JP6729223B2 - Coil component and manufacturing method thereof - Google Patents

Description

The present invention relates to a coil component, and more particularly to a coil component using a rectangular wire.

Coil parts formed by winding a wire around a winding core are widely used for applications such as removing noise superimposed on signals and power supplies. In particular, a coil component for a power source uses a wire having a large diameter because a current flowing through the wire is larger than that of a coil component for a signal. When a wire with a large diameter is used, the size of the coil component in the axial direction increases, so a so-called flat wire having a substantially rectangular cross section may be used to reduce the size (see Patent Document 1).

Since the coil component using the flat wire has a large capacitance component between adjacent turns, in Patent Document 1, a space component is provided between the adjacent turns to reduce the capacitance component between the windings.

JP-A-8-236364

However, in the coil component described in Patent Document 1, since both ends of the coil are fixed to one end side in the axial direction of the winding core portion, the spring property of the coil changes the distance between adjacent turns. There was a fear. As a result, there is a problem that the capacitance component between adjacent turns becomes unstable.

Therefore, an object of the present invention is to stabilize the capacitance component between adjacent turns in a coil component using a rectangular wire.

A coil component according to the present invention comprises a core having a first winding core portion and a flat wire wound around the first winding core portion a plurality of times and having a radial thickness larger than a radial thickness. A first coil, a first terminal electrode provided on the core, located on one end side in the axial direction of the first winding core portion, and having one end of the first coil fixed, and the core And a second terminal electrode that is provided on the other end side in the axial direction of the first winding core portion and has the other end of the first coil fixed thereto. A space is provided between at least one adjacent turn.

According to the present invention, since both ends of the first coil made of the rectangular wire are fixed to the terminal electrodes provided on both sides in the axial direction, the posture of the coil component is stable. Therefore, it is possible to obtain the characteristics as designed regardless of the usage state. Further, the presence of the space makes it possible to reduce the capacitive component between adjacent turns.

In the present invention, it is preferable that the space has a constant distance in the axial direction, and it is particularly preferable that a space having a constant distance in the axial direction is provided between adjacent turns of the first coil. According to this, the capacitance component between the adjacent turns can be further reduced, and the capacitance component between the adjacent turns does not change due to the posture of the coil and the like.

In the present invention, the core preferably has a ring structure. According to this, since the closed magnetic circuit is formed by the core, the inductance can be improved. In this case, it is more preferable that the core has an integral structure having no joint. According to this, since the magnetic resistance does not increase due to the existence of the joint portion, the inductance can be further improved.

In the present invention, the distance of the space in the axial direction is preferably smaller than the thickness of the first coil in the axial direction. Even with such a configuration, since the space between adjacent turns is kept constant, it is possible to obtain stable characteristics while reducing the size in the axial direction.

A coil component according to the present invention includes a second coil, which is wound around a second winding core portion of the core a plurality of times, and includes a flat wire having a radial thickness larger than a thickness in the axial direction, and the core. And a third terminal electrode that is located on one end side of the second winding core portion in the axial direction and to which one end of the second coil is fixed, and the second terminal electrode is provided on the core. A fourth terminal electrode, which is located on the other end side in the axial direction of the winding core portion and to which the other end of the second coil is fixed, is further provided, and between each adjacent turn of the second coil, It is preferable that a space having a constant distance in the axial direction is provided. According to this, it becomes possible to wind two coils around one core.

In this case, it is preferable that the first coil and the second coil have the same number of turns, and the space of the first coil and the space of the second coil have the same width. According to this, the coil component can be used as a common mode filter.

According to the present invention, it is possible to stabilize the capacitance component between adjacent turns of a coil component that uses a rectangular wire. This makes it possible to obtain the characteristics as designed.

FIG. 1 is a schematic perspective view showing the outer appearance of a coil component 10 according to a preferred embodiment of the present invention. FIG. 2 is a schematic perspective view showing the structure of the core 20. FIG. 3 is a schematic top view showing the structure of the coils 31, 32. FIG. 4 is a schematic perspective view showing the structure of the terminal electrode 41. FIG. 5 is a schematic diagram for explaining a winding method of the coil 31. FIG. 6 is a schematic diagram for explaining a winding method of the coil 31.

Hereinafter, preferred embodiments of the present invention will be described in detail with reference to the accompanying drawings.

FIG. 1 is a schematic perspective view showing the outer appearance of a coil component 10 according to a preferred embodiment of the present invention.

As shown in FIG. 1, the coil component 10 according to the present embodiment includes a core 20 having an annular structure, first and second coils 31 and 32 using a rectangular wire, and four terminals attached to the core 20. It is composed of electrodes 41 to 44. The structure of the core 20 is shown in FIG. 2, the structure of the coils 31 and 32 is shown in FIG. 3, and the structure of the terminal electrode 41 is shown in FIG. The structure of the other terminal electrodes 42 to 44 is similar to the structure shown in FIG.

The core 20 is made of a magnetic material such as ferrite and has first and second winding core portions 21 and 22 and first and second connecting portions 23 and 24, as shown in FIG. Each of the winding core parts 21 and 22 has an x direction as an axial direction, and its yz cross section is substantially circular. The first connecting portion 23 is located on one end side of the winding core portions 21 and 22 in the x direction and has recesses 51 and 53 to which the terminal electrodes 41 and 43 are attached. Similarly, the second connecting portion 24 is located on the other end side of the winding core portions 21 and 22 in the x direction and has recesses 52 and 54 to which the terminal electrodes 42 and 44 are attached.

The core 20 has an annular structure including winding core portions 21 and 22 and connecting portions 23 and 24, and has an integral structure having no joint portion. In the present invention, it is not essential that the core 20 has an annular structure, but since a closed magnetic circuit is formed by using the core 20 having an annular structure, the inductance can be improved. Further, in the present invention, it is not essential that the core 20 has an integral structure having no joint portion, but if the core 20 having the integral structure is used, a plurality of core members are bonded by using an adhesive or the like. Since the magnetic gap does not exist unlike the case of using the magnetized material, the inductance can be further improved.

As described above, the first to fourth terminal electrodes 41 to 44 are attached to the recesses 51 to 54 provided in the core 20, respectively. In the present embodiment, the concave portions 60 are provided on the xy planes of the connection portions 23 and 24, and the convex portions 66 of the terminal electrodes 41 to 44 are fitted into the concave portions, so that the terminal electrodes 41 to 44 become the core 20. Fixed to. In addition to this, the terminal electrodes 41 to 44 may be fixed to the core 20 using an adhesive.

As shown in FIG. 4, the terminal electrode 41 includes a vertical portion 61 that covers a side surface (yz plane) of the connection portion 23, a horizontal portion 62 that covers an upper surface (xy plane) of the connection portion 23, and a bottom surface of the connection portion 23 ( It has a horizontal portion 63 that covers the (xy plane). The vertical portion 61 fits into the corresponding recess 51. Further, the horizontal portions 62 and 63 are provided with convex portions 66, and these convex portions 66 fit into the concave portions 60 provided in the connecting portion 23.

Further, the terminal electrode 41 is provided with a fixing piece 64 for pressing the coil 31 and a welding piece 65 used for welding. When the coil component 10 is manufactured, the one end 31a of the coil 31 is pressed and fixed by the fixing piece 64, and the welding piece 65 is bent to perform welding. It is fixed to 41. When welding is performed, the welding ball 70 shown in FIG. 1 is formed, and both are firmly connected electrically and mechanically. Since the same applies to the other terminal electrodes 42 to 44, duplicate description will be omitted.

As shown in FIG. 3, each of the coils 31 and 32 is composed of a rectangular wire. The flat wire is a coated conductive wire whose core material is copper or the like, and has a substantially rectangular cross section. In the state of the coils 31 and 32, the coils are wound so that the thickness in the radial direction is larger than the thickness in the axial direction. By using such a rectangular wire, the lengths of the coils 31 and 32 in the axial direction (x direction) can be shortened while ensuring a sufficient cross-sectional area. This makes it possible to reduce the size of the coil component 10 in the x direction while reducing the DC resistance.

The one end 31a and the other end 31b of the coil 31 are connected to the first and second terminal electrodes 41 and 42, respectively, and the one end 32a and the other end 32b of the coil 32 are respectively the third and fourth terminal electrodes 43. , 44. In the present embodiment, since the coil 31 and the coil 32 have the same number of turns (7 turns in each case), the pair of terminal electrodes 41 and 43 is the input side and the pair of terminal electrodes 42 and 44 is the output side. It can be used as a common mode filter.

As shown in FIG. 3, spaces S are provided between adjacent turns of the coils 31 and 32, respectively. The space S is kept constant between the adjacent turns. That is, each space S of the coil 31 has a constant width, each space S of the coil 32 has a constant width, and the space S of the coil 31 and the space S of the coil 32 have the same width.

As a result, the capacitance component generated between adjacent turns is reduced, and the distribution is substantially constant, so that the characteristics as designed can be obtained. Moreover, since both ends of each coil 31, 32 are fixed to the corresponding terminal electrodes 41-44, the coils 31, 32 are hardly deformed by the spring property, and the space S is always kept constant. .. As a result, the capacitance component between adjacent turns does not change depending on the posture of the coil component 10 and the like, so that it is possible to obtain the designed characteristics regardless of the usage state. However, in the present invention, it is not essential that the space S having a constant width is provided between each adjacent turns, and it is sufficient if the space S having a predetermined width is provided between at least one adjacent turns.

The size of the space S is not particularly limited, but is preferably smaller than the thickness T of the coils 31, 32 in the axial direction. According to this, it becomes possible to obtain stable characteristics while reducing the size of the coil component 10 in the axial direction (x direction).

As described above, since the coil component 10 according to the present embodiment has the configuration in which the coils 31 and 32 having stable characteristics are connected in parallel, it can be suitably used as a common mode filter for a power supply. ..

Next, the method for manufacturing the coil component 10 according to the present embodiment will be described.

First, the core 20 having the shape shown in FIG. 2 is integrally molded using a mold or the like, and then the first jig 81 shown in FIG. The rectangular wire W is pushed out toward the tool 81. The first jig 81 has a surface 81 a that follows the outer peripheral shape of the coil 31, and if the rectangular wire W is fed so as to be pressed against this surface 81 a, the rectangular wire W circulates around the winding core 21. Is curved and molded.

Next, the second jig 82 shown in FIG. 6 is inserted between the bent flat wire W and the flat wire W before being bent before the flat wire W makes a complete turn. The second jig 82 is a plate-like body having a yz plane, and its thickness in the x direction is equal to the space S described above. By feeding out the flat wire W while sandwiching such a second jig 82, it becomes possible to wind the flat wire W around the winding core portion 21 while keeping the space S between adjacent turns constant.

When the winding of a predetermined number of turns is completed, the rectangular wire W is cut and both ends are bent. As a result, the first coil 31 is completed. The second coil 32 can also be formed using the same method. The winding work of the coils 31 and 32 may be performed separately or simultaneously.

After that, the four terminal electrodes 41 to 44 are attached to the core 20, and one end and the other end of the corresponding coils 31 and 32 are welded to complete the coil component 10 according to the present embodiment.

If the coil component 10 is created using such a method, the space S between adjacent turns matches the thickness of the second jig 82 in the x direction, so the space S between adjacent turns should be constant. Is possible. Further, the size of the space S can be changed by changing the thickness of the second jig 82 in the x direction. Moreover, since the rectangular wire W is wound around the winding core parts 21 and 22 while being curvedly formed, the coils 31 and 32 can be easily wound around the core 20 having an annular structure having no joint part. Is possible.

Although the preferred embodiments of the present invention have been described above, the present invention is not limited to the above embodiments, and various modifications can be made without departing from the gist of the present invention. It goes without saying that it is included in the range.

10 coil parts 20 core 21,22 core part 23,24 connection part 31,32 coil 31a, 32a coil one end 31b, 32b coil other end 41-44 terminal electrode 51-54 recessed part 61 vertical part 62, 63 horizontal part 64 fixing piece 65 welding piece 66 convex portion 70 welding balls 81, 82 jig 81a surface S space W flat wire

Claims (8)

A core having an integral structure having an annular structure and not having a joint portion, the first winding core portion and a first connecting portion located on one end side in the axial direction of the first winding core portion. A core having a second connecting portion located on the other end side of the first winding core portion in the axial direction ,
Said wound multiple times around the first core portion, a first coil formed of flat wire towards the thickness at a large diameter direction of the thickness in the axial direction,
A first terminal electrode provided on the core, located on one end side of the first winding core portion in the axial direction, and having one end of the first coil fixed thereto;
A second terminal electrode provided on the core, located on the other end side of the first winding core portion in the axial direction, and having the other end of the first coil fixed thereto;
The first and second connecting portions respectively have first and second upper surfaces parallel to the axial direction,
The first terminal electrode has a first horizontal portion covering the first upper surface,
The second terminal electrode has a second horizontal portion covering the second upper surface,
The one end of the first coil is bent and connected to the first horizontal portion such that a long side in a cross section is parallel to the axial direction,
The other end of the first coil is bent so that a long side in a cross section is parallel to the axial direction and connected to the second horizontal portion,
A coil component, wherein a space is provided between at least one adjacent turn of the first coil. The coil component according to claim 1, wherein the space has a constant distance in the axial direction. The coil component according to claim 2, wherein the space is provided between adjacent turns of the first coil. The coil component according to any one of claims 1 to 3 , wherein a distance of the space in the axial direction is smaller than a thickness of the first coil in the axial direction. A second coil formed of a rectangular wire which is wound around the second winding core portion of the core a plurality of times and has a thickness in the radial direction larger than that in the axial direction;
A third terminal electrode provided on the core, located on one end side in the axial direction of the second winding core portion, and having one end of the second coil fixed thereto;
A fourth terminal electrode provided on the core, located on the other end side of the second winding core portion in the axial direction, and having the other end of the second coil fixed thereto;
The third terminal electrode has a third horizontal portion covering the first upper surface,
The fourth terminal electrode has a fourth horizontal portion that covers the second upper surface,
The one end of the second coil is bent and connected to the third horizontal portion such that a long side in a cross section is parallel to the axial direction,
The other end of the second coil is bent so that a long side in a cross section is parallel to the axial direction and connected to the fourth horizontal portion,
The coil component according to claim 3, wherein a space having a constant distance in the axial direction is provided between adjacent turns of the second coil. Said first coil and said second coil are equal to each other the number of turns, it in claim 5, wherein said space of said first of said space and said second coil of the coil is the same width as each other Described coil parts. A first step of preparing an annular core having a winding core portion extending in the axial direction;
A second step of winding a coil made of a rectangular wire whose thickness in the radial direction is larger than that in the axial direction a plurality of times around the winding core portion,
The second step is
A first jig having a surface along the outer peripheral shape of the coil is set in the vicinity of the winding core portion, and the flat wire is fed so as to be pressed against the surface. A step of curving so as to go around,
Before the flat wire completely goes around, between the bent flat wire and the flat wire before being bent, a flat surface perpendicular to the axial direction is provided, and the flat wire has a predetermined thickness in the axial direction. By inserting a second jig having the above-mentioned second jig and unwinding the flat wire while sandwiching the second jig, thereby winding the flat wire around the winding core while keeping the space between adjacent turns constant. And the step of forming the coil by means of a step of forming the coil. Further comprising a third step of attaching first and second terminal electrodes to the core and connecting one end and the other end of the coil to the first and second terminal electrodes, respectively.
The second step further includes the step of winding the flat wire for a predetermined number of turns, cutting the flat wire, and bending both ends.
The core further has a first connecting portion located on one end side in the axial direction of the winding core portion and a second connecting portion located on the other end side in the axial direction of the winding core portion. ,
The first and second connecting portions respectively have first and second upper surfaces parallel to the axial direction,
The first terminal electrode has a first horizontal portion covering the first upper surface,
The second terminal electrode has a second horizontal portion covering the second upper surface,
The one end of the coil is bent so that a long side in a cross section is parallel to the axial direction and connected to the first horizontal portion,
The method for manufacturing a coil component according to claim 7, wherein the other end of the coil is bent so that a long side in a cross section is parallel to the axial direction and is connected to the second horizontal portion. ..

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