Electric connection unit

Abstract

To provide an electric connection unit capable of attaining an improvement of thermal characteristics.SOLUTION: An electric connection unit comprises a plurality of circuit configuration bodies and a support member which supports the plurality of circuit configuration bodies. Each of the circuit configuration bodies includes a plurality of electronic components, a bus bar which electrically connects the plurality of electronic components, and an insulating base member which holds the bus bar. In a case where a direction in which the plurality of electronic components and the base member are opposed is defined as a first direction, each base member includes an opposite region which is opposed with the plurality of electronic components in a view in the first direction, and is fixed to the support member by a plurality of fixing parts which is disposed while being separated so as to enclose the outside of the opposite region in a view in the first direction.SELECTED DRAWING: Figure 7

Description

[Technical Field]

[0001] SUMMARY OF THE INVENTION An embodiment of the present invention relates to an electrical connection unit. [Background technology]

[0002] 2. Description of the Related Art An electrical connection unit is known that has a housing that houses electronic components and a bus bar attached to the housing in an upright position. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] Japanese Patent Application Publication No. 2024-037492 Summary of the Invention [Problem to be solved by the invention]

[0004] Meanwhile, electrical connection units are expected to have improved thermal properties.

[0005] One embodiment provides an electrical connection unit that can provide improved thermal performance. [Means for solving the problem]

[0006] In one embodiment, the electrical connection unit includes a plurality of circuit assemblies and a support member supporting the plurality of circuit assemblies. Each circuit assembly includes a plurality of electronic components, a bus bar electrically connecting the plurality of electronic components, and an insulating base member that holds the bus bar. When the direction in which the plurality of electronic components and the base member face each other is defined as a first direction, each base member has a facing region that faces the plurality of electronic components when viewed from the first direction, and is fixed to the support member by a plurality of fixing portions that are separately arranged so as to surround the outside of the facing region when viewed from the first direction. [Effects of the Invention]

[0007] According to one embodiment, the thermal characteristics of the electrical connection unit can be improved. [Brief explanation of the drawings]

[0008] [Figure 1] FIG. 2 is a cross-sectional view showing the electrical connection unit according to the embodiment. [Figure 2] FIG. 2 is a perspective view illustrating a main body of the embodiment. [Figure 3] FIG. 2 is a perspective view illustrating a subunit according to the embodiment. [Figure 4] FIG. 2 is a partially exploded perspective view of a subunit according to the embodiment. [Figure 5] FIG. 2 is a perspective view showing the wiring board according to the embodiment. [Figure 6] FIG. 2 is a partially exploded perspective view of the wiring board according to the embodiment. [Figure 7] FIG. 2 is a plan view showing the wiring board according to the embodiment. [Figure 8] FIG. 2 is a partially exploded perspective view of the connection unit according to the embodiment. [Figure 9] FIG. [Figure 10] 8 is a cross-sectional view of the structure shown in FIG. 7 taken along line AA. [Figure 11] FIG. 8 is a cross-sectional view of the structure shown in FIG. 7 taken along line BB. [Figure 12] FIG. 6 is a cross-sectional view illustrating a heat dissipation path related to the fixing portion of the embodiment. [Figure 13] FIG. 10 is a cross-sectional view illustrating a heat dissipation path in a modified example of the embodiment. [Figure 14] 5A and 5B are cross-sectional views illustrating a structure for absorbing thermal expansion / contraction related to a fixing portion of the embodiment. [Figure 15] 5A and 5B are cross-sectional views showing the operation of the absorbent structure of the embodiment. DETAILED DESCRIPTION OF THE INVENTION

[0009] Hereinafter, embodiments will be described with reference to the drawings. In the following description, components having the same or similar functions will be assigned the same reference numerals. Duplicate descriptions of those components may be omitted. Note that the configurations described below do not limit the scope of the embodiments.

[0010] In this disclosure, terms are defined as follows: "Connection" is not limited to mechanical connection and may include electrical connection. In other words, "connection" is not limited to direct connection between two elements to be connected, but may include connection between two elements via another element interposed therebetween. "Containment" is not limited to containment of the entire component, but may include containment of only a portion of the component (with the remaining portion of the component protruding). "Facing" means that virtual projections of two objects overlap when viewed from a specific direction. In other words, "facing" is not limited to two objects directly facing each other, but may include cases where two objects face each other with another component interposed between them. "Parallel," "orthogonal," or "same" may include "approximately parallel," "approximately perpendicular," or "approximately the same," respectively.

[0011] In the present disclosure, the +X direction, the −X direction, the +Y direction, the −Y direction, the +Z direction, and the −Z direction are defined as follows: The +X direction is the direction from the first end 80e1 to the second end 80e2 of the metal plate 80 (described later) (see FIG. 8 ). The −X direction is the direction opposite to the +X direction. Hereinafter, when there is no need to distinguish between the +X direction and the −X direction, they will simply be referred to as the “X direction.” The +Y direction and the −Y direction are directions that intersect (e.g., are perpendicular to) the X direction. The +Y direction is the direction from the third end 80e3 to the fourth end 80e4 of the metal plate 80 (described later) (see FIG. 8 ). The −Y direction is the direction opposite to the +Y direction. Hereinafter, when there is no need to distinguish between the +Y direction and the −Y direction, they will simply be referred to as the “Y direction.” The +Z direction and the −Z direction are directions that intersect (e.g., are perpendicular to) the X direction and the Y direction. The +Z direction is the direction from the metal plate 80 described later toward the main body portion MU (see FIG. 1). The -Z direction is the direction opposite to the +Z direction. Hereinafter, when there is no need to distinguish between the +Z direction and the -Z direction, they will simply be referred to as the "Z direction."

[0012] In the following, when there is no distinction between the X direction and the Y direction, they may be referred to as the "horizontal direction." In the following, the Z direction may be referred to as the "vertical direction." In addition, in the following, the +Z direction side may be referred to as "up" and the -Z direction side may be referred to as "down." However, these expressions are used for the convenience of explanation and do not limit the direction of gravity of the electrical connection unit 1 (the installation posture of the electrical connection unit 1).

[0013] (Embodiment) <1. Configuration of the electrical connection unit> FIG. 1 is a cross-sectional view showing an electrical connection unit 1 according to an embodiment. The electrical connection unit 1 is an in-vehicle device mounted on a vehicle such as an EV (Electric Vehicle), an HEV (Hybrid Electric Vehicle), or a PHEV (Plug-in Hybrid Electric Vehicle). The electrical connection unit 1 may also be referred to as an "electrical connection box" or a "junction box." However, the electrical connection unit 1 is not limited to being a box-shaped device.

[0014] The electrical connection unit 1 includes, for example, a main body MU, a metal plate (support member, metal member) 80, an insulating sheet 91 (see FIG. 8), a plurality of heat transfer members 92, and an insulating cover 93.

[0015] <2. Main body> First, the main body MU will be described. FIG. 2 is a perspective view illustrating the main body unit MU. The main body unit MU is a portion that performs the main function of the electrical connection unit 1 (e.g., switching the electrical connection state or overcurrent protection). In this embodiment, the main body unit MU is divided into multiple subunits SU. The main body unit MU is formed by connecting multiple subunits SU. In this embodiment, the main body unit MU has three subunits SU (subunits SUX, SUY, and SUZ). Each subunit SU may be referred to as a "circuit component." One of the circuit components SUX, SUY, and SUZ is an example of a "first circuit component." Another of the circuit components SUX, SUY, and SUZ is an example of a "second circuit component." Each subunit SU is supported by an upper surface 81a (see FIG. 8) of a flat portion 81 of the metal plate 80. The upper surface 81a of the flat portion 81 serves as a support surface that supports the three subunits SU via fixing portions 52 and 82, which will be described later.

[0016] The subunit SUX has a first electrical function. The subunit SUX includes, for example, a plurality of electronic components 10X and a first routing board (mounting member) 40X. The plurality of electronic components 10X are electrically connected to the first routing board 40X. The planar portion 51 of the first routing board 40X is disposed along (parallel to) the upper surface 81a of the planar portion 81 of the metal plate 80. The upper surface 51c (the surface opposite the metal plate 80, see FIG. 8 ) of the planar portion 51 of the first routing board 40X serves as a component mounting surface on which the plurality of electronic components 10X are mounted. In the present disclosure, “mounting” is not limited to cases where the electronic components 10 are directly fixed, but also includes cases where the electronic components 10 are fixed via another component (e.g., a connecting component 20). The component mounting surface is an example of a “base surface.” An upper surface 51c (component mounting surface, base surface) of the first wiring board 40X is formed by, for example, a first surface 51a of a flat portion 51 of a base plate 41 described below and the upper surface of a bus bar 42. A circuit component mounting area 51d (see FIG. 7) on which a plurality of electronic components 10X are mounted is formed on the component mounting surface. The circuit component mounting area 51d is a portion that faces the plurality of electronic components 10X when viewed from the Z direction. The circuit component mounting area 51d is an example of a "facing area."

[0017] The circuit component mounting area 51d has a rectangular shape that is, for example, slightly smaller than the rectangular flat surface portion 51 when viewed from a normal direction (Z direction) of the areas 51c, 81a of each flat surface portion 51, 81. The circuit component mounting area 51d has a rectangular shape. Fixing portions 52 for fixing the subunit SUX to the metal plate 80 are arranged at the four corners (tops) of the rectangular circuit component mounting area 51d. Each fixing portion 52 is arranged to surround the outside of the circuit component mounting area 51d when viewed from the Z direction.

[0018] The subunit SUY has a second electrical function. The second function is different from the first function. The subunit SUY includes, for example, a plurality of electronic components 10Y and a second routing board (mounting member) 40Y. The plurality of electronic components 10Y are electrically connected to the second routing board 40Y. The flat portion 51 of the second routing board 40Y is arranged along (parallel to) the upper surface 81a of the flat portion 81 of the metal plate 80. A region 51c (the surface opposite the metal plate 80) of the second routing board 40Y is defined as a component mounting surface on which the plurality of electronic components 10Y are mounted. The region 51c (component mounting surface, base surface) of the second routing board 40Y is formed, for example, by a first surface 51a of the flat portion 51 of the base plate 41 described below and the upper surface of the bus bar 42. A circuit component mounting region 51d on which the plurality of electronic components 10Y are mounted is formed on the component mounting surface. The circuit component mounting region 51d is a portion that faces the plurality of electronic components 10Y when viewed from the Z direction. The circuit component mounting region 51d is an example of a "facing region."

[0019] The circuit component mounting area 51d has a rectangular shape that is slightly smaller than the rectangular flat surface portion 51 when viewed from a normal direction (Z direction) of the areas 51c, 81a of each flat surface portion 51, 81. The circuit component mounting area 51d is rectangular. Fixing portions 52 for fixing the subunit SUY to the metal plate 80 are arranged at the four corners (tops) of the rectangular circuit component mounting area 51d. Each fixing portion 52 is arranged to surround the outside of the circuit component mounting area 51d when viewed from the Z direction.

[0020] The subunit SUZ has a third electrical function. The third function is different from the first and second functions. The subunit SUZ includes, for example, a plurality of electronic components 10Z and a third routing board (mounting member) 40Z. The plurality of electronic components 10Z are electrically connected to the third routing board 40Z. The planar portion 51 of the third routing board 40Z is arranged along (parallel to) the upper surface 81a of the planar portion 81 of the metal plate 80. A region 51c (the surface opposite the metal plate 80) of the third routing board 40Z serves as a component mounting surface on which the plurality of electronic components 10Z are mounted. The region 51c (component mounting surface, base surface) of the third routing board 40Z is formed, for example, by a first surface 51a of the planar portion 51 of the base plate 41 described below and the upper surface of the bus bar 42. A circuit component mounting region 51d on which the plurality of electronic components 10Z are mounted is formed on the component mounting surface. The circuit component mounting region 51d is a portion that faces the plurality of electronic components 10Z when viewed from the Z direction. The circuit component mounting region 51d is an example of a "facing region."

[0021] The circuit component mounting area 51d has a rectangular shape that is slightly smaller than the rectangular flat surface portion 51 when viewed from a normal direction to the areas 51c, 81a of each flat surface portion 51, 81. The circuit component mounting area 51d is rectangular. Fixing portions 52 for fixing the subunit SUZ to the metal plate 80 are arranged at the four corners (tops) of the rectangular circuit component mounting area 51d. The fixing portions 52 are arranged to surround the outside of the circuit component mounting area 51d when viewed from a normal direction to the areas 51c, 81a of each flat surface portion 51, 81.

[0022] In this embodiment, the three subunits SUX, SUY, and SUZ are arranged side by side in the X direction. For example, the subunit SUX is arranged on the +X direction side of the subunit SUY. The subunits SUX and SUY are electrically connected via a plurality of coupling bus bars 75 that extend between the first routing board 40X and the second routing board 40Y. On the other hand, the subunit SUZ is arranged on the -X direction side of the subunit SUY. The subunits SUZ and SUY are electrically connected via a plurality of coupling bus bars 75 that extend between the third routing board 40Z and the second routing board 40Y. The coupling bus bars 75 are arranged on the opposite side of the metal plate 80 from the plurality of subunits SU.

[0023] In this embodiment, the three wiring boards 40X, 40Y, and 40Z included in the three subunits SUX, SUY, and SUZ are arranged on the same plane. In other words, the three wiring boards 40X, 40Y, and 40Z are arranged at the same height in the Z direction. As a result, the three wiring boards 40X, 40Y, and 40Z form one large wiring board 40M.

[0024] In this embodiment, the three subunits SUX, SUY, and SUZ have the same or similar basic structures. Therefore, the following detailed description will focus on one subunit SU as a representative. Hereinafter, when there is no need to distinguish between subunits SUX, SUY, and SUZ, they will simply be referred to as "subunits SU." Furthermore, when there is no need to distinguish between electronic components 10X, 10Y, and 10Z, they will simply be referred to as "electronic component 10." Furthermore, when there is no need to distinguish between first routing board 40X, second routing board 40Y, and third routing board 40Z, they will simply be referred to as "routing board 40."

[0025] Note that, instead of the above example, the main body MU does not have to be divided into multiple subunits SU. That is, the main body MU may be formed by multiple electronic components 10 and one wiring board 40. Furthermore, the two or more subunits SU are not limited to subunits SU having different functions, and may be subunits SU having the same function.

[0026] In this embodiment, for example, a plurality of subunits (circuit assemblies) SU having different heat generation timings (heat generation periods) are exemplified. For example, when a vehicle equipped with the electrical connection unit 1 is running (discharging), the circuit assemblies SUX and SUY generate heat. On the other hand, when the vehicle is being charged, the circuit assemblies SUZ generate heat. The synthetic resin portion (wiring board 40), which expands due to heat generated by the circuit components SUX, SUY when the vehicle is running, is fixed to the metal plate 80 around the circuit components SUX, SUY. This prevents the expansion / warping of the synthetic resin portion of the circuit components SUX, SUY from acting as thermal stress on the synthetic resin portion of the circuit component SUZ. On the other hand, the synthetic resin portion (wiring board 40), which expands due to the heat generated by the circuit component SUZ when the vehicle is being charged, is fixed to the metal plate 80 around the periphery of the circuit board SUZ. This prevents the expansion / warping of the circuit component SUZ from acting as thermal stress on the synthetic resin portions of the circuit components SUX and SUY.

[0027] As a result of the above, it is possible to reduce the number of times that thermal stress acts on the synthetic resin portion of each circuit assembly SU, thereby improving the life of each synthetic resin portion. The plurality of circuit components 40 that generate heat at different timings may be circuit components for switching charging voltages (400V / 800V).

[0028] <3. Subunit structure> Next, the configuration of the subunit SU will be described. Fig. 3 is a perspective view illustrating the subunit SU. Fig. 4 is a perspective view showing the subunit SU partially exploded. The subunit SU includes, for example, a plurality of electronic components 10, a plurality of connection components 20 for component connection, a plurality of connection components 30 for external connection, and a wiring board 40. The connection components 20 and 30 are members that form a vertical current path. The connection components 20 and 30 may also be referred to as "vertical wiring members."

[0029] <3.1 Electronic components and connecting parts> First, the electronic component 10 and the connecting component 20 for connecting the components will be described. The electronic component 10 is an electronic component that is installed in the subunit SU according to the functions required. The electronic component 10 is, for example, a connector, a fuse, a relay (e.g., a mechanical relay or a semiconductor relay), a capacitor, a branching component, various sensors (e.g., a current sensor or a voltage sensor), an electronic control unit, or an electronic component unit that combines two or more of these. Note that the type of electronic component 10 is not limited to the above example. The electronic component 10 is, for example, a heat-generating component that generates heat when power is applied. Below, a first type electronic component 10M and a second type electronic component 10N will be described as examples of the electronic component 10.

[0030] The connection component 20 is a component that electrically connects the electronic component 10 and the wiring board 40. The connection component 20 forms part of the current path in the subunit SU. The connection component 20 is made of metal (for example, copper or a copper alloy). The connection component 20 may also be referred to as a "metal component." Below, a first type connection component 20M and a second type connection component 20N will be described as examples of the connection component 20.

[0031] <3.1.1 Type 1 Electronic Components> The first type electronic component 10M is an electronic component in which a plurality of terminals 13 are arranged side by side at one end of the electronic component 10M. The electronic component 10M has, for example, a rectangular parallelepiped component main body 12, a plurality of terminals 13, and a plurality of mounting portions 14.

[0032] (Component body) The component body 12 is a part that performs the main function of the electronic component 10M. For example, if the electronic component 10M is a relay, the component body 12 includes a switching part (e.g., a contact part) that switches between a conductive state and a non-conductive state. For example, if the electronic component 10M is a fuse, the component body 12 includes a fusing part that melts when an overcurrent flows. For example, if the electronic component 10M is a capacitor, the component body 12 includes a part that stores electric charge.

[0033] The component body 12 houses components in an outer shell (case) that forms most of the outer shape of the electronic component 10M. The case is made of, for example, synthetic resin and has insulating properties. The component body 12 has an insulating rib 11a that protrudes in a horizontal direction (for example, the X direction) and extends in the Z direction. The insulating rib 11a is, for example, plate-shaped and extends along the horizontal direction (for example, the X direction) and the Z direction. The insulating rib 11a extends, for example, over the entire length of the component body 12 in the Z direction. The insulating rib 11a is arranged between multiple terminals 13 (terminals 13A and 13B, described below). The insulating rib 11a electrically insulates the terminals 13A and 13B. In this embodiment, a portion of the insulating rib 11a is arranged between first portions 21 (described below) of two connecting parts 20M connected to the electronic component 10M. The insulating rib 11a electrically insulates the first portions 21 of the two connection parts 20M connected to the electronic component 10M.

[0034] (Terminal) Terminals 13 are electrical connection portions exposed to the outside of component body 12. Terminals 13 are electrically connected to components inside the case. In this embodiment, electronic component 10M includes terminals 13A and 13B as the multiple terminals 13. One of terminals 13A and 13B is a positive terminal. The other of terminals 13A and 13B is a negative terminal.

[0035] In this embodiment, terminals 13A and 13B are provided at one end of electronic component 10M in the horizontal direction (e.g., the X direction). Terminals 13A and 13B are arranged side by side in the horizontal direction (e.g., the Y direction). Each terminal 13 has a mounting hole (not shown) to which a fastening member 71 (e.g., a screw or a bolt) described later is attached. The mounting hole of each terminal 13 opens in the horizontal direction (e.g., the X direction). The inner peripheral surface of the mounting hole of each terminal 13 has a threaded groove.

[0036] (Mounting part) Mounting portion 14 is a portion for fixing electronic component 10M. Mounting portion 14 has mounting holes (unnumbered) to which fastening members 112 (e.g., screws or bolts, see FIG. 8) described later are attached. The mounting holes are open in the Z direction. The mounting holes are insertion holes through which fastening members 112 are passed. The destinations to which mounting portion 14 is fixed will be described later.

[0037] <3.1.2 Type 1 connection parts> The first type connecting part 20M is a part that electrically connects the first type electronic component 10M and the wiring board 40. In this embodiment, the connecting part 20M electrically connects the electronic component 10M and a bus bar 42 (see FIG. 5) included in the wiring board 40. The connecting part 20M has, for example, a first portion 21 that rises above the wiring board 40 and a second portion 22 that is arranged along the wiring board 40.

[0038] (Part 1) The first portion 21 of the connecting part 20M is a portion that is connected to the terminal 13 of the electronic component 10M. The first portion 21 is a plate-like or rectangular parallelepiped portion that extends in the Z direction. The first portion 21 extends in the Z direction along one end (e.g., an end in the X direction) of the electronic component 10M. The first portion 21 is an upright portion that stands in the Z direction relative to the wiring board 40 (e.g., relative to a bus bar 42 described below). The first portion 21 is adjacent to the electronic component 10M in the horizontal direction (e.g., the X direction). For example, the first portion 21 is adjacent to the terminal 13 of the electronic component 10M in the horizontal direction (e.g., the X direction) and is connected to the terminal 13 of the electronic component 10M from the horizontal direction (e.g., the X direction). The first part 21 of the connecting part 20M is physically and electrically connected to the terminal 13 of the electronic part 10M by inserting a fastening member 71 (e.g., a screw or bolt) into an attachment hole (not shown) and screwing and tightening this fastening member into the attachment hole of the terminal 13 of the electronic part 10M.

[0039] (Second part) The second portion 22 of the connecting part 20M is a portion that is connected to the bus bar 42 (see FIG. 5). The second portion 22 protrudes horizontally (e.g., in the X direction) from the end of the first portion 21 on the -Z direction side. The second portion 22 is a plate portion that extends horizontally. The second portion 22 is adjacent to (overlaps with) the bus bar 42 in the Z direction and is connected to the bus bar 42 from the Z direction. A fastening member 43 (e.g., a screw or bolt, see FIG. 5) that protrudes from the bus bar 42 in the +Z direction passes through the second portion 22. An engaging member 44 (e.g., a nut, see FIG. 3) is screwed and tightened onto the fastening member 43 that passes through the second portion 22, thereby physically and electrically connecting the second portion 22 to the bus bar 42. In this embodiment, the first portion 21 and the second portion 22 form an L-shaped, single piece connecting part 20M.

[0040] <3.1.3 Second type electronic components> The second type electronic component 10N is an electronic component in which two terminals 13 are arranged separately at both horizontal ends of the electronic component 10N. The electronic component 10N has, for example, a component main body 12 and a plurality of terminals 13. Note that among the components of the electronic component 10N, components that have the same function as the electronic component 10M are assigned the same reference numerals. In this case, in the description of the electronic component 10N, "electronic component 10M" can be read as "electronic component 10N" in the above description of the electronic component 10M.

[0041] In electronic component 10N, terminals 13A and 13B are arranged separately at both ends of electronic component 10N in the horizontal direction (e.g., the X direction). Each terminal 13 has a mounting hole (not shown) to which a fastening member 72 (e.g., a screw or a bolt) described below is attached. The mounting hole of each terminal 13 opens in the Z direction. For example, the mounting hole of each terminal 13 is an insertion hole through which the fastening member 72 is passed.

[0042] <3.1.4 Second type of connecting parts> The second type connecting part 20N is a part that electrically connects the second type electronic component 10N to the wiring board 40. In this embodiment, the connecting part 20N electrically connects the electronic component 10N to a bus bar 42 (see FIG. 5) included in the wiring board 40. The connecting part 20N has, for example, a first part 21, a second part 22, and a third part 23.

[0043] (Part 1) The first portion 21 of the connection part 20N is a portion connected to the terminal 13 of the electronic component 10N. The first portion 21 is a rectangular parallelepiped portion extending in the Z direction. The first portion 21 is an upright portion that stands in the Z direction relative to the wiring board 40 (e.g., relative to the bus bar 42). The first portion 21 is adjacent to (overlaps with) the terminal 13 of the electronic component 10N in the Z direction and is connected to the terminal 13 of the electronic component 10N from the Z direction. The first portion 21 of the connection part 20N has a mounting hole (not shown) to which a fastening member 72 (e.g., a screw or bolt) described below is attached. The mounting hole of the connection part 20N opens upward and has a threaded groove on its inner circumferential surface. The terminal 13 of the electronic component 10N is physically and electrically connected to the terminal 13 of the electronic component 10N by passing the fastening member 72 through the mounting hole and screwing the fastening member into the mounting hole of the connection part 20N.

[0044] (Second part) The second portion 22 of the connecting part 20N is a portion that is connected to the bus bar 42 (see FIG. 5). The second portion 22 protrudes horizontally (e.g., in the X direction) from the end of the first portion 21 on the −Z direction side. The second portion 22 is a plate portion that extends horizontally. The second portion 22 is adjacent to (overlaps with) the bus bar 42 in the Z direction and is connected to the bus bar 42 from the Z direction. The second portion 22 is physically and electrically connected to the bus bar 42 by passing a fastening member 43 (e.g., a screw or bolt, see FIG. 5) that protrudes from the bus bar 42 in the +Z direction through the second portion 22 and screwing and tightening an engaging member 44 (e.g., a nut, see FIG. 3) into the fastening member 43.

[0045] (3rd part) The third portion 23 is an upright wall (side wall) that stands in the +Z direction from both horizontal end portions of the second portion 22. The third portion 23 is a wall that extends along the Z direction. The third portion 23 is connected to the first portion 21 and also to the second portion 22. The third portion 23 extends at an incline that increases in the X direction as it progresses in the -Z direction, for example. The third portion 23 may be provided in the connection part 20M described above. On the other hand, the connection part 20N may not have the third portion 23.

[0046] <3.2 External connection parts> Next, the connecting part 30 for external connection will be described. The connection part 30 is a part that electrically connects the external connection bus bar 76 and the wiring board 40. In this embodiment, the connection part 30 electrically connects the external connection bus bar 76 and the bus bar 42 (see FIG. 5 ) included in the wiring board 40. The external connection bus bar 76 is electrically connected to an external device. In this disclosure, the term "external device" refers to an electrical device that exists outside the electrical connection unit 1. Examples of the external device include, but are not limited to, a battery unit mounted on a vehicle or an inverter for driving a vehicle motor. The connection part 30 has a configuration that includes, for example, a first part, a second part, and a third part similar to the connection part 20M, and detailed description thereof will be omitted.

[0047] An external connection bus bar 76 is physically and electrically connected to the upper end of the connection component 30 (the upper end of the first portion) by a fastening member 73 (for example, a screw or a bolt). The lower part (second part) of the connecting part 30 is physically and electrically connected to the bus bar 42 by passing a fastening member 43 (e.g., a screw or bolt, see Figure 5) protruding from the bus bar 42 in the +Z direction through the connecting part 30 and screwing and tightening an engaging member 44 (e.g., a nut, see Figure 3) onto the fastening member 43.

[0048] <3.3 Wiring board> Next, the wiring board 40 will be described. FIG. 5 is a perspective view of a wiring board 40. The wiring board 40 is a component that forms at least a portion of the electrical paths between multiple electronic components 10 and / or at least a portion of the electrical paths between the electronic components 10 and an external device. In this disclosure, the term "wiring board" refers to a board-type wiring structure. "Board-type" refers to a plate-like structure that is flat when viewed overall, regardless of its detailed shape. In this disclosure, "plate-like," "sheet-like," or "flat" does not necessarily mean a completely flat structure, but may also include a surface that partially contains a fixing structure or rib that protrudes in the Z direction, or a surface that has an uneven shape that conforms to the thickness of the bus bar. In this embodiment, the wiring board 40 is a plate-like structure that is flat in the X and Y directions.

[0049] The wiring board 40 includes, for example, a base plate 41, one or more (e.g., a plurality of) bus bars 42, and a plurality of fastening members 43. In this embodiment, the base plate 41 and the plurality of bus bars 42 are integrated by insert molding. For example, the wiring board 40 is formed as a single member by insert molding the bus bars 42 with the base plate 41 after the fastening members 43 are fixed to the bus bars 42. In other words, the bus bars 42 are integrated with the base plate 41 without using fastening members such as screws or bolts. Note that the wiring board 40 may be formed using a different structure instead of insert molding. For example, the wiring board 40 may be molded separately from the bus bars 42, and an opening (corresponding to a receiving portion 55 described later) into which the bus bars 42 can be fixed by fitting or the like may be formed in the wiring board 40, and the bus bars 42 may be fixed in the opening to form a bus bar insert plate.

[0050] 6 is a perspective view showing a partly exploded wiring board 40. For convenience of explanation, the base plate 41, the bus bar 42, and the fastening member 43 will be described below with reference to the partly exploded view of the wiring board 40.

[0051] (base plate) The base plate 41 is a holding member that holds together a plurality of bus bars 42 that are arranged horizontally at intervals from one another. The base plate 41 is made of, for example, synthetic resin and has insulating properties. The base plate 41 electrically insulates the plurality of bus bars 42 from one another. The base plate 41 is an example of a "base member" and an example of a "mounting member." The base plate 41 may also be referred to as an "insulating substrate." The base plate 41 has, for example, a flat portion 51 and a plurality of fixing portions 52. The fixing portions 52 will be described later.

[0052] The flat surface portion 51 is a plate-shaped portion of the base plate 41. The flat surface portion 51 is a plate-shaped portion extending in the horizontal direction. The flat surface portion 51 forms the main portion of the base plate 41. The flat surface portion 51 forms the base portion (insulating base portion) of the base plate 41. In this embodiment, the flat surface portion 51 extends across the entire width of the base plate 41 in the X direction and across the entire width of the base plate 41 in the Y direction, excluding the four corner portions of the base plate 41.

[0053] The flat portion 51 has a first surface 51a and a second surface 51b. The first surface 51a is a surface facing the +Z direction. The first surface 51a is a flat surface extending along the horizontal direction. The first surface 51a faces the multiple electronic components 10 and also faces the insulating cover 93 (see FIG. 1) of the electrical connection unit 1. The second surface 51b is located on the opposite side to the first surface 51a. The second surface 51b is a surface facing the -Z direction. The second surface 51b is a flat surface extending along the horizontal direction. The second surface 51b faces the metal plate 80 (see FIG. 1). The thickness direction of the flat portion 51 (the plate thickness direction, the normal direction of the first surface 51a and the second surface 51b) is the Z direction.

[0054] The flat portion 51 has, for example, one or more (e.g., multiple) accommodating portions 55 that each accommodate a bus bar 42. The multiple accommodating portions 55 are formed spaced apart from one another in the X direction or the Y direction. Each accommodating portion 55 is, for example, a through-hole that penetrates the flat portion 51 in the Z direction. Note that, instead of a through-hole, the accommodating portion 55 may be a recess that is provided on the first surface 51a or the second surface 51b of the flat portion 51 and recessed in the Z direction. Note that in the present disclosure, the phrase "an accommodating portion penetrates the flat portion in the first direction (Z direction)" may also include a case where only a portion of the entire length of the accommodating portion 55 penetrates the flat portion 51 in the Z direction (for example, the remaining portion of the accommodating portion 55 may be a recess that is recessed in the Z direction, or may be provided inside the base plate 41 and not exposed to the outside of the base plate 41). Similarly, in the present disclosure, "the storage section is recessed in the first direction (Z direction)" may also include the case where only a portion of the overall length of the storage section 55 is recessed in the Z direction (for example, the remaining portion of the storage section 55 may be a through hole that penetrates the planar section 51 in the Z direction, or may be provided inside the base plate 41 and not exposed to the outside of the base plate 41).

[0055] When viewed from the Z direction, each accommodating portion 55 has an outer shape corresponding to the shape of the bus bar 42 to be accommodated. In this embodiment, the planar portion 51 includes the plurality of accommodating portions 55, for example, five accommodating portions 55A, 55B, 55C, 55D, and 55E. The accommodating portion 55A is provided corresponding to a bus bar 42A (described later) and accommodates the bus bar 42A. The accommodating portion 55B is provided corresponding to a bus bar 42B (described later) and accommodates the bus bar 42B. The accommodating portion 55C is provided corresponding to a bus bar 42C (described later) and accommodates the bus bar 42C. The accommodating portion 55D is provided corresponding to a bus bar 42D (described later) and accommodates the bus bar 42D. The accommodating portion 55E is provided corresponding to a bus bar 42E (described later) and accommodates the bus bar 42E.

[0056] (busbar) The busbars 42 are routing members (electrical connection members) included in the routing board 40. The busbars 42 are, for example, routing members for electrically connecting multiple electronic components 10. Alternatively, the busbars 42 may be routing members for connecting the electronic components 10 to an external device. The busbars 42 are made of metal (for example, copper or a copper alloy) and are electrically conductive. In this embodiment, the routing board 40 has, as the multiple busbars 42, for example, five busbars 42A, 42B, 42C, 42D, and 42E. The five busbars 42A, 42B, 42C, 42D, and 42E are arranged horizontally at intervals from one another. The five busbars 42A, 42B, 42C, 42D, and 42E include portions that are arranged on the same plane. The five bus bars 42A, 42B, 42C, 42D, and 42E are held by a flat portion 51 of the base plate 41.

[0057] At least a portion of each busbar 42 is a plate-like member extending in the horizontal direction. At least a portion of each busbar 42 is housed in the housing portion 55 and extends along the flat portion 51. That is, at least a portion of each busbar 42 extends along the first surface 51a of the flat portion 51. At least a portion of each busbar 42 extends horizontally within the housing portion 55. In this embodiment, each busbar 42 is a plate-like member extending in the horizontal direction over the entire length of the busbar 42. Each busbar 42 is housed in the housing portion 55 over the entire length of the busbar 42 and extends along the flat portion 51. The upper and lower surfaces of each busbar 42 can be flush with the upper and lower surfaces (first surface 51a and second surface 51b) of the flat portion 51. The upper surface of each busbar 42 and the upper surface (first surface 51a) of the flat portion 51 form the component mounting surface of the wiring board 40. Hereinafter, the portion of each bus bar 42 that is housed in housing portion 55 and extends along flat portion 51 may be referred to as a "plate portion 42p." Bus bar 42 is a member that forms a horizontal current path. Bus bar 42 may also be referred to as a "horizontal wiring member."

[0058] 7 is a plan view showing the wiring board 40. The plate portion 42p of each bus bar 42 has a first connection portion 61, a second connection portion 62, and an extension portion 63, for example.

[0059] The first connection portion 61 is a portion that comes into contact with one connection component 20 (hereinafter referred to as the "first connection component 20"). The first connection component 20 is a connection component that connects one electronic component 10 (hereinafter referred to as the "first electronic component 10") to the bus bar 42. The first connection portion 61 is a portion of the bus bar 42 that overlaps with the first connection component 20 when viewed from the Z direction. The first connection portion 61 is adjacent to the first connection component 20 in the Z direction and is connected to the first connection component 20 from the Z direction.

[0060] The second connection portion 62 is a portion that comes into contact with another connection component 20 (hereinafter referred to as the "second connection component 20"). The second connection component 20 is a connection component that connects another electronic component 10 (hereinafter referred to as the "second electronic component 10") included in the plurality of electronic components 10 to the bus bar 42. The second connection portion 62 is a portion of the bus bar 42 that overlaps with the second connection component 20 when viewed from the Z direction. The second connection portion 62 is adjacent to the second connection component 20 in the Z direction and is connected to the second connection component 20 from the Z direction.

[0061] Alternatively, the second connection portion 62 may be a portion that comes into contact with another connection component 30 (hereinafter referred to as the "second connection component 30") instead of the above example. The connection component 30 is a connection component for connecting an external device to the bus bar 42. In this case, the second connection portion 62 is a portion of the bus bar 42 that overlaps with the second connection component 30 when viewed from the Z direction. The second connection portion 62 is adjacent to the second connection component 30 in the Z direction and is connected to the second connection component 30 from the Z direction.

[0062] Furthermore, the second connection portion 62 may be a portion that comes into contact with the coupling bus bar 75 for connecting to another subunit SU, instead of the connection parts 20 and 30. In this case, the second connection portion 62 is a portion of the bus bar 42 that overlaps with the coupling bus bar 75 when viewed from the Z direction. The second connection portion 62 is adjacent to the coupling bus bar 75 in the Z direction, and is connected to the coupling bus bar 75 from the Z direction.

[0063] The extending portion 63 extends in the X direction or the Y direction from the first connecting portion 61. The extending portion 63 is provided between the first connecting portion 61 and the second connecting portion 62. The extending portion 63 extends across the first connecting portion 61 and the second connecting portion 62. The extending portion 63 connects the first connecting portion 61 and the second connecting portion 62.

[0064] In this embodiment, the first connection portion 61, the second connection portion 62, and the extension portion 63 are plate-shaped and extend in the horizontal direction. In this embodiment, each bus bar 42 is housed in the housing portion 55 across at least the first connection portion 61 and the second connection portion 62, and extends along the flat portion 51. For example, the first connection portion 61, the second connection portion 62, and the extension portion 63 are housed in the housing portion 55 and extend along the flat portion 51.

[0065] In this embodiment, the extension portions 63 of some of the bus bars 42 are accommodated in the accommodation portion 55, and thereby extend through the region R that overlaps with the electronic component 10 when viewed from the Z direction, so as to span both sides of the region R. For example, the extension portions 63 have a portion that extends linearly along the X direction. This portion extends through the region R that overlaps with the electronic component 10 when viewed from the Z direction, so as to span both the +X direction side and the −X direction side of the region R. In other words, by accommodating the bus bars 42 in the accommodation portion 55, they can be more easily routed along a better route (for example, a route with a shorter distance) without being obstructed by the presence of the electronic component 10.

[0066] Furthermore, one or more bus bars 42 may have an extension portion 64 in addition to the first connection portion 61, the second connection portion 62, and the extension portion 63. The extension portion 64 is an extended or branched portion of the bus bar 42 for the purpose of increasing the heat dissipation area and / or the heat capacity for heat storage (heat absorption). The extension portion 64 is a portion not used for electrical connection. For example, the extension portion 64 is located on the opposite side of the extension portion 63 from the first connection portion 61 (or the second connection portion 62). The extension portion 64 has a plate shape extending in the horizontal direction. The extension portion 64 is housed in the housing portion 55 and extends along the flat portion 51. The extension portion 64 extends to a region R that overlaps with the electronic component 10 when viewed from the Z direction, and has an end 42e1 of the bus bar 42 at a position that overlaps with the electronic component 10 when viewed from the Z direction.

[0067] <4. Metal plates, insulating sheets, heat transfer members, and insulating covers> Next, the metal plate 80, the insulating sheet 91, the heat transfer member 92, and the insulating cover 93 will be described.

[0068] <4.1 Metal Plate> 8 is a partially exploded perspective view of the electrical connection unit 1. The metal plate 80 is a member that ensures the rigidity of the electrical connection unit 1 and enhances the heat dissipation of the electrical connection unit 1. The metal plate 80 is made of metal (for example, aluminum or an aluminum alloy). The metal plate 80 may also be referred to as a "rigid member." The metal plate 80 is a single piece of metal plate.

[0069] When viewed from the Z direction, the metal plate 80 has a rectangular shape aligned with the X direction. The metal plate 80 has a first end 80e1, a second end 80e2, a third end 80e3, and a fourth end 80e4. The first end 80e1 and the second end 80e2 are a pair of ends in the longitudinal direction of the metal plate 80 and are spaced apart in the X direction. The third end 80e3 and the fourth end 80e4 are a pair of ends in the lateral direction of the metal plate 80 and are spaced apart in the Y direction. The metal plate 80 includes, for example, a flat portion 81, a plurality of fixing portions 82, and a plurality of fixing portions 83.

[0070] The flat surface portion 81 is a portion of the metal plate 80 that is formed into a plate shape. The flat surface portion 81 is a plate-like portion that extends horizontally. The flat surface portion 81 forms the main portion of the metal plate 80. The flat surface portion 81 forms the base (metal base) of the metal plate 80. In this embodiment, the flat surface portion 81 is large enough to cover the three subunits SU from below. The flat surface portion 81 faces the wiring board 40 of the three subunits SU. In this embodiment, the metal plate 80 faces the second surface 51b of the flat surface portion 51 of each subunit SU, with a gap S1 (see FIG. 10) between it and the second surface 51b of the flat surface portion 51 of each subunit SU.

[0071] The fixing portions 82 are fixing portions for fixing the base plate 41 of each subunit SU to the metal plate 80. When viewed from the Z direction, the fixing portions 82 are provided at positions corresponding to the fixing portions 52 of the base plate 41 of each subunit SU. The fixing portions 82 are cylindrical or prismatic bosses that protrude in the +Z direction from the flat portion 81 of the metal plate 80. The fixing portions 82 will be described in detail later.

[0072] The fixing portions 83 are fixing portions for fixing the electronic components 10 of each subunit SU directly to the metal plate 80 without using the base plate 41. When viewed from the Z direction, the fixing portions 83 are provided at positions corresponding to the mounting portions 14 of the electronic components 10 of each subunit SU. The fixing portions 83 are cylindrical or prismatic bosses that protrude in the +Z direction from the flat portion 81. The fixing portions 83 will be described in detail later.

[0073] <4.2 Insulation sheet> The insulating sheet 91 is an insulating member for electrically insulating the metal plate 80 from the bus bars 42 of each subunit SU. The insulating sheet 91 is made of a synthetic resin such as polyester or polyimide, and has insulating properties. The insulating sheet 91 has a rectangular shape when viewed from the Z direction. The insulating sheet 91 has a sheet shape that extends horizontally. The insulating sheet 91 is disposed between the flat surface 81 of the metal plate 80 and the wiring board 40 of each subunit SU. For example, the insulating sheet 91 is disposed between the flat surface 81 of the metal plate 80 and a plurality of heat transfer members 92.

[0074] In this embodiment, the insulating sheet 91 is attached to the flat portion 81 of the metal plate 80. The insulating sheet 91 has cutouts or openings to avoid the fixing portions 82 and 83 of the metal plate 80. Note that, instead of the above example, the insulating sheet 91 may be provided between the wiring board 40 of each subunit SU and the plurality of heat transfer members 92. Note that if the heat transfer members 92 have insulating properties and the necessary insulation is ensured by the heat transfer members 92, the insulating sheet 91 may be omitted.

[0075] 4.3 Heat transfer materials The heat transfer member 92 is a member for transferring heat generated by the electronic component 10 when current is applied and / or heat (Joule heat) generated by the bus bar 42 itself when current is applied to the metal plate 80. The heat transfer member 92 is, for example, an elastic heat transfer sheet (for example, a thermally conductive silicone sheet). However, the heat transfer member 92 is not limited to the above example, and may be a heat transfer member formed of a thermally conductive gel or other materials.

[0076] 9 is a bottom view showing the wiring board 40. In this embodiment, the plurality of heat transfer members 92 are provided partially on the wiring board 40. For example, the plurality of heat transfer members 92 are arranged at positions overlapping with portions of the bus bars 42 when viewed from the Z direction. Furthermore, the plurality of heat transfer members 92 are arranged at positions overlapping with portions of the bus bars 42 near the electronic components 10 (e.g., electronic components 10A and 10B) when viewed from the Z direction. In this embodiment, the plurality of heat transfer members 92 are arranged at positions overlapping with the connection components 20 when viewed from the Z direction.

[0077] 7. In this embodiment, the heat transfer member 92 is disposed between the metal plate 80 and the bus bar 42. The heat transfer member 92 transfers heat transferred from the electronic component 10 to the bus bar 42 and / or heat generated in the bus bar 42 from the bus bar 42 to the metal plate 80.

[0078] In this embodiment, a portion of the heat transfer member 92 contacts the bus bar 42 at a position that overlaps the connection component 20 when viewed from the Z direction. In this case, the heat transfer member 92 makes it easier to transfer heat that is transferred from the terminal 13 of the electronic component 10 to the connection component 20 from the connection component 20 to the metal plate 80 via the bus bar 42.

[0079] In this embodiment, a portion of the heat transfer member 92 is disposed at a position overlapping with the head 43b of the fastening member 43 when viewed from the Z direction, and is in contact with the head 43b of the fastening member 43. In this case, the heat transfer member 92 facilitates the transfer of heat, which is transferred from the terminal 13 of the electronic component 10 to the connecting part 20, from the fastening member 43 to the metal plate 80.

[0080] In this embodiment, a portion of the heat transfer member 92 contacts the bus bar 42 at a position that overlaps the electronic component 10 when viewed from the Z direction. In this case, the heat transfer member 92 makes it easier to transfer heat, which is transferred from the electronic component 10 to the bus bar 42, from the bus bar 42 to the metal plate 80. In the example shown in FIG. 10 , the upper surface of the bus bar 42 contacts the electronic component 10, so that the bus bar 42 is thermally connected to the electronic component 10. Note that the portion of the bus bar 42 that is thermally connected to the electronic component 10 may be the extension portion 63 or the extension portion 64.

[0081] <4.4 Insulation cover> Returning to FIG. 1, the insulating cover 93 will be described. The insulating cover 93 is a member for preventing fingers from touching the electrical paths of the main body unit MU. The insulating cover 93 is made of, for example, synthetic resin and has insulating properties. The insulating cover 93 is, for example, box-shaped with an open side in the -Z direction. The insulating cover 93 has multiple air vents 93h. The insulating cover 93 is attached to the metal plate 80 along the Z direction. Note that the insulating cover 93 is not limited to a box-shaped member, and may be a sheet-shaped member that covers the electrical paths of the main body unit MU.

[0082] <7. Fixed structure> Next, the anchoring structure of the subunit SU will be described.

[0083] <7.1 Structure of Metal Plate> Fig. 11 is a cross-sectional view taken along line BB of the structure shown in Fig. 7. The metal plate 80 has the fixing portion 82 and the fixing portion 83 as described above.

[0084] The fixing portion 82 is a boss that protrudes in the +Z direction from the flat portion 81 of the metal plate 80. The fixing portion 82 protrudes, for example, further in the +Z direction than the first surface 51a of the flat portion 51 of the base plate 41. In this embodiment, the fixing portion 82 protrudes more in the +Z direction than a fixing portion 83, which will be described later. The fixing portion 82 faces the fixing portion 52 of the base plate 41 in the Z direction. The fixing portion 82 has an engagement hole 82h that opens in the +Z direction. The inner circumferential surface of the engagement hole 82h has a thread groove.

[0085] The fixing portion 83 is a boss that protrudes from the flat portion 81 in the +Z direction. The fixing portion 83 is inserted into a through hole 51h (described later) in the flat portion 51 of the base plate 41. For example, the fixing portion 83 protrudes through the through hole 51h in the flat portion 51 to a position that is the same as the first surface 51a of the flat portion 51 or to a position that exceeds the first surface 51a of the flat portion 51 (a position on the +Z direction side of the first surface 51a). The fixing portion 83 faces the mounting portion 14 of the electronic component 10 in the Z direction. The fixing portion 83 has an engagement hole 83h that opens in the +Z direction. The inner circumferential surface of the engagement hole 83h has a thread groove.

[0086] A fastening member 112 (e.g., a screw or a bolt) is passed through the mounting portion 14 of the electronic component 10 from the +Z direction side. When the fastening member 112 passed through the mounting portion 14 of the electronic component 10 engages with the engaging hole 83h of the fixing portion 83 of the metal plate 80, the electronic component 10 is fixed to the metal plate 80 without the base plate 41 being interposed therebetween.

[0087] <7.2 Structure of wiring board> The base plate 41 has a fixing portion 52 that is fixed to the fixing portion 82 of the metal plate 80. The fixing portion 52 has, for example, an upright plate portion 52a and a horizontal plate portion (upper plate portion) 52b.

[0088] The upright plate portion 52a stands in the +Z direction from the end of the flat portion 51 of the base plate 41. The upright plate portion 52a is a plate portion extending along the Y and Z directions. The thickness direction of the upright plate portion 52a is the X direction.

[0089] The horizontal plate portion 52b extends horizontally from the +Z-direction end of the upright plate portion 52a. The horizontal plate portion 52b is a plate portion that extends horizontally. The horizontal plate portion 52b faces the fixing portion 82 of the metal plate 80 in the Z direction. The horizontal plate portion 52b has insertion holes 52h that face the engagement holes 82h of the fixing portion 82 of the metal plate 80. A fastening member 111 (e.g., a screw or bolt) is passed through the insertion holes 52h. When the fastening member 111 passed through the insertion holes 52h of the fixing portion 52 of the base plate 41 engages with the engagement holes 82h of the fixing portion 82 of the metal plate 80, the base plate 41 is fixed to the metal plate 80. The horizontal plate portions 52b of the fixing portions 52 of a pair of adjacent subunits SU on the metal plate 80 overlap the upper surfaces of the bosses of the metal plate 80 and are fastened together by the fastening members 111. The fixing structure including the fixing portions 52 and 82 is used in common to fix a pair of adjacent subunits SU on the metal plate 80.

[0090] Furthermore, the flat surface portion 51 of the base plate 41 has the above-described through hole 51h. The through hole 51h penetrates the flat surface portion 51 in the Z direction. When viewed from the Z direction, the through hole 51h is provided at a position corresponding to the fixing portion 83 of the metal plate 80. The fixing portion 83 of the metal plate 80 passes through the through hole 51h of the base plate 41 and protrudes to the same position as the first surface 51a of the flat surface portion 51 or further in the +Z direction than the first surface 51a of the flat surface portion 51. The mounting portion 14 of the electronic component 10 is fixed to the fixing portion 83 at the same position as the first surface 51a of the flat surface portion 51 or further in the +Z direction than the first surface 51a of the flat surface portion 51.

[0091] <8. Heat dissipation paths related to the fixed structure> Next, the heat dissipation path associated with the fixing portion 83 of the metal plate 80 will be described. 12 is a cross-sectional view illustrating a heat dissipation path associated with the fixing portion 83 of the metal plate 80. In this embodiment, the fixing portion 83 of the metal plate 80 is not in contact with a high-temperature portion (e.g., the terminal 13) of the electronic component 10. In this embodiment, a gap S2 through which air can pass is provided between the fixing portion 83 and the inner circumferential surface 51ha of the through hole 51h of the base plate 41. The through hole 51h may be opened wide so that a portion of the through hole 51h does not overlap with the mounting portion 14 of the electronic component 10 when viewed from the Z direction, for example.

[0092] In this embodiment, the temperature of the fixing portion 83 of the metal plate 80 tends to be lower than the temperature of the bus bar 42. In this case, convection occurs due to the temperature difference between the fixing portion 83 of the metal plate 80 (low temperature) and the bus bar 42 (high temperature).

[0093] Specifically, in response to the generation of an upward flow of warm air (see arrow A1) around the bus bar 42, a downward flow (see arrow A2) is generated around the fixing portion 83 of the metal plate 80 through the through hole 51h of the base plate 41 toward the bottom of the base plate 41. When this downward flow is generated, an upward flow (see arrow A3) is generated near the inner circumferential surface 51ha of the through hole 51h, which moves the air (warm air) in the gap S1 between the metal plate 80 and the base plate 41 toward the top of the base plate 41, as if pushed by the air moving in the downward flow. This prevents warm air from being trapped in the gap S1 between the metal plate 80 and the base plate 41, and promotes heat dissipation from the electrical connection unit 1.

[0094] (Variation) FIG. 13 is a cross-sectional view illustrating a modified example of the heat dissipation path. In this modified example, the metal plate 80 has a protrusion 84 instead of / in addition to the fixing portion 83. The protrusion 84 is a protrusion for heat dissipation. The protrusion 84 does not have to be used for the fixing structure. The protrusion 84 is a cylindrical or prismatic boss protruding in the +Z direction from the flat portion 81 of the metal plate 80. The protrusion 84 is inserted into the through-hole 51h of the flat portion 51 of the base plate 41. For example, the protrusion 84 passes through the through-hole 51h of the flat portion 51 and protrudes to a position flush with the first surface 51a of the flat portion 51 or to a position beyond the first surface 51a of the flat portion 51 (a position on the +Z direction side of the first surface 51a).

[0095] According to the configuration of this modified example, the temperature of the protruding portion 84 of the metal plate 80 tends to be lower than the temperature of the bus bar 42. In this case, convection occurs due to the temperature difference between the protruding portion 84 of the metal plate 80 (low temperature) and the bus bar 42 (high temperature). This causes air flows in the directions of the arrows A1 to A3 described above, and promotes heat dissipation from the electrical connection unit 1.

[0096] <9. Thermal expansion / contraction absorption structure related to the fixing structure> Next, the structure for absorbing thermal expansion / contraction related to the fixing structure will be described. FIG. 14 is a cross-sectional view illustrating a structure for absorbing thermal expansion / contraction associated with the fixing portion 82. In this embodiment, the wiring board 40 of the subunit SUX includes a base plate 41 and a bus bar 42. The flat portion 51 of the base plate 41 includes a housing portion 55 for housing the bus bar 42. The fixing portion 52 of the base plate 41 includes an upright plate portion 52a that stands in the Z direction from the flat portion 51 and a horizontal plate portion 52b that extends horizontally from the end of the upright plate portion 52a in the +Z direction. The horizontal plate portion 52b is disposed at a position different from the first surface 51a in the Z direction. The horizontal plate portion 52b includes an insertion hole 52h through which a fastening member 111 is passed. The horizontal plate portion 52b is fixed to the fixing portion 82 of the metal plate 80 by the fastening member 111.

[0097] The metal plate 80 has a fixing portion 83 that protrudes from the flat portion 81 of the metal plate 80 and is inserted into the through-hole 51h of the base plate 41 to fix the electronic component 10. The length L1 in the Z direction of the standing plate portion 52a is greater than the length L2 in the Z direction of the fixing portion 83.

[0098] In this embodiment, the wiring board 40 of the subunit SUY has a base plate 41 and a bus bar 42. The flat portion 51 of the base plate 41 has an accommodation portion 55 that accommodates the bus bar 42. The fixing portion 52 of the base plate 41 has an upright plate portion 52a that stands in the Z direction from the flat portion 51 and a horizontal plate portion 52b that extends horizontally from the +Z direction end of the upright plate portion 52a. The horizontal plate portion 52b is disposed at a position different from the first surface 51a in the Z direction. The horizontal plate portion 52b of the base plate 41 of the subunit SUY overlaps with the horizontal plate portion 52b of the base plate 41 of the subunit SUX. The horizontal plate portion 52b of the base plate 41 of the subunit SUY has an insertion hole 52h through which the fastening member 111 is passed. The horizontal plate portion 52b of the base plate 41 of the subunit SUY is fastened together with the base plate 41 and horizontal plate portion 52b of the subunit SUX to the fixing portion 82 of the metal plate 80 by fastening members 111.

[0099] 15 is a cross-sectional view showing the function of the absorption structure. Here, the linear expansion coefficient of base plate 41, which is made of synthetic resin, is greater than that of metal plate 80, which is made of metal. Therefore, during thermal expansion, base plate 41 tends to expand more than metal plate 80. On the other hand, during thermal contraction, base plate 41 tends to contract more than metal plate 80.

[0100] In this embodiment, the fixing portion 52 of the base plate 41 has an upright plate portion 52a. With such upright plate portion 52a, during thermal expansion, the upright plate portion 52a bends in the X direction, thereby preventing a large load from being applied to the flat portion 51 and / or the fixing portion 52 of the base plate 41. Similarly, during thermal contraction, the upright plate portion 52a bends in the X direction, thereby preventing a large load from being applied to the flat portion 51 and / or the fixing portion 52 of the base plate 41.

[0101] 10. Fixed structures associated with multiple subunits Next, a fixing structure related to the plurality of subunits SU will be described with reference back to Fig. 8. In this embodiment, the main body MU is divided into a plurality of subunits SU (for example, three subunits SUX, SUY, and SUZ).

[0102] The subunit SUX includes a plurality of electronic components 10X, a base plate 41, and a plurality of bus bars 42. The plurality of bus bars 42 includes portions that are arranged on the same plane as one another, and are electrically connected to the plurality of electronic components 10X.

[0103] The subunit SUY includes a plurality of electronic components 10Y, a base plate 41, and a plurality of bus bars 42. The plurality of bus bars 42 includes portions that are arranged on the same plane as one another and are electrically connected to the plurality of electronic components 10Y. The subunit SUY is electrically connected to the subunit SUX via, for example, a connecting bus bar 75.

[0104] The subunit SUZ includes a plurality of electronic components 10Z, a base plate 41, and a plurality of bus bars 42. The plurality of bus bars 42 includes portions that are arranged on the same plane as one another and are electrically connected to the plurality of electronic components 10Z. The subunit SUZ is electrically connected to the subunit SUY via, for example, a plurality of connecting bus bars 75.

[0105] In this embodiment, the plurality of subunits SU (for example, three subunits SUX, SUY, and SUZ) are each fixed to a metal plate 80. As a result, the plurality of subunits SU (for example, three subunits SUX, SUY, and SUZ) are held together by the single metal plate 80.

[0106] In this embodiment, the longitudinal direction of the subunit SUX is the X direction. The longitudinal direction of the subunit SUY is the X direction. The longitudinal direction of the subunit SUZ is the X direction. Multiple subunits SU (e.g., three subunits SUX, SUY, and SUZ) are adjacent to each other in the X direction and are aligned in a row in the X direction. The longitudinal direction of the metal plate 80 is the X direction. The length of the metal plate 80 in the X direction is greater than the total length of the multiple subunits SU (e.g., three subunits SUX, SUY, and SUZ) in the X direction.

[0107] In this embodiment, the fixing portion 52 of the subunit SUX and the fixing portion 52 of the subunit SUY are arranged in positions that overlap in the Z direction. The fixing portion 52 of the subunit SUX and the fixing portion 52 of the subunit SUY are fixed together to the fixing portion 82 of the metal plate 80 by one fastening member 111.

[0108] Similarly, the fixing portion 52 of the subunit SUY and the fixing portion 52 of the subunit SUZ are arranged in positions where they overlap in the Z direction. The fixing portion 52 of the subunit SUY and the fixing portion 52 of the subunit SUZ are fixed together to the fixing portion 82 of the metal plate 80 by one fastening member 111.

[0109] In this embodiment, the heat generated by the electronic component 10X and the bus bar 42 included in the sub-unit SUX is transmitted to the metal plate 80 through one or more heat transfer members 92 facing the sub-unit SUX. Similarly, the heat generated by the electronic component 10Y and the bus bar 42 included in the sub-unit SUY is transmitted to the metal plate 80 through one or more heat transfer members 92 facing the sub-unit SUY. The heat generated by the electronic component 10Z and the bus bar 42 included in the sub-unit SUZ is transmitted to the metal plate 80 through one or more heat transfer members 92 facing the sub-unit SUZ.

[0110] In this embodiment, the plurality of sub-units SU (for example, three sub-units SUX, SUY, and SUZ) may have different heat generation amounts from each other. Even when the heat generation amounts of the plurality of sub-units SU are different, the cooling of the plurality of sub-units SU (for example, three sub-units SUX, SUY, and SUZ) can be promoted by one large metal plate 80. For example, when the heat generation amounts of the plurality of sub-units SU are different, the temperature equalization of the plurality of sub-units SU can be achieved by one large metal plate 80.

[0111] <14. Advantages of this embodiment> <A. Advantages related to the wiring board> As a comparative example, consider an electrical connection unit in which a bus bar is arranged in a standing posture with respect to the lower wall of the housing. In such a configuration of the comparative example, it may be difficult to reduce the height of the electrical connection unit due to the width of the standing bus bar.

[0112] On the other hand, in this embodiment, the electrical connection unit 1 has a first electronic component 10 and a wiring board 40. The wiring board 40 includes a base plate 41 and a first bus bar 42. The base plate 41 has a plate-shaped flat portion 51 with a first surface 51a facing the first electronic component 10. The flat portion 51 has a first accommodating portion 55 that is recessed in the Z direction or that penetrates the flat portion 51 in the Z direction. At least a portion of the first bus bar 42 is accommodated in the first accommodating portion 55 and extends along the flat portion 51. With this configuration, compared to the structure of the comparative example described above in which at least a portion of the wiring path is formed on a flat surface, the bus bar is less likely to affect the height direction, making it easier to reduce the height of the electrical connection unit 1.

[0113] In this embodiment, the electrical connection unit 1 has a first connection component 20. The first connection component 20 includes a portion that stands upright relative to the first bus bar 42, and electrically connects the first electronic component 10 and the first bus bar 42. The first bus bar 42 has a first connection portion 61 that contacts the first connection component 20. The first connection portion 61 is housed in the first housing portion 55 and extends along the flat portion 51. With this configuration, a larger portion of the wiring path is formed on a flat surface, making it easier to reduce the height of the electrical connection unit 1.

[0114] In this embodiment, the electrical connection unit 1 has a second connection component 20. The second connection component 20 includes a portion that stands upright relative to the first bus bar 42, and electrically connects the first bus bar 42 to a second electronic component or an external device. The first bus bar 42 has a second connection portion 62 that contacts the second connection component 20. The first bus bar 42 is housed in the first housing portion 55 across at least the first connection portion 61 and the second connection portion 62, and extends along the flat portion 51. With this configuration, a larger portion of the wiring path is formed on a flat surface, further facilitating the reduction in height of the electrical connection unit 1.

[0115] In this embodiment, the first bus bar 42 has an extension portion 63 between the first connection portion 61 and the second connection portion 62. The extension portion 63 is accommodated in the first housing portion 55 and extends through the region R that overlaps with the electronic component 10 when viewed from the Z direction, so as to span both sides of the region R. With this configuration, since the extension portion 63 is accommodated in the first housing portion 55, the presence of the electronic component 10 is less likely to restrict the wiring layout. This enables a wiring layout that provides more advantageous electrical characteristics, such as making it easier to extend the extension portion 63 linearly. Furthermore, it is possible to avoid routing the bus bar in a way that bypasses the electronic component 10. This improves the electrical characteristics of the electrical connection unit 1 and / or reduces the size of the electrical connection unit 1.

[0116] In this embodiment, when viewed from the Z direction, the first bus bar 42 has an extension 64 that extends to the region R that overlaps with the first electronic component 10 and has an end 42e1 at a position that overlaps with the first electronic component 10. The extension 64 is housed in the first housing portion 55 and extends along the flat portion 51. With this configuration, housing the extension 64 in the first housing portion 55 reduces the height of the electrical connection unit 1, and a metallic heat dissipation portion (extension 64) that promotes heat dissipation and / or heat storage of the first electronic component 10 can be disposed below the first electronic component 10. This improves the heat dissipation and / or heat storage properties of the electrical connection unit 1.

[0117] In this embodiment, the first bus bar 42 is accommodated in the first accommodating portion 55 over the entire length of the first bus bar 42 and extends along the flat portion 51. With this configuration, a larger portion of the wiring path is formed on a flat surface, making it easier to reduce the height of the electrical connection unit 1.

[0118] In this embodiment, the electrical connection unit 1 has a second bus bar 42 electrically connected to the second terminal 13B of the first electronic component 10. The flat portion 51 has a second accommodating portion 55 that is recessed in the Z direction or that penetrates the flat portion 51 in the Z direction, at a position away from the first accommodating portion 55. At least a portion of the second bus bar 42 is accommodated in the second accommodating portion 55 and extends along the flat portion 51. With this configuration, a larger portion of the wiring path including the multiple bus bars 42 is held flat by the single base plate 41, further facilitating the reduction in height of the electrical connection unit 1.

[0119] In this embodiment, the electrical connection unit 1 has a third bus bar 42. The first bus bar 42 is a bus bar included in the positive electrode line PL. The third bus bar 42 is a bus bar included in the negative electrode line NL. The flat portion 51 has a third housing portion 55 that is recessed in the Z direction or that penetrates the flat portion 51 in the Z direction, at a position away from the first housing portion 55. At least a portion of the third bus bar 42 is housed in the third housing portion 55 and extends along the flat portion 51. With this configuration, a larger portion of the wiring paths that form the positive electrode lines PL and the negative electrode lines NL is held flat by a single base plate 41, making it easier to reduce the height of the electrical connection unit 1.

[0120] In this embodiment, the electrical connection unit 1 includes a fourth bus bar 42, a fifth bus bar 42, and a third connection component 100 that electrically connects the fourth bus bar 42 and the fifth bus bar 42. The flat portion 51 has a fourth accommodating portion 55 that is recessed in the Z direction or penetrates the flat portion 51 in the Z direction at a position away from the first accommodating portion 55. At least a part of the fourth bus bar 42 is accommodated in the fourth accommodating portion 55 and extends along the flat portion 51. The third connection component 100 includes a portion standing upright with respect to the fourth bus bar 42. The fifth bus bar 42 is supported by the third connection component 100 at a position away from the first bus bar 42 in the Z direction and extends parallel to the first surface 51a. According to such a configuration, it is easy to form a three-dimensional wiring path by the fourth bus bar 42, the third connection component 100, and the fifth bus bar 42. Thereby, an electrical connection unit 1 with excellent assemblability can be provided. Further, since the fourth bus bar 42 is disposed in the accommodating portion 55 of the base plate 41, a part of the three-dimensional wiring path is formed within the thickness of the base plate 41. This further facilitates making the electrical connection unit 1 more compact.

[0121] In this embodiment, the fifth bus bar 42 extends so as to straddle the first bus bar 42 at a position away from the first bus bar 42 in the Z direction. According to such a configuration, it is easy to form a wiring path that three-dimensionally intersects the first bus bar 42 by the third connection component 100 and the fifth bus bar 42. Thereby, an electrical connection unit 1 with excellent assemblability can be provided.

[0122] <B. Advantages Regarding Flat Bus Bars> As a comparative example, consider an electrical connection unit in which a bus bar is arranged in a posture standing upright with respect to the lower wall of the housing. In such a configuration of the comparative example, it is necessary to fix the bus bar to the housing in a standing posture, and it is difficult to improve the workability regarding the attachment of the bus bar. In this case, it may be difficult to improve the assemblability of the electrical connection unit 1.

[0123] On the other hand, in this embodiment, the electrical connection unit 1 has a base plate 41 and a bus bar 42. The base plate 41 includes a plate-shaped flat portion 51. The flat portion 51 has a first housing portion 55 that is recessed in the Z direction or that penetrates the flat portion 51 in the Z direction. At least a portion of the bus bar 42 is housed in the first housing portion 55 and extends along the flat portion 51. This configuration makes it easier to handle the base plate 41 and the bus bar 42 as a single unit, improving the workability of attaching the bus bar compared to the configuration of the comparative example. This improves the ease of assembly of the electrical connection unit 1.

[0124] In the present embodiment, the bus bar 42 is housed in the housing portion 55 over the entire length of the bus bar 42 and extends along the flat portion 51. This configuration improves the assembly of the electrical connection unit 1 and also makes it easier to reduce the height of the electrical connection unit 1.

[0125] In this embodiment, the bus bars 42 are integrated with the base plate 41 by insert molding. This configuration can eliminate or reduce the work of manually attaching the bus bars 42 to the housing, thereby further improving the ease of assembly of the electrical connection unit 1.

[0126] This embodiment includes a fastening member 43 that protrudes from the bus bar 42 in the Z direction, and connection components 20, 30 that are attached to the fastening member 43 from the Z direction. The connection components 20, 30 electrically connect the electronic component 10 or an external device to the bus bar 42. This configuration makes it easier to align the direction of the work to attach the connection target component to the bus bar 42 with the Z direction. Aligning the work direction further improves the ease of assembly of the electrical connection unit 1.

[0127] In this embodiment, the connecting component 20 is connected to the electronic component 10 from the X direction (or Y direction). According to such a configuration, for the electronic component 10 that needs to be connected from the X direction, by using the connecting component 20, the connection direction of the electronic component 10 to the bus bar 42 can be converted to the Z direction. Thereby, the assemblability of the electrical connection unit 1 can be further improved.

[0128] <Advantages regarding the exposed structure on the upper surface side of the bus bar> As a comparative example, consider an electrical connection unit in which the upper surface side of the bus bar 42 is covered with a synthetic resin. In such a configuration of the comparative example, it is difficult to improve the heat dissipation of the bus bar 42.

[0129] On the other hand, in this embodiment, the electrical connection unit 1 includes a first electronic component 10 and a wiring board 40. The wiring board 40 includes a base plate 41 and a bus bar 42. The base plate 41 has a plate-shaped flat portion 51 having a first surface 51a facing the first electronic component 10 and a second surface 51b located on the side opposite to the first surface 51a. The flat portion 51 has a housing portion 55 recessed in the Z direction or penetrating the flat portion 51 in the Z direction. At least a part of the bus bar 42 has a plate portion 42p housed in the housing portion 55 and extending along the flat portion 51. The plate portion 42p includes a first connection portion 61 overlapping the first connecting component 20 when viewed in the Z first direction, and an extension portion 63 extending from the first connection portion 61 in a direction intersecting the Z direction. At least a part of the extension portion 63 is exposed outside the base plate 41 on the first surface 51a side. According to such a configuration, at least a part of the portion of the bus bar 42 other than the connection portions 61 and 62 connected to other components is exposed to the outside and functions as an area for releasing heat. In this case, the heat dissipation of the electrical connection unit 1 can be improved.

[0130] In this embodiment, the extension 63 is exposed to the outside of the base plate 41 on the first surface 51a side in at least a part of the region R that overlaps with the first connecting part 20 when viewed from the Z direction. This configuration makes it easier for the part of the extension 63 to function as a heat dissipation part that transfers heat from the first connecting part 20. In this case, the heat dissipation performance of the electrical connection unit 1 can be improved.

[0131] In this embodiment, the first bus bar 42 has a second connection portion 62 that overlaps with the second connection components 20, 30 when viewed in the Z direction. The first bus bar 42 is housed in the housing portion 55 and extends along the flat portion 51 over at least the entire length between the first connection portion 61 and the second connection portion 62, and is exposed to the outside of the base plate 41 on the first surface 51a side. With this configuration, a wider portion functions as a heat dissipation area, thereby further improving the heat dissipation performance of the electrical connection unit 1.

[0132] In this embodiment, the entire length of bus bar 42 is accommodated in accommodation portion 55, extends along flat portion 51, and is exposed to the outside of base plate 41 on the first surface 51a side. With this configuration, a wider portion functions as a heat dissipation area, thereby further improving the heat dissipation performance of electrical connection unit 1.

[0133] At least a portion of the extension 63 is exposed to the outside of the base plate 41 on the second surface 51b side as well as the first surface 51a side. With this configuration, a wider portion functions as a heat dissipation area, thereby further improving the heat dissipation performance of the electrical connection unit 1.

[0134] In a modification of this embodiment, the electrical connection unit 1 includes a metal plate 80 facing the flat portion 51 with a gap S1 therebetween, and a heat transfer member 92 disposed between the bus bar 42 and the metal plate 80. The base plate 41 has a cover portion 51v that covers at least a part of the extension portion 63 on the second surface 51b side. With such a configuration, even when heat is likely to accumulate in the gap S1 between the base plate 41 and the metal plate 80, the provision of the cover portion 51v can suppress the tendency of heat to accumulate in the gap S1.

[0135] <Advantages regarding the exposed structure on the lower surface side of the bus bar> In order to enhance the holding property of the bus bar 42, a structure may be adopted in which portions of the bus bar 42 other than the connection surface with the electronic component 10 etc. are covered with resin. However, in a structure where portions of the bus bar 42 other than the connection surface are covered, there is a problem that the heat dissipation property of the bus bar 42 deteriorates. In this embodiment, the lower surface (the surface opposite to the component mounting surface) of the bus bar 42 is exposed, and a heat transfer sheet is set on this exposed surface. The heat transfer sheet is connected to a metal plate 80 (a rigid member, a heat dissipation member) provided below the wiring board 40. Thereby, heat can be favorably transferred from the bus bar 42 to the metal plate 80 (to the side opposite to the component mounting surface) via the heat transfer sheet.

[0136] <Advantages regarding the fixing structure of the sub-unit SU> In this embodiment, it includes a plurality of circuit components SUX, SUY, SUZ, and a support member (metal plate 80) that supports the plurality of circuit components SUX, SUY, SUZ on a support surface (the upper surface 81a of the flat portion 81). Each of the circuit components SUX, SUY, SUZ includes an electronic component 10 that constitutes a circuit, and a mounting member (wiring board 40) that is arranged along the support surface and mounts the electronic component 10 in a circuit component mounting region 51d formed on the component mounting surface (the upper surface 51c of the flat portion 51) opposite to the metal plate 80. The wiring board 40 is fixed to the metal plate 80 by a plurality of fixing portions 52, 82 arranged so as to surround the outside of the circuit component mounting region 51d when viewed from the normal direction of the support surface. According to this configuration, the wiring board 40 of each circuit component SUX, SUY, SUZ is fixed to the metal plate 80 by a plurality of fixing portions 52, 82 arranged to surround the outside of the circuit component mounting area 51d, thereby preventing distortion between the metal plate 80 and the wiring board 40 caused by heat generation from any of the circuit components from acting on the other circuit components.

[0137] That is, when the temperature of each circuit assembly SUX, SUY, SUZ becomes high or low, expansion or contraction of the resin wiring board 40 relative to the metal plate 80 occurs, which causes a difference in the length (pitch) between the multiple fixing positions between the metal member (rigid member) and the resin member (bus bar insert plate). This repeated expansion and contraction of the resin member may damage the bus bar insert plate near the fixing portion. In this embodiment, the fixing portion 52 of the busbar insert plate (wiring board 40) is provided at a different height from the main body portion (flat portion 51 forming the component mounting surface) and is fixed to the boss (fixing portion 82) of the metal plate 80. This allows the thermal expansion / contraction of the busbar insert plate to be absorbed by the deflection of the upright plate portion (standing wall portion) 52a. The upright plate portion 52a is located closer to the circuit component mounting area 51d than the boss (fixing portion 82) of the metal plate 80, making it possible to insulate the fixing portion (boss) 82 from the busbar 42 around the fixing portion.

[0138] In this embodiment, the metal plate 80 is an integral metal member, and the wiring boards 40 of the circuit assemblies SUX, SUY, and SUZ each include a separate base plate 41 made of resin. With this configuration, distortion caused by heat generation from any of the circuit components SUX, SUY, SUZ between the metallic support member (metal plate 80) and the resin base member (base plate 41) of the mounting member can be prevented from acting on other circuit components.

[0139] In this embodiment, each fixing portion 52, 82 comprises a columnar boss (fixing portion 82) protruding in the normal direction from the support surface of the metal plate 80, and a three-dimensional structure portion (fixing portion 52) protruding in the normal direction from the component mounting surface of the wiring board 40, and the three-dimensional structure portion (fixing portion 52) comprises an upright plate portion 52a rising in the normal direction from the component mounting surface of the wiring board 40, and an (upper plate portion) 52b extending from the tip of the upright plate portion 52a parallel to the component mounting surface and fixed to the tip of the boss 82. According to this configuration, the upper plate portion 52b of the resin fixing portion 52 is supported via the standing plate portion 52a, and this upper plate portion 52b is fixed to the metal boss 82, so that when the wiring board 40 thermally expands / contracts, the standing plate portion 52a bends in the direction along the surface of the component mounting surface, thereby preventing a large load from being applied to the flat portion 51 of the wiring board 40.

[0140] In this embodiment, the fixing portion 82 between a pair of adjacent circuit assemblies on the support surface is used in common to fix the pair of circuit assemblies. According to this configuration, the fixing portion 82 between a pair of adjacent circuit assemblies can be shared to fix the pair of circuit assemblies, thereby simplifying the fixing structure of multiple circuit assemblies and reducing costs.

[0141] In this embodiment, the circuit component mounting area 51d has a rectangular shape when viewed from the normal direction of the support surface, and the fixing portions 52 and 82 are disposed at each apex of the rectangular shape of the circuit component mounting area 51d. According to this configuration, by arranging the fixing portions 52 and 82 at the four corners of the circuit component mounting area 51d, which is rectangular in plan view, the circuit component mounting area 51d can be efficiently secured.

[0142] <Modification> Next, several modified examples will be described. Note that the configuration of each modified example other than that described below is the same as the configuration of the above-described embodiment.

[0143] (First Modification) The wiring board 40 is not limited to a structure in which the base plate 41 and the bus bar 42 are integrated by insert molding. For example, the base plate 41 may be molded with a housing portion 55 for housing the bus bar 42, and then the bus bar 42 may be placed in the housing portion 55. In this case, the bus bar 42 may be fixed to the housing portion 55 by fitting, or may be fixed to the housing portion 55 by adhesive or other fixing means. In these cases, potting may be applied to fill the gap between the bus bar 42 and the housing portion 55.

[0144] (Second Modification) The base member of the wiring board 40 is not limited to the base plate 41 having the plate-shaped flat portion 51. The wiring board 40 may be a base member (for example, an insulating sheet) having a sheet-shaped flat portion 51. In this case, the housing portion 55 may be formed by a portion of the flat portion 51 conforming to the outer shape of the bus bar 42. In the present disclosure, the term "sheet-shaped" or "sheet" is not limited to a member having a thickness of 1 mm or more, and may also refer to a member having a thickness of less than 1 mm (so-called film).

[0145] (Third Modification) The base plate 41 of the wiring board 40 may include multiple members (plate members or sheet members). The multiple members are arranged to sandwich the multiple bus bars 42 arranged horizontally, for example, from both sides in the Z direction. For example, the multiple members are integrated by sandwiching the multiple bus bars 42, for example, by lamination molding. The multiple members form a planar portion 51. In this case, the accommodating portion 55 may be formed hollow inside the base plate 41 (between the multiple members). The multiple members may be multiple plate members, multiple sheet members, or a combination of plate members and sheet members. The sheet member may be, for example, a flexible sheet member. The planar portion 51 formed by the multiple members has openings that expose at least the first connection portion 61 and the second connection portion 62 of the bus bars 42. In this case, for example, the accommodating portion 55 formed between the multiple members corresponds to an example of an "accommodating portion recessed in the first direction (Z direction)."

[0146] (Fourth Modification) The connection between the electronic component 10 and the bus bar 42 is not limited to the connection via the connection component 20. The electronic component 10 may be directly connected to the bus bar 42 using a fastening member (for example, a bolt or a screw), welding, or the like.

[0147] Several embodiments and modifications have been described above. However, the embodiments and modifications are not limited to the above examples. For example, multiple embodiments may be realized in combination with each other. [Explanation of symbols]

[0148] 1 Electrical Connection Unit 10. Electronic Components 40 Wiring board (mounting member) 41 Base plate (base material, resin material) 42 Busbar 51 Plane part 51c Top surface (component mounting surface, base surface) 51d Component mounting area 52 Fixed part (three-dimensional structure part) 52a Standing plate part 52b Upper plate 80 Metal plate (support member, metal member) 81 Plane part 81a Top surface (support surface) 82 Fixed part (boss) SU, SUX, SUY, SUZ Subunits (circuit components)

Claims

1. a plurality of circuit structures; a support member for supporting the plurality of circuit assemblies, Each circuit component is A plurality of electronic components; a bus bar that electrically connects the plurality of electronic components; an insulating base member that holds the bus bar, When a direction in which the plurality of electronic components and the base member face each other is defined as a first direction, each base member has a facing region facing the plurality of electronic components when viewed from the first direction, and is fixed to the support member by a plurality of fixing portions arranged so as to surround the outside of the facing region when viewed from the first direction; Electrical connection unit.

2. the plurality of circuit components include a first circuit component and a second circuit component disposed adjacent to the first circuit component; the first circuit component and the second circuit component generate heat at different times; The electrical connection unit according to claim 1 .

3. the support member is a single piece of metal plate; The base members are synthetic resin members separate from each other.

3. The electrical connection unit according to claim 1 or 2.

4. the base member has a base surface including the facing region, Each fixed part is a first fixing portion protruding from the support member in the first direction; a second fixing portion protruding from the base surface of the base member, the second fixed portion includes a first portion rising from the base surface in the first direction, and a second portion extending from a tip of the first portion in parallel with the base surface and fixed to the first fixed portion.

4. The electrical connection unit according to claim 3.

5. the plurality of circuit components include a first circuit component and a second circuit component disposed adjacent to the first circuit component; the plurality of fixing portions include a fixing portion that is disposed at a boundary between the first circuit component and the second circuit component and is used in common to fix the first circuit component and the second circuit component together; 3. The electrical connection unit according to claim 1 or 2.

6. When viewed from the first direction, the facing region has a rectangular shape, and the plurality of fixing portions are arranged corresponding to four corners of the facing region.

3. The electrical connection unit according to claim 1 or 2.

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