Power conversion device

Abstract

To provide a power conversion device that enables high-density mounting of a substrate while ensuring heat dissipation performance.SOLUTION: A power conversion device 1 includes: a plurality of substrates 111a to 113b; and a cylindrical heat sink 12. The heat sink 12 includes: a first main surface 121 and a second main surface 122 facing each other along a predetermined direction and each having an opening; and a side surface 123 sandwiched between the first main surface 121 and the second main surface 122. A circuit for power conversion is mounted on each of the plurality of substrates 111a to 113b. The plurality of substrates 111a to 113b are disposed so as to surround the side surface 123 when viewed from the predetermined direction. The heat sink 12 dissipates heat generated by each circuit of the plurality of substrates 111a to 113b to an internal space SP1 which is a space surrounded by the side surface 123.SELECTED DRAWING: Figure 6

Description

[Technical Field]

[0001] The present disclosure relates to a power conversion device, and more particularly to a power conversion device having a heat dissipation function. [Background technology]

[0002] Patent document 1 describes an installed power conversion device that includes a housing, a partition wall that separates the space within the housing into a circuit component accommodating space and a duct space extending in the vertical direction, a waterproof box that is positioned below the circuit component accommodating space and that accommodates some of the electrical circuit components, a board that has a component mounting surface and a heat dissipation surface, and a heat sink that protrudes from the heat dissipation surface of the board. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] Japanese Patent Publication No. 2020-36456 Summary of the Invention [Problem to be solved by the invention]

[0004] In the installed power conversion device of Patent Document 1, the electrical circuit components are simply arranged vertically within the housing, making it difficult to achieve high-density mounting of the boards while ensuring heat dissipation performance.

[0005] An object of the present disclosure is to provide a power conversion device that enables high-density mounting on a board while ensuring heat dissipation performance. [Means for solving the problem]

[0006] A power conversion device according to one aspect of the present disclosure includes a plurality of substrates and a cylindrical heat sink. The heat sink faces each other along a predetermined direction and includes first and second main surfaces, each having an opening, and side surfaces sandwiched between the first and second main surfaces. Each of the plurality of substrates is mounted with a circuit for power conversion. The plurality of substrates are arranged to surround the side surfaces when viewed from the predetermined direction. The heat sink dissipates heat generated by the circuit on each of the plurality of substrates into an internal space surrounded by the side surfaces. [Effects of the Invention]

[0007] The power conversion device of the present disclosure has the advantage of being able to ensure heat dissipation performance while enabling high-density mounting on a board. [Brief explanation of the drawings]

[0008] [Figure 1] FIG. 1 is a perspective view of the front surface of a power conversion device according to an embodiment of the present disclosure. [Figure 2] FIG. 2 is a perspective view of the rear side of the power converter. [Figure 3] FIG. 3 is an exploded perspective view showing the assembly structure of an outer panel of the power converter. [Figure 4] FIG. 4 is an exploded perspective view further illustrating the assembly structure of the inner panel of the power converter. [Figure 5] FIG. 5 is an exploded perspective view of the rear side of the device body of the power converter. [Figure 6] FIG. 6 is a cross-sectional view schematically showing a cross section of a main part of the device main body in the front-rear direction. [Figure 7] 7A and 7B are perspective views of the right and left front sides of the device main body, respectively. [Figure 8] FIG. 8 is an exploded perspective view of a heat dissipation structure in the device body, which is made up of a heat sink and a plurality of substrates. [Figure 9]Fig. 9A is a top view of the heat dissipation structure of the same. Fig. 9B is a top view showing a first modified example of the heat dissipation structure of the same. Fig. 9C is a top view showing a second modified example of the heat dissipation structure of the same. Fig. 9D is a top view showing a third modified example of the heat dissipation structure of the same. Fig. 9E is a top view showing a fourth modified example of the heat dissipation structure of the same. Fig. 9F is a top view showing a fifth modified example of the heat dissipation structure of the same. [Figure 10] Fig. 10A is a top view showing the arrangement of multiple heat generating elements in the heat dissipation structure of the same, Fig. 10B is a top view showing a first modified example of the arrangement of the multiple heat generating elements of the same, and Fig. 10C is a top view showing the arrangement of the multiple heat generating elements of the same and the relationship between the inner panel and the outer panel. [Figure 11] Fig. 11A is a cross-sectional view showing an intake / exhaust mechanism in the device body, which is made up of an exhaust port, an intake port, and a pair of fans and cooperates with the heat dissipation mechanism. Fig. 11B is a cross-sectional view showing a first modified example of the relationship between the heat sink and the inner panel. Fig. 11C is a cross-sectional view showing a second modified example of the relationship between the heat sink and the inner panel. [Figure 12] Fig. 12A is a cross-sectional view schematically showing a first modified example of the intake and exhaust mechanism of the same, Fig. 12B is a cross-sectional view schematically showing a second modified example of the intake and exhaust mechanism of the same, Fig. 12C is a cross-sectional view schematically showing a third modified example of the same, and Fig. 12D is a cross-sectional view schematically showing a modified example of the outer panel of the same. [Figure 13] 13A, 13B, and 13C are top views showing a first, a second, and a third modified example of the inner panel, respectively, of the same inner panel. [Figure 14] 14A, 14B, and 14C are top views schematically showing a first, a second, and a third modified example of the outer panel of the same. DETAILED DESCRIPTION OF THE INVENTION

[0009] (1) Overview: Heat dissipation structure and dual housing structure The power conversion device 1 according to the embodiment of the present disclosure is a stationary type and is placed vertically as shown in FIG.

[0010] As shown in Figures 3 to 8 and 11A, the power conversion device 1 includes multiple substrates (upper first substrate 111a to lower third substrate 113b: hereinafter referred to as "multiple substrates 111a to 113b"), a heat sink 12, and a housing 13.

[0011] (1-1) Heat dissipation structure The heat dissipation structure in this embodiment is realized by a plurality of substrates 111a to 113b and a heat sink 12 as shown in FIGS.

[0012] (1-1-1) Multiple substrates and heat generating circuits Each of the plurality of boards 111a to 113b has a circuit mounted thereon for power conversion, which in this embodiment is a heat generating circuit 11B (see FIG. 10A) that generates heat.

[0013] (1-1-2) Heat sink: cylindrical shape 6 and 8, the heat sink 12 has a cylindrical shape with an open upper surface 121 and a lower surface 122. Such a cylindrical shape may also be called a "chimney type."

[0014] Furthermore, such a heat sink 12 may be referred to as a "cylindrical heat sink 12 having openings on both bottom surfaces." The two bottom surfaces are a first main surface and a second main surface that face each other along a predetermined direction. In this embodiment, the predetermined direction is a vertical direction (vertically upward or vertically downward), but it may also be a diagonal direction (diagonally upward or diagonally downward) or a horizontal direction. Here, one of the two bottom surfaces (the first main surface) is the upper surface 121, and the other (the second front surface) is the lower surface 122. In the examples of FIGS. 6 and 8, most of the bottom surface is open, but the opening may be of a certain size or larger relative to the bottom surface (for example, an area ratio of 80% or more, 60% or more, etc.).

[0015] In the heat sink 12 of this embodiment, both bottom surfaces are congruent with each other, and either of the bottom surfaces may be the upper surface 121. However, the heat sink 12 may be distinguished as to which of the bottom surfaces is the upper surface 121 and which is the lower surface 122, for example, based on at least one of the size and shape, or functionally.

[0016] The cylindrical shape in this embodiment is a quadrangular prism cylindrical shape as shown in Fig. 8. The quadrangular prism cylindrical shape is a cylindrical shape in which the open upper surface 121 and lower surface 122 are each quadrilateral (rectangular in the example of Fig. 8).

[0017] (1-1-2a) Side of the heat sink The side surface 123 of the heat sink 12 is the surface sandwiched between both bottom surfaces, i.e., the top surface 121 and the bottom surface 122. The side surface 123 of the heat sink 12 is composed of three or more flat surfaces or a single curved surface. In the case of the heat sink 12 having a rectangular prism-like cylindrical shape in this embodiment, the side surface 123 is composed of four flat surfaces, i.e., a first side surface 123a to a fourth side surface 123d, as shown in FIGS. 8 and 9A.

[0018] In the case of heat sink 12 having a cylindrical cylindrical shape (see "Fifth Modified Example of Heat Dissipation Structure"), side surface 123 is a single curved surface as shown in FIG. 9F.

[0019] (1-1-3) Arrangement of multiple boards on a heat sink As shown in FIGS. 9A to 9F, the plurality of substrates 111a to 113b are arranged so as to surround the side surface 123 of the heat sink 12 in top view.

[0020] Surrounding the side surface 123 of the heat sink 12 in top view means that, for example, as shown in FIG. 9A, a plurality of substrates 111a to 113a are arranged around the side surface 123 of the heat sink 12.

[0021] However, surrounding the side surface 123 of the heat sink 12 in a top view may mean arranging the plurality of substrates 111a to 113b around a surface obtained by expanding the side surface 123 of the heat sink 12 in the vertical direction. In other words, as long as the plurality of substrates 111a to 113b surround the side surface 123 of the heat sink 12 in a top view, they may be located below the open lower surface 122 of the heat sink 12 or above the open upper surface 121 of the heat sink 12 in a side view. Furthermore, one substrate may extend above or below the side surface 123 of the heat sink 12 in a side view.

[0022] 7A, 7B, and 8, in this embodiment, the upper first substrate 111a to the upper third substrate 113a are arranged around the side surface 123 of the heat sink 12, and in addition, the lower first substrate 111b to the lower third substrate 113b are further arranged below the side surface 123. However, in the example of FIG. 8, the upper first substrate 111a to the upper third substrate 113a may not be arranged around the side surface 123, and only the lower first substrate 111b to the lower third substrate 113b may be arranged below the side surface 123.

[0023] 10A, the upper first substrate 111a includes a base 11A on which a heat generating circuit 11B is mounted, and a pair of support members 11C that support the base 11A with the heat generating circuit 11B in contact with the first side surface 123a of the heat sink 12. The upper second substrate 112a and the upper third substrate 113a are each configured similarly to the upper first substrate 111a.

[0024] (1-1-4) Heat dissipation to the internal space The heat sink 12 dissipates heat generated by each circuit (heat-generating circuit 11B) of the plurality of substrates 111a to 113b into an internal space SP1. The internal space SP1 is a space surrounded by side surfaces 123 of the heat sink 12. In this embodiment, the internal space SP1 is a space for cooling the plurality of substrates 111a to 113b that have become hot due to the heat from the heat-generating circuits 11B.

[0025] The heat released into the internal space SP1 is discharged to the outside of the internal space SP1 and eventually the housing 13 (the inner panel 131 and the outer panel 132) via an air current flowing vertically (usually from bottom to top) through the internal space SP1.

[0026] (1-1-5) Advantages of heat dissipation structure According to the heat dissipation structure of this embodiment, multiple substrates 111a to 113b are arranged to surround the side surface 123 of a cylindrical heat sink 12 having an open upper surface 121 and lower surface 122, so that the heat generated by each heat generating circuit 11B of the multiple substrates 111a to 113b is efficiently dissipated in different directions from multiple parts of the side surface 123 toward the internal space SP1 surrounded by the side surface 123 (i.e., while avoiding interference of heat transfer routes between the multiple substrates 111a to 113b).

[0027] This heats the air in the internal space SP1, and generates an air current that flows from bottom to top through the internal space SP1, causing the heat in the internal space SP1 to be released to the outside of the internal space SP1.

[0028] Even if the amount of heat dissipated into the internal space SP1 increases due to high-density mounting, the heat within the internal space SP1 is discharged to the outside of the internal space SP1 due to an increase in the airflow flowing from bottom to top through the internal space SP1, making it possible to achieve high-density mounting of substrates (upper first substrate 111a to lower third substrate 113b, etc.: hereinafter referred to as "substrates 111a to 113c") while maintaining heat dissipation performance.

[0029] (1-2) Housing: Double structure The housing 13 has a double structure consisting of an inner panel 131 and an outer panel 132 .

[0030] (1-2-1) Inner panel and circuit space The inner panel 131 forms a circuit space SP2 between itself and the heat sink 12. The circuit space SP2 is a space in which the plurality of boards 111a to 113b are arranged. In this embodiment, the circuit space SP2 is a space that is surrounded by the inner panel 131 around the cylindrical heat sink 12. By arranging the plurality of boards 111a to 113b in the circuit space SP2, waterproof and dustproof performance is ensured for the plurality of boards 111a to 113b in the circuit space SP2.

[0031] Furthermore, since the inner panel 131 is made of sheet metal, EMC (Electromagnetic Compatibility) can be further ensured.

[0032] (1-2-2) Outer panel 6 and 11A, outer panel 132 covers inner panel 131. Outer panel 132 is a panel that covers the outside of inner panel 131 to improve design, and does not necessarily contribute to ensuring waterproof and dustproof performance.

[0033] (1-2-3) Advantages of double structure In the power converter 1 of this embodiment, by employing a double-structured housing 13, the inner panel 131 ensures waterproof and dustproof performance, while the outer panel 132 can improve the design.

[0034] Specifically, the inner panel 131 provides a circuit space SP2 between the heat sink 12 (for example, around the heat sink 12), and thus waterproof and dustproof performance is ensured by arranging the plurality of boards 111a to 113b in the circuit space SP2. Furthermore, since the waterproof and dustproof performance is ensured by the inner panel 131, there is less need for the outer panel 132 to have waterproof and dustproof performance, and the degree of freedom in designing the outer panel 132 increases, and therefore the outer panel 132 can be used to improve design.

[0035] It should be noted that even the outer panel 132 that emphasizes design can contribute to further improvement of waterproof and dustproof performance.

[0036] (2) Details (2-1) Heat sinks distributed to three sides In this embodiment, the multiple substrates 111a to 113b are distributed and arranged on three of the four side surfaces (first side surface 123a to fourth side surface 123d: hereinafter referred to as "four side surfaces 123a to 123d") of a heat sink 12 having a rectangular cylindrical shape as shown in Figures 8 and 9A, specifically, on the first side surface 123a to the third side surface 123c.

[0037] In this configuration, heat generated by each of the plurality of substrates 111a to 113b distributed on the first to third side surfaces 123a to 123c is dissipated in different directions from the first to third side surfaces 123a to 123c toward the internal space SP1. This ensures heat dissipation performance while enabling even higher density mounting of the substrates 111a to 113b.

[0038] (2-2) Details of multiple boards As shown in Fig. 8, the multiple boards 111a to 113b in this embodiment include a first board group 111, a second board group 112, and a third board group 113. The first board group 111 is a group of boards arranged on the first side surface 123a of the four side surfaces 123a to 123d. The first side surface 123a is the side surface located on the front side (i.e., the front) when viewed from the user. The first board group 111 includes an upper first board 111a and a lower first board 111b. For example, the upper first board 111a is a control board, and the lower first board 111b is a power supply board.

[0039] Second substrate group 112 is a group of substrates arranged on second side surface 123b of four side surfaces 123a to 123d. Second side surface 123b is a side surface perpendicular to first side surface 123a, and in this embodiment, is the side surface located on the right side as seen from the user. Second substrate group 112 includes upper second substrate 112a and lower second substrate 112b. For example, upper second substrate 112a is a bus-side main substrate, and lower second substrate 112b is a bus-side filter substrate.

[0040] The third board group 113 is a group of boards arranged on the third side face 123c of the four side faces 123a to 123d. The third side face 123c is a side face perpendicular to the first side face 123a and parallel to the second side face 123b, and in this embodiment, is the side face located on the left side as seen from the user. The third board group 113 includes an upper third board 113a and a lower third board 113b. For example, the upper third board 113a is an EV-side main board, and the lower third board 113b is an EV-side filter board.

[0041] In this embodiment, "parallel" does not necessarily mean that two surfaces are completely parallel, but also includes a case where the angle between the two surfaces (specifically, the angle between two normal lines corresponding to the two surfaces) is equal to or smaller than a threshold value. The threshold value is, for example, 5 degrees or 10 degrees, but is not limited to this. Similarly, "perpendicular" in this embodiment does not necessarily mean that two surfaces are completely perpendicular, but also includes a case where the difference between the angle between the two surfaces and 90 degrees is equal to or smaller than a threshold value. The threshold value is, for example, 5 degrees or 10 degrees, but is not limited to this.

[0042] Furthermore, the various types of substrates listed above are merely examples and may be changed as appropriate. Furthermore, the number of substrates constituting one substrate group is not limited to two. In other words, each of first substrate group 111 to third substrate group 113 only needs to include one or more substrates, and the type of one or more substrates does not matter.

[0043] According to this configuration, the heat generated by the first substrate group 111 is dissipated from the first side surface 123a of the heat sink 12, the heat generated by the second substrate group 112 is dissipated from the second side surface 123b of the heat sink 12, and the heat generated by the third substrate group 113 is dissipated from the third side surface 123c of the heat sink 12 in directions that face or intersect with each other toward the internal space SP1, thereby avoiding interference between the heat transfer paths from the multiple substrate groups (first substrate group 111 to third substrate group 113) to the internal space SP1 and thereby improving heat dissipation performance.

[0044] (2-3) Relationship between the heat sink and the inner panel 6, the inner panel 131 in this embodiment extends downward below the open lower surface 122 of the heat sink 12. In other words, the length of the heat sink 12 in the vertical direction is shorter than the length of the inner panel 131 in the vertical direction.

[0045] 6 and 11A, the circuit space SP2 includes a first circuit space SP21 and a second circuit space SP22. The first circuit space SP21 is the space in the circuit space SP2 that is located around the side surface 123 of the heat sink 12 in a side view. The second circuit space SP22 is the space in the circuit space SP2 that is located below the open lower surface 122 of the heat sink 12 in a side view.

[0046] Some of the multiple substrates 111a to 113b (upper first substrate 111a to upper third substrate 113a) are arranged in a first circuit space SP21 of the circuit space SP2. The remaining some of the multiple substrates 111a to 113b (lower first substrate 111b to lower third substrate 113b) are arranged in a second circuit space SP22 of the circuit space SP2.

[0047] In this configuration, by using a heat sink 12 whose vertical length is shorter than that of the inner panel 131, a circuit space SP2 is secured not only around but also below the heat sink 12. By arranging some of the multiple boards 111a to 113b in a first circuit space SP21 between the side surface 123 of the heat sink 12 and the inner panel 131, and some of the remaining boards in a second circuit space SP22 below the heat sink 12, even higher density mounting can be achieved.

[0048] Furthermore, by including a first circuit space SP21 around the heat sink 12 and a second circuit space SP22 below the heat sink 12, it is possible to achieve further density while avoiding mutual interference of heat transferred from the multiple substrates 111a to 113b to the heat sink 12.

[0049] (2-4) Exhaust and intake ports 6 and 11A, the power conversion device 1 further includes an exhaust port 14 and an intake port 15. The exhaust port 14 is provided above the open upper surface 121 of the heat sink 12. The intake port 15 is provided below the open lower surface 122 of the heat sink 12.

[0050] The exhaust port 14 exhausts the air in the internal space SP1 to the outside of the housing 13 having the inner panel 131 and the outer panel 132. The intake port 15 draws the air outside the housing 13 into the internal space SP1.

[0051] According to this configuration, air in the internal space SP1 is discharged to the outside of the housing 13 through the exhaust port 14, while air from outside the housing 13 is taken into the internal space SP1 through the intake port 15, thereby enabling ventilation by utilizing the rising air (updraft) in the internal space SP1 that has been heated by heat dissipation, and ultimately heat dissipation to the outside.

[0052] Furthermore, by arranging the exhaust port 14 and the intake port 15 at positions sandwiching the heat sink 12 from above and below, ventilation can be performed efficiently regardless of the relative length of the heat sink 12 with respect to the housing 13.

[0053] (2-5) Fans As shown in Fig. 5 and Fig. 11A, the power conversion device 1 further includes a plurality of fans 16. In the example of Fig. 5, two fans 16 are provided for each of the exhaust port 14 and the intake port 15. However, it is sufficient that at least one fan 16 is provided for each of the exhaust port 14 and the intake port 15. This can improve ventilation efficiency and, in turn, heat dissipation performance.

[0054] (2-6) Details of a heat sink suitable for side placement 1: Heat dissipation fins in the internal space 8, 9A, 10A, and 11A, the heat sink 12 has one or more heat dissipation fins 124. The one or more heat dissipation fins 124 are arranged in the internal space SP1 parallel to the first side surface 123a. As a result, the one or more heat dissipation fins 124 are perpendicular to each of the second side surface 123b and the third side surface 123c, and each of the one or more heat dissipation fins 124 has a pair of ends thermally coupled to the second side surface 123b and the third side surface 123c, respectively.

[0055] In this embodiment, the side surface 123 of the heat sink 12 and each of the plurality of heat dissipation fins 124 are made of aluminum, but they may be made of a material other than aluminum that has high thermal conductivity. For example, copper, which is easy to process, is suitable as a material other than aluminum that has high thermal conductivity.

[0056] According to this configuration, one or more heat dissipation fins 124 arranged in the internal space SP1 parallel to the first side surface 123a promote heat dissipation without impeding the airflow from bottom to top, thereby improving heat dissipation performance.

[0057] Furthermore, by thermally coupling one or more heat dissipation fins 124 to the second side surface 123b and the third side surface 123c, it is possible to improve the heat dissipation capacity compared to, for example, a case where one or more heat dissipation fins 124 are arranged parallel to each of the second side surface 123b and the third side surface 123c and are thermally coupled to the first side surface 123a and the fourth side surface 123d on which no substrate is arranged.

[0058] (2-7) Details of heat sink suitable for 3-side layout 2: Width of each side In the heat sink 12 of this embodiment, as shown in FIGS. 8, 9A, and 10A, the width of each of the second side surface 123b and the third side surface 123c is greater than the width of the first side surface 123a.

[0059] Since the width of each of the second side surface 123b and the third side surface 123c is larger than the width of the first side surface 123a, high-density mounting can be easily achieved compared to, for example, a case where the width of the second side surface 123b and the third side surface 123c is smaller than the width of the first side surface 123a.

[0060] (2-8) Assembly structure of inner panel 3 and 4, the inner panel 131 has an assembled structure in which a plurality of inner panel components 1311 are assembled. In this embodiment, the plurality of inner panel components 1311 are three inner panel components 1311 shown in FIG. 4, namely, a first inner panel component 1311a to a third inner panel component 1311c, and may be hereinafter referred to as "the plurality of inner panel components 1311a to 1311c." Each of the plurality of inner panel components 1311a to 1311c is a component of the inner panel 131.

[0061] The inner panel 131 may be configured with four inner panel components 1311a to 1311d, including three inner panel components 1311a to 1311c shown in Fig. 4 and a fourth inner panel component 1311d, which is another inner panel component 1311, shown in Fig. 5. However, while the first inner panel component 1311a to the third inner panel component 1311c are easily attached to and detached from the main body of the power conversion device 1 (hereinafter referred to as "device main body 1A"), the fourth inner panel component 1311d is attached to the device main body 1A in advance and is not easily attached to and detached from the device main body 1A, and is therefore excluded from the components of the inner panel 131.

[0062] Because the inner panel 131 has an assembly structure, the inner panel 131 can be disassembled into multiple inner panel components 1311a to 1311c, and by using the multiple inner panel components 1311a to 1311c, it is possible to improve accessibility to each of the multiple boards 111a to 113b (facilitating inspection and repair).

[0063] (2-9) Outer panel assembly structure 1 to 3, the outer panel 132 has an assembled structure in which a plurality of outer panel components 132 are assembled. In this embodiment, the plurality of outer panel components 132 are a first outer panel component 1321a to a fourth outer panel component 1321d, and may hereinafter be referred to as "a plurality of outer panel components 1321a to 1321d." Each of the plurality of outer panel components 1321a to 1321d is a component of the outer panel 132.

[0064] Because the outer panel 132 has an assembly structure, the outer panel 132 can be disassembled into multiple outer panel components 1321a to 1321d, and by using the multiple outer panel components 1321a to 1321d, it is possible to improve accessibility to each of the multiple boards 111a to 113b (facilitating inspection and repair).

[0065] (2-10) Construction space As shown in Fig. 6 and Fig. 11A, the outer panel 132 extends downward beyond the lower end of the inner panel 131. The outer panel 132 provides an installation space SP3 below the circuit space SP2. The installation space SP3 is a space for accommodating installation parts used during installation. The installation parts include, for example, the charging cable 18 and various connection terminals.

[0066] According to this configuration, by utilizing the construction space SP3 during construction, construction efficiency can be improved.

[0067] (2-11) Insulation sheet 4 and 5, the power converter 1 further includes an insulating sheet 17. The insulating sheet 17 is provided between the inner panel 131 and the plurality of substrates 111a to 113b.

[0068] According to this configuration, by providing an insulating sheet 17 between the multiple substrates 111a to 113b and the inner panel 131, it is possible to improve the insulation of each of the multiple substrates 111a to 113b, and also the wiring connecting the multiple substrates 111a to 113b, from the inner panel 131.

[0069] If the insulation distance between the plurality of substrates 111a to 113b and the inner panel 131 is equal to or greater than a threshold value, the insulating sheet 17 may be omitted.

[0070] (3) Specific examples Next, a description will be given of a specific example of the power conversion device 1. Note that in the following, the description of the previously mentioned items will be omitted or simplified.

[0071] The power conversion device 1 in this specific example is a stationary power conversion device for using at home electric power stored in a battery mounted on an electric vehicle. As shown in FIGS. 1 to 4, the power conversion device 1 includes a device main body 1A, an inner panel 131, an outer panel 132, and a top panel 133. The inner panel 131 and the outer panel 132 form a double-structured housing 13 (see FIG. 11A) that houses the device main body 1A. A certain gap is maintained between the inner panel 131 and the outer panel 132 by interposing a plurality of spacers 134 (see FIG. 3).

[0072] 3, the top panel 133 is attached to the open upper surface of the outer panel 132. However, the top panel 133 may be included as a component of the outer panel 132.

[0073] During normal use of the power conversion device 1, the device main body 1A is partially covered by an inner panel 131 and entirely covered by an outer panel 132 and a top panel 133, as shown in Figures 1, 2, and 6. For the purpose of inspecting or repairing the power conversion device 1, the outer panel 132 is disassembled into four outer panel components 1321a to 1321d, and when the four outer panel components 1321a to 1321d are removed from the device main body 1A together with the top panel 133, the inner panel 131 appears as shown in Figure 3.

[0074] (3-1) Outer panel assembly structure 1 to 3, the outer panel 132 in this example is formed by assembling a first outer panel component 1321a, a second outer panel component 1321b, a third outer panel component 1321c, and a fourth outer panel component 1321d. Each of the first outer panel component 1321a to the fourth outer panel component 1321d is made of painted sheet metal.

[0075] The first outer panel component 1321a is disposed on the front side of the device body 1A, the second outer panel component 1321b is disposed on the right side of the device body 1A, the third outer panel component 1321c is disposed on the left side of the device body 1A, and the fourth outer panel component 1321d is disposed on the rear side of the device body 1A.

[0076] The fourth outer panel component 1321d is composed of an upper panel 132A corresponding to the circuit space SP2 and a lower panel 132B corresponding to the installation space SP3. The upper panel 132A and the lower panel 132B can be attached and detached individually to the device main body 1A. In this specific example, none of the first outer panel component 1321a to the third outer panel component 1321c are divided into an upper panel 132A and a lower panel 132B. For example, when installing the power conversion device 1, removing the lower panel 132B of the fourth outer panel component 1321d as needed facilitates access to installation components such as the charging cable 18 housed in the installation space SP3, thereby improving installation efficiency.

[0077] Specifically, when installing a PF (Plastic Flexible Conduit) pipe, it is generally necessary to remove the first outer panel component 1321a on the front side and the fourth outer panel component 1321d on the back side among the first to fourth outer panel components 1321a to 1321d, but in this example, installation of the PF pipe is possible by removing the first outer panel component 1321a and the lower panel 132B of the fourth outer panel component 1321d. Therefore, the fourth outer panel component 1321d is not divided, and installation is easier than when the entire fourth outer panel component 1321d is removed together with the first outer panel component 1321a.

[0078] In addition, when installing underground wiring, by removing the first outer panel component 1321a on the front side of the first outer panel component 1321a to the fourth outer panel component 1321d, it is possible to install underground wiring using the installation space SP3, so there is no need to remove either the upper panel 132A or the lower panel 132B of the fourth outer panel component 1321d on the back side.

[0079] 1, a gun holder 19a and a cable hook 19b are attached to second outer panel component 1321b. Charging cable 18 is hung on cable hook 19b, and the tip of charging cable 18 is housed in gun holder 19a.

[0080] (3-2) Intake and exhaust mechanism for outer panel An intake slit SL2 is formed in the center of the upper panel 132A constituting the fourth outer panel component 1321d. The intake slit SL2 is a slit that allows air outside the outer panel 132 (hereinafter sometimes referred to as "outside air") to be taken in (i.e., intake air) through the intake port 15 into the internal space SP1.

[0081] An exhaust member SL3 is attached to the top of the upper panel 132A. The exhaust member SL3 is a member for changing the direction of air discharged from the exhaust port 14 (hereinafter, sometimes referred to as the "exhaust direction") from sideways to downwards.

[0082] Outside air passes through the intake slit SL2 of the fourth outer panel component 1321d and further through the intake slit SL1 (described later) of the fourth inner panel component 1311d, and is taken in through the intake port 15. The taken-in outside air enters the internal space SP1 from the open lower surface 122 of the heat sink 12, and is heated by heat radiation from the heat sink 12. The air in the internal space SP1 thus heated enters the exhaust port 14 from the open upper surface 121 of the heat sink 12, and is discharged downward through the exhaust member SL3 at the top of the fourth outer panel component 1321d (upper panel 132A).

[0083] In this example, as shown in FIG. 4, two fans 16 are attached to each of the exhaust port 14 and the intake port 15, thereby promoting the flow of air from the intake port 15 through the internal space SP1 to the exhaust port 14.

[0084] (3-3) Assembly structure of inner panel 13A, the inner panel 131 in this specific example is composed of four inner panel components 1311a to 1311d. The four inner panel components (1311a to 1311d) are a first inner panel component 1311a, a second inner panel component 1311b, a third inner panel component 1311c, and a fourth inner panel component 1311d. The first to fourth inner panel components 1311a to 1311d correspond to the first to fourth outer panel components 1321a to 1321d, respectively. Note that although the fourth inner panel component 1311d was excluded from the components of the inner panel 131 in "(2) Details," it is included in the components of the inner panel 131 in this specific example.

[0085] The first inner panel component 1311a is disposed behind the first outer panel component 1321a and in front of the device body 1A. The second inner panel component 1311b is disposed to the left of the second outer panel component 1321b and on the right side of the device body 1A. The third inner panel component 1311c is disposed to the right of the third outer panel component 1321c and on the left side of the device body 1A. The fourth inner panel component 1311d is disposed in front of the fourth outer panel component 1321d and on the rear side of the device body 1A.

[0086] (3-3-1) Combination of L-shaped and I-shaped elements In this example, the first inner panel component 1311a and the second inner panel component 1311b are integrated as shown in Fig. 4 and are difficult to separate. The first inner panel component 1311a and the second inner panel component 1311b are, for example, a single metal sheet bent into an L shape when viewed from above, or two metal sheets joined together in an L shape, and may be referred to below as "the first inner panel component 1311a and the second inner panel component 1311b configured in an L shape" or simply as "L-shaped elements."

[0087] Each of the third inner panel part 1311c and the fourth inner panel part 1311d is an I-shaped metal plate when viewed from above, and may be referred to below as the "I-shaped third inner panel part 1311c" and the "I-shaped fourth inner panel part 1311d", or simply as the "I-shaped element".

[0088] The L-shaped first and second inner panel components 1311a and 1311b and the I-shaped third inner panel component 1311c are preferably detachable from the device main body 1A to facilitate access to the circuit board 11 inside the device main body 1A. On the other hand, the I-shaped fourth inner panel component 1311d does not have to be detachable because it is located at the rear of the device main body 1A, i.e., in a position where no circuit board is located. For this reason, the I-shaped fourth inner panel component 1311d does not have to be included as a component of the inner panel 131.

[0089] In other words, the inner panel 131 may be composed of two parts: a first inner panel part 1311a and a second inner panel part 1311b configured in an L-shape, and a third inner panel part 1311c configured in an I-shape.

[0090] (3-3-2) Intake and exhaust mechanism for the interior panel 5, the fourth inner panel component 1311d has an intake slit SL1. The intake slit SL1 is an opening or slit that allows outside air to be taken into the intake port 15, and is formed in a position corresponding to the intake slit SL2 of the fourth outer panel component 1321d.

[0091] (3-3-3) Waterproof and dustproof function of the inner panel When such an inner panel 131 is attached to the device main body 1A, the three elements of the first inner panel component 1311a and the second inner panel component 1311b, which are configured in an L-shape, the third inner panel component 1311c, which is I-shaped, and the fourth inner panel component 1311d, which is I-shaped, are joined to each other, thereby realizing waterproofing and dustproofing within the inner panel 131.

[0092] (4) Variations Next, various modified examples will be described. Note that, in the following, explanations of matters common to the embodiment will be omitted or simplified, and differences will be described in detail.

[0093] (4-1) First Modification of Power Conversion Device While the power conversion device 1 in the embodiment has a double-structure housing 13 consisting of an inner panel 131 and an outer panel 132, the power conversion device 1 in this modification has a housing consisting of only the inner panel 131. The housing of this modification, i.e., the inner panel 131, has the same functions as the inner panel 131 in the embodiment, and also has some of the functions of the outer panel 132.

[0094] Part of the function of outer panel 132 that inner panel 131 also has is the function of covering the entire device main body 1A. That is, inner panel 131 of this modified example has a length that covers device main body 1A from the top to the bottom, that is, the same length as outer panel 132, and top panel 133 is attached to the top end of inner panel 131.

[0095] The inner panel 131 of this modified example houses the heat sink 12 and multiple boards 111a to 113b, similar to the inner panel 131 of the embodiment. The multiple boards 111a to 113b are arranged in a circuit space SP2 that includes a first circuit space SP21 between the side surface 123 of the heat sink 12 and the inner panel 131, and a second circuit space SP22 that is a space below the open lower surface 122 of the heat sink 12.

[0096] This modification also makes it possible to ensure heat dissipation performance while enabling high-density mounting on the board.

[0097] (4-2) Second Modification of Power Conversion Device Although the power conversion device 1 in the embodiment includes a cylindrical (chimney-shaped) heat sink 12, the shape of the heat sink 12 may be a shape other than a cylindrical shape. Examples of shapes other than a cylindrical shape include a cylindrical shape or a plate shape in which the upper surface 121 and the lower surface are not open (not hollow).

[0098] The power converter 1 of this modified example includes a plurality of substrates 111a to 113b and a plate-shaped heat sink 12. The plurality of substrates 111a to 113b are arranged in parallel to the plate-shaped heat sink 12.

[0099] Even in this modified example, by adopting a double structure of the inner panel 131 and the outer panel 132, it is possible to ensure waterproof and dustproof performance with the inner panel 131 while improving the design with the outer panel 132.

[0100] (4-3) First Modification Regarding the Relationship Between the Heat Sink and the Inner Panel 11B, the heat sink 12 in this modification extends from the top to the bottom of the inner panel 131. In other words, the open 122121 of the heat sink 12 is located at the top of the inner panel 131, and the open lower surface 122 of the heat sink 12 is located at the bottom of the inner panel 131.

[0101] According to this modified example, by using a heat sink 12 that extends from the top to the bottom of the inner panel 131, the rigidity of the inner panel 131 and, ultimately, the housing 13 consisting of the inner panel 131 and the outer panel 132 can be improved.

[0102] (4-4) Second Modification Regarding the Relationship Between the Heat Sink and the Inner Panel 11C, the vertical length of heat sink 12 in this modification is shorter than the vertical length of inner panel 131. In this modification, duct 137 is provided between the open lower surface 122 of heat sink 12 and the lower part of inner panel 131. Air taken in through intake port 15 passes through the space in duct 137 and internal space SP1 in heat sink 12 and is discharged from exhaust port 14.

[0103] According to this modified example, by providing a duct 137 between the lower surface 122 of the heat sink 12 and the lower part of the inner panel 131, the rigidity of the inner panel 131 and, ultimately, the housing 13 consisting of the inner panel 131 and the outer panel 132 can be improved.

[0104] (4-5) First variant of the inner panel: a combination of an L-shaped element and two I-shaped elements As shown in FIG. 4, the inner panel 131 in the embodiment is constructed by assembling two elements: a first inner panel part 1311a and a second inner panel part 1311b which are configured in an L-shape, and a third inner panel part 1311c which is configured in an I-shape. However, the inner panel 131 may further include a fourth inner panel part 1311d as a constituent element.

[0105] The inner panel 131 in this modified example is formed by assembling three elements: a first inner panel part 1311a and a third inner panel part 1311c which are configured in an L-shape, an I-shaped third inner panel part 1311c, and an I-shaped fourth inner panel part 1311d, as shown in Figure 13A.

[0106] (4-5-1) Packing As shown in FIG. 13A, the inner panel 131 in this modification further includes a plurality of (three in this example) packings 135.

[0107] In the inner panel 131 of this modified example, packings 135 are provided at the joints between three elements: the L-shaped first inner panel component 1311a and third inner panel component 1311c, the I-shaped third inner panel component 1311c, and the I-shaped fourth inner panel component 1311d. The joints between the three elements are the joint between the right end of the first inner panel component 1311a and the front end of the second inner panel component 1311b, the joint between the rear end of the second inner panel component 1311b and the right end of the fourth inner panel component 1311d, and the joint between the rear end of the third inner panel component 1311c and the left end of the fourth inner panel component 1311d. Packings 135 are provided at each of these three joints.

[0108] 13A, a first gasket 135 is provided at the right end of the first inner panel component 1311a at the joint between the right end of the first inner panel component 1311a and the front end of the second inner panel component 1311b. However, the first gasket 135 may also be provided closer to the front end of the second inner panel component 1311b.

[0109] Furthermore, at the joint between the rear end of the second inner panel component 1311b and the right end of the fourth inner panel component 1311d, a second gasket 135 is provided at the rear end of the second inner panel component 1311b. However, the second gasket 135 may also be provided closer to the right end of the fourth inner panel component 1311d.

[0110] Furthermore, at the joint between the rear end of the third inner panel component 1311c and the left end of the fourth inner panel component 1311d, a second gasket 135 is provided at the rear end of the third inner panel component 1311c. However, the third gasket 135 may also be provided closer to the left end of the fourth inner panel component 1311d.

[0111] In the case of the inner panel 131 in the embodiment, the gasket 135 is provided at the joint between the two elements, the first inner panel part 1311a and the second inner panel part 1311b which are configured in an L-shape, and the third inner panel part 1311c which is in an I-shape, i.e., at either the left end part of the first inner panel part 1311a or the front end part of the third inner panel part 1311c.

[0112] According to this configuration, by providing packing 135 at the joints between the multiple elements that make up the inner panel 131 to seal the circuit space SP2, it is possible to improve waterproof and dustproof performance.

[0113] (4-6) Second variant of the inner panel: Combination of three or four I-shaped elements 13B, the inner panel 131 in this modification is configured by assembling four I-shaped elements, that is, inner panel parts 1311a to 1311d. However, of the four I-shaped elements, the fourth inner panel part 1311d may be excluded from the components of the inner panel 131.

[0114] In this modification, the packings 135 are attached to, for example, both the left and right ends of the first inner panel component 1311a and the rear ends of the second and third inner panel components 1311b and 1311c. However, the attachment positions of the four packings 135 here may be changed as appropriate.

[0115] (4-7) Third variant of the inner panel: Combination of U-shaped and I-shaped elements 13C, the inner panel 131 in this modification is configured by assembling first to third inner panel components 1311a to 1311c (U-shaped elements) configured in a U-shape and a fourth inner panel component 1311d (I-shaped element) configured in an I-shape. However, of these U-shaped elements and I-shaped elements, the I-shaped element, i.e., the fourth inner panel component 1311d, may be excluded from the components of the inner panel 131.

[0116] In this modified example, the packings 135 are attached to the rear end portions of the second inner panel component 1311b and the third inner panel component 1311c. However, the attachment positions of the two packings 135 here may be changed as appropriate.

[0117] (4-8) First variant of outer panel: Combination of L-shaped element and two I-shaped elements The outer panel 132 in this modified example is formed by assembling three elements: a first outer panel part 1321a and a third outer panel part 1321c which are configured in an L-shape, a second outer panel part 1321b which is I-shaped, and a fourth outer panel part 1321d which is I-shaped, as shown in Figure 14A.

[0118] Alternatively, the outer panel 132 may be constructed by assembling three elements: a first outer panel part 1321a and a second outer panel part 1321b configured in an L-shape, a third outer panel part 1321c configured in an I-shape, and a fourth outer panel part 1321d configured in an I-shape.

[0119] (4-9) Second variant of outer panel: Combination of four I-shaped elements The outer panel 132 in this modification is configured by assembling four I-shaped outer panel components 1321a to 1321d as shown in FIG. 14B.

[0120] (4-10) Third variant of outer panel: Combination of U-shaped and I-shaped elements The outer panel 132 in this modified example is formed by assembling a first outer panel part 1321a to a third outer panel part 1321c (U-shaped elements) which are configured in a U shape, and an I-shaped fourth outer panel part 1321d (I-shaped element), as shown in Figure 14C.

[0121] (4-11) First modified example of heat dissipation structure 9B, the plurality of substrates 111a to 113b may be distributed over all of the four side surfaces 123a to 123d of the heat sink 12. In this case, the plurality of substrates 111a to 113b further includes a fourth substrate group 114. The fourth substrate group 114 is made up of an upper fourth substrate 114a and a lower fourth substrate 114b.

[0122] (4-12) Second modified example of heat dissipation structure As shown in Fig. 9C, multiple substrates may be arranged on one side surface when viewed from above. In the example of Fig. 9C, two upper second substrates 112a are arranged on the right side surface.

[0123] (4-13) Third and fourth modified examples of heat dissipation structure The plurality of substrates 111a to 113b may be distributed on two of the four side surfaces 123a to 123d of the heat sink 12, as shown in FIG. 9D or FIG. 9E.

[0124] The two side surfaces in the third modified example of the heat dissipation structure are side surfaces that face each other with the heat sink 12 sandwiched between them, as shown in Fig. 9D. The facing side surfaces are, for example, the left and right sides as shown in Fig. 9D, but may also be the front and rear sides. In the example of Fig. 9D, the upper second substrate 112a and the upper third substrate 113a are arranged to face each other with the heat sink 12 sandwiched between them.

[0125] The two side surfaces in the fourth modified example of the heat dissipation structure are two adjacent side surfaces, as shown in FIG. 9E. The two adjacent side surfaces may be two side surfaces perpendicular to each other. For example, the two adjacent side surfaces are the front and left side surfaces as shown in FIG. 9E, but they may also be the front and right side surfaces, or either the left or right side surface and the rear surface. In the example of FIG. 9E, the upper first substrate 111a and the upper second substrate 112a are arranged perpendicular to each other along the two adjacent side surfaces of the heat sink 12, respectively.

[0126] According to this modified example, even if the number of substrates 111a to 113b increases, the heat generated by each of the multiple substrates 111a to 113b distributed on two of the four side surfaces 123a to 123d of the heat sink 12 is dissipated from the two side surfaces into the internal space SP1, thereby ensuring heat dissipation performance and enabling high-density mounting of the substrates 111a to 113b.

[0127] (4-14) Fifth modified example of heat dissipation structure 9F, the heat sink 12 may have a cylindrical shape with circular upper and lower surfaces 121 and 122. In this modification, four upper substrates (first upper substrate 111a to fourth upper substrate 114a) are arranged to face each other across the circular side surface 123 of the heat sink 12 in top view, and four lower substrates (first lower substrate 111b to fourth lower substrate 114b) are arranged below the first upper substrate 111a to fourth upper substrate 114a.

[0128] According to this modification, the heat sink 12 has a cylindrical shape with a single side surface, which makes it easy to increase the number of substrates 111a-113b. Even if the number of substrates 111a-113b increases, the heat generated by each of the substrates 111a-113b distributed across two or more locations on the single side surface of the heat sink 12 is dissipated in different directions from each other toward the internal space SP1 from the two or more locations on the single side surface, thereby ensuring heat dissipation performance and enabling even higher density mounting of the substrates 111a-113b.

[0129] (4-15) Sixth Modification of Heat Dissipation Structure In the embodiment, the cylindrical shape of the heat sink 12 is a rectangular prism-like cylindrical shape, but it may be a rectangular prism-like cylindrical shape other than a rectangular prism. Examples of rectangular prism-like cylindrical shapes other than a rectangular prism include a triangular prism in which the upper surface 121 and the lower surface 122 are triangular, and a hexagonal prism in which the upper surface 121 and the lower surface 122 are hexagonal.

[0130] The cylindrical shape in this modification is a hexagonal prism. In the case of the hexagonal prism-shaped heat sink 12, the plurality of substrates 111a to 113b are distributed and arranged on two or more of the six side surfaces.

[0131] According to this modification, the heat sink 12 has a hexagonal prism shape formed with six side surfaces, which makes it easy to increase the number of substrates 111a-113b. Even if the number of substrates 111a-113b increases, the heat generated by each of the substrates 111a-113b distributed across two or more of the six side surfaces of the heat sink 12 is dissipated from the two or more side surfaces in mutually different directions toward the internal space SP1, thereby ensuring heat dissipation performance and enabling even higher density mounting of the substrates 111a-113b.

[0132] (4-16) Variations of the three sides on which the substrate is placed 9A, in the embodiment, the plurality of substrates 111a to 113b are arranged on the first to third side surfaces 123a to 123c of the heat sink 12, but in this modification, the three side surfaces on which the plurality of substrates 111a to 113b are arranged are the second to fourth side surfaces 123b to 123d. This modification makes it easier to arrange components other than substrates on the first side surface 123a (to use the front side of the device body 1A for purposes other than arranging substrates).

[0133] (4-17) Modified examples of arrangement of multiple heating elements In the embodiment, as shown in Fig. 10A, all of the multiple substrates 111a to 113a arranged around the side surface 123 of the heat sink 12 have the heat-generating circuit 11B, but some of the multiple substrates 111a to 113a may not have the heat-generating circuit 11B. In this modification, as shown in Fig. 10B, of the upper first substrate 111a to upper third substrate 113a around the side surface 123, the upper first substrate 111a does not have the heat-generating circuit 11B.

[0134] (4-18) Variations of the heat dissipation structure and the cooperation between the inner panel and the outer panel 10C, at least some of the plurality of substrates 111a to 113b may be thermally coupled to the inner panel 131 via a heat dissipation member 136. In this modification, the heat dissipation member 136 is made of metal, but may also be made of a material other than metal that has high thermal conductivity.

[0135] In the example of FIG. 10C, of ​​the three substrates arranged around the side surface 123 of the heat sink 12, namely the upper first substrate 111a to the upper third substrate 113a, each of the upper first substrate 111a and the upper second substrate 112a is thermally coupled to the inner panel 131 via the heat dissipation member 136.

[0136] As a result, heat from the heat-generating circuit 11B is transferred not only to the heat sink 12 but also to the inner panel 131 made of sheet metal, improving heat dissipation performance. Specifically, the heat transferred to the inner panel 131 is dissipated into the space between the inner panel 131 and the outer panel 132, and the air heated thereby is discharged to the outside from the exhaust member SL3 (see FIGS. 2 and 3) on the upper part of the outer panel 132. In response, outside air enters the space between the inner panel 131 and the outer panel 132 from the intake slits SL2 (see FIGS. 2 and 3) of the outer panel 132, and an ascending air current is generated in the space between the inner panel 131 and the outer panel 132, thereby cooling the inner panel 131 and ultimately the plurality of boards 111a to 113a.

[0137] (4-19) First to third modified examples of the intake and exhaust mechanism The fan 16 may be provided at either the exhaust port 14 or the intake port 15, as shown in Figures 12A and 12B, or may be provided at neither the exhaust port 14 nor the intake port 15, as shown in Figure 12C.

[0138] In the first modified example of the intake and exhaust mechanism shown in Fig. 12A, fan 16 is provided only in exhaust port 14. In the second modified example of the intake and exhaust mechanism shown in Fig. 12B, fan 16 is provided only in intake port 15. In the third modified example of the intake and exhaust mechanism shown in Fig. 12C, fan 16 is not provided in either exhaust port 14 or intake port 15.

[0139] Ventilation efficiency and heat dissipation performance can be improved even if fan 16 is installed in only one of exhaust port 14 and intake port 15. Furthermore, even if fan 16 is not installed in either exhaust port 14 or intake port 15, ventilation by the rising air current generated in internal space SP1 and heat dissipation to the outside are possible.

[0140] (4-20) Modifications regarding outer panels 12D, the entire outer panel 132 may be composed of an upper panel 132A and a lower panel 132B. The upper panel 132A is the portion of the outer panel 132 that corresponds to the circuit space SP2. The lower panel 132B is the portion of the outer panel 132 that corresponds to the installation space SP3.

[0141] According to this modified example, by removing the lower panel 132B as needed, access to the construction space SP3 is facilitated and construction can be carried out using the construction space SP3, thereby further improving construction ease compared to when the entire outer panel 132 is removed.

[0142] (4-21) Modifications regarding installation of power conversion device Although the power conversion device 1 in the embodiment is a stationary type and is placed vertically during use or installation as shown in Fig. 1 etc., the power conversion device 1 of this modified example is portable and is not necessarily placed vertically, and may be placed, for example, parallel to a horizontal plane (i.e., horizontal placement) or at an angle to a horizontal plane (i.e., diagonal placement). Furthermore, even if the device main body 1A is placed vertically, the heat sink 12 is not necessarily placed so that both bottom surfaces (first main surface 121 and second main surface 122) are positioned above and below in the vertical direction (i.e., vertical placement).

[0143] The power conversion device 1 in the embodiment comprises a plurality of substrates 111a to 113b and a cylindrical heat sink 12 having openings on an upper surface 121 and a lower surface 122, and when viewed from above, the plurality of substrates 111a to 113b are arranged to surround the side surface 123 of the heat sink 12, whereas the power conversion device 1 in this modified example comprises a plurality of substrates 111a to 113b and a cylindrical heat sink 12 having openings on a first main surface 121 and a second main surface 122, and the first main surface 121 and the second main surface 122 face each other along a predetermined direction, and the plurality of substrates 111a to 113b are arranged to surround the side surface 123 of the heat sink 12 when viewed from the predetermined direction.

[0144] In the power converter 1 of this modification, the first main surface 121 and the second main surface 122 of the heat sink 12 are preferably positioned above and below in the vertical direction like the upper surface 121 and the lower surface 122 in the embodiment, but may be positioned front to back or left to right in the horizontal direction, or may be positioned to line up along a straight line inclined with respect to the horizontal plane (hereinafter referred to as an "inclined line"). That is, in this modification, the first main surface 121 and the second main surface 122 face each other along a predetermined direction, and the multiple substrates 111a to 113b are arranged to surround the side surface 123 when viewed from the predetermined direction.

[0145] The heat sink 12 in the embodiment corresponds to a state in which the heat sink 12 in this modified example is arranged so that the first and second main surfaces are the upper surface 121 and the lower surface 122, respectively (i.e., vertically placed). Furthermore, a top view in the embodiment corresponds to a state in which the heat sink 12 in this modified example is placed vertically and the first main surface (upper surface 121) is viewed from the opposite side to the second main surface (lower surface 122) (i.e., from above in the vertical direction, which is a predetermined direction). Furthermore, a side view in the embodiment corresponds to a state in which the heat sink 12 in this modified example is placed vertically and the side surface 123 is viewed from a direction perpendicular to the vertical direction, which is a predetermined direction (i.e., horizontally).

[0146] Furthermore, the upper surface 121 and the lower surface 122 in the embodiments are not limited to two surfaces aligned along a vertical line and perpendicular to the vertical line, but may also be two surfaces aligned along an inclined line and perpendicular to the inclined line (i.e., the upper surface and the lower surface with respect to the vertical component of the inclined line). In this case, the top view corresponds to viewing the upper surface from the opposite side to the lower surface with respect to the vertical component of the inclined line (i.e., diagonally above). Furthermore, the upper and lower (upper and lower) in the embodiments are not limited to above and lower than the vertical line (vertically above and vertically below), but may also be above and lower (diagonally above and diagonally below) with respect to the vertical component of the inclined line.

[0147] (5) Summary A power converter (1) according to a first aspect includes a plurality of substrates (111a-113b) and a cylindrical heat sink (12). The heat sink (12) faces each other along a predetermined direction and includes a first main surface (121) and a second main surface (122), each having an opening, and a side surface (123) sandwiched between the first main surface (121) and the second main surface (122). A circuit (11B) for power conversion is mounted on each of the plurality of substrates (111a-113b). The plurality of substrates (111a-113b) are arranged to surround the side surface (123) when viewed from a predetermined direction. The heat sink (12) dissipates heat generated by each of the circuits (11B) of the plurality of substrates (111a-113b) into an internal space (SP1), which is a space surrounded by the side surface (123).

[0148] According to this aspect, the plurality of substrates (111a-113b) are arranged to surround the side surface (123) of the cylindrical heat sink (12) having openings on the first main surface (121) and the second main surface (122). This allows the heat generated by each circuit (11B) of the plurality of substrates (111a-113b) to be efficiently dissipated from a plurality of portions of the side surface (123) in different directions toward the internal space (SP1) surrounded by the side surface (123) (i.e., while avoiding interference of heat transfer routes between the plurality of substrates). This heats the air in the internal space (SP1), generating an air current that flows through the internal space (SP1) from the second main surface (122) to the first main surface (121) or from the first main surface (121) to the second main surface (122). As a result, the heat in the internal space (SP1) is released to the outside of the internal space (SP1).

[0149] Even if the amount of heat dissipated into the internal space (SP1) increases due to high-density mounting, the heat within the internal space (SP1) is discharged to the outside of the internal space (SP1) due to an increase in the airflow through the internal space (SP1), thereby making it possible to achieve high-density mounting of the substrates (111a-113b) while maintaining heat dissipation performance.

[0150] In the power converter (1) according to the second aspect, in the first aspect, the cylindrical shape is a quadrangular prism-shaped cylindrical shape in which each of the first main surface (121) and the second main surface (122) is rectangular. The plurality of substrates (111a-113b) are distributed and arranged on two or more side surfaces (for example, three side surfaces of the first side surface 123a to the third side surface 123c, or two side surfaces of the first side surface 123a and the second side surface 123b; hereinafter, referred to as "123a-123c; 123a and 123b") of the four side surfaces (first side surface 123a to fourth side surface 123d) including the side surface (123) of the quadrangular prism-shaped cylindrical heat sink (12).

[0151] According to this aspect, since the heat sink (12) has a rectangular cylindrical shape composed of four side surfaces (123a to 123d), it is possible to distribute multiple substrates (111a to 113b) on two or more of the four side surfaces (123a to 123d) (for example, the three side surfaces of the first side surface 123a to the third side surface 123c, or the two side surfaces of the second side surface 123b and the third side surface 123c, etc.), and thus to increase the number of substrates (111a to 113b). Furthermore, even if the number of substrates (111a to 113b) increases, the heat generated by each of the multiple substrates (111a to 113b) distributed over two or more side surfaces (123a to 123c; 123a and 123b) of the heat sink (12) is dissipated from the two or more side surfaces (123a to 123c; 123a and 123b) to the internal space (SP1), thereby ensuring heat dissipation performance and enabling even higher density mounting of the substrates (111a to 113b).

[0152] In the power converter (1) according to the third aspect, in the second aspect, the plurality of substrates (111a to 113b) are distributed and arranged on three side surfaces (123a to 123c) of the four side surfaces (123a to 123d).

[0153] According to this aspect, even if the number of substrates (111a to 113b) increases, the heat generated by each of the multiple substrates (111a to 113b) distributed on three of the four side surfaces (123a to 123d) of the heat sink (12) is dissipated from the three side surfaces (123) to the internal space (SP1), thereby ensuring heat dissipation performance and enabling even higher density mounting of the substrates (111a to 113b).

[0154] In a power conversion device (1) according to a fourth aspect, in the third aspect, the plurality of substrates (111a-113b) includes a first substrate group (111), a second substrate group (112), and a third substrate group (113). The first substrate group (111) includes one or more substrates (111a, 111b) arranged on a first side surface (123a) of four side surfaces (123a-123d). The second substrate group (112) includes one or more substrates (112a, 112b) arranged on a second side surface (123b) perpendicular to the first side surface (123a) of the four side surfaces (123a-123d). The third substrate group (113) includes one or more substrates (113a, 113b) arranged on a third side (123c) of the four side surfaces (123a to 123d), the third side surface (123c) being perpendicular to the first side surface (123a) and parallel to the second side surface (123b).

[0155] According to this embodiment, the heat generated by the first substrate group (111) is dissipated from the first side (123a) of the heat sink (12), the heat generated by the second substrate group (112) is dissipated from the second side (123b) of the heat sink (12), and the heat generated by the third substrate group (113) is dissipated from the third side (123c) of the heat sink (12) into the internal space (SP1) in directions that face or intersect with each other, thereby improving heat dissipation performance.

[0156] The power converter (1) according to a fifth aspect is the power converter (1) of any one of the first to fourth aspects, further including a housing (at least an inner panel 131: in the embodiment, the inner panel 131 and the outer panel 132, but the inner panel 131 alone may be used). The housing houses a heat sink (12) and a plurality of boards (111a to 113b). The plurality of boards (111a to 113b) are arranged in a circuit space (SP2). The circuit space (SP2) includes a space (SP21) between a side surface (123) of the heat sink (12) and the housing (inner panel 131).

[0157] According to this aspect, by arranging the plurality of substrates (111a to 113b) in the circuit space (SP2) surrounded by the housing (inner panel 131), it is possible to improve waterproofing and dustproofing.

[0158] In a power converter (1) according to a sixth aspect, in the fifth aspect, the heat sink (12) is arranged so that the first main surface (1221) is the upper surface (121) and the second main surface (122) is the lower surface (122). The housing (13: for example, an inner panel 131) extends downward below the lower surface (122) of the heat sink (12). The circuit space (SP2) includes a first circuit space (SP21) and a second circuit space (SP22). The first circuit space (SP21) is a space around the side surface (123) of the heat sink (12) in a side view. The second circuit space (SP22) is a space below the lower surface (122) of the heat sink (12) in a side view. Some of the multiple substrates (111a to 113b) (upper first substrate 111a to upper third substrate 113a) are arranged in the first circuit space (SP21), and the remaining some (lower first substrate 111b to lower third substrate 113b) are arranged in the second circuit space (SP21).

[0159] According to this embodiment, the first main surface (121) is the upper surface (121), the second main surface (122) is the lower surface (122), and an ascending air current is generated in the internal space (SP1) flowing from the lower surface (122) to the upper surface (121). As a result, heat in the internal space (SP1) is efficiently discharged to the outside of the internal space (SP1). In addition, the circuit space (SP2) includes a first circuit space (SP21) around the side surface (123) of the heat sink (12) and a second circuit space (SP22) below the lower surface (122) of the heat sink (12). This makes it possible to achieve further density while avoiding mutual interference of heat transferred from the multiple substrates (111a-113b) to the heat sink (12).

[0160] In the power converter (1) according to the seventh aspect, in the fifth aspect, the heat sink (12) is arranged so that the first main surface (1221) is the upper surface (121) and the second main surface (122) is the lower surface (122). The upper surface (121) of the heat sink (12) is located at an upper part of the housing (13: for example, the inner panel 131). The lower surface (122) of the heat sink (12) is located at a lower part of the housing (13: for example, the inner panel 131).

[0161] According to this aspect, by using the heat sink (12) extending from the top to the bottom of the housing (13: for example, the inner panel 131), it is possible to improve the rigidity of the housing (13: for example, the inner panel 131).

[0162] The power conversion device (1) according to an eighth aspect is the seventh or eighth aspect, further including an exhaust port (14) and an intake port (15). The exhaust port (14) is provided above the upper surface (121) of the heat sink (12) and exhausts air from the internal space (SP1) to the outside of the housing (13: for example, the inner panel 131 and the outer panel 132). The intake port (15) is provided below the lower surface (122) of the heat sink (12) and draws air from the outside of the housing (13: for example, the inner panel 131 and the outer panel 132) into the internal space (SP1).

[0163] According to this aspect, air in the internal space (SP1) is discharged to the outside of the housing (13: for example, the inner panel 131 and the outer panel 132) through the exhaust port (14), while air outside the housing (13: for example, the inner panel 131 and the outer panel 132) is taken into the internal space (SP1) through the intake port (15), thereby enabling ventilation to be performed by utilizing the rising of air in the internal space (SP1) that has been heated by heat radiation. Furthermore, by arranging the exhaust port (14) and the intake port (15) at positions that sandwich the heat sink (12) from above and below, efficient ventilation can be achieved regardless of the relative length of the heat sink (12) with respect to the housing (13: for example, the inner panel 131 and the outer panel 132).

[0164] The power converter (1) according to a ninth aspect is the power converter (1) of the eighth aspect, further including a fan (16). The fan (16) is provided in at least one of the exhaust port and the intake port.

[0165] According to this aspect, it is possible to improve ventilation efficiency and, in turn, heat dissipation performance.

[0166] In the power converter (1) according to the tenth aspect, in the second aspect, the plurality of substrates (111a to 113b) are distributed and arranged on two of the four side surfaces (123a to 123d).

[0167] According to this aspect, even if the number of substrates (111a to 113b) increases, the heat generated by each of the multiple substrates (111a to 113b) distributed on two of the four sides of the heat sink (12) is dissipated from the two sides into the internal space (SP1), thereby ensuring heat dissipation performance and enabling high-density mounting of the substrates (111a to 113b).

[0168] In a power converter (1) according to an eleventh aspect, in the fourth aspect, the heat sink (12) has one or more heat dissipation fins (124) arranged in the internal space (SP1) parallel to the first side surface (123a). A pair of ends of each of the one or more heat dissipation fins (124) are thermally coupled to the second side surface (123b) and the third side surface (123c), respectively.

[0169] According to this embodiment, one or more heat dissipation fins (124) arranged in parallel to the first side surface (123a) in the internal space (SP1) promote heat dissipation without interfering with the airflow from bottom to top, thereby improving heat dissipation. Furthermore, one or more heat dissipation fins (124) are thermally coupled to the second side surface (123b) and the third side surface (123c), thereby improving heat dissipation capability (compared to, for example, a case in which one or more heat dissipation fins (124) are arranged in parallel to each of the second side surface 123b and the third side surface 123c and are thermally coupled to the first side surface 123a and the fourth side surface 123d on which no substrate is arranged).

[0170] In the power converter (1) according to the twelfth aspect, in the eleventh aspect, the width of each of the second side surface (123b) and the third side surface (123c) is greater than the width of the first side surface (123a).

[0171] According to this embodiment, the width of each of the second side surface (123b) and the third side surface (123c) is larger than the width of the first side surface (123a), which facilitates high-density mounting (compared to, for example, a case where the widths of the second side surface 123b and the third side surface 123c are smaller than the width of the first side surface 123a). [Explanation of symbols]

[0172] 1 Power conversion device 111 First substrate group 112 Second substrate group 113 Third board group 11B Heat generating circuit 12 Heat sink 121 Top surface (first principal surface) 122 Bottom surface (2nd principal surface) 123 Side 123a 1st side 123b Second side 123c 3rd side 123d 4th side 124 Heat dissipation fin 13. Cabinet 131 Inner Panel 1311 Inner panel parts 1311a First inner panel part 1311b Second inner panel part 1311c Third inner panel part 1311d 4th inner panel part 132 outer panel 1321 Outer panel parts 1321a First outer panel part 1321b Second outer panel part 1321c Third outer panel part 1321d 4th outer panel part 132A Top Panel 132B Lower Panel 135 Gasket 14 Exhaust port 15 Air intake 16 Fans 17 Insulation sheet 18 Installation parts (charging cable) SP1 interior space SP2 circuit space SP21 1st circuit space SP22 2nd circuit space SP3 construction space

Claims

1. a plurality of substrates on which circuits for power conversion are mounted; a cylindrical heat sink including a first main surface and a second main surface facing each other along a predetermined direction and each having an opening, and a side surface sandwiched between the first main surface and the second main surface; the plurality of substrates are arranged to surround the side surface when viewed from the predetermined direction, the heat sink dissipates heat generated by the circuits of each of the plurality of boards into an internal space that is a space surrounded by the side surfaces. Power conversion device.

2. the cylindrical shape is a quadrangular prism-shaped cylindrical shape in which the first main surface and the second main surface are each quadrangular, the plurality of substrates are distributed and arranged on two or more of four side surfaces of the heat sink having a rectangular prism-like cylindrical shape, including the side surface; The power conversion device according to claim 1 .

3. the plurality of substrates are distributed and arranged on three of the four side surfaces; The power conversion device according to claim 2 .

4. The plurality of substrates include: a first substrate group including one or more substrates disposed on a first side surface among the four side surfaces; a second substrate group including one or more substrates arranged on a second side surface of the four side surfaces that is perpendicular to the first side surface; a third substrate group including one or more substrates arranged on a third side surface, which is perpendicular to the first side surface and parallel to the second side surface, among the four side surfaces; The power conversion device according to claim 3 .

5. a housing that houses the heat sink and the plurality of substrates; the plurality of substrates are arranged in a circuit space including a space between the side surface of the heat sink and the housing; The power conversion device according to claim 1 .

6. the heat sink is disposed such that the first main surface is an upper surface and the second main surface is a lower surface, the housing extends downward below the lower surface of the heat sink; The circuit space is a first circuit space around the side surface of the heat sink in a side view; a second circuit space below the lower surface of the heat sink in a side view, a part of the plurality of substrates is disposed in the first circuit space, and a part of the remaining substrates is disposed in the second circuit space; The power conversion device according to claim 5 .

7. the heat sink is disposed such that the first main surface is an upper surface and the second main surface is a lower surface, the upper surface of the heat sink is located on the upper part of the housing; The lower surface of the heat sink is located below the housing. The power conversion device according to claim 5 .

8. an exhaust port provided above the upper surface of the heat sink and configured to exhaust air from the internal space to the outside of the housing; an air intake port provided below the lower surface of the heat sink and adapted to draw air from outside the housing into the internal space; The power conversion device according to claim 6 or 7.

9. The air conditioner further includes a fan provided in at least one of the exhaust port and the intake port. The power conversion device according to claim 8 .

10. The plurality of substrates are distributed and arranged on two of the four side surfaces. The power conversion device according to claim 2 .

11. the heat sink has one or more heat dissipation fins arranged in the internal space parallel to the first side surface, Each of the one or more heat dissipation fins has a pair of ends thermally coupled to the second side surface and the third side surface, respectively. The power conversion device according to claim 4.

12. The width of each of the second side surface and the third side surface is greater than the width of the first side surface. The power converter according to claim 11.

Images