Coil component

Abstract

To provide a coil component that can improve joint strength between an electrode and a wire extending from a winding core portion.SOLUTION: A coil component 100 includes: a core 10 including a winding core portion 11 extending in an axial direction and a first flange portion 12a and a second flange portion 12b provided on respective both end portions, in the axial direction, of the winding core portion 11; electrodes 20 including a first electrode 20a and a second electrode 20b provided on the first flange portion 12a and the second flange portion 12b, respectively; and a first wire 30 wound around the winding core portion 11 and including a first end portion 30a joined to the first electrode 20a and a second end portion 30b joined to the second electrode 20b. The first electrode 20a has a first joint surface 21a to which the first end portion 30a is joined, at least one protrusion 25 is provided on the first joint surface 21a, and the first end portion 30a is joined to the first joint surface 21a with the first wire 30 passing over the at least one protrusion 25 provided on the first joint surface 21a.SELECTED DRAWING: Figure 1

Description

[Technical field]

[0001] The present invention relates to a coil component. [Background technology]

[0002] Coil components are used, for example, to filter radiation noise from various electronic devices. Patent Document 1 discloses a coil component in which two wires are wound as a pair around a winding core of a ferrite core, and a locking portion consisting of a recess is provided on the winding core. By hooking the pair of wires on the locking portion of the winding core, the wires are prevented from shifting, and the occurrence of a gap between the pair of wires is prevented. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] JP 2007-208227 A Summary of the Invention [Problem to be solved by the invention]

[0004] However, the coil component of Patent Document 1 does not disclose anything about the bonding between the electrodes provided at both ends of the winding core and the wire. If the wire comes off the electrodes, the coil component cannot perform its original function and becomes a defective product. Therefore, there is a need to improve the bonding strength between the electrodes and the wire.

[0005] Therefore, a primary object of the present invention is to provide a coil component capable of improving the bonding strength between the electrodes and the wire extending from the winding core. [Means for solving the problem]

[0006] The coil component of the present invention is a coil component including: a core having a winding core portion extending in the axial direction and a first flange portion and a second flange portion provided at both axial ends of the winding core portion, respectively; electrodes including a first electrode and a second electrode provided at the first flange portion and the second flange portion, respectively; and a first wire wound around the winding core portion, and having a first end joined to the first electrode and a second end joined to the second electrode. The first electrode has a first bonding surface to which the first end is bonded. The first joining surface is provided with at least one protrusion. The first end of the first wire is joined to the first joint surface in a state where the first wire straddles at least one protrusion provided on the first joint surface.

[0007] Since the protrusion serves as an anchor for fastening the first end of the first wire to the first bonding surface, the first end of the first wire is less likely to come off the first electrode, thereby improving the bonding strength between the first electrode and the first end of the first wire. Effect of the Invention

[0008] According to the present invention, it is possible to provide a coil component capable of improving the bonding strength between the electrodes and the wire extending from the winding core portion.

[0009] The above and other objects, features and advantages of the present invention will become more apparent from the following detailed description of the preferred embodiments of the present invention, which proceeds with reference to the accompanying drawings. [Brief description of the drawings]

[0010] [Figure 1] 1 is an external perspective view showing an example of a coil component according to an embodiment of the present invention; [Diagram 2] FIG. 2 is a bottom view of FIG. [Diagram 3] FIG. 2 is a top view of FIG. [Figure 4] FIG. 2 is a side view of FIG. [Diagram 5] 3 is a cross-sectional view taken along line VV in FIG. 2. [Figure 6]6A and 6B are cross-sectional views taken along line VI-VI in FIG. 2, where (a) is a cross-sectional view showing the end of a wire having a rectangular cross-sectional shape, and (b) is a cross-sectional view showing the end of a wire having a cross-sectional shape with different thicknesses in different parts. [Figure 7] FIG. 13 is an enlarged bottom view showing another embodiment 1 of the arrangement positions of the protrusions. [Figure 8] FIG. 11 is an enlarged bottom view showing another embodiment 2 of the arrangement positions of the protrusions. [Figure 9] FIG. 11 is an enlarged bottom view showing another embodiment 3 of the arrangement positions of the protrusions. [Figure 10] 3A and 3B are cross-sectional views corresponding to line VV in FIG. 2 showing another embodiment 1 of the protrusion shape, where (a) is a cross-sectional view of the shape of the protrusion at the end portion on the first winding core side, and (b) is a cross-sectional view of the shape of the protrusion at the end portion opposite the first winding core side. [Figure 11] FIG. 11 is an external perspective view showing an example of a coil component according to a modified example of the present invention. [Figure 12] FIG. 11 is a bottom view showing an example of a coil component according to another modified example of the present invention. [Figure 13] 3 is a cross-sectional view taken along line VV in FIG. 2 of a coil component having an electrode using a coated electrode. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0011] 1. Coil parts A coil component according to an embodiment of the present invention will be described. FIG. 1 is an external perspective view showing an example of a coil component according to an embodiment of the present invention. FIG. 2 is a bottom view of FIG. 1. FIG. 3 is a top view of FIG. 1. FIG. 4 is a side view of FIG. 1. FIG. 5 is a cross-sectional view taken along line VV in FIG. 2. In FIG. 5, the winding core portion 11 is removed, and the first flange portion 12a, the protrusion 25, the first end portion 30a, and the like are simplified to be shown. FIG. 6 is a cross-sectional view taken along line VI-VI in FIG. 2, where (a) is a cross-sectional view showing an end portion of a wire having a rectangular cross-sectional shape, and (b) is a cross-sectional view showing an end portion of a wire having a cross-sectional shape with thicknesses varying depending on portions.

[0012] The coil component 100 includes a core 10, an electrode 20, and a wire 30. In this embodiment, a common mode choke coil will be described as an example of the coil component 100. However, the coil component is not limited to a common mode choke coil, and may be, for example, a wound coil such as a transformer or a coupled inductor. Each part will be described below.

[0013] Core 10 has a winding core portion 11 and a pair of flange portions 12. Here, in Figures 1 to 4 and the like, the direction in which the pair of flange portions 12 face each other is the L direction, which is the length direction of core 10. With the surface of flange portion 12 of core 10 on which electrode 20 is arranged as the bottom surface, the direction perpendicular to the L direction in the bottom surface direction is the W direction, which is the width direction of core 10. The direction perpendicular to the L direction and W direction is the T direction, which is the height direction of core 10.

[0014] The winding core 11 extends in the axial direction (here, the L direction). The wire 30 is wound around the winding core 11. The pair of flanges 12 has a first flange 12a and a second flange 12b provided on both ends of the winding core 11 in the axial direction. An electrode 20 to which both ends of the wire 30 are connected is disposed on each of the first flange 12a and the second flange 12b.

[0015] The first flange 12a and the second flange 12b are formed to be slightly larger than the winding core 11. The first flange 12a is disposed at one of both ends of the winding core 11 so as to protrude from the winding core 11 in a direction perpendicular to the axial direction. In the example of FIG. 1 etc., the first flange 12a is formed in a rectangular parallelepiped shape and has a first bottom surface 12a1 on which a first electrode 20a described later is disposed, a first upper surface 12a2 facing the first bottom surface 12a1, and a pair of first side surfaces 12a3 connecting the first bottom surface 12a1 and the first upper surface 12a2. The first flange 12a has an inner surface facing the winding core 11 side and an outer surface facing the opposite side to the winding core 11.

[0016] The second flange portion 12b is disposed so as to protrude from the winding core portion 11 in a direction perpendicular to the axial direction at the other of both ends of the winding core portion 11. In the example of FIG. 1 etc., the second flange portion 12b has the same shape as the first flange portion 12a. The second flange portion 12b is formed in a rectangular parallelepiped shape and has a second bottom surface 12b1 on which a second electrode 20b described later is disposed, a second upper surface 12b2 facing the second bottom surface 12b1, and a pair of second side surfaces 12b3 connecting the second bottom surface 12b1 and the second upper surface 12b2. The second flange portion 12b has an inner surface facing the winding core portion 11 side and an outer surface facing the opposite side to the winding core portion 11.

[0017] 1 and the like, each of the winding core 11 and the pair of flanges 12 is rectangular parallelepiped shaped. However, the shapes of the winding core 11 and the pair of flanges 12 are not limited to this, and may be, for example, cylindrical, elliptical, cubic, or polygonal. The core 10 may be made of a magnetic material such as ferrite or an amorphous alloy, or may be made of a non-magnetic material such as alumina or resin.

[0018] In this embodiment, the wire 30 is composed of one piece. The wire in the example of FIG. 1 is hereinafter referred to as the first wire 30 (one example of a wire). The first wire 30 is wound around the winding core portion 11 of the core 10. The first wire 30 is composed of a conductor wire made of a conductive material arranged inside and covered with a covering material which is an insulating material. The conductor wire is made of, for example, copper, silver, gold, etc. Also, the conductor wire is formed in, for example, a thin cylindrical shape. However, the conductor wire may be formed in a plate shape having a width. The covering material is made of, for example, enamel resin, polyurethane resin, polyamideimide resin, etc. The first wire 30 has both ends. The first end 30a which is one end of the first wire 30 is joined to the first electrode 20a. The second end 30b which is the other end of the first wire 30 is joined to the second electrode 20b. The number of wires is not limited to one.

[0019] The electrode 20 has a first electrode 20a to which the first end 30a is joined, and a second electrode 20b to which the second end 30b is joined. The first electrode 20a is provided on the first flange 12a, and the second electrode 20b is provided on the second flange 12b. The first electrode 20a may be disposed at one end of the first bottom surface 12a1 in the W direction in the first flange 12a, or at the other end of the first bottom surface 12a1 in the W direction, or may be disposed near the center. The first electrode 20a may be disposed so as to cover the entire surface of the first bottom surface 12a1 in the first flange 12a. In this embodiment, the first electrode 20a is disposed at one end of the first bottom surface 12a1 in the W direction in the first flange 12a. The second electrode 20b may be disposed at one end of the second bottom surface 12b1 in the W direction in the second flange portion 12b, at the other end of the second bottom surface 12b1 in the W direction, or near the center. The second electrode 20b may be disposed so as to cover the entire surface of the second bottom surface 12b1 in the second flange portion 12b. In this embodiment, the second electrode 20b is disposed at one end of the second bottom surface 12b1 in the W direction in the second flange portion 12b. That is, in this embodiment, the first electrode 20a and the second electrode 20b are disposed on the same side of the winding core portion 11 in the bottom surface direction.

[0020] In this embodiment, the first and second electrodes 20a, 20b are made of metal plates. The first and second electrodes 20a, 20b have a joint surface 21 to which the first end 30a and the second end 30b of the first wire 30 are joined. Specifically, the first electrode 20a on the first bottom surface 12a1 has a first joint surface 21a to which the first electrode 20a and the first end 30a are joined. The second electrode 20b on the second bottom surface 12b1 has a second joint surface 21b to which the second electrode 20b and the second end 30b are joined. The first and second joint surfaces 21a, 21b are the upper surfaces of the first and second electrodes 20a, 20b when the first and second bottom surfaces 12a1, 12b1 of the first and second flanges 12a, 12b face upward in FIG. 1.

[0021] The first and second electrodes 20a, 20b are bonded to the first and second bottom surfaces 12a1, 12b1 by an adhesive such as, but not limited to, epoxy resin. The first and second electrodes 20a, 20b are formed of a metal such as Cu, Ag, Au, or Fe, and the bonding surface 21 is plated with Sn plating, Ni plating, or a two-layer plating of Sn and Ni plating.

[0022] The ends 30a, 30b of the first wire 30 are joined to the electrode 20 by laser welding, thermocompression bonding, etc. During laser welding, thermocompression bonding, etc., the coating material of the ends 30a, 30b of the first wire 30 is removed, and the electrode 20 and the conductors of the ends 30a, 30b of the first wire 30 are thermally welded. An alloy layer is formed at the joint 27 between the electrode 20 and the conductors of the ends 30a, 30b of the first wire 30. For example, when the conductor of the first wire 30 contains Cu and the electrode 20 contains Sn and Ni, the Cu of the first wire 30 and the Sn and Ni of the electrode 20 are mutually diffused between the conductor and the electrode 20 by laser welding, thermocompression bonding, etc. As a result, an alloy layer containing Cu and at least one of Sn and Ni is formed. The alloy layer has a state in which the gap between the first wire 30 and the electrode 20 disappears due to interdiffusion and different metals are mixed, so that the bonding strength between the end of the first wire 30 and the electrode 20 can be relatively large. The first electrode 20a and the first end 30a are bonded by a first bonding portion 27a made of an alloy layer. The second electrode 20b and the second end 30b are bonded by a second bonding portion 27b made of an alloy layer.

[0023] In addition, the joint surface 21 has at least one protrusion 25 protruding from the flat portion of the joint surface 21. The protrusion 25 also functions as the electrode 20 and is a part of the electrode 20. At the joint 27 between the electrode 20 and the end of the first wire 30, the end of the first wire 30 is joined to the joint surface 21 in a state where the first wire 30 straddles at least one protrusion 25 provided on the joint surface 21, for example, in a state where the first wire 30 is caught on the protrusion 25. At this time, the end of the first wire 30 contacts the protrusion 25 directly or via the joint 27. As described above, the end of the first wire 30 is integrated with the electrode 20 and becomes an alloy layer at the joint 27. However, a part of the end of the first wire 30 may remain in a conductive wire state. Therefore, the end of the first wire 30 being joined to the joining surface 21 in a state where the first wire 30 straddles the protrusion 25 of the joining surface 21 can be considered to mean a case where the end of the first wire 30 is joined to the joining surface 21 in a state where an alloy layer consisting of the end of the first wire 30 and the electrode 20 straddles the protrusion 25, a case where the end of the first wire 30 in a conductor state is joined to the joining surface 21 in a state where the end of the first wire 30 straddles the protrusion 25, and a case where the end of the first wire 30 is joined to the joining surface 21 in a state where both the alloy layer and the end of the first wire 30 in a conductor state straddle the protrusion 25. In the present disclosure, in any case, it is defined as "both ends of the first wire 30 are joined to the protrusion 25."

[0024] Specifically, at least one protrusion 25 is formed on at least one of the first bonding surface 21a and the second bonding surface 21b. In this embodiment, the protrusion 25 is provided on the first bonding surface 21a. Then, the first end 30a of the first wire 30 is bonded to the first bonding surface 21a at a first bonding portion 27a between the first electrode 20a and the first end 30a of the first wire 30, with the first wire 30 straddling at least one protrusion 25 provided on the first bonding surface 21a. At this time, the first end 30a of the first wire 30 contacts the protrusion 25 directly or via the first bonding portion 27a. Furthermore, the protrusion 25 is provided on the second bonding surface 21b. The second end 30b of the first wire 30 is joined to the second joint surface 21b at a second joint portion 27b between the second electrode 20b and the second end 30b of the first wire 30, with the first wire 30 straddling at least one protrusion 25 provided on the second joint surface 21b. At this time, the second end 30b of the first wire 30 contacts the protrusion 25 directly or via the second joint portion 27b. Note that the protrusion 25 may be provided on either one of the first and second joint surfaces 21a and 21b, and either one of the first and second ends 30a and 30b may be joined to either one of the first and second joint surfaces 21a and 21b at either one of the first and second joint portions 27a and 27b, with the first wire 30 straddling the protrusion 25.

[0025] As shown in FIG. 4, FIG. 5, etc., it is preferable that the protrusion 25 is embedded in at least one of the first and second ends 30a, 30b at at least one of the first and second joints 27a, 27b, so that the end of the first wire 30 is joined to the joint surface 21. The state in which the protrusion 25 is embedded in the first and second ends 30a, 30b includes any of the following states: the protrusion 25 is embedded in the alloy layer, the protrusion 25 is embedded in the end of the first wire 30 in a conductor state, and the protrusion 25 is embedded in both the alloy layer and the end of the first wire 30 in a conductor state. Since the protrusion 25 of the electrode 20 is embedded in the end of the first wire 30, the force of the protrusion 25 as an anchor to hold the first wire 30 to the joint surface 21 is increased. Therefore, the joint strength between the electrode 20 and the first wire 30 can be further improved.

[0026] In the present embodiment, the protrusion 25 is provided at the winding core side end 22, which is the end of the joint surface 21 on the winding core 11 side. The winding core side end 22 is along the end face of the electrode 20 on the winding core 11 side, extending in the W direction. The protrusion 25 is formed long along the winding core side end 22 within the joint surface 21.

[0027] The protrusion 25 is provided along the first winding core portion side end 22a, which is the end of the first joint surface 21a on the winding core portion 11 side. The protrusion 25 is provided along the second winding core portion side end 22b, which is the end of the second joint surface 21b on the winding core portion 11 side. When the protrusion 25 is provided on either one of the first and second joint surfaces 21a, 21b, it is sufficient that the protrusion 25 is provided on either the first winding core portion side end 22a of the first joint surface 21a or the second winding core portion side end 22b of the second joint surface 21b.

[0028] Moreover, the first wire 30 can be configured such that, near the end or start of winding, a separated portion 31 separated from the winding core portion 11 and an end portion of the first wire 30 face each other across the winding core portion 11. A protrusion 25 is provided on the joint surface 21 of the electrode 20.

[0029] 1, in the present embodiment, the turn of the first wire 30 located closest to the first flange 12a is arranged such that a first separated portion 31a separated from the winding core 11 and a first end portion 30a face each other across the winding core 11. Between the first separated portion 31a and the first electrode 20a, the first wire 30 is separated from the winding core 11 and passes through the air in a non-contact state. Hereinafter, this non-contact portion will be referred to as an aerial wiring portion.

[0030] In the example of FIG. 1, the second end 30b and the second separated portion 31b, where the turn of the first wire 30 closest to the second flange portion 12b is separated from the winding core portion 11, are located on the same side of the winding core portion 11. In the example of FIG. 1, a protrusion 25 is provided on the second joint surface 21b of the second electrode 20b. However, the protrusion 25 does not have to be provided on the second joint surface 21b. Between the second separated portion 31b and the second electrode 20b, the first wire 30 is separated from the winding core portion 11 and passes through the air in a non-contact state. Hereinafter, this non-contact portion will be referred to as an aerial wiring portion.

[0031] The protrusions 25 can be formed by, for example, pressing a metal mold having a protrusion against the electrode 20, thereby deforming the electrode 20 to correspond to the protrusion of the metal mold. Also, on the surface opposite the protrusions 25, recesses 251 (FIG. 5) are formed by the electrode 20 being pressed by the protrusion of the metal mold. The recesses 251 may contain air or may be filled with an adhesive. As another method of formation, a die can be pressed against the joining surface 21 other than the projections 25 to make a depression, thereby making the portions that will become the projections 25 rise relatively to form the projections 25.

[0032] Next, the cross-sectional shape of the end of the first wire 30 bonded onto the bonding surface 21 will be described. Here, the second end 30b of the first wire 30 will be described, but the first end 30a is similar. FIG. 6 shows a cross section taken along line VI-VI in FIG. 2. The cross-sectional shape of the second end 30b may be rectangular as shown in (a), or may have a thickness that varies depending on the part as shown in (b). The second end 30b may have only a rectangular cross-sectional shape, may have only a cross-sectional shape that varies in thickness depending on the part, or may have a mixture of these.

[0033] 6(a), the second electrode 20b is provided on the second bottom surface 12b1 of the second flange portion 12b. The second end portion 30b of the first wire 30 is joined to the second electrode 20b by the second joint portion 27b on the second joint surface 21b of the second electrode 20b. In the example of FIG. 6(a), the cross-sectional shape of the second end portion 30b at the second joint portion 27b is rectangular. Although the cross-sectional shape of the second end portion 30b has been described as rectangular here, it may be square.

[0034] 6(b), unlike FIG. 6(a), the cross-sectional shape of the second end 30b at the second joint 27b is different on the left and right. In the example of FIG. 6(b), the thickness of the second end 30b gradually decreases from the winding core 11 toward the opposite side along the axial direction of the winding core 11.

[0035] The height of the projection 25 from the joint surface 21 is such that the projection 25 bites into the end of the first wire 30 but the end of the first wire 30 is not cut off. For example, it is preferable that the height of the projection 25 from the joint surface 21 does not exceed the height of the first wire 30 from the joint surface 21. Alternatively, it is preferable that the height of the projection 25 does not exceed the height of the joint 27. Also, with reference to FIG. 5, it is preferable that the height h1 of the projection 25 (protruding height from the first joint surface 21a) is 1 / 10 or more and 1 / 4 or less of the wire diameter r (diameter r of the conductor) of the first wire 30. This makes it possible to suppress damage such as breakage of the first wire 30 due to the projection 25 biting too much into the first wire 30. Also, the bite depth h2 of the projection 25 into the first wire 30 (the distance from the surface of the conductor that the projection 25 bites into the inside of the conductor) is such that the end of the first wire 30 is not cut off.

[0036] 2. Effects (1) According to the above embodiment, the joint surface 21 (first and second joint surfaces 21a, 21b) between the electrode 20 (first and second electrodes 20a, 20b) and the end of the first wire 30 (first and second end portions 30a, 30b) is provided with the protrusions 25, and the end of the first wire 30 is joined to the joint surface 21 of the electrode 20 with the first wire 30 straddling the protrusions 25. Therefore, the protrusions 25 serve as anchors that fasten the end of the first wire 30 to the joint surface 21, so that the end of the first wire 30 is less likely to come off from the electrode 20. This can improve the joint strength between the electrode 20 and the end of the first wire 30. For example, if the joint surface 21 is flat and the end of the first wire 30 is less likely to get caught in the electrode 20, the end of the first wire 30 is likely to come off from the electrode 20. However, with the above configuration, the protrusions 25 can improve the joint strength between the electrode 20 and the end of the first wire 30.

[0037] Here, the first wire 30 is wound around the winding core 11, and tension is generated in the first wire 30 from its end toward the winding core 11. This tension changes, for example, due to temperature changes in the atmosphere in which the coil device 100 is placed. If a large tension is generated from the end of the first wire 30 toward the winding core 11 due to such a change in tension, the end of the first wire 30 may be pulled away from the electrode 20. However, as described above, the protrusion 25 can fasten the end of the first wire 30 to the electrode 20, and the bonding strength between the electrode 20 and the end of the first wire 30 can be improved.

[0038] (2) According to the above embodiment, the protrusion 25 is provided on the winding core portion side end 22 close to the winding core portion 11 side on the joint surface 21. Here, the first wire 30 is wound around the winding core portion 11, and tension is generated in the first wire 30 from the end toward the winding core portion 11. When the end of the first wire 30 is pulled toward the winding core portion 11 in this manner, the protrusion 25 of the winding core portion side end 22 serves as an anchor that efficiently fastens the first wire 30 to the joint surface 21. In other words, the tension applied to the end of the first wire 30 toward the winding core portion 11 can be received by the protrusion 25 of the winding core portion side end 22 on the winding core portion 11 side on the joint surface 21, that is, on the side of the end of the first wire 30 on the joint surface 21 that is closer to the winding core portion 11. In particular, when the first wire 30 is pulled from the joint surface 21 toward the surface of the winding core 11 with the joint surface 21 positioned higher than the surface of the winding core 11, the tension of the end of the first wire 30 acts largely on the corner of the joint surface 21 close to the winding core side end 22. The tension applied to the end of the first wire 30 at this corner can be efficiently received by the protrusion 25 of the winding core side end 22. This makes it possible to further improve the bonding strength between the electrode 20 and the end of the first wire 30. Furthermore, even if the first wire 30 does not extend to the winding core opposite end 23 opposite the winding core side end 22, the protrusion 25 of the winding core side end 22 can reliably secure the end of the first wire 30 to the joint surface 21.

[0039] (3) According to the above embodiment, the projection 25 is formed long along the winding core portion side end 22 within the joint surface 21. When the projection 25 is formed long in this manner, the contact area between the projection 25 and the end of the first wire 30 is increased, and the end of the first wire 30 can be reliably joined to the joint surface 21 with the first wire 30 straddling the projection 25. This makes it possible to further improve the joint strength between the electrode 20 and the end of the first wire 30. Furthermore, even if the joining position of the first wire 30 is misaligned, the end of the first wire 30 can be reliably joined to the joining surface 21 so as to straddle the projection 25 .

[0040] (4) According to the above embodiment, the first separated portion 31a and the first end 30a of the first wire 30 face each other with the winding core 11 in between. When the first separated portion 31a and the first end 30a face each other with the winding core 11 in between, the aerial wiring portion is longer than when the first separated portion 31a and the first end 30a are on the same side of the winding core 11. When the aerial wiring portion is long, the tension from the first end 30a to the winding core 11 tends to be larger than when the aerial wiring portion is short. Even when the tension is large, the first electrode 20a facing the first separated portion 31a with the winding core 11 in between has the protrusion 25, and the protrusion 25 of the first electrode 20a serves as an anchor for fastening the first end 30a to the first joint surface 21a. This makes it possible to improve the joint strength between the first electrode 20a and the first end 30a of the first wire 30.

[0041] According to the above embodiment, the second separated portion 31b and the second end 30b of the first wire 30 are located on the same side with respect to the winding core 11. When the second separated portion 31b and the second end 30b are located on the same side with respect to the winding core 11 in this manner, the aerial wiring portion is shorter than when the second separated portion 31b and the second end 30b are on opposite sides with respect to the winding core 11. When the aerial wiring portion is short, the tension from the second end 30b toward the winding core 11 tends to be smaller than when the aerial wiring portion is long. Even in this case, if the protrusion 25 is provided on the second joint surface 21b, the joint strength between the second electrode 20b and the second end 30b can be further improved.

[0042] (5) In the above embodiment, as shown in FIG. 6(b), the thickness of the second end 30b (first end 30a) on the winding core 11 side is greater than the thickness of the opposite side of the winding core 11. The reason why the thickness of the second end 30b (first end 30a) differs depending on the position is considered to be due to differences in the shape of the electrode 20, the inclination of the electrode 20, the pressing force when the second end 30b (first end 30a) is joined to the electrode 20, and the like. This difference in thickness causes a difference in the joining strength of the second end 30b (first end 30a) to the electrode 20. For example, the part of the second end 30b (first end 30a) that is thicker on the winding core 11 side is a part where the pressing force during joining is weak, and the joining strength between the second end 30b (first end 30a) and the electrode 20 may be weakened. Even in such a case, particularly when the protrusion 25 is provided at the winding core portion side end 22, the second end 30b (first end 30a) can be joined to the second joint surface 21b (first joint surface 21a) in a state in which the thicker portion on the winding core portion 11 side of the second end 30b (first end 30a) straddles the protrusion 25 of the winding core portion side end 22. Thus, the joint strength between the second end 30b (first end 30a) and the electrode 20 can be improved.

[0043] As described above, the embodiment of the present invention has been disclosed in the above description, but the present invention is not limited thereto. In other words, various modifications can be made to the above-described embodiments in terms of mechanism, shape, material, quantity, position, arrangement, etc. without departing from the scope of the technical idea and purpose of the present invention, and these are included in the present invention.

[0044] 3. Variations (1) Regarding the shape of the protrusion In the above embodiment, the protrusion 25 is provided at the joint surface 21 at the end 22 on the winding core side. The position at which the protrusion 25 is arranged is not limited to this. Other aspects of the arrangement position of the protrusion 25 will be described using alternative aspects 1 to 3 as examples. Fig. 7 is an enlarged bottom view showing alternative aspect 1 of the arrangement position of the protrusion. Fig. 8 is an enlarged bottom view showing alternative aspect 2 of the arrangement position of the protrusion. Fig. 9 is an enlarged bottom view showing alternative aspect 3 of the arrangement position of the protrusion. In the above embodiment, the protrusion 25 is formed so that only a portion of the winding core portion side end 22 protrudes. The shape of the protrusion 25 is not limited to this. Another shape of the protrusion 25 will be described using another aspect 1 as an example. Fig. 10 is a cross-sectional view corresponding to the line VV in Fig. 2 showing another aspect 1 of the shape of the protrusion, where (a) is a cross-sectional view of the shape of the protrusion at the end on the first winding core portion side, and (b) is a cross-sectional view of the shape of the protrusion at the end opposite the first winding core portion.

[0045] (1-1) Another aspect of the arrangement position 1 In FIG. 7, the protrusion 25 is provided at the winding core opposite end 23, which is the end opposite to the winding core 11 side on the joint surface 21. Specifically, on the first joint surface 21a, the protrusion 25 is provided at the first winding core opposite end 23a. The first winding core opposite end 23a is along the end face of the first electrode 20a extending in the W direction on the side opposite to the winding core 11. The protrusion 25 is formed long along the first winding core opposite end 23a in the first joint surface 21a. Similarly, on the second joint surface 21b (see FIG. 1), the protrusion 25 can be formed long along the end face of the second electrode 20b extending in the W direction at the second winding core opposite end 23b (see FIG. 1). The protrusion 25 of the winding core opposite end 23 also serves as an anchor that efficiently fastens the end of the first wire 30 to the joint surface 21. This makes it possible to further improve the joint strength between the electrode 20 and the end of the first wire 30. The protrusion 25 can be provided in a shape that extends long on at least one of the first joint surface 21a and the second joint surface 21b, and on at least one of the winding core portion side end 22 and the winding core portion opposite end 23.

[0046] (1-2) Another aspect of the arrangement position 2 In Fig. 8, the protrusion 25 is provided in the center between the winding core portion side end 22 and the winding core portion opposite end 23 on the joint surface 21. Specifically, the protrusion 25 is formed long in the W direction in the center of the first joint surface 21a. Similarly, the protrusion 25 can be formed long in the W direction in the center of the second joint surface 21b (see Fig. 1). The protrusion 25 can be provided in a shape that extends long in at least one of the winding core portion side end 22, the winding core portion opposite end 23, and the center on at least one of the first joint surface 21a and the second joint surface 21b.

[0047] (1-3) Another aspect of the arrangement position 3 In FIG. 9, the protrusion 25 is not formed in a shape that extends long in the W direction, but in a shape that protrudes locally. In the example of FIG. 9, a plurality of protrusions 25 having a locally protruding shape are formed in a dispersed manner on the first joint surface 21a. Similarly, a plurality of protrusions 25 having a locally protruding shape can be formed in a dispersed manner on the second joint surface 21b. The protrusions 25 may be provided in at least one of a shape that extends long at the core part side end 22, a shape that extends long at the core part opposite end 23, a shape that extends long at the center, and a locally protruding shape, and a plurality of shapes may be combined. The protrusions 25 having a plurality of locally protruding shapes may be provided along the W direction at the core part side end 22, may be provided along the W direction at the core part opposite end 23, or may be provided along the W direction at the center. Furthermore, when joining the electrode 20 and the first wire 30, so long as the end of the first wire 30 straddles the protrusion 25 and is joined to the joining surface 21, the number of protrusions 25 having a locally protruding shape is not limited and may be, for example, one.

[0048] (1-4) Another aspect of the shape 1 10, the protrusion 25a of the first electrode 20a will be described, but the protrusion 25a of the second electrode 20b can be formed in the same manner. In FIG. 10(a), the protrusion 25a is formed by forming the first winding core side end 22a of the first electrode 20a into a shape that jumps up. The protrusion 25a is raised from the first bottom surface 12a1 by jumping up in a state in which the first winding core side end 22a is inclined with respect to the flat portion other than the first winding core side end 22a on the side away from the first bottom surface 12a1 in the T direction (direction perpendicular to the axial direction). In other words, the first winding core side end 22a of the first electrode 20a is raised from the first bottom surface 12a1 up to its closest position to the winding core 11.

[0049] 10(b), the first winding core opposite end 23a of the first electrode 20a is formed in a spring-up shape to form a protrusion 25b. The protrusion 25b rises up from the first bottom surface 12a1 by springing up the first winding core opposite end 23a in a tilted state with respect to the flat portion other than the first winding core opposite end 23a on the side away from the first bottom surface 12a1 in the T direction. In other words, the first winding core opposite end 23a of the first electrode 20a is in a state of being raised up from the first bottom surface 12a1 to the side closest to the winding core 11.

[0050] As shown in Figs. 10(a) and 10(b), the protrusions 25a and 25b are formed in a state in which the winding core side end 22 and the winding core opposite end 23 are raised from the bottom surface of the flange 12, so that the end of the first wire 30 can be more easily hooked onto the raised protrusions 25a and 25b. Therefore, the raised protrusions 25a and 25b can improve the joint strength between the electrode 20 and the end of the first wire 30. The protrusion 25a, in which the winding core side end 22 is raised, can improve the joint strength between the electrode 20 and the end of the first wire 30 more than the protrusion 25b. As described above, the tension of the end of the first wire 30 acts largely on the corner of the joint surface 21 near the winding core side end 22. Since the protrusion 25a corresponds to this corner, the end of the first wire 30 can be hooked onto the protrusion 25a in a portion where the tension of the first wire 30 is greater, which makes it easier to increase the joint strength.

[0051] As shown in FIG. 10, when at least one of the winding core side end 22 and the winding core opposite end 23 of the electrode 20 made of a metal plate is formed as the protrusions 25a and 25b, for example, when forming the electrode 20 made of a metal plate, a protrusion is provided at the end of a die so as to correspond to the protrusions 25a and 25b. By pressing a die having a protrusion formed at its end against the metal plate that becomes the electrode 20, the end of the electrode 20 is in a state of jumping up, and the protrusions 25a and 25b can be formed. When the protrusions 25a and 25b are formed at the end of the electrode 20 in this way, the force caused by the jumping up due to the pressing can be released to the outside of the die and the electrode 20, so that the protrusions 25a and 25b can be formed with a relatively small force without requiring a large force during molding. Therefore, the stress applied to the electrode 20 when the protrusions 25a and 25b are formed can be suppressed, and the strength reduction of the electrode 20 can be suppressed. In addition, forming the protrusions 25a and 25b at the end of the joint surface 21 makes it easier to mold, for example, by making the pressing force between the die and the electrode 20 relatively small.

[0052] On the other hand, the protrusions 25 in FIG. 1 of the embodiment and FIGS. 7 to 9 of the alternative embodiments 1 to 3 are formed so as to partially protrude within the plane of the flat portion of the electrode 20 made of a flat metal plate, unlike the protrusions 25a and 25b in the jumped-up state in FIG. 10. When such a protrusion 25 is formed, for example, when forming the electrode 20 made of a metal plate, a protrusion is partially provided at a desired position within the plane of the flat surface of the mold so as to correspond to the protrusion 25. By pressing the mold with the protrusion partially formed against the metal plate that becomes the electrode 20, the desired position of the electrode 20 is pressed and raised, thereby forming the protrusion 25. When the protrusion 25 is partially formed within the plane of the electrode 20 in this way, the electrode 20 is partially bent up and down significantly. Therefore, when the protrusion 25 is partially formed within the plane of the joint surface 21, it is necessary to press the mold more strongly than when the protrusions 25a and 25b in the jumped-up state are formed at the end of the joint surface 21.

[0053] (1-5) Other aspects (a) 7 and 8, the protrusion 25 is formed to extend long in the W direction. However, as long as the end of the first wire 30 is joined to the joining surface 21 of the electrode 20 in a state in which the first wire 30 straddles the protrusion 25, the protrusion 25 may be formed to be long in the L direction.

[0054] (b) In the above embodiment, the cross-sectional shape of the protrusion 25 is generally symmetrical in the L direction in cross-sectional view. However, the shape of the protrusion 25 is not limited to this. For example, the protrusion 25 may protrude while inclining toward the opposite side to the winding core 11 side in cross-sectional view. In other words, the direction in which the protrusion 25 protrudes from the joint surface 21 toward the tip and the direction of the tension generated in the first wire 30 may intersect. In this case, the end of the first wire 30 is likely to be caught by the protrusion 25 due to the tension of the first wire 30 from the winding core 11 side, and the end of the first wire 30 is unlikely to come off the protrusion 25. Therefore, the protrusion 25 becomes an anchor that efficiently holds the first wire 30 to the electrode 20, and the joint strength between the electrode 20 and the end of the first wire 30 can be improved.

[0055] (c) Furthermore, the cross-sectional shape of the protrusion 25 is not limited to the tapered shape as in the above embodiment. As long as the end of the first wire 30 is joined to the joining surface 21 in a state of straddling the protrusion 25, the cross-sectional shape of the protrusion 25 may be rectangular, square, or the like.

[0056] (d) In the above embodiment, the protrusion 25 is provided corresponding to the joint surface 21. That is, for example, in FIG. 1 , the protrusion 25 is provided at the end 22 on the winding core portion side of the joint surface 21. However, the protrusion 25 may be provided corresponding to the position of the end of the first wire 30 on the joint surface 21. For example, the protrusion 25 may be provided corresponding to the tip of the end of the first wire 30 on the joint surface 21, or the protrusion 25 may be provided corresponding to the base of the end of the first wire 30 on the joint surface 21.

[0057] (2) Electrode placement (2-1) Electrode placement on the side of the flange In the above embodiment, the first and second electrodes 20a, 20b are disposed on the first bottom surface 12a1 of the first flange portion 12a and the second bottom surface 12b1 of the second flange portion 12b. However, as long as the first and second ends 30a, 30b of the first wire 30 and the first and second electrodes 20a, 20b are joined, the positions of the first and second electrodes 20a, 20b are not limited thereto. For example, the first and second electrodes 20a, 20b may be disposed on the first side surface 12a3 of the first flange portion 12a and the second side surface 12b3 of the second flange portion 12b. This example will be described below by taking a coil component 100A according to a modified example as an example. FIG. 11 is an external perspective view showing an example of a coil component according to a modified example of the present invention.

[0058] The coil component 100A according to the modification is different from the coil component 100 according to the embodiment described above in that the first and second electrodes 20a, 20b are disposed on the first side surface 12a3 and the second side surface 12b3. The first end portion 30a of the first wire 30 extends toward the first electrode 20a on the first side surface 12a3 side and is joined to the first electrode 20a by the first joint portion 27a in a state of straddling the protrusion 25. The second end portion 30b of the first wire 30 extends toward the second electrode 20b on the second side surface 12b3 side and is joined to the second electrode 20b by the second joint portion 27b in a state of straddling the protrusion 25. The following mainly describes the differences from the coil component 100 according to the embodiment described above.

[0059] 11, the first electrode 20a is disposed at one end of the first bottom surface 12a1 in the W direction in the first flange 12a, and is bent from the first bottom surface 12a1 to be continuously disposed along the first side surface 12a3. The second electrode 20b is disposed at one end of the second bottom surface 12b1 in the W direction in the second flange 12b, and is bent from the second bottom surface 12b1 to be continuously disposed along the second side surface 12b3.

[0060] The first electrode 20a on the first side surface 12a3 has a first bonding surface 21a where the first electrode 20a and the first end 30a are bonded. The second electrode 20b on the second side surface 12b3 has a second bonding surface 21b where the second electrode 20b and the second end 30b are bonded. The first and second bonding surfaces 21a, 21b face the sides of the first and second electrodes 20a, 20b when the first and second bottom surfaces 12a1, 12b1 of the first and second flanges 12a, 12b face upward in FIG. 11. In this case, the first and second bottom surfaces 12a1, 12b1 become mounting surfaces.

[0061] The first and second bonding surfaces 21a, 21b are each provided with a protrusion 25 along the first and second winding core portion side ends 22a, 22b along the end faces of the first and second electrodes 20a, 20b extending in the T direction. With the first wire 30 straddling the protrusion 25 of the first bonding surface 21a, the first electrode 20a and the first end 30a are bonded by a first bonding portion 27a made of an alloy layer. With the first wire 30 straddling the protrusion 25 of the second bonding surface 21b, the second electrode 20b and the second end 30b are bonded by a second bonding portion 27b made of an alloy layer.

[0062] 11, the turn of the first wire 30 closest to the first flange 12a has a first separated portion 31a separated from the winding core portion 11 and a first end portion 30a on the same side with respect to the winding core portion 11. Also, the turn of the first wire 30 closest to the second flange 12b has a second separated portion 31b separated from the winding core portion 11 and a second end portion 30b on the same side with respect to the winding core portion 11.

[0063] 11, the first and second electrodes 20a, 20b are arranged on the first and second side surfaces 12a3, 12b3 in addition to the first and second bottom surfaces 12a1, 12b1. However, the first and second electrodes 20a, 20b may be arranged only on the first and second side surfaces 12a3, 12b3.

[0064] (2-2) Arrangement of the first and second electrodes on the same side In the above embodiment, the first and second electrodes 20a, 20b are arranged on the same side with respect to the winding core portion 11. However, depending on the performance of the coil device 100, the first and second electrodes 20a, 20b may be arranged diagonally across the winding core portion 11. For example, the first electrode 20a can be arranged at one end of the first bottom surface 12a1 in the W direction in the first flange portion 12a. Meanwhile, the second electrode 20b can be arranged at the other end of the second bottom surface 12b1 in the W direction in the second flange portion 12b.

[0065] (3) Number of wires In the above embodiment, the wire 30 includes only one first wire 30. However, the number of wires is not limited to this, and two or more wires may be included. The electrodes include a plurality of pairs of electrodes to which both ends (one end and the other end) of each wire are respectively joined. At least one protrusion is provided on at least one of the joint surfaces of each electrode with the end of the wire.

[0066] As an example, the wire may include two wires, a first wire 30 and a second wire 32. A coil component 100B including the first wire 30 and the second wire 32 will be described below. Fig. 12 is a bottom view showing an example of a coil component according to another modified example of the present invention. The following mainly describes the differences from the coil component 100 according to the embodiment.

[0067] The coil device 100B includes a core 10, an electrode 20, a first wire 30, and a second wire 32. The core 10 has a winding core portion 11 and two pairs of flange portions 12. The first and second wires 30, 32 are wound around the winding core portion 11 by bifilar winding. The first wire 30 includes a first end portion 30a which is one end portion, and a second end portion 30b which is the other end portion. The second wire 32 includes a third end portion 30c which is one end portion, and a fourth end portion 30d which is the other end portion.

[0068] The electrode 20 includes a first electrode 20a, a second electrode 20b, a third electrode 20c, and a fourth electrode 20d. The first electrode 20a and the third electrode 20c face each other in the first flange 12a across the axial direction that is the center of the winding core 11. The first electrode 20a is provided at one end of the first flange 12a, and the third electrode 20c is provided at the other end of the first flange 12a. The second electrode 20b and the fourth electrode 20d face each other in the second flange 12b across the axial direction that is the center of the winding core 11. The second electrode 20b is provided at one end of the second flange 12b, and the fourth electrode 20d is provided at the other end of the second flange 12b.

[0069] A first end 30a of the first wire 30 is joined to the first electrode 20a. A second end 30b of the first wire 30 is joined to the second electrode 20b. A third end 30c of the second wire 32 is joined to the third electrode 20c. A fourth end 30d of the second wire 32 is joined to the fourth electrode 20d.

[0070] The first electrode 20a on the first bottom surface 12a1 has a first bonding surface 21a where the first electrode 20a and the first end 30a are bonded. The second electrode 20b on the second bottom surface 12b1 has a second bonding surface 21b where the second electrode 20b and the second end 30b are bonded. The third electrode 20c on the first bottom surface 12a1 has a third bonding surface 21c where the third electrode 20c and the third end 30c are bonded. The fourth electrode 20d on the second bottom surface 12b1 has a fourth bonding surface 21d where the fourth electrode 20d and the fourth end 30d are bonded.

[0071] At least one protrusion 25 is provided on at least one of the first to fourth bonding surfaces 21a to 21d. In the example of FIG. 12, the first bonding surface 21a has a protrusion 25 protruding from the first bonding surface 21a at the first winding core portion side end 22a. The second bonding surface 21b has a protrusion 25 protruding from the second bonding surface 21b at the second winding core portion side end 22b. The third bonding surface 21c has a protrusion 25 protruding from the third bonding surface 21c at the third winding core portion side end 22c. The fourth bonding surface 21d has a protrusion 25 protruding from the fourth bonding surface 21d at the fourth winding core portion side end 22d. In the example of FIG. 12, the first to fourth winding core portion side ends 22a to 22d are aligned along the end faces extending in the W direction of the electrode 20, as in the above embodiment. Although not described here, the protrusion 25 may be provided on at least one of the first to fourth winding core opposite ends 23a to 23d.

[0072] With the first wire 30 straddling the protrusion 25 provided on the first bonding surface 21a, the first electrode 20a and the first end 30a of the first wire 30 are bonded by a first bonding portion 27a made of an alloy layer. At this time, the first end 30a of the first wire 30 contacts the protrusion 25 directly or through the first bonding portion 27a. Also, with the first wire 30 straddling the protrusion 25 provided on the second bonding surface 21b, the second electrode 20b and the second end 30b of the first wire 30 are bonded by a second bonding portion 27b made of an alloy layer. At this time, the second end 30b of the first wire 30 contacts the protrusion 25 directly or through the second bonding portion 27b. With the second wire 32 straddling the protrusion 25 provided on the third joint surface 21c, the third electrode 20c and the third end 30c of the second wire 32 are joined by a third joint 27c made of an alloy layer. At this time, the third end 30c of the second wire 32 contacts the protrusion 25 directly or through the third joint 27c. Also, with the second wire 32 straddling the protrusion 25 provided on the fourth joint surface 21d, the fourth electrode 20d and the fourth end 30d of the second wire 32 are joined by a fourth joint 27d made of an alloy layer. At this time, the fourth end 30d of the second wire 32 contacts the protrusion 25 directly or through the fourth joint 27d.

[0073] With the above configuration, even if there are a plurality of wires, the bonding strength between the electrode 20 and the end of the wire can be improved by the projections 25, as in this embodiment.

[0074] (4) Regarding electrodes coated with conductive metal In the above embodiment, the electrode 20 is a metal terminal electrode formed from a metal plate. However, the electrode 20 is not limited to this, and the electrode 20 can be formed as a coated electrode by applying a conductive paste containing a conductive metal to the flange portion 12 of the core 10 and firing the paste. FIG. 13 is a cross-sectional view of a coil component having an electrode using a coated electrode taken along line VV in FIG. 2. In FIG. 13, the winding core portion 11 is removed, and the first flange portion 12a, the protrusion 25, the first end portion 30a, etc. are simplified to be shown. Since the first and second electrodes 20a and 20b have the same configuration, the first electrode 20a will be described below.

[0075] The first electrode 20a, which is a coated electrode shown in FIG. 13, is formed to have a protrusion 25. Such a first electrode 20a can be formed by providing a core protrusion 26 protruding from the first bottom surface 12a1 on the first flange portion 12a of the core 10. A die having, for example, a recess corresponding to the core protrusion 26 is prepared, the material of the core 10 is poured into the die, and the material of the core 10 is pressed by the die and fired to form the core 10 on which the core protrusion 26 is formed on the first bottom surface 12a1 of the first flange portion 12a. In the example of FIG. 13, the core protrusion 26 is formed on the winding core portion 11 side of the first bottom surface 12a1. When a conductive paste is applied to the first bottom surface 12a1 on which the core protrusion 26 is formed, the conductive paste is applied in a raised manner along the protrusion of the core protrusion 26. By firing this conductive paste, the first electrode 20a, which is a coated electrode having a protrusion 25, is formed.

[0076] With the first wire 30 straddling the protrusion 25 provided on the first joint surface 21a, the first electrode 20a, which is a coated electrode, and the first end 30a of the first wire 30 are joined by the first joint 27a consisting of an alloy layer.

[0077] (5) Aerial wiring In the above embodiment, the first end 30a and the first separated portion 31a of the turn of the first wire 30 located closest to the first flange 12a face each other across the winding core 11. The aerial wiring portion from the first separated portion 31a to the first electrode 20a is relatively long. However, depending on the type of coil component, the first separated portion 31a and the first end 30a may be on the same side of the winding core 11, and the aerial wiring portion may be short.

[0078] When the separation portion 31 where the first wire 30 is separated from the winding core portion 11 and the end of the first wire 30 are on the same side of the winding core portion 11, the aerial wiring portion is short as described above, and therefore the tension from the end of the first wire 30 toward the winding core portion 11 is small. Even in this case, if the joint surface 21 is provided with the protrusion 25, the joint strength between the electrode 20 and the end of the first wire 30 can be further improved.

[0079] (6) Bonding of electrodes and wires In the above embodiment, the electrode 20 and the end of the first wire 30 are joined by a joint 27 made of an alloy layer, with the first wire 30 straddling the protrusion 25 provided on the joint surface 21. In this case, the alloy layer is formed by using laser welding, thermocompression bonding, or the like. It is sufficient that the electrode 20 and the end of the first wire 30 are joined, and laser welding, thermocompression bonding, or the like do not have to be used. In addition, it is not necessarily necessary to form an alloy layer at the joint 27 between the electrode 20 and the end of the first wire 30.

[0080] For example, the end of the first wire 30 may be bonded to the electrode 20 with a conductive adhesive while the first wire 30 straddles the protrusion 25 provided on the joint surface 21 of the electrode 20, thereby joining the electrode 20 and the end of the first wire 30. Furthermore, for example, the end of the first wire 30 may be bonded to the electrode 20 with a conductive material such as solder while the first wire 30 straddles the protrusion 25 provided on the joint surface 21 of the electrode 20.

[0081] <1> a core having a winding core portion extending in an axial direction and a first flange portion and a second flange portion provided at both ends of the winding core portion in the axial direction, an electrode including a first electrode and a second electrode provided on the first flange portion and the second flange portion, respectively; a first wire wound around the winding core and having a first end joined to the first electrode and a second end joined to the second electrode, the first electrode has a first bonding surface to which the first end is bonded; The first joint surface is provided with at least one protrusion, A coil component, wherein the first end of the first wire is joined to the first joint surface in a state where the first wire straddles at least one of the protrusions provided on the first joint surface.

[0082] <2> The protrusion is The first joint surface is provided on at least one of a first winding core side end portion, which is an end portion on the winding core side, and a first winding core opposite end portion, which is an end portion opposite to the winding core side facing the first winding core side end portion. <1> The coil component according to claim 1.

[0083] <3> The protrusion is provided on the first winding core side end portion. <2> The coil component according to claim 1.

[0084] <4> The protrusion is embedded in the first end of the first wire. <1> ~ <3> 2. The coil component according to claim 1 .

[0085] <5> The first electrode and the second electrode are metal terminal electrodes made of metal plates arranged at least on the first flange portion and the second flange portion, or The first electrode and the second electrode are coated electrodes in which a conductive metal is coated on at least the first flange portion and the second flange portion. <1> ~ <4> 2. The coil component according to claim 1 .

[0086] <6> a first end portion of the first wire that is closest to the first flange portion and is separated from the winding core portion, the first end portion of the first wire facing each other across the winding core portion, and the protrusion is provided on the first joint surface of the first electrode. <1> ~ <5> 2. The coil component according to claim 1 .

[0087] <7> a second wire having a third end and a fourth end; the electrodes further include a third electrode provided on the first flange and opposed to the first electrode across the axial direction, and a fourth electrode provided on the second flange and opposed to the second electrode across the axial direction, the third end is one end of the second wire joined to the third electrode, the fourth end is the other end of the second wire joined to the fourth electrode, the third electrode and the fourth electrode each have a third bonding surface to which the third end portion is bonded and a fourth bonding surface to which the fourth end portion is bonded, The third bonding surface is provided with at least one protrusion, The third end of the second wire is joined to the third joint surface in a state where the second wire straddles at least one of the protrusions provided on the third joint surface. <1> ~ <6> 2. The coil component according to claim 1 .

[0088] <8> a second wire having a third end and a fourth end; the electrodes further include a third electrode provided on the first flange and opposed to the first electrode across the axial direction, and a fourth electrode provided on the second flange and opposed to the second electrode across the axial direction, the third end is one end of the second wire joined to the third electrode, the fourth end is the other end of the second wire joined to the fourth electrode, the third electrode and the fourth electrode each have a third bonding surface to which the third end portion is bonded and a fourth bonding surface to which the fourth end portion is bonded, The fourth bonding surface is provided with at least one protrusion, The fourth end of the second wire is joined to the fourth joint surface in a state where the second wire straddles at least one of the protrusions provided on the fourth joint surface. <1> ~ <7> 2. The coil component according to claim 1 .

[0089] <9> the first electrode and the first end are joined via an alloy layer; <1> ~ <8> 2. The coil component according to claim 1 .

[0090] <10> The alloy layer contains Cu and at least one of Sn and Ni. <9> The coil component according to claim 1.

[0091] <11> The height of the protrusion provided on the first bonding surface is in the range of 1 / 10 to 1 / 4 of the wire diameter of the first wire. <1> ~ <10> 2. The coil component according to claim 1 .

[0092] <12> The protrusion provided on the first winding core side end portion, which is the end portion of the first joint surface on the winding core side, is formed in a shape such that the first winding core side end portion of the first electrode jumps up in a direction away from the first flange portion. <1> ~ <11> 2. The coil component according to claim 1 . [Explanation of symbols]

[0093] 10: Core 11: Winding core 12: Flange 12a, 12b: First and second flanges 12a1, 12b1: 1st and 2nd bottom 12a2, 12b2: 1st and 2nd top surface 12a3, 12b3: 1st, 2nd side 20: Electrode 20a~20d: 1st~4th electrode 21: Joint surface 21a~21d: 1st~4th joint surface 22: Winding core side end 22a~22d: 1st~4th volume core side end 23: Opposite end of core 23a to 23d: 1st to 4th winding core opposite ends 25: Protrusion 25a, 25b: Protrusion 26: Core protrusion 27: Joint 27a~27d: 1st~4th joint 30: First wire (wire) 32: Second wire 30a~30d: 1st~4th end (end) 31: Separation part 31a, 31b: 1st and 2nd separation part 100: Coil parts 100A: Coil parts 100B: Coil parts

Claims

1. a core having a winding core portion extending in an axial direction and a first flange portion and a second flange portion provided at both ends of the winding core portion in the axial direction, an electrode including a first electrode and a second electrode provided on the first flange portion and the second flange portion, respectively; a first wire wound around the winding core and having a first end joined to the first electrode and a second end joined to the second electrode, the first electrode has a first bonding surface to which the first end is bonded; The first joint surface is provided with at least one protrusion, The first end of the first wire is joined to the first joint surface in a state where the first wire straddles at least one of the protrusions provided on the first joint surface. Coil parts.

2. The protrusion is 2. The coil component according to claim 1, wherein the first joint surface is provided on at least one of a first winding core side end, which is an end portion on the winding core side, and a first winding core opposite end, which is an end portion opposite the winding core side facing the first winding core side end.

3. The coil component according to claim 2 , wherein the protrusion is provided on an end portion of the first winding core portion.

4. The coil component according to claim 1 , wherein the projection is embedded in the first end of the first wire.

5. The first electrode and the second electrode are metal terminal electrodes made of metal plates arranged at least on the first flange portion and the second flange portion, or The coil component according to claim 1 , wherein the first electrode and the second electrode are coated electrodes in which a conductive metal is coated on at least the first flange portion and the second flange portion.

6. 3. The coil component according to claim 1, wherein a first end portion of the first wire is disposed opposite a first separated portion of the first wire that is separated from the winding core portion, and the first end portion is disposed across the winding core portion, and the protrusion is provided on the first joint surface of the first electrode.

7. a second wire having a third end and a fourth end; the electrodes further include a third electrode provided on the first flange and opposed to the first electrode across the axial direction, and a fourth electrode provided on the second flange and opposed to the second electrode across the axial direction, the third end is one end of the second wire joined to the third electrode, the fourth end is the other end of the second wire joined to the fourth electrode, the third electrode and the fourth electrode each have a third bonding surface to which the third end portion is bonded and a fourth bonding surface to which the fourth end portion is bonded, The third bonding surface is provided with at least one protrusion, the third end of the second wire is joined to the third joint surface in a state in which the second wire straddles at least one of the projections provided on the third joint surface; The coil component according to claim 1 or 2.

8. a second wire having a third end and a fourth end; the electrodes further include a third electrode provided on the first flange and opposed to the first electrode across the axial direction, and a fourth electrode provided on the second flange and opposed to the second electrode across the axial direction, the third end is one end of the second wire joined to the third electrode, the fourth end is the other end of the second wire joined to the fourth electrode, the third electrode and the fourth electrode each have a third bonding surface to which the third end portion is bonded and a fourth bonding surface to which the fourth end portion is bonded, The fourth joint surface is provided with at least one protrusion, the fourth end of the second wire is joined to the fourth joint surface in a state in which the second wire straddles at least one of the protrusions provided on the fourth joint surface; The coil component according to claim 1 or 2.

9. The coil component according to claim 1 , wherein the first electrode and the first end are joined via an alloy layer.

10. The coil component according to claim 9 , wherein the alloy layer contains Cu and at least one of Sn and Ni.

11. The coil component according to claim 1 , wherein a height of the protrusion provided on the first joint surface is in a range of 1 / 10 to 1 / 4 of a wire diameter of the first wire.

12. 3. The coil component according to claim 1, wherein the protrusion provided at the first winding core portion side end portion, which is the end portion of the first joint surface on the winding core portion side, is formed in a shape such that the first winding core portion side end portion of the first electrode jumps up in a direction away from the first flange portion.

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