JP2006237209A - Common mode choke coil - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a common mode choke coil having an extended resonance frequency and can be used in high frequency region. <P>SOLUTION: The common mode choke coil, i.e. a coil component 1, comprises a drum type magnetic core 2. Two wires 6 and 7 are wound around the core portion 3 of the magnetic core 2. These wires 6 and 7 are coated wires produced by coating conductors, e.g. copper wires, with mixed resin containing an insulating material, i.e. silicon modified epoxy resin. In the mixed resin, thermosetting resin is a compound resin of epoxy resin and silicon resin and contains silicon modified epoxy resin. Silicon modification rate of epoxy resin is 5-30%. Dielectric constant is 2.0-3.0. <P>COPYRIGHT: (C)2006,JPO&NCIPI

Description

  The present invention relates to a common mode choke coil, and more particularly to a common mode choke coil that includes a core, a conducting wire, and a terminal electrode, the conducting wire wound around the core is covered with insulation, and the conducting wire is connected to the terminal electrode.

  2. Description of the Related Art Conventionally, a common mode choke coil has been known in which a drum-type core is covered with a coated conductor wire that is insulated. Specifically, the common mode choke coil includes a drum type core and a plurality of coated conductors. The drum type core includes a pair of flange-shaped flange portions and a core portion, and the core portion connects the pair of flange portions to each other. The plurality of coated conductive wires are wound around the core of the drum type core, respectively.

Each flange portion is provided with a number of terminal electrodes corresponding to the number of the plurality of coated conductors. One end of each of the plurality of covered conductors is connected to each terminal electrode of one flange portion, and one end of each of the plurality of covered conductors is connected to each terminal electrode of the other flange portion. They are connected one by one. A portion between one end and the other end of the plurality of covered conductors forms a winding portion wound around the core portion. The insulating coating is made of polyurethane resin. The common mode choke coil having such a configuration is described in, for example, Japanese Patent Laid-Open No. 2000-208331 (Patent Document 1).
JP 2000-208331 A

  Since the conventional common mode choke coil is made of polyurethane resin as described above, the dielectric constant of the insulating coating is as high as about 4, and it is difficult to increase the resonance frequency. In addition to the polyurethane resin, polyimide amide, polyester, and the like are used. In any case, the dielectric constant of the insulating coating is as high as about 4, and it is difficult to increase the resonance frequency.

  Accordingly, an object of the present invention is to provide a common mode choke coil which has a high resonance frequency and can be used in a high frequency region.

  In order to achieve the above-mentioned object, the present invention provides a core, a coated conductor wire that is insulated and wound around the core, a terminal electrode having a connecting portion that is connected to the coated conductor wire, and a user terminal. A common mode choke coil is provided. The insulating coating has a modified epoxy resin and a relative dielectric constant of 2.0 to 3.0.

  Since the insulating coating has the modified epoxy resin and the relative dielectric constant is 2.0 to 3.0, the resonance frequency can be increased and the high frequency characteristics can be improved. Moreover, even when the variation in the distance between the coated conductors wound around the winding core portion occurs, the variation in the capacitance between the coated conductors can be reduced.

  Here, the insulating coating is composed of a composite resin of an epoxy resin, a silicone resin, and an epoxy resin curing agent, and the modified epoxy resin is a silicone-modified epoxy resin obtained by modifying the epoxy resin with the silicone resin. Is preferred.

  Since the modified epoxy resin is a silicone-modified epoxy resin in which the epoxy resin is modified with a silicone resin, the relative dielectric constant can be easily adjusted to 2.0 to 3.0.

  The composite resin has a weight ratio of the epoxy resin to the silicone resin of x /, where x is the chemical equivalent of the epoxy resin obtained by dividing the average molecular weight by the functional group, and y is the chemical equivalent of the silicone resin. It is preferable that they are mixed at a value exceeding y. Since the weight ratio of the epoxy resin to the silicone resin is mixed at a value exceeding x / y, the silicone modification rate of the epoxy resin in the composite resin can be easily in the range of 5 to 30%. .

  Moreover, it is preferable that the silicone modification rate of the epoxy resin in the composite resin is in the range of 5 to 30%. Since the silicone modification rate of the epoxy resin in the composite resin is in the range of 5 to 30%, the relative dielectric constant can be set to 2.0 to 3.0.

  As described above, it is possible to provide a common mode choke coil which has a high resonance frequency and can be used in a high frequency region.

  The coil component according to the first embodiment of the present invention will be described with reference to FIGS. The coil components according to the present embodiment described below are specifically common mode choke coils used for high-speed operation signal interfaces. The coil component 1 includes a drum-type magnetic core 2 as shown in FIG. 1 and has a size of about 2 mm in the long side direction and about 1.2 mm in the width direction. The magnetic core 2 is formed by compressing or sintering magnetic powder such as ferrite.

  The magnetic core 2 includes a core portion 3 having a substantially rectangular cross section perpendicular to the longitudinal direction, and a pair of flange portions 4 and 5 having substantially the same shape. Two conductors 6 and 7 are wound around the core 3. These conducting wire 6 and conducting wire 7 are covered conducting wires. As shown in FIG. 2, the conducting wire 7 is configured by covering a conductor 7A such as a copper wire with a mixed resin coating 7B containing a silicone-modified epoxy resin as an insulating material.

  Similarly, the conductor 6 is configured by covering a conductor (not shown) such as a copper wire with a mixture resin (not shown) containing a silicone-modified epoxy resin as an insulating material. The diameters of the lead wire 6 and the lead wire 7 are about 20 μm to 80 μm, respectively. The thickness of the lead wire 6, the coating (not shown) of the lead wire 7, and the thickness of the coating 7 B in the radial direction is, for example, about 2 μm to 5 μm. In the case of 80 μm, it is about 6 μm to 10 μm. The thickness of the coating is designed in consideration of pressure resistance, heat resistance, wear and the like. However, the relative permittivity increases as the coating becomes thicker. In this embodiment, including the first embodiment, the relative dielectric constant of the coating is about 2.0 to 3.0.

  The mixed resin containing silicone-modified epoxy resin that constitutes the conductor 6 and the conductor 7 (not shown) and the sheath 7B is a thermosetting resin and is in a semi-cured state. A curing agent is added to the thermosetting resin, and a varnish having an appropriate viscosity is obtained using a solvent or a plasticizer. The appropriate viscosity is a viscosity that is easy to adhere to the surface of the conductor 6, the conductor (not shown) of the conductor 7, and the conductor 7 </ b> A.

  The conductor (not shown) and the conductor 7A are attached, for example, by passing the conductor 6 and the conductor (not shown) of the conductor 7 and the conductor 7A through a container in which varnish is stored. After the varnish is attached to the electric wire body and the wire is covered, the curing reaction of the epoxy resin in the varnish is started while the solvent or the plasticizer is evaporated by heating. By appropriately setting the heating temperature and the heating time, the curing reaction is stopped halfway, and a so-called semi-cured state (also called a B stage) is obtained.

  Here, the semi-curing is described in, for example, “Plastic Materials Course [1] Epoxy Resin”, page 300, published by Nikkan Kogyo Shimbun, Inc., but reacts with a solid that is soluble and fusible. It is to stop. In thermosetting resins such as epoxy resins, the crosslinking reaction proceeds with a polymerization reaction, but the half-curing can be said to be a state in which the crosslinking reaction is partially stopped (partial crosslinking). The “semi-curing” in the present embodiment has a fusibility to be melted by heat at the time of soldering or welding as described later, but is not necessarily “soluble”.

  Also, the conductor 6, a coating (not shown) of the conductor 7, and a mixed resin containing a silicone-modified epoxy resin that constitutes the coating 7 B are other conductive parts, more specifically, a terminal electrode 8 A, a terminal electrode 9 A, and a terminal described later. When heat for soldering or welding is applied to the electrode 8B and the terminal electrode 9B, the conductor 6, the conductor (not shown) of the conductor 7, and the conductor 7A can be short-circuited to the other conductive parts. It has a melting point that melts. The temperature of soldering and welding of the conductive wire which is an insulation coating electric wire is generally 150 ° C. to 460 ° C. Accordingly, the melting point of the coating (not shown), the coating 7B, is lower than the temperature in this range. Since the coating (not shown) and the coating 7B are made of a plurality of materials as will be described later, the melting point is a so-called eutectic point. Further, since the melting point in this case is melting for soldering or welding to another conductive part, it may be lower than the melting point in a strict sense. That is, it may be sufficient if the coating 7B, not shown, which has been softened to some extent, can be separated by, for example, a soldering iron so that the conductor 6, the conductor 7A (not shown) of the conducting wire 7 can be exposed. In some cases, the melting point is lower than the meaning.

  In addition, the mixed resin including the conductor 6 and the unillustrated coating of the conductive wire 7 and the silicone-modified epoxy resin constituting the coating 7B is in a tack-free or non-fused state although the thermosetting resin is semi-cured. It has become. Tack-free is also called “finger touch drying” and means that even if it is touched with a human finger, it will not stick. Stickiness is whether or not material adheres to the finger touched. The “non-fused state” is a state where the materials are not fused when they are brought into contact with each other.

  Moreover, as for the mixed resin constituting the conductor 6 and the conductor 7 (not shown) and the sheath 7B, a thermosetting resin is provided in the form of a composite resin of an epoxy resin and a silicone resin. And this composite resin contains a silicone modified epoxy resin. The silicone-modified epoxy resin is an epoxy resin modified by reacting a silicone resin with a functional group of the epoxy resin. The silicone modification rate of the epoxy resin is about 5 to 30%. This is in consideration of insulation characteristics, heat resistance, flexibility (or flexibility), conductor 6, conductor 7 (not shown), adherence to conductor 7A (film-forming property), dielectric constant, etc. It is configured.

  The epoxy resin is good in terms of adherence to the conductor 6 and conductor 7 (not shown) and conductor 7A in a semi-cured state, and is excellent in insulation characteristics and heat resistance, but is flexible. In particular, there are some difficulties in terms of flexibility after the main curing. On the other hand, the silicone resin has no problem in terms of flexibility and is good in terms of insulation characteristics and heat resistance. However, when an insulating coating in a semi-cured state is formed only with silicone resin as in the present embodiment, the conductor 6, the conductor (not shown) of the conductor 7, and the conductor 7 A are not sufficiently deposited, and the conductor (not shown) There is a problem that a film cannot be successfully formed on the surface of the conductor 7A.

  Therefore, in this embodiment, as described above, a part or all of the epoxy resin is modified with a silicone resin to ensure flexibility, and a composite resin composed of them is semi-cured. ing. Specifically, the silicone-modified epoxy resin is semi-cured with a curing agent, and when an unmodified epoxy resin is contained, it is also semi-cured with the curing agent.

  This also applies to the following description. When the epoxy resin is “semi-cured” or “main cured”, only the silicone-modified epoxy resin is cured unless an unmodified epoxy resin is contained. However, if an unmodified epoxy resin is contained, the silicone-modified epoxy resin and the unmodified epoxy resin are cured.

  The epoxy resin used as the base material of the composite resin is bisphenol A type epoxy resin, bisphenol F type epoxy resin, bisphenol S type epoxy resin, phenol / novolak type epoxy resin, cresol / novolac type epoxy resin, biphenyl type epoxy resin, biphenol. Type epoxy resins, dimer acid-modified epoxy resins, halogenated epoxy resins, linear aliphatic epoxy resins, alicyclic epoxy resins, spirocyclic epoxy resins and the like can be used. About these epoxy resins, it can also be used individually by 1 type, and can also be used in mixture of 2 or more types.

  In many cases, a curing agent is added to the epoxy resin and cured. As the curing agent, an organic polyamine (for example, an aliphatic simple amine) or an organic acid (for example, phthalic anhydride) is used. About these hardening | curing agents, it can also be used individually by 1 type, and can also be used in mixture of 2 or more types.

  Moreover, an epoxy resin hardening accelerator may be used. The epoxy resin curing accelerator is not particularly limited and is appropriately selected depending on the epoxy resin used. For example, imidazole curing agent accelerators such as 2-methylimidazole, 2,4-dimethylimidazole, and 2-methyl-4-methylimidazole, and curing accelerators such as dicyandiamide, adipic acid dihydrazide, and melamine can be used. These curing accelerators can also be used singly or in combination of two or more.

  Moreover, as the silicone resin, a reactive silicone resin having a functional group such as an amino group, a hydroxyl group, or a carboxyl group can be used. These silicone resins can also be used singly or in combination of two or more.

  The silicone-modified epoxy resin can be obtained by mixing a silicone resin and an epoxy resin and heating to a predetermined high temperature for a predetermined time. In this embodiment, in particular, when the chemical equivalent of the epoxy resin obtained by dividing the average molecular weight by the functional group is x and the chemical equivalent of the silicone resin is y, the weight ratio of the epoxy resin to the silicone resin exceeds x / y. The one obtained by mixing with is used.

  When the epoxy resin and the silicone resin each have two functional groups, assuming that both the average molecular weight of the epoxy resin and the average molecular weight of the silicone resin are 1000, the chemical equivalent of the epoxy resin X = 500, the chemical equivalent of the silicone resin y = 500, and the weight ratio of the epoxy resin to the silicone resin is mixed at a value greater than x / y = 1.

  When mixed at such a weight ratio and sufficiently heated to cause complete reaction, in principle, the epoxy resin reacts with all functional groups of the silicone resin, and the unreacted silicone resin disappears. If a large amount of unreacted silicone resin remains, there is a problem that the adherence of the conductive wire 6 and the conductive wire 7 to the conductor (not shown) and the conductor 7A deteriorates, but this embodiment does not have such a problem.

  The average molecular weight includes number average molecular weight, weight average molecular weight, viscosity average molecular weight, and z average molecular weight (average molecular weight determined by ultracentrifugation), and any of them may be used. The average molecular weight may be measured by any of the boiling point raising method, freezing point depression method, osmotic pressure method, terminal group method, light scattering method, ultracentrifugation method, and viscosity method. The conductor 6 and the coating 7B (not shown) of the conductor 7 are mixed resin containing the silicone-modified epoxy resin as described above, and the silicone modification rate of the epoxy resin is set to 5 to 30%. About 0.0 to 3.0. For this reason, the resonance frequency of the common mode choke coil can be extended high, and the common mode choke coil can be used in a high frequency region.

  As shown in FIG. 3, the core part 3 is a substantially rectangular parallelepiped, and includes a top surface 3A, a bottom surface 3C that is a bottom surface of the top surface 3A, a side surface 3B that is a surface between the top surface 3A and the bottom surface 3C, and And a side surface 3D.

  The flange portion 4 is a substantially rectangular parallelepiped, and is connected to the top surface 4A, the top surface 4A, the inner side surface 4F that is a connection surface with the core portion 3, the front side surface 4E facing the inner side surface 4F, and the top surface The lower surface 4C is opposed to 4A, and the side surface 4D and the side surface 4B are surrounded by the top surface 4A, the inner side surface 4F, the lower surface 4C, and the front side surface 4E.

  The flange 4 is provided with a terminal electrode 8A at the end portion in the vicinity of the connection position between the top surface 4A, the front side surface 4E, the lower surface 4C, and the side surface 4B across the top surface 4A, the front side surface 4E, and the lower surface 4C. Similarly, across the top surface 4A, the front side surface 4E, and the lower surface 4C, a terminal electrode 9A is provided in the vicinity of the connection position between the top surface 4A, the front side surface 4E, the lower surface 4C, and the side surface 4D. These terminal electrode 8A and terminal electrode 9A are formed on the surface of the flange 4 by plating.

  Similarly to the flange portion 4, the flange portion 5 includes a top surface 5A, an inner side surface 5F, a side surface 5D, a front side surface 5E, a side surface 5B, and a lower surface 5C, and includes a terminal electrode 8B and a terminal electrode 9B, respectively.

  As shown in FIG. 4, the conducting wire 6 and the conducting wire 7 are drawn out from the vicinity of the coupling portion between the core portion 3 and the flange portion 4 and wired in the direction of the top surface 4A along the inner side surface 4F. It is bent along the top surface 4A at the intersection of 4A and the inner side surface 4F. As shown in FIG. 1, on the top surface 4A, the conducting wire 6 and the conducting wire 7 are connected to the terminal electrode 8A and the terminal electrode 9A by thermocompression bonding, respectively. Similarly, the lead wire 6 and the lead wire 7 are connected to the terminal electrode 8B and the terminal electrode 9B by thermocompression bonding on the top surface 5A.

  Hereinafter, the manufacturing method about the coil component 1 of the said structure is demonstrated. First, as shown in FIG. 3, the terminal electrode 8A, the terminal electrode 9A, the terminal electrode 8B, and the terminal electrode 9B are formed on the flange 4 and the flange 5 of the magnetic core 2 by plating.

  Next, an insulation covered electric wire manufacturing process is performed. In the insulated coated electric wire manufacturing process, in order to obtain the above-described composite resin, a predetermined epoxy resin, a silicone resin, and an epoxy resin curing agent are mixed in a predetermined ratio, and a solvent is appropriately used to obtain a predetermined viscosity. This is heated to a predetermined temperature for a predetermined time, and a silicone resin is reacted with the epoxy resin to produce a silicone-modified epoxy resin. The produced resin is a composite resin in which the silicone modification rate of the epoxy resin is 5 to 30%. The obtained composite resin is dissolved in a solvent as necessary to obtain a varnish having a predetermined viscosity.

  Next, the varnish is attached to the wire through the conductor 6, the conductor (not shown) of the conductor 7, and the wire used as the conductor 7 </ b> A in the container in which the obtained varnish is stored. After deposition, the varnish is heated to volatilize the solvent and initiate the curing reaction. The curing reaction is stopped halfway by controlling the heating temperature and heating time, and the epoxy resin is brought into a semi-cured state.

  The wire is delivered from the delivery reel, dipped in the varnish and coated with an insulating coating, and then taken up on the take-up reel and pulled up from the varnish. Heating is performed during the pulling process. The heating is performed, for example, by heating at about 80 ° C. for about 30 minutes in a heat treatment furnace or the like. This heating is the first heat treatment step, and the conductor 6 and the coating 7B (not shown) of the conductor 7 are in a semi-cured state by the first heat treatment step.

  A semi-cured state is achieved by appropriately controlling the wire pulling speed, heating temperature, and the like. In addition, methods such as hot air heating heaters, lamps, radiant heating by laser, heating by energization heating of the core wire, high frequency induction heating, etc. can be employed. The above is the insulation coated electric wire manufacturing process.

  Next, the conducting wire 6 and the conducting wire 7 are made substantially parallel and wound along the corners formed by the top surface 3A, the side surface 3B, the bottom surface 3C, the side surface 3D, and the respective surfaces of the core portion 3 ( 3 and 4). The conducting wire 6 and the conducting wire 7 are wound around the core portion 3 and one end side of the conducting wire 6 and the conducting wire 7 is wired along the inner side surface 4F of the flange portion 4, and then one end of the conducting wire 6 is formed on the top surface 4A. The one end of the conducting wire 7 is disposed on the terminal electrode 9A formed on the top surface 4A (FIG. 4). Similarly, the other ends of the conducting wire 6 and the conducting wire 7 are disposed on the terminal electrode 8B and the terminal electrode 9B on the top surface 5A, respectively (FIG. 4).

    After arrange | positioning the conducting wire 6 and the conducting wire 7 on the terminal electrode 8A and the terminal electrode 9A, respectively, the crimping element which is not illustrated is pressed on the terminal electrode 8A and the terminal electrode 9A, and 300 to 400 degreeC heat is applied, and the conducting wire 6 and the conducting wire are applied. 7 is thermocompression-bonded and connected. When the above connecting process is completed, the coil component 1 is temporarily shaped as a complete body (FIG. 1).

  However, the coating 6B and the coating 7B at the core portion are still in a semi-cured state. There are parts that are inferior in high temperature durability. Therefore, as a second heat treatment step, the entire coil component 1 including the conductor 6 and the conductor 7 is heated and cured at about 180 ° C. for about 40 minutes. As a result, the coating 6B and the coating 7B are in a fully cured state, the resin is completely cured and exhibits performance as a protective coating, and has a high melting point and excellent heat resistance.

  Next, a test for manufacturing the common mode choke coil according to the above-described embodiment and confirming the effect was performed. About the covering of the conducting wire of the common mode choke coil used for the test, it is as follows.

As the epoxy resin, a bisphenol A type epoxy resin having an average molecular weight of about 900 is used. For example, shrimp coat 1001 manufactured by Japan Epoxy Resin Co., Ltd. represented by the following chemical formula 1 is used.

Moreover, as a silicone resin, Chisso Corporation FM-311 (average molecular weight 1000) shown by following Chemical formula 2 is used, for example.

As the epoxy resin curing material, a formaldehyde condensation-based acetylated modified product is used. For example, Ebicure DC808 manufactured by Japan Epoxy Resin Co., Ltd. represented by the following chemical formula 3 is used.

  When the epoxy resin, silicone resin and curing agent are mixed and heated at 80 ° C. for 3 hours to perform the first heat treatment step, the silicone resin reacts with the epoxy resin to produce a silicone-modified epoxy resin. A resin is obtained. And a varnish is obtained by using toluene as a solvent and setting it as an appropriate viscosity. An example of the use ratio (% by weight) of the material until the varnish is obtained is as follows: bisphenol A type epoxy resin 35.7%, silicone resin 8.9%, acetylated modified product (curing agent) 5.4%, solvent (Toluene) 50%.

  The varnish thus prepared was applied to the wire body as described above and heated at a temperature of 200 to 290 ° C. for 5 to 20 seconds. By this heating, the solvent was volatilized and the epoxy resins (unmodified epoxy resin and silicone-modified epoxy resin) were in a semi-cured state. In this way, an insulating coating having a thickness of 5 μm was formed on a wire material which is a bare copper wire having a diameter of 70 μm. The dielectric constant of this insulating coating is about 2.6. The common mode choke coil (product of the present invention) of the above-described embodiment for use in the test was manufactured using the conductive wire thus manufactured.

  Further, as a comparison material, a child (a comparative product) in which a child-mode choke coil was manufactured using a conductive wire coated with an insulating material of polyurethane resin was used. The dielectric constant of this insulating coating is about 3.5 to 4.0.

In the test, the common mode choke coil manufactured as described above was used to measure the capacitance between the conductors when the resonance frequency was 100 MHz and the cut-off frequency when attenuated by 3 dB. The results are as shown in the graphs of FIGS. 5 and 6 and Table 1. In FIG. 5, the graph having a lower capacitance (pF) value at each frequency is the product of the present invention, and the graph having a higher capacitance value is the comparison product. In FIG. 6, the graph having a higher overall frequency value for each attenuation (dB) is the product of the present invention, and the graph having a smaller frequency value is the comparative product.

  As shown in the graph of FIG. 5, the capacitance Cp between the conductors is smaller in the product of the present invention than in the comparative product, and the result is generally good. Focusing on the resonance frequency of 100 MHz, as shown in Table 1, the comparative product has a large value of 1.94 pF, while the present product has a small value of 1.52 pF. For this reason, even if the space | interval of conducting wire has dispersion | variation, it turns out that the dispersion | variation in the capacity | capacitance Cp between conducting wires can be suppressed small.

  Further, as shown in the graph of FIG. 6 and Table 1, the cutoff frequency when attenuated by 3 dB is a low value of 1.44 GHz in the comparative product, whereas 1.85 GHz in the product of the present invention. It is a high value. Therefore, it can be seen that the resonance frequency is high and the high frequency characteristics are good.

  As a modification of the first embodiment described above, as shown in FIG. 7, a plate core 10 may be attached across the flange 4 and the flange 5 at both ends of the coil component 1. By adopting this form, it is possible to increase the inductance value of the entire coil component. The plate-shaped core 10 is joined to the collar part 4 and the collar part 5 with an adhesive. A thermosetting adhesive is used as this adhesive.

  Specifically, after connecting the conducting wire 6 and the conducting wire 7, the plate-like core 10 is temporarily bonded to the flange portion 4 and the flange portion 5 with an adhesive. The coil component 1 enters the second heat treatment step after the connection. At this time, the plate core 10 is also heated at the same time, and the adhesive between the plate core 10 and the flange portion 4 and the flange portion 5 is cured. The plate core 10 is integrated with the coil component 1. That is, in the modified example of the first embodiment, it is possible to join the plate cores 10 at the same time by the second heat treatment step without particularly providing a step of joining the plate cores 10, and in particular, man-hours. It is possible to increase the performance of the entire coil component without increasing the value.

  In the first embodiment, a ferrite core is used as the magnetic core 2. However, the present invention is not limited to this. For example, a ceramic core may be used as long as it is a coil component that requires high-frequency characteristics.

  Next, as a second embodiment, a coil component using laser welding at the time of connection will be described with reference to FIGS. The coil component 11 shown in FIG. 10 takes substantially the same form as the coil component 1 according to the first embodiment, and as shown in FIG. 8, the winding core portion 13 and the flange portions 14 provided at both ends thereof, A metal terminal 18, which is a terminal electrode, is provided on the core 12 composed of the flange portion 15. And as shown in FIG. 11, the conducting wire 16 and the conducting wire 17 which were wound around the core part 13 (FIG. 8) are welded and connected to the metal terminal 18, respectively. The conducting wire 16 and the conducting wire 17 are covered conducting wires coated with a mixed resin containing a silicone-modified epoxy resin, as in the first embodiment.

  As shown in FIG. 8, the flange portion 14 has a top surface 14A, a bottom surface 14C, and an inner side surface 14F that is a connection surface with the core portion 13 and a front side surface 14E that faces the inner side surface 14F, as in the first embodiment. , And the side surface 14B and the side surface 14D, and the flange portion 15 is configured in the same manner. As shown in FIG. 9, a step portion 14 f (FIG. 9) in which the axial thickness of the core portion 13 is thin is formed at the end portions of the inner side surface 14 </ b> F on the side surface 14 </ b> B side and the side surface 14 </ b> D side. Has been.

  Moreover, the recessed part 19 formed with the groove | channel connected from the top surface 14A of the collar part 14 to the lower surface 14C is each formed in the both ends of the front side surface 14E of the collar part 14 as a retaining part which prevents the metal terminal from detaching ( FIG. 9). The recess 19 is also formed on the side surface 15E of the flange portion 15 in the same manner. The coil component 11 has a length of 4.5 mm, a width of 3.2 mm, and a height of 2 mm.

  The metal terminal 18 serving as a terminal electrode is a copper alloy such as phosphor bronze or brass, and is bent into a substantially U shape. As shown in FIG. 9, the side surface portion 18A, the top surface portion 18B, the bottom surface portion 18C, It has upper and lower folded portions 18D. Further, a convex portion 18E that protrudes toward the inner surface side is formed on the inner surface of the side surface portion 18A as a metal fitting-side retaining portion that engages with the core-side retaining portion 19. Further, the upper surface portion 18B is integrally formed with a connecting portion 20 formed of an inverted L-shaped bent portion.

  The connecting portion 20 is open toward the distal end of the flange portion 14 for the convenience of inserting the conducting wire 16 and the conducting wire 17. The connecting portion 20 may be opened in the direction opposite to the distal end direction. Such a metal terminal 18 is inserted into the flange 14 from the side surface 14B and side surface 14D, which are the sides thereof, and is fitted and mounted (FIG. 9).

  In this case, the convex part 18E as the metal part side retaining part fits into the concave part 19 as the core side retaining part, and the folded part 18D presses the step part 21 so that the metal terminal as shown in FIG. 18 is attached to the collar 14. By forming the step portion 21 on the flange portion 14, the folded portion 18 </ b> D is prevented from projecting to the core portion 13 so that the winding work around the core portion 13 is not hindered.

  Hereinafter, the manufacturing method about the coil component 11 of the said structure is demonstrated. First, as shown in FIGS. 8 and 9, metal terminals 18 to be terminal electrodes are attached to the flange portions 14 and 15 of the core 12. When the metal terminal 18 is attached, no adhesive is used because the retaining portion is formed on the core side and the metal fitting side, and the metal terminal 18 is fitted to the flange portion 14 and the flange portion by fitting the protrusion 18E and the recess 19 together. 15 is fixed.

  Next, the conducting wire 16 and the conducting wire 17 are wound around the core part 13 of the core 12 (FIG. 10). At this time, the conducting wire 16 and the conducting wire 17 are preheated for about 30 minutes at about 80 ° C. in a heat treatment furnace or the like as the first heat treatment step in the same manner as in the first embodiment, and the coating becomes semi-cured. Yes. Since the winding process is the same as that of the first embodiment, the details are omitted.

  After the conducting wire 16 and the conducting wire 17 are wound around the winding core portion 13, one end side of the conducting wire 16 and the conducting wire 17 is wired along the inner side surface 14 </ b> F and the top surface 14 </ b> A of the flange portion 14, and one end thereof is connected to the metal terminal 18. The unit 20 is disposed. Then, by caulking the connecting portion 20, the conducting wire 16 and the conducting wire 17 are fixed to the metal terminal 18, respectively. Thereafter, the connecting portion 20, the conducting wire 16 and the conducting wire 17 are melted by laser welding or arc welding, and the conducting wire 16, the conducting wire 17 and the metal terminal 18 are integrated electrically and mechanically.

  At this time, welding with a laser beam is performed, and the conductors 16 and 17 are melted. Since the coating of the conducting wires 16 and 17 is in a semi-cured state, the melting point is low, and the coating of the conducting wires 16 and 17 can be dissolved without carbonizing the coating by the heat of the laser beam. Furthermore, the conducting wire 16 and the conducting wire 17 are fixed at the connecting portion 20, so that the conducting wire 16 and the conducting wire 17 are not disturbed by the impact of the laser beam at the time of welding and can be suitably welded without causing a positional shift or the like. .

  Similarly, the lead wire 16 and the lead wire 17 are connected to the metal terminal 18 in the flange portion 15, and the coil component 11 is shaped as shown in FIG. Thereafter, as in the first embodiment, as a second heat treatment step, the entire coil component 11 including the conductor 16 and the conductor 17 is heated and cured at about 180 ° C. for about 40 minutes, and the coating is made into a fully cured state. 11 is completed.

  In the first embodiment, the connection is performed by thermocompression bonding, but as shown in the second embodiment, when performing the connection using a laser, by making the coating semi-cured, It becomes possible to connect suitably without carrying out peeling processing of a coating.

  Next, as a third embodiment, a coil component using a drum core and molded with a mold resin will be described with reference to FIGS. As shown in FIG. 16, the coil component 31 according to the third embodiment is formed in a substantially rectangular parallelepiped shape by a mold resin 44, and lead terminals 42 serving as terminal electrodes at the time of circuit mounting at both ends of the rectangular parallelepiped. , 43 are arranged.

  As shown in FIG. 12, the core 32 constituting the coil component 31 is configured by providing substantially disk-shaped flange portions 34 and flange portions 35 at both ends of a substantially cylindrical core portion 33. Electrodes 34A and 34B are formed by plating or sputtering on the opposite surface of the flange portion 34 to the surface to be joined to the core portion 33, and the same electrode portion is also formed on the flange portion 35. As shown in FIGS. 13 and 14, the lead terminals 42 and 43 electrically connected to the electrode portions 34 </ b> A and 34 </ b> B are partially extended from the lead frame 41 that supports the core 32 and the like when the coil component 31 is manufactured. The tip is bent at a substantially right angle to form core holding portions 42A and 43A.

  As shown in FIGS. 13 and 14, the conductive wires 36 and 37 that are alternately wound around the core portion 33 are covered with a composite resin containing a silicone-modified epoxy resin, as in the first embodiment. The lead wire is wired from the winding core portion 33 to the electrode portions 34A and 34B where the lead terminals 42 and 43 abut along the outer periphery of the flange portion 34. Similarly, the lead wire 36 is also wired to the electrode portion of the flange portion 35.

  Hereinafter, the manufacturing method about the coil component 31 of the said structure is demonstrated. First, as shown in FIG. 12, the electrode portions 34 </ b> A and 34 </ b> B are formed on the flange portion 34 of the core 32, and the same electrode portion is formed on the flange portion 35. Thereafter, the conductive wires 36 and 37 heat-treated in the first heat treatment step are wound around the core portion 33. The core portion 33 according to the third embodiment has a cylindrical shape, and the coating of the conductors 36 and 37 is also preheated in a heat treatment furnace or the like at about 80 ° C. for about 30 minutes by the first heat treatment step, and is semi-cured. Since it is in a state and is in a state of being flexible, it can be wound without stress when the conducting wires 36 and 37 are wound.

  After the conducting wires 36 and 37 are wound around the core portion 33, one end side of each of the conducting wires 36 and 37 is wired along the flange portion 34 to the electrode portions 34 </ b> A and 34 </ b> B, and the other end side is similarly extended along the flange portion 35. Wiring is performed up to the electrode portion of the flange portion 35. The lead frame 41 is preliminarily cut into a substantially H shape by pressing or the like, and the projecting piece portions at both ends of the lead frame 41 cut into a substantially H shape become lead terminals 42 and 43, and the tips thereof are bent to form the core 32. The core holding portions 42A and 43A to be held are used.

  The core 32 around which the conducting wires 36 and 37 are wound is disposed and held between the core holding portions 42A and 43A and the core holding portions 42A and 43A. At this time, one ends of the conductive wires 36 and 37 wired on the side of the flange 34 are arranged between the core holding part 42A and the electrode part 34A, and between the core holding part 43A and the electrode part 34B, respectively. The other ends of the conductive wires 36 and 37 wired on the 35 side are respectively disposed between the core holding portions 42A and 43A and the electrode portion on the flange 35 side (FIG. 14).

  Thereafter, the core holding part 42A and the conductor 36 are soldered, and the core holder 43A and the conductor 37 are soldered (FIG. 15). At this time, since the coating of the conductors 36 and 37 is melted by the heat of soldering and the conductor portion is exposed, it is possible to perform soldering without performing a coating peeling process. In this soldering, the core holding portions 42A and 43A and the conductive wires 36 and 37 are soldered, respectively, and the core holding portion 42A and the electrode portion 34A are soldered, and the core holding portion 43A and the electrode are soldered. The part 34B is soldered. The electrode portion formed on the flange portion 35 and the conductive wires 36 and 37 are also soldered in the same manner.

  After the core 32 and the conductors 36 and 37 are soldered to the lead frame 41, as a second heat treatment step, the conductors 36 and 37 are integrally heated with the lead frame 41 and the core 32 at about 180 ° C. for about 40 minutes. , 37 is in a fully cured state. Thereafter, the unit including the core 32, the conductive wires 36 and 37, and the lead terminals 42 and 43 is covered with the mold resin 44 (FIG. 16). Also in this case, the conducting wires 36 and 37 are covered with the fully cured coating.

  Further, since the core 32 and the like are integrally covered with the mold resin 44, the protection performance against external causes as the coil component 31 as a whole is increased, and the coil component having a more stable operation can be obtained. After the core 32 is covered with the mold resin 43 and molded into a substantially rectangular shape, the lead terminals 42 and 43 are cut off from the lead frame 41, and the cut off tip portions are processed. As shown in FIG. 31 is completed.

  Next, a coil component having a shape in which a substantially circular toroidal core is built in a resin case will be described as a fourth embodiment with reference to FIGS. As shown in FIG. 17, the coil component 51 shown in FIG. 20 has a substantially annular toroidal core 52 inserted in a resin case 53. The toroidal core 52 is wound by bifilar winding in which two conductors 56 and 57 are wound in parallel at the same time. As shown in FIG. 18, one end and the other end of the conductors 56 and 57 are wound. Are extended substantially radially in the four directions of the toroidal core 52. The conducting wire 56 and the conducting wire 57 are coated conducting wires coated with a composite resin containing a silicone-modified epoxy resin, as in the first embodiment.

  As shown in FIG. 17, the resin case 53 has a plate-like base 54 having a substantially square shape and a substantially circular opening formed at the center thereof, and extends from the opening edge of the base 54 to one surface in the normal direction of the base 54. It is comprised from the cylindrical part 55 comprised from the substantially cylindrical wall and the cover which covers one of the walls. The toroidal core 52 is inserted and held from the other surface side of the base 54 in a space formed in the cylindrical portion 55.

  At the four corners of the base 54, holes 54a penetrating from the other surface side of the base 54 to the one surface side are formed, and substantially L-shaped metal terminals 58 serving as terminal electrodes are formed in the holes 54a from the other surface of the base 54. It is inserted toward one surface, and the inserted tip portion projects from one surface of the base 54 to form a connecting portion 58A (FIG. 19). Moreover, the part located in the other surface side of the metal terminal 58 becomes a part joined to the circuit when the coil component 51 is mounted on the circuit.

  In the vicinity of the holes 54a formed at the four corners of the side surface of the base 54, as shown in FIG. In the groove 54 b, one end side and the other end side of the conducting wire 56 and the conducting wire 57 are connected to a connecting portion 58 A provided on one surface side of the base 54 with the toroidal core 52 inserted into the resin case 53. Therefore, it becomes a place to be wired (FIG. 19).

  Hereinafter, the manufacturing method about the coil component 51 of the said structure is demonstrated. First, the conducting wire 56 and the conducting wire 57 are wound around the toroidal core 52 by bifilar winding. At this time, the conducting wire 56 and the conducting wire 57 are preliminarily heat-treated at about 80 ° C. for about 30 minutes by a heat treatment furnace or the like as a first heat treatment step, and the coating is in a semi-cured state.

  Next, after the conducting wire 56 and the conducting wire 57 are wound around the toroidal core 52, one end side and the other end side thereof are extended toward substantially four directions of the toroidal core 52. In this state, as shown in FIG. 17, the toroidal core 52 is inserted into the cylindrical portion 55 of the resin case 53 through the opening formed in the base 54 of the resin case 53. At this time, the metal terminals 58 are inserted into the holes 54 a formed at the four corners of the base 54.

  After the toroidal core 52 is inserted into the cylindrical portion 55, one end side and the other end side of the conducting wire 56 and the conducting wire 57 are routed through the groove 54b to the other surface side of the base 54 (FIGS. 18 and 19). Then, as shown in FIG. 19, the wire is wound around the connecting portion 58A protruding from the base 54. It is not necessary to remove the coating from the portion wound at this time.

  After the conducting wire 56 and the conducting wire 57 are wound around the joining portion 58A, as shown in FIG. 20, the joining is performed by soldering or welding. At this time, since the coating of the conducting wire 56 and the conducting wire 57 is in a semi-cured state, the melting point is low, and it is melted by the heat at the time of connection. After the connection of the conducting wire 56 and the conducting wire 57 is finished, as a second heat treatment step, the conducting wire 56 and the conducting wire 57 are heated together with the resin case 53 and the toroidal core 52 at about 180 ° C. for about 40 minutes. The coil component 51 is completed by setting the coating of 57 to the fully cured state and improving the heat resistance and strength characteristics of the coating.

  Next, a coil component according to a fifth embodiment will be described with reference to FIG. The coil component 60 according to the fifth embodiment includes a coil body composed of a drum type core 61 around which conductive wires 63 and 64 are wound, and a ring core 62 having a coil body housing portion 62A for housing the coil body. A concave part 62a having a substantially cylindrical shape is formed in the coil main body accommodating part 62A, and the coil main body is coaxially disposed and accommodated in the concave part 62a.

  The ring core 62 includes metal terminals 65 to 68 serving as four terminal electrodes, and one end and the other end of the conductive wires 63 and 64 wound around a winding core (not shown) of the drum type core 61 are four terminals. One to each of the metal terminals 65 to 68 serving as electrodes. The covering of the conducting wires 63 and 64 is made of a composite resin containing a silicone-modified epoxy resin, similarly to the covering of the conducting wires according to the above-described embodiment.

  In the manufacturing method of the coil component 60, the drum type core 61 in which the conducting wires 63 and 64 are wound is accommodated in the recess 62a of the coil main body accommodating portion 62A, and one end and the other end of the conducting wires 63 and 64 have four terminals. After being connected one by one to the metal terminals 65 to 68 to be electrodes, the coil main body composed of the drum type core 61 around which the conductive wires 63 and 64 are wound and the ring core 62 are integrated. Heated at 180 ° C. for about 40 minutes. As a result, the coating of the conductive wires 63 and 64 is made into a fully-cured state, the heat resistance and strength characteristics of the coating are improved, and the coil component 60 is completed.

  In the first heat treatment step in the above-described embodiment, the heat treatment is performed at about 80 ° C. for about 30 minutes. However, the heat treatment is not limited to this. For example, the heat treatment may be performed at about 500 ° C. for about 5 seconds. In the second heat treatment step, the heat treatment is performed at about 180 ° C. for about 40 minutes. However, the heat treatment is not limited to this. For example, the heat treatment may be performed at 150 ° C. to 200 ° C. for about 10 minutes to 120 minutes.

  Moreover, in the above-mentioned form, the coating of the conductive wire containing the silicone-modified epoxy resin is in a semi-cured state and is wound before the conductive wire is wound around the magnetic core or the like constituting the common mode choke coil. However, it may be in the fully cured state before the conducting wire is wound around the magnetic core or the like.

  The common mode choke coil of the present invention is particularly useful in a field where a high cut-off frequency is required.

The perspective view which shows the completion state of the coil components which concern on 1st embodiment of this invention. The block diagram of the conducting wire of the coil components which concern on 1st embodiment of this invention. The perspective view which shows the core and terminal electrode of a coil component which concern on 1st embodiment of this invention. The perspective view which shows the connecting wire front body of the coil components which concern on 1st embodiment of this invention. The graph which shows the test result about the capacity | capacitance between the conducting wires of the common mode choke coil which concerns on 1st embodiment of this invention. The graph which shows the test result about the cut-off frequency of the common mode choke coil which concerns on 1st embodiment of this invention. The perspective view of the state which provided the plate-shaped core of the coil components which concern on 1st embodiment of this invention. The perspective view of the core and metal terminal of the coil component which concern on 2nd embodiment of this invention. The detailed perspective view which showed the direction which attaches the metal terminal of the coil components which concern on 2nd embodiment of this invention. The perspective view which shows the connecting wire front body of the coil components which concern on 2nd embodiment of this invention. The perspective view which shows the completion state of the coil component which concerns on 2nd embodiment of this invention. The perspective view which shows the core and electrode part of the coil component which concern on 3rd embodiment of this invention. The perspective view which shows the state by which winding was performed to the core of the coil components which concern on 3rd embodiment of this invention. The perspective view which shows the state by which the core was hold | maintained at the lead frame of the coil components which concern on 3rd embodiment of this invention. The perspective view which shows the state by which the connection of the coil components which concern on 3rd embodiment of this invention was performed. The perspective view which shows the completion state of the coil component which concerns on 3rd embodiment of this invention. The perspective view which shows the positional relationship of the corner | angular component of the coil components which concern on 4th embodiment of this invention. The lower surface side top view of the coil component which concerns on 4th embodiment of this invention. The perspective view which shows the state before the connection of the coil components which concern on 4th embodiment of this invention. The perspective view which shows the completion state of the coil component which concerns on 4th embodiment of this invention. The perspective view which shows the completion state of the coil component which concerns on 5th embodiment of this invention.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Coil component 2 Magnetic core 3 Winding core part 4 Collar part 5 Collar part 6 Conductor 6B Covering 7 Conductor 7A Conductor 7B Covering 8A Terminal electrode 8B Terminal electrode 9A Terminal electrode 9B Terminal electrode 10 Plate-shaped core 11 Coil part 12 Core 13 Core Part 14 collar part 15 collar part 16 conducting wire 17 conducting wire 18 metal terminal 18A side surface part 18B top surface part 18C bottom surface part 18D folded part 18E convex part 19 concave part 20 connecting part 21 step part 31 coil part 32 core 33 winding core part 34 collar part 34A electrode part 34B electrode part 35 collar part 36 conducting wire 36 coating 41 lead frame 42 lead terminal 42A core holding part 43 lead terminal 43A core holding part 44 mold resin 51 coil Product 52 Toroidal core 53 Resin case 54 Base 54a Hole 54b Groove 55 Cylindrical part 56 Conductor 57 Conductor 58 Metal terminal 58A Connection part 60 Common mode choke coil 61 Drum type core 62 Ring core 63 Conductor 64 Conductor 65 Metal terminal 66 Metal terminal 67 Metal Terminal 68 Metal terminal

Claims (4)

The core,
A coated conductor wound around the core with an insulation coating;
A terminal electrode having a connecting portion and a user terminal connected to the coated conducting wire;
The common mode choke coil, wherein the insulating coating has a modified epoxy resin and a relative dielectric constant of 2.0 to 3.0.   The insulating coating is composed of a composite resin of an epoxy resin, a silicone resin, and an epoxy resin curing agent, and the modified epoxy resin is a silicone-modified epoxy resin obtained by modifying the epoxy resin with the silicone resin. The common mode choke coil according to claim 1.   In the composite resin, when the chemical equivalent of the epoxy resin obtained by dividing the average molecular weight by the functional group is x and the chemical equivalent of the silicone resin is y, the weight ratio of the epoxy resin to the silicone resin is x / y. 3. The common mode choke coil according to claim 2, wherein the common mode choke coil is mixed at a value exceeding.   The common mode choke coil according to claim 2 or 3, wherein a silicone modification ratio of the epoxy resin in the composite resin is in the range of 5 to 30%.

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