Power conversion device

Abstract

According to this power conversion device (900), a heat dissipation unit (60) is positioned between a first coil component (701) and a second coil component (702). A housing (10) is thermally connected to the heat dissipation unit (60). The first coil component (701) has a first core (21) and a second core (22). The second coil component (702) has a third core (23) and a fourth core (24). The heat dissipation unit (60) has: a first heat dissipation portion (611) positioned between the first core (21) and the second core (22) and facing a first printed circuit board (31); and a second heat dissipation portion (612) positioned between the third core (23) and the fourth core (24) and facing a second printed circuit board (32).

Description

Power Conversion Device

[0001] The present disclosure relates to a power conversion device.

[0002] In recent years, with the miniaturization of electronic devices, coil components such as transformers and reactors used in power conversion devices have become smaller and thinner. One example of a miniaturized and thinner coil component is a planar coil. As an example of a planar coil, Japanese Patent Laid-Open Publication No. 2020-161799 (Patent Document 1) describes a planar coil component that includes multiple insulating layers, at least two wiring layers, and a magnetic core, with the insulating layers and wiring layers alternately arranged and bonded. The planar coil component has a housing case that abuts against the magnetic core via a heat transfer layer and is arranged to cover the magnetic core.

[0003] Japanese Patent Application Laid-Open No. 2020-161799

[0004] In order to increase the current that can be passed through a power conversion device, multiple planar coils are sometimes combined. When multiple planar coil components are combined, it is necessary to attach a housing case to each of the multiple planar coil components in order to increase the heat dissipation capacity. This can result in the device becoming excessively large.

[0005] The present disclosure has been made in view of the above, and an object of the present disclosure is to provide a power conversion device that can be miniaturized and that can improve the heat dissipation performance of coil components.

[0006] A power conversion device according to the present disclosure includes a first coil component, a second coil component, a heat dissipation portion, and a housing. The second coil component is arranged alongside the first coil component. The heat dissipation portion is located between the first coil component and the second coil component. The housing has a recess that accommodates the first coil component, the second coil component, and the heat dissipation portion, and is thermally connected to the heat dissipation portion. The first coil component includes a first printed circuit board, a first core, and a second core. The first printed circuit board has a first coil pattern. A first through hole is provided in the first printed circuit board. The first core includes a first through portion that passes through the first through hole. The second core includes a second through portion that passes through the first through hole. The first through hole is adjacent to the first coil pattern. The second coil component includes a second printed circuit board, a third core, and a fourth core. The second printed circuit board has a second coil pattern. The second printed circuit board has a second through hole. The third core includes a third through-portion that passes through the second through-hole. The fourth core includes a fourth through-portion that passes through the second through-hole. The second through-hole is adjacent to the second coil pattern. The heat dissipation portion has a first heat dissipation portion located between the first core and the second core and facing the first printed circuit board, and a second heat dissipation portion located between the third core and the fourth core and facing the second printed circuit board.

[0007] According to the power conversion device of the present disclosure, the heat dissipation unit thermally connected to the housing is located between the multiple coil components, thereby effectively cooling the coil components, thereby providing a power conversion device that can be miniaturized and that can improve the heat dissipation performance of the coil components.

[0008] 6 is a circuit diagram showing a configuration of a power conversion device according to embodiment 1. FIG. 7 is an exploded schematic view showing a configuration of a coil device according to embodiment 1. FIG. 8 is an exploded schematic view showing a configuration of a coil section according to embodiment 1. FIG. 9 is an exploded schematic view showing a configuration of a first coil component according to embodiment 1. FIG. 10 is a schematic perspective view showing a configuration of a second printed circuit board according to embodiment 1. FIG. 11 is a schematic plan view showing a configuration of a coil device according to embodiment 1. FIG. 12 is a schematic cross-sectional view taken along line VII-VII of FIG. 6. FIG. 13 is a schematic cross-sectional view taken along line VIII-VIII of FIG. 6. FIG. 14 is a circuit diagram showing an example of connection of coil components. FIG. 15 is a schematic perspective view showing a configuration of a first heat dissipation member according to embodiment 1. FIG. 16 is a schematic cross-sectional view showing a configuration of a first heat dissipation member according to a first modified example of embodiment 1. FIG. 17 is a schematic perspective view showing a configuration of a coil device according to a second modified example of embodiment 1. FIG. 18 is an exploded schematic view showing a configuration of a first coil component according to a third modified example of embodiment 1. FIG. 19 is a schematic plan view showing a configuration of a coil device according to embodiment 2. FIG. 19 is a schematic perspective view showing a configuration of a first member according to embodiment 2. FIG. 19 is a schematic plan view showing a configuration of a coil device according to a modified example of embodiment 2. FIG. 1 is a schematic perspective view showing the configuration of a second member according to a modified example of embodiment 2. FIG. 2 is a schematic plan view showing the configuration of a coil device according to embodiment 3. FIG. 3 is an exploded schematic view showing the configuration of a heat dissipation unit according to embodiment 3. FIG. 4 is a schematic plan view showing the configuration of a coil device according to embodiment 4. FIG. 5 is an exploded schematic view showing the configuration of a heat dissipation unit and a second printed circuit board according to embodiment 4. FIG. 6 is an exploded schematic view showing the configuration of a power conversion device according to embodiment 5. FIG. 7 is a schematic perspective view showing the configuration of a first coil component according to embodiment 5. FIG. 8 is a schematic cross-sectional view showing the configuration of a power conversion device according to a first modified example of embodiment 5. FIG. 9 is a schematic plan view showing the configuration of a power conversion device according to a second modified example of embodiment 5.

[0009] Hereinafter, embodiments of the present disclosure will be described with reference to the drawings. In the following drawings, the same or corresponding parts are designated by the same reference numerals, and the description thereof will not be repeated. Note that the present disclosure is not limited to the following embodiments.

[0010] First Embodiment (Power Conversion Apparatus) First, an example of the circuit operation of a power conversion apparatus 900 according to a first embodiment will be described.

[0011] 1 shows an example of a power conversion device 900. The power conversion device 900 is, for example, an AC-DC conversion device. The power conversion device 900 mainly includes an input terminal 211, a primary rectifier circuit 201, a primary smoothing capacitor 207, an inverter 202, a control circuit 209, a transformer 205, a secondary rectifier circuit 203, a smoothing reactor 206, a secondary smoothing capacitor 208, a photocoupler 204, a secondary voltage / current detection circuit 210, and an output terminal 212.

[0012] An input voltage Vin is applied between the L terminal and the N terminal of the input terminal 211. The input voltage Vin is an AC voltage. The primary rectifier circuit 201 full-wave rectifies the input voltage Vin input to the input terminal 211. The primary rectifier circuit 201 is composed of primary rectifier diodes 201a, 201b, 201c, and 201d.

[0013] The rectified input voltage Vin is smoothed by charging a primary smoothing capacitor 207. This generates a primary smoothed voltage Vc. The primary smoothed voltage Vc is supplied to the inverter 202.

[0014] The inverter 202 converts the supplied primary smoothed voltage Vc into an AC voltage and applies it to the transformer 205. The inverter 202 is composed of primary MOSFETs (Metal-Oxide-Semiconductor Field Effect Transistors) 202a, 202b, 202c, and 202d. The primary MOSFETs 202a, 202b, 202c, and 202d form a bridge circuit.

[0015] The control circuit 209 outputs control signals to the primary MOSFETs 202 a, 202 b, 202 c, and 202 d. The primary MOSFETs 202 a, 202 b, 202 c, and 202 d are switched on and off in sequence in response to the control signals. As a result, the primary smoothed voltage Vc is applied to the transformer 205 as the primary voltage VT.

[0016] The secondary voltage of transformer 205 is full-wave rectified by secondary rectifier circuit 203. Secondary rectifier circuit 203 is composed of secondary rectifier diodes 203a, 203b, 203c, and 203d. The full-wave rectified secondary voltage is smoothed by smoothing reactor 206 and secondary smoothing capacitor 208. As a result, output voltage Vo is output to output terminal 212.

[0017] The secondary voltage / current detection circuit 210 is capable of detecting the output voltage Vo and the output current Io. When the secondary voltage / current detection circuit 210 detects the output voltage Vo and the output current Io, it transmits a feedback signal to the control circuit 209 via the photocoupler 204.

[0018] The control circuit 209 controls the pulse width of the control signal output to the primary MOSFETs 202 a, 202 b, 202 c, and 202 d based on the feedback signal transmitted from the secondary voltage / current detection circuit 210. In this way, the control circuit 209 controls the inverter 202 so that the output voltage Vo and the output current Io approach the target values.

[0019] A terminal 213 is an input terminal of the transformer 205. A terminal 214 is an output terminal of the transformer 205. A terminal 215 is an input terminal of the smoothing reactor 206. A terminal 216 is an output terminal of the smoothing reactor 206. The transformer 205 and the smoothing reactor 206 will be described in detail later.

[0020] (Coil Device) Next, details of the coil device 800 used as the above-mentioned transformer 205 will be described. As shown in Fig. 2, the coil device 800 mainly includes a coil section 700, a housing 10, and a wiring printed circuit board 70. For ease of explanation, the filler 80 is not shown in Fig. 2.

[0021] As shown in FIG. 2 , the housing 10 has a recess 19. The housing 10 has a box-like shape, with the recess 19 provided on one side of a cube or rectangular parallelepiped. The recess 19 has a bottom surface 18 and side wall surfaces 17. The bottom surface 18 is flat. The side wall surfaces 17 are continuous with the bottom surface 18. The side wall surfaces 17 surround the coil portion 700. The material constituting the housing 10 is not particularly limited, but may be a metal with excellent thermal conductivity, such as aluminum. Although not shown, a heat sink or heat dissipation mechanism may be provided on the outer surface of the housing 10.

[0022] If the housing 10 is made of a conductor such as aluminum, it can act as a shield against electromagnetic waves and magnetic flux, thereby reducing the electromagnetic waves and magnetic flux leaking out of the housing 10 from the coil section 700. This prevents malfunction of peripheral devices caused by electromagnetic noise and induction heating caused by magnetic flux interlinking with the conductor.

[0023] The coil part 700 is housed inside the recess 19. The coil part 700 has a first coil component 701, a second coil component 702, a third coil component 703, and a heat dissipation part 60. From another perspective, the heat dissipation part 60, the first coil component 701, the second coil component 702, and the third coil component 703 are each housed inside the recess 19.

[0024] 2 and 3 , the second coil component 702 is arranged side by side with the first coil component 701. The third coil component 703 is arranged side by side with the first coil component 701 and the second coil component 702. The direction in which the first coil component 701, the second coil component 702, and the third coil component 703 are arranged is defined as the first direction 101. The second coil component 702 is arranged between the first coil component 701 and the third coil component 703. Details of the first coil component 701, the second coil component 702, and the third coil component 703 will be described later.

[0025] The heat dissipation unit 60 has, for example, a first heat dissipation member 61 and a second heat dissipation member 62. The first heat dissipation member 61 is disposed between the first coil component 701 and the second coil component 702. The second heat dissipation member 62 is disposed between the second coil component 702 and the third coil component 703. The heat dissipation unit 60 dissipates heat generated in each of the first coil component 701, the second coil component 702, and the third coil component 703.

[0026] The heat dissipation unit 60 is thermally connected to the housing 10. "Two components are thermally connected" means that the two components are in direct surface contact with each other, or that the two components are in indirect surface contact with each other via a substance that has better thermal conductivity than the air.

[0027] The housing 10 and the heat dissipation unit 60 are in contact with or close to each other. When the housing 10 and the heat dissipation unit 60 are close to each other, a filler 80 (described below) is filled between the heat dissipation unit 60 and the housing 10. In this case, the heat dissipation unit 60 and the housing 10 are thermally connected via the filler 80. Note that the portion of the filler 80 located between the heat dissipation unit 60 and the housing 10 may contain air bubbles.

[0028] Similarly, the first coil component 701 is thermally connected to the first heat dissipation member 61, the first heat dissipation member 61 to the second coil component 702, the second coil component 702 to the second heat dissipation member 62, and the second heat dissipation member 62 to the third coil component 703. Therefore, the housing 10 contributes to cooling the coil unit 700.

[0029] 2, the wiring printed circuit board 70 covers, for example, the opening of the recess 19. From another perspective, the wiring printed circuit board 70 and the housing 10 cover the coil portion 700. The wiring printed circuit board 70 is fixed to the housing 10 by, for example, metal fittings, screws, or the like.

[0030] The wiring printed circuit board 70 electrically connects the first coil component 701, the second coil component 702, and the third coil component 703. The wiring printed circuit board 70 is positioned in a second direction 102 with respect to the housing 10. The second direction 102 is a direction perpendicular to the bottom surface 18 of the recess 19. The second direction 102 is the same as, for example, the opening direction of the recess 19. The second direction 102 is perpendicular to the first direction 101.

[0031] A plurality of first connection holes 71 and a plurality of second connection holes 72 are provided on the wiring printed circuit board 70. Each of the plurality of first connection holes 71 penetrates the wiring printed circuit board 70. An input terminal of a coil component, which will be described later, is inserted into each of the plurality of first connection holes 71. Each of the plurality of second connection holes 72 penetrates the wiring printed circuit board 70. An output terminal of a coil component, which will be described later, is inserted into each of the plurality of second connection holes 72.

[0032] <Coil Section> Next, details of the coil section 700 will be described. As shown in Fig. 3, the first coil component 701 has a first core 21, a second core 22, a fifth core 25, a first printed circuit board 31, a first input terminal 41, and a first output terminal 51. The first coil component 701 is, for example, a planar transformer configured with one printed circuit board and three cores.

[0033] 3 , the first core 21, the second core 22, and the fifth core 25 are arranged side by side. The direction in which the first core 21, the second core 22, and the fifth core 25 are arranged is defined as a third direction 103. The third direction 103 is the direction from the first core 21 to the second core 22. The third direction 103 is perpendicular to both the first direction 101 and the second direction 102.

[0034] The second core 22 is spaced apart from the first core 21. The second core 22 is located between the first core 21 and the fifth core 25. The fifth core 25 is spaced apart from each of the first core 21 and the second core 22. The first core 21, the second core 22, and the fifth core 25 each form a closed magnetic circuit. Hereinafter, the first core 21, the second core 22, and the fifth core 25 will also be referred to as the cores of the first coil component 701.

[0035] As shown in FIG. 4 , the first printed circuit board 31 has a first main surface 31a. The first main surface 31a extends along a plane perpendicular to the first direction 101. The first printed circuit board 31 has a first through hole 31i. Specifically, the first through hole 31i is provided in the first main surface 31a. The first through hole 31i has a first through hole portion 31d, a second through hole portion 31e, and a fifth through hole portion 31f. From another perspective, the first through hole portion 31d, the second through hole portion 31e, and the fifth through hole portion 31f are provided in the first main surface 31a. The first through hole portion 31d, the second through hole portion 31e, and the fifth through hole portion 31f are arranged side by side in the third direction 103, for example.

[0036] The first printed circuit board 31 has a first portion 31g and a second portion 31h. The first portion 31g separates the first through hole portion 31d from the second through hole portion 31e. The second portion 31h separates the second through hole portion 31e from the fifth through hole portion 31f.

[0037] The first printed circuit board 31 is, for example, a multi-layer board. The first printed circuit board 31 has a first coil pattern 351. The first coil pattern 351 may be formed on an outer layer of the first printed circuit board 31, may be formed on an inner layer of the first printed circuit board 31, or may be formed on both the outer and inner layers of the first printed circuit board 31. While Fig. 4 shows a configuration in which the first coil pattern 351 is formed on one layer of the first printed circuit board 31, the first coil pattern 351 may be formed on multiple layers of the first printed circuit board 31.

[0038] A copper foil pattern (not shown) may be provided on at least one of the first portion 31g and the second portion 31h of the first printed circuit board 31. For example, if the first printed circuit board 31 is a multilayer board, the copper foil pattern may be formed on an outer layer of the first printed circuit board 31, on an inner layer of the first printed circuit board 31, or on both the outer and inner layers of the first printed circuit board 31.

[0039] The copper foil pattern may or may not be electrically connected to the first coil pattern 351. The copper foil pattern may be in contact with or adjacent to the heat dissipation portion 60. In particular, when the copper foil pattern is formed on the outer layer of the first printed circuit board 31 and is not electrically connected to the first coil pattern 351, the copper foil pattern and the heat dissipation portion 60 may be in contact with each other.

[0040] By providing the copper foil pattern, heat generated by the coil pattern 351 is transferred to the copper foil pattern and dissipated. This increases the heat dissipation area, effectively cooling the coil pattern 351. Furthermore, by bringing the copper foil pattern and the heat dissipation section 60 into contact with or close to each other, the coil pattern 351 can be cooled more effectively.

[0041] The first coil pattern 351 is adjacent to the first through hole 31 i. Specifically, the first coil pattern 351 is adjacent to each of the first through hole portion 31 d, the second through hole portion 31 e, and the fifth through hole portion 31 f. The first coil pattern 351 may surround the first through hole portion 31 d, the second through hole portion 31 e, and the fifth through hole portion 31 f.

[0042] 4 , the first printed circuit board 31 has a third coil pattern 353. The third coil pattern 353 may be formed on an outer layer of the first printed circuit board 31, may be formed on an inner layer of the first printed circuit board 31, or may be formed on both the outer layer and the inner layer of the first printed circuit board 31. The third coil pattern 353 may be formed on multiple layers of the first printed circuit board 31.

[0043] The third coil pattern 353 is adjacent to the first through hole 31i. Specifically, the third coil pattern 353 is adjacent to each of the first through hole portion 31d, the second through hole portion 31e, and the fifth through hole portion 31f. The third coil pattern 353 may surround the first through hole portion 31d, the second through hole portion 31e, and the fifth through hole portion 31f. The first coil pattern 351 and the third coil pattern 353 are magnetically coupled by the first core 21, the second core 22, and the fifth core 25, respectively.

[0044] As shown in Fig. 4, the first input terminal 41 is provided on the first main surface 31a. The first input terminal 41 corresponds to the input terminal 213 of the transformer 205 of the power conversion device 900 shown in Fig. 1. The first input terminal 41 has a first input terminal portion 41a and a second input terminal portion 41b. In other words, the first input terminal 41 is configured by a pair of terminals. The first input terminal portion 41a is electrically connected to the second input terminal portion 41b by the first coil pattern 351.

[0045] An end portion of each of the first input terminal portion 41 a and the second input terminal portion 41 b faces the second direction 102. Each of the first input terminal portion 41 a and the second input terminal portion 41 b protrudes in the second direction 102 relative to the first printed circuit board 31.

[0046] The first output terminal 51 is provided on the first main surface 31a. The first output terminal 51 corresponds to the output terminal 214 of the transformer 205 in the power conversion device 900 shown in FIG. 1. The first output terminal 51 has a first output terminal portion 51a and a second output terminal portion 51b. In other words, the first output terminal 51 is configured by a pair of terminals. Each of the first output terminal portion 51a and the second output terminal portion 51b is electrically connected to, for example, the third coil pattern 353.

[0047] An end portion of each of the first output terminal portion 51 a and the second output terminal portion 51 b faces the second direction 102. Each of the first output terminal portion 51 a and the second output terminal portion 51 b protrudes in the second direction 102 relative to the first printed circuit board 31.

[0048] 2 and 3 , an end of the first input terminal portion 41 a is inserted into one of a plurality of first connection holes 71 of the wiring printed circuit board 70. The first input terminal portion 41 a and the wiring printed circuit board 70 are soldered together. Similarly, the second input terminal portion 41 b and the wiring printed circuit board 70 are soldered together. From another perspective, the first coil pattern 351 of the first printed circuit board 31 and the wiring printed circuit board 70 are electrically connected together by soldering.

[0049] An end of the first output terminal portion 51 a is inserted into one of a plurality of second connection holes 72 of the wiring printed circuit board 70. The first output terminal portion 51 a and the wiring printed circuit board 70 are soldered together. Similarly, the second output terminal portion 51 b and the wiring printed circuit board 70 are soldered together. From another perspective, the third coil pattern 353 of the first printed circuit board 31 and the wiring printed circuit board 70 are electrically connected together by soldering.

[0050] 4, each of the first input terminal portion 41a and the second input terminal portion 41b may have at least one bent portion, which can reduce mechanical stress generated between the first printed circuit board 31 and the wiring printed circuit board 70 when the first input terminal portion 41a and the second input terminal portion 41b are soldered to the wiring printed circuit board 70. The shape of the first output terminal 51 may be the same as the shape of the first input terminal 41.

[0051] As shown in Figures 3 and 4, the first core 21 has a first core member 1a and a second core member 1b. In other words, the first core 21 has a pair of core members. The first core member 1a and the second core member 1b are fixed together by, for example, adhesive tape (not shown). The outer shape of the first core 21 is a rectangular parallelepiped.

[0052] Each of the first core member 1a and the second core member 1b is made of, for example, ferrite. Each of the first core member 1a and the second core member 1b may also be made of a material obtained by sintering iron powder. Specifically, each of the first core member 1a and the second core member 1b may also be made of, for example, Sendust (trademark).

[0053] 4, the first core member 1a has, for example, an E-shape when viewed in the third direction 103. The first core member 1a has a first outer leg portion 81a, a second outer leg portion 81c, a first center leg portion 81b, and a first connecting portion 81d.

[0054] The first outer leg 81a is connected to an end of the first connecting portion 81d. The second outer leg 81c is connected to an end of the first connecting portion 81d opposite to the end to which the first outer leg 81a is connected. The first center leg 81b is connected to the first connecting portion 81d. In the extension direction of the first connecting portion 81d, the first center leg 81b is located between the first outer leg 81a and the second outer leg 81c. The first outer leg 81a, the second outer leg 81c, and the first center leg 81b each extend in a direction perpendicular to the extension direction of the first connecting portion 81d.

[0055] When viewed in the third direction 103, the second core member 1b has, for example, an E-shape. The second core member 1b has a third outer leg 81e, a fourth outer leg 81g, a second center leg 81f, and a second connecting portion 81h.

[0056] The third outer leg 81e is connected to an end of the second connecting portion 81h. The fourth outer leg 81g is connected to an end of the second connecting portion 81h opposite to the end to which the third outer leg 81e is connected. The second center leg 81f is connected to the second connecting portion 81h. In the extension direction of the second connecting portion 81h, the second center leg 81f is located between the third outer leg 81e and the fourth outer leg 81g. The third outer leg 81e, the fourth outer leg 81g, and the second center leg 81f each extend in a direction perpendicular to the extension direction of the second connecting portion 81h.

[0057] The first outer leg 81a, the second outer leg 81c, and the first center leg 81b face the third outer leg 81e, the fourth outer leg 81g, and the second center leg 81f, respectively. The first outer leg 81a and the third outer leg 81e may be in contact with each other. Similarly, the second outer leg 81c and the fourth outer leg 81g may be in contact with each other. The first center leg 81b and the second center leg 81f may be in contact with each other.

[0058] From the viewpoint of adjusting the inductance value of the first core 21 or preventing magnetic saturation of the first core 21, a core gap (not shown) may be provided in at least one of the following locations: between the first outer leg 81a and the third outer leg 81e, between the second outer leg 81c and the fourth outer leg 81g, and between the first middle leg 81b and the second middle leg 81f.

[0059] The core gap may be formed by air or filler 80, or may be formed by a non-magnetic material such as paper or polyester tape. From another perspective, air or filler 80 may be located in at least one of the following spaces: between the first outer leg 81a and the third outer leg 81e; between the second outer leg 81c and the fourth outer leg 81g; and between the first center leg 81b and the second center leg 81f; or a non-magnetic material such as paper or polyester tape may be sandwiched between the first outer leg 81a and the third outer leg 81e;

[0060] The configuration of the second core 22 is substantially the same as the configuration of the first core 21. Specifically, the second core 22 has a third core member 2a and a fourth core member 2b. The third core member 2a corresponds to the first core member 1a. The third core member 2a has a fifth outer leg 82a, a sixth outer leg 82c, a third center leg 82b, and a third connecting portion 82d. The fourth core member 2b corresponds to the second core member 1b. The fourth core member 2b has a seventh outer leg 82e, an eighth outer leg 82g, a fourth center leg 82f, and a fourth connecting portion 82h.

[0061] The configuration of the fifth core 25 is substantially the same as the configuration of the first core 21. Specifically, the fifth core 25 has a ninth core member 5a and a tenth core member 5b. The ninth core member 5a corresponds to the first core member 1a. The ninth core member 5a has a ninth outer leg 85a, a tenth outer leg 85c, a fifth center leg 85b, and a fifth connecting portion 85d. The tenth core member 5b corresponds to the second core member 1b. The tenth core member 5b has an eleventh outer leg 85e, a twelfth outer leg 85g, a sixth center leg 85f, and a sixth connecting portion 85h.

[0062] 3 , the configuration of the second coil component 702 is substantially the same as the configuration of the first coil component 701. Specifically, the second coil component 702 includes a second printed circuit board 32, a third core 23, a fourth core 24, a sixth core 26, a second input terminal 42, and a second output terminal 52.

[0063] 3 and 5 , the second printed circuit board 32 corresponds to the first printed circuit board 31. The second printed circuit board 32 has a second main surface 32a. The second main surface 32a extends along a plane perpendicular to the first direction 101. The first printed circuit board 31 and the second printed circuit board 32 are each arranged so that the second main surface 32a is along a plane parallel to the first main surface 31a. The first printed circuit board 31 and the second printed circuit board 32 may also be arranged so that the first main surface 31a and the second main surface 32a are positioned parallel to each other.

[0064] As shown in FIG. 5 , the second printed circuit board 32 has a second through hole 32i. Specifically, the second through hole 32i is provided in the second main surface 32a. The second through hole 32i has a third through hole portion 32d, a fourth through hole portion 32e, and a sixth through hole portion 32f. From another perspective, the third through hole portion 32d, the fourth through hole portion 32e, and the sixth through hole portion 32f are provided in the second main surface 32a. The third through hole portion 32d, the fourth through hole portion 32e, and the sixth through hole portion 32f correspond to the first through hole portion 31d, the second through hole portion 31e, and the fifth through hole portion 31f, respectively. The second printed circuit board 32 has a third portion 32g and a fourth portion 32h. The third portion 32g and the fourth portion 32h correspond to the first portion 31g and the second portion 31h, respectively.

[0065] The second printed circuit board 32 has a second coil pattern 352. The second coil pattern 352 corresponds to the first coil pattern 351. The second coil pattern 352 is adjacent to the second through hole 32i. Specifically, the second coil pattern 352 is adjacent to each of the third through hole portion 32d, the fourth through hole portion 32e, and the sixth through hole portion 32f. Although not shown in FIG. 5 , the second printed circuit board 32 has a fourth coil pattern 354. The fourth coil pattern 354 corresponds to the third coil pattern 353.

[0066] 3, the third core 23, the fourth core 24, and the sixth core 26 correspond to the first core 21, the second core 22, and the fifth core 25, respectively. The third core 23 is disposed in the first direction 101 relative to the first core 21. The third core 23 faces the first core 21. The third core 23 has a fifth core member 3a and a sixth core member 3b. In this specification, two components facing each other includes a case where a filler 80 is located between the two components.

[0067] The fourth core 24 is disposed in the first direction 101 relative to the second core 22. The fourth core 24 faces the second core 22. The fourth core 24 has a seventh core member 4a and an eighth core member 4b. The sixth core 26 is disposed in the first direction 101 relative to the fifth core 25. The sixth core 26 faces the fifth core 25. The sixth core 26 has an eleventh core member 6a and a twelfth core member 6b. Hereinafter, the third core 23, the fourth core 24, and the sixth core 26 will also be referred to as the cores of the second coil component 702.

[0068] The second input terminal 42 corresponds to the first input terminal 41. The second input terminal 42 has a third input terminal portion 42a and a fourth input terminal portion 42b. The second output terminal 52 corresponds to the first output terminal 51. The second output terminal 52 has a third output terminal portion 52a and a fourth output terminal portion 52b.

[0069] 3 , the configuration of the third coil component 703 is substantially the same as the configuration of the first coil component 701. The third coil component 703 includes a third printed circuit board 33, a seventh core 27, an eighth core 28, a ninth core 29, a third input terminal 43, and a third output terminal 53.

[0070] The third printed circuit board 33 corresponds to the first printed circuit board 31. The seventh core 27, the eighth core 28, and the ninth core 29 correspond to the first core 21, the second core 22, and the fifth core 25, respectively.

[0071] The seventh core 27 is disposed in the first direction 101 relative to the third core 23. The seventh core 27 faces the third core 23. The seventh core 27 has a thirteenth core member 7a and a fourteenth core member 7b. The eighth core 28 is disposed in the first direction 101 relative to the fourth core 24. The eighth core 28 faces the fourth core 24. The eighth core 28 has a fifteenth core member 8a and a sixteenth core member 8b. The ninth core 29 is disposed in the first direction 101 relative to the sixth core 26. The ninth core 29 faces the sixth core 26. The ninth core 29 has a seventeenth core member 9a and an eighteenth core member 9b. Hereinafter, the seventh core 27, the eighth core 28, and the ninth core 29 will also be referred to as cores of the third coil component 703.

[0072] The third input terminal 43 corresponds to the first input terminal 41. The third input terminal 43 has a fifth input terminal portion 43a and a sixth input terminal portion 43b. The third output terminal 53 corresponds to the first output terminal 51. The third output terminal 53 has a fifth output terminal portion 53a and a sixth output terminal portion 53b.

[0073] Fig. 6 shows the configuration of the coil device 800 as viewed in the direction opposite to the second direction 102. For ease of explanation, the wiring printed circuit board 70 is not shown in Fig. 6. As shown in Fig. 6, the coil device 800 has a filler 80. The filler 80 is located inside the recess 19. The filler 80 fills the gaps between the housing 10, the first coil component 701, the second coil component 702, the third coil component 703, the first heat dissipation member 61, and the second heat dissipation member 62.

[0074] The filler 80 covers each of the first printed circuit board 31, the second printed circuit board 32, and the third printed circuit board 33. The filler 80 covers each of the first core 21, the second core 22, the third core 23, the fourth core 24, the fifth core 25, the sixth core 26, the seventh core 27, the eighth core 28, and the ninth core 29. A portion of each of the first input terminal 41, the second input terminal 42, the third input terminal 43, the first output terminal 51, the second output terminal 52, and the third output terminal 53 is exposed from the filler 80.

[0075] The filler 80 covers each of the first heat dissipation member 61 and the second heat dissipation member 62. Air bubbles may be present between the filler 80 and each of the housing 10, the first coil component 701, the second coil component 702, the third coil component 703, and the heat dissipation section 60.

[0076] The filler 80 is made of an insulating material. For example, the filler 80 is made of a resin material with excellent thermal conductivity. Specifically, the filler 80 is made of, for example, a silicone resin.

[0077] The first printed circuit board 31 has a third main surface 31b. The third main surface 31b is opposite the first main surface 31a. The third main surface 31b faces the housing 10. The first through hole portion 31d, the second through hole portion 31e, and the fifth through hole portion 31f (see FIG. 4) each penetrate the first main surface 31a and the third main surface 31b.

[0078] The second printed circuit board 32 has a fourth main surface 32b. The fourth main surface 32b corresponds to the third main surface 31b. The fourth main surface 32b faces the first main surface 31a.

[0079] The third printed circuit board 33 has a fifth main surface 33a and a sixth main surface 33b. The fifth main surface 33a corresponds to the first main surface 31a. The fifth main surface 33a faces the housing 10. The third printed circuit board 33 and the second printed circuit board 32 are each arranged so that the fifth main surface 33a is along a plane parallel to the second main surface 32a. The third printed circuit board 33 and the second printed circuit board 32 may also be arranged so that the fifth main surface 33a and the second main surface 32a are positioned parallel to each other.

[0080] The sixth major surface 33b corresponds to the third major surface 31b and faces the second major surface 32a.

[0081] 7, the first printed circuit board 31 has a first substrate 31c. The first substrate 31c is made of an insulating material. The material of the first substrate 31c is not particularly limited, but is, for example, FR-4 (Flame Retardant type 4) using glass epoxy. The first substrate 31c may also be made of ceramic.

[0082] The first substrate 31c constitutes, for example, the first main surface 31a and the third main surface 31b. The first substrate 31c electrically insulates the first coil pattern 351 and the third coil pattern 353. The first substrate 31c covers, for example, the first coil pattern 351 and the third coil pattern 353. The first coil pattern 351 and the third coil pattern 353 are each electrically insulated from the first core 21, the second core 22, the fifth core 25, the housing 10, and the heat dissipation unit 60 by, for example, the first substrate 31c.

[0083] The first core 21 has a first penetration portion 1c and a first outer peripheral portion 1d. The first penetration portion 1c passes through the first through-hole portion 31d. The first outer peripheral portion 1d surrounds the first printed circuit board 31. The first outer peripheral portion 1d is continuous with the first penetration portion 1c.

[0084] A first core window 1e and a second core window 1f are formed in the first core 21. Each of the first core window 1e and the second core window 1f penetrates the first core 21. Each of the first core window 1e and the second core window 1f is formed between the first penetrating portion 1c and the first outer peripheral portion 1d.

[0085] The first through portion 1c and the first outer peripheral portion 1d are formed by the first core member 1a (see FIG. 4) and the second core member 1b (see FIG. 4). Specifically, the first center leg 81b and the second center leg 81f form the first through portion 1c. When a core gap is provided between the first center leg 81b and the second center leg 81f, the core gap, the first center leg 81b, and the second center leg 81f are collectively referred to as the first through portion 1c.

[0086] The first coil pattern 351 passes through each of the first core window 1 e and the second core window 1 f. From another perspective, the first coil pattern 351 is surrounded by the first core 21. Similarly, the third coil pattern 353 passes through each of the first core window 1 e and the second core window 1 f.

[0087] The second printed circuit board 32 has a second substrate 32c. The second substrate 32c corresponds to the first substrate 31c. The third core 23 has a third penetration portion 3c and a third outer periphery 3d. The third penetration portion 3c corresponds to the first penetration portion 1c. The third outer periphery 3d corresponds to the first outer periphery 1d. The third penetration portion 3c passes through the third through hole portion 32d.

[0088] A fifth core window 3 e and a sixth core window 3 f are formed in the third core 23. The second coil pattern 352 passes through each of the fifth core window 3 e and the sixth core window 3 f. Similarly, the fourth coil pattern 354 passes through each of the fifth core window 3 e and the sixth core window 3 f.

[0089] 7, a seventh through hole portion 33d is provided in the third printed circuit board 33. The seventh through hole portion 33d corresponds to the first through hole portion 31d.

[0090] The third printed circuit board 33 has a third substrate 33c, a fifth coil pattern 355, and a sixth coil pattern 356. The third substrate 33c corresponds to the first substrate 31c. The fifth coil pattern 355 corresponds to the first coil pattern 351. The sixth coil pattern 356 corresponds to the third coil pattern 353.

[0091] The seventh core 27 has a seventh through portion 7c and a seventh outer peripheral portion 7d. The seventh through portion 7c corresponds to the first through portion 1c. The seventh outer peripheral portion 7d corresponds to the first outer peripheral portion 1d. The seventh through portion 7c passes through the seventh through hole portion 33d. The seventh core 27 is formed with a thirteenth core window 7e and a fourteenth core window 7f.

[0092] Each of the first core 21, the third core 23, and the seventh core 27 abuts against, for example, the bottom surface 18 of the recess 19. Each of the first heat dissipation member 61 and the second heat dissipation member 62 abuts against, for example, the bottom surface 18 of the recess 19.

[0093] 8, the second core 22 has a second through portion 2c and a second outer peripheral portion 2d. The second through portion 2c corresponds to the first through portion 1c. The second outer peripheral portion 2d corresponds to the first outer peripheral portion 1d. The second through portion 2c passes through the second through hole portion 31e.

[0094] A third core window 2 e and a fourth core window 2 f are formed in the second core 22. The first coil pattern 351 and the third coil pattern 353 pass through the third core window 2 e and the fourth core window 2 f, respectively. From another perspective, the first coil pattern 351 and the third coil pattern 353 are each surrounded by the second core 22.

[0095] The fourth core 24 has a fourth through portion 4c and a fourth outer peripheral portion 4d. The fourth through portion 4c corresponds to the first through portion 1c. The fourth outer peripheral portion 4d corresponds to the first outer peripheral portion 1d. The fourth through portion 4c passes through the fourth through hole portion 32e.

[0096] A seventh core window 4e and an eighth core window 4f are formed in the fourth core 24. The second coil pattern 352 and the fourth coil pattern 354 pass through the seventh core window 4e and the eighth core window 4f, respectively. From another perspective, the second coil pattern 352 and the fourth coil pattern 354 are each surrounded by the fourth core 24.

[0097] The third printed circuit board 33 has an eighth through hole portion 33e. The eighth through hole portion 33e corresponds to the second through hole portion 31e. The eighth core 28 has an eighth through hole portion 8c and an eighth outer peripheral portion 8d. The eighth through hole portion 8c corresponds to the first through hole portion 1c. The eighth outer peripheral portion 8d corresponds to the first outer peripheral portion 1d. The eighth through hole portion 8c passes through the eighth through hole portion 33e.

[0098] The eighth core 28 has a fifteenth core window 8e and a sixteenth core window 8f formed therein. The fifth coil pattern 355 passes through each of the fifteenth core window 8e and the sixteenth core window 8f. Similarly, the sixth coil pattern 356 passes through each of the fifteenth core window 8e and the sixteenth core window 8f. Each of the second core 22, the fourth core 24, and the eighth core 28 abuts against the bottom surface 18 of the recess 19, for example.

[0099] Although not shown, the fifth core 25 has a fifth through portion and a fifth outer peripheral portion. The fifth through portion corresponds to the first through portion 1c. The fifth outer peripheral portion corresponds to the first outer peripheral portion 1d. The fifth through portion passes through the fifth through hole portion 31f (see FIG. 4). The shapes and dimensions of the first through hole portion 31d, the second through hole portion 31e, and the fifth through hole portion 31f shown in FIG. 4 may be any shapes and dimensions that allow the first through portion 1c, the second through hole portion 2c, and the fifth through hole portion to pass through, respectively.

[0100] Similarly, the sixth core 26 has a sixth penetration portion and a sixth outer peripheral portion. The sixth penetration portion corresponds to the first penetration portion 1c. The sixth outer peripheral portion corresponds to the first outer peripheral portion 1d. The sixth penetration portion passes through a sixth through-hole portion 32f (see FIG. 5).

[0101] Similarly, the ninth core 29 has a ninth through portion and a ninth outer peripheral portion. The ninth through portion corresponds to the first through portion 1c. The ninth outer peripheral portion corresponds to the first outer peripheral portion 1d. A ninth through hole portion is formed in the third printed circuit board 33. The ninth through portion passes through the ninth through hole portion.

[0102] As shown in FIG. 9 , the first input terminal 41, the second input terminal 42, and the third input terminal 43 are electrically connected by a wiring pattern provided on the wiring printed circuit board 70 (see FIG. 2 ). Specifically, for example, the first input terminal portion 41 a, the second input terminal portion 41 b, the third input terminal portion 42 a, the fourth input terminal portion 42 b, the fifth input terminal portion 43 a, and the sixth input terminal portion 43 b are connected in series in this order. In other words, the first coil pattern 351, the second coil pattern 352, and the fifth coil pattern 355 are connected in series, for example. In this case, the first input terminal portion 41 a and the sixth input terminal portion 43 b correspond to the input terminal 213 of the transformer 205 shown in FIG. 1 .

[0103] The first output terminal 51, the second output terminal 52, and the third output terminal 53 are electrically connected by a wiring pattern provided on a wiring printed circuit board 70 (see FIG. 2). Specifically, the first output terminal portion 51a, the third output terminal portion 52a, and the fifth output terminal portion 53a are electrically connected by the wiring printed circuit board 70. Similarly, the second output terminal portion 51b, the fourth output terminal portion 52b, and the sixth output terminal portion 53b are electrically connected by the wiring printed circuit board 70. In other words, the third coil pattern 353, the fourth coil pattern 354, and the sixth coil pattern 356 are connected in parallel, for example.

[0104] Alternatively, the first coil pattern 351, the second coil pattern 352, and the fifth coil pattern 355 may be connected in series, and the third coil pattern 353, the fourth coil pattern 354, and the sixth coil pattern 356 may be connected in series. The method of connecting the coil patterns is not limited to the above-described connection method.

[0105] <Heat Dissipation Section> Next, the heat dissipation section 60 will be described in detail. As shown in Fig. 2, the first heat dissipation member 61 is disposed along the gap between the first coil component 701 and the second coil component 702. Specifically, the first heat dissipation member 61 is located between two adjacent cores of the first coil component 701. The first heat dissipation member 61 is located between two adjacent cores of the second coil component 702.

[0106] 6 , the outer shape of the first heat dissipation member 61 may be line-symmetric when viewed in the direction opposite to the second direction 102 (hereinafter also referred to as a plan view). Specifically, in the plan view, the first heat dissipation member 61 may be line-symmetric with respect to a line perpendicular to the first direction 101. In the plan view, the first heat dissipation member 61 may be line-symmetric with respect to a line parallel to the first direction 101.

[0107] As shown in Figures 6 and 10, the first heat dissipation member 61 has a first main portion 610, a first heat dissipation portion 611, a second heat dissipation portion 612, a third heat dissipation portion 613, a fourth heat dissipation portion 614, a fifth heat dissipation portion 615, a sixth heat dissipation portion 616, a seventh heat dissipation portion 617, and an eighth heat dissipation portion 618.

[0108] The first main portion 610 has a flat plate shape. The first main portion 610 extends along a plane perpendicular to the first direction 101. The first main portion 610 is located between the first coil component 701 and the second coil component 702 in the first direction 101. Specifically, the first main portion 610 is located between the first core 21 and the third core 23, between the second core 22 and the fourth core 24, and between the fifth core 25 and the sixth core 26. The first main portion 610 may be in contact with or close to each of the cores of the first coil component 701 and the second coil component 702.

[0109] The first heat dissipation portion 611 is continuous with the first main portion 610. The first heat dissipation portion 611 extends from the first main portion 610 toward the first printed circuit board 31. In other words, the first heat dissipation portion 611 extends from the first main portion 610 in the direction opposite to the first direction 101.

[0110] The first heat dissipation portion 611 is located between the first core 21 and the second core 22. The first heat dissipation portion 611 faces the first printed circuit board 31. Specifically, the first heat dissipation portion 611 faces the portion of the first main surface 31a that is exposed from the core of the first coil component 701. The first heat dissipation portion 611 faces the first portion 31g (see FIG. 4 ). The first heat dissipation portion 611 may abut or be close to each of the first core 21, the second core 22, and the first printed circuit board 31.

[0111] The second heat dissipation portion 612 is continuous with the first main portion 610. The second heat dissipation portion 612 extends from the first main portion 610 toward the second printed circuit board 32. In other words, the second heat dissipation portion 612 extends from the first main portion 610 in the first direction 101. The first main portion 610 is located between the first heat dissipation portion 611 and the second heat dissipation portion 612.

[0112] The second heat dissipation portion 612 is located between the third core 23 and the fourth core 24. The second heat dissipation portion 612 faces the second printed circuit board 32. Specifically, the second heat dissipation portion 612 faces the portion of the fourth main surface 32b that is exposed from the core of the second coil component 702. The second heat dissipation portion 612 faces the third portion 32g (see FIG. 5 ). The second heat dissipation portion 612 may abut against or be close to each of the third core 23, the fourth core 24, and the second printed circuit board 32.

[0113] The third heat dissipation portion 613 is continuous with the first main portion 610. The third heat dissipation portion 613 extends from the first main portion 610 in the direction opposite to the first direction 101.

[0114] The third heat dissipation portion 613 is located between the second core 22 and the fifth core 25. From another perspective, the second core 22 is located between the first heat dissipation portion 611 and the third heat dissipation portion 613. The third heat dissipation portion 613 faces the first printed circuit board 31. The third heat dissipation portion 613 faces the second portion 31h (see FIG. 4 ). The third heat dissipation portion 613 may abut or be close to each of the second core 22, the fifth core 25, and the first printed circuit board 31.

[0115] The fourth heat dissipation portion 614 is continuous with the first main portion 610. The fourth heat dissipation portion 614 extends from the first main portion 610 in the first direction 101. The first main portion 610 is located between the third heat dissipation portion 613 and the fourth heat dissipation portion 614.

[0116] The fourth heat dissipation portion 614 is located between the fourth core 24 and the sixth core 26. From another perspective, the fourth core is located between the second heat dissipation portion 612 and the fourth heat dissipation portion 614. The fourth heat dissipation portion 614 faces the second printed circuit board 32. The fourth heat dissipation portion 614 faces the fourth portion 32h (see FIG. 5 ). The fourth heat dissipation portion 614 may abut or be adjacent to each of the fourth core 24, the sixth core 26, and the second printed circuit board 32.

[0117] The fifth heat dissipation portion 615 is continuous with the first main portion 610. The fifth heat dissipation portion 615 extends from the first main portion 610 in the direction opposite to the first direction 101. The fifth heat dissipation portion 615 is located opposite the first heat dissipation portion 611 with respect to the first core 21. From another perspective, the first core 21 is located between the fifth heat dissipation portion 615 and the first heat dissipation portion 611.

[0118] The fifth heat dissipation portion 615 faces the first printed circuit board 31. The fifth heat dissipation portion 615 may be in contact with or adjacent to each of the first core 21 and the first printed circuit board 31.

[0119] The sixth heat dissipation portion 616 is continuous with the first main portion 610. The sixth heat dissipation portion 616 extends from the first main portion 610 in the first direction 101. The sixth heat dissipation portion 616 is located opposite the second heat dissipation portion 612 with respect to the third core 23. From another perspective, the third core 23 is located between the sixth heat dissipation portion 616 and the second heat dissipation portion 612.

[0120] The sixth heat dissipation portion 616 faces the second printed circuit board 32. The sixth heat dissipation portion 616 may be in contact with or adjacent to each of the third core 23 and the second printed circuit board 32.

[0121] The seventh heat dissipation portion 617 is continuous with the first main portion 610. The seventh heat dissipation portion 617 extends from the first main portion 610 in the direction opposite to the first direction 101. The seventh heat dissipation portion 617 is located opposite the third heat dissipation portion 613 with respect to the fifth core 25. From another perspective, the fifth core 25 is located between the seventh heat dissipation portion 617 and the third heat dissipation portion 613.

[0122] The seventh heat dissipation portion 617 faces the first printed circuit board 31. The seventh heat dissipation portion 617 may be in contact with or close to each of the fifth core 25 and the first printed circuit board 31.

[0123] The eighth heat dissipation portion 618 is continuous with the first main portion 610. The eighth heat dissipation portion 618 extends from the first main portion 610 in the first direction 101. The eighth heat dissipation portion 618 is located opposite the fourth heat dissipation portion 614 with respect to the sixth core 26. From another perspective, the sixth core 26 is located between the eighth heat dissipation portion 618 and the fourth heat dissipation portion 614.

[0124] The eighth heat dissipation portion 618 faces the second printed circuit board 32. The eighth heat dissipation portion 618 may be in contact with or adjacent to each of the sixth core 26 and the second printed circuit board 32.

[0125] 2, the second heat dissipation member 62 is disposed between the second coil component 702 and the third coil component 703. The second heat dissipation member 62 is disposed along the gap between the second coil component 702 and the third coil component 703. Specifically, as shown in FIG. 6, a portion of the second heat dissipation member 62 is located between two adjacent cores of the second coil component 702. A portion of the second heat dissipation member 62 is located between two adjacent cores of the third coil component 703.

[0126] The shape of the second heat dissipation member 62 is the same as the shape of the first heat dissipation member 61. From another perspective, the heat dissipation unit 60 is composed of multiple parts with the same shape. The second heat dissipation member 62 has a second main portion 620, a ninth heat dissipation portion 621, a tenth heat dissipation portion 622, an eleventh heat dissipation portion 623, a twelfth heat dissipation portion 624, a thirteenth heat dissipation portion 625, a fourteenth heat dissipation portion 626, a fifteenth heat dissipation portion 627, and a sixteenth heat dissipation portion 628.

[0127] The second main portion 620 corresponds to the first main portion 610. The ninth heat dissipation portion 621, the tenth heat dissipation portion 622, the eleventh heat dissipation portion 623, and the twelfth heat dissipation portion 624 correspond to the first heat dissipation portion 611, the second heat dissipation portion 612, the third heat dissipation portion 613, and the fourth heat dissipation portion 614, respectively. The thirteenth heat dissipation portion 625, the fourteenth heat dissipation portion 626, the fifteenth heat dissipation portion 627, and the sixteenth heat dissipation portion 628 correspond to the fifth heat dissipation portion 615, the sixth heat dissipation portion 616, the seventh heat dissipation portion 617, and the eighth heat dissipation portion 618, respectively.

[0128] 7 and 8 , the height of the first heat dissipation member 61 in the second direction 102 is equal to or less than the height of each of the cores of the first coil component 701 and the second coil component 702 in the second direction 102. This prevents physical contact between the first heat dissipation member 61 and the wiring printed circuit board 70 when the first coil component 701 and the second coil component 702 are electrically connected to the wiring printed circuit board 70.

[0129] Similarly, the height of the second heat dissipation member 62 in the second direction 102 is equal to or less than the height of the core of the second coil component 702 and the core of the third coil component 703 in the second direction 102. The heights of the first heat dissipation member 61 and the second heat dissipation member 62 are not limited to the above heights. The heights of the first heat dissipation member 61 and the second heat dissipation member 62 may be greater than the heights of the core of the first coil component 701 and the core of the second coil component 702. At least one of the first heat dissipation member 61 and the second heat dissipation member 62 may abut a portion of the wiring printed circuit board 70 that is separated from the wiring pattern of the wiring printed circuit board 70. In this case, positioning of the wiring printed circuit board 70 in the second direction 102 is facilitated.

[0130] The heat dissipation unit 60 is made of a metal with a relatively high thermal conductivity. Specifically, the thermal conductivity of the material making up the heat dissipation unit 60 is higher than the thermal conductivity of the material making up the core (first core 21, etc.) of the coil unit 700. The material making up the heat dissipation unit 60 is not particularly limited, but may be aluminum, for example. Examples of methods for manufacturing the first heat dissipation member 61 and the second heat dissipation member 62 include extrusion, drawing, cutting, and aluminum die casting. The methods for manufacturing the first heat dissipation member 61 and the second heat dissipation member 62 are not limited to the above methods.

[0131] (Method of Manufacturing Coil Device) Next, a method of manufacturing the coil device 800 according to the first embodiment will be described.

[0132] First, the coil part 700 is assembled. Specifically, the first heat dissipation member 61 is disposed between the first coil component 701 and the second coil component 702. The second heat dissipation member 62 is disposed between the second coil component 702 and the third coil component 703.

[0133] The coil unit 700 is housed inside the recess 19 of the housing 10. For example, as shown in FIG. 2 , the first printed circuit board 31, the second printed circuit board 32, and the third printed circuit board 33 are each disposed perpendicular to the bottom surface 18 of the recess 19.

[0134] The cores of the first coil component 701, the second coil component 702, and the third coil component 703 abut against the bottom surface 18, allowing each of the first coil component 701, the second coil component 702, and the third coil component 703 to stand on their own. Therefore, members for fixing the first coil component 701, the second coil component 702, and the third coil component 703 are not required. Specifically, for example, a housing case and fixing members attached to the coil components are not required. This allows the coil device 800 and the power conversion device 900 to be made smaller. Furthermore, the time required to arrange the members for fixing the coil components is not required. This shortens the time required to manufacture the coil device 800. As a result, the manufacturing costs of the coil device 800 and the power conversion device 900 can be reduced.

[0135] The first heat dissipation member 61 and the second heat dissipation member 62 each abut against the bottom surface 18, allowing each to stand on its own. This eliminates the need for a member to secure the heat dissipation unit 60. This allows the coil device 800 and the power conversion device 900 to be made smaller. Furthermore, this eliminates the need for time to arrange a member to secure the heat dissipation unit 60. This allows the time required to manufacture the coil device 800 to be shortened. As a result, the manufacturing costs of the coil device 800 and the power conversion device 900 can be reduced.

[0136] The position of the coil unit 700 is adjusted so that the input terminal and output terminal of the coil unit 700 can be inserted into the first connection hole 71 and the second connection hole 72 of the wiring printed circuit board 70, respectively. The filler 80 is filled into the interior of the recess 19. This fixes the coil unit 700 in place.

[0137] The manufacturing method of the housing 10 is not particularly limited, but examples thereof include sheet metal drawing, sheet metal bending, aluminum die casting, etc. When the housing 10 is manufactured using sheet metal bending, voids are formed at the corners of the housing 10. Therefore, the voids may be sealed using tape, caulking material, or the like to prevent the filler 80 from leaking from the voids.

[0138] The housing 10 and the heat dissipation unit 60 may be integrally molded. For example, the housing 10 and the heat dissipation unit 60 may be integrally molded using aluminum die casting. By integrally molding the housing 10 and the heat dissipation unit 60, the position of the heat dissipation unit 60 relative to the housing 10 is fixed. This eliminates the need to position the heat dissipation unit 60, thereby reducing the time required to assemble the coil device 800. Furthermore, by integrally molding the housing 10 and the heat dissipation unit 60, contact thermal resistance between the heat dissipation unit 60 and the housing 10 is eliminated, improving the heat dissipation performance from the heat dissipation unit 60 to the housing 10.

[0139] The coil unit 700 and the wiring printed circuit board 70 are connected by soldering or the like. Specifically, the first input terminal 41, the second input terminal 42, the third input terminal 43, the first output terminal 51, the second output terminal 52, and the third output terminal 53 are each connected by soldering or the like to the wiring printed circuit board 70. In this manner, the coil device 800 is manufactured.

[0140] Next, the effects of the power conversion device 900 according to the first embodiment will be described. In the following, with respect to multiple elements with similar configurations (for example, the first coil component 701, the second coil component 702, and the third coil component 703), only the case where the power conversion device 900 includes the minimum number of such elements required to achieve the desired effect will be described. Specifically, for example, when describing the effects of the power conversion device 900 including the first coil component 701 and the second coil component 702, a description of the effects of the power conversion device 900 further including the third coil component 703 will be omitted. When the power conversion device 900 further includes the third coil component 703, the same effects as those achieved when the power conversion device 900 includes the first coil component 701 and the second coil component 702 are achieved.

[0141] The power conversion device 900 according to the first embodiment includes a first coil component 701, a second coil component 702, a heat dissipation unit 60, and a housing 10. The heat dissipation unit 60 is located between the first coil component 701 and the second coil component 702. The housing 10 is thermally connected to the heat dissipation unit 60. This allows the power conversion device 900 to be more compact than when a housing case is attached to each of the multiple coil components. Furthermore, since the heat dissipation unit 60, which is thermally connected to the housing 10, is located between the multiple coil components, the coil components can be cooled effectively. As a result, the heat dissipation performance of the coil components can be improved, and the power conversion device 900 can be made more compact.

[0142] According to the power conversion device 900 of the first embodiment, the first coil component 701 includes a first printed circuit board 31, a first core 21, and a second core 22. The first printed circuit board 31 includes a first coil pattern 351. The first printed circuit board 31 includes a first through hole 31d and a second through hole 31e. The first core 21 includes a first through hole 1c that passes through the first through hole 31d. The second core 22 includes a second through hole 2c that passes through the second through hole 31e. Each of the first through hole 31d and the second through hole 31e is adjacent to the first coil pattern 351. Therefore, compared to combining two coil components each having only one core, the area of ​​the printed circuit board exposed from the core can be reduced. This allows the coil device 800 to be miniaturized.

[0143] According to the coil device 800 according to the first embodiment, the heat dissipation unit 60 has a first heat dissipation portion 611 and a second heat dissipation portion 612. The first heat dissipation portion 611 is located between the first core 21 and the second core 22 and faces the first printed circuit board 31. The second heat dissipation portion 612 is located between the third core 23 and the fourth core 24 and faces the second printed circuit board 32. Therefore, the heat dissipation unit 60 can effectively cool each of the first printed circuit board 31 and the second printed circuit board 32. This makes it possible to prevent the occurrence of heat spots on each of the first printed circuit board 31 and the second printed circuit board 32.

[0144] As the input voltage to the coil components decreases, the insulation distance and creepage distance that must be considered become shorter. According to the power conversion device 900 of embodiment 1, when the input terminal (first input terminal 41) of the first coil component 701 and the input terminal (second input terminal 42) of the second coil component 702 are connected in series, the voltage input to each of the first coil component 701 and the second coil component 702 becomes smaller than the primary voltage VT applied to the coil device 800. This reduces the insulation distance and creepage distance that must be considered for each of the first coil component 701 and the second coil component 702. This reduces the space and area required to electrically insulate each of the first coil component 701 and the second coil component 702 from other components. Therefore, the power conversion device 900 can be made smaller than when a transformer 205 with the same specifications (e.g., inductance value) is configured using a single coil component.

[0145] Typically, the thermal conductivity of the material that makes up the core of a planar transformer is relatively low. Specifically, the thermal conductivity of ferrite, one example of a material that makes up the core, is approximately 1 to 5 W / (m·K). On the other hand, the thermal conductivity of aluminum is 236 W / (m·K). Therefore, in planar transformers, heat is not easily dissipated in the portion of the printed circuit board that is covered by the core. This makes it easy for heat spots to occur on the printed circuit board.

[0146] According to the power conversion device 900 of the first embodiment, the filler 80 is located in the recess 19. The filler 80 fills the gaps between the housing 10, the first coil component 701, the second coil component 702, and the heat dissipation unit 60. Therefore, the first coil component 701, the second coil component 702, and the heat dissipation unit 60 can each be fixed to the housing 10 by the filler 80. This makes it possible to suppress vibration of the first coil component 701, the second coil component 702, and the heat dissipation unit 60. Therefore, the vibration resistance of the power conversion device 900 is improved.

[0147] Furthermore, the filler 80 is made of an insulating material, which allows the housing 10, the first coil component 701, the second coil component 702, and the heat dissipation section 60 to be electrically insulated from each other more reliably.

[0148] Each of the first printed circuit board 31, the second printed circuit board 32, and the third printed circuit board 33 is covered with the filler 80. This makes it possible to prevent each of the first printed circuit board 31, the second printed circuit board 32, and the third printed circuit board 33 from becoming dirty or absorbing moisture due to the usage environment of the power conversion device 900. This makes it possible to prevent deterioration of the insulation performance of each of the first printed circuit board 31, the second printed circuit board 32, and the third printed circuit board 33.

[0149] Furthermore, by covering each of the first printed circuit board 31, the second printed circuit board 32, and the third printed circuit board 33 with the filler 80, the degree of contamination (Comparative Tracking Index (CTI)) that must be considered for each of the first printed circuit board 31, the second printed circuit board 32, and the third printed circuit board 33 can be reduced. This reduces the insulation distance and creepage distance that must be considered for each of the first printed circuit board 31, the second printed circuit board 32, and the third printed circuit board 33. This allows each of the first printed circuit board 31, the second printed circuit board 32, and the third printed circuit board 33 to be reduced in size. As a result, the power conversion device 900 can be reduced in size.

[0150] The number of coil components and the number of coil component cores may be changed depending on the magnitude of the power and current supplied to the coil device 800. According to the power conversion device 900 of embodiment 1, the heat dissipation unit 60 is composed of multiple components having the same shape. From another perspective, the shapes of the components constituting the heat dissipation unit 60 are standardized to a certain extent. Therefore, by changing the number of components of the heat dissipation unit 60 depending on the number of coil components and the number of coil component cores, the heat dissipation performance of the coil device 800 can be appropriately changed. Therefore, it is not necessary to re-produce molds for the components of the heat dissipation unit 60 depending on the specifications of the coil device 800. This reduces the manufacturing cost of the coil device 800. The heat dissipation unit 60 may be composed of a component obtained by cutting off a part of a heat dissipation member having the same shape as the first heat dissipation member 61.

[0151] Since the heat dissipation section 60 is made up of a plurality of parts having the same shape, it is possible to standardize part of the process when assembling the coil device 800. This allows the manufacturing cost of the coil device 800 to be reduced.

[0152] According to the power conversion device 900 of the first embodiment, the first heat dissipation member 61 and the second heat dissipation member 62, each made of a conductor such as aluminum, are disposed between the first coil component 701, the second coil component 702, and the third coil component 703. This makes it possible to prevent leakage flux radiated from each of the first coil component 701, the second coil component 702, and the third coil component 703 from interlinking with the conductors included in each of the first coil component 701, the second coil component 702, and the third coil component 703. This makes it possible to prevent each of the first coil component 701, the second coil component 702, and the third coil component 703 from generating heat due to induction heating.

[0153] Modification of First Embodiment Although the configuration in which the coil device 800 is the transformer 205 has been described above, the coil device 800 may also be a reactor. From another perspective, each of the first coil component 701, the second coil component 702, and the third coil component 703 may also be a reactor. The coil device 800 may also be used as the smoothing reactor 206 (see FIG. 1 ).

[0154] When the first coil component 701 is a reactor, the first input terminal 41 may be configured by one input terminal portion, and the first output terminal 51 may be configured by one output terminal portion. Each of the first input terminal 41 and the first output terminal 51 is electrically connected to the first coil pattern 351. The first coil component 701 does not need to have the third coil pattern 353.

[0155] When the first coil component 701 is a reactor, the first input terminal 41 corresponds to the input terminal 215 of the smoothing reactor 206 shown in Fig. 1. The first output terminal 51 corresponds to the output terminal 216 of the smoothing reactor 206 shown in Fig. 1.

[0156] In the above description, the first core 21 is composed of two E-shaped core members, but the first core 21 may be composed of, for example, an E-shaped core member and an I-shaped core member. From another perspective, for example, the first core member 1a may be composed of only the first connecting portion 81d.

[0157] In the above description, the recess 19 of the housing 10 is open in the second direction 102, but the recess 19 may be open in the first direction 101 or in the third direction 103. The recess 19 need not be open in the direction of gravity.

[0158] In the above, the first printed circuit board 31, the second printed circuit board 32, and the third printed circuit board 33 are each arranged perpendicular to the bottom surface 18 of the recess 19, but the orientation of the first printed circuit board 31, the second printed circuit board 32, and the third printed circuit board 33 is not limited to the above orientation. Specifically, the coil unit 700 may be arranged so that the direction in which the first coil component 701, the second coil component 702, and the third coil component 703 are aligned (first direction 101) is perpendicular to the bottom surface 18. The coil unit 700 may be arranged so that the direction in which the first core 21, the second core 22, and the fifth core 25 are aligned (third direction 103) is perpendicular to the bottom surface 18.

[0159] The shapes of the first input terminal 41, the second input terminal 42, the third input terminal 43, the first output terminal 51, the second output terminal 52, and the third output terminal 53 are not limited to those described above. For example, the first input terminal 41 may be a connector. A connector corresponding to the first input terminal 41 may be provided on the wiring printed circuit board 70. The first coil pattern 351 and the wiring printed circuit board 70 may be electrically connected by mating the first input terminal 41 with the connector of the wiring printed circuit board 70.

[0160] The method of electrically connecting the first coil component 701, the second coil component 702, and the third coil component 703 is not limited to the method using the wiring printed circuit board 70. Specifically, the first input terminal 41 may be a screw terminal. A cable, a bus bar, or the like may be fixed to the first input terminal 41 using a screw. Similarly, a cable, a bus bar, or the like may be fixed to each of the second input terminal 42 and the third input terminal 43. In this way, the first coil component 701, the second coil component 702, and the third coil component 703 may be electrically connected.

[0161] The first coil pattern 351 may be exposed from the first substrate 31c to the outside of the first printed circuit board 31. In this case, the first coil pattern 351 may be electrically insulated from the core of the first coil component 701, the heat dissipation unit 60, and the housing 10 by an electrical insulating tape such as polyimide tape.

[0162] A spacer made of resin, which is an insulating material, may be disposed between the first printed circuit board 31 and the core of the first coil component 701. This prevents the first printed circuit board 31 and the core of the first coil component 701 from coming into physical contact with each other. Note that the configuration for electrically insulating each of the first coil pattern 351 and the third coil pattern 353 from the core of the first coil component 701 is not limited to the above configuration.

[0163] The configuration for electrically insulating the coil component and the heat dissipation member 60 is not limited to the above configuration. The cross section shown in Fig. 11 corresponds to the cross section taken along line XI-XI in Fig. 6. For ease of explanation, Fig. 11 only shows the first printed circuit board 31, the second printed circuit board 32, and the first heat dissipation member 61.

[0164] 11 , the first heat dissipation member 61 may have a first protrusion 691 and a second protrusion 692. The first protrusion 691 protrudes from the first heat dissipation portion 611 in the direction opposite to the first direction 101. In the second direction 102, the length of the first protrusion 691 is shorter than the length of the first heat dissipation portion 611. The second protrusion 692 protrudes from the second heat dissipation portion 612 in the first direction 101. In the second direction 102, the length of the second protrusion 692 is shorter than the length of the second heat dissipation portion 612.

[0165] The first protrusion 691 abuts against the first printed circuit board 31. Specifically, the first protrusion 691 abuts against the first base material 31c and is spaced apart from the first coil pattern 351. This allows the distance between the first coil pattern 351 and the first heat dissipation portion 611 to be sufficiently long. Therefore, the first coil pattern 351 and the first heat dissipation portion 611 can be electrically insulated from each other. Similarly, the second protrusion 692 abuts against the second printed circuit board 32.

[0166] An electronic component, a spacer, or the like that is not electrically connected to the first coil pattern 351 may be disposed on the first substrate 31c. The electronic component, the spacer, or the like may be brought into contact with the first heat dissipation member 61, thereby making the distance between the first coil pattern 351 and the first heat dissipation member 61 sufficiently long.

[0167] In the above description, the first printed circuit board 31 is configured as a multilayer board having two or more pattern layers, but the first printed circuit board 31 is not limited to a multilayer board. Specifically, the first printed circuit board 31 may be a single-sided board or a double-sided board.

[0168] As shown in FIG. 12 , an injection port 340 may be provided in the wiring printed circuit board 70. The injection port 340 may be a notch or a through-hole. When manufacturing the coil device 800, the filler 80 may be filled into the interior of the recess 19 through the injection port 340. In this case, before filling the interior of the recess 19 with the filler 80, the coil unit 700 and the wiring printed circuit board 70 can be connected by soldering or the like. The injection port 340 may be provided in the housing 10.

[0169] As another example of a method for manufacturing coil device 800, after filling recess 19 of housing 10 with filler 80, first coil component 701, second coil component 702, third coil component 703, first heat dissipation member 61, and second heat dissipation member 62 may be inserted into recess 19 in this order, thereby storing coil unit 700 inside recess 19. Note that the method for manufacturing coil device 800 is not limited to the method shown in the above example.

[0170] The filler 80 does not have to completely fill the recess 19 of the housing 10. It is sufficient that the filler 80 is filled so that each of the first printed circuit board 31, the second printed circuit board 32, and the third printed circuit board 33 is covered with the filler 80. In other words, a space may be provided between the filler 80 and the wiring printed circuit board 70. This allows the volume of the filler 80 in the coil device 800 to be reduced. Therefore, the manufacturing cost of the coil device 800 can be reduced. As a result, the manufacturing cost of the power conversion device 900 can be reduced. In particular, when the filler 80 is made of a resin with excellent thermal conductivity, which is generally expensive, the manufacturing cost of the power conversion device 900 can be effectively reduced.

[0171] The housing 10 may have a protrusion shaped to follow the outer shape of the coil portion 700. The protrusion is continuous with the side wall surface 17 of the recess 19. This allows the volume of the recess 19 to be reduced. Therefore, the volume of the filler 80 filled in the recess 19 can be reduced. The housing 10 having the protrusion can be easily formed using, for example, aluminum die casting.

[0172] A block made of, for example, aluminum may be placed in the gap between the housing 10 and the coil unit 700. This reduces the volume of the recess 19 in the housing 10. The block is thermally connected to the housing 10. This improves the heat dissipation capability of the coil device 800. The block is electrically insulated from the coil patterns on the first printed circuit board 31, the second printed circuit board 32, and the third printed circuit board 33.

[0173] The first through hole portion 31d, the second through hole portion 31e, and the fifth through hole portion 31f may be connected to each other. In other words, as shown in Fig. 13, the first printed circuit board 31 may have only one through hole. The first through hole 31i may be formed by one through hole portion. The through holes of the first core 21, the second core 22, and the fifth core 25 may pass through one through hole portion.

[0174] When the first printed circuit board 31 has only one through-hole, the through-holes of the first core 21, the second core 22, and the fifth core 25 have a greater margin of movement parallel to the third direction 103. This allows for accommodating variations in the size of the cores and facilitating positioning of the first printed circuit board 31 and each core. Furthermore, the increased margin of movement of the through-holes of the first core 21, the second core 22, and the fifth core 25 in the direction parallel to the third direction 103 makes it easier to bring each core into contact with or into close proximity with the heat dissipation portion 60, thereby improving heat dissipation capability. Note that, like the first through-hole 31i, the second through-hole 32i may be formed by a single through-hole. The third through-hole 32d, the fourth through-hole 32e, and the sixth through-hole 32f may be connected to each other.

[0175] Second Embodiment Next, the configuration of the coil device 800 of the power conversion device 900 according to the second embodiment will be described. The configuration of the coil device 800 of the power conversion device 900 according to the second embodiment is the same as the configuration of the coil device 800 of the power conversion device 900 according to the first embodiment, except for the heat dissipation section 60. Therefore, the same reference numerals are used for the same parts, and duplicated explanations will be omitted. The following description will focus on the differences from the coil device 800 according to the first embodiment.

[0176] 14 , the first heat dissipation member 61 according to the second embodiment is composed of two first members 66. In other words, the first heat dissipation member 61 is composed of two parts having the same shape. In the first heat dissipation member 61, the two first members 66 abut against each other. Similarly, the second heat dissipation member 62 is composed of two first members 66. The outer shape of the first heat dissipation member 61 according to the second embodiment may be the same as the outer shape of the first heat dissipation member 61 according to the first embodiment.

[0177] As shown in Figure 15, the shape of the first member 66 is, for example, the shape of the first heat dissipation member 61 (see Figure 6) of the power conversion device 900 according to embodiment 1, divided in half along a plane parallel to the first main surface 31a of the first printed circuit board 31.

[0178] 14 , the heat dissipation unit 60 further includes a third heat dissipation member 63 and a fourth heat dissipation member 64. The shape of the third heat dissipation member 63 is the same as the shape of the first member 66. In other words, the third heat dissipation member 63 is formed by the first member 66. The third heat dissipation member 63 is located between the first coil component 701 and the housing 10. Specifically, the third heat dissipation member 63 is disposed along the gap between the first coil component 701 and the housing 10. The third heat dissipation member 63 includes a third main portion 630, a seventeenth heat dissipation portion 631, an eighteenth heat dissipation portion 632, a nineteenth heat dissipation portion 633, and a twentieth heat dissipation portion 634.

[0179] The third main portion 630 has a flat plate shape. The third main portion 630 extends along a plane perpendicular to the first direction 101. The third main portion 630 faces the housing 10. Each of the seventeenth heat dissipation portion 631, the eighteenth heat dissipation portion 632, the nineteenth heat dissipation portion 633, and the twentieth heat dissipation portion 634 is continuous with the third main portion 630.

[0180] The first core 21 is located between the nineteenth heat dissipation portion 633 and the seventeenth heat dissipation portion 631. The second core 22 is located between the seventeenth heat dissipation portion 631 and the eighteenth heat dissipation portion 632. The fifth core 25 is located between the eighteenth heat dissipation portion 632 and the twentieth heat dissipation portion 634.

[0181] The third heat dissipation member 63 faces the third main surface 31b of the first printed circuit board 31. Specifically, each of the seventeenth heat dissipation portion 631, the eighteenth heat dissipation portion 632, the nineteenth heat dissipation portion 633, and the twentieth heat dissipation portion 634 faces the third main surface 31b.

[0182] The shape of the fourth heat dissipation member 64 is the same as the shape of the first member 66. The fourth heat dissipation member 64 is located between the third coil component 703 and the housing 10. Specifically, the fourth heat dissipation member 64 is disposed along the gap between the third coil component 703 and the housing 10. The fourth heat dissipation member 64 has a fourth main portion 640, a twenty-first heat dissipation portion 641, a twenty-second heat dissipation portion 642, a twenty-third heat dissipation portion 643, and a twenty-fourth heat dissipation portion 644.

[0183] The fourth main portion 640 has a flat plate shape. The fourth main portion 640 extends along a plane perpendicular to the first direction 101. The fourth main portion 640 faces the housing 10. Each of the twenty-first heat dissipation portion 641, the twenty-second heat dissipation portion 642, the twenty-third heat dissipation portion 643, and the twenty-fourth heat dissipation portion 644 is continuous with the fourth main portion 640.

[0184] The seventh core 27 is located between the 23rd heat dissipation portion 643 and the 21st heat dissipation portion 641. The eighth core 28 is located between the 21st heat dissipation portion 641 and the 22nd heat dissipation portion 642. The ninth core 29 is located between the 22nd heat dissipation portion 642 and the 24th heat dissipation portion 644.

[0185] The fourth heat dissipation member 64 faces the fifth main surface 33 a of the third printed circuit board 33. Specifically, each of the twenty-first heat dissipation portion 641, the twenty-second heat dissipation portion 642, the twenty-third heat dissipation portion 643, and the twenty-fourth heat dissipation portion 644 faces the fifth main surface 33 a.

[0186] According to the power conversion device 900 of the second embodiment, the heat dissipation section 60 has a third heat dissipation member 63 and a fourth heat dissipation member 64. The third heat dissipation member 63 is located between the first coil component 701 and the housing 10. This effectively improves the heat dissipation performance of the first coil component 701. The fourth heat dissipation member 64 is located between the third coil component 703 and the housing 10. This effectively improves the heat dissipation performance of the third coil component 703.

[0187] According to the power conversion device 900 of the second embodiment, the first heat dissipation member 61 and the second heat dissipation member 62 are each formed of a plurality of first members 66. The third heat dissipation member 63 and the fourth heat dissipation member 64 are each formed of the first members 66. Therefore, the same mold can be used to manufacture the first heat dissipation member 61, the second heat dissipation member 62, the third heat dissipation member 63, and the fourth heat dissipation member 64. This reduces the manufacturing cost of the coil device 800.

[0188] In the first heat dissipation member 61, heat dissipation grease such as silicone grease may be applied to the contact surface between the two first members 66. In other words, the two first members 66 are in contact with each other via the heat dissipation grease. This allows the heat dissipation grease to fill in minute irregularities on the surfaces of the first members 66. This reduces the contact thermal resistance at the contact surface between the two first members 66. As a result, the heat dissipation performance of the coil device 800 can be improved.

[0189] Instead of applying thermal grease to the contact surface between the two first members 66, a thermal dissipation sheet may be sandwiched between the two first members 66. The thermal dissipation sheet fills in minute irregularities on the surface of the first members 66. This reduces the contact thermal resistance at the contact surface between the two first members 66. As a result, the heat dissipation performance of the coil device 800 can be improved. When a thermal dissipation sheet is sandwiched between the two first members 66, the thermal dissipation sheet is sandwiched between the two first members 66 so as to crush the thermal dissipation sheet when manufacturing the coil device 800. This effectively reduces the contact thermal resistance at the contact surface between the two first members 66.

[0190] The heat dissipation portion 60 is fixed by the filler 80. Therefore, when manufacturing the coil device 800, it is not necessary to firmly fix the two first members 66 in advance in the first heat dissipation member 61. Specifically, for example, after the two first members 66 are brought into contact with each other, the two first members 66 may be fixed by attaching adhesive tape or the like to the two first members 66. This makes it possible to shorten the time required to assemble the coil device 800 compared to when the two first members 66 are firmly fixed in advance.

[0191] 16 , each of the first heat dissipation member 61 and the second heat dissipation member 62 may be made up of a plurality of second members 67. Each of the first heat dissipation member 61 and the second heat dissipation member 62 is made up of, for example, six second members 67. Each of the third heat dissipation member 63 and the fourth heat dissipation member 64 is made up of three second members 67.

[0192] 17, the second member 67 has a C-shape in plan view, which is, for example, a shape obtained by dividing the first member 66 (see FIGS. 14 and 15).

[0193] It goes without saying that the coil device 800 according to the modified example of the second embodiment can provide the same effects as the coil device 800 according to the second embodiment. Note that the configuration of the heat dissipation unit 60 according to the second embodiment is not limited to the above configuration. For example, the first heat dissipation member 61 may be configured by a plurality of parts that are L-shaped in a plan view.

[0194] Third Embodiment Next, the configuration of the coil device 800 of the power conversion device 900 according to the third embodiment will be described. The configuration of the coil device 800 of the power conversion device 900 according to the third embodiment is the same as the configuration of the coil device 800 of the power conversion device 900 according to the first embodiment, except for the heat dissipation section 60. Therefore, the same reference numerals are used for the same parts, and duplicated explanations will be omitted. The following description will focus on the differences from the coil device 800 according to the first embodiment.

[0195] 18 , the heat dissipation section 60 according to the third embodiment has a plurality of first plate members 11 and a plurality of second plate members 12. Specifically, each of the first heat dissipation member 61 and the second heat dissipation member 62 is made up of one first plate member 11 and four second plate members 12.

[0196] The first plate member 11 of the first heat dissipation member 61 is located between the first coil component 701 and the second coil component 702. Specifically, the first plate member 11 of the first heat dissipation member 61 is located between the first core 21 and the third core 23, between the second core 22 and the fourth core 24, and between the fifth core 25 and the sixth core 26.

[0197] The first plate member 11 of the first heat dissipation member 61 is disposed, for example, parallel to the first main surface 31 a of the first printed circuit board 31. Each of the multiple second plate members 12 extends along the thickness direction of the first plate member 11. In a plan view, each of the multiple second plate members 12 intersects with the first plate member 11. The thickness direction of the first plate member 11 may be the same as the first direction 101.

[0198] Each of the first core 21, the second core 22, the fifth core 25, the third core 23, the fourth core 24, and the sixth core 26 is located between two adjacent second plate members 12 of the plurality of second plate members 12 of the first heat dissipation member 61. From another perspective, one second plate member 12 of the plurality of second plate members 12 of the first heat dissipation member 61 is located between the first core 21 and the second core 22, and between the third core 23 and the fourth core 24. One second plate member 12 of the plurality of second plate members 12 of the first heat dissipation member 61 corresponds to the first heat dissipation portion 611 and the second heat dissipation portion 612 (see FIG. 6 ) of the heat dissipation unit 60 according to the first embodiment. Of the multiple second plate members 12 of the first heat dissipation member 61, one second plate member 12 is located between the second core 22 and the fifth core 25, and between the fourth core 24 and the sixth core 26. Each of the multiple second plate members 12 of the first heat dissipation member 61 faces the first main surface 31 a of the first printed circuit board 31 and the fourth main surface 32 b of the second printed circuit board 32, respectively.

[0199] The second heat dissipation member 62 has a configuration similar to that of the first heat dissipation member 61. Specifically, the first plate member 11 of the second heat dissipation member 62 is located between the second coil component 702 and the third coil component 703. Of the multiple second plate members 12 of the second heat dissipation member 62, one second plate member 12 is located between the third core 23 and the fourth core 24 and between the seventh core 27 and the eighth core 28. Similarly, of the multiple second plate members 12 of the second heat dissipation member 62, one second plate member 12 is located between the fourth core 24 and the sixth core 26 and between the eighth core 28 and the ninth core 29.

[0200] Each of the third core 23, fourth core 24, sixth core 26, seventh core 27, eighth core 28, and ninth core 29 is located between two adjacent second plate members 12 of the second heat dissipation member 62. Each of the second plate members 12 of the second heat dissipation member 62 faces the second main surface 32a of the second printed circuit board 32 and the sixth main surface 33b of the third printed circuit board 33, respectively.

[0201] 19 , slits that allow the first plate member 11 and the second plate member 12 to engage with each other are provided in at least one of the first plate member 11 and the second plate member 12. Specifically, for example, a plurality of third slits 93 are provided in the first plate member 11. For example, a fourth slit 94 is provided in the second plate member 12.

[0202] Each of the multiple third slits 93 extends in the second direction 102. Each of the multiple third slits 93 is open in the second direction 102. The multiple third slits 93 are arranged side by side in the third direction 103. The width of the third slit 93 in the third direction 103 is greater than the thickness of the second plate member 12.

[0203] The fourth slit 94 extends in the second direction 102. The fourth slit 94 is open in the direction opposite to the second direction 102. The width of the fourth slit 94 in the first direction 101 is greater than the thickness of the first plate member 11.

[0204] Each of the plurality of second plate members 12 is engaged with the first plate member 11. Specifically, a second plate member 12 is inserted into each of the plurality of third slits 93. A first plate member 11 is inserted into the fourth slit 94. The method for manufacturing the first plate member 11 and the plurality of second plate members 12 is not particularly limited, but examples thereof include press working and cutting work.

[0205] According to the power conversion device 900 of the third embodiment, the heat dissipation unit 60 includes a first plate member 11 and a second plate member 12. At least one of the first plate member 11 and the second plate member 12 has a slit that allows the first plate member 11 and the second plate member 12 to engage with each other. Therefore, by moving the first plate member 11 or the second plate member 12 within the slit, the relative position of the second plate member 12 with respect to the first plate member 11 can be adjusted. This allows the positions of the first plate member 11 and the second plate member 12 to be adjusted in accordance with core positional deviations caused by variations in core size and variations in the size of through holes provided in the printed circuit board. Therefore, interference between the core of the coil unit 700 and the heat dissipation unit 60 can be prevented.

[0206] Modification of Embodiment 3 The first plate member 11 may be inclined with respect to each of the first printed circuit board 31, the second printed circuit board 32, and the third printed circuit board 33. If the first plate member 11 is in contact with or close to the core of the coil unit 700, a cooling effect similar to that of the power conversion device 900 according to Embodiment 1 can be obtained.

[0207] The second plate member 12 may be inclined with respect to the direction perpendicular to each of the first printed circuit board 31, the second printed circuit board 32, the third printed circuit board 33, and the first plate member 11. Even in this case, a sufficient heat dissipation effect can be obtained.

[0208] In the above description, slits are provided in both the first plate member 11 and the plurality of second plate members 12, but the configuration of the heat dissipation section 60 is not limited to the above configuration. The plurality of third slits 93 may be provided in the first plate member 11, and the fourth slits 94 may not be provided in each of the plurality of second plate members 12. Conversely, the fourth slits 94 may be provided in each of the plurality of second plate members 12, and the third slits 93 may not be provided in the first plate member 11.

[0209] Fourth Embodiment Next, the configuration of the coil device 800 of the power conversion device 900 according to the fourth embodiment will be described. The configuration of the coil device 800 of the power conversion device 900 according to the fourth embodiment is the same as the configuration of the coil device 800 of the power conversion device 900 according to the first embodiment, except for the heat dissipation section 60. Therefore, the same reference numerals are used for the same parts, and duplicated explanations will be omitted. The following description will focus on the differences from the coil device 800 according to the first embodiment.

[0210] 20 , the heat dissipation section 60 according to the fourth embodiment has a first plate member 11, a fourth plate member 14, and a plurality of third plate members 13. Specifically, for example, the heat dissipation section 60 is configured by the first plate member 11, the fourth plate member 14, and four third plate members 13.

[0211] The first plate member 11 is located between the first coil component 701 and the second coil component 702. Specifically, the first plate member 11 is located between the first core 21 and the third core 23, between the second core 22 and the fourth core 24, and between the fifth core 25 and the sixth core 26. The first plate member 11 is disposed parallel to the first main surface 31 a of the first printed circuit board 31, for example.

[0212] The fourth plate member 14 is located between the second coil component 702 and the third coil component 703. Specifically, the fourth plate member 14 is located between the third core 23 and the seventh core 27, between the fourth core 24 and the eighth core 28, and between the sixth core 26 and the ninth core 29. The fourth plate member 14 is disposed, for example, parallel to the second main surface 32 a of the second printed circuit board 32.

[0213] Each of the plurality of third plate members 13 extends along the thickness direction of the first plate member 11. The thickness direction of the first plate member 11 may be the same as the first direction 101. In a plan view, each of the plurality of third plate members 13 intersects with each of the first plate member 11 and the fourth plate member 14. Each of the plurality of third plate members 13 faces a side wall surface 17 (see FIG. 2 ) of the housing 10.

[0214] Each of the first core 21, the second core 22, the fifth core 25, the third core 23, the fourth core 24, the sixth core 26, the seventh core 27, the eighth core 28, and the ninth core 29 is located between two adjacent third plate members 13 among the plurality of third plate members 13. From another perspective, among the plurality of third plate members 13, one third plate member 13 is located between the first core 21 and the second core 22, between the third core 23 and the fourth core 24, and between the seventh core 27 and the eighth core 28. Among the plurality of third plate members 13, one third plate member 13 corresponds to the first heat dissipation portion 611, the second heat dissipation portion 612, the ninth heat dissipation portion 621, and the tenth heat dissipation portion 622 (see FIG. 6 ) of the heat dissipation unit 60 according to the first embodiment. Of the multiple third plate members 13, one third plate member 13 is located between the second core 22 and the fifth core 25, between the fourth core 24 and the sixth core 26, and between the eighth core 28 and the ninth core 29.

[0215] 21 , slits that allow the first plate member 11 and the third plate member 13 to engage with each other are provided in at least one of the first plate member 11 and the third plate member 13. Specifically, for example, a plurality of third slits 93 are provided in the first plate member 11. For example, a fifth slit 95 is provided in the third plate member 13.

[0216] Each of the multiple third slits 93 extends in the second direction 102. Each of the multiple third slits 93 is open in the second direction 102. The multiple third slits 93 are arranged side by side in the third direction 103. The width of the third slit 93 in the third direction 103 is greater than the thickness of the third plate member 13.

[0217] The fifth slit 95 extends in the second direction 102. The fifth slit 95 is open in the direction opposite to the second direction 102. The width of the fifth slit 95 in the first direction 101 is greater than the thickness of the first plate member 11.

[0218] Each of the plurality of third plate members 13 is engaged with the first plate member 11. Specifically, the third plate members 13 are inserted into each of the plurality of third slits 93. The first plate members 11 are inserted into the fifth slits 95.

[0219] At least one of the fourth plate member 14 and the third plate member 13 has slits that allow the fourth plate member 14 and the third plate member 13 to engage with each other. Specifically, for example, the fourth plate member 14 has a plurality of sixth slits 96. For example, the third plate member 13 has a seventh slit 97. The sixth slits 96 correspond to the third slits 93.

[0220] The shape of the seventh slit 97 may be the same as the shape of the fifth slit 95. The seventh slit 97 is provided in the first direction 101 with respect to the fifth slit 95. The width of the seventh slit 97 in the first direction 101 is greater than the thickness of the fourth plate member 14.

[0221] Each of the plurality of third plate members 13 is engaged with the fourth plate member 14. Specifically, the third plate members 13 are inserted into each of the plurality of sixth slits 96. The fourth plate member 14 is inserted into the seventh slit 97.

[0222] A first slit 91 and a second slit 92 are formed in the third plate member 13. The first printed circuit board 31 is inserted into the first slit 91. The first slit 91 is formed in the opposite direction to the first direction 101 with respect to the fifth slit 95. The first slit 91 extends in the second direction 102. The first slit 91 is open in the opposite direction to the second direction 102. The width of the first slit 91 in the first direction 101 is greater than the thickness of the first printed circuit board 31.

[0223] The second printed circuit board 32 is inserted into the second slit 92. The second slit 92 is provided in the first direction 101 with respect to the fifth slit 95. The shape of the second slit 92 may be the same as the shape of the first slit 91.

[0224] Although not shown, an eighth slit is provided in the third plate member 13. The third printed circuit board 33 is inserted into the eighth slit. The eighth slit is provided in the first direction 101 with respect to the seventh slit 97. The shape of the eighth slit may be the same as the shape of the first slit 91.

[0225] Each of the multiple third plate members 13 is disposed so as to straddle the first printed circuit board 31, the second printed circuit board 32, and the third printed circuit board 33. From another perspective, in a plan view, each of the multiple third plate members 13 intersects with the first printed circuit board 31, the second printed circuit board 32, and the third printed circuit board 33. Each of the multiple third plate members 13 is positioned in the second direction 102 relative to each of the first printed circuit board 31, the second printed circuit board 32, and the third printed circuit board 33.

[0226] According to the power conversion device 900 of the fourth embodiment, a first slit 91 and a second slit 92 are provided in the third plate member 13. The first printed circuit board 31 is inserted into the first slit 91. The second printed circuit board 32 is inserted into the second slit 92. This makes it possible to prevent excessive change in the relative position of the third plate member 13 with respect to each of the first printed circuit board 31 and the second printed circuit board 32. This makes it possible to prevent movement of each of the first printed circuit board 31, the second printed circuit board 32, and the heat dissipation unit 60 when filling the recess 19 of the housing 10 with the filler 80 while the coil unit 700 is stored in the recess 19 during manufacture of the power conversion device 900.

[0227] Furthermore, the first coil component 701, the second coil component 702, and the heat dissipation portion 60 can be more reliably fixed together, which can suppress vibrations of the first coil component 701, the second coil component 702, and the heat dissipation portion 60. This can improve the vibration resistance of the power conversion device 900.

[0228] Fifth Embodiment Next, the configuration of a power conversion device 900 according to a fifth embodiment will be described. The power conversion device 900 according to the fifth embodiment differs from the power conversion device 900 according to the first embodiment mainly in that the coil section 700 has a switching element and a control circuit 209, but is otherwise the same as the power conversion device 900 according to the first embodiment. The following description will focus on the differences from the power conversion device 900 according to the first embodiment.

[0229] Fig. 22 shows the configuration of the power conversion device 900 shown in Fig. 1 . For ease of explanation, the filler 80 is not shown in Fig. 22 . As shown in Figs. 22 and 23 , electronic components such as switching elements are mounted on a first printed circuit board 31 according to the fifth embodiment. Specifically, for example, a primary rectifier diode 501, primary MOSFETs 502a, 502b, 502c, and 502d, secondary rectifier diodes 503a and 503b, and a connector 504a are mounted on the first printed circuit board 31. The electronic components such as the switching elements are covered with the filler 80.

[0230] The primary rectifier diode 501 corresponds to the primary rectifier circuit 201 shown in Fig. 1. The primary rectifier diode 501 has four diodes housed in one package. The four diodes constitute the primary rectifier circuit 201.

[0231] The primary MOSFETs 502a, 502b, 502c, and 502d correspond to the inverter 202 shown in FIG. 1. The primary MOSFETs 502a, 502b, 502c, and 502d form a bridge circuit. In this specification, the primary MOSFETs 502a, 502b, 502c, and 502d are also referred to as switching elements. The switching elements are electrically connected to the first coil pattern 351.

[0232] The secondary rectifier diodes 503a and 503b correspond to the secondary rectifier circuit 203 shown in Fig. 1. Each of the secondary rectifier diodes 503a and 503b has two diodes housed in one package. The four diodes included in the secondary rectifier diodes 503a and 503b constitute the secondary rectifier circuit 203.

[0233] The above electronic components are merely examples, and the packages and the number of components per package are not limited to the above configurations. For ease of explanation, other electronic components, such as the primary smoothing capacitor 207 shown in FIG. 1, are also mounted on the first printed circuit board 31, although not shown. The first printed circuit board 31 is provided with a gate drive circuit, not shown. The gate drive circuit is used to switch the primary MOSFETs 502a, 502b, 502c, and 502d.

[0234] The connector 504a is provided on the first main surface 31a and protrudes in the second direction 102 relative to the first printed circuit board 31.

[0235] A control circuit 209 (see FIG. 1) is mounted on the printed circuit board 70. The control circuit 209 outputs control signals to the switching elements to control the switching elements. The switching elements convert an input voltage and output the converted voltage. Specifically, for example, the switching elements convert a DC voltage into an AC voltage. Each of the first coil component 701, the second coil component 702, and the third coil component 703 receives the voltage output from the switching elements.

[0236] 22 , the wiring printed circuit board 70 is provided with a plurality of third connection holes 73. The connectors 504a, 504b, and 504c are inserted into the plurality of third connection holes 73. The connectors 504a, 504b, and 504c are soldered to the wiring printed circuit board 70. From another perspective, the connectors 504a, 504b, and 504c are electrically connected to the wiring printed circuit board 70 by soldering. The control circuit 209 outputs a control signal to the switching element via the connectors 504a, 504b, and 504c.

[0237] Similar to the first printed circuit board 31, electronic components such as switching elements are mounted on the second printed circuit board 32. The switching elements mounted on the second printed circuit board 32 are electrically connected to the second coil pattern 352. Similarly, electronic components such as switching elements are mounted on the third printed circuit board 33. The switching elements mounted on the third printed circuit board 33 are electrically connected to the third coil pattern 353.

[0238] According to the power conversion device 900 of the fifth embodiment, the switching elements are mounted on the first printed circuit board 31. Therefore, the electronic components such as the switching elements are covered with the filler 80. This makes it possible to suppress contamination and moisture absorption of the electronic components such as the switching elements due to the usage environment of the power conversion device 900. Therefore, it is possible to reduce the degree of contamination that needs to be considered for the electronic components such as the switching elements. This makes it possible to suppress deterioration of the insulation performance of the electronic components such as the switching elements. Therefore, it is possible to shorten the insulation distance and creepage distance that need to be considered for the electronic components such as the switching elements. As a result, it is possible to reduce the size of the power conversion device 900.

[0239] According to the power conversion device 900 of the fifth embodiment, switching elements are also mounted on each of the second printed circuit board 32 and the third printed circuit board 33. Therefore, it is possible to obtain the same effects as those achieved by mounting switching elements on the first printed circuit board 31.

[0240] According to the power conversion device 900 of the fifth embodiment, the control circuit 209 is mounted on the wiring printed circuit board 70. This allows the length of the wiring connecting the switching elements and the control circuit 209 to be shortened. This allows the power conversion device 900 to be made smaller. Furthermore, it is possible to reduce noise superimposed on the control signal output from the control circuit 209 to the switching elements. This makes it possible to suppress malfunction of the switching elements.

[0241] Although the above description has been given of a configuration in which the switching elements are MOSFETs, the switching elements are not limited to MOSFETs. The switching elements may be other types of power semiconductors, such as IGBTs (Insulated Gate Bipolar Transistors). The switching elements may be mounted on only one or two of the first printed circuit board 31, the second printed circuit board 32, and the third printed circuit board 33.

[0242] First Modification of Fifth Embodiment As shown in FIG. 24 , the wiring printed circuit board 70 may have a shielding layer 79. The shielding layer 79 faces the recess 19. The shielding layer 79 is made of metal. Specifically, the shielding layer 79 is made of copper foil. The shielding layer 79 is a solid pattern. The shielding layer 79 may occupy 80% or more of the mounting area of ​​the wiring printed circuit board 70.

[0243] The wiring printed circuit board 70 has a seventh main surface 76. The seventh main surface 76 faces the recess 19. A shielding layer 79 is provided on the seventh main surface 76, for example.

[0244] Since the wiring printed circuit board 70 has the shield layer 79, the shield layer 79 and the housing 10 form a shield that surrounds the coil section 700. This reduces electromagnetic waves that leak from the power conversion device 900. Therefore, it is possible to suppress malfunction of peripheral devices caused by noise leaking from the power conversion device 900 and induction heating caused by magnetic flux leaking from the power conversion device 900 interlinking with conductors.

[0245] Second Modification of Fifth Embodiment As shown in Fig. 25 , a power conversion device 900 may have a control printed circuit board 75. The control circuit 209 may be mounted on the control printed circuit board 75. The control printed circuit board 75 extends along a plane perpendicular to the third direction 103.

[0246] The control printed circuit board 75 is housed inside the recess 19. The control printed circuit board 75 faces the side wall surface 17 of the recess 19. A filler 80 is filled in the gaps between the control printed circuit board 75 and each of the first coil component 701, the second coil component 702, and the third coil component 703. The control printed circuit board 75 is covered with the filler 80.

[0247] The control printed circuit board 75 is located in a direction opposite to the third direction 103 relative to each of the first printed circuit board 31 , the second printed circuit board 32 , and the third printed circuit board 33 .

[0248] A connector 55a is provided on the first printed circuit board 31. The connector 55a corresponds to the first input terminal 41 and the connector 504a of the first printed circuit board 31 according to the fifth embodiment. The first printed circuit board 31 is electrically connected to the control printed circuit board 75 via the connector 55a. The first printed circuit board 31 receives an input voltage and a control signal via the connector 55a. Similarly, a connector 55b is provided on the second printed circuit board 32. A connector 55c is provided on the third printed circuit board 33.

[0249] The power conversion device 900 has an external connection connector 56 and a fourth input terminal 44. The external connection connector 56 is provided on the control printed circuit board 75. When the control circuit 209 generates a control signal, the control circuit 209 transmits and receives a signal to and from an external device (not shown) via the external connection connector 56. For example, the control circuit 209 receives a signal from the secondary voltage and current detection circuit 210 (see FIG. 1 ) via the external connection connector 56. A portion of the external connection connector 56 is exposed from the filler 80.

[0250] The fourth input terminal 44 is provided on the control printed circuit board 75. The fourth input terminal 44 corresponds to the input terminal 211 in the power conversion device 900 shown in Fig. 1. The fourth input terminal 44 is configured by a pair of terminals.

[0251] According to the power conversion device 900 of the second modification of the fifth embodiment, the control printed circuit board 75 is housed inside the recess 19. Therefore, the control printed circuit board 75 is shielded by the housing 10. This reduces noise received by the control circuit 209. This makes it possible to suppress malfunction of the switching elements.

[0252] According to the power conversion device 900 according to the second modification of the fifth embodiment, the control printed circuit board 75 is covered with the filler 80. Therefore, it is possible to suppress vibration of the control printed circuit board 75.

[0253] Covering the control printed circuit board 75 with the filler 80 can suppress contamination and moisture absorption of the control printed circuit board 75 due to the usage environment of the power conversion device 900. This can prevent deterioration of the insulation performance of the control printed circuit board 75.

[0254] By suppressing contamination and moisture absorption of the control printed circuit board 75 due to the environment in which the power conversion device 900 is used, it is possible to shorten the insulation distance and creepage distance that must be considered. This allows the control printed circuit board 75 to be made smaller. As a result, the power conversion device 900 can be made smaller.

[0255] The configurations shown in the above embodiments are examples of the contents of the present disclosure, and may be combined with other known technologies, or parts of the configurations may be omitted or modified within the scope of the gist of the present disclosure.

[0256] The power conversion device according to the present disclosure is not limited to the above-described embodiment, and may be applied to forms other than those exemplified in the above-described embodiment. In addition, the materials, shapes, dimensions, and quantities of the housing, core, printed circuit board, filler, etc. are not limited to those exemplified in the above-described embodiment.

[0257] The embodiments disclosed herein are to be considered as illustrative in all respects and not restrictive. The scope of the present disclosure is defined by the claims, not by the above description, and is intended to include meanings equivalent to the claims and all modifications within the scope thereof.

[0258] 1c First through-hole, 2c Second through-hole, 3c Third through-hole, 4c Fourth through-hole, 10 Housing, 19 Recess, 21 First core, 22 Second core, 23 Third core, 24 Fourth core, 31 First printed circuit board, 31a First main surface, 31d First through-hole, 31e Second through-hole, 31i First through-hole, 32 Second printed circuit board, 32a Second main surface, 32d Third through-hole, 32e Fourth through-hole, 32i Second through-hole, 41 First input terminal, 42 Second input terminal, 51 First output terminal, 52 Second output terminal, 60 Heat dissipation portion, 70 Wiring printed circuit board, 75 Control printed circuit board, 80 Filler, 91 First slit, 92 Second slit, 93 Third slit, 94 Fourth slit, 95 Fifth slit, 96 Sixth slit, 97 Seventh slit, 209 control circuit, 351 first coil pattern, 352 second coil pattern, 611 first heat dissipation portion, 612 second heat dissipation portion, 701 first coil component, 702 second coil component, 900 power conversion device.

Claims

1. A device comprising: a first coil component; a second coil component arranged alongside the first coil component; a heat dissipation section located between the first coil component and the second coil component; and a housing having a recess for accommodating the first coil component, the second coil component, and the heat dissipation section, and being thermally connected to the heat dissipation section, wherein the first coil component comprises: a first printed circuit board having a first coil pattern and having a first through hole; a first core having a first through portion that passes through the first through hole; and a second core having a second through portion that passes through the first through hole, the first through hole being adjacent to the first coil pattern; the second coil component comprises: a second printed circuit board having a second coil pattern and having a second through hole; a third core having a third through portion that passes through the second through hole; and a fourth core having a fourth through portion that passes through the second through hole, the second through hole being adjacent to the second coil pattern; a first heat dissipation portion located between the first core and the second core and facing the first printed circuit board; and a second heat dissipation portion located between the third core and the fourth core and facing the second printed circuit board.

2. The power conversion device according to claim 1, wherein the heat dissipation section is located between the first core and the third core, and between the second core and the fourth core.

3. A power conversion device as described in claim 1 or claim 2, wherein the first printed circuit board has a first main surface in which the first through hole is provided, the second printed circuit board has a second main surface in which the second through hole is provided, and each of the first printed circuit board and the second printed circuit board is arranged so that the second main surface is along a plane parallel to the first main surface.

4. A power conversion device according to any one of claims 1 to 3, wherein the heat dissipation section is composed of a plurality of components of the same shape.

5. A power conversion device as described in any one of claims 1 to 3, wherein the heat dissipation section has a first plate member and a second plate member, the first plate member being located between the first core and the third core and between the second core and the fourth core, the second plate member extending along the thickness direction of the first plate member, and at least one of the first plate member and the second plate member having a slit for engaging the first plate member with the second plate member.

6. A power conversion device as claimed in any one of claims 1 to 3, wherein the heat dissipation section has a first plate member and a third plate member, the first plate member being located between the first core and the third core and between the second core and the fourth core, the third plate member extending in the thickness direction of the first plate member, at least one of the first plate member and the third plate member being provided with a slit for engaging the first plate member with the third plate member, and the third plate member being provided with a first slit for inserting the first printed circuit board and a second slit for inserting the second printed circuit board.

7. A power conversion device according to any one of claims 1 to 6, further comprising a filler made of an insulating material and positioned within the recess, the filler filling gaps among the housing, the first coil component, the second coil component, and the heat dissipation component.

8. A power conversion device as described in claim 7, further comprising: a switching element electrically connected to each of the first coil pattern and the second coil pattern; and a control circuit that outputs a control signal to the switching element to control the switching element, wherein the switching element is mounted on at least one of the first printed circuit board or the second printed circuit board.

9. The power conversion device according to claim 8, further comprising a wiring printed circuit board covering at least a portion of the opening of the recess, wherein the first coil component has a first input terminal and a first output terminal, the second coil component has a second input terminal and a second output terminal, the wiring printed circuit board electrically connecting the first input terminal and the second input terminal and electrically connecting the first output terminal and the second output terminal, and the control circuit is mounted on the wiring printed circuit board.

10. The power conversion device according to claim 9, wherein the wiring printed circuit board has a shielding layer made of metal, the shielding layer facing the recess.

11. The power conversion device according to claim 8, further comprising a control printed circuit board on which the control circuit is mounted, the control printed circuit board being housed inside the recess, and the filler being filled in gaps between the control printed circuit board and each of the first coil component and the second coil component.

12. A power conversion device as described in any one of claims 1 to 11, wherein the first through hole has a first through hole portion through which the first through hole portion passes, and a second through hole portion through which the second through hole portion passes and which is separated from the first through hole portion, and the second through hole has a third through hole portion through which the third through hole portion passes, and a fourth through hole portion through which the fourth through hole portion passes and which is separated from the third through hole portion.

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