JP7218831B2 - coil parts - Google Patents

Description

TECHNICAL FIELD The present invention relates to a coil component, and more particularly to a coil component having a structure in which a metal terminal made of a metal plate is attached to a drum-shaped core.

An interesting technology for the present invention is disclosed, for example, in Japanese Patent Laying-Open No. 2015-35473 (Patent Document 1). Patent Document 1 describes a coil component having a structure in which a plurality of metal terminals made of metal plates are attached to a drum-shaped core. FIG. 10 is cited from Patent Document 1 and corresponds to FIG. 1 in Patent Document 1. FIG.

A coil component 61 shown in FIG. 10 constitutes a common mode choke coil, and includes a drum-shaped core 62 made of ferrite, for example, and a first wire 63 and a second wire 64 . The drum-shaped core 62 includes a winding core portion (hidden and not shown under the wires 63 and 64) around which the first and second wires 63 and 64 are wound. A first flange portion 65 and a second flange portion 66 are provided at ends opposite to each other in the axial direction.

Two metal terminals 67 and 69 made of metal plates are attached to the first flange portion 65 . Two metal terminals 68 and 70 made of a metal plate are attached to the second collar portion 66 . Note that the metal terminal 70 is hidden behind the second collar portion 66 and is not shown.

A first end of the first wire 63 is connected to a first metal terminal 67 provided on a first collar portion 65 , and a second end opposite to the first end of the first wire 63 is connected to a second collar portion 66 . is connected to a second metal terminal 68 provided on the . A first end of the second wire 64 is connected to a third metal terminal 69 provided on the first collar portion 65, and a second end opposite to the first end of the second wire 64 is connected to the second collar portion 65. It is connected to a fourth metal terminal 70 (not shown) provided on the portion 66 .

How each of the metal terminals 67 to 70 is attached to each of the flanges 65 and 66 will be described.

Each of the flanges 65 and 66 has a bottom surface 71 facing toward the mounting substrate during mounting, an inner end surface 72 facing toward the winding core and on which each end of the winding core is positioned, and a side opposite to the inner end surface 72 . and an outer end surface 73 facing outwards of the .

On the other hand, each of the metal terminals 67 to 70 covers a base portion 74 arranged on the side of the bottom surface 71 of each of the flange portions 65 and 66, and a ridge portion from the base portion 74 where the bottom surface 71 and the outer end surface 73 intersect. and a rising portion 76 extending through the bent portion 75 and arranged on the outer end surface 73 side of each of the collar portions 65 and 66 .

An adhesive is used to secure each of the metal terminals 67-70 to each of the collars 65 and 66. FIG. The adhesive is applied to portions where the rising portions 76 of the metal terminals 67 to 70 and the outer end surfaces 73 of the flanges 65 and 66 face each other.

JP 2015-35473 A

In the structure described in Patent Document 1, the adhesive is usually cured while the rising portion 76 is kept pressed toward the outer end surface 73, so that the adhesive has a thin and uniform thickness. to achieve a strong adhesive state.

As described above, the coil component 61 having a structure in which the first to fourth metal terminals 67 to 70 made of metal plates are attached to the drum-shaped core 62 via an adhesive is soldered to a mounting substrate such as a printed circuit board. When subjected to a heat cycle in a mounted state by attachment or the like, the adhesive portion between at least one of the first to fourth metal terminals 67 to 70 and the drum-shaped core 62 may come off.

This is because the mounting substrate and the drum-shaped core 62 made of ferrite differ greatly in the amount of expansion and contraction during heat cycles. That is, when subjected to a heat cycle, the drum-shaped core 62 made of ferrite does not expand and contract so much, but the mounting board expands and contracts more than that. Since the first to fourth metal terminals 67 to 70 try to follow the behavior of the mounting board, the first metal terminal 67 and the third metal terminal 69 attached to the first collar portion 65 side and the second The distance between the second metal terminal 68 and the fourth metal terminal 70 attached to the collar portion 66 side changes relatively greatly. As a result, the adhesive layer that bonds the metal terminals 67 to 70 and the drum-shaped core 62 may crack, and the crack may cause the bonded portion to come off.

SUMMARY OF THE INVENTION Accordingly, an object of the present invention is to provide a coil component that is less likely to peel off at the bonded portion between the metal terminal and the drum-shaped core even due to heat cycles applied while mounted on a mounting substrate. is.

The present invention provides a drum-shaped core having a core portion extending in the axial direction and a first flange portion and a second flange portion provided at opposite ends of the core portion in the axial direction, and a core portion. A coil component comprising: a wound wire; and a plurality of metal terminals made of metal plates electrically connected to ends of the wire and attached to a first collar portion and a second collar portion, respectively. directed to.

Each of the first flange portion and the second flange portion extends parallel to the axial direction and has a bottom surface directed toward the mounting substrate during mounting, and a bottom surface facing in a direction opposite to the core portion side and with respect to the axial direction. It has outer end faces extending in transverse directions. On the other hand, the plurality of metal terminals has a base portion extending along the bottom surface of the first or second collar portion and a rising portion extending along the outer end surface of the first or second collar portion.

In the coil component according to the present invention, the plurality of metal terminals includes first metal terminals and second metal terminals. In the coil component according to the present invention, a first adhesive layer provided in contact with both at least a portion of the rising portion of the first metal terminal and at least a portion of the outer end face of the first flange portion; A second adhesive layer provided in contact with both at least a portion of the rising portion of the second metal terminal and at least a portion of the outer end surface of the second collar portion.

In the first aspect of the present invention, in the first metal terminal, by bending the metal plate that constitutes the first metal terminal, a portion of the surface facing the outer end surface of the rising portion is provided with the outer end surface. A sloped surface forming a slope is formed, and the thickest portion of the first adhesive layer measured in the axial direction is located on the side of the wider spacing between the sloped surface and the outer end surface.

In a second aspect of the present invention, the first metal terminal has an inclined surface in which the entire surface of the rising portion facing the outer end surface forms an inclination with respect to the outer end surface, and the first metal terminal , a concave portion is provided in a portion of the surface of the rising portion facing the outer end surface, and the thickest portion of the first adhesive layer measured in the axial direction is positioned within the concave portion.

In order to solve the technical problem described above, the first adhesive layer is characterized in that the thickest portion measured in the axial direction is 13 μm or more.

According to the present invention, the behavior of the dimensional change of the drum-shaped core caused by the heat cycle applied while it is mounted on the mounting board, the metal terminal attached to the first flange and the metal attached to the second flange The stress caused by the difference between the behavior of the change in the distance from the terminal and the difference between the behavior and the distance is caused in the adhesive layer, but this stress is received at least in the relatively thick portion having a thickness of 13 μm or more of the first adhesive layer, so the adhesion The stress in the agent layer is advantageously distributed in the thickness direction. Therefore, stress in the adhesive layer can be reduced. As a result, according to the coil component according to the present invention, it is possible to prevent peeling of the bonded portion between the metal terminal and the drum-shaped core.

The lower limit of 13 μm for the thickness of the thickest portion of the adhesive layer was determined by experiments described later.

BRIEF DESCRIPTION OF THE DRAWINGS Fig. 1 is a perspective view showing the appearance of a coil component 1 according to a first embodiment disclosed in this specification, where (A) is a view viewed from relatively above and (B) is a view viewed from relatively below; . 2 is an enlarged cross-sectional view taken along line AA in FIG. 1, showing an attachment portion of a first metal terminal 16 to a first flange portion 6 in the coil component 1 shown in FIG. 1; FIG. FIG. 4 is a diagram showing the relationship between the thickness of the adhesive layer and the rate of change in terminal strength before and after the heat cycle test, which is the basis for determining the lower limit of 13 μm for the thickness of the thickest portion of the adhesive layer. 3 is a cross-sectional view for explaining an example of a method of attaching first and second metal terminals 16 and 17 to first collar portion 6 shown in FIG. 2; FIG. FIG. 3 is an enlarged cross-sectional view corresponding to FIG. 2 for describing a second embodiment disclosed in this specification; 3 is an enlarged cross-sectional view corresponding to FIG. 2 for describing a third embodiment disclosed in this specification; FIG. It is an enlarged cross-sectional view corresponding to FIG. 2 for describing a fourth embodiment disclosed in this specification. FIG. 11 is an enlarged cross-sectional view corresponding to FIG. 2 for describing a fifth embodiment disclosed in this specification; FIG. 11 is a perspective view showing the appearance of a coil component 1a according to a sixth embodiment disclosed in this specification; FIG. 3 is a perspective view showing the appearance of a coil component 61 described in Patent Document 1;

A coil component 1 according to a first embodiment disclosed in this specification, which serves as a reference example of the present invention, will be described with reference to FIGS. 1 and 2. FIG. A coil component 1 shown in FIG. 1 constitutes, for example, a common mode choke coil. In addition, in FIG. 1, illustration of the main part of two wires is abbreviate|omitted.

A drum-shaped core 2 provided in the coil component 1 arranges a first wire 3 and a second wire 4 to be wound. A first brim portion 6 and a second brim portion 7 are provided at ends opposite to each other. The drum-shaped core 2 is preferably made of ferrite. The drum-shaped core 2 may be made of a non-conductive material other than ferrite, such as a non-magnetic material such as alumina, or a resin containing ferrite powder or metal magnetic powder.

The winding core 5 and the first and second flanges 6 and 7 provided in the drum-shaped core 2 have, for example, a quadrangular prism shape having a quadrangular cross-sectional shape. Moreover, although not shown, the ridgeline portions of the quadrangular prism-shaped winding core 5 and the first and second flanges 6 and 7 are preferably chamfered. The cross-sectional shapes of the core portion 5 and the first flange portion 6 and the second flange portion 7 may be rectangular, polygonal such as hexagonal, circular, elliptical, or any combination thereof. may be

The first flange portion 6 has a bottom surface 8 that extends parallel to the axial direction D and faces the mounting board during mounting, and a top surface 10 that faces in the opposite direction to the bottom surface 8 . The first flange portion 6 also has an inner end surface 12a which is a surface rising from the bottom surface 8 and which extends in a direction perpendicular to the mounting substrate, facing toward the core portion 5 side, and an inner end surface 12a facing toward the core portion 5 side. and a first side surface 12c and a second side surface 12d connecting between the inner end surface 12a and the outer end surface 12b. Here, the orthogonal direction includes the case of being strictly orthogonal to the mounting substrate, and also the case of extending while forming a certain angle with respect to the orthogonal direction.

The second flange portion 7 is the same as the first flange portion 6, and has a bottom surface 9 that is parallel to the axial direction D and faces the mounting board during mounting, and a top surface 11 that faces in the opposite direction to the bottom surface 9. ,have. The second flange portion 7 also has an inner end surface 13a which is a surface rising from the bottom surface 9 and which extends in a direction orthogonal to the mounting board and which faces the core portion 5 side, and an inner end surface 13a which faces the core portion 5 side. and a first side surface 13c and a second side surface 13d connecting between the inner end surface 13a and the outer end surface 13b.

Note that the stepped portions protruding along the upper sides of the outer end surfaces 12b and 13b of the flanges 6 and 7 are not an essential feature and may not be formed.

A first metal terminal 16 and a third metal terminal 18 are attached to the first collar portion 6 with a space therebetween. A second metal terminal 17 and a fourth metal terminal 19 are attached to the second collar portion 7 with a space therebetween. The first to fourth metal terminals 16 to 19 are usually manufactured by processing a metal plate made of a copper-based alloy such as phosphor bronze or tough pitch copper. The metal plate, which is the material of the first to fourth metal terminals 16 to 19, is preferably plated with tin. The metal plate has a thickness of, for example, 0.10 mm or more and 0.15 mm or less.

Each of the first metal terminal 16 and the third metal terminal 18 has, as shown in FIG. and a rising portion 23 extending along the outer end surface 12b of the first collar portion 6, which is connected via a bent portion 22 covering a ridge line portion 21 where the bottom surface 8 and the outer end surface 12b of the first collar portion 6 intersect. Each of the first metal terminal 16 and the third metal terminal 18 is further formed with a connection piece 24 extending from the base portion 20 .

Although FIG. 1 only shows a part of each of the second metal terminal 17 and the fourth metal terminal 19, the first metal terminal 16 and the fourth metal terminal 19 have the same shape. The second metal terminal 17 and the above-described third metal terminal 18 have the same shape. Accordingly, the reference numerals 20, 22, 23 and 24 used to denote the base portion, bent portion, rising portion and connecting piece, respectively, of the first metal terminal 16 and the third metal terminal 18 described above are, as appropriate, It will also be used to refer to corresponding portions in second metal terminal 17 and fourth metal terminal 19, respectively.

A first end of the first wire 3 is electrically connected to the connecting piece 24 of the first metal terminal 16 . A second end opposite to the first end of the first wire 3 is electrically connected to the connecting piece 24 of the second metal terminal 17 . A first end of the second wire 4 is electrically connected to the connecting piece 24 of the third metal terminal 18 . A second end opposite to the first end of the second wire 4 is electrically connected to the connecting piece 24 of the fourth metal terminal 19 . Laser welding, for example, is applied to these electrical connections. FIG. 1 shows a hemispherically rising weld mass 25 formed by laser welding.

The first wire 3 and the second wire 4 generally have a circular cross section, and have a linear central conductor and an insulating film made of an electrically insulating resin covering the peripheral surface of the central conductor. The diameter of the central conductor is, for example, 28 μm or more and 50 μm or less. Moreover, the thickness of the insulating coating is, for example, 3 μm or more and 6 μm or less. The central conductor is made of, for example, a highly conductive metal such as copper, silver or gold. The insulating film is made of a resin containing at least imide bonds, such as polyamide-imide or imide-modified polyurethane.

Although not shown in FIG. 1, the first wire 3 and the second wire 4 are spirally wound around the winding core 5 in the same direction. More specifically, even if the first wire 3 and the second wire 4 are wound in two layers such that one of them is on the inner layer side and the other is on the outer layer side, the axis line of the winding core portion 5 is A bifilar winding may be employed in which the turns are arranged alternately in the direction and wound in the same direction.

The first and third metal terminals 16 and 18 are attached to the first collar 6 with an adhesive, and the second and fourth metal terminals 17 and 19 are attached to the second collar 7 with an adhesive. Details of these mounting portions are described below with reference to FIG. 2, which is a cross-section along line AA of FIG. FIG. 2 shows the attachment portion of the first metal terminal 16 to the first flange portion 6 . Since the mounting portions of the second to fourth metal terminals 17 to 19 are substantially the same as the mounting portion of the first metal terminal 16, detailed description thereof will be omitted.

As shown in FIG. 2, a first adhesive layer 26a made of the adhesive described above is formed in contact with both the rising portion 23 of the first metal terminal 16 and the outer end face 12b of the first flange portion 6. ing. The second adhesive layer 26b, the third adhesive layer 26c, and the fourth adhesive layer 26d provided in association with the second metal terminal 17, the third metal terminal 18, and the fourth metal terminal 19, respectively, are also It has the same form as the one adhesive layer 26a. Of these adhesive layers 26b-26d, only the second adhesive layer 26b is illustrated in FIG. 4 described later, and the third adhesive layer 26c and the fourth adhesive layer 26d are not illustrated in any of the drawings. For convenience, they will be referenced 26c and 26d. Epoxy-based adhesives, for example, are used as adhesives forming the first to fourth adhesive layers 26a to 26d. The epoxy adhesive may contain filler such as silica particles. In this way, the adhesive contains hard particles such as silica particles and has a large particle size, so that the thickness of the adhesive layer can be ensured.

In this embodiment, the bottom surface 8 of the first flange portion 6 and the outer end surface 12b are perpendicular to each other, and the rising portion 23 of the first metal terminal 16 is flat. A surface of the rising portion 23 facing the outer end face 12b forms a sloped surface 29 forming a slope with respect to the outer end face 12b. More specifically, the base portion 20 and the rising portion 23 of the first metal terminal 16 are connected via a bent portion 22 that covers a ridgeline portion 21 where the bottom surface 8 and the outer end surface 12b of the first collar portion 6 intersect. The entire surface of the rising portion 23 facing the outer end surface 12b is a sloped surface 29. As shown in FIG.

The interior angle formed by the base portion 20 and the rising portion 23 at the bent portion 22 is an acute angle, more specifically, 70 degrees or more and less than 90 degrees. Therefore, the first adhesive layer 26a forms the thickest portion on the side of the rising portion 23 closer to the bent portion 22 and on the side where the distance between the sloped surface 29 and the outer end surface 12b is wider. The thickness T of the thickest portion of the first adhesive layer 26a measured in the axial direction D is 13 μm or more, preferably 19 μm or more. These lower limit values of the thickness T are obtained from the data shown in FIG. 3, which will be described later. It should be noted that the bent portion 22 may not actually be bent at a constant angle due to manufacturing variations or differences in quality. For example, there are curved portions and portions with different angles.

In conventional coil components, cracks that cause peeling of the adhesive part due to heat cycles when mounted on a mounting substrate grow as the number of heat cycles increases, and that cracks progress from the tip side of the rising portion to the base portion. It was found that there is a phenomenon of progressing in the direction.

Contrary to the latter phenomenon, according to this embodiment, the thickest part of the first adhesive layer 26a is located closer to the base 20, so that the first adhesive layer 26a does not adhere to the first adhesive layer 26a at the final stage when the crack has finished progressing. The stress exerted on layer 26a is advantageously distributed. Therefore, it is possible to prevent cracks from completely progressing in the first adhesive layer 26a, thereby preventing the adhesive force from becoming zero.

In addition, as in this embodiment, at least part of the rising portions 23 of the first to fourth metal terminals 16 to 19 and at least one of the outer end faces 12b and 13b of the first flange portion 6 and the second flange portion 7 are provided. When the first to fourth adhesive layers 26a to 26d are provided in contact with both of the parts, the heat cycle exerts a force in the peeling direction on the first to fourth adhesive layers 26a to 26d. will be Such peeling force acts in the thickness direction of the first to fourth adhesive layers 26a to 26d. Therefore, the greater the thickness of the first to fourth adhesive layers 26a to 26d, the higher the resistance to force in the peeling direction.

On the other hand, it is presumed that the first to fourth adhesive layers 26a to 26d on the tip 23a side of the rising portion 23, which have relatively small dimensions in the thickness direction, contribute to the improvement of the adhesive strength.

3 and Table 1 show the relationship between the thicknesses of the first to fourth adhesive layers 26a to 26d and the rate of change in terminal strength of the coil component 1 with respect to the mounting substrate after the heat cycle test. The "terminal strength" is the strength measured when the component is pressed parallel to the board while soldered to the mounting board. An epoxy-based adhesive was used as the adhesive for forming the first to fourth adhesive layers 26a to 26d. In the heat cycle test, an environmental condition was applied in which temperature fluctuations from -55°C to 150°C were repeated for 1000 cycles. The rate of change in terminal strength is obtained by determining the rate of decrease in terminal strength after the heat cycle test based on the terminal strength before the heat cycle test. It should be noted that the decrease in terminal strength with respect to the mounting substrate corresponds to the occurrence of peeling of the first to fourth adhesive layers 26a to 26d as a phenomenon.

Referring to FIG. 3 and Table 1, as the thicknesses of the first to fourth adhesive layers 26a to 26d increase, the absolute value of the rate of change in terminal strength tends to decrease. , when the thickness of the first to fourth adhesive layers 26a to 26d is 13 μm or more, the absolute value of the terminal strength change rate is 40% or less. The effect of conspicuously suppressing the decrease in terminal strength begins to appear. Furthermore, when the thickness of the first to fourth adhesive layers 26a to 26d is 19 μm or more, there are no samples in which the absolute value of the rate of change in terminal strength greatly exceeds 30%, thereby reliably suppressing a decrease in terminal strength. be done.

Based on the above results, the thickness T of the thickest portions of the first to fourth adhesive layers 26a to 26d is determined to be 13 μm or more, more preferably 19 μm or more, as described above.

The upper limit of the thickness T of the thickest portions of the first to fourth adhesive layers 26a to 26d is set to 100 μm, more preferably to 70 μm, so that a normal bonding process can be performed without hindrance. .

As shown in FIG. 2, no adhesive is applied between the bottom surface 8 of the first collar 6 and the base 20 of the first metal terminal 16, but adhesive may be applied here. This also applies to other embodiments described later. When the adhesive is applied between the bottom surface 8 of the first collar portion 6 and the base portion 20 of the first metal terminal 16, the adhesive layer formed here is subjected to a force in the shear direction during heat cycles. be Thus, the thickness of the adhesive layer to which shear force is applied may be less than 13 μm.

In order to obtain the structure shown in FIG. 2, it is preferable that the first to fourth metal terminals 16 to 19 before the bonding process have an acute internal angle between the base portion 20 and the rising portion 23, more specifically, is 70 degrees or more and less than 90 degrees. FIG. 4 shows a cross-sectional view of a portion of hoop member 37 made of a metal plate on which portions to become first metal terminal 16 and second metal terminal 17 are formed. In FIG. 4, the portions to be the third metal terminal 18 and the fourth metal terminal 19 are hidden behind the portions to be the first metal terminal 16 and the second metal terminal 17 and are not shown. The hoop material 37 has its longitudinal direction perpendicular to the plane of FIG.

For example, an epoxy-based adhesive is applied to predetermined regions of the rising portions 23 of the portions to be the first to fourth metal terminals 16 to 19 held by the hoop material 37, and then the drum-shaped core 2 is attached to the second metal terminals 16 to 19. It is arranged between the first metal terminal 16 and the second metal terminal 17 and between the third metal terminal 18 and the fourth metal terminal 19 . The epoxy-based adhesive described above is to be adhesive layers 26a-26d provided between each of the first to fourth metal terminals 16-19 and the drum-shaped core 2. As shown in FIG. The drum-shaped core 2 is held by the elastic force exerted by the first and third metal terminals 16 and 18 and the second and fourth metal terminals 17 and 19 sandwiching it. In this state, the internal angle between the base portion 20 and the rising portion 23 of the portions to be the first to fourth metal terminals 16 to 19 is maintained at 70 degrees or more and less than 90 degrees.

Although not shown, the hoop member 37 holds a large number of drum-shaped cores 2 distributed at equal intervals along the longitudinal direction thereof. Such hoop material 37 is then cut into lengths holding about 20 drum-like cores 2 .

Next, the cut hoop material 37 is placed in an oven and heated, for example, at a temperature of 130° C. or more and 170° C. or less for a time of 30 minutes or more and 60 minutes or less to cure the adhesive. Thereby, the first to fourth adhesive layers 26a to 26d are formed.

After that, portions to be the first to fourth metal terminals 16 to 19 are cut off from the hoop material 37 and taken out together with the drum-shaped core 2 . Then, a step of winding the first and second wires 3 and 4 around the winding core 5 and connection pieces 24 (see FIG. 1) is performed.

Thus, a coil component 1 having a structure as shown in FIG. 1 is obtained.

Conventionally, in order to form an adhesive layer having a thin and uniform thickness and to achieve a stronger bonding state, the rising portion of the metal terminal is pressed relatively strongly toward the outer end surface of the flange portion in the bonding process. , while maintaining this state, the adhesive is cured. When contacting 12b and 13b, the interior angle formed by the base portion 20 and the rising portion 23 is maintained at 70 degrees or more and 110 degrees or less. Therefore, as long as this state is maintained, the rising portions 23 of the first to fourth metal terminals 16 to 19 may be pressed against the outer end surfaces 12b and 13b of the first flange portion 6 and the second flange portion 7. Alternatively, only the tip 23a of the rising portion 23 may be pressed.

The coil component 1 may further include a plate-like core 42 extending between the top surface 10 of the first flange portion 6 and the top surface 11 of the second flange portion 7, as shown in FIG. The plate-shaped core 42 is also preferably made of ferrite, similarly to the case of the drum-shaped core 2 . Moreover, the plate-shaped core 42 may be made of a non-conductive material other than ferrite, such as a non-magnetic material such as alumina, or a resin containing ferrite powder or metal magnetic powder.

The plate-shaped core 42 is adhered to the top surface 10 of the first flange portion 6 and the top surface 11 of the second flange portion 7 with an adhesive (not shown). Thereby, the plate-shaped core 42 can cooperate with the drum-shaped core 2 to form a closed magnetic circuit. As the adhesive, for example, one made of epoxy resin or one containing silica filler is used. In order to narrow the gap between the plate-shaped core 42 and the first and second flanges 6 and 7 as much as possible, it is preferable to use an adhesive that does not contain filler.

Other embodiments disclosed in this specification will now be described with reference to FIGS. 5 to 8 are diagrams corresponding to FIG. 2, showing the attachment portion of the first metal terminal 16 to the first flange portion 6. FIG. Since the mounting portions of the second to fourth metal terminals 17 to 19 are substantially the same as the mounting portion of the first metal terminal 16, description thereof will be omitted. 5 to 8, the elements corresponding to the elements shown in FIG. 2 are denoted by the same reference numerals, and overlapping descriptions are omitted.

The second embodiment shown in FIG. 5 is a reference example having some of the characteristics of the present invention. A concave portion 27 is provided on a part of the surface in contact with, more specifically, on the base portion 20 side of the surface in contact with the first adhesive layer 26a. Accordingly, the portion of the first adhesive layer 26 a having the greatest thickness T is positioned within the recess 27 . In this way, the provision of the concave portion 27 facilitates the formation of the thickest portion of the first adhesive layer 26a with the thickness T. As shown in FIG.

Here, the thickness T of the thickest portion of the first adhesive layer 26a is, as described above, set to 13 μm or more, and more preferably set to 19 μm or more. The upper limit of the thickness T of the thickest portion of the first adhesive layer 26a is 100 μm, more preferably 70 μm, so that a normal bonding process can be carried out without any trouble.

In the following description, the thickness T refers to the thickness that satisfies all of the above conditions.

The formation of the concave portion 27 in the rising portion 23 described above can be realized by thinning a portion of the rising portion 23, for example, by coining. Further, the formation of the concave portion 27 may be realized by, for example, embossing, which extrudes part of the rising portion 23 .

The third embodiment shown in FIG. 6 is a reference example having some of the features of the present invention. Contrary to the case of the first embodiment, the first adhesive layer 26a has the thickest portion T located farther from the base portion 20, that is, on the tip 23a side of the rising portion 23. As shown in FIG.

More specifically, the bottom surface 8 of the first collar portion 6 and the outer end surface 12b are perpendicular to each other, and the rising portion 23 of the first metal terminal 16 is flat. The entire surface of the rising portion 23 facing the outer end surface 12b forms a sloped surface 30 forming a slope with respect to the outer end surface 12b. The interior angle formed by the base portion 20 and the rising portion 23 at the bent portion 22 is an obtuse angle, more specifically, greater than 90 degrees and less than or equal to 110 degrees. Therefore, the first adhesive layer 26a forms the thickest portion having a thickness T on the side of the rising portion 23 closer to the tip 23a. As in the case described above, the bent portion 22 may actually not be bent at a constant angle due to manufacturing variations or quality differences. Some parts are different.

In contrast to the above-described phenomenon that cracks that cause peeling of the bonded portion due to the heat cycle while soldered to the mounting substrate progress in the direction from the tip 23a side of the rising portion 23 toward the base portion 20, this phenomenon is counteracted. According to the embodiment, since the portion with the greatest thickness T is located farther from the base portion 20, that is, on the tip 23a side of the rising portion 23, the first adhesive is used in the initial stage when cracks are about to occur. The stress exerted on layer 26a is advantageously distributed. Therefore, cracks are less likely to occur in the first adhesive layer 26a and can be prevented from progressing.

In addition, since the portion of the first adhesive layer 26a closer to the base portion 20 has a relatively smaller dimension in the thickness direction, it is presumed that this contributes to the improvement of the adhesive strength.

The fourth embodiment shown in FIG. 7 is a reference example having some of the characteristics of the present invention. A concave portion 28 is provided on a portion of the surface in contact with the first adhesive layer 26a, more specifically, on the tip 23a side of the rising portion 23 in the surface in contact with the first adhesive layer 26a. Accordingly, the portion of the first adhesive layer 26a having the greatest thickness T is positioned within the recess 28. As shown in FIG. Thus, the presence of the concave portion 28 facilitates the formation of the thickest portion of the thickness T of the first adhesive layer 26a.

Formation of the concave portion 28 in the rising portion 23 described above can be realized by thinning a portion of the rising portion 23, for example, by coining, as in the case of the second embodiment shown in FIG. Formation of recess 28 may be realized by, for example, embossing, which extrudes a portion of rising portion 23 .

The fifth embodiment shown in FIG. 8 is a reference example having some of the characteristics of the present invention. The surface facing the end face 12b extends parallel to the outer end face 12b, and the first adhesive layer 26a has a uniform thickness. In this case, almost the entire area of the first adhesive layer 26a has the thickest thickness T.

Next, a coil component 1a according to a sixth embodiment, which is one embodiment of the present invention, will be described with reference to FIG. Coil component 1a constitutes, for example, a common mode choke coil, but the illustration of two wires and the state after welding of the ends of the wires are omitted. In FIG. 9, the elements corresponding to the elements shown in FIG. 1 are denoted by the same reference numerals, and overlapping descriptions are omitted.

In the sixth embodiment, each of the first metal terminal 16 and the third metal terminal 18 includes a base portion 20 extending along the bottom surface 8 of the first collar portion 6 and a base portion 20 extending along the bottom surface 8 of the first collar portion 6 as in the first embodiment. A rising portion 23 extending along the outer end surface 12b of the first collar portion 6 and connected from the portion 20 via a bent portion 22 covering a ridgeline portion 21 where the bottom surface 8 of the first collar portion 6 and the outer end surface 12b intersect. and have Each of the first metal terminal 16 and the third metal terminal 18 is further formed with a connection piece 24 extending from the base portion 20 .

The surfaces of the first and third metal terminals 16 and 18 facing the outer end surface 12b of the first collar portion 6 in the rising portion 23 are partly sloped surfaces 31. As shown in FIG. More specifically, the first and third metal terminals 16 and 18 protrude at the rising portion 23 in a direction crossing the axial direction of the winding core portion 5 and parallel to the extending direction of the base portion 20. It has a projecting portion 32 . The projecting portion 32 extends in a slightly curved direction with respect to the rest of the rising portion 23 . The sloped surface 31 is formed on the side of the overhang 32 facing the outer end surface 12b.

Although not shown in FIG. 9, the adhesive layer is formed in contact with both the inclined surface 31 of the overhanging portion 32 and the outer end surface 12b. The adhesive layer forms the thickest portion on the side closer to the tip of the projecting portion 32, and its thickness is set to 13 μm or more.

The second metal terminal 17 and the fourth metal terminal 19 attached to the second collar portion 7 are only partially shown in FIG. , and the second metal terminal 17 and the above-described third metal terminal 18 have the same shape. Therefore, the second metal terminal 17 and the fourth metal terminal 19 are formed with the same adhesive layer as the first metal terminal 16 and the third metal terminal 18 described above.

The sixth embodiment can also achieve the same effects as the first embodiment described above.

In the above-described first to sixth embodiments, each of the first metal terminals 16 to 19 has the structure that "the thickest part of the adhesive layer is 13 μm or more, more preferably 19 μm or more." was employed in all of the first through fourth adhesive layers 26a-26d associated with the . It may be employed in one or more of the adhesive layers 26a-26d.

2 and 6, the outer end surfaces 12b and 13b of the flanges 6 and 7 are orthogonal to the bottom surfaces 8 and 9, and the rising portions 23 of the metal terminals 16 to 19 intersects the base portion 20 in a non-orthogonal state, the thickness of the adhesive layers 26a to 26d is 13 μm or more at the thickest portion. 7 intersects the bottom surfaces 8 and 9 in a non-orthogonal manner, and the rising portion 23 of each of the metal terminals 16 to 19 is orthogonal to the base portion 20. A configuration may be realized in which the thickest portions of the agent layers 26a to 26d are 13 μm or more. Further, the outer end surfaces 12b and 13b of the flanges 6 and 7 intersect the bottom surfaces 8 and 9 in a non-perpendicular state, and the rising portions 23 of the metal terminals 16 to 19 are non-orthogonal to the base portion 20. A configuration in which the thickness of the adhesive layers 26a to 26d is 13 μm or more at the thickest portion may be realized by both the configuration in which the adhesive layers 26a to 26d intersect each other in an orthogonal state. In either case, it is possible to obtain the same effects as those of the embodiments shown in FIGS.

Also, the coil component according to the present invention has been described based on a more specific embodiment relating to the common mode choke coil, but this embodiment is illustrative and various other modifications are possible. Therefore, the number of wires provided in the coil component, the winding direction of the wires, the number of metal terminals, and the like can be changed according to the function of the coil component.

In addition, each embodiment described herein is illustrative, and partial substitution or combination of configurations is possible between different embodiments. For example, as shown in FIG. 2 or FIG. 6, the entire surface of the raised portion 23 of the first metal terminal 16 facing the outer end face 12b forms a sloped surface 29 or 30 forming a slope with respect to the outer end face 12b. 5 or 7, a recess 27 or 28 is provided in a portion of the surface facing the outer end surface 12b of the rising portion 23 of the first metal terminal 16. Is possible.

Reference Signs List 1, 1a coil component 2 drum-shaped core 3, 4 wire 5 winding core 6, 7 flange 8, 9 bottom 10, 11 top 12b, 13b outer end 16-19 metal terminal 20 base 21 ridge 22 bend 23 Rising portions 26a, 26b Adhesive layer 27, 28 Concave portions 29, 30, 31 Inclined surface 32 Overhanging portion D Axial direction T Thickness at the thickest portion

Claims (7)

a drum-shaped core having a core portion extending in the axial direction and a first flange portion and a second flange portion provided at opposite ends of the core portion in the axial direction;
a wire wound around the winding core;
a plurality of metal terminals made of metal plates electrically connected to the ends of the wires and respectively attached to the first collar portion and the second collar portion;
with
Each of the first flange portion and the second flange portion has a bottom surface that extends parallel to the axial direction and faces the mounting board during mounting, and a bottom surface that faces in a direction opposite to the winding core portion and faces the axial direction. having an outer end surface extending in a direction that intersects the direction;
The plurality of metal terminals has a base portion extending along the bottom surface of the first or second flange portion and a raised portion extending along the outer end surface of the first or second flange portion. and
the plurality of metal terminals includes a first metal terminal and a second metal terminal;
a first adhesive layer provided in contact with both at least a portion of the rising portion of the first metal terminal and at least a portion of the outer end face of the first brim;
a second adhesive layer provided in contact with both at least a portion of the rising portion of the second metal terminal and at least a portion of the outer end face of the second flange;
further comprising
With respect to the first metal terminal, a part of the surface of the rising portion facing the outer end face is formed with a slope with respect to the outer end face by bending the metal plate that constitutes the first metal terminal. A sloped surface is formed with
the thickest portion of the first adhesive layer measured in the axial direction is located on the side of the wider spacing between the sloped surface and the outer end surface;
The first adhesive layer has a thickness of 13 μm or more at the thickest portion measured in the axial direction.
coil parts. The first metal terminal has a protruding portion protruding in a direction intersecting the axial direction of the winding core portion and parallel to an extending direction of the base portion at the rising portion, 3. The overhanging portion extends in a bent direction with respect to the remaining portion of the rising portion, and the sloped surface is formed on the side of the overhanging portion facing the outer end surface. 2. The coil component according to 1. a drum-shaped core having a core portion extending in the axial direction and a first flange portion and a second flange portion provided at opposite ends of the core portion in the axial direction;
a wire wound around the winding core;
a plurality of metal terminals made of metal plates electrically connected to the ends of the wires and respectively attached to the first collar portion and the second collar portion;
with
Each of the first flange portion and the second flange portion has a bottom surface that extends parallel to the axial direction and faces the mounting board during mounting, and a bottom surface that faces in a direction opposite to the winding core portion and faces the axial direction. having an outer end surface extending in a direction that intersects the direction;
The plurality of metal terminals has a base portion extending along the bottom surface of the first or second flange portion and a raised portion extending along the outer end surface of the first or second flange portion. and
the plurality of metal terminals includes a first metal terminal and a second metal terminal;
a first adhesive layer provided in contact with both at least a portion of the rising portion of the first metal terminal and at least a portion of the outer end face of the first brim;
a second adhesive layer provided in contact with both at least a portion of the rising portion of the second metal terminal and at least a portion of the outer end surface of the second flange;
further comprising
With respect to the first metal terminal, the entire surface of the rising portion facing the outer end surface forms a sloped surface forming a slope with respect to the outer end surface,
a concave portion is provided in a portion of a surface of the rising portion facing the outer end surface of the first metal terminal,
the thickest portion of the first adhesive layer measured in the axial direction is positioned within the recess;
The first adhesive layer has a thickness of 13 μm or more at the thickest portion measured in the axial direction.
coil parts. 4. The coil component according to claim 1, wherein said second adhesive layer has a thickness of 13 [mu]m or more at the thickest portion measured in said axial direction. 5. The coil component according to claim 1, wherein said first adhesive layer has a thickness of 19 [mu]m or more at the thickest portion measured in said axial direction. 6. The coil component according to claim 5, wherein said second adhesive layer has a thickness of 19 [mu]m or more at the thickest portion measured in said axial direction. 7. The coil component according to claim 1, wherein said first adhesive layer and said second adhesive layer contain an epoxy adhesive.

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