JP5110624B2 - Wire ring parts - Google Patents

Description

  The present invention relates to a wire ring component such as a choke coil for an electronic device and a transformer suitable for use in a region of several hundred kHz or less and a maximum applied magnetic field H = 3.98 kA / m or more.

  Application destinations of these wire ring components include, for example, wire ring components for increasing voltage control and decreasing voltage control used for solar power generation, wind power generation, and the like. The implementation of concrete measures to combat global warming has become an urgent task, and competition for clean energy such as fuel cell vehicles has intensified. Furthermore, in the private sector such as home and business, the government and local governments have strengthened subsidies, and have begun to establish a decentralized power generation system that does not emit greenhouse gases such as solar power generation, small wind power generation, and fuel cell power generation. Yes.

  As elemental technologies common to these fuel cell vehicles and distributed power supply facilities, a DC voltage step-up / down circuit (DD converter) and a DC-AC converter circuit (inverter) are inserted in the power supply system. It is necessary not to consume power unnecessarily in this circuit.

  In the case of power conversion from direct current to alternating current by a DD converter or inverter circuit, the inductor for the filter to prevent the outflow of the harmonic current to the output system, and the converter for raising and lowering the voltage instantaneously Inductors that can be stored as magnetic energy are required, and in all cases, optimal inductors that are small, light, energy-saving, resource-saving, and quiet are required.

  The conventional magnetic core has adjusted the direct current superposition characteristics by a macro gap. For this reason, leakage magnetic flux was generated and audible noise was easily generated. Moreover, the magnetic core of a closed magnetic circuit has been manufactured by press molding or injection molding in order to obtain a high magnetic permeability with a low magnetic field. However, investment in large-scale and expensive equipment and molds is necessary for their industrialization.

  When the drive frequency or standby mode frequency of the coil component ranges from several kHz to several tens of kHz in the audible region, vibration due to the mutual attractive force occurs between the coil wires and between the coil and the magnetic core. For this reason, there is a problem of generating audible noise and beat.

  As is clear from the description in Patent Document 1, the frequency range targeted by the coil component described in Patent Document 1 is a so-called “high frequency”, which is a frequency region far exceeding the audible frequency. In fact, Patent Document 1 has a description of “several hundred kHz to MHz”, and the term “high frequency” is frequently used as a keyword.

  Even if the air gap part vibrates at a very high frequency of several hundred kHz to MHz, it will only generate sound that cannot be heard by the human ear, and it is possible that it will result in audible noise and beating as described above. Absent.

  Therefore, it is appropriate to consider a solution for audible noise and beat caused by driving in the audible frequency band, apart from the technique described in Patent Document 1. In addition, the coil component targeted in Patent Document 1 is exemplified. As is clear from the size and the like, it is a coil component for a low power system. Therefore, as a matter of course, a withstand voltage performance of several hundred volts or more or an unnecessary pulse current performance of several hundred amperes or more (resistance to unwanted current noise such as surge current) cannot be expected.

  As described above, it is appropriate to consider that it is inappropriate to use the coil component described in Patent Document 1 for high power / low frequency applications.

  In view of the above, the present invention provides a wire ring component that has high withstand voltage performance and high anti-unnecessary pulse current performance and can suppress audible noise and beat even when driven at a frequency that is in the audible frequency range. The purpose is to provide.

JP 2001-185421 A

  A need that cannot be dealt with by the prior art is a winding-integrated magnetic core without a macro gap. Even if the same soft magnetic material is used, the loss can be reduced by reducing the size of the winding as a single unit. At this time, the applied magnetic field H = N · I / le due to the magnetomotive force of the winding can be determined by the number of turns N, the maximum current I, and the effective magnetic path length le. Among them, the effective magnetic path length le can be reduced to reduce the size.

  However, since the applied magnetic field H becomes larger, it is necessary to obtain a higher magnetic permeability in the maximum applied magnetic field. In other words, even with the same material, up to which magnetic field is used, the effective cross-sectional area of the magnetic circuit differs depending on the external dimensions of the product. For this reason, the applied magnetic field and the magnetic permeability required of the material change.

  This time, the magnetic core and wire ring parts have been constructed at a lower price with a micro dispersion gap rather than a macro gap. In response to market needs, we have invented low-loss and quiet products centered on miniaturization.

  As electronic devices are becoming smaller and smaller, high-efficiency magnetic materials are required, and as choke coils used at high frequencies, ferrite cores, silicon steel plates / amorphous ribbons, dust cores, etc. are used. .

  Selection of a suitable magnetic core can be classified according to the driving frequency of the electronic device and the maximum applied magnetic field of the inductor.

  When H is less than 3.98 kA / m, ferrite having a gap is mainly used.

  Up to H = 7.96 kA / m, silicon steel plates with gaps are mainly used.

  Up to H = 15.92 kA / m, a dust core or a silicon steel plate with a gap is used.

  Furthermore, at 15.92 kA / m or more (H = 31.84 kA / m level), it is difficult to select a suitable magnetic core.

  The magnetic permeability of each soft magnetic material is determined by the winding, the maximum current, and the magnetic path length, and particularly depends on the applied magnetic field.

Area A: H = less than 3.98 kA / m The saturation magnetic flux density of the ferrite core is small. Moreover, the following problems can be pointed out in the case of a ferrite magnetic core provided with a gap. First, magnetic flux leaks to the outside of the magnetic core, generating eddy currents on the copper wire surface.

  When the litz wire is not used, the eddy current loss in the winding portion is large and the temperature rise of the inductor cannot be used remarkably. Next, as a countermeasure against eddy current loss in the winding portion due to leakage magnetic flux, a so-called litz wire in which a large number of thin copper wires are bundled is used. However, the litz wire has a lower space factor than the single wire, increases the direct current resistance, and requires a larger magnetic core than the single wire in order to obtain the same inductance value. In addition, the litz wire is more expensive than the single wire.

  Ferrite has an excellent feature that its iron loss is remarkably low compared to silicon steel plates, amorphous ribbons and the like. However, when the gap is provided as described above, the advantage cannot be fully utilized due to the eddy current loss in the winding portion due to the leakage magnetic flux. Furthermore, since ferrite is made of a metal oxide, it has the disadvantages that the saturation magnetic flux density is essentially lower than that of a metal-based soft magnetic material, the magnetic flux is easily saturated, and the temperature dependence of loss is large. For this reason, the ferrite magnetic core has to prevent magnetic saturation by increasing the cross-sectional area of the magnetic core as compared with a magnetic core made of a metallic soft magnetic material, and it is difficult to reduce the size of the magnetic core.

Region B: Up to H = less than 7.96 kA / m For example, a 100-micron ribbon such as silicon steel can exhibit an advantage of particularly high μ in this range. When comparing with the same composition, the reason why the magnetic permeability is higher than that of the powdered magnetic core is that the demagnetizing factor is lowered by using a thin ribbon and the spin magnetization rotation mode having a low coercive force is used. However, due to the increase in eddy current loss due to the ribbon thickness, it can only be applied up to about 40 kHz. Although thinner ribbons are being developed, the manufacturing costs are very high. There is also a problem of processing accuracy of the macro gap portion.

Area D: H = 1.92 kA / m or less For example, Sendust green compact is used. A dust core produced by molding soft magnetic powder has a higher saturation magnetic flux density than ferrite, which is advantageous for downsizing, but is superior to ferrite in terms of permeability and iron loss. However, it is difficult to reduce the size in that respect.

  For example, a ferrite core without a macro gap has an inductance L value that suddenly decreases with a DC superimposed current that becomes a magnetic field of about H = 1 kA / m, whereas a dust core without a macro gap has a DC superimposed current. It decreases gradually against. This is presumably because there is a distribution in the micro-dispersion gap present in the dust core. In order to ensure the permeability up to higher magnetic fields, it seems necessary to adapt the micro gap. When the microgap is increased, the magnetic permeability of the magnetic core tends to decrease.

  The core loss of a dust core usually consists of hysteresis loss and eddy current loss, but the eddy current loss increases in proportion to the square of the frequency and the square of the size through which the eddy current flows. The generation of eddy current is suppressed by covering the electrically insulating resin or the like. On the other hand, in order to increase the molding density of the dust core, it is usually necessary to apply a molding pressure of 500 MPa or more. Therefore, the hysteresis loss increases as the magnetic material increases in strain and the permeability deteriorates. It was something that would end up. In order to avoid this, a post-molding heat treatment is performed as necessary to release the strain. However, when high-temperature heat treatment is required, an insulating binder is necessary to insulate the magnetic powder and maintain the binding between the powders.

Area E: H = 31.84 kA / m level (15.92 kA / m or more)
Even in a dust core, in order to make the distribution of the magnetic flux density in a plurality of macro gaps and magnetic cores more uniform, it is an area that needs to be partially magnetized in the direction of difficult magnetization. It caused a significant increase in winding eddy current loss. In this region, it is difficult to select a suitable magnetic core.

  As described above, the present invention is particularly suitable for use in large currents to provide choke coils, transformers, and other wire ring parts used in electronic equipment up to a frequency of several hundreds of kHz with good superposition characteristics at large currents. An object of the present invention is to provide a composite magnetic material suitable for a magnetic core for a wire ring component and capable of ensuring a high magnetic permeability in a region of a maximum applied magnetic field H = 3.98 kA / m or more.

  The present inventors have found that it is preferable to use a magnetic core having a microgap made of a mixture of magnetic powder and resin as a wire ring part having a high current direct current superposition characteristic. In particular, since it is considered effective to increase the filling rate of the magnetic material and to make the microgap uniform, the present invention was obtained as a result of studying the composition of the admixture for that purpose. is there.

That is, the present invention provides a wire using a magnetic core obtained by solidifying or curing an admixture of a first magnetic powder, a second magnetic powder having a smaller diameter or a nonmagnetic powder, and a resin. The magnetic core has a relative permeability μdc in a magnetic field of 7.96 kA / m of 10 or more, and an effective demagnetizing factor N of the first magnetic powder is 0.4. The total filling rate of the first magnetic powder and the smaller second magnetic powder or non-magnetic powder is 50 vol% or more, and the average particle size of the first magnetic powder The average particle diameter φ2 of the smaller second magnetic powder or nonmagnetic powder with respect to the diameter φ1 is φ2 = <φ1 / 15, and the volume of the smaller second magnetic powder or nonmagnetic powder. The fraction is 40 vol% or less of the whole and further contains nano-sized anhydrous silica. It is a characteristic wire ring part.

Further, the present invention provides the wire ring component, wherein the magnetic core has a relative permeability μdc in a magnetic field of 3 1.84 kA / m of 2 or more.

Further, the present invention, the magnetic core is Senwa component, wherein the relative permeability μdc in the magnetic field of 7 9.6kA / m is 2 or more.

  Further, the present invention is a wire ring component characterized in that at least a part of a winding inclusion insulator obtained by surrounding with an insulating resin so as to exclude an end portion of the winding is embedded in the magnetic core. .

  Further, the present invention is a wire ring component characterized in that all of the winding inclusion insulator obtained by surrounding with an insulating resin so as to exclude the end of the winding is embedded in the magnetic core.

Further, the present invention is a Senwa component, wherein the second magnetic powder or nonmagnetic powder smaller diameter than previous SL is substantially spherical powder.

In addition, the present invention provides a wire ring component in which half or less of the second magnetic powder or non-magnetic powder having a smaller diameter is a powder having a particle diameter of φ1 / 50 or less.

Further, the present invention is characterized in that the winding inclusion insulator is obtained by uniformly impregnating with a mixture of insulating nonmagnetic powder containing at least the nano-sized anhydrous silica and resin, and solidifying or curing. It is a wire ring part.

  The present invention also provides the wire ring component, wherein the magnetic powder is made of soft magnetic powder.

  The present invention also provides a wire ring component, wherein the magnetic powder includes at least a soft magnetic powder.

  In addition, the present invention provides the wire ring component, wherein the soft magnetic powder includes at least an Fe—Si based powder.

  Further, the present invention provides the wire ring component, wherein an average Si content in the Fe—Si powder is 11.0% by weight or less (not including 0% by weight).

  Moreover, this invention is a wire ring component characterized by the said soft-magnetic powder containing an Fe-Si-Al type powder at least.

  In the present invention, the average Si content in the Fe—Si—Al-based powder is 11.0 wt% or less (excluding 0 wt%), and the average Al content is 7.0 wt% or less (0 (Not including% by weight).

  Moreover, this invention is a wire ring component characterized by the said soft-magnetic powder containing an Fe-Ni type powder at least.

  The present invention also provides the wire ring component, wherein an average Ni content in the Fe—Ni-based powder is 30.0 wt% or more and 85.0 wt% or less.

  In addition, the present invention provides the wire ring component, wherein the soft magnetic powder includes at least an amorphous powder.

  In addition, the present invention provides the wire ring component, wherein the soft magnetic powder contains at least carbonyl iron powder.

  In addition, the present invention provides the wire ring component, wherein the second magnetic powder or nonmagnetic powder having a smaller diameter includes at least a substantially spherical powder.

In addition, the present invention provides a wire ring component in which a specific permeability magnetic core member is embedded in the magnetic core, and the specific permeability magnetic core member includes : A wire ring component having a relative permeability μdc in a magnetic field of 96 kA / m of 1 or more.

Further, the present invention is a wire ring component in which a specific permeability magnetic core member is embedded in the magnetic core, and the specific permeability magnetic core member is 3 . A wire ring component having a relative permeability μdc in a magnetic field of 98 kA / m of 1 or more.

  In addition, the present invention provides a wire ring component in which a specific permeability magnetic core member having a relative permeability μdc of 1 is embedded in a part of the magnetic core.

  The present invention also provides a wire ring component in which a magnetic material processed component is embedded in a part of the magnetic core.

  In addition, the present invention is the wire ring component further including a holding case, wherein at least a part of the mixture is solidified or hardened in the case.

  In the wire ring component, since the winding is surrounded at least by an insulator, the winding is excellent in withstand voltage characteristics and unnecessary pulse current performance, and includes at least a magnetic powder. It is embedded in the magnetic core made of a mixture of resin and resin, and the movement of the winding is fixed. For this reason, even when driven in an audible frequency band, the amplitude of vibration that causes audible noise and beat is smaller.

  Each magnetic field H0 = 5 A / m (initial permeability), H1 = 15.92 kA / m, using a magnetic core obtained by curing a mixture of the first magnetic powder, the second magnetic powder having a smaller diameter, and a resin. The values of relative permeability μ (H0) = 43.4, μ (H1) = 22.4, and μ (H2) = 18.9 at H2 = 31.84 kA / m were obtained.

  Further, a magnetic core obtained by curing an admixture of magnetic powder, smaller-diameter non-magnetic powder and resin, and each magnetic field H0 = 5 A / m (initial permeability), H1 = 15.92 kA / m, H2 = 31. .84 kA / m, H3 = 79.6 kA / m relative permeability μ (H0) = 12.7, μ (H1) = 12.1, μ (H2) = 11.1, μ (H3) = 7 A value of .6 was obtained.

  Further, a magnetic core obtained by curing an admixture imparted with thixotropic properties by adding nano silica, and each magnetic field H0 = 5 A / m (initial permeability), H1 = 15.92 kA / m, H2 = 31.84 kA / M, H3 = 79.6 kA / m relative permeability μ (H0) = 13.7, μ (H1) = 13.2, μ (H2) = 12.0, μ (H3) = 9.0 The value of was obtained. Also, by adding thixotropic properties, there is no difference in density between the upper part and the lower part due to sedimentation, and the rearrangement of primary particles, secondary and tertiary powders during vibration casting, high filling and uniform dispersion are possible. Became.

Conventionally, a magnetic core having a closed magnetic path has been manufactured by press molding or injection molding in order to obtain a high magnetic permeability with a low magnetic field. However, for industrialization, investment in large-scale and expensive equipment and molds is required. In order to avoid this, we have shown an example in which casting is performed directly using a composite magnetic material having fluidity under normal pressure or reduced pressure. In particular, magnetic particles and a group of other small particles are mixed in a resin, made into a slurry, cast under reduced pressure, and magnetically saturated at the core of a conventional closed magnetic circuit due to high filling with suitable components. Magnetic field,
H1 = 15.92 kA / m
H2 = 31.84 kA / m
H3 = 79.6 kA / m
Higher magnetic permeability could be obtained.

  The magnetic core according to the embodiment of the present invention is made of an admixture of resin and powder containing a magnetic material. Specifically, the magnetic core made of an admixture is a cast product obtained by casting the admixture. Here, when the size of the wire ring part is large, it is necessary to consider environmental considerations and energy saving in the manufacturing process during solidification or curing, especially considering the case where the coil part has a certain height or more, add a solvent. It is preferable to use a resin material from which an admixture that can be cast without any problem is obtained.

  By casting, so as to embed all or part of the coil-included insulator obtained by surrounding with the insulating resin so as to remove the end of the coil by this mixture, by forming a magnetic core Wire ring parts are manufactured.

  The magnetic powder constituting the admixture is preferably a soft magnetic powder, specifically, an Fe-based soft magnetic magnetic powder. More specifically, the soft magnetic powder is a powder selected from the group consisting of Fe-Si powder, Fe-Si-Al powder, Fe-Ni powder, and Fe amorphous powder. Here, the average Si content in the Fe—Si based powder is preferably 0.0 wt% or more and 11.0 wt% or less. Further, the average Si content in the Fe—Si—Al-based powder is preferably 0.0 wt% or more and 11.0 wt% or less, and the average Al content is preferably 0.0 wt% or more and 7.0 wt%. It is as follows. Further, the average Ni content in the Fe—Ni-based powder is preferably 30.0 wt% or more and 85.0 wt% or less.

  In particular, a substantially spherical powder is used as the magnetic powder according to the present embodiment. When the substantially spherical magnetic powder is used as described above, the filling rate of the magnetic powder in the mixture can be improved. Such a substantially spherical magnetic substance powder is obtained, for example, by a gas atomizing method. According to the gas atomization method, the particle size and shape of the magnetic powder have a certain distribution, but as a guide, the most standard particle size (average particle size D50) of the magnetic powder is 500 μm or less. Desirably, when it exceeds this, sufficient yield, characteristics and performance cannot be obtained.

  According to the gas atomization method, a non-spherical powder can be intentionally formed in addition to the substantially spherical powder as described above. Moreover, according to the water atomization method, an amorphous powder can also be obtained. In the present invention, non-spherical powder, amorphous powder, and other shapes of powder obtained by the above method can be used instead of the substantially spherical powder employed in the embodiment. The reason for employing a magnetic powder other than a substantially spherical shape is to use anisotropy due to its shape, for example. More specifically, for example, non-spherical, flat, or needle-shaped magnetic powder is mixed with a resin, and a predetermined magnetic field is applied before the resin is cured to perform anisotropic orientation of the powder group. The use method of hardening the resin after that can be considered.

  As a specific demonstration model, a method was adopted in which magnetic powder was mixed with a thermosetting epoxy resin to form a slurry and poured into a predetermined case under reduced pressure. In the slurry for the magnetic core used in this, (1) optimization of the particle size of the magnetic material and (2) selection of the non-magnetic powder were performed in order to obtain high filling and high superposition characteristics of the magnetic material powder. The binder resin was selected by selecting a low viscosity (80 ° C., 70 mPas or less) by combining the main agent and the curing agent. That is, a composite magnetic material was produced by highly filling and uniformly dispersing magnetic powder in a low-viscosity epoxy.

  Since epoxy resin as a resin is required to be liquid and have low viscosity, compatibility with additives, curing agents and catalysts, and storage stability are also important characteristics that should be considered in selecting specific epoxy resins. . In consideration of such circumstances, epoxy resins such as bisphenol A type, bisphenol F type, and polyfunctional type can be used as the main agent, and aromatic polyamine type, carboxylic acid anhydride type, latent curing agent as the curing agent. A system type can be used. In this example, a combination of a bisphenol A type epoxy resin and a solvent-free low viscosity liquid aromatic amine curing agent was used.

  The first resin may be another thermosetting resin such as a silicone resin, or may be cured without applying heat such as a chemically reactive curable resin, an ultraviolet curable resin, or a photocurable resin. A curable resin may be used. Moreover, when it becomes press molding, the thermoplastic resin containing nylon, phenol, etc. which show the characteristic of a low viscosity at a certain pressure and temperature may be sufficient. Further, a base oil and a gelling agent having an appropriate melting point may be used. That is, any resin that acts as a binder between powders in the composite magnetic material is an object.

  Conventionally, for example, in order to manufacture a wire-inner-type wire ring part having an outer volume of about 300 cc with Sendust green compact by press molding, a 1000-ton scale press facility is required. When the casting method is selected, the cost of trial production and capital investment can be suppressed. As one means, we selected a direct casting method for product cases or separable cases using a fluid composite material. This method has sufficient advantages even if it is inferior in terms of the filling rate of magnetic powder compared with press molding, and as shown below, this method has a sufficient filling rate of composite magnetic The body can be obtained, and a wire-wrap type wire ring component with sufficient characteristics can be provided.

In the present invention, studies were conducted with the goal of finding a composite magnetic material that increases the magnetic permeability of the following magnetic field regions H1, H2, and H3.
H0 = 5A / m (Set the minimum magnetic field of the LCR meter to measure the initial permeability)
H1 = 15.92 kA / m
H2 = 31.84 kA / m
H3 = 79.6 kA / m

  The component of the magnetic core can be appropriately changed in the applied magnetic field used above. For example, in order to slightly increase the initial permeability, a high permeability thin film layer may be formed on the surface of the magnetic powder. Here, an example of the high magnetic permeability thin film is an Fe—Ni thin film. In order to avoid an electrical short circuit due to the magnetic powder, the magnetic powder may be coated with one or more insulating layers before being mixed with the resin. Here, when a high permeability thin film is formed on the surface of the magnetic powder, an insulating layer is coated on the formed high permeability thin film.

  Furthermore, it is preferable to add a non-magnetic powder to the mixture of the magnetic powder and the resin in order to ensure a high relative permeability in a higher magnetic field. Non-magnetic powders include, for example, inorganic powders made of silica powder, alumina powder, titanium oxide powder, quartz glass powder, zirconium powder, calcium carbonate powder, aluminum hydroxide powder, glass fiber, and granular resin. Can be mentioned. Further, a hollow glass sphere may be used as the nonmagnetic powder. Further, in order to extend the direct current superposition characteristics well into a higher magnetic field, a small amount of permanent magnet powder may be added to apply a magnetic bias to the magnetic core.

  Next, an embodiment of powder selection will be shown. As the magnetic powder, a 6.5% Si—Fe powder having an average particle diameter D50 = 160 μm was used and subjected to silane coupling treatment. The amount of silane coupling at this time was set to the minimum amount that can be slurried with a solidifying resin described later. This is because a silane coupling agent that does not contribute to bonding causes a decrease in adhesive strength, glass transition temperature, and the like.

  Next, using a thermosetting low-viscosity epoxy resin, mixing and defoaming were carried out, and a slurry serving as a base of a composite magnetic material having a viscosity of 30 P (poise) at 80 ° C. was prepared. It was cast into a 11 mm thick silicone mold and then cured at 115 ° C. for 4 hours. After measuring the density of the toroidal core of the cured product, 23 turns were wound with a φ1.5 mm wire, and the direct current superposition characteristics were confirmed. The viscometer (HADV-1 +, manufactured by Brookfield) was a screw head type (PC-1TL, manufactured by VISCOMETER).

  Here, the composition of the magnetic powder was 6.5% Si—Fe powder having the highest magnetostriction and the highest saturation magnetic flux density, but the difference in particle shape was examined using powders having different production methods. When water atomized powder, gas atomized powder and pulverized powder are compared as production methods, the gas atomized powder has the highest filling rate. Regarding the filling rate that can be made into a slurry, the filling rate of the pulverized powder was only 58.6 vol%, and the filling rate of the gas atomized powder having the same average particle diameter was 63.6 vol%. Since the gas atomized powder is spherical, in the case of the casting type, the filling rate can be increased by using the spherical powder.

  Furthermore, in order to investigate the relationship between the filling rate and the powder particle size distribution for the magnetic powder, the powder with an average particle diameter D50 = 160 μm, which is increased in gas atomization, is classified by a sieve having openings of 150 μm and 75 μm. Two types of powders with particle sizes were prepared. The cumulative particle size fraction and frequency distribution of the mother powder used for this are shown in FIGS.

  In both powders having a particle size of 150 μm or more and powders having a particle size of 75 to 150 μm, the filling rate was lowered to 60 vol%, but became a high-viscosity paste and could not be slurried. The reason for this is thought to be that narrowing the particle size distribution caused a decrease in the filling rate.

  As shown in FIG. 2, the mother powder can be considered as a distribution sum of a distribution of D25 = 110 μm peak and a distribution of D75 = 230 μm peak.

  FIG. 3 shows a relationship between the particle size ratio, the mixing ratio, and the filling rate in a large and small two-component particle mixed packed layer as an example of a true spherical packing model. FIG. 3 is data presented by Michitaka Suzuki: Himeji Institute of Technology, Powder and Particle Engineering Laboratory. When large particles and small particles are mixed and mixed, the small particles enter the gaps between the large particles, so the gaps are reduced and the particles are packed more densely. As shown in FIG. The rate increases. Moreover, there is a peak in which the filling rate increases on the side where the mixing ratio of the small particle size powder is smaller as the particle size ratio is larger. Therefore, in order to obtain a high filling rate, it is effective to add a small amount of fine powder having greatly different particle sizes. In other words, it is effective to widen the particle size distribution. In the case of the above classified powder, it is considered that the particle size distribution was narrowed, which led to a decrease in the filling rate.

  In this case, the filling rate that can actually be made into a slurry is 63.6 vol%, which is less than the filling rate of about 74% that is expected when it is composed of only ideal primary spheres. Thus, it is considered that the fact is that the sphericity variation of the atomized powder and the width of the particle size distribution actually exist. In addition, since the surface of the magnetic powder surface is not smooth, agglomeration and bridges are likely to occur between a certain particle and a plurality of particles. In order to reduce the probability of occurrence, a low viscosity (low friction) is required in the process of uniform dispersion and molding.

  The present invention relates to a magnetic core for inductors such as choke coils and transformers used in electronic equipment up to several hundred kHz. As an example, it is desired to determine whether or not there is a problem of eddy current loss of the inductor at the drive frequency f = 10 kHz. Here, the driving frequency f = 10 kHz of the product, the relative permeability μ of the powder composition μ = 1000, and the specific resistance ρ = 80 μΩcm of the powder composition bulk are used as constants.

When the skin depth δmm = (2 / (2πfμσ)) ^0.5 is calculated, the skin depth is 0.14 mm, and the corresponding particle diameter is 0.28 mm. The average particle size (D50) of the currently used dust material is about 0.16 mm, and D90 is about 0.28 mm. From the above, it seems that there is almost no influence of the skin effect. Further, the frequency characteristic of μ does not decrease at 10 kHz, and the influence of the skin effect is sufficiently small, but the particle size of 280 μm or more may be affected. Thus, it is desirable that the maximum particle size of the magnetic powder is appropriately selected according to the drive frequency.

  Highly filled and highly superimposed magnetic cores can be obtained by adding secondary and tertiary particles of small diameter spheres. Here, the secondary and tertiary particles of the small-diameter sphere can be classified into a case where magnetic powder is used and a case where nonmagnetic powder is used.

  First, when using a second magnetic powder having a smaller diameter, that is, as an example of high packing only with magnetic powder, adding magnetic powders having different particle sizes as secondary particles and tertiary particles at various blending ratios. Tried. The particle size of the additive powder is a spherical powder with secondary particles D50 = 9.8 μm and tertiary particles D50 = 1.0 μm. All the powders used are substantially spherical. The result is shown in FIG. FIG. 4 shows the filling rate when secondary particles (D50 = 9.8 μm) and tertiary particles (D50 = 1.0 μm) are added to primary particles (D50 = 160 μm) at various blending ratios. is there.

  The particle size was selected with the aim of achieving an effect that the filled powder dispersed in the epoxy resin was rearranged to facilitate high filling. From FIG. 4, the change of the filling rate with respect to the addition amount of the secondary particles shows a tendency to have one maximum value in a small proportion of fine particles as shown in FIG. However, the effect of adding the tertiary particles tends to have two peaks. In the mixing experiment of the powder having a sharp particle size in FIG. 3, it is shown that the effect of improving the filling rate is more remarkable when the particle size ratio is larger, that is, by adding finer particles. It seems that the degree of this effect is different in the powder having a broad particle size actually used. However, as shown in FIG. 4, it can be seen that an admixture with a high filling rate can be obtained by adjusting the particle size distribution.

  The inductance and its direct quantity superposition characteristics were evaluated at three representative locations in the region shown in FIG. Table 1 shows the blending ratio and results of the magnetic powder. In this specification, the blending ratio of powders and the like is expressed in vol%. As a reference for the vol%, the mixture obtained by mixing and curing the powder and the resin is set to 100 vol%, and the volume percentage of each powder and the like is calculated. As shown.

  As a result of the three types of blending, the magnetic permeability was measured as Sample No. A in the A region. 1, μ (H0) = 43.4, μ (H1) = 22.4, sample No. 2 gave a value of μ (H2) = 18.9. That is, the composite magnetic material that can be further miniaturized by the magnetic fields H0 = 5 A / m and H1 = 15.92 kA / m is the A region, and the composite magnetic material that can be further miniaturized by the magnetic field H2 = 31.84 kA / m is the B region. It is obtained with.

  Sample No. B in the B region As shown in FIG. 3, the reachable packing ratio with only the primary particles (D50 = 160 μm) is 63.6 vol%. Next, in order to perform gap filling, the filling rate can be made 74.6 vol% by adding 11 vol% of secondary particles (D50 = 10 μm). Furthermore, secondary particles (D50 = 10 μm) and 14 vol% of tertiary particles (D50 = 10 μm) are added together with 13 vol%, so that the filling rate can be 78.6 vol%.

  As described above, the magnetic field H0 = 5 A / m, H1 = 15.92 kA / m, H2 = by using the second magnetic powder having a smaller diameter (secondary and tertiary particles made of a magnetic powder having a small sphere). The magnetic permeability of the magnetic core at 31.84 kA / m can be increased.

  Next, as another example capable of obtaining a magnetic core having high filling and high superposition characteristics, when using a non-magnetic powder having a smaller diameter, that is, using a non-magnetic powder as secondary and tertiary particles of a small sphere Is described. First, the first magnetic powder and nonmagnetic powder were selected. The nonmagnetic powder used was an inorganic powder such as silica or alumina whose particle size can be changed over a wide range.

  First, as the first magnetic substance powder, the same 6.5% Si—Fe powder having an average particle diameter D50 of 160 μm as described above was used and subjected to silane coupling treatment.

  Next, as an inorganic powder silica, the sintering powder is an agglomerated particle when viewed with an electron microscope SEM, and has a specific surface area of 7 times or more compared to the spherical powder, and the resin component is easily absorbed. It is thought that the component will decrease. For this reason, although the powder for sintering is low-cost, it is difficult to obtain the effect of improving the filling rate of the present application.

  Furthermore, three kinds of other spherical powder, roundish powder and pulverized powder were compared. These powders were added in 3, 5, and 10 vol%, respectively, and the first magnetic powder amount was adjusted so that the total amount with the magnetic powder was 60 vol%. As a result, both the roundish powder and the pulverized powder could not be slurried. Therefore, it can be seen that it is desirable to use spherical powder in order to obtain the effect of improving the filling rate.

The results using spherical silica powder are shown below.
Table 2 shows the results obtained by selecting spherical silica having an average particle diameter D = 2.5 μm as secondary particles and spherical silica having an average particle diameter D50 = 2.5 μm as secondary particles, and adding these selected silicas in combination. Shown in

  It was confirmed that the relative magnetic permeability μ changes depending on the particle size and the added amount of the fine powder. The permeability of the sample No. 4 gives a value of μ (H3) = 7.6.

  That is, the magnetic permeability at the magnetic field H0 = 5 A / m, H1 = 15.92 kA / m, and H2 = 31.84 kA / m after the addition is smaller than before the nonmagnetic powder addition (sample No. 3). Show. However, it can be seen that a higher magnetic permeability is exhibited at the magnetic field H3 = 79.6 kA / m.

  Furthermore, the sample No. As shown in FIG. 4, the secondary particles (D50 = 2.5 μm) are 5.5 vol% and the tertiary particles (D50 = 0.5 μm) are 5.5 vol% with respect to the primary particles (D50 = 160 μm). By adding them together, the filling rate can be 72.2 vol%.

  Sample No. B in the B region The result of examining the density distribution of the molded body of No. 3 will be described. In order to confirm the non-uniformity, the method and results of measuring the upper and lower density distribution of the cured product are shown. As a method, the slurry is cured in a syringe having a depth of about 45 mm and a diameter of 23 mm, and two portions of about 5 mm from the bottom and the surface of the cured product are cut into three cylinders. The weight of each cylinder, the average diameter, The average height was measured, and the average density of each cylinder was calculated from the weight and volume.

As a result, the density of the portion about 5 mm from the surface was low and the density of the portion about 5 mm from the bottom was high as described below.
a) A portion approximately 5 mm from the surface 5.17 g / cc (5% lower than the center ratio)
b) Center portion 5 to 37 mm portion 5.44 g / cc
c) About 5 mm from the bottom 5.71 g / cc (5% higher than the center)

  This phenomenon is caused by the particles being settled before the resin matrix of the admixture reaches heat curing, and the filling rate is locally improved, resulting in a heterogeneous structure of the magnetic core. This indicates that the direct current superimposition characteristic may be deteriorated. That is, from the results so far, it is considered essential to suppress precipitation of magnetic particles or non-magnetic particles in order to further improve the direct current superposition characteristics.

This will be discussed in more detail.
With respect to the target direct current superposition characteristics, it can be expected that the size of the micro gap formed between the individual particles varies depending on the location even if the filling rate of the magnetic powder is the same. FIG. 5 is a schematic view showing a dispersed state of the magnetic powder. A circle indicates a magnetic powder. In other words, if the magnetic powder (circles) as shown in FIG. 5 is uniformly dispersed, the average demagnetizing field should not be reduced, and a characteristic that is difficult to cause magnetic saturation should be obtained. is there. However, if the filling rate of magnetic powder (marked with ○) that indicates inappropriate is locally increased, the microgap between particles in such a place becomes smaller, resulting in a smaller demagnetizing field and a tendency to magnetic saturation. Become. Therefore, it is considered that eliminating such non-uniform distribution of the magnetic powder leads to higher characteristics. As one of the measures, it is considered effective to suppress the sedimentation of the magnetic powder that occurs during resin curing.

  As a measure for reducing the sedimentation rate of the particles, it is conceivable to increase the viscosity of the slurry. It is thought that it can be achieved simply by adding a thickener. However, since the casting method requires an operation of pouring the slurry into the mold, it is necessary that the viscosity is sufficiently lowered during the casting operation. Therefore, it is desirable to be able to utilize a property such as thixotropic in which the viscosity is reduced by applying shear or vibration. Therefore, a thixotropic agent is preferably used for uniform dispersion of the magnetic powder.

  Nano-sized fine particle anhydrous silica called nano silica is widely used in the adhesive industry as a highly active filler for increasing viscosity and imparting thixotropic properties. Silanol groups on the surface of nanosilica having a primary particle size of several nanometers are linked to the surface of the adjacent nanosilica by hydrogen bonding, form a three-dimensional network structure, and exhibit excellent viscosity. This hydrogen bond is a relatively weak bond, and by applying a slight shearing force (for example, vibration and stirring), the network structure is broken, broken up in units of chain-bonded particles, and loses viscosity. Due to this decrease in viscosity, good filling properties and rearrangement of fillers can be performed. On the other hand, in a stationary state, the mesh structure is regenerated, the viscosity is restored, and the sedimentation rate can be suppressed.

  These phenomena are called thixotropy phenomena and are important characteristics that improve the production and storage of magnetic slurries, as well as process capability and product properties.

  The thixotropic nature mainly depends on the resin used. For this reason, as a result of trying nano silica with different surface treatments, the most effective ones were those with a particle size of 4-7 nm and surface treatment with hydrophobic dimethyl silicone oil, which provided thixotropic properties. It was. The results using this nanosilica are shown in Table 3.

  As a result of three levels of nanosilica addition, nanosilica 0.27 vol%, and nanosilica 0.53 vol%, the permeability was 0.27 vol% of nanosilica and μ (H0) = 13.7, μ (H1) = 13 .Mu. (H2) = 12.0, nanosilica added at 0.58 vol%, a value of .mu. (H3) = 9.0 was obtained.

  That is, when the magnetic fields H0 = 5 A / m, H1 = 15.92 kA / m, and H2 = 31.84 kA / m, the composite magnetic material that can be made smaller is 0.27 vol% nanosilica (sample No. 5 in the A region). In addition, in the magnetic field H3 = 79.6 kA / m, the composite magnetic material that can be further miniaturized is one with 0.58 vol% nano silica added (sample No. 6 in the A region). In particular, the value of μ (H3) = 9.0 is the maximum value obtained by experiments in the magnetic field H3 = 79.6 kA / m. ,

  Thus, regarding the direct current superposition characteristics in the high magnetic field H3, the effect by adding nano silica is great. However, with respect to the filling rate, the presence or absence of the addition of nano silica is not so large. As shown in Table 3, the filling rate is 71.1 vol% with addition of 0.27 vol% of nanosilica and 68.4 vol% with addition of 0.58 vol% of nanosilica with respect to 72.2 vol% without addition of nanosilica. .

  As described above, the magnetic permeability of the magnetic field H3 = 79.6 kA / m can be increased by using non-magnetic powder (silica) as the secondary and tertiary particles of the small-diameter sphere and further using nano silica. That is, by adding nano silica, thixotropic properties are imparted, and the non-uniform distribution of the magnetic powder can be eliminated and the magnetic permeability can be improved by the sedimentation suppressing effect.

  When nanosilica is added, thixotropic properties are exhibited. Therefore, when casting is performed, it is preferable to perform casting while applying an appropriate stirring energy and vibrating. In principle, the hydrogen bond of nano silica is a relatively weak bond and loses its viscosity by applying a slight shearing force (for example, vibration, stirring).

  For this reason, the stirring conditions of the slurry were changed to 5 minutes, 15 minutes, and 20 minutes at a high speed stirring of 2000 rpm, which is considered to be the upper limit from the viewpoint of wear of the blades (diameter 50 mm) during mass production. As a result, it can be seen that Δμ / μ0, which is an index of the direct current superposition characteristic, takes a substantially constant value for 15 minutes or more, and this stirring condition may be adopted for 15 minutes or more.

  The casting was performed in a vacuum of 2700 Pa after deaeration of the stirred slurry at 50 Pa. Moreover, casting was performed while applying 50 Hz vibration with a vibrator (av-02: manufactured by Murata Seiko Co., Ltd.). Stop vibration and release to atmosphere after casting. Immediately after that, it was cured by heat treatment in a stationary state.

  FIG. 6 shows a similar system of flow / viscosity curves of an epoxy resin whose thixotropy is improved by adding nano silica. This is the result of measuring the ease of flowing at 50 ° C. isothermally during curing of the epoxy resin. A Brookfield rotational viscometer rotating at 2.5 rpm and a vibrator as a shearing force source are used. From this result, it can be seen that it is necessary to cast while applying a shear rate for uniform rearrangement of magnetic powder. In this study, it can be seen that by setting the vibration frequency of the vibrator to 50 Hz, the viscosity is substantially minimized and the rearrangement of the particles is facilitated. In addition, the shear rate is quickly reduced to zero after the slurry magnetic body is filled. By doing in this way, the viscosity of the slurry magnetic body shows a maximum value, and the sedimentation speed can be minimized.

  In the present embodiment, it is possible to form a magnetic core of a composite magnetic material that does not lower the permeability in a high magnetic field only by selecting the shape of the casting container. If this degree of freedom of shape is used, a wire ring part having a spherical product shape can also be manufactured.

  Furthermore, by arranging a specific permeability magnetic core member in the casting container and casting the mixture, a magnetic core made of a composite magnetic material partially incorporating the specific permeability core member is formed. Can do.

  For example, a specific permeability magnetic core member is arranged in a part of a magnetic core made of a mixture having a relative permeability μdc of 20 in a 7.96 kA / m magnetic field. Here, when a cylindrical magnetic core having a specific magnetic permeability core member having a specific magnetic permeability μdc of 30 in a magnetic field of 7.96 (kA / m) and having a half of the total magnetic core volume is incorporated, the built-in magnetic core The relative permeability in a 7.96 kA / m magnetic field increases from 20 to 23.

  Similarly, for example, a specific permeability magnetic core member is disposed in a part of a magnetic core made of a mixture having a relative permeability μdc of 20 in a 3.98 kA / m magnetic field. Here, when a cylindrical magnetic core half of the total magnetic core volume made of a specific magnetic permeability core member having a relative magnetic permeability μdc of 70 in a magnetic field of 3.98 kA / m is incorporated, 3 of the incorporated magnetic cores. The relative permeability in a .98 kA / m magnetic field increases from 20 to 30.

  Furthermore, when a specific permeability magnetic core member having a relative permeability μdc = 1 is inserted into a part of the magnetic path, there is an advantage that the inductance of the winding component is less likely to be saturated even in a high magnetic field. The resin used for the specific permeability magnetic core member in this case is desirably the same resin as the insulating resin used for the winding inclusion insulator. The specific permeability magnetic core member having a lower magnetic permeability is also preferably, for example, the same resin as the insulating resin used for the winding inclusion insulator, or the same resin mixed with a nonmagnetic filler. In addition, the high magnetic resistance member is, for example, a predetermined amount with respect to the same resin as the insulating resin used for the winding inclusion insulator (as a result, the magnetic resistance of the high magnetic resistance member is higher than the mixture). It may be formed of a mixture of magnetic powder.

  The specific permeability magnetic core member incorporated in a part of the magnetic core may be appropriately selected in terms of the magnetic permeability of 1 or more and the shape as appropriate according to the magnetic field to be used. That is, it is possible to easily form a form that encloses the specific magnetic permeability core member. Although any shape can be selected as the magnetic core shape, it goes without saying that a toroidal magnetic core shape having a uniform magnetic path is ideal in theory. Such a uniform magnetic path shape is advantageous in terms of reducing leakage magnetic flux and ensuring magnetic permeability.

  In addition, regarding the winding, the integral configuration of the winding inclusion insulator and the magnetic core according to the present invention is a configuration in which a breakdown voltage failure due to a pinhole is likely to occur. In conventional inner iron type wire ring parts, measures are taken by bobbin, varnish impregnation and powder coating, but it is desirable to carry out by a method which is less likely to contain bubbles. Since the powder coating method is performed at normal pressure, there is a surface in which voids are generated between the coil wires and pinholes are easily generated. For this reason, in the case of the present invention, for the impregnation and adhesion between the coils and between the coil pedestals, the winding inclusion insulator is used by using an impregnation / adhesive in which an inorganic filler is uniformly dispersed in a thermosetting epoxy resin. It is desirable to manufacture.

  The wire ring component of the present invention is manufactured by placing a coil-containing insulator and a specific permeability magnetic core member in a mold, and casting and curing an admixture combined with a releasable resin to produce a magnetic core. Can be manufactured by removing the mold. Moreover, the wire ring component provided with the case can also be manufactured. By using part or all of the mold as a case, it is possible to manufacture without removing the mold. When the mold is not removed, it is not necessary to consider releasability, so that it is easy to manufacture a magnetic core having a complicated shape.

  Furthermore, a case that functions as a magnetic core may be used. For example, when a case functioning as a magnetic core is used as a common part with other parts, it is effective in a case where a winding part is once formed and then the winding part is placed in a case that is a common part. This case may be formed of other magnetic materials / alloys such as Fe-Ni alloys. When the case is made of a magnetic material, in order to ensure appropriate insulation performance, it is preferable to form an insulating film on the inner surface of the case and then cast the mixture to form a magnetic core. The case may be a ceramic case such as an alumina molded body, or may be made of an aluminum alloy.

  It is possible to provide a wire ring component that includes the case as described above and in which a winding inclusion insulator and a magnetic core made of the mixture fill a space between the case.

  According to Ollendorff's approximation, the DC permeability μdc can be expressed as shown in Equation 1 as a function of the demagnetizing factor N of each particle and the volume filling factor η.

数１の右辺の材料透磁率μについては、６．５％Ｓｉ−Ｆｅ多結晶材のμ＝２３０００を用いた。

As for the material permeability μ on the right side of Equation 1, μ = 23000 of 6.5% Si—Fe polycrystalline material was used.

  Next, the demagnetizing field of individual particles in each of the super E core (a laminated core using a 0.1 mm foil strip provided with a magnetic gap), the dust core, and the composite core of the magnetic powder and resin of the present invention The coefficient N was calculated using the above approximate expression. The results are shown in Table 4. The composite magnetic core of the magnetic powder and resin of the present invention calculated the demagnetizing factor for the magnetic powder blend and the nanosilica and non-magnetic powder blend.

  Thus, even if the raw material is the same 6.5% Si—Fe polycrystalline material, the smaller the demagnetizing factor N of each particle, the larger the magnetic permeability. The spherical demagnetizing factor is theoretically 1/3, but the calculated data shows a lower value. It is estimated that the reason why the calculated value is lower is that aggregation and bridging thereof are likely to occur between a certain particle and a plurality of particles. In the present embodiment, the demagnetizing factor of the calculated value is 0.12 or less, but considering the product shape and process capability, it is considered that the range of the semimagnetic factor is preferably N <= 0.4 in the present invention. It is done.

Cumulative particle size fraction based on volume of mother powder. Frequency distribution of the volume-based particle size of the mother powder. The relationship between the particle size ratio, the mixing ratio, and the filling rate in the large and small two-component particle mixed packed bed. This figure is data released by Michitaka Suzuki: Himeji Institute of Technology Filling rate when secondary particles (D50 = 9.8 μm) and tertiary particles (D50 = 1.0 μm) are added to primary particles (D50 = 160 μm) in various mixing ratios. The schematic diagram which shows the dispersion state of a magnetic body powder. An analogous system of the flow / viscosity curve of an epoxy resin with improved thixotropy by adding nanosilica is shown.

Claims (24)

A wire ring component using a magnetic core obtained by solidifying or curing an admixture of a first magnetic powder, a smaller second magnetic powder or non-magnetic powder, and a resin, The magnetic core has a relative permeability μdc in a magnetic field of 7.96 kA / m of 10 or more, and an effective demagnetizing factor N of the first magnetic powder is 0.4 or less. The total filling ratio of the magnetic powder of 1 and the second magnetic powder or the non-magnetic powder having a smaller diameter is 50 vol% or more, and the average particle diameter φ1 of the first magnetic powder is as described above. The average particle diameter φ2 of the second magnetic powder or the nonmagnetic powder having a small diameter is φ2 = <φ1 / 15, and the volume fraction of the second magnetic powder or the nonmagnetic powder having a smaller diameter is 40 vol. %, And further comprising nano-sized anhydrous silica Goods.   The wire ring component according to claim 1, wherein the magnetic core has a relative permeability μdc of 2 or more in a magnetic field of 31.84 kA / m.   The wire ring component according to claim 1, wherein the magnetic core has a relative permeability μdc in a magnetic field of 79.6 kA / m of 2 or more.   4. At least one part of the coil | winding inclusion insulator obtained by enclosing with insulating resin so that the edge part of a coil | winding may be remove | excluded is embedded in the said magnetic core. The wire ring component described.   4. The all-winding insulating material obtained by surrounding with an insulating resin so as to exclude the end of the winding is embedded in the magnetic core according to claim 1. Wire ring parts. Senwa component according to any one of claims 1 to 5 second magnetic powder or nonmagnetic powder smaller than before SL is characterized in that it is a substantially spherical powder. 7. The wire ring according to claim 1, wherein less than half of the second magnetic powder or the non-magnetic powder having a smaller diameter is a powder having a particle diameter of φ 1/50 or less. parts. 5. The coil-containing insulator is obtained by uniformly impregnating with a mixture of at least the nano-sized anhydrous silica- containing insulating nonmagnetic powder and resin, and solidifying or curing. The wire ring part according to any one of 5.   The wire ring component according to any one of claims 1 to 7, wherein the magnetic powder is made of soft magnetic powder.   The wire ring component according to any one of claims 1 to 7, wherein the magnetic powder includes at least a soft magnetic powder.   The wire ring component according to claim 9, wherein the soft magnetic powder includes at least an Fe—Si based powder.   The wire ring component according to claim 11, wherein the average Si content in the Fe—Si-based powder is 11.0% by weight or less (not including 0% by weight).   The wire ring component according to claim 9, wherein the soft magnetic powder includes at least a Fe—Si—Al-based powder.   The average Si content in the Fe—Si—Al-based powder is 11.0% by weight or less (not including 0% by weight), and the average Al content is 7.0% by weight or less (not including 0% by weight). The wire ring component according to claim 13, wherein:   The wire ring component according to claim 9, wherein the soft magnetic powder includes at least an Fe—Ni-based powder.   The wire ring component according to claim 15, wherein an average Ni content in the Fe—Ni-based powder is 30.0 wt% or more and 85.0 wt% or less.   The wire ring component according to claim 9, wherein the soft magnetic powder includes at least an amorphous powder.   The wire ring component according to claim 9 or 10, wherein the soft magnetic powder contains at least carbonyl iron powder.   The wire ring component according to any one of claims 1 to 18, wherein the second magnetic powder or the non-magnetic powder having a smaller diameter includes at least a substantially spherical powder.   The specific permeability magnetic core member is a wire ring component embedded in the magnetic core, and the specific permeability magnetic core member has a relative permeability μdc in a magnetic field of 7.96 kA / m of 1 or more. The wire ring component according to any one of claims 1 to 19, wherein the wire ring component is characterized by the following.   The specific permeability magnetic core member is a wire ring component embedded in the magnetic core, and the specific permeability magnetic core member has a relative permeability μdc in a magnetic field of 3.98 kA / m of 1 or more. The wire ring component according to any one of claims 1 to 19, wherein the wire ring component is characterized by the following.   The wire ring component according to any one of claims 1 to 19, wherein a specific permeability magnetic core member having a relative permeability μdc of 1 is embedded in a part of the magnetic core.   The wire ring component according to any one of claims 1 to 19, wherein a magnetic material processed component is embedded in a part of the magnetic core.   The wire ring component according to any one of claims 1 to 23, further comprising a holding case, wherein at least a part of the mixture is solidified or hardened in the case.

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