3. a circumferential surface of the first end of the coil having a flat surface; The coil component according to claim 1 , wherein the flat surface faces the first main surface.

4. The coil includes a plurality of straight pin members and a plurality of bent pin members, the straight pin members and the bent pin members are alternately connected to form the spiral of the coil; the plurality of straight pin members includes an end straight pin member located at an end on at least one side of the coil in an axial direction, the first end of the coil includes the endmost straight pin member; a peripheral surface of the outermost straight pin member faces the first main surface and overlaps with the first recess when viewed in a direction perpendicular to the first main surface; The coil component according to claim 1 , wherein the first connection member connects the electrode terminal and the peripheral surface of the endmost straight pin member.

5. a second connection member that connects the first end of the coil and the electrode terminal; the coil connection portion has a second recess that opens to the first main surface, the second main surface, and the side surface, the plurality of bent pin members include adjacent bent pin members connected adjacent to the endmost straight pin member, The end straight pin member and the adjacent bent pin member are connected to each other at an end surface of the end of the end straight pin member and a peripheral surface of an end of the adjacent bent pin member, the first end of the coil further includes the adjacent folded pin member; an end surface of the adjacent bent pin member on a side to which the outermost straight pin member is connected faces the first main surface and overlaps an inner surface of the second recess when viewed from a direction perpendicular to the first main surface; At least a portion of the second connection member is located within the second recess and contacts an inner surface of the second recess; The coil component according to claim 4 , wherein the second connection member connects the electrode terminal and the end surface of the adjacent bent pin member.

6. The coil includes a plurality of straight pin members and a plurality of bent pin members, the straight pin members and the bent pin members are alternately connected to form the spiral of the coil; the plurality of bending pin members include an end bending pin member located at an end on at least one side of the coil in the axial direction, the first end of the coil includes the endmost bent pin member, an end surface of the outermost bent pin member opposite to the side to which the straight pin member is connected faces the first main surface and is disposed so as to overlap with the first recess when viewed from a direction perpendicular to the first main surface; The coil component according to claim 1 , wherein the first connection member connects the electrode terminal and the end face of the outermost bent pin member.

7. the electrode terminal further includes a mounting portion to be mounted on a mounting board, and a relay portion connecting the coil connection portion and the mounting portion, The coil component according to claim 1 , wherein the coil connection portion and the mounting portion are not on the same plane and do not overlap when viewed in a direction perpendicular to the first main surface.

8. The coil component according to claim 7 , wherein the electrode terminal is elastically deformable such that the coil connection portion is swingable in a direction perpendicular to the first main surface.

9. a step of disposing a first end of the coil only on a first main surface side of a coil connection portion of the electrode terminal, facing the first main surface, and overlapping a first recess provided in the electrode terminal when viewed from a direction perpendicular to the first main surface; forming a first connection member by irradiating at least a part of an inner surface of the first recess with a laser from a second main surface side of the coil connection portion; A method for manufacturing a coil component comprising:

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