Electronic control device

Abstract

This electronic control device comprises: an enclosure having a body section in which is formed a coolant channel through which a coolant passes; a first circuit board; a second circuit board; and a connector. The first circuit board is disposed in the enclosure and has mounted thereon an electronic component facing the coolant channel. The second circuit board is disposed on the opposite side of the enclosure from the first circuit board and has mounted thereon an electronic component facing the coolant channel. The connector electrically connects the first circuit board and the second circuit board. A through-opening through which to insert the connector is formed in the body section of the enclosure. The through-opening is located in the projected plane of the coolant channel as seen when viewing the enclosure from a direction orthogonal to the direction in which the first circuit board and second circuit board face each other.

Description

Electronic control unit

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

[0002] In recent years, the amount of heat generated by electronic components mounted on circuit boards has been increasing. Therefore, a water-cooling method using cooling water has been proposed as a method for cooling electronic components mounted on multiple circuit boards. An example of a conventional electronic control device of this type is described in Patent Document 1.

[0003] Patent Document 1 describes a technology including a box-shaped housing, at least one pair of mounting boards disposed within the housing and having electrical elements mounted thereon, and a cooling body having a flow path through which a cooling medium flows. Patent Document 1 also describes that each mounting board is a double-sided mounting board, and that a first heat-generating element mounted on a first mounting surface facing the cooling body is thermally connected to the cooling body. A second heat-generating element mounted on a second mounting surface located opposite the cooling body is thermally connected to the housing.

[0004] Japanese Patent Application Laid-Open No. 2021-180250

[0005] However, in the technology described in Patent Document 1, the connector that electrically connects the two circuit boards is located away from the cooling water flow path that is located between the two circuit boards, which results in a problem in that the distance between the connector and the heat-generating electronic components is large, and the wiring distance connecting the connector and the electronic components becomes long.

[0006] In consideration of the above problems, an object of the present invention is to provide an electronic control device that can shorten the wiring distance between the connector and an electronic component that is a heat-generating component.

[0007] To solve the above problems and achieve the object, an electronic control device includes a housing having a main body portion in which a coolant flow path through which coolant passes, a first circuit board, a second circuit board, and a connector. The first circuit board is disposed in the housing and has electronic components mounted thereon that face the coolant flow path. The second circuit board is disposed on the opposite side of the housing from the first circuit board and has electronic components mounted thereon that face the coolant flow path. The connector electrically connects the first circuit board and the second circuit board. The main body portion of the housing has a through opening formed therein that penetrates the housing in a direction perpendicular to the direction in which the first circuit board and the second circuit board face each other, and through which the connector is inserted. The through opening is located within the projection plane of the coolant flow path when the housing is viewed in a direction perpendicular to the direction in which the first circuit board and the second circuit board face each other.

[0008] According to the electronic control device having the above configuration, it is possible to shorten the wiring distance between the connector and the electronic component, which is a heat-generating component.

[0009] Fig. 1 is an exploded perspective view showing an electronic control device according to a first embodiment; Fig. 2 is a perspective view showing a housing of the electronic control device according to the first embodiment; Fig. 3 is a plan view showing an electronic control device according to the first embodiment; Fig. 4 is a cross-sectional view showing an electronic control device according to the first embodiment; Fig. 5 is a plan view showing an electronic control device according to a second embodiment; Fig. 6 is a plan view showing a housing of an electronic control device according to a third embodiment; Fig. 7 is a cross-sectional view showing an electronic control device according to the third embodiment;

[0010] Hereinafter, an embodiment of an electronic control device will be described with reference to Figures 1 to 7. Note that common members in each figure are given the same reference numerals.

[0011] 1. First Embodiment First, the configuration of an electronic control device according to a first embodiment (hereinafter referred to as "this embodiment") will be described with reference to Figures 1 to 4. Figure 1 is an exploded perspective view showing the electronic control device, Figure 2 is a perspective view showing the housing of the electronic control device, Figure 3 is a plan view showing the electronic control device, and Figure 4 is a cross-sectional view showing the electronic control device.

[0012] 1 to 4, the electronic control unit 1 is mounted on, for example, an automobile and has an electronic circuit for controlling the automobile. As shown in Fig. 1 to 4, the electronic control unit 1 includes a first cover 2, a second cover 3, a first circuit board 4, a second circuit board 5, and a housing 6 formed in a substantially rectangular shape.

[0013] The first cover 2 and the second cover 3 are formed in a generally flat plate shape. The first cover 2 is disposed opposite one surface of the housing 6, and the second cover 3 is disposed opposite the other surface of the housing 6. The first cover 2 and the second cover 3 are fixed to the housing 6.

[0014] A first circuit board 4 is disposed on one side of the housing 6, and a second circuit board 5 is disposed on the other side of the housing 6. The first circuit board 4 is housed in a space formed between the housing 6 and the first cover 2. The second circuit board 5 is housed in a space formed between the housing 6 and the second cover 3.

[0015] The first circuit board 4 is mounted with a plurality of first electronic components 10 and second electronic components 11, which are heat-generating components. The first electronic components 10 may be, for example, a system-on-chip (SOC). The second electronic components 11 are electronic components that generate less heat than the first electronic components 10, such as a capacitor. The first circuit board 4 is also provided with a connector 8 for electrical connection with a connector 14 provided on the second circuit board 5. The connector 8 protrudes perpendicularly from one surface of the first circuit board 4 toward the second circuit board 5. Similar to the first circuit board 4, the second circuit board 5 is also mounted with a plurality of third electronic components 12, which are heat-generating components.

[0016] Next, the housing 6 in which the above-mentioned first circuit board 4 and second circuit board 5 are disposed will be described. The housing 6 is formed in a rectangular parallelepiped shape having a substantially rectangular shape. The housing 6 has a hollow main body 21 and a side wall 22. The side wall 22 is formed to surround the periphery of the main body 21. The side wall 22 is connected to the main body 21 substantially perpendicularly. The first cover 2 is fixed to one end of the side wall 22. The second cover 3 is fixed to the other end of the side wall 22.

[0017] A cooling water inlet 25 and a cooling water outlet 26 are provided on the side wall 22, which is disposed at one longitudinal end of the main body 21. The cooling water inlet 25 and the cooling water outlet 26 are connected to a cooling water flow path 24 formed in the main body 21, which will be described later. The cooling water inlet 25 is disposed on one side in the lateral direction of the main body 21, and the cooling water outlet 26 is disposed on the other side in the lateral direction of the main body 21. Cooling water is sent to the cooling water inlet 25 from a pump (not shown). The cooling water then flows into the cooling water flow path 24 via the cooling water inlet 25. The cooling water that has passed through the cooling water flow path 24 is discharged to the outside from the cooling water outlet 26.

[0018] A first circuit board 4 is disposed between the first cover 2 and the main body 21. A second circuit board 5 is disposed between the second cover 3 and the main body 21. The first circuit board 4 is disposed opposite one surface of the main body 21 that faces the first cover 2. The second circuit board 5 is disposed opposite the other surface of the main body 21 that faces the second cover 3.

[0019] 2, the main body 21 is formed with a through opening 23 and a cooling water flow path 24. The cooling water flow path 24 is a recess that is recessed from the other surface of the main body 21 toward one surface. Therefore, the surface of the cooling water flow path 24 that faces the second cover 3 and the second circuit board 5 is open. Also, as shown in FIGS. 1 and 4, a substantially flat lid 7 is fixed to the main body 21. The lid 7 is fixed to the main body 21 and closes the opening of the cooling water flow path 24 that faces the second circuit board 5.

[0020] Cooling water is fed into the cooling water flow path 24 via a cooling water inlet 25. The cooling water flow path 24 serves as a heat dissipation destination for the first electronic component 10 and the third electronic component 12, which are heat-generating components.

[0021] 2 and 3, a partition 28 is formed in the cooling water flow path 24. The partition 28 protrudes substantially perpendicularly from the bottom surface of the cooling water flow path 24 toward the opening on the second circuit board 5 side. The partition 28 is a protrusion that extends a predetermined length along the longitudinal direction from one end of the cooling water flow path 24 in the longitudinal direction. The partition 28 is formed closer to one side than the intermediate portion of the cooling water flow path 24 in the lateral direction.

[0022] The cooling water flow path 24 is formed with an upstream portion 24a, a downstream portion 24b, and a turning portion 24c by the partition portion 28. The upstream portion 24a is formed on one side of the partition portion 28 in the short direction of the cooling water flow path 24. The upstream portion 24a communicates with the cooling water inlet portion 25. The downstream portion 24b is formed on the other side of the partition portion 28 in the short direction of the cooling water flow path 24. The downstream portion 24b communicates with the cooling water outlet portion 26.

[0023] As described above, the partition portion 28 is formed closer to one side than the intermediate portion in the short direction of the cooling water flow path 24. Therefore, in the cooling water flow path 24, the flow path width of the upstream portion 24a is formed wider than the flow path width of the downstream portion 24b. That is, the cooling space of the upstream portion 24a of the cooling water flow path 24 is wider than the cooling space of the downstream portion 24b. This makes it possible to improve the cooling performance of the upstream portion 24a of the cooling water flow path 24 compared to the downstream portion 24b.

[0024] The upstream portion 24a and the downstream portion 24b are connected to a turning portion 24c at the other end in the longitudinal direction of the cooling water flow path 24. The cooling water that has flowed in from the cooling water inlet portion 25 moves along the upstream portion 24a from one end to the other end in the longitudinal direction of the cooling water flow path 24. The cooling water that has reached the turning portion 24c is turned back by the turning portion 24c, so that its traveling direction is changed from the other end to one end in the longitudinal direction of the cooling water flow path 24. The cooling water then moves along the downstream portion 24b from the other end to the one end in the longitudinal direction of the cooling water flow path 24 and is discharged to the outside from the cooling water discharge portion 26.

[0025] 3 and 4 , the upstream portion 24a of the cooling water flow path 24 is formed to face the first electronic component 10, which generates a large amount of heat, on the first circuit board 4. The upstream portion 24a is also formed to face the third electronic component 12, which generates a large amount of heat, on the second circuit board 5. The downstream portion 24b of the cooling water flow path 24 is formed to face the second electronic component 11, which generates a small amount of heat, on the first circuit board 4. In this way, by arranging the upstream portion 24a of the cooling water flow path 24 to face the first electronic component 10 and the third electronic component 12, which are heat-generating components, the cooling efficiency can be improved. Furthermore, because the flow path volume of the upstream portion 24a is larger than the flow path volume of the downstream portion 24b, the first electronic component 10 and the third electronic component 12, which are heat-generating components, can be cooled more efficiently.

[0026] 3, a protruding portion 21a is formed on the main body 21. The protruding portion 21a is formed to protrude inward in the short direction from the outer edge of the long side of the cooling water flow path 24. When the main body 21 is viewed from a direction facing the second cover 3, the protruding portion 21a is formed within the cooling water flow path 24. A through opening 23 is formed in the protruding portion 21a.

[0027] The through opening 23 is a through hole formed continuously from one surface to the other surface of the main body 21. As shown in Fig. 4, the through opening 23 is disposed within the projection plane of the cooling water flow path 24 when the housing 6 is viewed from the short-side direction and the long-side direction, which are directions perpendicular to the direction in which the first circuit board 4 and the second circuit board 5 face each other. Furthermore, the protruding portion 21a is formed within the cooling water flow path 24 when the main body 21 is viewed from the direction facing the second cover 3.

[0028] The connector 8 provided on the first circuit board 4 is inserted into the through opening 23. Furthermore, the through opening 23 faces the connector 14 provided on the second circuit board 5. A notch is formed in the lid 7 at a location facing the through opening 23. This allows the connector 8 of the first circuit board 4 to be connected to the connector 14 of the second circuit board 5 via the through opening 23.

[0029] Furthermore, by forming the through opening 23 above the cooling water flow path 24, the connectors 8, 14 are disposed closer to the first electronic component 10 and the third electronic component 12 that face the cooling water flow path 24. As a result, according to the electronic control device 1 of this example, the connectors 8, 14 can be mounted closer to the first electronic component 10 and the third electronic component 12 than in conventional electronic control devices in which the connectors 8, 14 are disposed at locations farther away from the cooling water flow path 24. As a result, the wiring distance between the connector 8 and the first electronic component 10 can be shortened.

[0030] By shortening the wiring distance between the connector 8 and the first electronic component 10, a margin for transmission loss is created. Therefore, the shortened length of the wiring between the connector 8 and the first electronic component 10 can be replaced with the length of the connector 8 protruding in the height direction from the first circuit board 4. In other words, the electronic control device 1 of this example allows the use of a connector 8 that is taller than conventional electronic control devices.

[0031] Increasing the height of the connector 8 also makes it possible to increase the thickness of the main body 21 through which the connector 8 passes. This makes it possible to increase the length of the cooling water flow path 24 formed in the main body 21 in the height direction, which is the direction facing the first circuit board 4 and the second circuit board 5. As a result, according to the electronic control device 1 of this example, it is possible to increase the overall volume of the cooling water flow path 24, thereby improving cooling performance.

[0032] 2. Second Embodiment Next, an electronic control device according to a second embodiment will be described with reference to Fig. 5. Fig. 5 is a plan view showing the electronic control device according to the second embodiment.

[0033] The electronic control device according to the second embodiment differs from the electronic control device 1 according to the first embodiment in the position of the through opening through which the connector 8 is inserted. Therefore, parts common to the electronic control device 1 according to the first embodiment are denoted by the same reference numerals and redundant explanations will be omitted.

[0034] 5, the electronic control device according to the second embodiment includes a housing 6B having a main body 41 formed with a cooling water flow path 44. The cooling water flow path 44 is divided by a partition 48 into an upstream portion 44a, which is the upstream portion 31 of the cooling water flow path, a downstream portion 44b, which is the downstream portion 32, and a turn-back portion 44c. The upstream portion 44a of the cooling water flow path 44 is disposed opposite the first electronic component 10, which is a heat-generating component. The downstream portion 44b of the cooling water flow path 44 is disposed opposite the second electronic component 11, which generates a small amount of heat.

[0035] Furthermore, a cylindrical partition wall 43 is formed in the upstream portion 44a of the cooling water flow path 44. The partition wall 43 protrudes substantially perpendicularly from the bottom surface of the cooling water flow path 44 toward the opening on the second circuit board 5 side. That is, the partition wall 43 protrudes in a direction facing the first circuit board 4 and the second circuit board 5. The end of the cylindrical hole of the partition wall 43 on the bottom surface side of the cooling water flow path 44 is open. Therefore, the cylindrical hole of the partition wall 43 serves as a through opening that penetrates the main body 21. The connector 8 is inserted into the cylindrical hole of the partition wall 43. An opening through which the connector 8 is inserted is formed in a portion of the lid (not shown) that faces the cylindrical hole of the partition wall 43.

[0036] As described above, according to the electronic control device of the second embodiment, similarly to the electronic control device 1 of the first embodiment, a through opening through which the connector 8 is inserted is formed in the cooling water flow path 44 facing the first electronic component 10. As a result, according to the electronic control device of the second embodiment, it is possible to shorten the wiring distance between the connector 8 and the first electronic component 10.

[0037] The other configurations are the same as those of the electronic control device 1 according to the first embodiment, and therefore description thereof will be omitted. The electronic control device having such a housing 6B can also obtain the same effects as those of the electronic control device 1 according to the first embodiment described above.

[0038] 3. Third Embodiment Next, an electronic control device according to a third embodiment will be described with reference to Fig. 6 and Fig. 7. Fig. 6 is a plan view showing the housing of the electronic control device according to the third embodiment, and Fig. 7 is a cross-sectional view showing the electronic control device according to the third embodiment.

[0039] The electronic control device according to the third embodiment differs from the electronic control device 1 according to the first embodiment in that heat dissipation fins are provided in the cooling water flow path. Therefore, the protective member will be described here, and parts common to the electronic control device 1 according to the first embodiment will be assigned the same reference numerals and redundant description will be omitted.

[0040] 6 and 7 , the electronic control device 1C includes a first cover 2, a second cover 3, a first circuit board 4 and a second circuit board 5 on which electronic components 10 are mounted, a housing 6C, and a lid 7C. Thermal grease 13 is interposed between the first electronic component 10 mounted on the first circuit board 4 and one surface of the main body 51 of the housing 6C. Thermal grease 13 is also interposed between the third electronic component 12 mounted on the second circuit board 5 and the lid 7C.

[0041] A cooling water flow path 54 is formed in the main body 51 of the housing 6C. The cooling water flow path 54 is divided by a partition 58 into an upstream portion 54a which is the upstream 31 of the cooling water flow path, a downstream portion 54b which is the downstream 32, and a turning portion 54c which is the turning point 33. The upstream portion 54a of the cooling water flow path 54 is disposed opposite the first electronic component 10, which is a heat-generating component. The upstream portion 54a communicates with a cooling water inlet portion 45 provided in the side wall 52 of the housing 6C.

[0042] Additionally, the upstream portion 54a is provided with a plurality of heat dissipation fins 59. The plurality of heat dissipation fins 59 protrude substantially perpendicularly from the bottom surface of the cooling water flow path 54 in a direction facing the second cover 3. The plurality of heat dissipation fins 59 extend along the longitudinal direction of the main body portion 51, which is the direction in which the cooling water flows. The plurality of heat dissipation fins 59 are arranged at intervals in the lateral direction of the main body portion 51. Furthermore, the plurality of heat dissipation fins 59 are arranged at a location in the upstream portion 54a facing the first electronic component 10.

[0043] Furthermore, a plurality of heat dissipation fins 61 are provided on the surface of the lid 7C facing the cooling water flow path 54. The plurality of heat dissipation fins 61 protrude substantially perpendicularly from the facing surface of the lid 7C toward the cooling water flow path 54. The plurality of heat dissipation fins 61 extend along the longitudinal direction of the main body 51, which is the direction in which the cooling water flows. The plurality of heat dissipation fins 61 are arranged at intervals in the lateral direction of the lid 7C. The plurality of heat dissipation fins 61 are also arranged at a location on the lid 7C facing the third electronic component 12.

[0044] In this way, by providing a plurality of heat dissipation fins 59 and 61, heat from the first electronic component 10 and the third electronic component 12 can be efficiently transferred to the cooling water flowing through the cooling water flow path 54.

[0045] Here, in the cooling water flow path 54, the flow path width of the upstream portion 54a is formed wider than the flow path width of the downstream portion 54b. Therefore, the cooling performance of the upstream portion 54a can be made higher than the cooling performance of the downstream portion 54b. Note that, by increasing the flow path width, the upstream portion 54a experiences less pressure loss than the downstream portion 54b.

[0046] In contrast, in the electronic control device 1C according to the third embodiment, multiple heat dissipation fins 59, 61 are arranged at intervals in a direction perpendicular to the direction of the coolant flow in the upstream portion 54a where the flow path width is wide. These multiple heat dissipation fins 59, 61 can equalize the pressure loss in the upstream portion 54a and the pressure loss in the downstream portion 54b of the coolant flow path 54. As a result, the first electronic component 10 and the third electronic component 12, which are heat-generating components, can be cooled efficiently.

[0047] The other configurations are the same as those of the electronic control unit 1 according to the first embodiment, and therefore description thereof will be omitted. The electronic control unit 1C according to the third embodiment can also obtain the same effects as those of the electronic control unit 1 according to the first embodiment described above.

[0048] The present invention is not limited to the embodiments described above and shown in the drawings, and various modifications are possible within the scope of the invention as defined in the claims. It is also possible to replace a part of the configuration of one embodiment with a configuration of another embodiment, or to add a configuration of another embodiment to a configuration of one embodiment. Furthermore, it is also possible to add, delete, or replace a part of the configuration of another embodiment with another configuration.

[0049] In the above-described embodiment, an example has been described in which the number of connectors electrically connecting the first circuit board 4 and the second circuit board 5 is one, but this is not limited thereto, and the first circuit board 4 and the second circuit board 5 may be connected by a plurality of connectors. In this case, it is sufficient that a through hole through which at least one of the plurality of connectors is inserted is formed in the cooling water flow path.

[0050] Furthermore, the number of first circuit boards 4 and second circuit boards 5 is not limited to one each, and a plurality of first circuit boards 4 and second circuit boards 5 may be provided.

[0051] In this specification, the words "parallel" and "orthogonal" are used, but these do not mean only "parallel" and "orthogonal" in the strict sense, but also include "parallel" and "orthogonal" and may also mean a "substantially parallel" or "substantially orthogonal" state within a range in which the functions can be exerted.

[0052] DESCRIPTION OF SYMBOLS 1, 1C...Electronic control device, 2...First cover, 3...Second cover, 4...First circuit board, 5...Second circuit board, 6, 6B, 6C...Housing, 7, 7C...Lid, 8, 14...Connector, 10...First electronic component (heat-generating component), 11...Second electronic component, 12...Third electronic component (heat-generating component), 13...Thermal grease, 21, 41, 51...Main body, 21a...Protruding portion, 22, 52...Side wall portion, 23...Through opening, 24, 44, 54...Cooling water flow path, 24a, 44a, 54a...Upstream portion, 24b, 44b, 54b...Downstream portion, 24c, 44c, 54c...Folded portion, 25, 45...Cooling water inlet portion, 26...Cooling water outlet portion, 28, 48, 58...Partition portion, 31...upstream, 32...downstream, 33...turning point, 43...partition wall portion, 59, 61...heat dissipation fin

Claims

1. An electronic control device comprising: a housing having a main body portion in which a cooling water flow path through which cooling water passes is formed; a first circuit board disposed in the housing and on which electronic components facing the cooling water flow path are mounted; a second circuit board disposed on the side of the housing opposite to the first circuit board and on which electronic components facing the cooling water flow path are mounted; and a connector that electrically connects the first circuit board and the second circuit board, wherein a through-opening through which the connector is inserted is formed in the main body portion of the housing so as to penetrate the housing in a direction orthogonal to the direction in which the first circuit board and the second circuit board face each other, and the through-opening is disposed within the projection plane of the cooling water flow path when the housing is viewed from a direction orthogonal to the direction in which the first circuit board and the second circuit board face each other.

2. The electronic control device according to claim 1, wherein a projecting portion in which the through-opening is formed is formed in the main body portion, and the projecting portion is formed to project toward the inside of the cooling water flow path.

3. The electronic control device according to claim 1, wherein a partition portion projecting in the direction in which the first circuit board and the second circuit board face each other is formed inside the cooling water flow path, the partition portion is formed in a cylindrical shape, a cylindrical hole of the partition portion penetrates the main body portion, and the cylindrical hole of the partition portion serves as the through-opening through which the connector is inserted.

4. The electronic control device according to claim 1, wherein the cooling water flow path has an upstream portion on the upstream side in the direction in which the cooling water flows and a downstream portion on the downstream side in the direction in which the cooling water flows, and the upstream portion faces a heat-generating component that generates heat among a plurality of electronic components mounted on the first circuit board and the second circuit board.

5. The electronic control device according to claim 4, wherein the flow path width of the upstream portion in the cooling water flow path is formed wider than the flow path width of the downstream portion.

6. The electronic control device according to claim 1, wherein the cooling water flow path is a recess formed in the main body portion, and the electronic control device further includes a lid that closes an opening of the recess.

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