Magnetic components and power conversion devices
By using a shielding member to cancel out leakage flux with induced eddy currents, the magnetic component addresses the issue of temperature rise and loss in planar coils, enabling thinner designs without compromising performance.
Patent Information
- Application Number
- JP2021065600
- Authority / Receiving Office
- JP · JP
- Patent Type
- Patents
- Current Assignee / Owner
- Filing Date
- 2021-04-08
- Publication Date
- 2025-08-20
- Estimated Expiration
- 2041-04-08
AI Technical Summary
Existing magnetic components with planar coils face issues of increased temperature and loss due to eddy currents from leakage flux, which cannot be effectively mitigated by existing methods that prevent leakage flux from interlinking with circuit boards, as these methods are incompatible with reducing component thickness.
Incorporating a shielding member made of a conductive material that covers the wiring pattern and is insulated from the core, which induces eddy currents to cancel out leakage flux, thereby reducing the interlinking magnetic flux without increasing the distance between the gap and the wiring pattern.
This approach effectively reduces the temperature rise and loss in the wiring pattern by minimizing leakage flux interlinking, allowing the magnetic component to be thinner while maintaining performance.
Smart Images

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Abstract
Description
[Technical Field]
[0001] The present disclosure relates to magnetic components such as reactors and transformers, and to power conversion devices including the magnetic components. [Background technology]
[0002] For example, magnetic components are mounted in power conversion devices such as DC / DC converters. It is desirable that the magnetic components mounted in power conversion devices be thin and small. In order to make magnetic components thinner and smaller, it is common to configure magnetic components using planar coils, as disclosed in Patent Document 1. In planar coils, windings are formed by wiring patterns on a substrate.
[0003] A gap is sometimes provided in the core of a magnetic component to stabilize the inductance of the magnetic component. While providing a gap in the core can stabilize the inductance, various problems can occur due to leakage flux from the gap. For example, in a magnetic component using a planar coil, when the wiring pattern forming the winding interlinks with the leakage flux from the gap, eddy currents flow in the wiring pattern. When eddy currents flow in the wiring pattern, the temperature of the wiring pattern rises due to Joule heat from the eddy currents. When the temperature of the wiring pattern rises, problems such as an increase in the temperature of the substrate on which the wiring pattern is provided and increased loss in the wiring pattern can occur.
[0004] Patent Document 2 discloses a technique for preventing leakage flux from a transformer mounted in a power conversion device from interlinking with a circuit board mounted with a control circuit that controls the operation of the power conversion device, etc. The technique disclosed in Patent Document 2 prevents leakage flux from the transformer from interlinking with the circuit board by arranging the circuit board so that the axial direction of the primary coil and secondary coil of the transformer is perpendicular to the normal direction of the circuit board. [Prior art documents] [Patent documents]
[0005] [Patent Document 1] Japanese Patent Application Laid-Open No. 2016-213383 [Patent Document 2] Japanese Patent Application Laid-Open No. 2015-61361 Summary of the Invention [Problem to be solved by the invention]
[0006] The technology disclosed in Patent Document 2 prevents leakage flux from interlinking with a circuit board separate from the coil. However, in a planar coil, the winding is formed by the wiring pattern on the board, so the winding, i.e., the coil, and the board are integrated. In a planar coil, the axial direction of the coil and the normal direction of the board cannot be orthogonal to each other. Therefore, the technology disclosed in Patent Document 2 cannot be used to prevent leakage flux from the gap in a planar coil from interlinking with the board. Increasing the distance between the board on which the winding is formed and the gap can reduce leakage flux interlinking with the wiring pattern on the board. However, increasing the distance between the board and the gap is incompatible with reducing the thickness of magnetic components.
[0007] The present disclosure has been made in consideration of the above circumstances, and aims to provide a technology that achieves both thinning of a magnetic component in which a gap is provided in a core and windings are formed by a wiring pattern, and reducing leakage magnetic flux that interlinks with the wiring pattern. [Means for solving the problem]
[0008] A magnetic component according to one aspect of the present disclosure includes a core made of a soft magnetic material, a substrate, and a shielding member that shields magnetism. The core includes a first core material and a second core material disposed across a gap from the first core material. The substrate has a first through hole through which the first core material is inserted. The substrate is provided with a first wiring pattern that winds around the first through hole. The shielding member has a second through hole through which the first core material is inserted. When the substrate is viewed from above, the shielding member covers part or all of the wiring pattern. The shielding member is insulated from the wiring pattern and the core.
[0009] A magnetic component according to one aspect of the present disclosure includes a core made of a soft magnetic material, a substrate, and a shielding member that shields magnetism. The core includes a first core material and a second core material disposed across a gap from the first core material. The substrate has a first through hole through which the first core material is inserted. The substrate has a first wiring layer and a shielding layer. The first wiring device is provided with a first wiring pattern that winds around the first through hole. The shielding layer is insulated from the first wiring layer and is located closer to the gap than the first wiring layer. The shielding member is formed on the shielding layer. The shielding member covers part or all of the wiring pattern when the substrate is viewed from above. The shielding member is insulated from the core.
[0010] A power conversion device according to one aspect of the present disclosure includes the magnetic component according to any one of the above aspects. [Brief explanation of the drawings]
[0011] [Figure 1] FIG. 1 is a perspective view of a magnetic component 1A according to a first embodiment. [Figure 2] FIG. 2 is a cross-sectional view of the magnetic component 1A. [Figure 3] FIG. 2 is an exploded view of the magnetic component 1A. [Figure 4] 10 is a diagram showing an example of a wiring pattern 34 in a magnetic component 1A. FIG. [Figure 5]FIG. 10 is a perspective view of a magnetic component 1B according to a second embodiment. [Figure 6] FIG. 2 is a cross-sectional view of a magnetic component 1B. [Figure 7] FIG. 10 is a perspective view of a magnetic component 1C according to a third embodiment. [Figure 8] FIG. 2 is a cross-sectional view of a magnetic component 1C. [Figure 9] 10 is a diagram showing an example of a wiring pattern 34 in a magnetic component 1C. FIG. [Figure 10] FIG. 10 is a diagram showing an example of a wiring pattern 36 in a magnetic component 1C. [Figure 11] FIG. 10 is a perspective view of a magnetic component 1D according to a fourth embodiment. [Figure 12] FIG. 1 is a cross-sectional view of a magnetic component 1D. [Figure 13] FIG. 10 is a diagram showing an example of a wiring pattern 34 in a magnetic component 1D. [Figure 14] FIG. 10 is a diagram showing an example of a wiring pattern 36 in a magnetic component 1D. [Figure 15] FIG. 10 is a configuration diagram of a magnetic component 1E according to a fifth embodiment. [Figure 16] FIG. 10 is a configuration diagram of a magnetic component 1F according to a sixth embodiment. [Figure 17] FIG. 13 is a configuration diagram of a magnetic component 1G according to a seventh embodiment. DETAILED DESCRIPTION OF THE INVENTION
[0012] 1. First embodiment FIG. 1 is a perspective view of a magnetic component 1A according to a first embodiment of the present disclosure. FIG. 2 is a diagram showing a cross section of the magnetic component 1A taken along line AA in FIG. 1. FIG. 3 is an exploded view of the magnetic component 1A. As shown in FIGS. 1, 2, and 3, the magnetic component 1A includes a core 20, a substrate 30A, and a shield member 40. The magnetic component 1A is a reactor. The magnetic component 1A is mounted on a power conversion device such as a DC / DC converter.
[0013] The core 20 includes a first core material 22 and a second core material 26. The first core material 22 and the second core material 26 are made of a soft magnetic material. In this embodiment, the first core material 22 and the second core material 26 are made of ferrite. As shown in FIG. 2, a cross section of the first core material 22 taken along line AA is E-shaped. As shown in FIGS. 2 and 3, the first core material 22 is formed of a first member 22d formed in a flat plate shape, a second member 22a, a third member 22b, and a fourth member 22c. The dashed dotted lines in FIGS. 2 and 3 indicate the boundaries between the first member 22d and each of the second member 22a, the third member 22b, and the fourth member 22c. As shown in FIGS. 2 and 3, the second member 22a, the third member 22b, and the fourth member 22c are each wall-like members standing up from the first member 22d. 2, the cross section of the second core material 26 taken along the plane of line AA is I-shaped. In other words, the core 20 is a so-called EI core.
[0014] As shown in FIGS. 1, 2, and 3, in this embodiment, the first core material 22 and the second core material 26 are disposed with the plate-shaped members 24a, 24b, and 24c sandwiched between them. Specifically, the plate-shaped member 24a is disposed between the second core material 26 and the second member 22a. The plate-shaped member 24b is disposed between the second core material 26 and the third member 22b. The plate-shaped member 24c is disposed between the second core material 26 and the fourth member 22c. The plate-shaped members 24a, 24b, and 24c are each made of a non-magnetic material. The thicknesses of the plate-shaped members 24a, 24b, and 24c in the direction from the first core material 22 to the second core material 26 are the same. By arranging the first core material 22 and the second core material 26 with the plate-shaped member 24a, the plate-shaped member 24b, and the plate-shaped member 24c sandwiched therebetween, a gap 28 having a constant width is provided in the core 20. By providing the gap 28 having a constant width in the core 20, magnetic saturation is less likely to occur in the core 20, and the inductance of the magnetic component 1A is made constant. The winding of the magnetic component 1A is wound around the third member 22b of the core 20.
[0015] The substrate 30A is, for example, a printed circuit board. As shown in FIG. 3, the substrate 30A is formed in a plate shape. Also, as shown in FIG. 3, the substrate 30A has through holes 32a, 32b, and 32c. The second member 22a of the first core material 22 is inserted through the through hole 32a. The third member 22b of the first core material 22 is inserted through the through hole 32b. The fourth member 22c of the first core material 22 is inserted through the through hole 32c. Also, a wiring pattern 34 is formed on the substrate 30A and wound around the through hole 32b. FIG. 4 is a diagram showing an example of the wiring pattern 34. In FIG. 4, the wiring pattern 34 is indicated by hatching. The wiring pattern 34 functions as a winding that is wound around the third member 22b of the core 20. In other words, the magnetic component 1A is configured using a planar coil.
[0016] The shielding member 40 is a plate-like member made of a conductive material such as copper. As shown in Fig. 3, the shielding member 40 has a through-hole 42. The third member 22b of the first core material 22 is inserted through the through-hole 42.
[0017] As shown in FIG. 1, the shielding member 40 is disposed on top of the substrate 30A. When the substrate 30A on which the shielding member 40 is disposed is viewed from above, the shielding member 40 is disposed so as to cover the entire wiring pattern 34 from the innermost periphery to the outermost periphery. The planar view of the substrate 30A refers to the view of the substrate 30A from the normal direction of the substrate 30A. The shielding member 40 is attached to the substrate 30A using a non-conductive adhesive or the like so as to cover the entire wiring pattern 34. In other words, the shielding member 40 is insulated from the wiring pattern 34.
[0018] In this embodiment, the shield member 40 is made of a conductor, and therefore shields against magnetism. More specifically, when leakage magnetic flux from the gap 28 intersects with the shield member 40, eddy currents are induced in the shield member 40. As shown in FIG. 3 , in this embodiment, when the shield member 40 is viewed from above, the shape of the through hole 42 is a figure without any depressions. A planar view of the shield member 40 refers to a view of the shield member 40 from the normal direction of the shield member 40. A figure without any depressions refers to a figure in which all points on a line segment connecting any two points on the contour of the figure are located within or on the contour of the figure. If the shape of the through hole 42 is a depression when the shield member 40 is viewed from above, eddy currents will not flow across the depression, making it difficult for eddy currents to flow around the through hole 42. As shown in FIG. 3, in this embodiment, when the shield member 40 is viewed in a plan view, the shape of the through hole 42 is a figure without any depressions, so that the induction of eddy currents is not hindered in the surrounding area of the through hole 42 of the shield member 40.
[0019] When leakage flux from the gap 28 interlinks with the shield member 40, eddy currents flowing through the shield member 40 generate magnetic flux in a direction that cancels out the leakage flux. Therefore, in the magnetic component 1A, the leakage flux from the gap 28 and the magnetic flux generated by eddy currents induced in the shield member 40 by the leakage flux interlink with the wiring pattern 34. As a result, the magnetic flux interlinking with the wiring pattern 34 is reduced compared to when the shield member 40 is not present. Eddy currents corresponding to the leakage flux from the gap 28 are induced in the shield member 40, and the temperature of the shield member 40 rises due to Joule heat from these eddy currents. However, the leakage flux interlinking with the shield member 40 is only a portion of the leakage flux from the gap 28, specifically the magnetic flux interlinking with the wiring pattern 34. As a result, the temperature rise in the shield member 40 due to the leakage flux from the gap 28 is limited.
[0020] The magnetic component 1A of this embodiment reduces the magnetic flux linking with the wiring pattern 34 compared to a case where the shield member 40 is not provided. This reduces the temperature rise of the substrate 30A and the increase in loss in the wiring pattern 34 due to leakage flux from the gap 28. The magnetic component 1A of this embodiment, which reduces the effects of leakage flux from the gap 28 by providing the shield member 40, does not need to increase the distance between the gap 28 and the wiring pattern 34. Since it does not need to increase the distance between the gap 28 and the wiring pattern 34, the magnetic component 1A can be made thinner. Thus, this embodiment achieves both a reduction in the thickness of the magnetic component 1A and a reduction in leakage flux linking with the wiring pattern 34. The shield member 40 does not need to be in close contact with the wiring pattern 34. In an embodiment where a gap exists between the shield member 40 and the wiring pattern 34, the wiring pattern 34, which functions as a winding, can be efficiently cooled by flowing a cooling fluid, such as air, through the gap using a cooling fan, for example.
[0021] 2. Second embodiment Fig. 5 is a perspective view of a magnetic component 1B according to a second embodiment of the present disclosure. Fig. 6 is a diagram showing a cross section of the magnetic component 1B taken along line AA in Fig. 5. The magnetic component 1B in this embodiment is a reactor, similar to the magnetic component 1A. The magnetic component 1B is mounted on a power conversion device, similar to the magnetic component 1A.
[0022] The configuration of the magnetic component 1B differs from the configuration of the magnetic component 1A in that the magnetic component 1B includes a substrate 30B instead of the substrate 30A. The substrate 30B is a printed circuit board, like the substrate 30A. The substrate 30B is formed in a plate shape, like the substrate 30A. Although detailed illustrations are omitted in FIGS. 5 and 6 , the substrate 30B has through holes 32a, 32b, and 32c, like the substrate 30A. The substrate 30B is also identical to the substrate 30A in that it includes a wiring pattern 34 that wraps around the through hole 32b. As shown in FIG. 6 , the substrate 30B of this embodiment differs from the substrate 30A in that it includes a wiring layer 310 and a shield layer 320. The wiring pattern 34 is provided on the wiring layer 310. The shield layer 320 is insulated from the wiring layer 310. The shield layer 320 is located closer to the gap 28 than the wiring layer 310. A shielding member 40 is formed on the shielding layer 320 so as to cover the entire wiring pattern 34 when the substrate 30B is viewed from above. When the substrate 30B is viewed from above, this refers to when the substrate 30B is viewed from the normal direction of the substrate 30B.
[0023] The magnetic component 1B of this embodiment also reduces the magnetic flux linking with the wiring pattern 34 compared to when the shield member 40 is not provided, thereby suppressing the temperature rise in the substrate 30B and the increase in loss in the wiring pattern 34 that are caused by the leakage flux from the gap 28. The magnetic component 1B of this embodiment also provides the shield member 40, which reduces the effects of the leakage flux from the gap 28, eliminating the need to increase the distance between the gap 28 and the wiring pattern 34. In this way, this embodiment makes it possible to achieve both a thinner magnetic component 1B and a reduction in the leakage flux linking with the wiring pattern 34.
[0024] 3. Third embodiment Fig. 7 is a perspective view of a magnetic component 1C according to a third embodiment of the present disclosure. Fig. 8 is a diagram showing a cross section of the magnetic component 1C taken along line AA in Fig. 7. The magnetic component 1C in this embodiment is a reactor, similar to the magnetic components 1A and 1B. The magnetic component 1C is mounted on a power conversion device, similar to the magnetic components 1A and 1B.
[0025] The configuration of the magnetic component 1C differs from that of the magnetic component 1B in that it includes a substrate 30C instead of the substrate 30B. Although detailed illustration is omitted in FIGS. 7 and 8, the substrate 30C is the same as the substrate 30B in that it includes through holes 32a, 32b, and 32c. The substrate 30C is also the same as the substrate 30B in that it includes a wiring layer 310 and a shielding layer 320. The substrate 30C includes the wiring layer 310. twist The magnetic component 1C differs from the substrate 30B in that it includes a wiring layer 330 located far from the gap 28 and a wiring pattern 36 electrically connected to the wiring pattern 34 and wound around the through hole 32b, which is formed on the wiring layer 330. In the magnetic component 1C, the wiring patterns 34 and 36 form a winding. FIG. 9 is a diagram showing an example of the wiring pattern 34 in this embodiment. FIG. 10 is a diagram showing an example of the wiring pattern 36 in this embodiment. In this embodiment, the terminal 34b is electrically connected to the terminal 36a, forming a winding extending from the terminal 34a to the terminal 36b. In the winding extending from the terminal 34a to the terminal 36b, the wiring pattern 34 forms the innermost winding, and the wiring pattern 36 forms the outermost winding. As shown in FIGS. 7 and 8, in this embodiment, a shielding member 40 is provided to cover the wiring patterns 34 and 36.
[0026] The magnetic component 1C of this embodiment also reduces the magnetic flux linking with the wiring patterns 34 and 36 compared to when the shield member 40 is not provided, thereby suppressing the temperature rise in the substrate 30C and the increase in loss in the wiring patterns 34 and 36 caused by the leakage flux from the gap 28. The magnetic component 1C of this embodiment also provides the shield member 40, which reduces the effects of the leakage flux from the gap 28, eliminating the need to increase the distance between the gap 28 and the wiring pattern 34. Thus, this embodiment makes it possible to both reduce the thickness of the magnetic component 1C and reduce the leakage flux linking with the wiring patterns 34 and 36.
[0027] 4. Fourth embodiment FIG. 11 is a perspective view of a magnetic component 1D according to a fourth embodiment of the present disclosure. FIG. 12 is a cross-sectional view of the magnetic component 1D taken along line AA in FIG. 11. The configuration of magnetic component 1D differs from that of magnetic component 1C in that it includes substrate 30D instead of substrate 30C. Substrate 30D is identical to substrate 30C in that it includes through holes 32a, 32b, and 32c, wiring layers 310 and 330, and shield layer 320. Substrate 30D differs from substrate 30C in that wiring pattern 34 formed on wiring layer 310 and wiring pattern 36 formed on wiring layer 330 are not electrically connected.
[0028] FIG. 13 is a diagram showing an example of a wiring pattern 34 in this embodiment. FIG. 14 is a diagram showing an example of a wiring pattern 36 in this embodiment. In magnetic component 1D, wiring pattern 34 functions as a first coil. In magnetic component 1D, wiring pattern 36 functions as a second coil separate from the first coil. For example, by using the first coil as a primary coil and the second coil as a secondary coil, magnetic component 1D functions as a transformer. Magnetic component 1D is mounted in a power conversion device in the same way as magnetic components 1A, 1B, and 1C.
[0029] The magnetic component 1D of this embodiment also reduces the magnetic flux linking with the wiring patterns 34 and 36 compared to when the shield member 40 is not provided. This reduces the temperature rise in the substrate 30D and the increase in loss in the wiring patterns 34 and 36 due to leakage flux from the gap 28. The magnetic component 1D of this embodiment also reduces the effects of leakage flux from the gap 28 by providing the shield member 40, eliminating the need to increase the distance between the gap 28 and the wiring pattern 34. Thus, this embodiment achieves both a thin magnetic component 1D and a reduction in leakage flux linking with the wiring patterns 34 and 36. In this embodiment, the wiring pattern 34 functioning as the first coil is formed on a different wiring layer from the wiring pattern 36 functioning as the second coil. However, the wiring patterns 34 and 36 may be provided on a single wiring layer. Specifically, the wiring pattern 34 may be formed on the wiring layer 310 as shown in FIG. 9, and the wiring pattern 36 may be formed on the wiring layer 310 outside the wiring pattern 34 as shown in FIG.
[0030] 5. Fifth embodiment FIG. 15 is a perspective view of a magnetic component 1E according to a fifth embodiment of the present disclosure. Like the magnetic component 1A, the magnetic component 1E in this embodiment is a reactor. Like the magnetic component 1A, the magnetic component 1E is mounted on a power converter. The magnetic component 1E differs from the magnetic component 1A in that it includes a heat sink 60. The heat sink 60 is a heat dissipating body that dissipates heat. The heat sink 60 functions as a cooling means for cooling the shield member 40. The heat sink 60 is fixed to the shield member 40 with a thermally conductive adhesive, solder, or the like. Providing the heat sink 60 enables efficient cooling of the shield member 40, whose temperature rises due to eddy currents flowing in response to leakage magnetic flux from the gap 28. As with the first embodiment, this embodiment also enables the magnetic component 1E to be thinned while reducing leakage magnetic flux interlinking with the wiring pattern 34.
[0031] 6. Sixth embodiment FIG. 16 is a perspective view of a magnetic component 1F according to a sixth embodiment of the present disclosure. The magnetic component 1F according to this embodiment is a reactor, similar to the magnetic component 1A. The magnetic component 1F is mounted on a power converter, similar to the magnetic component 1A. The magnetic component 1F differs from the magnetic component 1A in that it includes a plate-shaped member 70. The plate-shaped member 70 is integrally formed with the shielding member 40 using a conductor or the like. The dashed-dotted line in FIG. 16 indicates the boundary between the shielding member 40 and the plate-shaped member 70. The plate-shaped member 70 is a heat sink that dissipates heat, similar to the heat sink 60 according to the fifth embodiment. The plate-shaped member 70 functions as a cooling means for cooling the shielding member 40. This embodiment also enables efficient cooling of the shielding member 40. Similar to the first embodiment, this embodiment also enables the magnetic component 1F to be thinned while reducing leakage flux interlinked with the wiring pattern 34.
[0032] 7. Seventh embodiment FIG. 17 is a perspective view of a magnetic component 1G according to a seventh embodiment of the present disclosure. The magnetic component 1G in this embodiment is a reactor, similar to the magnetic component 1A. The magnetic component 1G is mounted on a power converter, similar to the magnetic component 1A. In FIG. 17, reference numeral 90 denotes a housing for the power converter in which the magnetic component 1G is mounted. The housing 90 is made of a metal, such as iron or aluminum, i.e., a material with high thermal conductivity. The magnetic component 1G differs from the magnetic component 1A in that it includes a heat conduction path 80 that thermally connects the shielding member 40 and the housing 90. The heat conduction path 80 is formed integrally with the shielding member 40 using a conductor or the like. The dashed-dotted line in FIG. 17 indicates the boundary between the shielding member 40 and the heat conduction path 80. In this embodiment, heat from the shielding member 40 is transferred to the housing 90 via the heat conduction path 80. In this embodiment, the housing 90 functions as a heat sink that dissipates heat, similar to the heat sink 60 in the fifth embodiment and the plate-like member 70 in the sixth embodiment. In this embodiment, the shield member 40 is cooled by allowing heat to be transmitted to the housing 90 via the heat conduction path 80. In other words, the heat conduction path 80 functions as a cooling means for cooling the shield member 40. This embodiment also makes it possible to efficiently cool the shield member 40. Note that this embodiment, like the first embodiment, also makes it possible to achieve both a thinner magnetic component 1G and a reduction in leakage flux interlinked with the wiring pattern 34.
[0033] 8. Transformation The above-described embodiments may be modified as follows: In the following, magnetic component 1A, magnetic component 1B, magnetic component 1C, magnetic component 1D, magnetic component 1E, magnetic component 1F, and magnetic component 1G may be collectively referred to as magnetic component 1.
[0034] (1) In each of the above embodiments, the shield member 40 covers the entire wiring pattern that forms the winding. However, since the effect of leakage magnetic flux from the gap 28 decreases from the innermost periphery to the outermost periphery of the wiring pattern that forms the winding, the shield member 40 may cover only a portion of the wiring pattern 34 that forms the winding, more specifically, a range that includes the innermost periphery but not the outermost periphery.
[0035] (2) The magnetic component 1 may be manufactured or sold as a standalone unit, or a power conversion device including the magnetic component 1 may be manufactured or sold as a standalone unit. Note that the device incorporating the magnetic component 1 is not limited to a power conversion device. The magnetic component 1 may be mounted in an on-board charger. The magnetic component 1 may also be mounted in a charger for charging a home game console, a stationary or portable information terminal, etc., or in a power supply circuit of a home appliance. An on-board charger including the magnetic component 1, a charger including the magnetic component 1, or a power supply circuit including the magnetic component 1 may be manufactured or sold as a standalone unit.
[0036] (3) The material constituting the first core material 22 and the second core material 26 may be a soft magnetic material and may be conductive. An example of a material that is both soft magnetic and conductive is iron. If the first core material 22 and the second core material 26 are made of a conductive material, the core 20 needs to be insulated from the wiring pattern that functions as the winding and the shielding member 40. Therefore, if the first core material 22 and the second core material 26 are made of a conductive material, the surface of the core 20 may be coated with a non-conductive resin or the like.
[0037] (4) In the above embodiments, the shield member 40 is made of a conductor, but it may be made of a soft magnetic material that is magnetized in a direction that cancels out leakage magnetic flux from the gap 28. This is because magnetization of the shield member 40 can reduce leakage magnetic flux that interlinks with the wiring pattern 34. When the shield member 40 is made of a soft magnetic material, the shield member 40 does not need to be conductive.
[0038] 9. Aspects understood from each embodiment and modification The present disclosure is not limited to the above-described embodiments and modifications, and can be realized in various forms without departing from the spirit thereof. For example, the present disclosure can also be realized in the following forms. The technical features in the above embodiments corresponding to the technical features in each form described below can be replaced or combined as appropriate to solve some or all of the problems of the present disclosure or to achieve some or all of the effects of the present disclosure. Furthermore, if a technical feature is not described as essential in this specification, it can be deleted as appropriate.
[0039] Each of magnetic component 1A, magnetic component 1E, magnetic component 1F, and magnetic component 1G according to an embodiment of the present disclosure includes a core 20 made of a soft magnetic material, a substrate 30A, and a shielding member 40 for shielding against magnetism. Core 20 includes a first core material 22 and a second core material 26. Second core material 26 is disposed with a gap 28 between it and first core material 22. Substrate 30A includes a through hole 32b through which a third member 22b of first core material 22 is inserted. Through hole 32b is an example of a first through hole in the present disclosure. Substrate 30A includes a wiring pattern 34 that winds around through hole 32b. Shielding member 40 includes a through hole 42 through which a third member 22b of first core material 22 is inserted. Through hole 42 is an example of a second through hole in the present disclosure. When substrate 30A is viewed from above, shielding member 40 partially or entirely covers wiring pattern 34. The shield member 40 is insulated from the wiring pattern 34 and the core 20. According to the magnetic component 1A, magnetic component 1E, magnetic component 1F, or magnetic component 1G of this aspect, it is possible to reduce the leakage magnetic flux interlinking with the wiring pattern 34 without increasing the distance between the gap 28 and the wiring pattern 34. Therefore, according to this aspect, it is possible to simultaneously reduce the thickness of the magnetic component 1A, 1E, 1F, or 1G and reduce the leakage magnetic flux interlinking with the wiring pattern 34.
[0040] Each of magnetic components 1B, 1C, and 1D according to one embodiment of the present disclosure includes a core 20 made of a soft magnetic material, a substrate 30B, a substrate 30C, or a substrate 30D, and a shielding member 40 for shielding against magnetism. The core 20 includes a first core material 22 and a second core material 26. The second core material 26 is disposed with a gap 28 between it and the first core material 22. The substrates 30B, 30C, and 30D each include a through hole 32b through which the first core material 22 is inserted. The substrates 30B, 30C, and 30D each also include a wiring layer 310 and a shielding layer 320. The wiring layer 310 includes a wiring pattern 34 that wraps around the through hole 32b. The wiring layer 310 is an example of a first wiring layer according to the present disclosure. The wiring pattern 34 is an example of a first wiring pattern according to the present disclosure. The shielding layer 320 is insulated from the wiring layer 310. The shield layer 320 is located closer to the gap 28 than the wiring layer 310. The shield layer 320 is provided with a shield member 40 that covers part or all of the wiring pattern 34 when the substrate 30B, 30C, or 30D is viewed from above. The planar view of the substrate 30C refers to the view of the substrate 30C normal to the substrate 30C. The planar view of the substrate 30D refers to the view of the substrate 30B normal to the substrate 30D. The shield member 40 is insulated from the core 20 and shields against magnetism. The magnetic component 1B, 1C, or 1D of this embodiment can also reduce the leakage flux linking with the wiring pattern 34 without increasing the distance between the gap 28 and the wiring pattern 34. Therefore, this embodiment allows for both a thin magnetic component 1B, 1C, or 1D and a reduction in the leakage flux linking with the wiring pattern 34.
[0041] In an embodiment in which the shield member 40 covers a portion of the wiring pattern 34, the portion of the wiring pattern 34 covered by the shield member 40 need only include the innermost periphery of the wiring pattern 34, and need not include the outermost periphery of the wiring pattern 34. Since the effect of leakage magnetic flux from the gap 28 decreases as you move from the innermost periphery to the outermost periphery of the wiring pattern 34, this embodiment makes it possible to mitigate the effect caused by leakage magnetic flux from the gap 28 interlinking with the wiring pattern 34, without covering the entire wiring pattern 34 with the shield member 40.
[0042] In a more preferred embodiment, the substrate 30C or the substrate 30D has a wiring layer 310 twist The substrate 30C may have a wiring layer 330 located far from the gap 28. The wiring layer 330 is an example of a second wiring layer in the present disclosure. In the substrate 30C of this embodiment, a wiring pattern 36 that is electrically connected to the wiring pattern 34 and that winds around the through hole 32b may be formed on the wiring layer 330. The wiring pattern 36 is an example of a second wiring pattern in the present disclosure. In the substrate 30D of this embodiment, the wiring pattern 36 that winds around the through hole 32b may be formed on the wiring layer 330, and the wiring pattern 34 may be a first coil and the wiring pattern 36 may be a second coil.
[0043] In a more preferred embodiment, the magnetic component 1 may further include a cooling means for cooling the shield member 40. This embodiment enables efficient cooling of the shield member 40, whose temperature rises due to the flow of eddy currents corresponding to leakage magnetic flux from the gap 28. In a more preferred embodiment, when the housing 90 of the device mounting the magnetic component 1 functions as a heat sink, the cooling means may be a heat conduction path 80 that thermally connects the housing 90 and the shield member 40. This embodiment enables the shield member 40 to be cooled using the housing 90 of the device mounting the magnetic component 1 as a heat sink. In another preferred embodiment, the cooling means may be a heat sink that dissipates heat. When the cooling means is a heat sink, a specific example of the cooling means is a heat sink 60 arranged in contact with the shield member 40. This embodiment enables the shield member 40 to be cooled using a heat sink 60 that is later attached to the shield member 40. Furthermore, when the cooling means is a heat sink, another specific example of the cooling means is a plate-like member 70 formed integrally with the shield member 40. According to this aspect, it is possible to form the cooling means for cooling the shield member 40 integrally with the shield member 40 .
[0044] Furthermore, a power conversion device according to one aspect of the present disclosure includes a magnetic component 1, more specifically, any one of magnetic component 1A, magnetic component 1B, magnetic component 1C, magnetic component 1D, magnetic component 1E, magnetic component 1F, and magnetic component 1G. According to this aspect, it is possible to achieve both a reduction in the thickness of a power conversion device including magnetic component 1 in which gap 28 is provided in core 20 and windings are formed by wiring pattern 34, and a reduction in leakage flux in magnetic component 1 that interlinks with wiring pattern 34. [Explanation of symbols]
[0045] 1, 1A, 1B, 1C, 1D, 1E, 1F, 1G...magnetic components, 20...core, 22...first core material, 24a, 24b, 24c...plate-like members, 26...second core material, 30A, 30B, 30C, 30D...substrate, 40...shield member, 34, 36...wiring pattern, 60...heat sink, 70...plate-like member, 80...thermal conduction path, 90...casing.
Claims
1. a core made of a soft magnetic material, the core including a first core material and a second core material disposed with a gap between them; a substrate having a first through hole through which the first core material is inserted and on which a wiring pattern is provided that winds around the first through hole; a shielding member that has a second through hole through which the first core material is inserted, that covers a part or all of the wiring pattern when the substrate is viewed from above, and that shields magnetism; a heat conduction path formed integrally with the shielding member, the shielding member is insulated from the wiring pattern and the core; the heat conduction path is connected to a housing that houses a device in which the magnetic component is mounted, and thermally connects the housing and the shield member; Magnetic parts.
2. 2. The magnetic component according to claim 1, wherein the portion of the wiring pattern includes an innermost periphery of the wiring pattern but does not include an outermost periphery of the wiring pattern.
3. a core made of a soft magnetic material, the core including a first core material and a second core material disposed with a gap between them; a substrate having a first through hole through which the first core material is inserted; a heat conduction path, The substrate is a first wiring layer provided with a first wiring pattern wound around the first through hole; a shield layer insulated from the first wiring layer and positioned closer to the gap than the first wiring layer; a shielding member is formed on the shielding layer, the shielding member covering a part or all of the first wiring pattern when the substrate is viewed from above, the shielding member being insulated from the core, and shielding against magnetism; The heat conduction path is formed integrally with the shielding member, is connected to a housing that houses a device in which the magnetic component is mounted, and thermally connects the housing and the shielding member. Magnetic parts.
4. 4. The magnetic component according to claim 3, wherein the part of the first wiring pattern includes an innermost periphery of the first wiring pattern but does not include an outermost periphery of the first wiring pattern.
5. the substrate has a second wiring layer located farther from the gap than the first wiring layer; a second wiring pattern electrically connected to the first wiring pattern and wound around the first through hole is formed in the second wiring layer; The magnetic component according to claim 3 or 4.
6. the substrate has a second wiring layer located farther from the gap than the first wiring layer; a second wiring pattern wound around the first through hole is formed in the second wiring layer; the first wiring pattern is a first coil, the second wiring pattern is a second coil; The magnetic component according to claim 3 or 4.
7. A magnetic component comprising the magnetic component according to any one of claims 1 to 6. Power conversion device.
Citation Information
Patent Citations
Converter transformer
JP1999186068A
Inductance element with gap
JP1999273974A
Printed coil transformer and printed circuit board
JP2005228758A
Fitting structure of heat generating electronic component
JP2009200219A
Inductor, and switching circuit including the same
JP2015053464A