Electronic control device

Abstract

An electronic control device includes a liquid cooling unit, a first circuit board and a second circuit board mounted on one side and the other side of the liquid cooling unit, and a sheet-like transmission member electrically connecting the first circuit board and the second circuit board. The liquid cooling unit has a through-hole through which the sheet-like transmission member is inserted.

Description

Technical Field

[0001] This invention relates to an electronic control device. Background Technology

[0002] Electronic control devices installed in vehicles and other vehicles require high computing power to implement driver assistance systems such as collision damage mitigation braking and autonomous driving. Therefore, high-frequency integrated circuits are built into automotive electronic control devices. Along with this, the high-frequency electromagnetic noise emitted by electronic control devices is trending upwards. Under these circumstances, it is necessary to suppress high-frequency electromagnetic noise below the benchmark values ​​stipulated by laws in various countries. Furthermore, to achieve high integration in electronic control devices, there is a need for a configuration that electrically connects two circuit boards that respectively house electronic components.

[0003] Patent Document 1 describes an electronic control device configured such that a hollow cylindrical partition member through which a cooling medium (oil) flows is disposed between two circuit boards, and the two circuit boards are electrically connected by a board-to-board connector (B to B connector).

[0004] Existing technical documents

[0005] Patent documents

[0006] Patent Document 1: Japanese Patent Application Publication No. 2011-171163 Summary of the Invention

[0007] The problem that the invention aims to solve

[0008] However, in the electronic control device described in Patent Document 1, the partition beam member disposed between the two circuit boards is divided into two parts, thereby utilizing the space ensured between the two partition beam members to arrange the board-to-board connector. Therefore, there is a disadvantage that noise can easily propagate between the two circuit boards. Furthermore, due to the existence of the aforementioned space, the size of the partition beam member is limited, resulting in a corresponding reduction in cooling efficiency.

[0009] The purpose of this invention is to provide an electronic control device that can suppress the propagation of noise between two circuit boards and achieve high cooling efficiency.

[0010] Methods for solving problems

[0011] To solve the above problems, for example, the configuration described in the claims may be adopted.

[0012] This application includes various means to solve the above-mentioned problems. One example is an electronic control device comprising: a liquid cooling unit having a first main surface and a second main surface; a first circuit board mounted on the first main surface side of the liquid cooling unit; a second circuit board mounted on the second main surface side of the liquid cooling unit; and a sheet-like transport member electrically connecting the first circuit board and the second circuit board. The liquid cooling unit has a through hole for inserting the sheet-like transport member.

[0013] The effects of the invention

[0014] According to the present invention, noise propagation between two circuit boards can be suppressed, and high cooling efficiency can be achieved.

[0015] Other issues, structures, and effects not mentioned above will be clarified through the following description of the implementation methods. Attached Figure Description

[0016] Figure 1 This is a perspective view showing an example of the configuration of an electronic control device in an embodiment.

[0017] Figure 2 It is a section cut along line II-II. Figure 1 The cross-sectional view of the electronic control device shown.

[0018] Figure 3 yes Figure 1 An exploded view of the electronic control device shown.

[0019] Figure 4 This is a diagram showing the sheet-like transmission member of the electronic control device in the embodiment, viewed from the front.

[0020] Figure 5 It is a section cut along the VV line. Figure 4 The cross-sectional view of the sheet-like transmission component is shown.

[0021] Figure 6 This is a partial top view of the liquid cooling unit included in the electronic control device of the embodiment, viewed from the side of the first circuit board.

[0022] Figure 7 This is a diagram illustrating an example of the assembly sequence of the electronic control device in an embodiment (one of the examples).

[0023] Figure 8 This is a diagram (second example) illustrating the assembly sequence of the electronic control device in an embodiment.

[0024] Figure 9 This is a diagram (third one) illustrating an example of the assembly sequence of the electronic control device in the embodiment.

[0025] Figure 10This is a diagram (fourth one) illustrating an example of the assembly sequence of the electronic control device in an embodiment.

[0026] Figure 11 This is a diagram (fifth) illustrating an example of the assembly sequence of the electronic control device in an embodiment.

[0027] Figure 12 It is a diagram showing the configuration of the through holes and sheet-like transmission components of the liquid cooling unit. Detailed Implementation

[0028] Hereinafter, embodiments of the present invention will be described in detail with reference to the accompanying drawings. In this specification and the drawings, elements having substantially the same function or structure are labeled with the same symbols, and repetitive descriptions are omitted where appropriate. Furthermore, the following descriptions and drawings are examples for illustrating the present invention, and for ease of explanation, some omissions and simplifications are sometimes made. Each constituent element may be singular or plural unless otherwise specified. Additionally, for ease of understanding the invention, the positions, sizes, shapes, extents, etc., of the constituent elements shown in the drawings sometimes do not represent actual positions, sizes, shapes, extents, etc. Therefore, the present invention is not necessarily limited to the positions, sizes, shapes, extents, etc., disclosed in the drawings.

[0029] Figure 1 This is a perspective view showing an example of the configuration of an electronic control device in an embodiment. Figure 2 It is a section cut along line II-II. Figure 1 The cross-sectional view of the electronic control device shown. Figure 3 yes Figure 1 The diagram shows an exploded view of the electronic control device. In the following description, to clarify the shape and positional relationships of the various parts of the electronic control device, the height direction (thickness direction) of the electronic control device is designated as the Z-axis direction, one of the two axes orthogonal to the Z-axis direction is designated as the X-axis direction, and the other is designated as the Y-axis direction.

[0030] like Figures 1-3 As shown, the electronic control device 10 of this embodiment includes: a frame base 11, a frame cover 12, a liquid cooling unit 13, a first circuit board 14, a second circuit board 15, and a sheet-like transmission member 16. The first circuit board 14 is equivalent to a sub-board, and the second circuit board 15 is equivalent to a mother board. The first circuit board 14 is mounted on the liquid cooling unit 13 using first board mounting screws 17, and the second circuit board 15 is mounted on the liquid cooling unit 13 using second board mounting screws 18. The electronic control device 10 is, for example, an in-vehicle electronic control device used in autonomous driving, driver assistance systems, etc.

[0031] The frame of the electronic control device 10 is composed of a frame base 11 and a frame cover 12. The electronic control device 10 is preferably mounted on the vehicle with the frame base 11 facing upward and the frame cover 12 facing downward. Both the frame base 11 and the frame cover 12 are formed into quadrilaterals (including rectangles, squares, etc.) when viewed from above.

[0032] The frame base 11 and frame cover 12 are configured to sandwich the liquid cooling unit 13. The frame base 11 forms a first substrate storage space between itself and the liquid cooling unit 13, and a first circuit board 14 is stored in the first substrate storage space. The frame cover 12 forms a second substrate storage space between itself and the liquid cooling unit 13, and a second circuit board 15 is stored in the second substrate storage space.

[0033] The liquid cooling unit 13 is, for example, a casting made of aluminum (including aluminum alloy), and is shaped like a quadrilateral in plan view, similar to the frame described above. The liquid cooling unit 13 has a first main surface 13a and a second main surface 13b. A flow path (not shown) is formed inside the liquid cooling unit 13 for the flow of a liquid (cooling water, cooling oil, etc.) as a refrigerant. Furthermore, a first protrusion 21 is provided on the first main surface 13a, and a second protrusion 22 is provided on the second main surface 13b. Both the first protrusion 21 and the second protrusion 22 are integrally formed with the liquid cooling unit 13.

[0034] The first circuit board 14 is, for example, a rigid printed wiring board with glass epoxy as the substrate. The first circuit board 14 is mounted on the first main surface 13a side of the liquid cooling unit 13. More specifically, first screw insertion holes (not shown) are provided at the four corners of the first circuit board 14, and first screw holes (not shown) are provided on the first main surface 13a of the liquid cooling unit 13 in the same positional relationship as the first screw insertion holes. Furthermore, the first circuit board 14 is fixedly mounted on the first main surface 13a side of the liquid cooling unit 13 by inserting the first substrate mounting screw 17 into the first screw insertion hole and engaging it with the first screw hole of the liquid cooling unit 13.

[0035] A first electronic component 24 is mounted on the first circuit board 14. The first electronic component 24 is, for example, a high-frequency semiconductor device such as a CPU, MPU, or GPU, or a power semiconductor or other electronic component (heat-generating component) that generates a lot of heat per unit time. The first electronic component 24 is preferably thermally connected to the first protrusion 21 of the liquid cooling unit 13 via a thermally conductive adhesive, thermally conductive grease, or thermally conductive sheet (not shown). The number of first protrusions 21 and the number of first electronic components 24 can be arbitrarily varied. Additionally, a first connector 25 is mounted on the first circuit board 14. An insertion port (not shown) is formed on the first connector 25. This insertion port is formed as a long slit in the Y-axis direction.

[0036] The second circuit board 15 is, for example, a rigid printed wiring board with glass epoxy as the substrate. The second circuit board 15 is mounted on the second main surface 13b side of the liquid cooling unit 13. More specifically, second screw insertion holes (not shown) are provided at the four corners of the second circuit board 15, and second screw holes (not shown) are provided on the second main surface 13b of the liquid cooling unit 13 in the same positional relationship as these second screw insertion holes. Furthermore, the second circuit board 15 is fixedly mounted on the second main surface 13b side of the liquid cooling unit 13 by inserting second substrate mounting screws 18 into the second screw insertion holes, thereby engaging with the second screw holes of the liquid cooling unit 13 and tightening the second substrate mounting screws 18 in this state.

[0037] A second electronic component 27 is mounted on the second circuit board 15. The second electronic component 27 is, for example, a high-frequency semiconductor device such as a CPU, MPU, or GPU, or a power semiconductor, which generates a large amount of heat per unit time (heat-generating component). The second electronic component 27 is preferably thermally connected to the second protrusion 22 of the liquid cooling unit 13 via a thermally conductive adhesive, thermally conductive grease, or thermally conductive sheet (not shown). The number of second protrusions 22 and the number of second electronic components 27 can be arbitrarily varied. Additionally, a second connector 28 and an external connector 29 are mounted on the second circuit board 15. An insertion port (not shown) is formed on the second connector 28. This insertion port is formed as a long slit in the Y-axis direction. The external connector 29 is a connector used to connect the electronic control device 10 to external devices.

[0038] The sheet-like transmission member 16 is a thin member that electrically connects the first circuit board 14 and the second circuit board 15. Furthermore, the sheet-like transmission member 16 is a member that transmits electrical signals between the first circuit board 14 and the second circuit board 15. The sheet-like transmission member 16 is, for example, made of a flexible printed circuit board. The thickness of the sheet-like transmission member 16 is, for example, 60 μm or more and 100 μm or less.

[0039] like Figure 3 As shown, the sheet-like transmission member 16 has a first insertion portion 16a and a second insertion portion 16b. The first insertion portion 16a is the portion that inserts into the insertion port of the first connector 25. Multiple connection terminal portions are arranged in a predetermined arrangement on both the first insertion portion 16a and the first connector 25. Furthermore, by inserting the first insertion portion 16a into the insertion port of the first connector 25, corresponding connection terminal portions are electrically and mechanically connected to each other. The second insertion portion 16b is the portion that inserts into the insertion port of the second connector 28. Multiple connection terminal portions are arranged in a predetermined arrangement on both the second insertion portion 16b and the second connector 28. Furthermore, by inserting the second insertion portion 16b into the insertion port of the second connector 28, corresponding connection terminal portions are electrically and mechanically connected to each other.

[0040] A reinforcing plate 30 is attached to the sheet-like transport member 16. The reinforcing plate 30 is a component used to improve the rigidity of the sheet-like transport member 16. The reinforcing plate 30 is, for example, made of an insulating board such as polyimide, PET (polyethylene terephthalate), or glass epoxy, having a thickness dimension larger than the thickness dimension of the sheet-like transport member 16 (e.g., 0.2 mm to 0.3 mm). The reinforcing plate 30 is attached to the entire single surface of the sheet-like transport member 16, excluding the first insertion portion 16a and the second insertion portion 16b. The length of the reinforcing plate 30 is appropriately set according to the length (dimension in the Z-axis direction) of the sheet-like transport member 16. In addition, the reinforcing plate 30 is a component provided as needed.

[0041] Figure 4 This is a diagram showing the sheet-like transmission member of the electronic control device in the embodiment, viewed from the front (X-axis direction). Figure 5 It is a section cut along the VV line. Figure 4 The diagram shows a cross-sectional view of the sheet-like transmission component. Figure 4 and Figure 5 In the diagram, the X-axis direction corresponds to the thickness direction of the sheet-like transmission member 16, the Y-axis direction corresponds to the width direction of the sheet-like transmission member 16, and the Z-axis direction corresponds to the length direction of the sheet-like transmission member 16.

[0042] like Figure 4 and Figure 5 As shown, the sheet-like transmission member 16 has two ground wires 35 and six signal lines 36. The two ground wires 35 are formed at both ends of the sheet-like transmission member 16 in the width direction (Y-axis direction). The six signal lines 36 are formed between the two ground wires 35. The ground wires 35 and signal lines 36 are formed parallel to each other along the length direction of the sheet-like transmission member 16. One end of the ground wire 35 in the length direction is disposed on the first insertion portion 16a, and the other end of the ground wire 35 in the length direction is disposed on the second insertion portion 16b. Similarly, one end of the signal line 36 in the length direction is disposed on the first insertion portion 16a, and the other end of the signal line 36 in the length direction is disposed on the second insertion portion 16b.

[0043] Furthermore, the number of grounding wires 35 is not limited to two; it can be three or more. Additionally, the number of signal wires 36 can be arbitrarily changed. Furthermore, the grounding wires 35 and signal wires 36 are not limited to a single column; they can be arranged in multiple columns.

[0044] On the other hand, the liquid cooling unit 13 is provided with a through hole 31 for inserting the sheet-like transport member 16. The through hole 31 is configured to pass through the liquid cooling unit 13 from the first main surface 13a to the second main surface 13b.

[0045] Figure 6This is a partial top view of the liquid cooling unit included in the electronic control device of the embodiment, viewed from the side of the first circuit board.

[0046] exist Figure 6 In this context, the dimension L2 of the through hole 31 in the Y-axis direction is set to be greater than the dimension L1 of the sheet-like transmission member 16 in the Y-axis direction. Figure 5 Slightly larger. Furthermore, the two ends of the through hole 31 in the Y-axis direction are formed to be narrower than the other parts of the through hole 31 (in other words, the part near the center of the through hole 31). Specifically, the dimension W1 of the two ends of the through hole 31 in the Y-axis direction is set to be narrower than the dimension W2 of the other parts of the through hole 31.

[0047] Dimensions W1 and W2 are both dimensions of the through hole 31 defined in the X-axis direction. Furthermore, dimension W1 is the dimension between two opposing inner surfaces 31a in the X-axis direction within the inner surface of the through hole 31, and dimension W2 is the dimension between two opposing inner surfaces 31b in the X-axis direction. When the reinforcing plate 30 is attached to the sheet-like transport member 16, dimension W1 is set to be slightly larger than the thickness of the overlapping attachment of the sheet-like transport member 16 and the reinforcing plate 30. When the reinforcing plate 30 is not attached to the sheet-like transport member 16, dimension W1 is set to be slightly larger than the thickness of the sheet-like transport member 16.

[0048] Furthermore, a tapered portion 37 is formed at one end of the through-hole 31 in the depth direction (Z-axis direction). The tapered portion 37 is formed at a position opposite to the first circuit board 14. The tapered portion 37 is formed in an outwardly expanding shape such that the opening size of the through-hole 31 gradually increases as it approaches the first circuit board 14. The tapered portion 37 is formed to guide the sheet-like transmission member 16 into the through-hole 31.

[0049] When assembling the electronic control device 10 formed by the above-described configuration, such as Figure 7 As shown, the first insertion portion 16a of the sheet-like transmission member 16 is first inserted into the first connector 25 of the first circuit board 14 from the direction of the arrow. Thus, the first insertion portion 16a is connected to the first connector 25 by snapping or pressing. Additionally, as... Figure 4 The grounding wire 35 and signal wire 36 formed on the sheet-like transmission member 16 are electrically connected to the connection terminals of the corresponding first connector 25.

[0050] Next, as Figure 8 As shown, the sheet-like transfer member 16 is inserted into the through hole 31 of the liquid cooling unit 13 from the direction of the arrow. At this time, the sheet-like transfer member 16 is guided into the through hole 31 by the tapered portion 37. Therefore, the operability of assembly can be improved compared with the case where the tapered portion 37 is not provided.

[0051] Next, as Figure 9As shown, the sheet-like transport member 16 is inserted through the through hole 31 of the liquid cooling unit 13. In this embodiment, as... Figure 6 The two ends of the through hole 31 are narrowed, so when the sheet-like transmission member 16 is inserted into the through hole 31, the narrowed part (the inner surface 31a of the through hole 31) can be used as a guide to smoothly insert the sheet-like transmission member 16 into the through hole 31.

[0052] Next, as Figure 10 and Figure 11 As shown, the second insertion portion 16b of the sheet-like transmission member 16 is inserted into the second connector 28 of the second circuit board 15. At this time, warping, bending, and other deformations of the sheet-like transmission member 16 are suppressed by the reinforcing plate 30. Therefore, the insertion force applied to the sheet-like transmission member 16 via the first circuit board 14 is transmitted to the second insertion portion 16b through the reinforcing effect of the reinforcing plate 30. Therefore, the second insertion portion 16b can be connected to the second connector 28 by snapping or pressing. Thus, as... Figure 4 The grounding wire 35 and signal wire 36 formed on the sheet-like transmission member 16 are electrically connected to the connection terminals of the corresponding second connectors 28. In addition, the first circuit board 14 and the second circuit board 15 are electrically connected via the sheet-like transmission member 16.

[0053] Thus, with the first circuit board 14 and the second circuit board 15 electrically connected via the sheet-like transmission member 16, as follows: Figure 12 As shown, in the ground wire 35 and signal wire 36 formed on the sheet-like transmission member 16, the gap C1 between the forming portion of the ground wire 35 and the inner surface 31a of the through hole 31 is narrower than the gap C2 between the forming portion of the signal wire 36 and the inner surface 31b of the through hole 31. Therefore, the ground wire 35 is capacitively coupled to the liquid cooling unit 13 via the insulating layer of the sheet-like transmission member 16 and the gap C1. Thus, the ground wire 35 can be strengthened. On the other hand, the signal wire 36, due to the presence of a gap C2 wider than the gap C1, has reduced capacitive coupling with the liquid cooling unit 13. Therefore, the deterioration of SI (Signal Integrity) can be suppressed. Furthermore, in Figure 12 The marking for reinforcing plate 30 has been omitted.

[0054] In the electronic control device 10 of this embodiment, a configuration is adopted in which the first circuit board 14 and the second circuit board 15 are electrically connected via a sheet-like transmission member 16, and the sheet-like transmission member 16 is inserted into the through hole 31 of the liquid cooling unit 13. Therefore, compared to the case where the first circuit board 14 and the second circuit board 15 are electrically connected via a board-to-board connector (not shown), the size of the through hole 31, which becomes a noise propagation path, can be reduced. Thus, the propagation of noise between the first circuit board 14 and the second circuit board 15 can be suppressed. Furthermore, by reducing the size of the through hole 31 as described above, a larger size of the liquid cooling unit 13 can be ensured, achieving high cooling efficiency.

[0055] The scope of the present invention is not limited to the above-described embodiments. It also includes various modifications and improvements made within the scope of the specific effects that can be derived from the constituent elements of the invention and their combination.

[0056] For example, in the above embodiments, a flexible printed wiring substrate is cited as an example of a sheet-like transmission member, but it is not limited to this. The sheet-like transmission member may also be constructed from a flat cable or the like. Alternatively, the sheet-like transmission member may be constructed from a rigid printed wiring substrate having the same thickness as the flexible printed wiring substrate or the flat cable.

[0057] Furthermore, in the above embodiment, when the tapered portion 37 is formed in the through hole 31, in Figure 2 A tapered portion 37 is formed on the upper surface side of the liquid cooling unit 13, but it is not limited to this; a tapered portion may also be formed on the lower surface side of the liquid cooling unit 13.

[0058] Explanation of symbols

[0059] 10… Electronic control device, 13… Liquid cooling unit, 13a… First main surface, 13b… Second main surface, 14… First circuit board, 15… Second circuit board, 16… Sheet-shaped transmission member, 30… Reinforcing plate, 31… Through hole, 31a, 31b… Inner surface, 35… Grounding wire, 36… Signal line, 37… Tapered portion 37.

Claims

1. An electronic control device, characterized by comprising: Possessing: a liquid cooling unit having a first main surface and a second main surface; a first circuit substrate mounted on the first main surface side of the liquid cooling unit; a second circuit substrate mounted on the second main surface side of the liquid cooling unit; and a sheet-shaped transmission member electrically connecting the first circuit substrate and the second circuit substrate, the liquid cooling unit has a through-hole for the sheet-shaped transmission member to pass through.

2. The electronic control device according to claim 1, wherein the sheet-shaped transmission member has at least two ground lines formed at both ends in a width direction of the sheet-shaped transmission member, and a signal line formed between the at least two ground lines, a gap between the formed part of the ground line and an inner surface of the through-hole is narrower than a gap between the formed part of the signal line and the inner surface of the through-hole.

3. The electronic control device according to claim 1, wherein a reinforcing plate is attached to the sheet-shaped transmission member.

4. The electronic control device according to claim 1, wherein an outwardly expanding tapered portion is formed at one end in a depth direction of the through-hole.

5. The electronic control device according to claim 1, wherein both ends of the through-hole in a width direction of the sheet-shaped transmission member are formed to be narrower than other portions of the through-hole.

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