Electronic control device

Abstract

Provided is an electronic control device comprising a plurality of detachable sub-enclosures, the plurality of sub-enclosures each having a board on which a first electronic component is mounted, an enclosure accommodating the board, and a first fin part that cools the first electronic component. The electronic control device comprises: a main board, which is electrically connected to the plurality of sub-enclosures via board-to-board connectors, and on which a second electronic component is mounted; and a main enclosure in which the main board is accommodated. The electronic control device comprises a plate-like member which is disposed between the plurality of sub-enclosures and the main enclosure and has openings that respectively correspond to the plurality of sub-enclosures. The main enclosure and the plate-like member form a cooling channel through which a refrigerant circulates, and the first fin part is inserted through the opening to be disposed in the cooling channel.

Description

Electronic control unit

[0001] The present invention relates to an electronic control device.

[0002] The hardware associated with the ECU requires a structure with excellent heat dissipation performance to tolerate heat generated by electronic components due to an increase in processing load. As an example of a hardware structure with excellent heat dissipation performance, Patent Document 1 listed below discloses a power conversion device having a structure in which sealing members 104 are attached to two locations on the top and bottom surfaces of a power module 101 and the power module is sandwiched between an upper (lower) cover 103A (B) and a housing 100.

[0003] JP 2023-011958 A

[0004] In the configuration described in Patent Document 1, depending on the finished state, variations can occur between the height of the boss surface of the housing and the height of the power module wall, making it difficult to generate uniform surface pressure on the upper (lower) cover and creating problems with ensuring sealing.

[0005] An electronic control device comprising a plurality of detachable sub-housings, each of which has a board on which a first electronic component is mounted, a housing that houses the board, and a first fin portion that cools the first electronic component; a main board that is electrically connected to the plurality of sub-housings via board-to-board connectors and on which a second electronic component is mounted, and a main housing that houses the main board; and a plate-like member that is arranged between the plurality of sub-housings and the main housing and has openings that correspond to each of the plurality of sub-housings, the main housing and the plate-like member forming a cooling flow path through which a refrigerant flows, and the first fin portion is inserted through the opening and arranged within the cooling flow path.

[0006] It is possible to provide an electronic control device that achieves improved cooling performance, easier housing replacement, and ensures sealing performance.

[0007] FIG. 1 is a perspective view of the overall appearance of an electronic control device according to one embodiment of the present invention. FIG. 2 is an exploded perspective view of FIG. 1. FIG. 3 is an explanatory diagram of a plate-shaped member according to one embodiment of the present invention. FIG. 4 is an exploded perspective view of a sub-housing according to one embodiment of the present invention. FIG. 5 is a cross-sectional view of a sub-housing according to one embodiment of the present invention. FIG. 6 is an exploded perspective view of a main housing according to one embodiment of the present invention. FIG. 7 is a cross-sectional view of a main housing according to one embodiment of the present invention. FIG. 8 is a cross-sectional view of an electronic control device according to one embodiment of the present invention. FIG. 9 is a diagram explaining the positional relationship between electronic components according to one embodiment of the present invention. FIG. 10 is a diagram explaining the positional relationship between electronic components according to one embodiment of the present invention. FIG. 11 is a diagram explaining the positional relationship between electronic components according to one embodiment of the present invention. FIG. 12 is a diagram explaining the positional relationship between electronic components according to one embodiment of the present invention. FIG. 13 is a diagram explaining the positional relationship between electronic components according to one embodiment of the present invention. FIG. 14 is a diagram explaining the positional relationship between electronic components according to one embodiment of the present invention. FIG. 15 is a diagram explaining the positional relationship between electronic components according to one embodiment of the present invention. FIG. 16 is a diagram explaining the positional relationship between electronic components according to one embodiment of the present invention. FIG. 17 is a diagram explaining the positional relationship between electronic components according to one embodiment of the present invention. FIG. 18 is a diagram explaining the positional relationship between electronic components according to one embodiment of the present invention. FIG. 19 is a diagram explaining the positional relationship between electronic components according to one embodiment of the present invention. FIG. 20 is a diagram explaining the positional relationship between electronic components according to one embodiment of the present invention. FIG. 21 is a diagram explaining the positional relationship between electronic components according to one embodiment of the present invention. FIG.

[0008] Hereinafter, an embodiment of the present invention will be described with reference to the drawings. The following description and drawings are examples for explaining the present invention, and some omissions and simplifications have been made as appropriate for clarity of explanation. The present invention can be implemented in various other forms. Unless otherwise specified, each component may be singular or plural.

[0009] In order to facilitate understanding of the invention, the position, size, shape, range, etc. of each component shown in the drawings may not represent the actual position, size, shape, range, etc. Therefore, the present invention is not necessarily limited to the position, size, shape, range, etc. disclosed in the drawings.

[0010] (One embodiment and overall configuration) (FIGS. 1 to 5) The electronic control device 100 has a main housing 1 and multiple sub-housings 2. The sub-housings 2 are detachable from the electronic control device 100, and multiple sub-housings 2 are provided on the electronic control device 100. A plate-like member 3 is disposed between the main housing 1 and the multiple sub-housings 2. The plate-like member 3 has openings 3a corresponding to the multiple sub-housings 2 mounted on the plate-like member 3.

[0011] The plate-like member 3 has a pipe connection hole 5a, an opening 3a, a through-hole 3c, and a notch 3d. A cooling water inlet pipe 5, which allows the refrigerant flowing through a cooling flow path 7 (described below) to flow into the electronic control device 100, is attached to the pipe connection hole 5a. The opening 3a has an O-ring groove 3b. A sealing material 4 such as an O-ring is attached to the O-ring groove 3b, which seals the gap of the sub-housing 2 fitted into the opening 3a, thereby making the cooling flow path 7 watertight so that the refrigerant does not leak.

[0012] Although the O-ring groove 3b is formed in the opening 3a of the plate-like member 3, a groove for disposing an O-ring may be formed on the side of the sub-casing 2 as long as it can make the cooling flow path 7 watertight. Also, a gasket may be used as the sealing material 4 instead of an O-ring.

[0013] The plate-like member 3 has a through-hole 3c corresponding to the position of the opening 3a, through which a board-to-board connector 8 passes, connecting the sub-housing 2 to the main housing 1 (described later). The plate-like member 3 also has a notch 3d, so that when the sub-housing 2 is removed from the electronic control device 100, for example during an ECU update, the tip of a removal jig 20 can be inserted into the notch 3d, facilitating replacement of the sub-housing 2.

[0014] The sub-housing 2 includes a substrate 9b on which the first electronic component 10a is mounted, a housing that houses the substrate 9b, and a first fin portion 28a that cools the first electronic component 10a. The housing that houses the substrate 9b includes a sub-housing cover 23 and a sub-housing chassis 28. The first fin portion 28a is part of the sub-housing chassis 28. The first electronic component 10a is a SoC (System on a Chip) that mounts semiconductor elements and the like, and is thermally connected to the first fin portion 28a via a TIM 14 (Thermal Interface Material). This allows heat generated by the first electronic component 10a to be transferred to the first fin portion 28a.

[0015] Furthermore, the sub-housing 2 has, on its board 9b, an inter-board connector 8, a connector 24, a capacitor 25, and an external connector 27. The inter-board connector 8 is mounted on the surface of the board 9b on the main housing 1 side, and is electrically connected to a board of the main housing 1, which will be described later.

[0016] The board-to-board connector 8 is a connector conforming to the PCIe standard, for example, and communicates between the electronic components on the board of the sub-casing 2 and the electronic components on the board of the main housing 1 within the electronic control device 100 using a communication method such as CAN (Controller Area Network) or Ethernet.

[0017] The capacitor 25 is a passive element for reducing the impedance of the wiring that supplies power to the electronic components. The external connection connector 27 is a sensor input connector (or an Ethernet connector) for receiving sensor signals via a communication method such as LVDS (Low Voltage Differential Signal). The connector 24 is a multi-core connector for communicating with external sensors or another on-board ECU (not shown) via a communication method such as CAN or Ethernet.

[0018] The sub-housing 2 has an internal space 2d formed by assembling the sub-housing cover 23 and the sub-housing chassis 28. The internal space 2d contains the connector 24, capacitor 25, and external connector 27 mounted on the board 9b. The internal space 2d also functions as a heat dissipation path for the first electronic component 10a, contributing to air-cooling of the first electronic component 10a.

[0019] The sub-housing 2 is attached to the plate-like member 3 with bolts or the like (not shown). The first fin portion 28a has a stepped side portion 28b and cooling fins 28c. The stepped side portion 28b is formed between the sealing surface 2a that adheres to the surface of the plate-like member 3 and the surface of the first fin portion 28a on which the cooling fins 28c are formed. The stepped side portion 28b fits into the inner wall surface of the opening 3a of the plate-like member 3.

[0020] The printed circuit board 9b of the sub-housing 2 is fixed to the sub-housing chassis 28 with bolts (not shown). The first electronic component 10a is a component for arithmetic processing in the electronic control device 100. Although only one first electronic component 10a is shown mounted on the board 9b, multiple first electronic components 10a may be mounted. Furthermore, the number of components mounted on the plate-like member 3 of the sub-housing 2 is not limited to three as shown, and two or four or more components may also be mounted.

[0021] (FIGS. 6 and 7) The main housing 1 is attached with bolts (not shown) to the surface of the plate-like member 3 opposite to the surface to which the sub-housing 2 is attached. The main housing 1 is electrically connected to the multiple sub-housings 2 via inter-board connectors 8 and houses a main board 9a on which second electronic components 10b are mounted. The main board 9a has one or more second electronic components 10b, one or more external connection connectors 16, and one or more inter-board connectors 8 mounted as circuit components.

[0022] The main board 9a and the boards 9b of each sub-housing 2 are electrically connected by a plurality of inter-board connectors 8. Furthermore, the main board 9a communicates signals and supplies power to the boards 9b of the sub-housing 2. Note that the electrical connection between the main board 9a and the boards 9b of the sub-housing 2 may be via a cable. With this configuration, there is no need to provide a main power supply in the sub-housing 2, which contributes to the miniaturization of the entire device.

[0023] The main housing 1 has a main housing chassis 13 and a main housing cover 15. The main housing chassis 13 has a part of the cooling flow path 7, and has an O-ring groove 13a around the cooling flow path 7. A sealant 4 as shown in Fig. 2 is attached to the O-ring groove 13a, thereby tightly sealing the main housing 1 and the plate-like member 3 and making the cooling flow path 7 watertight.

[0024] The main housing chassis 13 has second fin portions 1c, which have the role of dissipating heat, located in the cooling flow path 7 and correspond to the positions of the second electronic components 10b. The second fin portions 1c are formed opposite the first fin portions 28a (FIG. 5) in the cooling flow path 7. The second electronic components 10b are thermally connected to the positions where the second fin portions 1c are formed via a thermal insulation material (TIM) 14, such as grease, to transfer heat. This allows heat generated by the second electronic components 10b to be exchanged with the refrigerant flowing through the cooling flow path 7.

[0025] Furthermore, the main housing chassis 13 has through holes 13b at positions corresponding to the second fin portions 1c, through which the inter-board connectors 8 pass. This facilitates electrical connection between the main board 9a of the main housing 1 and the corresponding sub-housings 2.

[0026] The main housing cover 15 has a cooling water outlet hole 15a. The cooling water outlet pipe 6 shown in Fig. 2 is attached to the outside of the cooling water outlet hole 15a. The cooling water outlet pipe 6 may be attached to the main housing chassis 13. The roles of the cooling water outlet pipe 6 and the cooling water inlet pipe 5 described above for the inflow and outflow of the refrigerant may be interchanged.

[0027] The external connector 16 is composed of a terminal such as a CAN or Ethernet for communicating control signals and sensor input signals, and a terminal for supplying power from the vehicle battery. In addition to the external connector 16, a connector 24 is also housed within the internal space 1d formed by the main housing cover 15. The internal space 1d also functions as a heat dissipation path for the second electronic component 10b, contributing to air cooling of the second electronic component 10b.

[0028] Although the cooling fins 28c of the first fin section 28a and the second fin section 1c are plate (plate-like) fins, at least one of them may be a pin (cylindrical or approximately cylindrical) fin. This allows for a larger surface area required for heat transfer even in a limited, narrow area compared to plate (plate-like) fins, improving cooling performance.

[0029] (FIG. 8) By attaching the main housing 1 to the plate-like member 3, a cooling flow path 7 through which a refrigerant flows is formed. Furthermore, by inserting the first fin portion 28a of the sub-housing 2 into the opening 3a (FIG. 3) of the plate-like member 3, the cooling fins 28c of the first fin portion 28a are disposed within the cooling flow path 7. With this configuration, the cooling flow path 7 is formed by the first fin portion 28a of the sub-housing 2, the plate-like member 3, and the second fin portion 1c of the main housing 1, and heat can be dissipated from the first electronic component 10a and the second electronic component 10b via the first fin portion 28a and the second fin portion 1c, respectively, in the same cooling flow path 7, thereby achieving both compactness and heat dissipation performance.

[0030] The first fin portion 28a, which is thermally connected to the first electronic component 10a, and the second fin portion 1c, which is thermally connected to the second electronic component 10b, are made of copper or a copper alloy, or aluminum or an alloy of aluminum and silicon. By using a material with excellent thermal conductivity in the portion specialized for heat dissipation, the thermal resistance from each electronic component to the cooling flow path 7 can be reduced, and cooling performance can be improved.

[0031] In the electronic control device 100, the plate-shaped member 3 is smaller in the in-plane direction than the sub-housing chassis 28 of the sub-housing 2, and the end 2b of the sub-housing 2 in the in-plane direction does not partially overlap the plate-shaped member 3 in the stacking direction. That is, the plate-shaped member 3 has the cutout 3d, which makes it easier to insert the tip of a removal jig 20 (described later in FIG. 13 ) for removing the sub-housing 2 into this cutout 3d, facilitating removal of the sub-housing 2. Furthermore, when the tip of the removal jig 20 is inserted, the tip of the removal jig 20 does not come into contact with the plate-shaped member 3. Even if the tip scratches the sub-housing 2 and the plate-shaped member 3, the seal portion between the plate-shaped member 3 and the main housing 1 is not affected, and the sub-housing 2 can be safely removed.

[0032] (Fig. 9) As shown in Fig. 9(a), it is assumed that the first electronic component 10a and the second electronic component 10b are arranged so that they are completely overlapping in the stacking direction. However, when mounted, as shown in Fig. 9(b), the centers of the first electronic component 10a and the second electronic component 10b may be at different positions in the stacking direction. However, this configuration is also possible with the present invention. Even in a case like Fig. 9(b), the positions of the heat-generating components can be dispersed, and the fin surface area can be increased by the amount of misalignment, thereby increasing the heat dissipation area. This improves cooling performance. Furthermore, the increased flexibility in the mounting position of each electronic component on each board simplifies design.

[0033] By adopting the above-described configuration of the present invention, each sub-housing 2 and the plate-like member 3 are fixed in contact with each other on a single independent plane, making it possible to equalize the surface pressure generated for each sub-housing 2. Furthermore, only the sealant is sandwiched between the members that make up the cooling flow path 7, eliminating gaps that would previously have occurred due to dimensional differences caused by finished product conditions. Therefore, even if the height of the surface of the plate-like member 3 that contacts the sub-housing 2 differs for each sub-housing 2, sealing can be ensured.

[0034] Furthermore, by making the heights of the sealing surface between the sub-housing 2 and the plate-like member 3 and the installation surface of the cooling fin 28c different in the stacking direction, the side portion 28b formed by the different heights can be fitted into the inner wall surface of the opening 3a of the plate-like member 3 for positioning, thereby preventing incorrect assembly.

[0035] Furthermore, by integrating the electric circuit consisting of electronic components and the like into a single sub-housing 2, it is possible to directly replace only the sub-housing 2 without opening the device by simply removing the sub-housing 2 from the bolt fixing, which contributes to reducing the cost of replacing components when upgrading ECU hardware.

[0036] (First Modification) (FIG. 10) The second fin portion 1c of the main housing 1 may be configured to accommodate a plurality of electronic components 10 together with one second fin portion 1c to promote heat dissipation, rather than being configured to be divided into portions for each electronic component 10 and provided within the cooling flow path 7.

[0037] (Second Modification) (FIG. 11) FIG. 11(a) is an external perspective view of an electronic control device 100 showing a second modification, and FIG. 11(b) is a cross-sectional view taken along the line A-A in FIG. 11(a). As shown in FIG. 11(a), it is not necessary for all of the sub-housings 2 to be fitted into the openings of the plate-shaped member 3. For example, if only one sub-housing 2 is mounted in the opening 3a (FIG. 3) of the plate-shaped member 3, a cover member 17 having a third fin portion 17b formed with a stepped surface 17a that fits into the inner wall surface of the opening 3a is attached to the remaining opening 3a. The third fin portion 17b is disposed within the cooling flow path 7, passing through the opening 3a.

[0038] The third fin portion 17b needs to have a structure similar to that of the first cooling fin portion 28a of the sub-housing 2. If the third fin portion 17b did not have such a structure and simply blocked the opening 3a, a space would be formed above the second fin portion 1c of the main housing 1. As a result, the refrigerant would flow through the space with a resistance smaller than that of the fins, reducing the flow rate of the refrigerant exchanging heat with the second fin portion 1c and reducing cooling performance. However, by providing the cover member 17 with a fin structure as described above, an appropriate flow rate of refrigerant can flow, ensuring heat dissipation.

[0039] Furthermore, by adopting a configuration using the cover member 17, it is possible to adjust the performance according to the size of the vehicle in which the common ECU is installed, and for example, since a small car has fewer functions at the time of purchase, it is possible to install a smaller number of sub-casings 2. Furthermore, it is easy to add or replace sub-casings 2 when upgrading.

[0040] (Third Modification) (FIG. 12) The cooling fins 28c of the first fin section 28a of the sub-casing 2 and the second fin section 1c of the main housing 1 may be arranged so that the tips of the fins fit into the gaps between each other and overlap each other. This allows the length of each fin section to be longer and the surface area to be increased, thereby improving the cooling effect.

[0041] (Fourth Modification, Fifth Modification) (FIG. 13) FIG. 13(a) is a cross-sectional view of an electronic control device 100 according to a fourth modification with a removal jig 20 attached thereto, and FIG. 13(b) is a plan view illustrating a sub-housing 2 mounted on a plate-shaped member 3 according to a fifth modification. As shown in FIG. 13(a), in order to make it easier to insert the tip of removal jig 20 used to remove sub-housing 2 into the end of sub-housing 2, the plate-shaped member 3, main-housing chassis 13, main-housing cover 15, and external wall surface may be configured so that there are no steps in the stacking direction. Also, as shown in FIG. 13(b), even if notch 3d is not formed in plate-shaped member 3, the size of each sub-housing 2 may be larger than the width direction of plate-shaped member 3 so that sub-housing 2 can be caught on the tip of removal jig 20.

[0042] (Sixth Modification) (FIG. 14) The notch 3d of the plate-shaped member 3 does not need to be formed for each opening 3a in which a sub-housing 2 is set as in FIG. 3, but only one notch 3d may be provided along the direction in which multiple sub-housings 2 are arranged on the plate-shaped member 3. This makes it easier to insert the tip of the removal jig 20 (FIG. 13) into the notch 3d.

[0043] According to the embodiment of the present invention described above, the following advantageous effects are achieved.

[0044] (1) An electronic control device (100) includes a plurality of detachable sub-housings (2), each of which has a board (9b) on which a first electronic component (10a) is mounted, a housing (2) that houses the board (9b), and a first fin (28a) that cools the first electronic component (10a), the electronic control device (100) includes a main board (9a) that is electrically connected to the plurality of sub-housings (2) via board-to-board connectors (8) and on which a second electronic component (10b) is mounted, and a main housing (1) that houses the main board (9a), a plate-like member (3) that is disposed between the plurality of sub-housings (2) and the main housing (1) and has openings (3a) that correspond to the plurality of sub-housings (2), the main housing (1) and the plate-like member (3) form a cooling flow path (7) through which a refrigerant flows, and the first fin (28a) is inserted through the openings (3a) and is disposed within the cooling flow path (7). This configuration makes it possible to provide an electronic control device (100) that achieves improved cooling performance, easier housing replacement, and ensures sealing performance.

[0045] (2) The center of the first electronic component 10a and the center of the second electronic component 10b are located at different positions in the stacking direction, which improves cooling performance.

[0046] (3) The main housing 1 has second fins 1c formed opposite the first fins 28a in the cooling flow path 7, and the first fins 28a and the second fins 1c overlap each other. This improves the cooling effect.

[0047] (4) At least one of the first fin portion 28a and the second fin portion 1c has a cylindrical fin shape, which improves cooling performance compared to plate-like fins.

[0048] (5) In the in-plane direction, the plate-like member 3 is smaller than the sub-housing 2, and the end of the sub-housing 2 in the in-plane direction does not partially overlap the plate-like member 3 in the stacking direction. This makes it easier to insert the tip of the removal jig 20, improving the ease of replacing the sub-housing 2. In addition, the sealing surface of the plate-like member 3 is not damaged.

[0049] (6) The sub-housing 2 has a stepped side surface 28b between the sealing surface 2a that adheres to the surface of the plate-like member 3 and the surface on which the cooling fins 28c of the first fin portion 28a are formed, and the stepped side surface 28b fits into the inner wall surface of the opening 3a. This makes it easy to position the sub-housing 2 relative to the plate-like member 3.

[0050] (7) The first fin portion 28a, which is thermally connected to the first electronic component 10a, and the second fin portion 1c, which is thermally connected to the second electronic component 10b, are made of copper or a copper alloy, or aluminum or an alloy of aluminum and silicon, thereby improving cooling performance.

[0051] (8) The board 9b and the main board 9a are electrically connected using the board-to-board connector 8 or a cable, and the board 9b receives power from the main board 9a. This contributes to the miniaturization of the sub-casing 2.

[0052] (9) The cover member 17 includes a third fin portion 17b having a stepped surface 17a that fits into the inner wall surface of the opening 3a, and the third fin portion 17b is inserted through the opening 3a and disposed in the cooling flow path 7. This allows performance adjustment while maintaining cooling performance, even when performing an update that reduces the number of sub-casings 2.

[0053] The present invention is not limited to the above-described embodiments, and various modifications and combinations of other configurations are possible without departing from the spirit of the present invention. Furthermore, the present invention is not limited to those having all of the configurations described in the above-described embodiments, and includes those in which some of the configurations are omitted.

[0054] REFERENCE SIGNS LIST 1 main housing 1c second fin portion 1d internal space 2 sub-housing 2a sealing surface 2b sub-housing end 2d internal space 3 plate-like member 3a opening 3b O-ring groove 3c through hole 3d cutout portion 4 sealing material 5 cooling water inlet pipe 5a pipe connection hole 6 cooling water outlet pipe 7 cooling flow path 8 inter-board connector 9a main board 9b board 10 electronic component 10a first electronic component 10b second electronic component 13 main housing chassis 13a O-ring groove 13b through hole 14 TIM 15 main housing cover 15a cooling water outlet hole 16 external connection connector 17 cover member 17a stepped surface 17b third fin portion 20 removal jig 23 sub-housing cover 24 connector 25 capacitor 27 External connection connector 28 Sub-housing chassis 28a First fin portion 28b Step side portion 28c Cooling fin 100 Electronic control device

Claims

1. An electronic control device comprising a plurality of detachable sub-housings, wherein the plurality of sub-housings have a board on which a first electronic component is mounted, a housing that houses the board, and a first fin portion that cools the first electronic component; a main board that is electrically connected to the plurality of sub-housings via board-to-board connectors and on which a second electronic component is mounted, and a main housing that houses the main board; a plate-like member that is arranged between the plurality of sub-housings and the main housing and has openings that respectively correspond to the plurality of sub-housings; the main housing and the plate-like member form a cooling flow path through which a refrigerant flows, and the first fin portion is inserted through the opening and arranged within the cooling flow path.

2. The power conversion device according to claim 1, wherein the center of the first electronic component and the center of the second electronic component are at different positions in the stacking direction.

3. An electronic control device as described in claim 1, wherein the main housing has a second fin portion formed opposite the first fin portion within the cooling flow path, and the first fin portion and the second fin portion overlap each other.

4. The electronic control device according to claim 3, wherein at least one of the first fin portion and the second fin portion has a cylindrical fin shape.

5. An electronic control device according to claim 1, wherein the plate-like member is smaller than the sub-housing in the in-plane direction, and the end of the sub-housing in the in-plane direction does not partially overlap the plate-like member in the stacking direction.

6. An electronic control device as described in claim 1, wherein the sub-housing has a stepped side portion between a sealing surface that adheres to the surface of the plate-like member and a surface on which the cooling fins of the first fin portion are formed, and the stepped side portion is fitted into the inner wall surface of the opening.

7. An electronic control device as described in claim 3 or 4, wherein the first fin portion thermally connected to the first electronic component and the second fin portion thermally connected to the second electronic component are made of copper or a copper alloy, or aluminum or an alloy of aluminum and silicon.

8. An electronic control device according to claim 1, wherein the board and the main board are electrically connected using the board-to-board connector or cable, and the board is supplied with power from the main board.

9. An electronic control device as described in claim 1, further comprising a cover member having a third fin portion with a stepped surface that fits into the inner wall surface of the opening, the third fin portion being inserted through the opening and positioned within the cooling flow path.

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