JP2022143320A - choke coil - Google Patents

Abstract

To provide a choke coil that can be made smaller, higher output, and higher performance than before.SOLUTION: A choke coil includes two winding shafts 1, 1C, 2, and 2C around which coils CL11 and CL12 are respectively wound via bobbins B11 and B12, two common shafts 3 and 3C and common shaft 4 and common shaft 4C, and connecting portion 5 and connecting portion 5C, and further includes two cores C11 and C12 used facing each other, bobbin B11 and bobbin B12, and coil CL11 and coil CL12, and a gap G3 and a gap G4 having a length corresponding to the value of the normal mode inductance to be provided as the choke coil CK1 are provided between the common shaft 3 and the common shaft 3C and between the common shaft 4 and the common shaft 4C.SELECTED DRAWING: Figure 1

Description

The present invention belongs to the technical field of choke coils.

A choke coil as an electronic component is widely used in various devices. A noise filter including such a choke coil is disclosed, for example, in Patent Document 1 below. A noise filter disclosed in Patent Document 1 listed below includes a magnetic core, a ground conductor, and two coils. Each coil has a coil portion wound around a magnetic core and two terminals drawn out from the coil portion. The ground conductor has a conductor main portion spaced apart from the coil portion and a ground terminal drawn out from the conductor main portion. The circuit board is provided with four electrodes each connected to two terminals and a ground electrode connected to a ground terminal. Then, Cp+Cw, which is the combined capacitance of the pattern capacitance Cp between the electrodes and the winding capacitance Cw of the coil, is 0.29×Cg−3. 06 or more and 0.29×Cg+2.15 or less.

Japanese Patent Application Laid-Open No. 2020-9900 (Fig. 2, etc.)

However, in view of the recent demand for improvements in miniaturization, high output, high performance, etc. for electronic components, further miniaturization, high output, and high performance compared to the choke coil disclosed in Patent Document 1 is desired.

SUMMARY OF THE INVENTION Accordingly, the present invention has been made in view of the above requirements, and one of the objects thereof is to provide a choke coil that can be made smaller in size, higher in output, and higher in performance than conventional ones.

In order to solve the above problems, the invention according to claim 1 provides two first shafts each having a coil wound thereon via an insulating bobbin, the first shafts being parallel to each other and each having a columnar shape. and two second shafts parallel to each other and each being columnar, the second shafts parallel to the first shafts, the ends of the first shafts, and the ends of the first shafts a plate-like connection portion connecting the end portions of each of the second shafts corresponding to and through the first shaft and the second shaft, the magnetic flux generated by the current flowing in each of the coils passing through the first shaft and the second shaft two cores used facing each other; two bobbins through which the respective first shafts are passed inside and the coils are wound outside; and the coils wound around the first axis via the coils, and the ends of the cores opposite to the connection part on the second axis of the cores are connected to each other by choke coils. are separated by a length corresponding to the value of the normal mode inductance to be provided.

According to the first aspect of the invention, the end portions of each core opposite to the connecting portion on the second axis and facing each other correspond to the value of the normal mode inductance to be provided as the choke coil. separated by a length. Therefore, since one choke coil can generate both normal mode inductance and common mode inductance, the size of the choke coil that can generate inductance in each mode can be reduced. Therefore, for example, it is possible to achieve miniaturization, high output, and high performance as a noise filter.

In order to solve the above problems, the invention according to claim 2 provides two first shafts each having a coil wound thereon via an insulating bobbin, the first shafts being parallel to each other and each having a columnar shape. and two second shafts parallel to each other and each being columnar, the second shafts parallel to the first shafts, the ends of the first shafts, and the ends of the first shafts a plate-like connection portion connecting the end portions of each of the second shafts corresponding to and through the first shaft and the second shaft, the magnetic flux generated by the current flowing in each of the coils passing through the first shaft and the second shaft two cores each provided with a connecting portion for, two said bobbins through which each said first shaft is passed inside and said coils are wound outside, said first shaft via said bobbins the coils respectively wound on the coils, wherein the connecting part is made of a ferrite material, the first shaft is made of a dust-based material, and the second shaft is either the ferrite material or the dust-based material is configured to consist of

According to the invention of claim 2, in the choke coil having the core including the first shaft, the second shaft, and the connection portion, the connection portion is made of a ferrite material, and the first shaft is a dust-based choke coil. Since the second shaft is made of either a ferrite material or a dust-based material, it is possible to increase the current as a choke coil by improving the DC superimposition characteristics. Therefore, for example, miniaturization as a transformer, high output capability, and high performance are possible.

In order to solve the above-mentioned problems, the invention according to claim 3 provides the choke coil according to claim 2, wherein the relationship between the magnetic permeability μ1 of the ferrite material and the magnetic permeability μ2 of the dust material is μ1 : μ2=100:1.

According to the invention of claim 3, in addition to the effects of the invention of claim 2, since the relationship between the magnetic permeability of the ferrite material and the magnetic permeability of the dust material is 100:1, it can be used as a choke coil. can further improve the DC superimposition characteristics of

In order to solve the above problems, the invention according to claim 4 provides the choke coil according to claim 2 or claim 3, wherein a volume v1 of one of the first axes constituting one of the cores, The relationship between the total volume v2 obtained by combining the volumes of the two second axes constituting the core and the volume v3 of the connecting portion constituting the core is v1:v2:v3=1:1.3 or more 1.4 or less: Configured to be 2.6 or more and 2.8 or less.

According to the invention described in claim 4, in addition to the effects of the invention described in claim 2 or 3, the volume of one first axis that constitutes one core and the volume of two axes that constitute the core Since the relationship between the total volume including the volume of the second axis and the volume of the connecting portion constituting the core is 1:1.3 or more and 1.4 or less:2.6 or more and 2.8 or less, DC superimposition characteristics as a choke coil can be further improved.

In order to solve the above problems, the invention according to claim 5 provides the choke coil according to any one of claims 1 to 4, wherein the bobbin is a body portion around which the coil is wound. and flanges at both ends of the body that define the range of the body around which the coil is wound, one of the flanges and the body is integrally formed, and the other flange is the A structure is provided that is connected to the body after winding the coil on the body.

According to the invention of claim 5, in addition to the effects of the invention of any one of claims 1 to 4, one flange constituting the bobbin and the body of the bobbin are integrally formed. , and has a structure in which another flange is connected to the body after the coil is wound on the body, so that the coil can be easily wound on the bobbin regardless of whether the cross section of the winding is circular or square. can be turned.

In order to solve the above problems, the invention according to claim 6 provides the choke coil according to any one of claims 1 to 4, wherein the bobbin is a body portion around which the coil is wound. , flanges at both ends of the body portion defining the range around which the coil is wound, a first external terminal portion to which a winding wire having a circular cross section is attached, and a second external terminal portion to which a winding wire having a square cross section is attached. A second external terminal portion, which is an external terminal portion, is provided in parallel with the first external terminal portion.

According to the invention of claim 6, in addition to the effect of the invention of any one of claims 1 to 4, the second external terminal part is provided in parallel with the first external terminal part. Therefore, it is possible to reduce costs by standardizing parts for windings having different cross-sectional shapes.

According to one aspect of the present invention, the end portions of the two cores opposite to the connecting portion on the second axis and facing each other correspond to the value of the normal mode inductance to be provided as the choke coil. separated by a length.

Therefore, since one choke coil can generate both normal mode inductance and common mode inductance, the size of the choke coil that can generate inductance in each mode can be reduced.

According to another aspect of the present invention, in a choke coil having a core including a first shaft, a second shaft, and a connection portion, the connection portion is made of a ferrite material, and the first shaft is made of dust. The second shaft is made of either a ferrite material or a dust material.

Therefore, it is possible to increase the current of the choke coil by improving the DC superimposition characteristics.

1 is an external perspective view showing the structure of a choke coil of a first embodiment, where (a) is an external perspective view showing the structure of a core used in the choke coil, and (b) is the structure of the entire choke coil; It is an external perspective view showing the. 1 is an external perspective view showing the structure of a bobbin used in the choke coil of the first embodiment, where (a) is an external upper perspective view showing the structure of one bobbin, and (b) is the structure of one bobbin; It is an external downward perspective view showing the. 1 is an external perspective exploded view showing the structure of a choke coil according to a first embodiment; FIG. FIG. 4A is an external perspective view showing the structure of the choke coil as a whole, and FIG. 4B is an exploded view showing the structure of the choke coil. FIG. 8 is a diagram showing the structure of a bobbin used in the choke coil of the second embodiment, where (a) is an external perspective view showing the structure when a set of bobbins are combined, and (b) is one bobbin; 1 is an external upper perspective view showing the structure of 1, and (b) is an external lower perspective view showing the structure of one bobbin. It is a diagram showing the respective effects of the choke coil of the first embodiment and the choke coil of the second embodiment, (a) is an equivalent circuit of a conventional choke coil, (b) is the choke coil of the first embodiment and FIG. 10C is an equivalent circuit of each of the choke coils of the second embodiment, and (c) is a drive current-inductance characteristic diagram of each of the choke coils of the first embodiment and the choke coil of the second embodiment; FIG. 10A is an external perspective view showing the structure of the choke coil as a whole, and FIG. 11B is an exploded view showing the structure of the choke coil according to the third embodiment; FIG. 10A is an external perspective view showing the structure of the choke coil as a whole, and FIG. 10B is an exploded view showing the structure of the choke coil according to the fourth embodiment; FIG. 10 is a drive current-inductance characteristic diagram for each of the choke coil of the third embodiment and the choke coil of the fourth embodiment;

Next, embodiments of the present invention will be described based on the drawings. Each of the embodiments described below applies to noise reduction choke coils (corresponding to the first and second embodiments) or transformer choke coils (corresponding to the third and fourth embodiments). It is an embodiment in the case of applying the present invention to.

(I) First embodiment
First, a choke coil according to a first embodiment of the invention will be described with reference to FIGS. 1 to 3. FIG. 1 is an external perspective view showing the structure of the choke coil of the first embodiment, FIG. 2 is an external perspective view showing the structure of a bobbin used in the choke coil, and FIG. 3 is the structure of the choke coil. 1 is an external perspective exploded view showing the .

As shown in FIGS. 1 to 3, the choke coil CK1 of the first embodiment includes a core C11 whose appearance is shown in FIG. and are combined vertically, for example, so that the end surfaces of the respective shafts are opposed to each other. In the following description, when describing matters common to the core C11 and the core C12 of the first embodiment, these are collectively simply referred to as "core C11 and the like".

Here, the material forming each of the core C11 and the like is selected based on the oscillation frequency of the choke coil CK1 in which the core C11 and the like is used (in other words, the required magnetic permeability of the core C11 and the like) and the manufacturing cost. More specifically, for example, a ferrite material or the like is used.

As shown in an external perspective view of FIG. 1(a), the core C11 of the first embodiment includes a flat top surface 5, columnar winding shafts 1 and 2, and a common shaft 3 and a common shaft. 4 and are integrally formed. On the other hand, the core C12 of the first embodiment also has the same shape as the core C11 and is formed by integral molding. The winding shaft 2C and the common shafts 3C and 4C are integrally formed. 1 and 3, the corresponding shafts of the core C11 and the like (that is, the end surfaces of the winding shafts 1 and 2, the common shafts 3 and 4 shown in FIG. 1, and the core C12). The core C11 and the core C12 are combined vertically, for example, so that the corresponding winding shafts 1C and 2C and the end surfaces of the common shaft 3C and the common shaft 4C are opposed to each other to form the choke of the first embodiment. Used for coil CK1.

In the above configuration, the winding shafts 1 and 2 and the winding shafts 1C and 2C correspond to an example of the "first shaft" of the present invention, and the common shafts 3 and 4 and the common shaft 3C and the common The shaft 4C corresponds to an example of the "second shaft" of the invention of the present application, and the top surface 5 and the top surface 5C correspond to an example of the "connecting portion" of the invention of the present application.

In the core C11 of the first embodiment, the positions of the common axis 3 and the common axis 4 are line-symmetrical positions ( That is, they are formed so as to be separated from the line segment in mutually opposite directions. In other words, as shown in FIGS. 1 to 3, the common shaft 3 and the common shaft 4 and the winding shaft 1 and the winding shaft 2 are cross-shaped in plan view (that is, two-dimensional shape when the top surface 5 is viewed in plan). diagonally across the book). On the other hand, in the core C12 of the first embodiment as well, the positions of the common axis 3C and the common axis 4C are symmetrical with respect to the line segment connecting the central axes of the winding axis 1C and the winding axis 2C. It is formed to be That is, as shown in FIGS. 1 to 3, the common shaft 3C, the common shaft 4C, the winding shaft 1C, and the winding shaft 2C are cruciform in plan view (that is, two winding shafts when the top surface 5C is viewed in plan). diagonally). The positions of the common shaft 3 and the common shaft 4 in the core C11 and the like of the first embodiment are not limited to the positions illustrated in FIGS. 1 to 3 can be wound around the winding shaft 1C and the winding shaft 2C by the required number of turns, the top surface 5 and the top surface 5C have the cross shape in plan view. It can be in any position.

Next, in the core C11 and the core C12 of the first embodiment, when they are opposed to each other and used in the choke coil CK1, as shown in FIG. The length of each of the common shaft 4 and the common shaft 4C is such that a gap G4 is provided between 4T and the end face 4CT opposite to the top face 5C of the common shaft 4C of the core C12 facing the end face 4T. is shorter than the respective lengths of the winding shafts 1 and 1C and the winding shafts 2 and 2C. Similarly, between the end surface 3T of the common axis 3 of the core C11 opposite to the top surface 5 and the end surface 3CT of the common axis 3C of the core C12 opposite to the top surface 5C opposite to the end surface 3T. The lengths of the common shafts 3 and 3C are shorter than the lengths of the winding shafts 1 and 1C and the lengths of the winding shafts 2 and 2C so that the gap G3 is also provided. In the core C11 and the core C12 of the first embodiment, the lengths of the gaps G3 and G4 in the central axis direction of the common axis 4 and the common axis 4C and the common axis 3 and the common axis 3C, respectively (that is, the gap G3 and G4) are set in advance according to the magnitude of the common mode inductance that the choke coil CK1 of the first embodiment should have. The relationship between the length of the gap and the corresponding common mode inductance at this time will be described later with reference to FIG. 6 as experimental results.

On the other hand, the cross-sectional shape of the winding shaft 1 and the winding shaft 2 of the first embodiment is circular, elliptical, or rectangular because the coils are wound as described later. The shape of the cross section of the shaft 3 and the common shaft 4 can be freely changed, for example, to be square or elliptical depending on the installation position, etc., as long as the common shaft 3 and the common shaft 4 are the same. Further, the cross-sectional shape of the winding shaft 1C and the winding shaft 2C of the first embodiment is also circular, elliptical, or rectangular because the coils are wound thereon as will be described later. The shape of the cross section of the shaft 3C and the common shaft 4C can be freely changed, for example, into a square or an elliptical shape depending on the installation position etc., as long as the common shaft 3C and the common shaft 4C are the same.

Next, in the choke coil CK1 of the first embodiment, between the winding shafts 1 and 1C and the coil CL11 wound thereon, and between the winding shafts 2 and 2C and the coil CL12 wound thereon. The structure of the bobbin of the first embodiment inserted between and respectively will be described with reference to FIG.

In the choke coil CK1 of the first embodiment, a bobbin B11 whose structure is illustrated in FIG. 2 and a bobbin B12 having the same shape as the bobbin B11 (see FIGS. 1 and 3) are connected to meshing portions, which will be described later. Used in combination so as to mesh alternately. At this time, the bobbin B11 is inserted between the winding shafts 1 and 1C and the coils wound thereon, and the bobbin B12 is inserted between the winding shafts 2 and 2C and the coils wound thereon. be done. In the following description, when describing matters common to the bobbin B11 and the bobbin B12 of the first embodiment, they are collectively referred to simply as "the bobbin B11 and the like".

As shown in an external perspective view of FIG. 2, the bobbin B11 of the first embodiment has a cylindrical body through which the winding shaft 1 and the winding shaft 1C are passed and a coil CL11 is wound around the outer periphery thereof. 15, a flange 16 and a flange 17 that define a range around which the coil CL11 is wound in the trunk portion 15, a base portion 10, and the above-described engaging portion 11 for engaging the bobbins B11 and B12 so as to face each other. It is integrally formed. As described above, the bobbin B12 of the first embodiment also has the same shape as the bobbin B11 shown in FIG. 2 and is integrally formed. As the material of the bobbin B11 and the like, for example, resin such as plastic is used. 3, the bobbin B11 and the bobbin B12 are combined so that the meshing portion 11 of the bobbin B11 and the meshing portion 11 of the bobbin B12 face each other and mesh with each other. , the winding shaft 1C, the winding shaft 2, and the winding shaft 2C are passed through the first It is used for the choke coil CK1 of the embodiment.

On the other hand, as described above, the cores C11 and C12 of the first embodiment having the above-described structures are the winding axes 1 and 2 and the common axes 3 and 4 of the choke coil CK1 of the first embodiment. The end faces and the end faces of the winding shafts 1C and 2C and the common shafts 3C and 4C are combined so as to face each other. At this time, the end faces of the winding shafts 1 and 2 and the end faces of the winding shafts 1C and 2C are combined so as to abut each other as illustrated in FIG. 1(a). On the other hand, the end face 3T of the common shaft 3 and the end face 3CT of the common shaft 3C, and the end face 4T of the common shaft 4 and the end face 4CT of the common shaft 4C have a gap G3 and a gap G3, respectively, as illustrated in FIG. are combined to form G4 respectively.

The winding shaft 1 and the winding shaft 1C facing each other are inserted into the body portion 15 of the bobbin B11 having the flanges 16 and 17 formed therein. A circular winding W11 is wound by the required number of turns. The winding shaft 2 and the winding shaft 2C, which face each other, are inserted into the body portion 15 of the bobbin B12 similarly formed with the flanges 16 and 17, and the coil CL12 is formed on the outer circumference of the bobbin B12. A winding W12 having a circular cross section is wound by the required number of turns. Copper, for example, is used as the material of these windings W11 and W12. Both ends of the winding W11 toward the outside of the choke coil CK1 are connected to the outside of the choke coil CK1 via an external connection terminal TW11. Both ends of the winding W12 toward the outside of the choke coil CK1 are connected to the outside of the choke coil CK1 via the external connection terminal TW12. For these reasons, a plurality of grooves TG into which the external connection terminals TW11 and TW12 are fitted are formed in the base portion 10 of each of the bobbins B11 and B12. Furthermore, the number of turns of the winding W11 in the coil CL11 and the number of turns of the winding W12 in the coil CL12 are preferably the same.

As described above, in the choke coil CK1 of the first embodiment, the gap G3 is provided between the common shaft 3 and the common shaft 3C, and the gap G4 is provided between the common shaft 4 and the common shaft 4C. It is At this time, in the case where the choke coil CK1 of the first embodiment is used as one of the vehicle parts, for example, if the gaps G3 and G4 are left as voids, the parts may be damaged due to vibration or the like applied from the outside. and may be affected by changes in characteristics, etc. For this reason, as shown in FIG. 3, the cushioning member SP may be sandwiched between positions corresponding to the gaps G3 and G4. As a material for the buffer member SP, for example, plastic, insulating rubber, or the like can be considered.

The effect of the structure of the choke coil CK1 of the first embodiment described above will be described later together with the effect of the structure of the choke coil of the second embodiment, which will be described later.

(II) Second embodiment
Next, a choke coil according to a second embodiment, which is another embodiment of the present invention, will be described with reference to FIGS. 4 to 6. FIG. 4 shows the structure of the choke coil of the second embodiment, FIG. 5 shows the structure of the bobbin used in the choke coil, and FIG. It is a figure which shows the effect of each choke coil of embodiment. Further, in FIGS. 4 and 5, the same member numbers are given to the same members as the choke coil CK1 of the first embodiment, and the detailed explanation is omitted.

Each of the windings W11 and W12 used in the choke coil CK1 of the first embodiment described above has a circular cross-sectional shape. On the other hand, the winding used for the choke coil of the second embodiment has a rectangular cross-sectional shape. That is, the winding used for the choke coil of the second embodiment is a so-called rectangular wire. Along with this, the shape of the bobbin used for the choke coil of the second embodiment has a structure suitable for using a rectangular wire as the winding.

As shown in FIGS. 4 and 5, in the choke coil CK2 of the second embodiment, cores C11 and C12 having the same structure as the cores C11 and C12 in the choke coil CK1 of the first embodiment are replaced with the cores C11 and C12 of the first embodiment. In the same manner as the choke coil CK1, for example, they are combined vertically and used. At this time, as in the case of the choke coil CK1 of the first embodiment, a gap G3 is provided between the common shaft 3 and the common shaft 3C with the buffer member SP interposed therebetween. 4C is provided with a gap G4 across the buffer member SP.

Next, in the choke coil CK2 of the second embodiment, between the winding shaft 1, the winding shaft 1C, and the coil CL21 wound thereon (that is, the coil CL21 made of the flat wire winding W21), and the winding shaft 2 and the winding shaft 2C and the coil CL22 wound thereon (that is, the coil CL22 made of the winding W22, which is a flat wire), according to the second embodiment. do.

In the choke coil CK2 of the second embodiment, a bobbin B21 whose structure is illustrated in FIG. 5 and a bobbin B22 having the same shape as the bobbin B21 are combined so that their meshing portions 11A are alternately meshed. be done. At this time, the bobbin B21 is inserted between the winding shafts 1 and 1C and the coil CL21 (winding W21) wound thereon, and the bobbin B22 is wound on the winding shafts 2 and 2C. It is inserted between the coil CL22 (winding W22). In the following description, when describing matters common to the bobbin B21 and the bobbin B22 of the second embodiment, these are simply referred to as "the bobbin B21 and the like".

5, the bobbin B21 of the second embodiment is a cylindrical body through which the winding shaft 1 and the winding shaft 1C are passed and the coil CL21 is wound around the outer periphery of the bobbin B21. 15, flanges 16A and 17 that define the range in which the coil CL21 is wound in the trunk portion 15, the base portion 10, and the two upper and lower meshing points for engaging the bobbin B21 and the bobbin B22 so as to face each other. 11A and . At this time, while the trunk portion 15 and the flange 17 on the side of the base portion 10 are integrally formed, the trunk portion 15 and the flange 16A are separate members. After the coil CL21 made of the winding wire W21, which is a rectangular wire, is wound around the body portion 15, the flange 16A is joined to the body portion 15, thereby completing the bobbin 21 around which the coil CL21 is wound. ing.

As described above, the bobbin B22 of the second embodiment also has the same structure as the bobbin B21 shown in FIG. As the material of the bobbin B21 and the like, for example, resin such as plastic is used. 5, the bobbin B21 and the bobbin B22 are combined so that the meshing portion 11A of the bobbin B21 and the meshing portion 11A of the bobbin B22 face each other and mesh with each other. 1 and the winding shaft 1C and the winding shaft 2 and the winding shaft 2C are passed through, and the coil CL21 and the coil CL22 are wound around the outer circumferences of the respective flanges 16A and 17 while the positions are defined by the respective flanges 16A and 17. It is used for the choke coil CK1 of one embodiment.

On the other hand, as described above, in the choke coil CK2 of the second embodiment, the cores C11 and C12 having the structures described above are combined in the same manner as the choke coil CK1 of the first embodiment. The winding shaft 1 and the winding shaft 1C facing each other are inserted into the body portion 15 of the bobbin B21 having the flange 16A and the flange 17, and the rectangular wire constituting the coil CL21 is provided outside the bobbin B21. A winding W21 is wound by the required number of turns. The winding shaft 2 and the winding shaft 2C, which face each other, are inserted into the body portion 15 of the bobbin B22 similarly provided with a flange 16A and a flange 17. A flat wire constituting the coil CL22 is provided on the outer circumference of the bobbin B22. A barrel winding W22 is wound by the required number of turns. Copper, for example, is also used as a material for these windings W21 and W22. Both ends of the winding W21 toward the outside of the choke coil CK1 are connected to the outside of the choke coil CK2 via an external connection terminal TW21. Both ends of the winding W22 toward the outside of the choke coil CK2 are connected to the outside of the choke coil CK2 via the external connection terminals TW22. For these reasons, in the base portion 10 of each of the bobbins B21 and B22, the flat wire grooves TGH in which the external connection terminals TW21 and TW22 are fitted are the grooves TG similar to the bobbins B11 and B12 of the first embodiment. is attached to. Furthermore, the number of turns of the winding W21 in the coil CL21 and the number of turns of the winding W22 in the coil CL22 are preferably the same. The groove TG corresponds to an example of the "first external terminal portion" of the present invention, and the flat wire groove TGH corresponds to an example of the "second external terminal portion" of the present invention.

As described above, according to the structure of the choke coil CK1 of the first embodiment and the structure of the choke coil CK2 of the second embodiment, the gap G3 is provided between the common shaft 3 and the common shaft 3C facing each other. A gap G4 is provided between the common shaft 4 and the common shaft 4C, which are also opposed to each other. The length of each of the gap G3 and the gap G4 (the length of the air gap) corresponds to the magnitude of the common mode inductance that the choke coil CK1 of the first embodiment or the choke coil CK2 of the second embodiment should have. It is said. Therefore, one choke coil (the choke coil CK1 of the first embodiment or the choke coil CK2 of the second embodiment) can generate both the normal mode inductance and the common mode inductance, thereby generating the inductance of each mode. It is possible to downsize the choke coil capable of Therefore, when the structure of the choke coil CK1 of the first embodiment and the choke coil CK2 of the second embodiment are used as members of, for example, a noise filter, it is possible to reduce the size of the noise filter, increase the output, and improve the performance. .

Further, according to the structure of the bobbin B21 and the bobbin B22 of the second embodiment, one flange 17 and the trunk portion 15 constituting them are integrally formed, and the other flange 16A is the coil CL21 or the coil CL21 for the trunk portion 15. Since it has a structure in which it is connected to the body portion 15 after winding the coil CL22 (see FIG. 5(b) or FIG. 5(c)), even if the wire wound around the coil has a circular cross-section, Even if it is a square rectangular wire, the coil can be easily wound around the bobbin B21 or the bobbin B22.

Furthermore, according to the structure of the bobbin B21 and the bobbin B22 of the second embodiment, since the base portion 10 constituting the bobbin is provided with the groove TG and the exclusive rectangular groove TGH, parts can be used in common for windings having different cross-sectional shapes. It is possible to realize cost reduction by reducing the cost.

Here, experimental results (simulation results) by the inventors of the present application will be shown with respect to the effect of providing the gap G3 and the gap G4 in the choke coil CK1 of the second embodiment and the choke coil CK2 of the second embodiment. A more specific description will be given with reference to FIG. In the experiment whose results are shown in FIG. 6, a ferrite material with a magnetic permeability of 7,000 microhenries was used as the material of the core C11 and the like used in the choke coil CK1 of the first embodiment and the choke coil CK2 of the second embodiment. , the number of turns of the coil CL11, etc. is 13 times.

That is, when reducing noise over a wide frequency band (several kilohertz to about 30 megahertz) using an input filter circuit including an AC input IN, a fuse F, and a capacitor CD1 and a capacitor CD2 illustrated in FIG. In addition, when trying to generate both normal mode inductance and common mode inductance, conventionally, normal mode choke coil CKX1, normal mode choke coil CKX2 and common mode choke coil CKX3 as illustrated in FIG. of three choke coils were required. On the other hand, in the case of the choke coil CK1 of the first embodiment or the choke coil CK2 of the second embodiment, by providing the gap G3 and the gap G4, one Only by providing the choke coil CK1 or the choke coil CK2, a necessary normal mode inductance can be obtained in addition to the common mode inductance. As a result, a choke coil capable of generating two modes of inductance can be miniaturized.

The relationship between the lengths of the gaps G3 and G4 (the lengths of the air gaps) and the values of the normal mode inductances obtained from them is illustrated in FIG. Experimental results are available. According to this experimental result, it can be seen that a normal mode inductance with good flatness with respect to the driving current is generated when the gap G3 and the gap G4 exist. The maximum normal mode inductance (67.1 microhenries) is obtained when the length of each of the gaps G3 and G4 is 2 millimeters. This means that the desired normal mode inductance can be obtained by varying the lengths of the gaps G3 and G4.

(III) Third embodiment
Next, a choke coil according to a third embodiment, which is still another embodiment of the present invention, will be described with reference to FIG. FIG. 7 is a diagram showing the structure of the choke coil of the third embodiment. In FIG. 7, the same member numbers are given to the same members as the choke coil CK1 of the first embodiment or the choke coil CK2 of the second embodiment, and detailed explanations are omitted.

The entirety of the core C11 and the like used in the choke coil CK1 of the first embodiment described above is made of the same material (for example, ferrite material or the like). On the other hand, cores used in the choke coil of the third embodiment and the choke coil of the fourth embodiment, which will be described later, have the top surface, the winding axis, and the common axis formed of a plurality of types of materials. At this time, the choke coils of the third embodiment and the choke coils of the fourth embodiment are choke coils through which currents controlled by an interleave control method are respectively flowed, for example choke coils used as inductors for transformers. be.

That is, as shown in FIG. 7, in the choke coil CK3 of the third embodiment, the core C31 and the core C32 having the same shape as the core C31 are arranged vertically, for example, so that the end surfaces of the respective axes face each other. Used in combination. In the following description, when describing matters common to the core C31 and the core C32 of the third embodiment, these are simply referred to as "core C31 and the like".

In particular, as shown in an external perspective view of FIG. 7(b), the core C31 of the third embodiment has a substantially flat plate-like top surface 25 and columnar common shafts 23 and 24, which are integrally formed. is formed. On the other hand, as shown in FIG. 7, the core C32 of the third embodiment also has the same shape as the core C31 and is formed by integral molding. A columnar common shaft 23C and a common shaft 24C are integrally formed. At this time, the core C31 and the core C32 are made of the same ferrite material as a whole. In addition, the top surface 25 and the top surface 25C have substantially the same shape as the top surface 5 and the top surface 5C of the first embodiment, respectively (excluding recesses in which the winding shaft 21 and the winding shaft 22, which will be described later, respectively abut). is doing. On the other hand, the common shaft 23 and the common shaft 24 have the same cross-sectional shape as the common shaft 3 and the common shaft 4 of the first embodiment, respectively, but have the same length. longer than shaft 3 and common shaft 4; In addition, the common shaft 23C and the common shaft 24C have the same cross sections as those of the common shaft 3C and the common shaft 4C of the first embodiment, respectively, but their lengths are similar to those of the common shaft 3C. and longer than the common axis 4C. Accordingly, when the core C31 and the core C32 are used as the choke coil CK3 of the third embodiment, the gaps G3 and G4 (see FIG. 1 etc.) of the first embodiment are not formed as shown in FIG. , the end face of the common shaft 23 and the end face of the common shaft 23C abut, and the end face of the common shaft 24 and the end face of the common shaft 24C also abut.

On the other hand, in the choke coil CK3 of the third embodiment, the winding shaft 21 and the winding shaft 22 are separate members from the core C31 and the core C32. ing. Then, as shown in FIG. 7, the corresponding shafts of the core C31 and the like (that is, the end surfaces of the common shafts 23 and 24 shown in FIG. 7, and the common shafts 23C and 24C corresponding to the core C32) The core C31 and the core C32 are combined vertically, for example, so that the end surfaces of the core C31 and the core C32 are sandwiched between the core C31 and the core C32, and the winding shaft 21 and the winding shaft 22 are sandwiched between the cores C31 and C32. Used for coil CK3. At this time, the positions of the common shaft 23 and the common shaft 24 and the winding shafts 21 and 22 with respect to the top surface 25 are the common shafts 3 and 4 and the winding shafts 1 and 22 of the choke coil CK1 of the first embodiment. 2 are the same as the positions with respect to the top surface 5 . Further, the positions of the common shafts 23C and 24C and the winding shafts 21 and 22 with respect to the top surface 25C are the same as the common shafts 3C and 4C and the winding shafts 1C and 2C of the choke coil CK1 of the first embodiment. It is the same as the position with respect to each top surface 5C. Furthermore, the winding shaft 21 and the winding shaft 22 are sandwiched so as to abut against the recesses of the top surface 25C of the core C31 and the top surface 25C of the core C32.

Here, the magnetic permeability of the ferrite material which is the material of the core C31 consisting of the top surface 25 and the common shafts 23 and 24 and the core C32 consisting of the top surface 25C and the common shafts 23C and 24C is 2,000 microhenries. 3,000 microhenries, while the magnetic permeability of the dust material used for the winding shafts 21 and 22 is 20 to 30 microhenries. That is, the ratio of the magnetic permeability of the ferrite material to the magnetic permeability of the dust material is 100:1.

Furthermore, as the choke coil CK3 of the third embodiment, the volume of either the winding shaft 21 or the winding shaft 22 is v1 , and the total volume of the common shaft 23, the common shaft 23C and the common shaft 24, the common shaft 24C (that is, the volume of the common shaft 23, the common shaft 23C, the common shaft 24, and the common shaft 24C in the entire choke coil CK3 ) is v2, and the volume of either the top surface 25 or the top surface 25C is v3, the relationship shown in the following formula (1) is established.
v1: v2: v3 = 1: 1.3 or more and 1.4 or less: 2.6 or more and 2.8 or less (1)
More preferably, the volume ratio is v1:v2:v3=1:1.3:2.6.

On the other hand, the bobbin used for the choke coil CK3 of the third embodiment has the same configuration as the bobbin B21 and bobbin B22 used for the choke coil CK2 of the second embodiment. A coil CL11 composed of a winding wire W11 is wound around the body portion 15 of the bobbin B21. On the other hand, on the bobbin B22, a coil CL12 composed of a winding W12 is wound on the outer side of the body portion 15, and the winding shaft 22 is passed through the inner side of the body portion 15 of the bobbin B22.

The effects of the structure of the choke coil CK3 of the third embodiment described above will be described later together with the effects of the structure of the choke coil of the fourth embodiment, which will be described later.

(IV) Fourth embodiment
Finally, a choke coil according to a fourth embodiment, which is still another embodiment of the present invention, will be described with reference to FIGS. 8 and 9. FIG. 8 is a diagram showing the structure of the choke coil of the fourth embodiment, and FIG. 9 is a current-inductance characteristic diagram of each of the choke coil CK3 of the third embodiment and the choke coil of the fourth embodiment. Further, in FIG. 8, the same member numbers are assigned to the same members as any of the choke coils CK1 to CK3 of the first embodiment to the choke coil CK3 of the third embodiment, and detailed description thereof will be omitted.

In the choke coil CK3 of the third embodiment described above, the top surface 25, the common shaft 23 and the common shaft 24 are integrally formed using a ferrite material, and the top surface 25C, the common shaft 23C and the common shaft 24C are made of ferrite. It was integrally molded using the material. Furthermore, the winding shaft 21 and the winding shaft 22 are formed as separate parts using a dust material. On the other hand, the core C4 used in the choke coil of the fourth embodiment has its top surface made of a ferrite material, while both the winding shaft and the common shaft are made of a dust material.

That is, as shown in FIG. 8, in the choke coil CK4 of the fourth embodiment, common shafts 33 and 34 made of dust material and winding shaft 21 are placed between top surface 35 and top surface 35C made of ferrite material. A core C4 as a choke coil CK4 is formed with the winding shaft 22 sandwiched therebetween. At this time, the shapes of the common shaft 33 and the common shaft 34 are the same as the shapes of the winding shafts 21 and 22, respectively.

On the other hand, the top surface 35 and the top surface 35C have substantially the same shape as the top surface 5 and the top surface 5C of the first embodiment (the winding shaft 21 and the winding shaft 22 and the common shaft 33 and the common shaft 34 are respectively abutted). (excluding recesses). At this time, the positions of the common shaft 33, the common shaft 34, the winding shaft 21, and the winding shaft 22 with respect to the top surface 35 and the top surface 35C, respectively, are the common shafts 3, 4, and winding shafts of the choke coil CK1 of the first embodiment. 1 and winding shaft 2 with respect to the top surface 5, or the positions of the common shafts 3C and 4C and the respective winding shafts 1C and 2C with respect to the top surface 5C. Further, the winding shafts 21 and 22 and the common shafts 33 and 34 are sandwiched so as to abut against the concave portions of the top surfaces 35 and 35C.

Further, the ratio of the magnetic permeability of the ferrite material, which is the material of the top surface 35 and the top surface 35C, to the magnetic permeability of the tast material, which is the material of each of the winding shafts 21 and 22 and the common shafts 33 and 34, is This is the same as the ratio between the magnetic permeability of the ferrite material and the magnetic permeability of the dust-based material used in the choke coil CK3 of the third embodiment. In addition, the volume of either the winding shaft 21 or the winding shaft 22, the volume of the common shaft 33 and the volume of the common shaft 34 combined (that is, the volume of two common shafts), the top surface 35 or the top surface The volume ratio of either one of the surfaces 35C is also the same as the volume ratio of the top surface 25 and the like in the choke coil CK3 of the third embodiment.

On the other hand, the bobbin used for the choke coil CK4 of the fourth embodiment has the same configuration as the bobbin B21 and bobbin B22 used for the choke coil CK2 of the second embodiment. A coil CL21 made of a flat wire W21 is wound around the body portion 15 of the bobbin B21. On the other hand, the bobbin B22 has a coil CL22 made of a flat wire W32 wound around its body 15, and the winding shaft 22 passes through its body 15 inside.

As described above, according to the structure of the choke coil CK3 of the third embodiment and the structure of the choke coil CK4 of the fourth embodiment, the top surfaces 25 and 25C and the top surfaces 35 and 35C are made of ferrite material. The winding shaft 21 and the winding shaft 22 are made of a dust material, the common shafts 24C and 24 and the common shafts 23C and 23 of the third embodiment are made of a ferrite material, while the common shafts 23C and 23 of the fourth embodiment are made of a ferrite material. Since the shaft 33 and the common shaft 34 are made of a dust-based material, it is possible to increase the current of the choke coil by improving the DC superposition characteristics. Therefore, for example, when the choke coil CK3 of the third embodiment and the choke coil CK4 of the fourth embodiment are used as members of a transformer, it is possible to reduce the size of the transformer, make it compatible with high output, and improve its performance.

Further, since the relationship between the magnetic permeability of the ferrite material and the magnetic permeability of the dust-based material used in the choke coil CK3 of the third embodiment or the choke coil CK4 of the fourth embodiment is 100:1, the choke coil can further improve the DC superimposition characteristics of

Furthermore, in the choke coil CK3 of the third embodiment, the volume v1 for either one of the winding shafts 21 or 22, the volumes of the common shafts 23 and 23C, and the volumes of the common shafts 24 and 24C are combined. The ratio of the volume v2 and the volume v3 of either the top surface 25 or the top surface 25C is v1: v2: v3 = 1: 1.3 or more and 1.4 or less: 2.6 or more and 2.8 or less Therefore, the DC superposition characteristic of the choke coil can be further improved. This point is the same for the choke coil CK4 of the fourth embodiment.

Note that the relationship between the difference in the materials of the top surface 25 and the like used in the choke coil CK3 of the third embodiment and the DC superimposition characteristics obtained therefrom was obtained by the inventors of the present application as an example of the experimental results shown in FIG. is obtained. In FIG. 9, the graph indicated by the "□" mark shows the relationship between the drive current and the inductance when the choke coil CK3 of the third embodiment (thickness of the top surface 25 and the top surface 25C is 9.6 mm) is used. The graph indicated by the "▴" mark shows the relationship between the driving current and the inductance when the thickness of the top surface 25 and the top surface 25C is half that of the choke coil CK3 of the third embodiment. showing relationships. Furthermore, the graph indicated by the "♦" mark shows the relationship between the drive current and the inductance when the choke coil CK4 of the fourth embodiment (thickness of the top surface 35 and top surface 35C is 9.6 mm) is used. The graph indicated by the "●" mark is a comparative example in which the core (including the top surface, common shaft, and winding shaft) that constitutes the choke coil is all made of a dust-based material and the thickness of the top surface is It shows the relationship between the drive current and the inductance when the height is assumed to be the same as in the graph indicated by the "▴" mark. According to the experimental results shown in FIG. 9, the structure of the choke coil CK4 of the fourth embodiment is the most desirable for the desired DC superposition characteristics, followed by the structure of the choke coil CK3 of the third embodiment. I know. On the other hand, when all the cores constituting the choke coil are made of a dust-based material, the desired DC superimposition characteristics cannot be obtained due to a decrease in the inductance value when compared with the same number of turns. I know.

INDUSTRIAL APPLICABILITY As described above, the present invention can be used in the field of choke coils, and particularly when applied to the field of choke coils aimed at miniaturization and high performance, particularly remarkable effects can be obtained. .

1, 1C, 2, 2C, 21, 22 Winding axis 3, 3C, 4, 4C, 23, 23C, 24, 24C, 33, 34 Common axis 3T, 4T, 3CT, 4CT End face 5, 5C, 25, 25C, 35, 35C top surface 10 base portion 11, 11A meshing portion 15 trunk portion 16, 16A, 17 flange F fuse CK1, CK2, CK3, CK4 choke coil C11, C12, C31, C32, C4 core G3, G4 gap CL11, CL12, CL21, CL22 Coil B11, B12, B21, B22 Bobbin W11, W12, W21, W22 Winding TW11, TW12, TW21, TW22 External connection terminal TG Groove SP Buffer member TGH Groove for flat wire IN AC input section CD1, CD2 Capacitor CKX1 , CKX2 Normal mode choke coil CKX3 Common mode choke coil

Claims (6)

two first shafts each having a coil wound thereon via an insulating bobbin, the first shafts being parallel to each other and each having a columnar shape;
two second shafts parallel to each other and each having a columnar shape, the second shafts being parallel to the first shaft;
A plate-like connection portion connecting an end portion of each of the first shafts and an end portion of each of the second shafts corresponding to the end portion, the magnetic flux generated by the current flowing through each of the coils. through the first shaft and the second shaft; and
each provided with two cores used facing each other; and
two said bobbins with each said first shaft threaded inside and said coil wound outside;
the coils wound around the first shaft via the bobbins;
with
The end portions of each of the cores on the second axis opposite to the connecting portion and facing each other are separated by a length corresponding to the value of the normal mode inductance to be provided as the choke coil. A choke coil characterized by two first shafts each having a coil wound thereon via an insulating bobbin, the first shafts being parallel to each other and each having a columnar shape;
two second shafts parallel to each other and each having a columnar shape, the second shafts being parallel to the first shaft;
A plate-like connection portion connecting an end portion of each of the first shafts and an end portion of each of the second shafts corresponding to the end portion, the magnetic flux generated by the current flowing through each of the coils. through the first shaft and the second shaft; and
two cores each provided with a
two said bobbins with each said first shaft threaded inside and said coil wound outside;
the coils wound around the first shaft via the bobbins;
with
the connecting part is made of a ferrite material,
the first shaft is made of a dust-based material,
A choke coil, wherein the second shaft is made of either the ferrite material or the dust material. In the choke coil according to claim 2,
The relationship between the magnetic permeability μ1 of the ferrite material and the magnetic permeability μ2 of the dust material is
A choke coil characterized by μ1:μ2=100:1. In the choke coil according to claim 2 or 3,
A total volume v2 obtained by combining the volume v1 of one of the first shafts constituting one core and the volume of the two second shafts constituting the core, and the volume v3 of the connecting portion constituting the core and the relationship between
v1:v2:v3=1: 1.3 or more and 1.4 or less: 2.6 or more and 2.8 or less. In the choke coil according to any one of claims 1 to 4,
The bobbin is
a trunk around which the coil is wound;
flanges on opposite ends of the barrel defining the extent of the barrel around which the coil is wound;
with
The one flange and the body are integrally molded,
A choke coil comprising a structure in which the other flange is connected to the body after the coil is wound around the body. In the choke coil according to any one of claims 1 to 4,
The bobbin is
a trunk around which the coil is wound;
flanges at both ends of the body defining a range around which the coil is wound;
a first external terminal portion to which a winding having a circular cross section is attached;
a second external terminal portion, which is a second external terminal portion to which a winding having a rectangular cross section is attached and which is arranged side by side with the first external terminal portion;
A choke coil characterized by comprising:

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