Electronic Controls

Abstract

The present invention provides an electronic control device, comprising: a first electronic component with a first calorific value; a second electronic component with a second calorific value smaller than the first calorific value; a circuit board on which the first electronic component and the second electronic component are mounted; and a housing for accommodating the first electronic component, the second electronic component and the circuit board, the electronic control device comprising a heat dissipation housing having a heat dissipation structure for dissipating heat from the first electronic component and the second electronic component, the heat dissipation structure comprising a heat dissipation block thermally coupled to the first electronic component, and a plurality of plate-shaped heat dissipation fins extending outward from the outer periphery of the heat dissipation block.

Description

Technical Field

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

[0002] Semiconductor elements used in electronic control devices for vehicles and the like have a reduced housing volume due to miniaturization, but have an increased heat generation due to improved performance. Therefore, there is a demand for further improvement in the heat dissipation performance of electronic control devices.

[0003] As a heat dissipation structure for improving the heat dissipation of semiconductor elements, a semiconductor assembly is known in which a circuit board on which a semiconductor element is mounted and a heat dissipation substrate provided with a heat dissipation block and a plurality of needle-shaped fins arranged on the periphery of the heat dissipation block are joined together using solder or the like (for example, refer to Patent Document 1).

[0004] Prior art literature

[0005] Patent Literature

[0006] Patent Document 1: Japanese Patent Application Publication No. 2016-219560 Summary of the invention

[0007] Problems to be solved by the invention

[0008] The heat dissipation structure described in the above-mentioned Patent Document 1 is a structure of a semiconductor component, and the area of ​​the heat dissipation substrate is small. Therefore, the heat dissipation performance is not sufficient. In addition, there is no description or suggestion about the structure of heat dissipation from the housing that accommodates the semiconductor component.

[0009] Technical solutions to solve problems

[0010] According to one embodiment of the present invention, an electronic control device includes: a first electronic component with a first calorific value; a second electronic component with a second calorific value smaller than the first calorific value; a circuit board on which the first electronic component and the second electronic component are mounted; and a housing for accommodating the first electronic component, the second electronic component and the circuit board, which includes a heat dissipation housing formed with a heat dissipation structure for dissipating heat from the first electronic component and the second electronic component, the heat dissipation structure including a heat dissipation block thermally coupled to the first electronic component, and a plurality of plate-shaped heat dissipation fins extending outward from the outer periphery of the heat dissipation block.

[0011] Effects of the Invention

[0012] According to the present invention, it is possible to provide an electronic control device having improved heat dissipation performance. BRIEF DESCRIPTION OF THE DRAWINGS

[0013] Figure 1 It is an external perspective view of a first embodiment of an electronic control device according to the present invention.

[0014] Figure 2 yes Figure 1 A cross-sectional view of the electronic control device taken along line II-II shown.

[0015] Figure 3 yes Figure 1 A top view of the electronic control unit is shown.

[0016] Figure 4 Yes means Figure 3 A plan view of the layout inside the housing of the electronic control device is shown.

[0017] Figure 5 It is a top view of an electronic control device of a comparative example.

[0018] Figure 6 It is a graph showing the junction temperature of Example 1 of the present invention and Comparative Example 1.

[0019] Figure 7 It is a graph showing the surface temperature of the heat dissipation casings of Example 1 of the present invention and Comparative Example 1.

[0020] Figure 8 is a graph showing the junction temperature corresponding to the installation posture of Example 1 of the present invention and Comparative Example 1, Figure 8 (a) to (c) are external perspective views showing the installation postures of the electronic control device, respectively. Figure 8 (d) is a graph showing the junction temperatures of Example 1 and Comparative Example 1 corresponding to each installation posture.

[0021] Fig. 9 It is a plan view of an electronic control device according to a second embodiment of the present invention. DETAILED DESCRIPTION

[0022] Hereinafter, embodiments of the present invention will be described with reference to the accompanying drawings. The following description and accompanying drawings are examples for illustrating the present invention, and are appropriately omitted and simplified for clarity of the description. The present invention can also be implemented in various other ways. Unless otherwise specified, each constituent element can be single or multiple.

[0023] Regarding the positions, sizes, shapes, ranges, etc. of the components shown in the drawings, there are cases where the actual positions, sizes, shapes, ranges, etc. are not shown in order to facilitate the understanding of the invention. Therefore, the present invention is not limited to the positions, sizes, shapes, ranges, etc. disclosed in the drawings.

[0024] - First Embodiment -

[0025] Below, reference Figures 1 to 8 , describing the first embodiment of the present invention.

[0026] Figure 1is a perspective view of the appearance of the electronic control device of the present invention, Figure 2 yes Figure 1 A cross-sectional view of the electronic control device taken along line II-II shown.

[0027] The electronic control device 100 has a housing composed of a heat dissipation housing 1 and a lower housing 2. The heat dissipation housing 1 and the lower housing 2 are fixed by fastening members such as bolts (not shown). On the front surface of the housing, one or more connectors 8 and a plurality of Ethernet (registered trademark) terminals 9 are arranged as a connection portion for electrical connection with an external device. The connector 8 includes a connector for power supply. The inside of the housing accommodates a circuit board 3, electronic components 4a to 4d including semiconductor elements such as a microcontroller (see Figure 4 ) and a heat conductive material 5. In addition, the electronic components 4a to 4d are sometimes described with reference numeral 4 representing them.

[0028] In the following description, the X direction, the Y direction, and the Z direction are as shown in the drawings.

[0029] The heat dissipation housing 1 is formed of a metal material with excellent thermal conductivity such as aluminum (e.g., ADC12). The heat dissipation housing 1 can also be formed of a metal plate such as iron or a non-metal material such as a resin material to achieve low cost and light weight. The heat dissipation housing 1 has a rectangular shape in a plan view, such as Figure 2 As shown in the figure, the peripheral side is bent downward (toward the circuit board 3 side) by approximately 90 degrees to form a box shape with an open opening. Boss portions 10 protruding toward the circuit board 3 side are provided near the four corners and the center of the heat dissipation housing 1. The circuit board 3 is fixed to the end face of the boss portion 10 by bolts 21.

[0030] like Figure 1 As shown, the front surface side (the side in the Y direction) of the top surface (the side in the Z direction) of the heat dissipating housing 1 is a flat surface.

[0031] The heat dissipation housing 1 comprises a front portion 11 and a main body 12 (see Figure 2 ), a heat sink 13 and a plurality of plate-shaped heat sink fins 14. The heat sink 13 and the heat sink fins 14 are the main elements of the heat dissipation structure. The front portion 11, the main body 12, the heat sink 13, the heat sink fins 14, and the boss portion 10 are integrally formed on the heat dissipation housing 1 by die casting or the like. However, the heat sink fins 14, the heat sink 13, and the boss 10 may be manufactured as components separate from the front portion 11 and the main body 12, and may be mounted on the front portion 11 and the main body 12 by fastening components or welding or the like.

[0032] A hole or cutout (not shown) for inserting the connector 8 and the Ethernet terminal 9 is formed on the side wall on the front surface of the heat dissipation housing 1, and the connector 8 and the Ethernet terminal 9 are connected to the wiring pattern (not shown) formed on the circuit board 3 through the hole or cutout. The power and control signals are sent and received between the outside and the electronic control device 100 via the connector 8 and the Ethernet terminal 9.

[0033] The lower housing 2 is formed of a metal material with excellent thermal conductivity such as aluminum, similarly to the heat dissipation housing 1. The lower housing 2 can also be formed of a metal plate such as iron or a non-metal material such as a resin material, similarly to the heat dissipation housing 1, to achieve low cost and light weight. A hole or cutout for inserting the connector 8 or the Ethernet terminal 9 can be formed in the lower housing 2. Alternatively, a cutout that becomes one hole when the two components are assembled can be formed in the heat dissipation housing 1 and the lower housing, respectively.

[0034] The front portion 11 of the heat dissipation housing 1 includes a covering portion covering the Ethernet terminal 9 and a covering portion covering the connector 8. The main body 12 is a plate-shaped member that covers the circuit board 3 and the heat generating component 4 housed inside the housing, and connects a plurality of heat dissipation fins 14 to the heat dissipation block 13. The boundary portion of the front portion 11 with the main body 12 is an inclined surface 11a that descends downward (-Z direction) from the front portion 11, and the main body 12 is arranged at a position lower than the front portion 11 (position on the -Z side). Each heat dissipation fin 14 is connected to the main body 12 at the lower end. In addition, the heat dissipation block 13 has an external protrusion 13b that protrudes upward (Z direction) of the main body 12, and an internal protrusion 13a that protrudes downward (-Z direction) of the main body 12, in other words, to the inside of the housing. The internal protrusion 13a is a convex portion that protrudes from the -Z direction side of the main body 12 side facing the circuit board 3 side, and its side circumference is formed as an inclined surface with a shape in which the front end of the internal protrusion 13a is tapered in the -Z direction. That is, the XZ cross section and the YZ cross section of the internal raised portion 13 a have a substantially trapezoidal shape having a wider lower side portion on the main body portion 12 side.

[0035] like Figure 2 As shown in FIG. 1 , an inclined surface 11a descending toward the main body 12 is provided on the front portion 11 of the heat dissipation housing 1, and the height (Z direction) of each heat dissipation fin 14 from the main body 12 is substantially the same as the height (Z direction) of the external protrusion 13b of the heat dissipation block 13 from the main body 12. That is, the top surface of each heat dissipation fin 14 in the Z direction and the top surface of the heat dissipation block 13 in the Z direction are substantially on the same plane as the top surface of the front portion 11 of the heat dissipation housing 1. In this way, by making the top surface of each heat dissipation fin 14 in the Z direction and the top surface of the heat dissipation block 13 in the same plane as the top surface of the front portion 11 of the heat dissipation housing 1, which has the highest height, the height of the electronic control device 100 is reduced.

[0036] Figure 3 yes Figure 1 A top view of the electronic control unit is shown.

[0037] The heat dissipation housing 1 has a thin rectangular shape whose length in the X direction is greater than its length in the Y direction, and has a peripheral side portion consisting of a pair of side portions (length direction sides) 15a, 15b extending in the X direction and a pair of side portions (width direction sides) 15c, 15d extending in the Y direction.

[0038] like Figure 2 and Figure 3 As shown, the heat sink 13 is a thin component having a rectangular shape of a square or a rectangle in a plan view, and has a pair of sides 16a, 16b extending in the X direction and a pair of sides 16c, 16d extending in the Y direction. The heat sink 13 is arranged slightly closer to the -X side, that is, the side 15c, than the central part in the longitudinal direction, that is, the X direction, of the heat sink housing 1. In addition, the heat sink 13 is arranged in the Y direction at the approximately central part between the inclined surface 11a of the front surface 11 of the heat sink housing 1 and the side 15a.

[0039] As described later, the heat dissipation block 13 is mainly intended to dissipate heat from electronic components that generate large amounts of heat, and its size in plan view is preferably determined in accordance with the size in plan view of the electronic components to be dissipated.

[0040] On each side 16a to 16d of the heat sink 13, a plurality of heat sink fins 14 are respectively provided extending from each side in four directions. In other words, the plurality of heat sink fins connected to the side 16c of the heat sink 13 extend parallel to the -X direction and are connected to the side 15c of the heat sink housing 1. The plurality of heat sink fins 14 connected to the side 16d of the heat sink 13 extend parallel to the X direction and are connected to the side 15d of the heat sink housing 1. The plurality of heat sink fins 14 connected to the side 16a of the heat sink 13 extend parallel to the -Y direction and are bent 90° toward the side 15c or the side 15d at different positions in the Y direction. That is, half of the plurality of heat sink fins 14 connected to the side 16a of the heat sink 13, which are located on the side close to the side 16c of the heat sink 13, are bent 90° toward the side 15c, and then extend parallel to the -X direction and are connected to the side 15c of the heat sink housing 1. In addition, half of the plurality of heat dissipation fins 14 connected to the side 16a of the heat dissipation block 13 located near the side 16d of the heat dissipation block 13 are bent 90 degrees toward the side 15d, and then extend parallel to the X direction and connected to the side 15d of the heat dissipation case 1.

[0041] The plurality of heat dissipation fins 14 connected to the side 16b of the heat dissipation block 13 extend in parallel along the Y direction, and are bent 90° toward the side 15c or the side 15d at different positions in the Y direction. That is, half of the plurality of heat dissipation fins 14 connected to the side 16b of the heat dissipation block 13, which are located on the side close to the side 16c of the heat dissipation block 13, are bent 90° toward the side 15c, and then extend in parallel along the -X direction and are connected to the side 15c of the heat dissipation housing 1. In addition, half of the plurality of heat dissipation fins 14 connected to the side 16b of the heat dissipation block 13, which are located on the side close to the side 16d of the heat dissipation block 13, are bent 90° toward the side 15d, and then extend in parallel along the X direction and are connected to the extension 11b of the front portion 11.

[0042] According to the above description and the accompanying drawings, the heat sink 13 of the heat dissipation housing 1 is arranged at a position closer to the side portion 15c extending in the width direction, i.e., the Y direction, than the central portion in the length direction, i.e., the X direction, of the heat dissipation housing 1. The entire length of a portion of the plate-shaped heat dissipation fins 14 extends in the length direction, i.e., the X direction, of the heat dissipation housing 1. In addition, the remaining portion of the plate-shaped heat dissipation fins 14 has a portion extending in parallel along the width direction of the heat dissipation housing 1, and a portion extending in parallel along the length direction. Moreover, the length of the portion of the remaining portion of the plate-shaped heat dissipation fins 14 extending in parallel along the length direction is longer than the length of the portion extending in parallel along the width direction. That is, the length of the portion of the plate-shaped heat dissipation fins 14 connected to the four sides of the heat dissipation housing 1 extending in the length direction of the heat dissipation housing 1 is longer than the length of the portion extending in the width direction of the heat dissipation housing 1.

[0043] Figure 4 Yes means Figure 3 A plan view of the layout inside the housing of the electronic control device is shown.

[0044] like Figure 2 and Figure 4 As shown, electronic components 4 a to 4 d are mounted on the circuit board 3 .

[0045] The electronic component 4a generates the largest amount of heat among the electronic components 4a to 4d mounted on the circuit board 3. The electronic component 4b generates the second largest amount of heat after the electronic component 4a. The electronic components 4c and 4d generate less heat than the electronic component 4b.

[0046] For the mounting structure of the electronic component 4a, refer to Figure 2 Provide explanation.

[0047] The electronic component 4a is heat-conductively bonded, i.e., thermally coupled, to a connection pad (not shown) formed on the circuit board 3 by a conductive adhesive material 17 such as solder. The circuit board 3 is formed of an organic material such as epoxy resin, for example. The circuit board 3 is preferably made of FR4 material. The circuit board 3 can be a single-layer circuit board or a multi-layer circuit board. In addition, although not shown, a connection portion and a wiring pattern for connecting the connector 8 and the Ethernet terminal 9 are provided on the circuit board 3.

[0048] The heat conducting material 5 ( Figure 2 The area of ​​the bottom surface (-Z direction) of the internal raised portion 13a facing the electronic component 4a (length in the X direction×length in the Y direction) is the same as or larger than the area of ​​the heat generating surface of the electronic component 4a.

[0049] The heat conducting material 5 may be a grease, a jelly, a sheet or other material. Generally, a grease-like heat conducting material is used, such as a thermosetting resin with adhesiveness and a semi-hardened resin with low elasticity. The heat conducting material 5 contains a filler with good heat conductivity formed of metal, carbon, ceramic or the like. The heat conducting material 5 is preferably a semi-hardened resin such as a silicone resin containing a ceramic filler and having a deformable flexibility to the deformation and vibration caused by heat of the circuit board 3 and the tolerance during manufacturing.

[0050] The heat generated by the electronic component 4a is conducted to the heat sink 13 of the heat dissipation housing 1 formed of a material with good thermal conductivity via the heat conductive material 5. The heat conducted to the heat sink 13 is dissipated to the outside from the top surface of the heat sink 13, that is, the top surface of the external raised portion 13b in the +Z direction, and is conducted to each plate-shaped heat dissipation fin 14. The area of ​​the bottom surface (-Z direction) of the heat sink 13, in other words, the area of ​​the surface thermally coupled with the electronic component 4a is larger than the area of ​​the heat dissipation surface of the electronic component 4a. In addition, the height of the heat sink 13 in the Z direction including the internal raised portion 13a is larger than the height of the heat dissipation fin 14.

[0051] Since the Z-direction height and XY dimensions of the heat sink 13 are set in this way, the heat capacity of the heat sink 13 can be set relatively large. Therefore, the heat sink 13 can absorb the heat generated by the electronic component 4a relatively quickly, and can withstand the temporary temperature rise (transition heat) of the heat generating component 4. Since the larger the heat transfer area, the lower the thermal resistance and the easier it is to transfer heat, it is effective to improve the heat dissipation by using a heat sink 13 with a large heat capacity. In addition, the heat sink fins 14 extend parallel to each side 16a to 16d of the heat sink 13 mainly along the length direction of the heat dissipation housing 1. Thus, the full length of the plurality of heat sink fins 14, that is, the full length of the heat conduction path formed by the heat sink fins 14, can be set to be large, so the heat dissipation area is large. Furthermore, most of the ends of the heat sink fins 14 in the X direction are connected to the side portions 15c and 15d of the heat sink housing 1, and a part of the ends are connected to the extension 11b. Thus, the heat dissipation achieved by the heat sink 13 and the heat sink fins 14 can be improved.

[0052] return Figure 4 The electronic components 4a, 4c, and 4d mounted on the circuit board 3 are arranged in the first region R in the X direction in the XY plane. H In the embodiment, the electronic component 4b is arranged in the second region R in the X direction in the XY plane. L middle.

[0053] The electronic component 4a is, for example, a circuit for calculation and processing such as an FPGA (Field-Programmable Gate Array) or an ASIC that generates a large amount of heat, and the electronic component 4b is a circuit that generates less heat than the electronic component 4a, such as a microcontroller, etc. In addition, the electronic component 4c is a circuit that generates the same amount of heat as or less than the electronic component 4b, such as a microcontroller, or an active element such as a resistor or a capacitor, and the electronic component 4d is a circuit that generates the same amount of heat as or less than the electronic component 4c, such as a memory chip, or an active element such as a resistor or a capacitor.

[0054] The electronic components 4c and 4d are arranged around the electronic component 4a, and the first region R where the electronic components 4a, 4c and 4d are mounted is H The second region R where the electronic components 4b are arranged L is related to the first region R H The low heat generation area has a smaller heat generation than the electronic component 4a. The electronic component 4b is arranged at a distance from the electronic component 4a in the length direction. The distance between the electronic component 4b and the electronic component 4a is greater than the distance between the electronic component 4c or the electronic component 4d and the electronic component 4a.

[0055] First Region R H With the second region R L The boundary line R SHowever, in a layout where another electronic component 4e (not shown) having a heat generation equal to or greater than that of the electronic component 4b is arranged in the region between the electronic component 4a and the electronic component 4b, the boundary line R S It can also be set in any of the areas between the electronic component 4a and the other electronic component 4e, or between the electronic component 4b and the other electronic component 4e. H Defined as the second region R L Compared with the area with higher heat generation, for the first area R H and the second region R L and the boundary line R S The position of the device should be appropriately judged based on this definition.

[0056] The Ethernet terminal 9 is arranged in the first area R H The end portion in the Y direction (the side of the side portion 15b of the heat dissipation housing 1) is located in the first region R H In addition, the connector 8 including the power supply connector is arranged in the second region R. L The end portion in the Y direction (the side of the side portion 15b of the heat dissipation housing 1) is located in the second region R L The connector 8 including the power connector generates more heat than the Ethernet terminal 9. In this embodiment, the Ethernet terminal 9 is arranged in the first region R where the heat generation is large. H The connector 8 is arranged in the second region R, which is a low heat generation region. L Thus, it is possible to realize the H The heat generated and the heat dissipated, and the second area R L The balance between heat generation and heat dissipation is achieved, thereby improving the overall heat dissipation of the electronic control device 100.

[0057] As described above, since the heat dissipation block 13 has a large heat capacity, the heat generated by the electronic component 4 a is immediately absorbed by the heat dissipation block 13 . The heat absorbed by the heat dissipation block 13 is dissipated from the heat dissipation block 13 to the outside and conducted to each plate-shaped heat dissipation fin 14 .

[0058] Compared with the prior art that ensures heat dissipation performance by setting up fins around the heat sink, the overall heat dissipation performance is improved by making many improvements such as setting fins on the side of the heat sink and configuring the heat sink in a manner that the fins extend in the length direction of the heat sink housing.

[0059] As described above, the heat sink 13 is disposed at a position slightly closer to the side portion 15c than the center portion in the X direction of the heat sink housing 1. In other words, the distance between the side 16d of the heat sink 13 and the side portion 15d of the heat sink housing 1 is greater than the distance between the side 16c of the heat sink 13 and the side portion 15c of the heat sink housing 1. That is, the distance from the side 16d of the heat sink 13 to the side portion 15c of the heat sink housing 1 is greater than the distance from the side 16c of the heat sink 13 to the side portion 15c of the heat sink housing 1. L The heat dissipation fins 14 connected to the side portion 15d of the heat dissipation housing 1 are relatively long. The heat generated by the electronic component 4a and conducted to the heat dissipation block 13 is conducted in the plurality of plate-shaped heat dissipation fins 14 themselves, and while being radiated to the outside, the heat is dissipated from the first region R where the heat generation is large. H Passing through the second region R with low heat generation L The heat is transported to the side portion 15 d of the heat dissipating housing 1 .

[0060] In a natural air cooling environment, the heat transfer of the cooling medium has little effect on the heat dissipation, and the heat dissipation is improved due to the reduction of the temperature gradient of the object caused by heat conduction and radiation. Therefore, the heat generated by the electronic component 4a is effectively conducted and dissipated to the entire heat dissipation housing 1, and the heat dissipation is improved.

[0061] [Example 1]

[0062] The following parts were used to make a Figure 1 and Figure 3 The appearance shown, with Figure 2 The cross-sectional structure and Figure 4 The electronic control device 100 has the layout of the interior of the casing shown in FIG. The circuit board 3 is fixed to the bosses 10 provided at the four corners and the center of the heat dissipation housing 1 by bolts 21 .

[0063] The electronic component 4a, which generates the most heat, is a BGA (Ball Grid Array) type semiconductor device of 31 mm×31 mm×3.1 mm (thickness), and is mounted on the circuit board 3 by soldering. Figure 4 The arrangement shown is mounted on a circuit board 3 .

[0064] The circuit board 3 is formed of FR4 material having a size of 187 mm x 102.5 mm x 1.6 mm (thickness). The circuit board 3 is an 8-layer circuit board, and the thermal conductivity is 69 W / mK in the in-plane direction and 0.45 W / mK in the perpendicular direction.

[0065] The heat dissipation housing 1 and the lower housing 2 are formed using ADC12 having a thermal conductivity of 96 W / mK and an emissivity of 0.8.

[0066] The thermal conductive material 5 is formed by using a low elasticity heat dissipation material containing a thermal conductive filler in a silicone resin with a thermal conductivity of 2 W / mK. The thermal conductive material 5 is arranged on the upper part of all the electronic components 4a to 4d. The size of the thermal conductive material 5 arranged on the upper part of each electronic component 4a to 4d is the same as the size of the electronic component 4a to 4d on which the thermal conductive material 5 is arranged. In addition, the thermal conductive material 5 is made to have the same thickness of 1.9 mm. On all the electronic components 4a to 4d of the heat dissipation housing 1, only the internal protrusion 13a of the heat dissipation block 13 is formed, and the upper part of the thermal conductive material 5 arranged on all the electronic components 4a to 4d is connected to the internal protrusion 13a of the heat dissipation block 13. The thickness of the internal protrusion 13a is made different according to the thickness of each electronic component 4a to 4d, so that the main body 12 of the heat dissipation housing 1 is flat in the horizontal direction.

[0067] Figure 5 It is a top view of an electronic control device of a comparative example.

[0068] As Comparative Example 1, a Figure 5 The electronic control device 101 is shown in the heat dissipation housing 1R.

[0069] The heat dissipation housing 1R of Comparative Example 1 has no heat dissipation block. In addition, the plate-shaped heat dissipation fins 14r of the heat dissipation housing 1R of Comparative Example 1 all extend in the width direction of the heat dissipation housing 1R, i.e., the Y direction, and have no portion extending in the length direction of the heat dissipation housing 1R, i.e., the X direction.

[0070] That is, all the plate-shaped heat dissipating fins 14r of Comparative Example 1 extend linearly in the Y direction from the side portion 15a of the heat dissipating housing 1R and are connected to the side portion 15b or the front portion 11 opposite to the side portion 15a.

[0071] The other structures of Comparative Example 1 are the same as those of Example 1.

[0072] Figure 6 It is a graph showing the junction temperature of Example 1 of the present invention and Comparative Example 1.

[0073] Figure 6 , the junction temperature of the electronic component 4a with the largest heat generation is shown in the electronic control device 100 of the first embodiment and the electronic control device 101 of the first comparative example. The junction temperature is Figure 2 The temperature of a substantially central portion JT of one side surface on the outer peripheral side of the electronic component 4a is shown.

[0074] Figure 6 The junction temperature shown is the temperature when the total heat generation of the electronic control devices 100 and 101 is 20W (including the heat generation of the electronic component 4a, 9W), in a windless environment and an ambient temperature of 85°C. Figure 6As shown, the junction temperature of the electronic component 4a of Example 1 is lower than the junction temperature of the heat generating component 4a of Comparative Example 1. Therefore, it is confirmed that the electronic control device 100 of Example 1 has a greater heat dissipation effect than the electronic control device 101 of Comparative Example 1.

[0075] Figure 7 It is a graph showing the surface temperature of the heat dissipation casings of Example 1 of the present invention and Comparative Example 1.

[0076] exist Figure 7 Surface temperatures of the heat dissipating housing 1 of the electronic control device 100 of Example 1 and the heat dissipating housing 1R of the electronic control device 101 of Comparative Example 1 are shown in FIG. Figure 7 The horizontal axis, i.e. the heat dissipation housing distance, refers to Figure 3 and Figure 5 The distance from the side portion 15c in the -X direction of the heat dissipation housing 1, 1R. Figure 7 The vertical axis, that is, the heat dissipation housing surface temperature, refers to the measured temperature of the substantially central portion of the heat dissipation housing 1 , 1R in the Y direction.

[0077] The heat sink block 13 of the first embodiment is arranged at a position about 30 to 80 mm away from the heat sink housing.

[0078] like Figure 7 As shown, the surface temperature of the heat dissipation housing of Example 1 is in the entire area R where the heat dissipation block 13 is located. B The surface temperature of the heat dissipating case 1 is lower than that of the comparative example 1. This is considered to be because the heat absorbed from the electronic component 4 a by the heat dissipating block 13 is transferred to the heat dissipating fins 14 and transported to the peripheral edge of the heat dissipating case 1 .

[0079] In addition, according to Figure 7 , when the distance from the heat dissipation housing exceeds 100 mm, the surface temperature of the heat dissipation housing 1 of Example 1 becomes higher than the surface temperature of the heat dissipation housing 1R of Comparative Example 1. That is, the difference between the highest temperature and the lowest temperature of the surface temperature of the heat dissipation housing 1 of Example 1 is smaller than the difference between the highest temperature and the lowest temperature of the surface temperature of the heat dissipation housing 1R of Comparative Example 1. This can be explained as follows.

[0080] In the heat dissipation housing 1 of the first embodiment, the heat absorbed by the heat dissipation block 13 passes through the heat dissipation fins 14 and passes through the second region R where the heat generation is small. L During the period when the heat is conducted upward to the side portion 15d in the X direction of the heat dissipating housing 1, the heat is sufficiently dissipated from the heat dissipating fins 14. Thus, it is confirmed that the electronic control device 100 of Example 1 has a better heat dissipation effect than the electronic control device 101 of Comparative Example 1, and the maximum temperature of the heat dissipating housing 1 is lower than the maximum temperature of the heat dissipating housing 1R of Comparative Example 1.

[0081] Figure 8 is a graph showing the junction temperatures corresponding to the installation postures of Example 1 of the present invention and Comparative Example 1, Figure 8 (a) to (c) are external perspective views showing the installation postures of the electronic control device, respectively. Figure 8 (d) is a graph showing the junction temperatures of Example 1 and Comparative Example 1 corresponding to each installation posture. Figure 8 The postures of (a) to (c) are shown in the figure, and the XY plane is used as the horizontal plane for installing the electronic control device. Figure 8 (a) is an example in which the electronic control devices 100 and 101 are installed so that the direction of gravity is the -Z direction. Figure 8 (b) is an example in which the electronic control devices 100 and 101 are arranged so that the gravity direction is in the +X direction. H One side and the second area R L The connector 8 and the Ethernet terminal 9 are arranged so as to be located in the +Y direction with respect to the -X direction which is the opposite side of the gravity direction on one side.

[0082] Figure 8 (c) is an example in which the electronic control devices 100 and 101 are installed so that the gravity direction is the +Y direction. In other words, the gravity direction is the Y direction, and the connector 8 and the Ethernet terminal 9 are installed so that they are located in the +Y direction which is the same as the gravity direction.

[0083] like Figure 8 As shown in (d), in all the setting postures, the junction temperature of Example 1 is lower than that of Comparative Example 1. In addition, the temperature difference of the junction temperature under different setting postures is 3.1°C in Comparative Example 1 and 0.8°C in Example 1. That is, the temperature difference of the junction temperature under different setting postures is smaller in the electronic control device 100 of Example 1 than in the electronic control device 101 of Comparative Example 1.

[0084] Therefore, it was confirmed that the electronic control device 100 of Example 1 has a higher heat dissipation effect than the electronic control device 101 of Comparative Example 1 in any installation posture, and can reduce the maximum junction temperature.

[0085] According to the electronic control device 100 of the first embodiment, the following effects are achieved.

[0086] (1) The electronic control device 100 includes a first electronic component 4a having a first calorific value, a second electronic component 4b having a second calorific value smaller than the first calorific value, a circuit board 3 on which the first and second electronic components 4a and 4b are mounted, and a housing that houses the first electronic component 4a, the second electronic component 4b and the circuit board 3 and includes a heat dissipation housing 1 that forms a heat dissipation structure for dissipating heat from the first and second electronic components 4a and 4b. The heat dissipation structure includes a heat dissipation block 13 that is thermally coupled to the first electronic component 4a and a plurality of plate-shaped heat dissipation fins 14 that are provided to extend outward from the outer periphery of the heat dissipation block 13.

[0087] As described above, the heat dissipation fins 14 are extended outward from the outer periphery of the heat dissipation block 13 to thermally couple the first electronic component 4 a that generates a large amount of heat to the heat dissipation block 13 , thereby improving heat dissipation.

[0088] (2) At least a portion of the heat dissipation fins 14 extends from the outer periphery of the heat dissipation block 13 toward the second electronic component 4b and is connected to the peripheral side portion 15 of the heat dissipation housing 1. Therefore, the heat generated by the electronic component 4a is smoothly transferred from the electronic component 4a having a large heat generation to the side portion 15d of the heat dissipation housing 1 via the electronic component 4b having a small heat generation, and the heat is efficiently dissipated.

[0089] (3) The electronic control device 100 has a circuit board 3, an electronic component 4a with a relatively large heat generation, an electronic component 4b with a relatively small heat generation compared to the electronic component 4a, and a housing including a heat dissipation housing 1. The heat dissipation housing 1 has a heat dissipation block 13 thermally coupled to the electronic component 4a, and a plurality of plate-shaped heat dissipation fins 14 provided on the outer periphery of the heat dissipation block 13, wherein at least a portion of the heat dissipation fins 14 extend toward the electronic component 4b and are connected to the peripheral side. Therefore, the heat generated from the electronic component 4a is absorbed by the heat dissipation block 13 and radiated to the outside, while being transported from the side of the electronic component 4a with a relatively large heat generation to the side 15d of the heat dissipation housing 1 via the electronic component 4b with a relatively small heat generation. Thus, the heat dissipation can be improved.

[0090] (4) The heat dissipation housing 1 has a main body 12 that holds a plurality of plate-shaped heat dissipation fins 14 and a heat dissipation block 13. The plurality of heat dissipation fins 14 have a predetermined height that protrudes substantially vertically from the main body 12 toward the side opposite to the electronic component 4a. The heat dissipation block 13 has an internal protrusion 13a that protrudes from the main body 12 toward the side opposite to the electronic component 4a, and an external protrusion 13b that protrudes from the main body 12 toward the side opposite to the electronic component 4a. Thus, an electronic control device 100 is provided that achieves a reduced height, increases the heat capacity of the heat dissipation block 13, increases the height (length in the Z direction) of the heat dissipation fins 14, and improves heat dissipation.

[0091] (5) The electronic control device 100 further includes a connector 8 mounted on the housing. The connector 8 is arranged in the second region R where the electronic component 4b is arranged. L Since the connector 8 is a heat generating component, it is arranged in the second region R where the heat generation is small. L In this way, the heat generation area can be dispersed, thereby improving the heat dissipation of the electronic control device 100 as a whole.

[0092] - Second Embodiment -

[0093] Fig. 9 It is a plan view of an electronic control device according to a second embodiment of the present invention.

[0094] The electronic control device 100 of the second embodiment has a structure in which the shape of the thin heat sink block 13 having a rectangular shape in plan view in the first embodiment is changed to a circular shape in plan view, and the overall shape is replaced with a thin cylindrical shape or a truncated cone shape.

[0095] The plate-shaped heat dissipation fins 14 extend from the outer periphery of the heat dissipation block 13 .

[0096] Although not shown, in the second embodiment, the layout of the electronic components 4a to 4d inside the housing is the same as that in the first embodiment, and the electronic component 4a, which is a high heat generating component, is arranged in the first region R opposite to the heat sink 13. H In the embodiment, the electronic component 4b as a low heat generating component is arranged in the second region R between the heat dissipation block 13 and the side portion 15d of the heat dissipation housing 1. L middle.

[0097] A plurality of heat dissipation fins 14 are connected to the circumferential surface of the heat dissipation block 13 which is circular in plan view, similarly to the first embodiment. These heat dissipation fins 14 include a first fin group of straight lines extending from the circumferential surface in the +X direction and the -X direction, a second fin group of curved lines consisting of straight lines extending from the circumferential surface in the +Y direction and the -Y direction and straight lines bent at the ends of the straight lines in the +X direction and the -X direction, and a third fin group of curved lines consisting of straight lines extending radially from the circumferential surface and straight lines bent at the ends of the straight lines in the +X direction and the -X direction.

[0098] The first to third fin groups will be described in detail.

[0099] A portion of the first fin group, that is, a portion of the heat dissipation fins 14 provided at the center of the heat dissipation block 13 in the Y direction, extends in parallel along the +X direction and is connected to the side portion 15d of the heat dissipation housing 1 via the electronic component 4b. The remaining fin group of the first fin group, that is, the heat dissipation fins 14 provided at the center of the heat dissipation block 13 in the Y direction, extends in the -X direction and is connected to the side portion 15c of the heat dissipation housing 1.

[0100] A portion of the third fin group, i.e., a portion of the heat dissipation fins 14 provided on the +X direction side compared to the center of the heat dissipation block 13 in the Y direction, extends radially from the outer periphery of the heat dissipation block 13, bends toward the side 15d of the heat dissipation housing 1 at different positions in the Y direction, and then extends parallel to the +X direction, and is connected to the side 15d of the heat dissipation housing 1 via the electronic component 4b, or is connected to the front portion 11. The remaining fin groups of the third fin group, i.e., the heat dissipation fins 14 provided in the -X direction compared to the center of the heat dissipation block 13 in the Y direction, extend radially from the outer periphery of the heat dissipation block 13, bends toward the side 15c of the heat dissipation housing 1 at different positions in the Y direction, and then extends parallel to the -X direction, and is connected to the side 15c of the heat dissipation housing 1.

[0101] A portion of the second fin group, that is, a portion of the heat dissipation fin 14 arranged on the -Y direction side compared to the central portion of the heat dissipation block 13 in the Y direction, extends parallel to the -Y direction, has an end portion in the -Y direction bent toward the side 15d of the heat dissipation housing 1, and then extends parallel to the +X direction, and is connected to the side 15d of the heat dissipation housing 1 via the electronic component 4b, and has an end portion in the -Y direction bent toward the side 15c of the heat dissipation housing 1, extends parallel to the -X direction, and is connected to the side 15c of the heat dissipation housing 1. The remaining fin groups of the second fin group, i.e., the heat dissipation fins 14 arranged on the +Y direction side compared to the central part of the heat dissipation block 13 in the Y direction, extend parallel to the Y direction, have an end in the Y direction bent toward the side 15c of the heat dissipation housing 1, and then extend parallel to the -X direction and connected to the side 15c of the heat dissipation housing 1, and have an end in the Y direction bent toward the side 15d of the heat dissipation housing 1, and then extend parallel to the +X direction and connected to the front part 11.

[0102] The other structures in the second embodiment are the same as those in the first embodiment.

[0103] In the second embodiment, the heat sink 13 with a large heat capacity is also thermally coupled to the first electronic component 4a. In addition, a plurality of plate-shaped heat sink fins 14 connected to the peripheral side of the heat dissipation housing 1 are provided on the outer periphery of the heat sink 13. The length of the portion extending along the length direction of each heat sink fin 14 is longer than the length of the portion extending along the width direction. Moreover, a portion of the heat sink fin 14 extends toward the electronic component 4b and is connected to the peripheral side. That is, a portion of the heat sink fin 14 is located in the second region R including the electronic component 4b having a smaller heat generation than the electronic component 4a. L Extend upward.

[0104] Therefore, in the second embodiment, the same effects (1) to (3) as those of the first embodiment are achieved.

[0105] In the second embodiment, the heat sink block 13 is formed into a cylindrical or truncated cone shape, but the cross-sectional shape of the heat sink block 13 may be formed into an elliptical shape or a polygonal shape such as a triangle or a pentagon.

[0106] In the above-mentioned embodiments, the outer shell is constituted by the heat dissipation case 1 and the lower case 2. However, an intermediate case may be interposed between the heat dissipation case 1 and the lower case 2, and the outer shell may be constituted by three or more cases.

[0107] In the above-mentioned embodiments, the heat dissipation housing 1 is exemplified as a box-shaped structure whose peripheral side is roughly bent downward. However, the heat dissipation housing 1 may also be a plate-shaped member without a bent portion. That is, the flat heat dissipation housing 1 may be arranged on the top surface of the peripheral wall forming the opening of the lower housing 2 to cover the electronic component storage space in the lower housing 2.

[0108] In the above-mentioned embodiments, a BGA type semiconductor device is exemplified as the electronic component 4a. However, the electronic component 4a may be an electronic component other than the BGA type.

[0109] In the above-mentioned embodiments, the electronic components 4a to 4d are mounted on one circuit board 3. However, the electronic components 4a to 4d may be mounted on different circuit boards. H The electronic components 4a, 4c, 4d arranged in the second region R L Furthermore, the electronic component 4a and the electronic components 4c and 4d may be mounted on different circuit boards by accommodating other circuit boards in the housing.

[0110] In this specification, the term “circuit board” is used to include one circuit board 3 and a plurality of circuit boards 3 .

[0111] In the above-mentioned embodiments, the heat sink 13 is arranged near the center of the heat sink 1 at a distance from the side portions 15a to 15d and the front portion 11 of the heat sink 1. However, the heat sink 13 may be arranged so that the rectangular sides 16a to 16d or a part of the circular outer periphery are connected to the side portions 15a to 15d or the front portion 11 of the heat sink 1. Alternatively, the heat sink 13 may be arranged at a corner of the heat sink 1.

[0112] In the above embodiments, the structure in which only the electronic component 4a is thermally coupled to the heat sink 13 is shown as an example. However, a plurality of heat sinks 13 may be provided to thermally couple with a plurality of electronic components having a large heat generation. Figure 4 The electronic component 4 c is shown thermally coupled to the heat sink 13 .

[0113] Although not shown in the figure, a through hole (or through hole) penetrating in the thickness direction of the circuit board 3 may be provided in the area of ​​the circuit board 3 opposite to the electronic component 4a with a large heat generation. By also providing a through hole in the circuit board 3, the heat generated by the electronic component 4a is conducted to the lower housing 2 via the through hole and the bottom surface of the circuit board 3, thereby improving the heat dissipation. In addition, in this case, a resin may be filled between the bottom surface of the circuit board 3 and the lower housing 2, or a heat sink block thermally coupled to the through hole may be provided on the lower housing 2. The thermal conductivity is increased by the resin or the heat sink block, so the heat dissipation is further improved.

[0114] Various embodiments and modifications have been described above, but the present invention is not limited to these contents. Other forms that can be considered within the scope of the technical concept of the present invention are also included in the scope of the present invention.

[0115] The disclosures of the following priority parent cases are incorporated herein by reference.

[0116] Japanese Patent Application 2018-176227 (filed on September 20, 2018)

[0117] Description of Reference Numerals

[0118] 1 Heat dissipation housing

[0119] 3 Circuit board (substrate)

[0120] 4a Electronic component (first electronic component)

[0121] 4b Electronic component (second electronic component)

[0122] 4c, 4d Electronic components (third electronic components)

[0123] 5. Thermal Conductive Material

[0124] 8 Connector (electrical connector)

[0125] 11 Front

[0126] 12 Main body

[0127] 13 Heat sink

[0128] 13a Internal ridge

[0129] 13b External ridge

[0130] 14 heat sink fins

[0131] 15a, 15b Side (side in length direction)

[0132] 15c, 15d Side (width direction side)

[0133] 16a~16d Edge

[0134] 17 Conductive adhesive material

[0135] 100 Electronic control unit

[0136] R H First Area

[0137] R L Second area.

Claims

1. An electronic control device, characterized in that: include: a first electronic component having a first heat generation; a second electronic component having a second calorific value smaller than the first calorific value; at least one third electronic component having a lower heat generation than that of the second electronic component; a circuit board having the first electronic component, the second electronic component, and the third electronic component mounted thereon; and A housing for accommodating the first electronic component, the second electronic component, the third electronic component and the circuit board, comprising a heat dissipation housing having a heat dissipation structure for dissipating heat from the first electronic component, the second electronic component and the third electronic component, The heat dissipation structure includes a heat dissipation block thermally coupled to the first electronic component, and a plurality of plate-shaped heat dissipation fins extending outward from an outer periphery of the heat dissipation block. The first electronic component and the third electronic component are arranged in a first area for arranging electronic components with a large heat generation, and the second electronic component is arranged in a second area for arranging electronic components with a smaller heat generation than the first area. A portion of the heat dissipation fin extends from the first region to the second region and is connected to a peripheral side portion of the heat dissipation housing.

2. The electronic control device according to claim 1, characterized in that: At least a portion of the heat dissipation fins extends from an outer peripheral portion of the heat dissipation block toward the second electronic component and is connected to a peripheral side portion of the heat dissipation housing.

3. The electronic control device according to claim 1, characterized in that: The housing is provided with a power connector for supplying power to the first electronic component and the second electronic component. The power connector is arranged on the second area side.

4. The electronic control device according to claim 1, characterized in that: The first electronic component is bonded to the circuit board via a conductive bonding material, and a thermal conductive material is sandwiched between a surface of the first electronic component on the side opposite to the circuit board and the heat sink.

5. The electronic control device according to claim 1, characterized in that: The heat dissipation housing has a main body portion that holds the plurality of heat dissipation fins and the heat dissipation block, the plurality of heat dissipation fins having a specified height that protrudes approximately vertically from the main body portion to the side opposite to the first electronic component side, and the heat dissipation block has an internal protrusion portion that protrudes from the main body portion to the side opposite to the first electronic component side, and an external protrusion portion of a specified height that protrudes from the main body portion to the side opposite to the first electronic component side.

6. The electronic control device according to claim 5, characterized in that: The inner raised portion of the heat dissipation block has an area substantially equal to or larger than an area of ​​a heat dissipation surface of the first electronic component in a plan view, and the outer raised portion has substantially the same height as the heat dissipation fin.

7. The electronic control device according to any one of claims 1 to 6, characterized in that: The heat dissipation housing has a rectangular shape having a pair of longitudinal side portions extending in the longitudinal direction and a pair of width side portions extending in the width direction. The first electronic component and the second electronic component are arranged at a distance from each other in the length direction. At least a portion of each of the plurality of heat dissipation fins extends in parallel along the longitudinal direction.

8. The electronic control device according to claim 7, characterized in that: The heat dissipation block is arranged closer to one of the width direction side portions than to the center in the longitudinal direction of the heat dissipation housing.

9. The electronic control device according to claim 7, characterized in that: The heat sink has a square or rectangular shape with four sides in a plan view. The heat dissipation fins are arranged on the respective sides.

10. The electronic control device according to claim 7, characterized in that: The heat sink has a circular or oval shape in a plan view, At least a portion of the heat dissipation fins is radially provided from an outer periphery of the heat dissipation block.

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