Inductor

Abstract

This inductor comprises: a magnetic body; and a first conductor and a second conductor that are a pair of conductors. The magnetic body has a first surface and a second surface that face away from each other. The first conductor and the second conductor are disposed at least inside the magnetic body. The first conductor is columnar and is disposed so as to penetrate the first surface and the second surface. An insulating film is provided to the outer circumference of the first conductor. The second conductor is disposed so as to penetrate the first surface and the second surface, and faces at least a section of the outer circumference of the first conductor with the insulating film interposed therebetween.

Description

Inductor

[0001] The present disclosure relates to an inductor used in a power supply circuit or the like.

[0002] In recent years, in large-scale integrated circuits such as CPUs, the voltage has been decreasing, and the current flowing through power supply circuits and the like has been increasing. To cope with this increase in current, a multi-phase power supply system has become the mainstream. Also, a coupling system has been used as a power supply system corresponding to this system.

[0003] As an example of an inductor used in a power supply circuit or the like, Patent Document 1 discloses a magnetic coupling element including an inductor including a first conductor, a second conductor, and a magnetic body. In this magnetic coupling element, each of the first conductor and the second conductor is formed of a plate-like conductive member.

[0004] Japanese Patent Application Laid-Open No. 2005-129590

[0005] In the inductor shown in Patent Document 1, there is a limit to improving the coupling coefficient between the first conductor and the second conductor.

[0006] An inductor according to an aspect of the present disclosure includes a magnetic body, a first conductor and a second conductor which are a pair of conductors, the magnetic body has a first surface and a second surface facing each other, the first conductor and the second conductor are provided at least inside the magnetic body, the first conductor is cylindrical, is arranged so as to penetrate the first surface and the second surface, an insulating film is provided on the outer periphery of the first conductor, the second conductor is arranged so as to penetrate the first surface and the second surface, and faces at least a part of the outer periphery of the first conductor through the insulating film.

[0007] According to the present disclosure, the coupling coefficient in the inductor can be improved.

[0008] Figure 1 is a perspective view of an inductor according to Embodiment 1. Figure 2 is a schematic diagram of the longitudinal section of the inductor according to Embodiment 1. Figure 3 is a schematic diagram of the cross-section of the inductor according to Embodiment 1. Figure 4 is a perspective view of the first conductor included in the inductor of Embodiment 1. Figure 5 is a perspective view of the second conductor included in the inductor of Embodiment 1. Figure 6 is a diagram showing an example of a substrate module on which the inductor of Embodiment 1 is mounted. Figure 7 is a flowchart showing a method for manufacturing the inductor according to Embodiment 1. Figure 8 is a diagram showing an example of a method for forming the magnetic material of the inductor according to Embodiment 1. Figure 9 is a perspective view of an inductor according to a modified example of Embodiment 1. Figure 10 is a schematic diagram of the cross-section of an inductor according to a modified example of Embodiment 1. Figure 11 is a diagram showing an example of a method for combining the first and second conductors of the inductor according to a modified example of Embodiment 1. Figure 12 is a diagram showing the coupling coefficient and inductance value when the opening angle of the opening of the second conductor of the inductor shown in Embodiment 1 and the modified example is changed. Figure 13 is a perspective view of an inductor according to Embodiment 2. Figure 14 is a schematic diagram of the cross-section of an inductor according to Embodiment 2. Figure 15 is a diagram showing an example of a substrate module on which the inductor according to Embodiment 2 is mounted. Figure 16 is a perspective view of an inductor according to Embodiment 3. Figure 17 is a schematic cross-sectional view of an inductor according to Embodiment 3. Figure 18 is a diagram showing a cross-sectional view of an inductor according to Modification 1 of Embodiment 3. Figure 19 is a diagram showing another example of an inductor according to Modification 1 of Embodiment 3. Figure 20 is a schematic cross-sectional view of an inductor according to Modification 2 of Embodiment 3. Figure 21 is a schematic cross-sectional view of an inductor according to Modification 3 of Embodiment 3. Figure 22 is a schematic cross-sectional view of an inductor according to Modification 4 of Embodiment 3. Figure 23 is a diagram showing the coupling coefficient and inductance value when the rotation angle of the opening of the second conductor of the inductor shown in Embodiment 3 and Modifications 1 and 4 is changed.

[0009] The embodiments will be described in detail with reference to the drawings.

[0010] The embodiments described below are all specific examples of this disclosure. The numerical values, shapes, materials, components, arrangement positions of components, connection configurations, steps, and the order of steps shown in the following embodiments are examples only and are not intended to limit this disclosure. Furthermore, any components in the following embodiments that are not described in an independent claim will be described as optional components.

[0011] Furthermore, in this specification, terms indicating relationships between elements such as parallelism, terms indicating the shape of elements such as rectangular prisms, and numerical ranges do not represent only strict meanings, but also include substantially equivalent ranges, such as differences of a few percent.

[0012] Furthermore, each figure is a schematic diagram that has been appropriately emphasized, omitted, or had its proportions adjusted to illustrate this disclosure, and is not necessarily a strict representation; it may differ from the actual shape, positional relationships, and proportions. In each figure, substantially identical components are denoted by the same reference numerals, and redundant explanations may be omitted or simplified.

[0013] Furthermore, each figure shows the X, Y, and Z axes, representing three mutually orthogonal directions, and these axes and the axial directions along them are used for explanatory purposes as needed. Note that these axes are included for explanatory purposes only and do not limit the direction or orientation in which the inductor is used.

[0014] (Embodiment 1) [Inductor Configuration] The configuration of the inductor according to Embodiment 1 will be described with reference to Figures 1 to 6.

[0015] Figure 1 is a perspective view of the inductor 1 according to Embodiment 1. Figure 2 is a schematic diagram of the longitudinal section of the inductor 1. Figure 3 is a schematic diagram of the cross-section of the inductor 1. Figure 4 is a perspective view of the first conductor 30 included in the inductor 1. Figure 5 is a perspective view of the second conductor 40 included in the inductor 1.

[0016] Figure 1(a) shows an external perspective view of the inductor 1, and Figure 1(b) shows a transparent view of the first conductor 30 and the second conductor 40. Figure 2 shows a cross-section of the inductor 1 along line II-II in Figure 1(a). Figure 3 shows a cross-section of the inductor 1 along line III-III in Figure 2.

[0017] The inductor 1 shown in Figures 1 to 3 is a transinductor comprising a magnetic material 10 and a pair of conductors. The magnetic material 10 and the pair of conductors are integrally molded by pressure. The pair of conductors consists of a first conductor 30 and a second conductor 40. The first conductor 30 and the second conductor 40 are insulated from each other and face each other inside the magnetic material 10.

[0018] In the first embodiment, the inductor 1 consists of a cylindrical first conductor 30 and a second conductor 40 facing each other inside the magnetic material 10 with an insulating film si in between, making it possible to improve the coupling coefficient between the first conductor 30 and the second conductor 40.

[0019] Hereafter, the inductor 1 comprising the magnetic material 10 and a pair of conductors may be referred to as the transinductor 1. The following describes each component of the transinductor 1.

[0020] The magnetic body 10 shown in Figures 1 to 3 is a compacted magnetic core formed from a mixture of magnetic material powder and a binder. The magnetic body 10 can be formed using any magnetic material. Ferrite may be used as the magnetic material, or other magnetic materials may be used. For the metallic magnetic powder, particulate materials having a predetermined elemental composition such as Fe-Si-Al, Fe-Si, Fe-Si-Cr, or Fe-Si-Cr-B are used. The binder is a resin material such as a silicone resin, and a material capable of maintaining a certain shape by insulating the particles of the metallic magnetic powder while binding the particles together is selected.

[0021] The magnetic material 10 is molded into any shape by mold molding. The magnetic material 10 in this embodiment has a rectangular parallelepiped shape with an outer surface. For example, the magnetic material 10 has dimensions of 5 mm in the X-axis direction, 5 mm in the Y-axis direction, and 3.8 mm in the Z-axis direction. In this example, the dimensions in the Z-axis direction are smaller than the dimensions in the X-axis direction and the Y-axis direction. The dimensions of the magnetic material 10 are appropriately selected from the range of 2 mm to 15 mm for the X-axis direction, 2 mm to 15 mm for the Y-axis direction, and 1 mm to 5 mm for the Z-axis direction.

[0022] The magnetic material 10 has a bottom surface 18, a top surface 19, and four side surfaces connecting the bottom surface 18 and the top surface 19. The four side surfaces are composed of side surfaces 11a, 11b, 11c, and 11d. In this embodiment, the bottom surface 18 is referred to as the first surface f1, and the top surface 19 is referred to as the second surface f2.

[0023] The first surface f1, the second surface f2, and the sides 11a to 11d are all flat surfaces. The first surface f1 and the second surface f2 are parallel to each other and face away from each other in the Z-axis direction. Sides 11a and 11b face away from each other in the Y-axis direction. Sides 11c and 11d face away from each other in the X-axis direction.

[0024] The first surface f1 and the second surface f2, and the sides 11a to 11d extend in directions that intersect each other, specifically in orthogonal directions. Also, the sides 11a and 11b, and the sides 11c and 11d extend in directions that intersect each other, specifically in orthogonal directions.

[0025] Furthermore, the magnetic material 10 has corners connecting sides 11a and 11c, corners connecting sides 11a and 11d, corners connecting sides 11b and 11c, and corners connecting sides 11b and 11d. Each corner may have a rounded shape when viewed from a direction perpendicular to the second surface f2.

[0026] Each of the first conductor 30 and the second conductor 40 is formed of a conductive material. The conductive material is composed of a metallic material selected from, for example, metals such as copper, aluminum, silver, and gold, alloys containing one or more of these metals, and materials consisting of metals or alloys and other substances.

[0027] The first conductor 30 has a cylindrical shape, as shown in Figure 4. More specifically, as shown in Figure 2, the cylindrical first conductor 30 extends along a central axis c and has a circular top surface 31a through which the central axis c passes, a circular bottom surface 31b through which the central axis c passes and facing away from the top surface 31a, and a cylindrical outer circumference 31d that connects the top surface 31a and the bottom surface 31b, surrounds the central axis c, and extends along the central axis c. An insulating film si is formed on the outer circumference 31d of the first conductor 30. The insulating film si is an insulating coating that covers the outer circumference 31d of the first conductor 30. The insulating film si is formed from a resin material containing inorganic fillers such as silica and alumina, for example, a polyimide-based resin material. For example, the diameter of the first conductor 30 is 1.0 mm, and the thickness of the insulating film si is 0.02 mm. When viewed from a direction perpendicular to the second surface f2 of the magnetic material 10, the first conductor 30 is positioned at the center of the magnetic material 10 (see Figure 3). Figure 2 shows a cross-section parallel to the central axis c of the inductor 1, and Figure 3 shows a cross-section perpendicular to the central axis c of the inductor 1.

[0028] As shown in Figure 2, a portion of the first conductor 30 is provided inside the magnetic material 10, and the other portion of the first conductor 30 is provided outside the magnetic material 10. The first conductor 30 is positioned to penetrate the first surface f1 and the second surface f2 of the magnetic material 10. Specifically, the first conductor 30 extends in a straight line perpendicular to the first surface f1 and the second surface f2.

[0029] The first conductor 30 has protrusions 35 that project outward from the second conductor 40 in directions perpendicular to the first surface f1 and the second surface f2. The protrusions 35 are provided at each end of the first conductor 30. The protrusions 35 have exposed regions 36 where the outer circumference 31d of the first conductor 30 is exposed. The exposed regions 36 are not provided with an insulating film si, and the conductive material is exposed. For example, the height of the protrusions 35 is 0.1 mm, and the height of the exposed regions 36 is 0.05 mm. The portion of the exposed regions 36 corresponds to the external terminals of the first conductor 30 and is electrically connected to the circuit board when the transinductor 1 is mounted on the circuit board.

[0030] As shown in Figure 5, the second conductor 40 has a cylindrical opposing portion 41 and two flange-shaped terminal portions 42. Figure 5 shows the second conductor 40 with the opposing portion 41 and terminal portions 42 assembled, in other words, the second conductor 40 with the first conductor 30 and magnetic material 10 removed from the inductor 1.

[0031] As shown in Figure 2, a portion of the second conductor 40 is provided inside the magnetic material 10, and the other portion of the second conductor 40 is provided outside the magnetic material 10. The second conductor 40 is positioned to penetrate the first surface f1 and the second surface f2 of the magnetic material 10. Specifically, the second conductor 40 is positioned along the direction in which the first conductor 30 extends, perpendicular to the first surface f1 and the second surface f2. The second conductor 40 is provided outside the outer circumference 31d of the first conductor 30. The second conductor 40 faces the outer circumference 31d of the first conductor 30 via an insulating film si.

[0032] The opposing portion 41 of the second conductor 40 is linear and extends perpendicular to the first surface f1 and the second surface f2. As shown in Figures 2 and 3, the opposing portion 41 is located outside the outer circumference 31d of the first conductor 30, and the inner circumference of the opposing portion 41 is in contact with the insulating film si located on the outer circumference 31d of the first conductor 30. In other words, the opposing portion 41 faces the first conductor 30 via the insulating film si. The central axis of the cylindrical opposing portion 41 and the central axis c of the first conductor 30 are approximately coincident. The difference between the outer and inner diameters of the opposing portion 41, i.e., the thickness of the opposing portion 41, is, for example, 0.15 mm. When comparing the area of ​​the cross-section perpendicular to the direction of current flow, in this example, the cross-sectional area of ​​the first conductor 30 is larger than the cross-sectional area of ​​the opposing portion 41 of the second conductor 40.

[0033] The terminal portion 42 is a flat plate having a circular through hole. The thickness of the terminal portion 42 is, for example, 0.1 mm. The thickness of the terminal portion 42 can be appropriately selected from the range of 0.05 mm to 0.2 mm. One of the two terminal portions 42 is in contact with the first surface f1, and the other terminal portion 42 is in contact with the second surface f2. The two terminal portions 42 are each connected to both ends 41a of the cylindrical opposing portion 41. For example, the terminal portion 42 is made of the same material as the opposing portion 41 and is connected to the opposing portion 41 by welding. Alternatively, the terminal portion 42 may be connected to the opposing portion 41 by soldering material or the like. The terminal portion 42 corresponds to the external terminal of the second conductor 40 and is electrically connected to the circuit board when the transinductor 1 is mounted on the circuit board.

[0034] For example, the second conductor 40 is formed by connecting the planar portion of the terminal portion 42 to the end face which is the outermost edge of the opposing portion 41. If the opposing portion 41 is formed to penetrate the first surface f1 and the second surface f2, the second conductor 40 may be formed by connecting the inner surface of the through hole of the terminal portion 42 to the outer peripheral surfaces of both ends 41a of the opposing portion 41.

[0035] The transinductor 1 of this embodiment comprises a magnetic body 10 and a pair of conductors, a first conductor 30 and a second conductor 40. The magnetic body 10 has a first surface f1 and a second surface f2 facing away from each other. The first conductor 30 and the second conductor 40 are provided at least inside the magnetic body 10. That is, at least a part of the first conductor 30 and at least a part of the second conductor 40 are provided inside the magnetic body 10. The first conductor 30 is cylindrical and is arranged to penetrate the first surface f1 and the second surface f2. An insulating film si is provided on the outer circumference 31d of the first conductor 30. The second conductor 40 is arranged to penetrate the first surface f1 and the second surface f2 and faces the outer circumference 31d of the first conductor 30 via the insulating film si.

[0036] In this way, by arranging the second conductor 40 so as to face the outer circumference 31d of the cylindrical first conductor 30, the coupling coefficient in the transinductor 1 can be improved.

[0037] Figure 6 shows an example of a circuit board module 70 on which the inductor 1 is mounted. In Figure 6, the cross-sectional hatching is omitted.

[0038] The substrate module 70 shown in Figure 6 comprises a first circuit board 71, a second circuit board 72, power semiconductor components 73, a motherboard 75, a CPU component 76, and two transinductors 1. In the following, the negative side in the Z-axis direction will be referred to as "one side," and the positive side as "the other side."

[0039] Of the two main surfaces of the motherboard 75, one surface is soldered to the second circuit board 72, and the CPU component 76 is mounted on the other surface. Of the two main surfaces of the second circuit board 72, two transinductors 1 are mounted on one surface, and the other surface is soldered to the motherboard 75. Of the two main surfaces of the first circuit board 71, power semiconductor components 73 are mounted on one surface, and two transinductors 1 are mounted on the other surface. In this example, two transinductors 1 are provided between the first circuit board 71 and the second circuit board 72.

[0040] Of the two terminal portions 42 of the second conductor 40 of the transformer inductor 1, one terminal portion 42 is electrically connected to the first circuit board 71 via solder, and the other terminal portion 42 is electrically connected to the second circuit board 72 via solder.

[0041] Of the exposed regions 36 at both ends of the first conductor 30, one exposed region 36 is inserted into a through-hole 71h provided in the first circuit board 71 and is electrically connected to the first circuit board 71 via solder. The other exposed region 36 is inserted into a through-hole 72h provided in the second circuit board 72 and is electrically connected to the second circuit board 72 via solder. For example, when the first conductor 30 has a function as a primary coil and the second conductor 40 has a function as a secondary coil, the other exposed regions 36 of the two transformer inductors 1 may be electrically connected to each other by wiring provided on the other surface of the second circuit board 72.

[0042] According to the above configuration, a substrate module 70 including a transformer inductor 1 having a high coupling coefficient can be provided.

[0043] [Method for manufacturing an inductor] The method for manufacturing the transformer inductor 1 according to Embodiment 1 will be described with reference to FIGS. 7 and 8.

[0044] FIG. 7 is a flowchart showing a method for manufacturing the inductor 1.

[0045] As shown in FIG. 7, the transformer inductor 1 is manufactured by a first conductor forming step S110, a second conductor forming step S120, a magnetic body forming step S140, and a terminal portion connecting step S150.

[0046] The first conductor forming step S110 is a step of forming the first conductor 30. In this step, first, a copper wire covered with an insulating film si is cut to form a linear wire member. Then, the insulating films si at both ends of the wire member are removed to form exposed regions 36 where the conductive material is exposed at both ends of the wire member. The removal of the insulating film si is performed by, for example, laser processing or the like. Thereby, the first conductor 30 is formed.

[0047] The second conductor forming step S120 is a step of forming a part of the second conductor 40. In this step, a cylindrical copper member is cut to a length shorter than the above-described wire member. Thereby, a cylindrical facing portion 41 is formed. Note that the second conductor forming step S120 may be executed before the first conductor forming step S110.

[0048] Before press-molding the magnetic body 10, the first conductor 30 is inserted into the cylindrical facing portion 41. At this time, both ends of the first conductor 30 protrude to the outer sides of both end portions 41a of the facing portion 41.

[0049] The magnetic body forming step S140 is a step of press-molding the magnetic body 10 together with the first conductor 30 and the second conductor 40. In this step, the central portion excluding both portions where the protruding portion 35 of the first conductor 30 and the terminal portion 42 of the second conductor 40 are connected is placed in a mold and covered with a mixture containing magnetic material powder and a binder, and the protruding portion 35 of the first conductor 30 and the terminal portion 42 of the second conductor 40 are not covered with the mixture, and the magnetic body 10 is formed by press-molding. Note that the magnetic body forming step S140 may be executed by two-stage press-molding.

[0050] FIG. 8 is a diagram showing an example of a method of forming the magnetic body 10 of the inductor 1.

[0051] As shown in FIG. 8, first, a low-pressure molded member 10x molded by a first press with a pressure lower than the main compression molding is prepared. The low-pressure molded member 10x has a rectangular parallelepiped shape and has a through hole formed therein. Next, the facing portion 41, which is a part of the first conductor 30 and the second conductor 40, is inserted into the through hole formed in the low-pressure molded member 10x. Then, main compression molding is performed by a second press with a pressure higher than that of the first press. By performing two-stage press-molding in this manner, the magnetic body 10 in a state where a part of the first conductor 30 and the second conductor 40 are inserted may be molded.

[0052] The terminal portion connecting step S150 is a step of connecting the terminal portions 42 to both end portions 41a of the cylindrical facing portion 41. The terminal portions 42 are connected to both end portions 41a of the facing portion 41 by, for example, laser welding. By these steps, the transformer inductor 1 is manufactured.

[0053] Although the above example shows the formation of the exposed region 36 in the first conductor formation step S110, it is not limited to this. For example, the exposed region 36 may not be formed in the first conductor formation step S110, but rather formed in the terminal connection step S150 by connecting the terminal portion 42 and then removing a portion of the insulating film si of the protruding portion 35 with a laser.

[0054] Furthermore, although the above example shows the magnetic material 10 being press-molded together with the first conductor 30 and the second conductor 40 in the magnetic material formation step S140, the method is not limited to this. For example, a molding core having through holes may be prepared by this compression molding, and the first conductor 30 and the second conductor 40 may be inserted into the through holes of this molding core and bonded to form a magnetic material 10 with the first conductor 30 and the second conductor 40 inserted.

[0055] [Modification of Embodiment 1] The configuration of the transformer inductor 1A according to a modification of Embodiment 1 will be described with reference to Figures 9 to 11. In this modification, an example in which the second conductor 40 has an opening 44 will be described.

[0056] Figure 9 is a perspective view of an inductor 1A according to a modified example of Embodiment 1. Figure 10 is a schematic diagram of a cross-section of the inductor according to the modified example. Figure 10 shows the cross-section of the inductor 1A along the line X-X in Figure 9, that is, a cross-section perpendicular to the central axis c. In Figure 9, the magnetic material 10 is shown by a dashed line.

[0057] As shown in Figure 9, the modified transinductor 1A comprises a magnetic material 10 and a pair of conductors, a first conductor 30 and a second conductor 40. The configuration of the magnetic material 10 and the first conductor 30 is substantially the same as that of Embodiment 1. The configuration of the second conductor 40 will be described below.

[0058] The modified second conductor 40 is composed of an opposing portion 41 and two flange-shaped terminal portions 42. The configuration of the terminal portions 42 is the same as in the first embodiment.

[0059] In the modified example, the opposing portion 41 is positioned to penetrate the first surface f1 and the second surface f2 of the magnetic material 10. Specifically, the opposing portion 41 is positioned along the direction in which the first conductor 30 extends, perpendicular to the first surface f1 and the second surface f2.

[0060] As shown in Figure 10, the second conductor 40 inside the magnetic material 10 has an arc-shaped cross-section perpendicular to the direction that penetrates the first surface f1 and the second surface f2. In other words, the second conductor 40 has a facing portion 41 that faces the outer circumference 31d of the first conductor 30 and an opening 44 that does not face the first conductor 30.

[0061] The opposing portion 41 is positioned outside the outer circumference 31d of the first conductor 30. In this example, an insulating film si is formed along the outer circumference 31d of the first conductor 30, and the opposing portion 41 is positioned along this insulating film si. Since both the outer circumference 31d of the first conductor 30 and the insulating film si are curved surfaces, the opposing portion 41 positioned along them is also curved. The inner circumference of the opposing portion 41 is in contact with a part of the insulating film si located on the outer circumference 31d of the first conductor 30. In other words, the opposing portion 41 faces a part of the outer circumference 31d of the first conductor 30 via the insulating film si. The central axis of the arc-shaped opposing portion 41 and the central axis c of the first conductor 30 are approximately coincident. The difference between the outer and inner diameters of the opposing portion 41, i.e., the thickness (wall thickness) of the opposing portion 41, is, for example, 0.15 mm.

[0062] The opening 44 is an open region where the conductive material of the second conductor 40 is not formed, and is filled with the magnetic material 10. Specifically, the opening 44 is filled with the material of the magnetic material 10, and the material of the magnetic material 10 penetrates the opening 44 and comes into contact with the insulating film si. The opening angle θ of the opening 44 is appropriately selected from, for example, a range of 90° to 180°. The opening angle θ of the opening 44 is the value expressed as an angle of the region occupied by the opening 44 (the region where the opposing portion 41 does not exist) when the second conductor 40 is viewed from a direction along the central axis c of the first conductor 30, with the central axis c of the first conductor 30 as the central coordinate. That is, the opening angle θ is the angular distance between one end 441 and the other end 442 of the opening 44, centered on the central axis c in the direction in which the opening 44 opens in a cross section perpendicular to the central axis c of the inductor 1A. Note that the opening angle θ of the opening 44 may be selected from a range of 120° to 180°.

[0063] Figure 11 shows an example of a method for combining the first conductor 30 and the second conductor 40.

[0064] Figure 11 shows parts of the first conductor 30, the insulating film si, and the second conductor 40, illustrating how the first conductor 30 is inserted into the second conductor 40 from the side and assembled. As shown in this figure, when inserting the first conductor 30 through the opening 44 of the second conductor 40, insertion becomes difficult if the opening angle θ of the opening 44 is too small. Therefore, it is desirable to select the opening angle θ of the opening 44 from a range of 120° to 180°.

[0065] A modified transinductor 1A of Embodiment 1 comprises a magnetic body 10 and a pair of conductors, a first conductor 30 and a second conductor 40. The magnetic body 10 has a first surface f1 and a second surface f2 facing away from each other. The first conductor 30 and the second conductor 40 are provided at least inside the magnetic body 10. The first conductor 30 is cylindrical and is arranged to penetrate the first surface f1 and the second surface f2. An insulating film si is provided on the outer circumference 31d of the first conductor 30. The second conductor 40 is arranged to penetrate the first surface f1 and the second surface f2 and faces a part of the outer circumference 31d of the first conductor 30 via the insulating film si.

[0066] In this way, by arranging the second conductor 40 so as to face a part of the outer circumference 31d of the cylindrical first conductor 30, the coupling coefficient in the transinductor 1A can be improved.

[0067] [Effects, etc.] The effects of the transinductor 1 of Embodiment 1 and the modified transinductor 1A will be explained with reference to Figure 12.

[0068] Figure 12 shows the coupling coefficient and inductance values ​​when the opening angle θ of the opening 44 of the second conductor 40 of the inductors 1 and 1A shown in Embodiment 1 and modified examples is changed.

[0069] In Figure 12, the horizontal axis represents the opening angle θ of the opening 44 of the second conductor 40, the left vertical axis represents the coupling coefficient of the first conductor 30 and the second conductor 40, and the right vertical axis represents the inductance values ​​(self-inductance) of the first conductor 30 and the second conductor 40, respectively. Figures 12(a) to (d) show data when the opening angle θ of the opening 44 of the second conductor 40 is changed. The insulating film si is not shown in Figures 12(a) to (d).

[0070] Figure 12(a) shows the data for the transinductor 1 of Embodiment 1. Specifically, Figure 12(a) shows the data when the opening angle θ of the opening 44 of the second conductor 40 is 0°, that is, when the second conductor 40 covers the entire outer circumference 31d of the first conductor 30. In this example, the coupling coefficient of the transinductor 1 is 0.992, the inductance value of the first conductor 30 is 20.0 nH, and the inductance value of the second conductor 40 is 18.9 nH.

[0071] Figure 12(b) shows the data when the opening angle θ of the opening 44 is 90°. In this example, the coupling coefficient of the transinductor 1A is 0.988, the inductance value of the first conductor 30 is 22 nH, and the inductance value of the second conductor 40 is 20 nH.

[0072] Figure 12(c) shows the data when the opening angle θ of the opening 44 is 180°. In this example, the coupling coefficient of the transinductor 1A is 0.978, the inductance value of the first conductor 30 is 24 nH, and the inductance value of the second conductor 40 is 22 nH.

[0073] Figure 12(d) shows the data when the opening angle θ of the opening 44 is 270°. In this example, the coupling coefficient of the transinductor 1A is 0.960, the inductance value of the first conductor 30 is 27 nH, and the inductance value of the second conductor 40 is 24 nH.

[0074] Furthermore, in the magnetic coupling element disclosed in Patent Document 1, when the dimensions in the X-axis direction are 12 mm, the dimensions in the Y-axis direction are 11 mm, and the dimensions in the Z-axis direction are 5 mm, the coupling coefficient is 0.936 and the inductance value is 38.7 nH.

[0075] According to the first embodiment and the modified transinductor 1, 1A, the coupling coefficient can be increased compared to the magnetic coupling element disclosed in Patent Document 1. Furthermore, by providing an opening 44 as in the modified transinductor 1A, the inductance value can be increased compared to the transinductor 1 of the embodiment. In addition, in the structure of the modified transinductor 1A, the inductance value can be adjusted by changing the opening angle θ of the opening 44 of the second conductor 40.

[0076] (Embodiment 2) [Inductor Configuration] The configuration of the transinductor 1B according to Embodiment 2 will be described with reference to Figures 13 to 15. Embodiment 2 describes an example in which the transinductor 1B is composed of multiple pairs of conductors.

[0077] Figure 13 is a perspective view of the inductor 1B according to Embodiment 2. Figure 14 is a schematic cross-sectional view of the inductor 1B. Figure 14 shows the cross-section of the inductor 1B along the line XIV-XIV in Figure 13. Figure 13(a) shows an external perspective view of the transformer inductor 1B, and (b) shows a transparent view of the first conductors 30a, 30b and the second conductors 40a, 40b.

[0078] The transinductor 1B of Embodiment 2 comprises a magnetic material 10 and a plurality of pairs of conductive materials. The magnetic material 10 of Embodiment 2 has a dimension of 10 mm in the X-axis direction, which is twice the size of the magnetic material 10 of Embodiment 1. The other configurations of the magnetic material 10 are substantially the same as those of Embodiment 1.

[0079] The multiple pairs of conductors include a first pair of first conductors 30a and second conductors 40a, and a second pair of first conductors 30b and second conductors 40b. The configurations of the first conductors 30a and 30b are the same as those of the first conductor 30 in Embodiment 1, and they have central axes ca and cb, respectively, the same as the central axis c of the first conductor 30 in Embodiment 1. The configurations of the second conductors 40a and 40b are the same as those of the second conductor 40 in Embodiment 1. The opposing portions 41 of the second conductors 40a and 40b in Embodiment 2 are cylindrical. Figure 14 shows a cross-section of the transinductor 1B perpendicular to the central axes ca and cb.

[0080] Multiple pairs of conductors are arranged at predetermined intervals in a first direction d1 along the first surface f1. In other words, multiple pairs of conductors are arranged adjacent to each other in the first direction d1. Figures 13 and 14 show pairs of conductors consisting of two sets, but the number of pairs of conductors is not limited to two sets, and may be three or more sets.

[0081] In the second embodiment as well, the second conductor 40a (or 40b) is arranged to face the outer circumference 31d of the cylindrical first conductor 30a (or 30b), thereby improving the coupling coefficient in the transinductor 1B.

[0082] Figure 15 shows an example of a circuit board module 70 on which an inductor 1B is mounted.

[0083] The substrate module 70 shown in Figure 15 comprises a first circuit board 71, a second circuit board 72, a power semiconductor component 73, a motherboard 75, a CPU component 76, and a transinductor 1B having two pairs of conductors.

[0084] The configuration of the first circuit board 71, the second circuit board 72, the power semiconductor component 73, the motherboard 75, and the CPU component 76 is the same as in Embodiment 1. In this example, a transinductor 1B is provided between the first circuit board 71 and the second circuit board 72. Hereinafter, the negative side in the Z-axis direction will be referred to as "one side" and the positive side as "the other side."

[0085] Of the two terminal portions 42a of the second conductor 40a of the transinductor 1B, one terminal portion 42a is electrically connected to the first circuit board 71 via solder, and the other terminal portion 42a is electrically connected to the second circuit board 72 via solder. Similarly, of the two terminal portions 42b of the second conductor 40b, one terminal portion 42b is electrically connected to the first circuit board 71 via solder, and the other terminal portion 42b is electrically connected to the second circuit board 72 via solder.

[0086] Of the exposed regions 36a at both ends of the first conductor 30a, one exposed region 36a is inserted into a through-hole 71ha provided in the first circuit board 71 and electrically connected to the first circuit board 71 via solder. The other exposed region 36a is inserted into a through-hole 72ha provided in the second circuit board 72 and electrically connected to the second circuit board 72 via solder. Of the exposed regions 36b at both ends of the first conductor 30b, one exposed region 36b is inserted into a through-hole 71hb provided in the first circuit board 71 and electrically connected to the first circuit board 71 via solder. The other exposed region 36b is inserted into a through-hole 72hb provided in the second circuit board 72 and electrically connected to the second circuit board 72 via solder. For example, if the first conductors 30a and 30b function as primary coils and the second conductors 40a and 40b function as secondary coils, the other exposed regions 36a and 36b of the two first conductors 30a and 30b may be electrically connected to each other by wiring provided on the other side of the second circuit board 72.

[0087] According to the above configuration, a substrate module 70 equipped with a transinductor 1B with a high coupling coefficient can be provided. Furthermore, according to the above configuration, the mounting area can be reduced compared to, for example, the case in which multiple transinductors 1, each having a pair of conductors, are mounted on a circuit board.

[0088] (Embodiment 3) [Inductor Configuration] A transinductor 1C according to Embodiment 3 will be described. In this Embodiment 3, the second conductor 40 has an opening 44, and an example will be described in which the opening 44 of the second conductor 40a in the first set and the opening 44 of the second conductor 40b in the second set are arranged so that they do not face each other in the first direction d1.

[0089] Figure 16 is a perspective view of the inductor 1C according to Embodiment 3. Figure 17 is a schematic diagram of the cross-section of the inductor 1C. Figure 17 shows the cross-section of the inductor 1C along the line XVII-XVII in Figure 16, that is, the cross-section perpendicular to the central axes ca and cb.

[0090] The transinductor 1C of Embodiment 3 comprises a magnetic material 10 and a plurality of pairs of conductive materials. The configuration of the magnetic material 10 is substantially the same as that of Embodiment 2.

[0091] The multiple pairs of conductors include a first pair of first conductors 30a and second conductors 40a, and a second pair of first conductors 30b and second conductors 40b. The two pairs of conductors are arranged at a predetermined interval in a first direction d1 along a first surface f1. In this embodiment, the first direction d1 is the positive side in the X-axis direction. The second pair of first conductors 30b and second conductors 40b are located in the first direction d1 from the first pair of first conductors 30a and second conductors 40a. The two pairs of conductors are arranged adjacent to each other in the first direction d1. Specifically, the second pair of first conductors 30b and second conductors 40b are located in the first direction d1 from the first pair of first conductors 30a and second conductors 40a. The configuration of the first conductors 30a and 30b is the same as in Embodiment 1 or 2. The configuration of the second conductors 40a and 40b will be described below.

[0092] The second conductors 40a and 40b are each composed of an opposing portion 41 and two flange-shaped terminal portions 42. The configuration of the terminal portions 42 is the same as in Embodiment 1 or 2.

[0093] The opposing portion 41 is positioned to penetrate the first surface f1 and the second surface f2 of the magnetic material 10. Specifically, the opposing portion 41 is positioned along the direction in which the first conductors 30a and 30b extend, so as to be perpendicular to the first surface f1 and the second surface f2.

[0094] As shown in Figure 17, the second conductors 40a and 40b inside the magnetic material 10 have an arc-shaped cross-section perpendicular to the direction penetrating the first surface f1 and the second surface f2. The second conductor 40a inside the magnetic material 10 has a facing portion 41 that faces the outer circumference 31d of the first conductor 30a and an opening 44 that does not face the first conductor 30a. Similarly, the second conductor 40b inside the magnetic material 10 has a facing portion 41 that faces the outer circumference 31d of the first conductor 30b and an opening 44 that does not face the first conductor 30b. The configuration of the facing portion 41 and the opening 44 is the same as the modified example of Embodiment 1. In this example, the position where the opening 44 is formed differs for two sets of conductors adjacent to each other in the first direction d1.

[0095] As shown in Figure 17, the first set of second conductors 40a and the second set of second conductors 40b are arranged such that their respective openings 44 do not face each other in the first direction d1. For example, the opening angle θ of the respective openings 44 of the second conductors 40a and 40b is 180°, and the respective openings 44 face different directions. Specifically, the opening 44 of the second conductor 40a faces the negative side in the X-axis direction, and the opening 44 of the second conductor 40b faces the positive side in the X-axis direction. The opening 44 of the second conductor 40a is opened in a cross section perpendicular to the central axes ca and cb of the transinductor 1C, with an opening angle θ that is the sum of the opening angles θ / 2 in the clockwise and counterclockwise directions around the central axis ca, starting from the center line La extending from the central axis ca. Similarly, the opening 44 of the second conductor 40b is opened in the cross-section of the transinductor 1C with an opening angle θ that is the sum of the opening angles θ / 2 in both clockwise and counterclockwise directions around the central axis cb, starting from the center line Lb extending from the central axis cb.

[0096] Furthermore, at least one of the first set of second conductors 40a and the second set of second conductors 40b is positioned between the first set of first conductors 30a and the second set of first conductors 30b. Specifically, both the first set of second conductors 40a and the second set of second conductors 40b are positioned between the first set of first conductors 30a and the second set of first conductors 30b.

[0097] Furthermore, in this transinductor 1C, the rotation angle θa of the centerline La of the opening 44 of the second conductor 40a, with the central axis ca of the first conductor 30a in the first set as the rotation center, and the rotation angle θb of the centerline Lb of the opening 44 of the second conductor 40b, with the central axis cb of the first conductor 30b in the second set as the rotation center, differ by 90° or more and 180° or less (90° ≤ |θa - θb| ≤ 180°). In this example, the rotation angle θa of the opening 44 of the second conductor 40a in the first set and the rotation angle θb of the opening 44 of the second conductor 40b in the second set differ by 180°.

[0098] The rotation angle θa is the counterclockwise angle of the center line La, with the reference axis Ra extending from the central axis ca in the first direction d1, relative to the central axis ca, in a cross section perpendicular to the central axes ca and cb of the transinductor 1C, and represents the position of the center (center in the direction of rotation) of the opening 44 of the second conductor 40a. In this case, the boundary line between the first and fourth quadrants in the plane coordinate system is used as the reference, and the angle of this boundary line is set to 0°. The rotation angle θb is the counterclockwise angle of the center line Lb, with the reference axis Rb extending from the central axis cb in the first direction d1, relative to the central axis Rb, in the above cross section of the transinductor 1C, and represents the rotation angle of the center (center in the direction of rotation) of the opening 44 of the second conductor 40b. The difference between the rotation angles θa and θb, |θa - θb|, is the relative angle between the rotation angles θa and θb, and is expressed in the range of 0° to 180°.

[0099] According to the conductor arrangement structure shown in Embodiment 3, magnetic coupling between two sets of conductors adjacent to each other in the first direction d1 can be suppressed.

[0100] [Modification 1 of Embodiment 3] A transformer inductor 1C according to Modification 1 of Embodiment 3 will be described. In this Modification 1, an example will be described in which the openings 44 in the first set and the openings 44 in the second set are arranged so that they do not face each other in the first direction d1.

[0101] Figure 18 is a schematic cross-sectional view of inductor 1C according to modification 1 of Embodiment 3, showing a cross-section perpendicular to the central axes ca and cb of inductor 1C.

[0102] In the transinductor 1C shown in Figure 18, the opening angles θ of the openings 44 of the second conductor 40a and the second conductor 40b are 180°, and the openings 44 face the same direction (the negative side in the Y-axis direction) (θa = θb). In the transinductor 1C of the modified example 1, the first set of second conductors 40a and the second set of second conductors 40b are arranged such that their respective openings 44 do not face each other in the first direction d1. Figure 18 shows a cross-section of the inductor 1C perpendicular to the central axes ca and cb. In the cross-section of the transinductor 1C perpendicular to the central axes ca and cb, the opening 44 of the second conductor 40a opens with an opening angle θ that is the sum of the opening angles θ / 2 in the clockwise and counterclockwise directions around the central axis ca, starting from the center line La extending from the central axis ca. The opening 44 of the second conductor 40b is opened in the above cross-section of the transinductor 1C with an opening angle θ that is the sum of the opening angles θ / 2 in the clockwise and counterclockwise directions around the central axis ca, from the center line Lb extending from the central axis cb.

[0103] According to the conductor arrangement structure shown in Modification 1, magnetic coupling between two pairs of conductors adjacent to each other in the first direction d1 can be suppressed.

[0104] Figure 19 shows another example of the inductor 1C according to Modification 1 of Embodiment 3.

[0105] In Figure 19, the multiple pairs of conductors include the first pair of first conductors 30a and second conductor 40a, the second pair of first conductors 30b and second conductor 40b, and the third pair of first conductors 30c and second conductor 40c. The three pairs of conductors are spaced apart and arranged adjacent to each other in a first direction d1 along the first surface f1. The rotation angle θc is a counterclockwise angle with the reference axis Rc extending from the central axis cc in the first direction d1 as the reference 0°. Figure 19 shows a cross-section of the inductor 1C perpendicular to the central axes ca, cb, and cc. The opening 44 of the second conductor 40c is opened in a cross-section perpendicular to the central axes ca, cb, and cc of the transinductor 1C with an opening angle θ that is the sum of the opening angles θ / 2 in the clockwise and counterclockwise directions around the central axis cc, from the center line Lc extending from the central axis cc. The opening 44 of the second conductor 40b is opened in the cross-section of the transinductor 1C with an opening angle θ that is the sum of the opening angles θ / 2 in both clockwise and counterclockwise directions around the central axis cb, starting from the center line Lb extending from the central axis cb. The opening 44 of the second conductor 40a is opened in the cross-section of the transinductor 1C with an opening angle θ that is the sum of the opening angles θ / 2 in both clockwise and counterclockwise directions around the central axis ca, starting from the center line La extending from the central axis ca.

[0106] In the transinductor 1C shown in Figure 19, the opening angle θ of each of the openings 44 of the second conductors 40a, 40b, and 40c is 180°, and each of the openings 44 faces the same direction (the negative side in the Y-axis direction) (θa = θb = θc). In this transinductor 1C as well, the first set of second conductors 40a, the second set of second conductors 40b, and the third set of second conductors 40c are arranged such that their respective openings 44 do not face each other in the first direction d1.

[0107] According to the above arrangement of conductors, magnetic coupling between three adjacent pairs of conductors in the first direction d1 can be suppressed.

[0108] [Modification 2 of Embodiment 3] A transformer inductor 1C according to Modification 2 of Embodiment 3 will be described. In this Modification 2 as well, an example will be described in which the openings 44 in the first set and the openings 44 in the second set are arranged so that they do not face each other in the first direction d1.

[0109] Figure 20 is a schematic cross-sectional view of the inductor 1C according to a modified example 2 of Embodiment 3.

[0110] In the transinductor 1C shown in Figure 20, the opening angle θ of the openings 44 of the second conductor 40a and the second conductor 40b is 180°, and the openings 44 face the same direction (the negative side in the X-axis direction) (θa = θb). In the transinductor 1C of the modified example 2, the first set of second conductors 40a and the second set of second conductors 40b are arranged such that their respective openings 44 do not face each other in the first direction d1. In addition, one of the first set of second conductors 40a and the second set of second conductors 40b is placed between the first set of first conductors 30a and the second set of first conductors 30b. In this example, the first set of second conductors 40a is placed between the first set of first conductors 30a and the second set of first conductors 30b.

[0111] According to the conductor arrangement structure shown in Modification 2, magnetic coupling between two pairs of conductors adjacent to each other in the first direction d1 can be suppressed.

[0112] [Modification 3 of Embodiment 3] A transformer inductor 1C according to Modification 3 of Embodiment 3 will be described. In this Modification 3 as well, an example will be described in which the openings 44 in the first set and the openings 44 in the second set are arranged so that they do not face each other in the first direction d1.

[0113] Figure 21 is a schematic cross-sectional view of the inductor 1C according to a modified example 3 of Embodiment 3.

[0114] In the transinductor 1C shown in Figure 21, the opening angles θ of the openings 44 of the second conductor 40a and the second conductor 40b are 180°, and the openings 44 face in different directions. Specifically, the opening 44 of the second conductor 40a faces the negative side in the Y-axis direction, and the opening 44 of the second conductor 40b faces the positive side in the Y-axis direction. In the transinductor 1C of the modified example 3, the first set of second conductors 40a and the second set of second conductors 40b are arranged such that their respective openings 44 do not face each other in the first direction d1.

[0115] Furthermore, in this transinductor 1C, the rotation angle θa of the opening 44 of the second conductor 40a with the central axis ca of the first conductor 30a in the first set as the rotation center, and the rotation angle θb of the opening 44 of the second conductor 40b with the central axis cb of the first conductor 30b in the second set, differ by 90° or more and 180° or less (90° ≤ |θa - θb| ≤ 180°). In this example, the rotation angle θa of the opening 44 of the second conductor 40a in the first set and the rotation angle θb of the opening 44 of the second conductor 40b in the second set differ by 180°.

[0116] According to the conductor arrangement structure shown in Modification 3, magnetic coupling between two pairs of conductors adjacent to each other in the first direction d1 can be suppressed.

[0117] [Modification 4 of Embodiment 3] A transformer inductor 1C according to Modification 4 of Embodiment 3 will be described. In this Modification 4, an example will be described in which the openings 44 in the first set and the openings 44 in the second set face each other.

[0118] Figure 22 is a schematic cross-sectional view of the inductor 1C according to a modified example 4 of Embodiment 3.

[0119] In the transinductor 1C shown in Figure 22, the opening angles θ of the openings 44 of the second conductor 40a and the second conductor 40b are 180°, and the openings 44 face in different directions. Specifically, the opening 44 of the second conductor 40a faces the positive side in the X-axis direction, and the opening 44 of the second conductor 40b faces the negative side in the X-axis direction. In this transinductor 1C, the first pair of second conductors 40a and the second pair of second conductors 40b are arranged so that their respective openings 44 face each other in the first direction d1, satisfying both θa = 0 and θb = 180°. In contrast, as shown in Figures 17, 18, 20, and 21, when the respective openings 44 of the second conductor 40a and the second conductor 40b are not arranged so that they do not face each other in the first direction d1, at least one of θa = 0 and θb = 180° is not satisfied.

[0120] Furthermore, in this transinductor 1C, the rotation angle θa of the opening 44 of the second conductor 40a with the central axis ca of the first conductor 30a in the first set as the center of rotation, and the rotation angle θb of the opening 44 of the second conductor 40b with the central axis cb of the first conductor 30b in the second set as the center of rotation, differ by 90° or more and 180° or less (90° ≤ |θa - θb| ≤ 180°).

[0121] In the transinductor 1C of Modification 4, there is no opposing portion 41 between the first pair of first conductors 30a and the second pair of first conductors 30b, and the volume of the magnetic material 10 between the first pair of first conductors 30a and the second pair of first conductors 30b is larger than in Embodiment 3 and Modifications 1-3. Therefore, in Modification 4, the two pairs of conductors are more easily coupled to each other compared to Embodiment 3 and Modifications 1-3. However, the coupling coefficient of the pair of conductors is at the same level as in Embodiment 3 and Modification 1.

[0122] [Effects, etc.] The effects of the transinductor 1C of Embodiment 3 and Modifications 1 and 4 will be described. Here, the inductance values ​​(self-inductance) of each conductor, the coupling coefficient of a pair of conductors, and the coupling coefficient of two pairs of conductors adjacent in the first direction d1 will be explained in detail.

[0123] Figure 23 shows the coupling coefficient and inductance values ​​when the rotation angles θa, θb, etc. of the opening 44 of the second conductor 40 of the transinductor 1C shown in Embodiment 3 and Modifications 1 and 4 are changed.

[0124] Figure 23(a) shows data for Embodiment 3, (b) shows data for Modification 1, and (c) shows data for Modification 4. Figure 23(d) shows data for Embodiment 3 when the opening angle θ of the opening 44 is 90°, and (e) shows data for Embodiment 3 when the opening angle θ of the opening 44 is 270°.

[0125] Figure 23 shows the inductance values ​​of the first conductor 30a, the second conductor 40a, the first conductor 30b, and the second conductor 40b, corresponding to Figures 23(a) to (e). As shown in this figure, the inductance value can be made 20 nH or more in each of the cases shown in Figures 23(a) to (e). Furthermore, the inductance value can be adjusted by changing the angle of the opening 44 (rotation angle θa, θb, or opening angle θ), as shown in Figures 23(a) to (e).

[0126] Figure 23 also shows the coupling coefficients of the first conductor 30a and the second conductor 40a (a3a4), the first conductor 30b and the second conductor 40b (b3b4), the second conductor 40a and the second conductor 40b (a4b4), and the first conductor 30a and the first conductor 30b (a3b3), as data corresponding to (a) to (e) in Figure 23. It is desirable for the coupling coefficients (a3a4) and (b3b4) of a pair of conductors to be large, and it is desirable for the coupling coefficients (a4b4) and (a3b3) of two pairs of conductors adjacent in the first direction d1 to be small.

[0127] As shown in this figure, in the cases of (a), (b), (c), and (d) in Figure 23, the coupling coefficients (a3a4) and (b3b4) can be set to 0.970 or higher. Also, in the cases of (a), (c), and (e) in Figure 23, the coupling coefficients (a4b4) and (a3b3) can be set to 0.05 or lower.

[0128] Thus, the transinductor 1C shown in Figures 23(a) to (e) can maintain the coupling coefficient of the pair of conductors while suppressing a decrease in the coupling coefficient of the two sets of conductors. Furthermore, as shown in Figures 23(a) to (e), the inductance value of the transinductor 1C can be adjusted by changing the rotation angle θa, θb or the opening angle θ of the opening 44 of the second conductor 40.

[0129] In the embodiment, terms indicating direction such as "top surface" and "bottom surface" refer to relative directions that depend only on the relative positional relationship of the inductor components such as magnetic materials and magnetic cores, and do not indicate absolute directions such as the vertical direction.

[0130] (Summary) Examples of inductors 1, 1A, 1B, and 1C according to one aspect of this disclosure are given below.

[0131] The inductors 1, 1A, 1B, and 1C of Example 1 comprise a magnetic material 10 and a pair of conductors, a first conductor 30 and a second conductor 40. The magnetic material 10 has a first surface f1 and a second surface f2 facing away from each other. The first conductor 30 and the second conductor 40 are provided at least inside the magnetic material 10. The first conductor 30 is cylindrical and is positioned to penetrate the first surface f1 and the second surface f2. An insulating film si is provided on the outer circumference 31d of the first conductor 30. The second conductor 40 is positioned to penetrate the first surface f1 and the second surface f2 and faces at least a portion of the outer circumference 31d of the first conductor 30 via the insulating film si.

[0132] In this way, by arranging the second conductor 40 so as to face the outer circumference 31d of the cylindrical first conductor 30, the coupling coefficient in the inductor can be improved.

[0133] The inductors 1A and 1C in Example 2 are the inductors described in Example 1, wherein the second conductor 40 inside the magnetic material 10 has an arc-shaped cross-section perpendicular to the direction penetrating the first surface f1 and the second surface f2, and may face a part of the outer circumference of the first conductor 30.

[0134] In this way, by making the second conductor 40 arc-shaped, the inductance values ​​of the first conductor 30 and the second conductor 40 can be increased. Furthermore, by changing the arc length of the arc-shaped second conductor 40, for example, the inductance values ​​of the first conductor 30 and the second conductor 40 can be adjusted.

[0135] Inductor 1B in Example 3 is the inductor described in Example 1, and comprises a plurality of pairs of conductors, the plurality of pairs of conductors may be arranged adjacent to each other in a first direction d1 along the first surface f1.

[0136] This configuration allows for space savings compared to, for example, mounting multiple inductors, each comprising a pair of conductors, on a circuit board.

[0137] The inductors 1A and 1C in Example 4 are the inductors described in Example 1, wherein the second conductor 40 has a facing portion 41 that faces the outer circumference 31d of the first conductor 30 and an opening 44 that does not face the first conductor 30, and the opening 44 may be filled with magnetic material 10.

[0138] In this way, by providing an opening 44 in the second conductor 40, the inductance values ​​of the first conductor 30 and the second conductor 40 can be increased. Furthermore, by changing the opening angle θ of the opening 44, for example, the inductance values ​​of the first conductor 30 and the second conductor 40 can be adjusted.

[0139] The inductor 1C in Example 5 is the inductor described in Example 4, and comprises a plurality of pairs of conductors, the plurality of pairs of conductors may be arranged adjacent to each other in a first direction d1 along the first surface f1.

[0140] This configuration allows for space savings compared to, for example, mounting multiple inductors, each comprising a pair of conductors, on a circuit board.

[0141] The inductor 1C in Example 6 is the inductor described in Example 5, wherein the plurality of pairs of conductors include a first pair of first conductors 30a and second conductors 40a, and a second pair of first conductors 30b and second conductors 40b, and the first pair of second conductors 40a and the second pair of second conductors 40b may be arranged such that their respective openings 44 do not face each other in the first direction d1.

[0142] This configuration makes it possible to suppress magnetic coupling between the first conductors 30a and 30b, and also to suppress magnetic coupling between the second conductors 40a and 40b.

[0143] The inductor 1C in Example 7 is the inductor described in Example 6, wherein the rotation angle θa of the opening 44 of the second conductor 40a with the central axis ca of the first conductor 30a in the first set as the rotation center, and the rotation angle θb of the opening 44 of the second conductor 40b with the central axis cb of the first conductor 30b in the second set as the rotation center, may differ by 90° or more and 180° or less.

[0144] This configuration makes it possible to suppress magnetic coupling between the first conductors 30a and 30b, and also to suppress magnetic coupling between the second conductors 40a and 40b.

[0145] The inductor 1C of Example 8 is the inductor described in Example 5, wherein the plurality of pairs of conductors include a first pair of first conductors 30a and second conductors 40a, and a second pair of first conductors 30b and second conductors 40b, and at least one of the first pair of second conductors 40a and the second pair of second conductors 40b may be placed between the first pair of first conductors 30a and the second pair of first conductors 30b.

[0146] This configuration makes it possible to suppress magnetic coupling between the first conductors 30a and 30b, and also to suppress magnetic coupling between the second conductors 40a and 40b.

[0147] The inductors 1, 1A, 1B, and 1C in Example 9 are inductors described in any of Examples 1 to 8, wherein the second conductor 40 has opposing portions 41 arranged perpendicular to the first surface f1 and the second surface f2, and flange-shaped terminal portions 42 connected to each of the two ends 41a of the opposing portions 41, and the first conductor 30 may have protruding portions 35 that protrude outward from the second conductor 40 in a direction perpendicular to the first surface f1 and the second surface f2.

[0148] This configuration makes it possible to mount inductors 1 to 1C on a circuit board or the like.

[0149] The inductors 1, 1A, 1B, and 1C in Example 10 are the inductors described in Example 9, and the protruding portion 35 of the first conductor 30 may have an exposed region 36 in which the outer circumference 31d of the first conductor 30 is exposed.

[0150] This configuration makes it possible to easily mount inductors 1 to 1C onto a circuit board or the like.

[0151] (Other Embodiments, etc.) Although the embodiments and modifications of the inductors, etc. described above have been explained, the disclosure is not limited to the embodiments and modifications described above. Without departing from the spirit of the disclosure, various modifications that a person skilled in the art could conceive of are applied to the embodiments and modifications, as well as other forms constructed by combining some of the components of the embodiments and modifications, are also included in the scope of the disclosure.

[0152] The above example shows the first conductor 30 and the second conductor 40 being arranged so as to penetrate the bottom surface 18 and the top surface 19 of the magnetic material 10, but it is not limited to this. For example, if side surface 11a is the first surface f1 and side surface 11b is the second surface f2, the first conductor 30 and the second conductor 40 may be arranged so as to penetrate side surface 11a and side surface 11b. For example, if side surface 11c is the first surface f1 and side surface 11d is the second surface f2, the first conductor 30 and the second conductor 40 may be arranged so as to penetrate side surface 11c and side surface 11d.

[0153] In the above-described transinductor, an example was shown in which the first conductor 30 functions as a primary coil and the second conductor 40 functions as a secondary coil. Therefore, when comparing the area of ​​the cross-section perpendicular to the direction of current flow, the cross-sectional area of ​​the first conductor 30 is larger than that of the second conductor 40. However, the transinductor is not limited to this, and may be configured in which the second conductor 40 functions as a primary coil and the first conductor 30 functions as a secondary coil. When comparing the area of ​​the cross-section perpendicular to the direction of current flow, the cross-sectional area of ​​the second conductor 40 may be larger than that of the first conductor 30.

[0154] For example, electrical products or circuits using the transinductor described above are also included in this disclosure. Examples of electrical products include power supply devices equipped with the transinductor described above, and various devices equipped with such power supply devices.

[0155] For example, in a multi-phase power supply system where multiple transinductors are used, the electrical circuit having multiple transinductors may be configured such that either the first conductor 30 or the second conductor 40 of each transinductor is placed between the power supply and the load, and either the other first conductor 30 or the second conductor 40 of each transinductor is connected in series with each other.

[0156] The inductor of this disclosure can be widely applied industrially as an inductor implemented in power supply circuits and the like.

[0157] 1, 1A, 1B, 1C Inductor (transformer inductor) 10 Magnetic material 11a, 11b, 11c, 11d Side surface 18 Bottom surface 19 Top surface 30, 30a, 30b, 30c First conductor 31d Outer circumference 35 Protruding part 36, 36a, 36b Exposed area 40, 40a, 40b, 40c Second conductor 41 Opposing part 41a Both ends 42, 42a, 42b Terminal part 44 Opening 70 Substrate module 71 First circuit board 71h, 71ha, 71hb Through-hole 72 Second circuit board 72h, 72ha, 72hb Through-hole 73 Power semiconductor component 75 Motherboard 76 CPU component c, ca, cb, cc Central axis d1 First direction f1 1st surface f2 2nd surface si Insulating film θ Opening angle θa, θb, θc Rotation angle

Claims

1. An inductor comprising a magnetic material and a pair of conductors, a first conductor and a second conductor, wherein the magnetic material has a first surface and a second surface facing away from each other, the first conductor and the second conductor are provided at least inside the magnetic material, the first conductor is cylindrical and positioned to penetrate the first surface and the second surface, an insulating film is provided on the outer circumference of the first conductor, and the second conductor is positioned to penetrate the first surface and the second surface and faces at least a portion of the outer circumference of the first conductor via the insulating film.

2. The inductor according to claim 1, wherein the second conductor inside the magnetic material has an arc-shaped cross-section perpendicular to the direction penetrating the first surface and the second surface, and is facing a part of the outer circumference of the first conductor.

3. The inductor according to claim 1, comprising a plurality of pairs of conductors, wherein the plurality of pairs of conductors are arranged adjacent to each other in a first direction along the first surface.

4. The inductor according to claim 1, wherein the second conductor has a facing portion facing the outer circumference of the first conductor and an opening that does not face the first conductor, and the opening is filled with the magnetic material.

5. The inductor according to claim 4, comprising a plurality of pairs of conductors, wherein the plurality of pairs of conductors are arranged adjacent to each other in a first direction along the first surface.

6. The inductor according to claim 5, wherein the plurality of pairs of conductors comprises a first pair of the first conductor and the second conductor, and a second pair of the first conductor and the second conductor, and the openings of the first pair of the second conductor and the second pair of the second conductor are arranged such that they do not face each other in the first direction.

7. The inductor according to claim 6, wherein the rotation angle of the opening of the second conductor with respect to the central axis of the first conductor in the first set is 90° or more and 180° or less different from the rotation angle of the opening of the second conductor with respect to the central axis of the first conductor in the second set.

8. The inductor according to claim 5, wherein the plurality of pairs of conductors comprises a first pair of the first conductor and the second conductor, and a second pair of the first conductor and the second conductor, and at least one of the second conductor of the first pair and the second conductor of the second pair is disposed between the first pair of the first conductor and the second pair of the first conductor.

9. The inductor according to any one of claims 1 to 3, wherein the second conductor has opposing portions arranged perpendicular to the first and second surfaces, and flange-shaped terminal portions connected to each of the ends of the opposing portions, and the first conductor has protruding portions that protrude outward from the second conductor in a direction perpendicular to the first and second surfaces.

10. The inductor according to claim 9, wherein the protruding portion of the first conductor has an exposed region in which the outer circumference of the first conductor is exposed.

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