Coil component

Abstract

Provided is a coil component having improved fixing force of a core material to a plate member, low magnetic resistance, and good product characteristics. The coil component includes: a core material having a winding core portion, a first flange portion provided at a first end portion of the winding core portion, and a second flange portion provided at a second end portion of the winding core portion; a wire wound around the winding core portion of the core material; a plate member provided across the first flange portion and the second flange portion; an adhesive portion provided between the first flange portion and the plate member to adhere the first flange portion and the plate member, and an adhesive portion provided between the second flange portion and the plate member to adhere the second flange portion and the plate member; the adhesive portion contains a resin and a magnetic powder, the magnetic powder contains first particles having a particle diameter of 0.1 μm to 2.0 μm and second particles having a particle diameter of 3.0 μm to 8.0 μm, the proportion of the number of the first particles to the total number of particles of the magnetic powder is 0.11 to 0.80, the proportion of the number of the second particles to the total number of particles of the magnetic powder is 0.19 to 0.89, the total of the number of the first particles and the number of the second particles relative to the total number of particles of the magnetic powder is 0.84 or more, and the proportion of the area of the magnetic powder to the area of the adhesive portion in a cross section of the adhesive portion is 25.0% or more.

Description

TECHNICAL FIELD

[0001] The present disclosure relates to a coil member. BACKGROUND

[0002] In the past, with respect to a coil member, a coil member is described in Japanese Patent Application Publication No. 2015-65272 (Patent Literature 1). The coil member has a core material, a plate member, and a wire wound around the core material, and the core material and the plate member are fixed by providing an adhesive between the wire and the plate member.

[0003] PRIOR ART DOCUMENTS

[0004] PATENT LITERATURE

[0005] Patent Literature 1: Japanese Patent Application Publication No. 2015-65272 SUMMARY

[0006] However, when an adhesive is provided on the wire as in Patent Literature 1, the adhesive area cannot be ensured, and sometimes the fixing force of the core material and the plate member decreases.

[0007] Therefore, an object of the present disclosure is to provide a coil member in which the fixing force of a core material and a plate member is improved, and which has low magnetic resistance and good product characteristics.

[0008] To solve the above problem, the coil member of the present disclosure has:

[0009] a core material having a winding core portion, a first flange portion provided at a first end portion of the winding core portion, and a second flange portion provided at a second end portion of the winding core portion,

[0010] a wire wound around the winding core portion of the core material,

[0011] a plate member provided across the first flange portion and the second flange portion,

[0012] an adhesive portion provided between the first flange portion and the plate member, which adheres the first flange portion and the plate member, and an adhesive portion provided between the second flange portion and the plate member, which adheres the second flange portion and the plate member,

[0013] the adhesive portion contains a resin and a magnetic powder,

[0014] the magnetic powder contains first particles having a particle diameter in the range of 0.1 μm to 2.0 μm and second particles having a particle diameter in the range of 3.0 μm to 8.0 μm,

[0015] the proportion of the number of the first particles to the total number of particles of the magnetic powder is in the range of 0.11 to 0.80,

[0016] The proportion of the number of the second particles to the total number of the magnetic powder is in the range of 0.19 to 0.89,

[0017] The proportion of the total number of the first particles and the second particles to the total number of the magnetic powder is 0.84 or more,

[0018] In the cross section of the adhesive portion, the proportion of the area of the magnetic powder to the area of the adhesive portion is 25.0% or more.

[0019] With the above configuration, the first flange portion and the plate member and the second flange portion and the plate member are adhered by the adhesive portion, and thus the adhesive area can be ensured. By the adhesive portion containing the magnetic powder satisfying the above conditions, the magnetic resistance of the coil member can be reduced, and the adhesion can also be ensured. Thus, the improvement of the fixing force and the improvement of the product characteristics can be achieved.

[0020] In one embodiment of the coil member, the magnetic permeability μ' of the adhesive portion at 1 MHz is 4.6 or more.

[0021] With the above configuration, the magnetic resistance of the coil member can be reduced, and the product characteristics can be improved.

[0022] In one embodiment of the coil member, the proportion of the area of the magnetic powder is 35.1% or more.

[0023] With the above configuration, the proportion of the area of the magnetic powder of the adhesive portion can be increased, and the magnetic resistance can be further reduced.

[0024] In one embodiment of the coil member, the proportion of the total number of the first particles and the second particles is 0.90 or more.

[0025] With the above configuration, the adhesion of the core material and the plate member can be ensured, and the magnetic resistance of the coil member can be reduced, and the product characteristics can be improved.

[0026] In one embodiment of the coil member, in at least one of the interval between the first flange portion and the plate member and the interval between the second flange portion and the plate member, there is a first portion having a narrow interval and a second portion having a wider interval than the first portion.

[0027] Here, the first portion is a portion including the smallest interval, and the second portion is a portion including the largest interval.

[0028] With the above configuration, by providing the first portion, the magnetic resistance of the coil member can be reduced, and by providing the second portion, the adhesion of the core material and the plate member can be improved.

[0029] Further, in one embodiment of the coil component, the interval of the first portion is in the range of 1 μm to 10 μm, and the interval of the second portion is in the range of 5 μm to 20 μm.

[0030] With the above configuration, the magnetic resistance of the coil component can be reduced, and the adhesion of the core material to the plate member can be further improved.

[0031] Further, in one embodiment of the coil component, the first particles are present more in the first portion than in the second portion.

[0032] With the above configuration, the magnetic particles can be moderately present in the first portion.

[0033] Further, in one embodiment of the coil component, the second particles are present more in the second portion than in the first portion.

[0034] With the above configuration, the magnetic particles can be moderately present in the second portion.

[0035] Further, in one embodiment of the coil component, the first portion is present on the side of the winding core portion.

[0036] With the above configuration, the magnetic path length is shortened, and as a result, the inductance value can be increased.

[0037] With the coil component of the present disclosure, the fixing force of the core material to the plate member is improved, and the magnetic resistance can be reduced, and the product characteristics can be improved. BRIEF DESCRIPTION OF DRAWINGS

[0038] Figure 1 is a front view showing a first embodiment of the coil component of the present disclosure.

[0039] Figure 2 is a side view of the coil component of Figure 1

[0040] Figure 3 is a scanning electron microscope (SEM) image showing a cross-sectional state of the adhesive portion.

[0041] Figure 4 is a plan view showing a second embodiment of the coil component of the present disclosure.

[0042] Figure 5 is a cross-sectional view showing the second embodiment of the coil component of the present disclosure.

[0043] Figure 6 is a cross-sectional view showing a third embodiment of the coil component of the present disclosure.

[0044] Figure 7 ​is a cross-sectional view showing a coil member of the fourth embodiment of the present disclosure.

[0045] Figure 8 is a cross-sectional view showing a coil member of the fifth embodiment of the present disclosure.

[0046] Explanation of symbols

[0047] 1, 1A, 1B, 1C, 1D Coil member

[0048] 2, 2a, 2c, 2d Core material

[0049] 3 Winding core portion

[0050] 4, 4a, 4c, 4d First flange portion

[0051] 5 Second flange portion

[0052] 41, 51 Inner surface

[0053] 42, 52 Outer surface

[0054] 43, 43a, 43c, 43d, 53 Upper surface

[0055] 44, 54 Lower surface

[0056] 13, 14 First terminal electrode, second terminal electrode

[0057] 15 Wire

[0058] 6, 6b, 6c Plate member

[0059] 61 First main surface

[0060] 62, 62b, 62c Second main surface

[0061] 7, 7a, 7b, 7c, 7d Bonding portion DETAILED DESCRIPTION

[0062] Hereinafter, a coil member of one embodiment of the present disclosure will be described in detail through illustrated embodiments. Note that the drawings attached hereto include part of a schematic view and do not always reflect actual dimensions and ratios.

[0063] (First Embodiment)

[0064] Figure 1 is a front view showing the coil member 1 of the first embodiment of the present disclosure, Figure 2 is a side view showing the coil member 1 as viewed from the direction of the first flange portion.

[0065] As shown in Figure 1 and 2 , the coil member 1 includes a core material 2, a plate member 6, and a bonding portion 7 that bonds the core material 2 and the plate member.

[0066] The core material 2 has a core portion 3, a first flange portion 4 provided at a first end portion of the core portion 3, and a second flange portion 5 provided at a second end portion of the core portion 3. The core material 2 is composed of, for example, a magnetic material such as ferrite.

[0067] The first flange portion 4 has an inner surface 41 facing the core portion, an outer surface 42 facing the opposite side from the inner surface, an upper surface 43 connecting the inner surface 41 and the outer surface 42, and a lower surface 44 facing the opposite side from the upper surface 43. Note that the upper surface 43 is a surface facing the board member 6.

[0068] The second flange portion 5 has an inner surface 51 facing the core portion, an outer surface 52 facing the opposite side from the inner surface, an upper surface 53 connecting the inner surface 51 and the outer surface 52, and a lower surface 54 facing the opposite side from the upper surface 53. Note that the upper surface 53 is a surface facing the board member 6.

[0069] The first terminal electrode 13 is provided on the lower surface 44 of the first flange portion 4, and the second terminal electrode 14 is provided on the lower surface 54 of the second flange portion 5. The first terminal electrode 13 and the second terminal electrode 14 are formed, for example, by printing a conductive paste containing a conductive metal powder such as Ag powder, and then sintering it, and further performing Ni plating and Sn plating. Alternatively, the terminal electrodes 13 and 14 can be formed, for example, by attaching a conductive metal sheet composed of a copper-based metal such as tough copper or phosphor bronze to the first flange portion 4 and the second flange portion 5.

[0070] The core portion 3 has a center axis extending in a direction connecting the first flange portion 4 and the second flange portion 5. The wire 15 is wound around the core portion 3 along the center axis of the core portion.

[0071] The wire 15 is formed, for example, of a Cu wire insulated by a resin such as polyurethane, polyester imide, or polyamide imide. One end of the wire 15 is electrically connected to the first terminal electrode 13, and the other end is electrically connected to the second terminal electrode 14. The connection of the first terminal electrode 13 and the second terminal electrode 14 to the wire 15 is performed, for example, using thermal compression bonding, ultrasonic welding, laser welding, or the like.

[0072] Further, hereinafter, the lower surface 44 of the first flange portion 4 is positioned on the side on which the mounting substrate is mounted. The axial direction of the core portion 3 is referred to as the L direction, the direction orthogonal to the L direction on the lower surface 44 of the first flange portion 4 is referred to as the W direction, and the direction opposite to the upper surface 43 of the first flange portion 4 is referred to as the T direction. The T direction is orthogonal to the L direction and the W direction. The positive direction of the T direction is referred to as the upward direction, and the negative direction of the T direction is referred to as the downward direction. In other words, the lower surface 44 of the first flange portion 4 corresponds to the downward direction, and the upper surface 43 of the first flange portion 4 corresponds to the upward direction. The L direction is also referred to as the length direction of the core material 2, the W direction is also referred to as the width direction of the core material 2, and the T direction is also referred to as the height direction of the core material 2.

[0073] The plate member 6 is provided so as to straddle the first flange portion 4 and the second flange portion 5. The plate member 6 has a first main surface 61 and a second main surface 62 facing the side opposite to the first main surface. The plate member 6 is also composed of a magnetic material such as ferrite, like the core material 2, and thus the plate member 6 cooperates with the core material 2 to constitute a closed magnetic circuit.

[0074] The plate member 6 opposes the upper surface 43 of the first flange portion 4 and the upper surface 53 of the second flange portion 5 of the core material 2 on the second main surface 62.

[0075] The adhesive portion 7 is provided between the first flange portion 4 of the core material 2 and the plate member 6 to adhere the first flange portion 4 and the plate member 6, and is provided between the second flange portion 5 and the plate member 6 to adhere the second flange portion 5 and the plate member 6. That is, the adhesive portion 7 is provided between the upper surface 43 of the first flange portion 4 and the second main surface 62 of the plate member 6, and between the upper surface 53 of the second flange portion 5 and the second main surface 62 of the plate member 6. Since the first flange portion 4 and the plate member 6 and the second flange portion 5 and the plate member 6 are adhered, the adhesive area of the core material 2 and the plate member 6 can be ensured. In the past, the upper surface of the flange portion was polished or the like to bring the core material and the plate member into contact, but in the present disclosure, since the adhesive portion 7 is provided, the polishing or the like process can be omitted.

[0076] It is preferable that the adhesive portion 7 not be provided between the core portion 3 of the core material 2 and the plate member 6. By being in this form, even when an external force is applied to the plate member 6, the external force does not directly pass to the wire 15 wound around the core portion 3, and deformation of the wire 15 can be suppressed, and wire breakage of the wire 15 can be suppressed.

[0077] The adhesive portion 7 contains a resin and a magnetic powder.

[0078] The resin adheres the first flange portion 4 and the plate member 6 and the second flange portion 5 and the plate member 6.

[0079] As the resin, a curable resin, a moldable resin, a rubber, an elastomer, or the like can be used. From the viewpoint of heat resistance, the resin is preferably a curable resin such as a thermosetting resin, an ultraviolet-curable resin, for example, an epoxy-based resin, a silicone-based resin, a phenol-based resin, a melamine-based resin, or the like.

[0080] For example, when the resin is an epoxy-based resin, as a raw material for forming the resin, a bisphenol F-type epoxy resin, a bisphenol A-type epoxy resin, a phenoxy-type epoxy resin, or the like can be used, and as a curing agent, an amine-based curing agent such as dicyandiamide, an acid anhydride-based curing agent, or the like can be cited. The epoxy resin and the curing agent can be used in any combination selected from these epoxy resins and curing agents. Also, as an additive, a dispersant such as a polycarboxylic acid-based dispersant, a silane coupling agent such as a silane coupling agent having an epoxy group, a silane coupling agent having various functional groups such as a methyl group, a phenyl group, a vinyl group, an amino group, an isocyanate group, or the like can be added.

[0081] The magnetic powder is dispersed in the resin. As the magnetic powder, a magnetic metal, a magnetic oxide, or the like can be used. From the viewpoint of the use environment, the magnetic powder is preferably a metal or an oxide having a strong magnetism at normal temperature, for example, a nickel powder, a cobalt powder, an iron powder, an amorphous iron powder, an iron-silicon alloy-based powder, a ferrite (for example, an iron-nickel-based ferrite powder, an iron-zinc-based ferrite powder), or the like. The magnetic powder can be the same composition or a mixture of magnetic powders of different compositions.

[0082] From the viewpoint of further exerting the effects of increasing the high filling of the magnetic powder of the adhesive portion 7 and the characteristics of the coil member, a powder that is easy to control the particle size distribution is preferred, and thus a metal magnetic powder produced by a liquid phase reduction method or an atomization method is preferred.

[0083] The magnetic powder contains first particles having a particle diameter in the range of 0.1 μm to 2.0 μm and second particles having a particle diameter in the range of 3.0 μm to 8.0 μm. In the bonding portion 7, the proportion of the number of the first particles to the total number of particles of the magnetic powder is in the range of 0.11 to 0.80, the proportion of the number of the second particles to the total number of particles of the magnetic powder is in the range of 0.19 to 0.89, the total of the number of the first particles and the number of the second particles to the total number of particles of the magnetic powder is 0.84 or more, and in the cross section of the bonding portion, the proportion of the area of the magnetic powder to the area of the bonding portion 7 (sometimes referred to as the filling rate) is 25.0% or more. Note that the proportion of the number of the first particles to the total number of particles of the magnetic powder is sometimes referred to as the number of first particles / total number of particles, the proportion of the number of the second particles to the total number of particles of the magnetic powder is sometimes referred to as the number of second particles / total number of particles, and the total of the number of the first particles and the number of the second particles to the total number of particles of the magnetic powder is sometimes referred to as (number of first particles + number of second particles) / total number of particles.

[0084] By containing the magnetic powder to satisfy the above conditions, the magnetic resistance of the coil member 1 can be reduced, the impedance value can be increased, and the adhesion can also be ensured. Thus, the increase in the fixing force and the improvement in the product characteristics can be achieved.

[0085] The above-described measurement will be described.

[0086] The particle size distribution of the magnetic powder is obtained by performing SEM observation of the cross section of the bonding portion 7 at 20 visual fields at a magnification of 5000 times and 5 kV, performing measurement of the diameters of the magnetic powder in the visual fields, and collecting the number of the magnetic powder. An example of the image is shown in Figure 3 The obtained data is calculated as a histogram of the number with respect to the particle diameter (circular equivalent diameter). From the obtained particle size distribution, the total number of particles, the number of the first particles, and the number of the second particles are collected, and the values of the number of first particles / total number of particles, the number of second particles / total number of particles, and (number of first particles + number of second particles) / total number of particles are calculated.

[0087] The filling rate is a value calculated by performing distribution observation of the cross section of the bonding portion 7 at a magnification of 5000 times by a scanning electron microscope / energy dispersive X-ray spectroscopy (SEM-EDX) and calculating the proportion of the cross-sectional area of the magnetic powder component by binary processing.

[0088] The particle size distribution can have only one peak or can have multiple peaks.

[0089] The magnetic permeability μ' of the adhesive portion 7 at 1 MHz is, for example, 4.6 or more, and preferably 5.0 or more. By having such a magnetic permeability μ', the magnetic resistance of the coil member 1 can be reduced, and the product characteristics can be improved. The upper limit of the magnetic permeability μ' is not particularly limited, but is, for example, 20.0.

[0090] The filling rate is preferably 35.1% or more. By having such a filling rate, the proportion of the area of the magnetic powder of the adhesive portion increases, and the magnetic resistance can be reduced.

[0091] The filling rate is, for example, 80% or less, and specifically 50% or less. By having such a filling rate, the adhesive portion 7 can be easily formed. For example, when the adhesive portion 7 is provided by coating the adhesive portion before curing as described later, the coating of the composition can be performed well.

[0092] The proportion of the total number of the first particles and the second particles with respect to the total number of the magnetic powder is preferably 0.90 or more. By containing the first particles and the second particles in such a proportion, the adhesion of the core member to the plate member can be ensured, and the magnetic resistance of the coil member can be reduced, and the product characteristics can be improved. The upper limit of the proportion of the total number of the first particles and the second particles with respect to the total number of the magnetic powder is, for example, less than 1.0.

[0093] The proportion of the number of the first particles with respect to the number of the second particles (i.e., the number of the first particles / the number of the second particles) is, for example, in the range of 0.10 to 10.0, and within the above range, it is preferably 0.10 to 5.0. By having the first particles and the second particles in the above proportion, the filling rate can be a good value, the magnetic resistance of the coil member can be reduced, and the improvement of the product characteristics can be facilitated. In addition, when the above proportion is too high, the coatability becomes high, and if the above proportion is too low, the filling rate becomes low, and sometimes the magnetic permeability is affected.

[0094] (Examples)

[0095] Hereinafter, examples of the present disclosure will be described, but the present disclosure is not limited to the description below.

[0096] (Examples 1 to 7, Comparative Examples 8 to 13)

[0097] <Manufacture of Adhesive Portion>

[0098] As the magnetic powder, nickel powder was used, as the polymer material, bisphenol F type epoxy resin was used, as the curing agent, dicyandiamine was used, as the additive, a polybasic acid type dispersant and a silane coupling agent having an epoxy group were used, these materials were mixed to make the dispersion state uniform, and an adhesive was prepared. A cured product of the composition shown in Table 1 was prepared from the prepared adhesive. The cured product corresponds to the adhesive portion. Note that Test Nos. 1 to 7 correspond to Examples 1 to 7, and Test Nos. 8 to 12 correspond to Comparative Examples 8 to 12. The details of the nickel powder used are as follows.

[0099] Test Nos. 1, 3, 5 to 7, and 11: The following two kinds of nickel powder were used.

[0100] Nickel powder having a peak of the particle size distribution in the range of 0.1 μm to 2.0 μm and nickel powder having a peak of the particle size distribution in the range of 3.0 μm to 8.0 μm

[0101] Test No. 2: The following two kinds of nickel powder were used.

[0102] Nickel powder having a peak of the particle size distribution in the range of more than 2.0 μm and less than 3.0 μm and nickel powder having a peak of the particle size distribution in the range of 3.0 μm to 8.0 μm

[0103] Test Nos. 4 and 9: The following one kind of nickel powder was used.

[0104] Nickel powder having a peak of the particle size distribution in the range of 3.0 μm to 8.0 μm

[0105] Test No. 8: The following one kind of nickel powder was used.

[0106] Nickel powder having a peak of the particle size distribution in the range of 0.1 μm to 2.0 μm

[0107] Test No. 10: The following two kinds of nickel powder were used.

[0108] Nickel powder having a peak of the particle size distribution in the range of 0.1 μm to 2.0 μm and nickel powder having a peak of the particle size distribution in the range of more than 9.0 μm and 11.0 μm or less

[0109]

[0110] The evaluation method described in Table 1 is shown below.

[0111] <Coatability>

[0112] The coatability of the adhesive portion before curing was evaluated by printing the adhesive portion before curing on a plate member using a screen plate having an opening portion of a flange area of a core material. The evaluation criteria were as follows.

[0113] O: state without printing bleeding and blurring

[0114] X: at least one of print bleeding and blur exists

[0115] <Permeability>

[0116] The permeability was measured at 1 MHz using an impedance analyzer after the adhesive portion before curing was annularly cured.

[0117] <Adhesiveness>

[0118] Two alumina substrates were prepared. The adhesive portion before curing was applied to one of the alumina substrates, and the other alumina substrate was disposed thereon to be pressed, and then the adhesive portion was cured by heating at 150°C for 1 hour. Thereafter, the portion protruding from the alumina substrate at the time of pressing was removed, thereby forming an adhesive portion of 5 mm x 5 mm. A tensile strength test was performed using an Autograph manufactured by Shimadzu Corporation. The evaluation criteria were as follows.

[0119] O: the breaking strength of the adhesive portion is 8 MPa or more

[0120] X: the breaking strength of the adhesive portion is less than 8 MPa

[0121] <Properties of Products>

[0122] O: the Lc increase rate is 30% or more with respect to Test No. 12 (Lc: 110) not using magnetic powder

[0123] O: the Lc increase rate is less than 15% or more than 30% with respect to Test No. 12 (Lc: 110) not using magnetic powder

[0124] X: the Lc increase rate is less than 15% with respect to Test No. 12 (Lc: 110) using magnetic powder

[0125] <Lc Value>

[0126] The Lc value was determined as follows. The Lc value at a measurement frequency of 100 kHz was measured (n = 30) using an impedance analyzer 4294A (Keysight Technologies, Inc.), and the average value thereof was taken as the Lc value.

[0127] As shown in Examples 1 to 7, by satisfying the number of particles of the first particles / total number of particles is 0.11 to 0.80, the number of particles of the second particles / total number of particles is 0.19 to 0.89, and (the number of particles of the first particles + the number of particles of the second particles) / total number of particles is 0.84 or more, and the filling rate is 25% or more, the adhesiveness is good, and the inductance value of the coil member is high.

[0128] The number of particles of the first particles in Comparative Example 8 is large, and as a result, the viscosity of the adhesive portion before curing becomes too high, and the coatability is poor. In addition, in Comparative Example 8, although the value of (the number of particles of the first particles + the number of particles of the second particles) / the total number of particles is as high as 0.94, the number of particles of the first particles is very large, and therefore the value of the filling rate cannot satisfy 25.0% or more, and as a result, the impedance value is not improved. In addition, the value of the magnetic permeability is also low.

[0129] In Comparative Example 9, the number of particles of the second particles is large, and although the value of (the number of particles of the first particles + the number of particles of the second particles) / the total number of particles is as high as 0.99, the value of the filling rate cannot satisfy 25.0% or more, and as a result, the impedance value is not improved. In addition, the value of the magnetic permeability is also low.

[0130] In Comparative Example 10, although the value of the filling rate is good, the number of particles of the second particles / the total number of particles is small, and the value of (the number of particles of the first particles + the number of particles of the second particles) / the total number of particles is also low. As a result, the impedance value is not improved, and in addition, the evaluation of the adhesiveness is also X. In addition, the value of the magnetic permeability is also low.

[0131] In Comparative Example 11, the number of particles of the first particles / the total number of particles is 0.11 to 0.80, and the number of particles of the second particles / the total number of particles is 0.19 to 0.89, but the value of (the number of particles of the first particles + the number of particles of the second particles) / the total number of particles is low, and the value of the filling rate is also low. As a result, the impedance value is not improved. In addition, the value of the magnetic permeability is also low.

[0132] In Comparative Example 12, the magnetic powder is not contained, and the magnetic resistance cannot be reduced, and the characteristics of the product are not improved. In addition, the value of the magnetic permeability is of course low.

[0133] That is, as shown in Comparative Examples 8 to 12, it is understood that only when the number of particles of the first particles / the total number of particles, the number of particles of the second particles / the total number of particles, (the number of particles of the first particles + the number of particles of the second particles) / the total number of particles, and the filling rate all have appropriate values, good adhesiveness can be obtained, and the magnetic resistance can be reduced, and the impedance value can be improved.

[0134] (Second Embodiment)

[0135] Figure 4 is a plan view of the coil member 1A of the second embodiment, and is an explanatory view of the first flange portion 4a of the coil member 1A viewed from the T direction. Figure 5 is a plan view of the coil member 1A of the second embodiment, and is an explanatory view of the first flange portion 4a of the coil member 1A viewed from the T direction. Figure 4 is an X-X sectional view of the coil member 1A of the second embodiment, in other words, a sectional view including the T direction and the L direction. It should be noted that Figure 4 in the coil member 1A of the second embodiment, the plate member 6 and the wire 15 are omitted, Figure 5 in the coil member 1A of the second embodiment, the wire 15 is omitted.

[0136] The shape of the upper surface of the flange portion of the core material in coil component 1A differs from that in coil component 1 of the first embodiment. This difference will be explained below. Other configurations are the same as in the first embodiment, and descriptions are sometimes omitted.

[0137] like Figure 4 and Figure 5 As shown, the first flange portion 4a of the core material 2a of the coil component 1A has a flat portion 43a2 and a protrusion 43a1 protruding from the flat portion 43a2 toward the plate component 6 on its upper surface 43a. The gap between the first flange portion 4a and the plate component 6, and between the protrusion 43a1 and the second main surface 62 of the plate component 6, is narrower than the gap between the flat portion 43a2 and the second main surface 62 of the plate component 6. That is, the gap between the first flange portion 4a and the plate component 6 includes a first portion Z1 with a narrow gap and a second portion Z2 with a wider gap than the first portion Z1. The first portion Z1 corresponds to the portion between the protrusion 43a1 and the second main surface 62 of the plate component 6, and the second portion Z2 corresponds to the portion between the flat portion 43a2 and the second main surface 62 of the plate component 6.

[0138] In other words, the adhesive portion 7a has a thin first portion 7a1 and a thicker second portion 7a2 than the first portion 7a1. The first portion 7a1 of the adhesive portion 7a exists in the first portion Z1, and the second portion 7a2 of the adhesive portion 7a exists in the second portion Z2.

[0139] By using this embodiment, by providing the first portion Z1, the distance between the first flange portion 4a and the plate component 6 is reduced, thereby reducing the magnetic resistance of the coil component 1A. By providing the second portion Z2, the distance between the first flange portion 4a and the plate component 6 is increased, thereby increasing the amount of the adhesive portion 7a and further improving the adhesion between the core material 2a and the plate component 6.

[0140] Preferably, the spacing of the first part Z1 is in the range of 1 μm to 10 μm, and the spacing of the second part Z27a2 is in the range of 5 μm to 20 μm. By keeping the spacing of the first part Z1 and the second part Z2 within the above range, the magnetic reluctance of the coil component 1A can be reduced, and the adhesion between the core material 2a and the plate component 6 can be further improved.

[0141] Preferably, the first particle is present in more of the first part Z1 than the second part Z2. This results in a moderate presence of magnetic powder in the first part.

[0142] Preferably, the second particle is present in more form in the second part Z2 than in the first part Z1. This results in a moderate presence of magnetic powder in the second part.

[0143] For example, the aforementioned non-uniformity between the first and second particles can be controlled and configured as follows: During the manufacturing stage, a paste containing the first and second particles is applied to the upper surface 43a of the first flange portion 4a, with the second portion Z2 tilted relative to the first portion Z1 so that its vertical direction is downward. Because the second particle is heavier than the first particle, it is positioned downward relative to the first particle due to gravity, in other words, flowing into both sides of the second portion Z. This results in a greater presence of the second particle in the second portion Z2 and a greater presence of the first particle in the first portion Z1.

[0144] Preferably, the area S1 of the protrusion 43a1 is set to be the ratio of the total area S1 of the protrusion 43a1 and the area S2 of the flat portion 43a2 of the first part Z1, that is, S1 / (S1+S2) is in the range of 0.1 to 0.9. This better reduces the magnetic reluctance of the coil component, improves the product characteristics, and further enhances the adhesion between the core material 2a and the board component.

[0145] Area S1 is equivalent to the area occupied by the first part Z1 when viewed from the T direction. Area S2 is equivalent to the area occupied by the second part Z2 when viewed from the T direction.

[0146] The second flange of the coil component 1A has the same structure as the first flange 4a.

[0147] (Third Implementation)

[0148] Figure 6 This is a cross-sectional view showing the coil component 1B according to the third embodiment. It should be noted that... Figure 6 The cable is omitted in the middle.

[0149] The structure of coil component 1B differs from that of the plate component of coil component 1 in the first embodiment. This difference will be explained below. Other configurations are the same as in the first embodiment, and some details are omitted.

[0150] like Figure 6 As shown, the second main surface 62b of the plate member 6b of the coil member 1B has a flat portion 62b2 and a protrusion 62b1 protruding from the flat portion 62b2 toward the first flange portion 4. The gap between the plate member 6b and the first flange portion 4, and between the protrusion 62b1 and the upper surface 43 of the first flange portion 4, is narrower than the gap between the flat portion 62b2 and the first flange portion 4. That is, in the gap between the plate member 6b and the first flange portion 4, there exists a first portion Z1 with a narrow gap and a second portion Z2 with a gap wider than the first portion Z1. The first portion Z1 corresponds to the portion between the protrusion 62b1 and the upper surface 43 of the first flange portion 4, and the second portion Z2 corresponds to the portion between the flat portion 62b2 and the upper surface 43 of the first flange portion 4.

[0151] In other words, the bonding portion 7b has a first portion 7b1 having a small thickness and a second portion 7b2 having a thickness larger than that of the first portion 7b1. The first portion 7b1 of the bonding portion 7b is present in the above-described first portion Z1, and the first portion 7b1 of the bonding portion 7b is present in the above-described first portion Z1.

[0152] With the present embodiment, by providing the first portion Z1, the distance between the first flange portion 4 and the plate member 6b becomes small, and the magnetic resistance of the coil member 1B can be reduced. By providing the second portion Z2, the distance between the first flange portion 4 and the plate member 6b becomes large, and the amount of the bonding portion 7b can be increased, and the adhesion of the core material 2 to the plate member 6b can be further improved.

[0153] Further, in the coil member 1B, in a cross section of a plane including the central axis direction of the winding core portion and the direction in which the first flange portion 4 opposes the plate member 6b, the first portion Z1 is present on the winding core portion 3 side with respect to the second portion Z2, that is, on the inner surface 41 side of the first flange portion 4. By having such a configuration, the magnetic path length of the winding core portion 3, the flange portion, and the plate member 6b becomes short, and as a result, the inductance value can be further increased. The direction in which the first flange portion 4 opposes the plate member 6b is the same as the direction in which the second flange portion opposes the plate member 6b.

[0154] The plate member 6b of the coil member 1B has the same configuration at the position opposing the first flange portion 4 as at the position opposing the second flange portion.

[0155] (4th Embodiment)

[0156] Figure 7 is a cross-sectional view showing the coil member 1C of the 4th embodiment. Note that, Figure 7 the wire 15 is omitted.

[0157] The configuration of the core material and the plate member of the coil member 1C is different from that of the coil member 1 of the 1st embodiment. Hereinafter, the points of difference will be described. The other configurations are the same as those of the 1st embodiment, and the description thereof will be omitted at times.

[0158] As shown in Figure 7 the first flange portion 4c of the core material 2c of the coil member 1C has a flat portion 43c2 and a protruding portion 43c1 protruding from the flat portion 43c2 toward the plate member 6c direction on the upper surface 43c. The plate member 6c has a flat portion 62c2 and a recessed portion 62c1 recessed from the flat portion 62c2 toward the opposite direction of the first flange portion 4c on the second main surface 62c.

[0159] The interval between the convex portion 43cl of the upper surface 43c of the first flange portion 4c and the concave portion 62cl of the second main surface 62c of the plate member 6c is narrower than the interval between the flat portion 43c2 of the first flange portion 4c and the flat portion 62c2 of the second main surface 62c of the plate member 6c. That is, the interval between the first flange portion 4c and the plate member 6c has a first portion Zl having a narrow interval and a second portion Z2 having a wider interval than the first portion Zl. The first portion Zl corresponds to the portion between the convex portion 43cl of the upper surface 43c and the concave portion 62cl of the second main surface 62c, and the second portion Z2 corresponds to the portion between the flat portion 43c2 of the upper surface 43c and the flat portion 62c2 of the second main surface 62c.

[0160] In other words, the bonding portion 7c has a first portion 7cl having a small thickness and a second portion 7c2 having a larger thickness than the first portion 7cl. The first portion 7cl of the bonding portion 7c is present in the above-described first portion Zl, and the second portion 7c2 of the bonding portion 7c is present in the above-described second portion Z2.

[0161] With the present embodiment, by providing the first portion Zl, the distance between the first flange portion 4c and the plate member 6c becomes narrow, and the magnetic resistance of the coil member 1C can be reduced. By providing the second portion Z2, the distance between the first flange portion 4c and the plate member 6c becomes large, and the amount of the bonding portion 7c can be increased, and the adhesion between the core material 2c and the plate member 6c can be further improved.

[0162] The second flange portion of the coil member 1C has the same structure as the first flange portion 4c. The plate member 6c has the same structure as the position opposite to the first flange portion 4c at a position opposite to the second flange portion.

[0163] (5th Embodiment)

[0164] Figure 8 is a cross-sectional view of the coil member 1D of the 5th embodiment. Note that, Figure 8 The wire 15 is omitted in the present embodiment.

[0165] The structure of the upper surface of the flange portion of the core material of the coil member 1D is different from that of the coil member 1A of the 2nd embodiment. Hereinafter, the different points will be described. The other configurations are the same as those of the 2nd embodiment, and the description thereof will be omitted at times.

[0166] In the present embodiment, the upper surface 43d of the first flange portion 4d of the core material 2d of the coil member 1D has a protruding convex curved surface in the direction of the plate member 6c, unlike the 2nd embodiment in which the upper surface 43a of the core material 2a has the flat portion 43a2 of the convex portion 43al.

[0167] As Figure 8As shown, the upper surface 43d of the first flange portion 4d is curved in a cross section including the T direction and the L direction. In the upper surface 43d of the first flange portion 4d, the central position in the L direction is the closest to the plate member 6 in the curvature. In the inner surface 41 and the outer surface 42 of the first flange portion 4d, the upper surface 43d is the farthest from the plate member 6, and the distance from the plate member 6 is the same on the inner surface 41 side and the outer surface 42 side.

[0168] Note that the curvature can be a circular arc or an elliptical arc. Also, the vertex of the curvature can not be located at the center of the first flange portion 4d. The distance of the plate member 6 from the inner surface 41 side and the distance of the plate member 6 from the outer surface 42 side can be different.

[0169] In the present embodiment, the first portion Z1 is a region including the minimum distance, centered on the vertex of the curvature of the upper surface 43d of the first flange portion 4d, and occupying half the width of the first flange portion 4d, and the second portion Z2 is a portion other than the first portion, and is a portion including the maximum gap.

[0170] In other words, the bonding portion 7d has a first portion 7d1 that is thin and a second portion 7d2 that is thicker than the first portion 7d1. The first portion 7d1 of the bonding portion 7d is present in the above-described first portion Z1, and the second portion 7d2 of the bonding portion 7d is present in the above-described second portion Z2.

[0171] With the present embodiment, by providing the first portion Z1, the distance of the first flange portion 4d from the plate member 6 becomes closer, and the magnetic resistance of the coil member 1D can be reduced. By providing the second portion Z2, the distance of the first flange portion 4d from the plate member 6 becomes larger, and the amount of the bonding portion 7d can be increased, and the adhesion of the core material 2d to the plate member 6 can be further improved.

[0172] The second flange portion of the coil member 1D has the same structure as the first flange portion 4d.

[0173] Note that the present disclosure is not limited to the above-described first to fifth embodiments, and design changes can be made without departing from the gist of the present disclosure.

[0174] Each material is not limited to the above-described examples, and known materials can be used.

[0175] In the first to fifth embodiments, the bonding portion is provided between the winding core portion of the core material and the plate member, but in other modes, the bonding portion can be provided between the winding core portion of the core material and the plate member.

[0176] In the second to fifth embodiments, the upper surface of the protrusion and the bottom surface of the recess are flat surfaces, but can also be curved shapes. The cross-sectional shape of the protrusion can also be circular.

[0177] From the first embodiment to the third embodiment, the upper surface of the first flange portion and the upper surface of the second flange portion of the core material have the same shape, but each can have a different shape.

[0178] From the first embodiment to the fifth embodiment, the surface of the plate member opposite the first flange portion and the surface of the plate member opposite the second flange portion can have the same shape, but each can have a different shape.

[0179] From the first embodiment to the fifth embodiment, the wire can be one, or two or more.

[0180] From the first embodiment to the fifth embodiment, one terminal electrode can be provided in each flange portion, but a plurality of terminal electrodes can also be provided in each flange portion.

Claims

1. A coil component comprising: a core material having a core portion, a first flange portion provided at a first end portion of the core portion, and a second flange portion provided at a second end portion of the core portion, a wire wound around the core portion of the core material, a plate member provided so as to straddle the first flange portion and the second flange portion, and an adhesive portion provided between the first flange portion and the plate member and bonding the first flange portion and the plate member, and an adhesive portion provided between the second flange portion and the plate member and bonding the second flange portion and the plate member; the adhesive portion containing a resin and a magnetic powder, the magnetic powder containing first particles having a particle diameter in a range of 0.1 μm to 2.0 μm and second particles having a particle diameter in a range of 3.0 μm to 8.0 μm, a proportion of the number of the first particles with respect to the total number of particles of the magnetic powder being in a range of 0.11 to 0.80, a proportion of the number of the second particles with respect to the total number of particles of the magnetic powder being in a range of 0.19 to 0.89, a total of the number of the first particles and the number of the second particles with respect to the total number of particles of the magnetic powder being 0.84 or more, and a proportion of the area of the magnetic powder with respect to the area of the adhesive portion in a cross section of the adhesive portion being 25.0% or more. The magnetic permeability μ' of the adhesive portion at 1 MHz is 4.6 or more. The proportion of the area of the magnetic powder is 35.1% or more. The proportion of the total of the number of the first particles and the number of the second particles is 0.90 or more. At least one of a gap between the first flange portion and the plate member and a gap between the second flange portion and the plate member has a first portion having a narrow gap and a second portion having a wider gap than the first portion.

6. The coil component according to claim 5, wherein The gap of the first portion is in a range of 1 μm to 10 μm. The gap of the second portion is in a range of 5 μm to 20 μm. The first particles are present more in the first portion with respect to the second portion. The second particles are present more in the second portion with respect to the first portion. In a cross section of a plane including a central axis direction of the core portion and a direction in which the first flange portion and the plate member face each other, the first portion is present closer to the core portion side than the second portion.

2. The coil component according to claim 1, wherein ​ 3. The coil component according to claim 1 or 2, wherein ​ 4. The coil component according to Claim 1 or 2, wherein ​ 5. The coil component according to claim 1 or 2, wherein ​ ​ ​ ​ 7. The coil component according to claim 5, wherein ​ 8. The coil component according to claim 5, wherein ​ 9. The coil component according to Claim 5, wherein ​

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