Electronic Control Unit

Abstract

To provide a cooling technique capable of simultaneously dissipating heat from a plurality of electronic components.SOLUTION: An electronic control device includes a housing with fins, and a cooling mechanism having a fin cover for forming a coolant flow path on the fins, and on a circuit board in the housing, a first electronic component and a second electronic component are in contact with the base surface of the housing via a heat transfer member, and the housing includes a region A having the first electronic component and a region B having the second electronic component, the flow path is longer in the region B than in the region A, and the inner side of the fin cover in the region A has a convex protrusion, and the flow path is formed in a comb shape.SELECTED DRAWING: Figure 1

Description

[Technical field]

[0001] The present disclosure relates to an electronic control device, and in particular to a technology that is effective when applied to an electronic control device that includes a plurality of semiconductor elements that generate heat. [Background technology]

[0002] Vehicles such as automobiles are equipped with electronic control units (also called ECUs) for engine control, motor control, automatic transmission control, and the like. Some electronic control units are equipped with semiconductor elements (ICs) that generate high heat. Such electronic components such as semiconductor elements that generate high heat are usually placed between a circuit board (also called a printed circuit board) and a housing having fins for heat dissipation. A known structure is to form the housing from a material with high thermal conductivity such as metal, and to use an air-cooling fan to flow cooling air as a refrigerant between the fins for heat dissipation provided on the housing to cool the heat generated by the electronic components.

[0003] Proposals for cooling electronic components such as semiconductor elements include JP 2013-131520 A, JP 2019-47028 A, JP 06-314759 A, and JP 2018-32710 A. [Prior art documents] [Patent documents]

[0004] [Patent Document 1] JP 2013-131520 A [Patent Document 2] JP 2019-47028 A [Patent Document 3] Japanese Patent Application Publication No. 06-314759 [Patent Document 4] JP 2018-32710 A Summary of the Invention [Problem to be solved by the invention]

[0005] In order to realize high-performance ECUs for autonomous driving (AD) and advanced driver-assistance systems (ADAS), multiple ICs that generate high heat may be mounted on the ECU's printed circuit board. When cooling multiple ICs with a single cooling fan, it was found that uneven heat dissipation occurs among the multiple ICs because the flow paths between the fins (pressure loss) differ depending on the relative positions of each IC and the fan and the shape of the housing.

[0006] In addition, in order to reduce costs, the heat dissipation fins are sometimes made of aluminum die cast (ADC). In this case, it was found that the flow passage between the fins could not be narrowed due to design constraints, and the heat dissipation performance of multiple ICs deteriorates.

[0007] An object of the present disclosure is to provide a cooling technique that enables heat to be dissipated from multiple electronic components simultaneously.

[0008] Other objects and novel features will become apparent from the description of this specification and the accompanying drawings. [Means for solving the problem]

[0009] A brief summary of representative aspects of this disclosure is as follows.

[0010] According to one embodiment, the electronic control device includes a housing having fins, and a cooling mechanism having a fin cover on the fins for forming a flow path of a coolant; a coolant circulation device for circulating a coolant through the flow path; The circuit board in the housing is provided with 1 of The electronic component and the second electronic component are in contact with a base surface of the housing via a heat transfer member, and the housing is 1 of a region A having an electronic component and a region B having a second electronic component; the flow paths and the fins in region A are provided along a first direction, the flow paths and the fins in region B are provided along a second direction intersecting the first direction, region A and the refrigerant circulation device are disposed along the first direction, and region B and the refrigerant circulation device are disposed along the second direction, The flow passage is longer in the region B than in the region A, and the inner side of the fin cover in the region A has a convex protrusion, and the flow passage is formed in a comb shape. The inside of the fin cover in the region B does not have a convex protrusion. . Effect of the Invention

[0011] According to the above-described embodiment, it is possible to provide a cooling technique that enables a plurality of electronic components to simultaneously dissipate heat without causing unevenness in heat dissipation. Problems, configurations and effects other than those described above will become apparent from the following description of the preferred embodiment of the invention. [Brief description of the drawings]

[0012] [Figure 1] 1 is an external perspective view of an electronic control device according to an embodiment; [Diagram 2] FIG. 2 is an external perspective view of the electronic control device shown in FIG. 1 with a fin cover removed. [Diagram 3] FIG. 3 is a top view of the electronic control device shown in FIG. 2 . [Figure 4] 2 is a cross-sectional view taken along line II of the electronic control device shown in FIG. 1. [Diagram 5] 2 is a cross-sectional view taken along line II-II of the electronic control device shown in FIG. 1. [Figure 6] 5 is an enlarged view of a portion R of the electronic control device shown in FIG. 4, and is a cross-sectional view illustrating a fin cover according to a first configuration example. [Figure 7] 5 is an enlarged view of a portion R of the electronic control device shown in FIG. 4, and is a cross-sectional view illustrating a fin cover according to a second configuration example. [Figure 8] FIG. 2 is a top view of a fin cover of the electronic control device shown in FIG. 1 . [Figure 9] 1. FIG. 4 is a top view of a modified example of the fin cover of the electronic control device shown in FIG. [Figure 10] 10 is a cross-sectional view of the electronic control device along line III-III shown in FIG. 9 in which the fin cover of FIG. 9 is attached. [Figure 11] FIG. 4 is a top view of an electronic control device according to a first modified example. [Figure 12] FIG. 11 is a top view of an electronic control device according to a second modified example. [Figure 13] FIG. 4 is a diagram showing an equation for pressure loss used in the simulation. [Figure 14]FIG. 4 is an explanatory diagram of an electronic control device according to an embodiment used in a simulation. [Figure 15] FIG. 4 is an explanatory diagram of an electronic control device according to a comparative example used in a simulation. [Figure 16] 11A and 11B are comparative diagrams illustrating simulation results. [Figure 17] FIG. 11 is a diagram showing a specific numerical example of a simulation result. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0013] 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 appropriate omissions and simplifications have been made for clarity of explanation. The present invention can be implemented in various other forms. Unless otherwise specified, each component may be singular or plural. 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. When there are multiple components having the same or similar functions, they may be described by using the same reference numerals with different subscripts. However, when there is no need to distinguish between these multiple components, the subscripts may be omitted.

[0014] (Embodiment) Hereinafter, an embodiment will be described with reference to Figs. 1 to 7. Fig. 1 is an external perspective view of an electronic control device according to an embodiment. Fig. 2 is an external perspective view of the electronic control device shown in Fig. 1 with a fin cover removed. Fig. 3 is a top view of the electronic control device shown in Fig. 2. Fig. 4 is a cross-sectional view of the electronic control device taken along line II in Fig. 1. Fig. 5 is a cross-sectional view of the electronic control device taken along line II-II in Fig. 1. Fig. 6 is an enlarged view of part R of the electronic control device shown in Fig. 4, and is a cross-sectional view illustrating a fin cover according to a first configuration example. Fig. 7 is an enlarged view of part R of the electronic control device shown in Fig. 4, and is a cross-sectional view illustrating a fin cover according to a second configuration example.

[0015] The electronic control device 100 has a housing 20 including an upper housing 1 and a lower housing 2, a fin cover 8 provided so as to cover the upper side of heat dissipation fins 6 provided on the upper housing 1, and an air-cooled fan 10 for cooling attached to the upper housing 1. The housing has a forced air-cooling structure provided with the air-cooled fan 10. The air-cooled fan 10 can be considered as a refrigerant circulation device for circulating air, which is a refrigerant.

[0016] The upper housing 1 and the lower housing 2 are fixed by fastening members such as screws (not shown). Inside the housing, a circuit board (substrate) 3, a plurality of electronic components 4 including semiconductor elements such as a data processing device and a microprocessor (see Figs. 3 and 4: a first electronic component 4a and a second electronic component 4b), a heat transfer material (heat transfer section) 5 such as grease, and the like are housed. As shown in Figs. 1 and 4, a portion of the fin cover 8 has a plurality of protrusions 9 formed on the inner side (lower side) thereof, which are convex and facing downward. The plurality of protrusions 9 are structured to have a series of parallel protrusions 9 in the shape of comb teeth, and are configured so that one protrusion 9 is disposed between a pair (two) of fins 6.

[0017] The upper housing 1 is formed of a metal material with excellent thermal conductivity such as aluminum (e.g., ADC12). The upper housing 1 can be formed of sheet metal such as iron, or nonmetallic materials such as resin materials and CFRP, to reduce costs and weight. As shown in Figs. 1, 2, and 4, the upper housing 1 is formed in a box shape with side walls around it and an open lower surface (circuit board 3 side). The upper housing 1 is provided with a plurality of bosses 7 protruding toward the circuit board 3 (see Fig. 4). The circuit board 3 is fixed to the upper housing 1 by screws (not shown). The upper surface of the upper housing 1 is provided with a plurality of plate-shaped heat dissipation fins 6 protruding upward. The heat dissipation fins 6 and the bosses 7 are integrally formed with the upper housing 1 by casting such as die casting. However, the heat dissipation fins 6 and the bosses 7 may be fabricated as separate members from the upper housing 1 and attached to the upper housing.

[0018] As shown in Fig. 4, electronic components 4a and 4b are mounted on a circuit board 3, and a boss portion 7 protruding toward the circuit board 3 is formed on the upper inner surface of the upper housing 1. A heat transfer material (heat transfer member) 5 is provided between the boss portion 7 of the upper housing 1 and the electronic components 4a and 4b, and the electronic components 4a and 4b are in contact with the lower side (lower surface) of the base surface 1A of the upper housing 1 via the heat transfer material 5. This allows the heat of the electronic components 4a and 4b to be dissipated from the heat dissipation fins 6 provided on the upper side (upper surface) of the base surface 1A of the upper housing 1 via the heat transfer material 5 and the boss portion 7.

[0019] The lower housing 2 is made of a metal material with excellent thermal conductivity such as aluminum, similar to the upper housing 1. The lower housing 2 can be made of sheet metal such as iron, or a non-metal material such as a resin material, similar to the upper housing 1, to reduce costs and weight.

[0020] The fin cover 8 is made of a metal material with excellent thermal conductivity such as aluminum, similar to the upper housing 1. The fin cover 8 can also be made of sheet metal such as iron, or a non-metal material such as a resin material, similar to the upper housing 1, to reduce cost and weight. The fin cover 8 is provided on the fins 6 and constitutes a cooling mechanism for forming a flow path for the refrigerant.

[0021] As shown in Figs. 1, 2, and 3, the housing 20 (upper housing 1, lower housing 2) of the electronic control device 100 has a rectangular shape when viewed from above (in a top view). In this example, the housing 20 (upper housing 1, lower housing 2) has a quadrangular shape having four sides. As shown in Fig. 3, the housing 20 (upper housing 1, lower housing 2) has a first side S1, a second side S2 facing the first side S1, a third side S3 provided between the first side S1 and the second side S2, and a fourth side S4 facing the third side S3. In the example of Fig. 3, the length of the first side S1 is the same as the second side S2 and is shorter than the lengths of the third side S3 and the fourth side S4. In other words, the length of the third side S3 is the same as the fourth side S4 and is longer than the lengths of the first side S1 and the second side S2. The first side S1 and the second side S2 are provided in a first direction X, and the third side S3 and the fourth side S4 are provided in a second direction Y different from the first direction X.

[0022] The cooling fan 10 has a rectangular shape when viewed from above. In the example of Figs. 1, 2, and 3, the cooling fan 10 has a square shape when viewed from above. The cooling fan 10 is mounted in one corner region of the rectangular upper housing 1, that is, in a corner region CN where a first side S1 and a third side S3 intersect. The fan 10 is used to simultaneously cool two electronic components 4a and 4b using air as a refrigerant. The cooling air for the electronic component 4a flows in a first direction X (also referred to as a first flow path direction) in a region A (also referred to as a first region) through a first path length of a distance LA based on the formation direction of a plurality of heat dissipation fins 6 provided on the upper side of the electronic component 4a. The cooling air for the electronic component 4b flows in a second direction Y (also referred to as a second flow path direction Y) different from the first direction X in a region B (also referred to as a second region) based on the formation direction of the multiple heat dissipation fins 6 provided on the upper side of the electronic component 4b, over a path length of a distance LB longer than the distance LA (LB>LA). Here, it can be said that the distance LA corresponds to the length of the heat dissipation fin 6 in the region A, and the distance LB corresponds to the length of the heat dissipation fin 6 in the region B. In the example of FIG. 3, the first direction X and the second direction Y intersect, and more specifically, the first direction X and the second direction Y are perpendicular to each other.

[0023] In other words, when viewed from above, the housing 20 has the fan 10 and the region A arranged along the first side S1 of the housing 20, and the fan 10 and the region B arranged along the third side S3 of the housing 20. The region A has a plurality of heat dissipation fins 6 for cooling the electronic components 4a. The plurality of heat dissipation fins 6 formed in the region A are provided parallel to the first side S1 and in the first direction X. Each of the plurality of heat dissipation fins 6 formed in the region A has a path length of a distance LA. The region B has a plurality of heat dissipation fins 6 for cooling the electronic components 4b. The plurality of heat dissipation fins 6 formed in the region B are provided parallel to the third side S3 and in the second direction Y. Each of the plurality of heat dissipation fins 6 formed in the region B has a path length of a distance LB that is longer than the distance LA.

[0024] As shown in Fig. 4, a portion of the fin cover 8 located above the electronic component 4a is provided with a plurality of convex projections 9, and the convex projections 9 on the fin cover 8 are disposed between the plurality of heat dissipation fins 6 disposed above the electronic component 4a. On the other hand, as shown in Fig. 5, a portion of the fin cover 8 located above the electronic component 4b is not provided with a plurality of convex projections 9, and therefore no projections 9 are disposed between the plurality of heat dissipation fins 6 disposed above the electronic component 4b.

[0025] The flow path cross section of the region A will be described with reference to FIG. 6. As described above, the inside (lower side) of the fin cover 8 in the region A has a plurality of protruding parts 9 in a convex shape, and a comb-shaped flow path through which the air, which is a refrigerant, flows is formed. The area of ​​one flow path cross section in the region A is the area obtained by subtracting the area of ​​the protruding parts 9 from the area of ​​the area surrounded by the pair of fins 6, 6, the lower surface of the fin cover 8, and the upper surface of the base surface 1A of the upper housing 1. In one flow path cross section in the region A, the length 9a of the gap between the base of the fin 6 (the upper surface of the upper housing 1 on which the fin 6 is not formed) and the tip of the protruding part 9 is larger than the length 9b of the gap between the side of the fin 6 parallel to the flow path direction and the side of the protruding part 9 (9a>9b). The lengths 9a and 9b of the gap may be equal (9a=9b). In other words, the relationship between the lengths 9a and 9b of the gap may be 9a≧9b. By making 9a>9b, air can be caused to flow more efficiently through the gap between the base of the fin 6 and the tip of the protrusion 9, thereby improving the heat dissipation of the electronic component 4a.

[0026] On the other hand, as shown in FIG. 5, the area of ​​one flow path cross section in region B is the area surrounded by the pair of fins 6, 6, the lower surface of the fin cover 8, and the upper surface of the base surface 1A of the upper housing 1, since no protrusion 9 is provided inside (underside) of the fin cover 8 in region B.

[0027] Therefore, the area of ​​one flow passage cross section in the region A is smaller than the area of ​​one flow passage cross section in the region B by the area of ​​the protrusion 9. This increases the pressure loss in the region A without changing the surface area of ​​the fin 6, and reduces the pressure loss difference between the region A and the region B. This improves the heat dissipation of the second electronic component 4b. In addition, in the region A, the heat dissipation can be improved by actively flowing the cooling air to the base of the fin 6 close to the electronic component 4a, which is the heat source. In other words, in the flow passage between the fins 6 formed on each electronic component 4a, 4b, the inside of the fin cover 8 in the region A (the region of the electronic component 4a) where the flow passage is short is made into a comb-tooth shape by forming a convex protrusion 9, and the pressure loss difference with the region B (the region of the electronic component 4b) where the flow passage is long can be reduced. This prevents the electronic components 4a, 4b from dissipating heat unevenly while efficiently dissipating heat simultaneously.

[0028] Next, the vertical length of the multiple protrusions 9 provided on the fin cover will be described with reference to FIGS.

[0029] 6 shows a first configuration example of a plurality of protrusions 9, in which the length of each of the protrusions 9 is the same. Therefore, in each of the protrusions 9, the length 9a of the gap between the base of the fin 6 (the upper surface of the upper housing 1 where the fins 6 are not formed) and the tip of the protrusion 9 is the same.

[0030] On the other hand, FIG. 7 shows a second configuration example of the multiple protrusions 9, and the multiple protrusions 9 (91, 92, 93) are configured to have different lengths. In FIG. 7, the length of the two protrusions 91 provided on the upper side of the electronic component 4a is the shortest. The length of the protrusions 92 provided on the left and right of the protrusion 91 is longer than the length of the protrusion 91, and the length of the protrusion 93 provided next to the protrusion 92 is longer than the length of the protrusion 92. In other words, the length 9a' of the gap between the base of the fin 6 (the upper surface of the upper housing 1 where the fin 6 is not formed) and the tip of the protrusion 91 is longer than the length 9a of the gap between the base of the fin 6 (the upper surface of the upper housing 1 where the fin 6 is not formed) and the tip of the protrusion 93 (9a'>9a). Therefore, in the region A, the protrusions 9 are longer (the cross-sectional area of ​​the flow path is smaller) in the flow path located away from the position directly above (or above) the electronic component 4a than in the flow path located directly above (or above) the electronic component 4a. This allows cooling air to actively flow through the flow paths between the fins 6 on the electronic components 4a, improving heat dissipation.

[0031] Next, the lengths of the multiple protrusions 9 provided on the fin cover as viewed from above will be described with reference to Figures 8, 9, and 10. Figure 8 is a top view of the fin cover of the electronic control device shown in Figure 1. Figure 9 is a top view showing a modified example of the fin cover of the electronic control device shown in Figure 1. Figure 10 is a cross-sectional view of the electronic control device along line III-III shown in Figure 9, in which the fin cover of Figure 9 is attached.

[0032] As shown in FIG. 8, each of the multiple protrusions 9 provided on the fin cover 8 is provided in the region A with a length of a distance LA in the first direction X in a top view (plan view).

[0033] On the one hand, as shown in FIG. 9, each of the plurality of protrusions 94 provided on the fin cover 8A according to the modified example has a length of a distance L94 shorter than a distance LA in the first direction X in a top view (plan view) (L94 < LA). That is, when viewed from above, it is formed at least in the region where the electronic component 4a is arranged. Further, as shown in FIG. 10, in the region A, the inverted trapezoidal convex shape of the protrusion 94 is formed at least in the flow path directly above the electronic component 4a. By providing the convex shape of the protrusion 94 only above the region where the electronic component 4a is arranged, the cross-sectional area of the flow path above the region where the electronic component 4a is arranged can be reduced, and the flow velocity of the cooling air in the flow path directly above the electronic component 4a can be locally increased. Thereby, the heat dissipation performance can be improved.

[0034] Note that, in FIG. 10, a configuration example in which the convex shape of the protrusion 94 is provided over the entire upper side of the electronic component 4a is shown, but the present invention is not limited thereto. It is sufficient that the convex shape of the protrusion 94 is arranged at least in a part of the upper side of the electronic component 4a. Also with this configuration, the heat dissipation performance can be improved in the same manner as described above.

[0035] Next, the pressure loss simulation will be described with reference to FIGS. 13 - 17. FIG. 13 is a diagram showing the formula for the pressure loss used in the simulation. FIG. 14 is an explanatory diagram of the electronic control device according to the embodiment used in the simulation. FIG. 15 is an explanatory diagram of the electronic control device according to the comparative example used in the simulation. FIG. 16 is a comparative diagram for explaining the simulation results. FIG. 17 is a diagram showing a specific numerical example of the simulation results.

[0036] The pressure loss (ΔP loss ) is the frictional pressure loss generated between the fluid (air) and the flow path wall surface (fin 6) when the air, which is the refrigerant from the fan 10, passes through between the fins 6, and is represented by the formulas 130, 131, and 132 shown in FIG. 13. In the pressure loss simulation, these formulas were used.

[0037] Figure 14 shows electronic control device 100 according to the embodiment used in the simulation, and electronic control device 100 has a configuration in which fin cover 8 having multiple protrusions 9 described in Figure 8 is placed on top of upper housing 1 described in Figure 3. Figure 15 shows electronic control device 100R according to a comparative example used in the simulation, and has a configuration in which fin cover 8R without protrusions 9 is placed on top of upper housing 1 described in Figure 3. The main values ​​used in the simulation are as follows.

[0038] Size of electronic control device 100, 100R: 200mm x 120mm Fan 10 size: 50mm x 50mm Size of area A: 50mm x 63mm (path length LA: 63mm) Size of area B: 50mm x 143mm (path length LB: 143mm) Fin 6 Spacing: 5.0mm Fin 6 thickness: 2.0mm Height of fin 6: 14 mm (for electronic control device 100), 15 mm (for electronic control device 100R) 9a:1.5mm 9b:2.0mm In the simulations of Equation 130, Equation 131, and Equation 132, the pressure loss (ΔP loss ) was calculated.

[0039] FIG. 16 shows a cross-sectional view of region A, a cross-sectional view of region B, and a pressure loss (ΔP loss ) In addition, in Figure 16, the pressure loss ΔP loss is simplified and expressed as ΔP.

[0040] In the electronic control device 100R according to the comparative example in FIG. 16, as can be seen from the cross-sectional views of the regions A and B, the fin cover 8R is configured without the protrusions 9. The simulation results show that the pressure loss in the region A is 5.8 Pa, and the pressure loss in the region B is 13.2 Pa. Therefore, the pressure loss in the region B (13.2 Pa) is about 2.3 times the pressure loss in the region A (5.8 Pa), and the pressure loss difference is relatively large. Therefore, the flow rate of the cooling air in the region A is large, and the flow rate of the cooling air in the region B is small. Therefore, the electronic component 4a in the region A efficiently dissipates heat, but the electronic component 4b in the region B cannot efficiently dissipate heat. In other words, there is a bias in the heat dissipation between the electronic component 4a in the region A and the electronic component 4b in the region B.

[0041] On the other hand, in the electronic control device 100 according to the embodiment of FIG. 16, as can be seen from the cross-sectional view of the region A and the region B, the fin cover 8 in the region A is provided with the protrusions 9, and the fin cover 8 in the region B is not provided with the protrusions 9. The result of the simulation is that the pressure loss in the region A is 15.3 Pa, and the pressure loss in the region B is 13.2 Pa. Therefore, the pressure loss in the region B (13.2 Pa) is about 0.9 times the pressure loss in the region A (15.3 Pa), and the pressure loss difference is relatively small. Therefore, the flow rate of the cooling air in the region A is reduced compared to the flow rate of the cooling air in the region A of the comparative example, but the flow rate of the cooling air in the region B is greater than the flow rate of the cooling air in the region B of the comparative example. Therefore, both of the electronic components 4a and 4b in the region A are efficiently dissipated heat without any bias in heat dissipation. That is, the electronic control device 100 according to the embodiment is configured to be able to simultaneously dissipate heat from a plurality of electronic components 4a, 4b using one fan 10 by controlling the pressure loss in the flow paths between the fins 9.

[0042] (Modification) Next, a modified example will be described.

[0043] (Variation 1) FIG. 11 is a top view of the electronic control device according to the first modification.

[0044] The shape of the electronic control device 100 in top view is not limited to a rectangular shape such as a rectangle as shown in Figs. 1 to 3. As shown in Fig. 11, the shape of the electronic control device 100A in top view may be a rectangular shape such as a square. That is, the distance LA in the first flow path direction X and the distance LY in the second flow path direction Y may be the same length (LA = LB). In this case, the electronic component 4a has a low heat value, and the electronic component 4b has a high heat value compared to the heat value of the electronic component 4a. Although not shown, a plurality of protrusions (9 or 94) are provided in the portion corresponding to the region A of the fin cover 8, as described in the embodiment.

[0045] In an electronic control device 100A provided with an electronic component 4a that generates a low amount of heat and an electronic component 4b that generates a high amount of heat, a single cooling fan 10 can simultaneously dissipate heat from the electronic components 4a and 4b while preventing uneven heat dissipation.

[0046] (Variation 2) FIG. 12 is a top view of the electronic control device according to the second modification.

[0047] The number of electronic components mounted on the electronic control device 100 is not limited to two, the electronic components 4a and 4b. As shown in the electronic control device 100B of FIG. 12, three electronic components 4a, 4b, and 4c may be provided. The difference between FIG. 12 and FIG. 3 is that in the electronic control device 100B of FIG. 12, a third electronic component 4c is mounted in the area below the cooling fan 10. In this case, the heat generation amount of the third electronic component 4c is larger than the heat generation amount of the electronic components 4a and 4b. The area below the cooling fan 10 is an area with good heat dissipation, so it is the most suitable place to mount the third electronic component 4c, which generates a large amount of heat. The three electronic components 4a, 4b, and 4c can be simultaneously dissipated with one cooling fan 10 while preventing uneven heat dissipation.

[0048] (Variation 3) In the above description, the tips of the fins 6 formed on the upper housing 1 and the fin cover 8 are depicted as being spaced apart, but this is not limited thereto. The tips of the fins 6 formed on the upper housing 1 and the fin cover 8 may be configured to be in contact with each other at at least one location or over the entire surface. With this configuration, as a heat dissipation path for the electronic components 4a, 4b, a second heat dissipation path by the fins 6-fin cover 8 can be added to the first heat dissipation path by the cooling air. This allows the heat of the electronic components 4a, 4b to be efficiently dissipated by the first and second heat dissipation paths.

[0049] (Variation 4) In the above description, the coolant is air (air-cooled), but the coolant is not limited to this. The coolant may be water (water-cooled).

[0050] The invention made by the inventor has been specifically described above based on examples. However, it goes without saying that the present invention is not limited to the above-mentioned embodiments and examples, and various modifications are possible. [Explanation of symbols]

[0051] 100: Electronic control device A: Area A B: Area B 1: Upper case (cooling mechanism) 1A: Base surface of the upper housing 2: Lower housing 3: Circuit board 4a: First electronic component 4b: Second electronic component 4c: The third electronic component 5: Heat transfer material 6: Heat dissipation fin 7: Boss 8: Fin cover 9: Convex protrusion of the fin cover 9a: Length of the gap between the tip of the convex shape and the base of the heat sink fin 9b: Length of the gap between the convex side and the fin side 10: Fan 20: Cabinet

Claims

1. A housing having fins; a cooling mechanism having a fin cover for forming a flow path of a coolant on the fin; a coolant circulation device for circulating the coolant through the flow path; On the circuit board in the housing, a first electronic component and a second electronic component are in contact with a base surface of the housing via a heat transfer member, the housing includes an area A having the first electronic component and an area B having the second electronic component, The flow paths and the fins in the region A are provided along a first direction, The flow paths and the fins in the region B are provided along a second direction intersecting the first direction, The region A and the refrigerant circulation device are arranged along the first direction, The region B and the refrigerant circulation device are arranged along the second direction, The flow path is longer in the region B than in the region A, The inner surface of the fin cover in the region A has a convex protrusion, and the flow path is formed in a comb shape, The electronic control device, wherein the inner side of the fin cover in the region B does not have a convex protrusion.

2. In claim 1, An electronic control device, wherein in the flow path cross section of the region A, the gap between the base of the fin and the tip of the convex-shaped protrusion is larger than the gap between the side of the fin parallel to the direction of the flow path and the side of the convex-shaped protrusion.

3. In claim 2, an electronic control device, wherein in the convex protrusion of the fin cover in the region A, a flow path arranged on the upper side of the first electronic component between the base of the fin and the tip of the convex protrusion is larger than a flow path arranged at a position away from the upper side of the first electronic component.

4. In claim 3, The convex projections of the fin cover formed in each flow passage in the region A are An electronic control device formed in a region in which at least the first electronic component is disposed, as viewed from above.

5. A housing having fins; a cooling mechanism having a fin cover for forming a flow path of a coolant on the fin; a coolant circulation device for circulating the coolant through the flow path; On the circuit board in the housing, a first electronic component and a second electronic component are in contact with a base surface of the housing via a heat transfer member; the housing includes an area A having the first electronic component and an area B having the second electronic component, The flow paths and the fins in the region A are provided along a first direction, The flow paths and the fins in the region B are provided along a second direction intersecting the first direction, The region A and the refrigerant circulation device are arranged along the first direction, The region B and the refrigerant circulation device are arranged along the second direction, The inner surface of the fin cover in the region A has a convex protrusion, and the flow path is formed in a comb shape, The inner side of the fin cover in the region B does not have a convex protrusion, The length of the flow path in the housing is equal to that of the region A and the region B, An electronic control device, wherein a heat generation amount of the second electronic component is greater than a heat generation amount of the first electronic component.

6. In claim 1, The electronic control device, wherein the fin cover is in contact with the tip of the fin of the housing at at least one point.

7. In claim 1, The electronic control device, wherein the housing has a forced air-cooling structure equipped with a cooling fan as the refrigerant circulation device.

8. In claim 7, the housing has a third electronic component immediately below the fan, An electronic control device, wherein a heat generation amount of the third electronic component is greater than a heat generation amount of the first electronic component and a heat generation amount of the second electronic component.

9. In claim 1, The electronic control device, wherein the fin cover is made of a metal or resin material.

10. A first electronic component; A second electronic component; an upper housing having a base surface and a plurality of fins provided on an upper side of the base surface; a fin cover provided to cover an upper side of the plurality of fins of the upper housing; a first region having a plurality of first flow paths for flowing a coolant for cooling the first electronic component; a second region having a plurality of second flow paths for flowing a coolant for cooling the second electronic component; a coolant circulation device for circulating the coolant through the first flow path and the second flow path, The first flow paths and the fins in the first region are provided along a first direction, the second flow paths and the fins in the second region are provided along a second direction intersecting the first direction, The first region and the refrigerant circulation device are arranged along the first direction, The second region and the refrigerant circulation device are arranged along the second direction, the fin cover has a lower surface and a plurality of protrusions provided on the lower surface so as to correspond to an upper area of ​​the first electronic component, Each of the cross sections of the plurality of first flow paths is formed by a pair of the fins, the base surface, the lower surface of the fin cover, and one of the plurality of protrusions, An electronic control device, wherein each of the cross sections of the plurality of second flow paths is defined by a pair of the fins, the base surface, and the lower surface of the fin cover.

11. In claim 10, The path lengths of the first flow paths are: Shorter than the path length of the second flow paths; or the path length of the second flow paths being equal to the path length of the second flow paths.

12. In claim 10, The length of the plurality of protrusions is The length is the same as the length of the fins that configure the first flow path, or An electronic control device having a length shorter than the length of the plurality of fins that define the first flow path.

13. In claim 10, An electronic control device, wherein in each flow path cross-section of the first region, a gap between the base of the fin and the tip of the protrusion is larger than a gap between a side of the fin and a side of the protrusion parallel to the flow path direction of the refrigerant.

14. In claim 10, an electronic control device, wherein, in the multiple protrusions of the fin cover, a flow path of the multiple first flow paths that is arranged above the first electronic component between the base of the fin and the tip of the protrusion is larger than a flow path of the multiple first flow paths that is arranged away from the upper side of the first electronic component.

15. In claim 10, The coolant circulation device has a fan for flowing air as the coolant through the plurality of first flow paths and the plurality of second flow paths.

16. In claim 15, The heat generation amount of the first electronic component is When a path length of the plurality of first flow paths is shorter than a path length of the plurality of second flow paths, the heat generation amount is set to be equal to that of the second electronic component, When the path length of the first flow paths is the same as the path length of the second flow paths, the amount of heat generated is less than the amount of heat generated by the second electronic component.

17. In claim 15, the housing has a third electronic component in a region below the fan, An electronic control device, wherein a heat generation amount of the third electronic component is greater than a heat generation amount of the first electronic component and a heat generation amount of the second electronic component.

18. In claim 10, The fin cover contacts the tips of the fins at at least one point.

19. In claim 10, The electronic control device, wherein the fin cover is made of a metal or resin material.

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