Device and method for dissipating heat from an electronic component of a motor vehicle

Abstract

The invention relates to a device and a method for dissipating heat from an electronic component (26) of a motor vehicle, comprising at least one cooler (12) having at least one connection face (16) which is designed such that via the connection face (16) heat can be dissipated from the electronic component (26) arranged on a circuit board (24), comprising at least one housing (18) which at least partially encloses the circuit board (24), wherein the housing (18) has at least one housing opening (19), wherein at least part of the cooler (12) is guided out of this housing opening (19), wherein a gap size (38) between the electronic component (26) and the connection face (16) is designed to be able to be set to different steps via at least one step-like arrangement (20, 21, 22, 23).

Description

[0001] Description

[0002] title

[0003] Device and method for cooling an electronic component of a motor vehicle

[0004] The invention relates to a device and method for cooling an electronic component of a motor vehicle according to the preamble of the independent claims.

[0005] State of the art

[0006] DE 102013206999 A1 discloses a control unit for a motor vehicle with a heat-conducting housing wall formed from a heat-conducting sheet metal and forming a heat sink. The heat-conducting housing wall is detachably connected to the housing and has an embossing in a region opposite the power semiconductor. The embossing brings the housing wall closer to the power semiconductor, so that a distance, in particular a gap dimension, between the housing wall and the power semiconductor before embossing is greater than a distance, in particular a distance between the housing wall and the surface area, after embossing.

[0007] The invention is based on the object of ensuring reliable heat dissipation of the electronic component. This object is achieved by the features of the independent claims.

[0008] Disclosure of the invention

[0009] By designing a gap between the electronic component and the connection surface that can be adjusted to different levels via at least one stepped arrangement, the appropriate gap, especially a small one, can be easily set for each specific control unit design. This allows for a high-performance thermal connection of the electronic component to be cooled to the control unit's cooler. At the same time, a stable and rigid system can be created that does not result in a deterioration in the vibration loads on the control unit.

[0010] In a practical development, the stepped arrangement is arranged on the cooler and / or on the electronic component and / or on the housing and / or on a component connected to the electronic component, in particular a printed circuit board. This provides a high degree of design freedom depending on the specific design of the specific control unit.

[0011] In a suitable refinement, at least one counter surface is provided that interacts with the stepped arrangement to adjust the gap. The counter surface is arranged on the cooler and / or on the electronic component and / or on the housing and / or on a component connected to the electronic component, in particular a circuit board. This allows for low mechanical complexity and high stability.

[0012] Particularly preferably, the stepped arrangement comprises several steps and / or plateaus and / or ledges and / or a further stepped arrangement. This allows the gap dimension to be adjusted perpendicular to the surface of the housing.

[0013] In a practical development, the stepped arrangement features several steps of varying heights. This allows for simple, precise adjustment of the gap size depending on the application and requirements.

[0014] In a practical development, the gap can be adjusted via a relative movement between the cooler and the housing and / or between the mating surface and the stepped arrangement. This makes it particularly easy to perform the corresponding adjustment mechanically. The relative movement is particularly expediently achieved via a linear and / or planar movement parallel to the surface of the connecting surface and / or via rotation. The desired relative movement can be achieved depending on the installation situation or production equipment.

[0015] In a practical further development, it is provided that, along the relative movement, in particular during a linear movement and / or during a rotation, the height of the steps of the stepped arrangement and / or of the further stepped arrangement changes discretely, in particular increases or decreases. This allows for a particularly simple adjustment of the desired gap size.

[0016] In a practical development, the stepped arrangement and / or the counter surface interacting with the stepped arrangement are arranged on an edge of the cooler that covers the housing opening. This allows for particularly simple and stable adjustment of the gap size and also offers the geometric possibility of integrated sealing of the control unit.

[0017] In a practical development, the counter surface interacting with the stepped arrangement is designed to project beyond the surface, such that this counter surface can cover at least parts of the stepped arrangement. This allows for a particularly simple and stable design, particularly for the cooler.

[0018] In a practical further development, after setting the desired gap, at least one connecting means is provided for fixing the cooler relative to the electronic component, wherein the connecting means interacts with an oversized through hole or elongated hole. This allows different fastening positions of the fastening means relative to the cooler to be covered, depending on the relative movement of the cooler relative to the electronic component. The offset can be easily compensated. The stability of the arrangement is further increased. The additional process steps make it particularly easy to further automate the manufacturing process and increase flexibility for different heights or geometries of the electronic component.

[0019] Further useful developments arise from further dependent claims and from the description.

[0020] Short description of the drawing

[0021] They show:

[0022] Figure 1 Overview of a control unit in side view,

[0023] Figure 2 is a schematic representation of a gap adjustment by transverse offset,

[0024] Figure 3 is a plan view of a linearly movable cooler and

[0025] Figure 4 is a plan view of a rotary adjustable cooler.

[0026] Embodiment of the invention

[0027] The invention is illustrated schematically using an embodiment and is described in detail below with reference to the drawing.

[0028] Figure 1 shows a control unit 10 in a side view. On a printed circuit board 24, an electronic component 26 to be cooled is arranged, for example, in the center. By way of example, further electronic components 29 to be cooled are arranged on the printed circuit board 24, but these components are characterized by lower power dissipation than the electronic component 26 to be cooled particularly reliably or with a particularly low heat transfer resistance. The electronic component 26 can, for example, be a so-called SIP (System-In-Place) or a component thereof and / or a so-called System-On-Chip SOC or another semiconductor with high power dissipation. The printed circuit board 24 can be arranged on or soldered onto another printed circuit board 30, for example the main board.In addition, further circuit boards 24 can be provided on the additional circuit board 30, depending on the application, with at least one electronic component 26 that also generates high power dissipation. For example, the circuit board 24 designed as a SIP, which includes an SOC as the electronic component 26, can be soldered onto the circuit board 30.

[0029] The printed circuit board 24 and / or the additional printed circuit board 30 can be at least partially enclosed by a housing 18. For this purpose, the printed circuit board 24 and / or the additional printed circuit board 30 are / are connected to the housing 18. The housing 18 has an opening 19. A cooler 12 is at least partially accommodated in this opening 19. The cooler 12 protrudes slightly outward, beyond the surface of the housing 18, thus enabling particularly good heat dissipation. The housing 18 can be, for example, a die-cast housing, but also a sheet metal housing or a plastic housing, etc.

[0030] The cooler 12 serves to dissipate heat from at least the electronic component 26 and also from the other electronic components 29. To minimize thermal contact resistance, the electronic component 26, 29 is thermally coupled to the cooler 12 via a thermally conductive material 28. The thermally conductive material 28 is arranged between the electronic component 26, 29 and a connection surface 16 on the cooler 12 for thermally connecting the cooler 12 to the electronic component 26 to be cooled. The connection surface 16 is divided into two areas, the one with the narrowest gap 38 or TIM gap (gap for TIM material (TIM: thermal interface materials or thermally conductive material 28; for example, thermally conductive pastes, flexible materials in the form of a cushion or pad, etc.)) to the electronic component 26 and the outer area, which serves to dissipate heat from the other electronic components 29 via thermally conductive material 28.A gap 38 to be minimized is formed between the connection surface 16 and the surface of the electronic component 26 to be cooled, as shown in more detail in Figure 2. The smaller this gap 38 is, the better the power loss of the electronic component 26 can be dissipated.

[0031] At least one stepped arrangement 20, 21, 22, 23 with associated counter surface 17 serves to minimize this gap 38. This occurs through a relative movement between the connection surface 16 of the cooler 12 and the electronic component 26, for example through a lateral (or planar) displacement 32 or through a rotation 36. The stepped arrangement 20, 21, 22, 23 can be arranged either directly on the cooler 12 (Figure 1) or with a component connected to the cooler 12 and / or with the electronic component 26 itself or with a component firmly connected to the electronic component 26, such as the printed circuit board 24 and / or the housing 18 (Figure 2) or the like. The stepped arrangement 20, 21, 22, 23 interacts with corresponding counter surfaces 17.The counter surface 17 interacting with the stepped arrangement 20, 21, 22, 23 can be arranged either directly on the cooler 12 (Figure 2) or with a component connected to the cooler 12 and / or with the electronic component 26 itself or with a component firmly connected to the electronic component 26, such as the circuit board 24 and / or the housing 18 (Figure 1) or the like. Typically, several stepped arrangements 20, 21, 22, 23 and corresponding counter surfaces 17 are present. This could, for example, involve four support points arranged at the corners (between the cooler 12 and the housing 18) or three support points for stable support with a minimal area.

[0032] In the exemplary embodiment according to Figure 1, the counter surfaces 17 are arranged on the housing 18, which in turn is connected to the printed circuit board 24 on which the electronic component 26 to be cooled is arranged. The counter surfaces 17 on the housing protrude slightly outward relative to the surface of the housing 18. The cooler 12 is initially arranged to be movable relative to the electronic component 26 to be cooled, in particular in a direction that influences the gap 38 between the surface of the electronic component 26 to be cooled and the connection surface 16 of the cooler 12.

[0033] The cooler 12 has a projection 13 on each side, which laterally covers the surface of the housing 18 and projects over the opening 19 of the housing, as if it were a collar or edge. In particular, the stepped arrangement 20, 21 can be arranged on the projection 13 of the cooler 12, for example, in the form of several steps and discrete changes in distance relative to the connection surface 16 and / or the counter surface 17(s).

[0034] In the exemplary embodiment according to Figure 1, the stepped arrangement 20, 21 on the cooler 12 comprises, for example, several, for example three, steps, wherein the steps are oriented with different heights d1, d2, d3 in the direction of the housing 18. On another side of the cooler 12, a further stepped arrangement 21 is also arranged, for example in the form of further, for example three, steps with the same heights d1, d2, d3. The two stepped arrangements 20, 21 of the cooler 12 or the two regions with steps are each oriented in an ascending or descending manner with respect to the plane of the connection surface 16 or with respect to the direction of the temporal displacement 32 and / or a rotation 36 described later.The height d1, d2, d3 of the respective, in particular opposite, steps either increases or decreases continuously, so that a relative movement 32 parallel to the plane of the connection surface 16 leads either to an increase or a decrease in the distance or the gap dimension 38 between the connection surface 16 and the surface of the electronic component 26 to be cooled.

[0035] For example, protruding surfaces such as cooling fins 14 are provided on the cooler 12 to effectively dissipate the heat to be dissipated to the environment as an air cooler. However, other cooling principles can be provided, such as a liquid cooler with, for example, circulating water as the cooling medium, etc. The cooler 12 can, for example, be made of a particularly heat-conducting material such as copper or be designed as a vapor chamber (a closed space filled with a heat-conducting medium that ensures particularly efficient heat dissipation through phase changes) or similar.

[0036] The embodiment according to Figure 2 shows stepped arrangements 22, 23 arranged on the housing 18. These steps protrude upwards relative to the top of the housing 18. The stepped arrangement 22, 23 interacts with a respective counter-surface 17 on the cooler 12. This counter-surface 17 is arranged on the outside of the projection 13 covering the opening 19 of the housing 18. This projection 13 ends in an edge region which encompasses the counter-surface 17, which extends towards the housing 18 and thus also covers the other projecting steps of the stepped arrangement 22, 23 without engaging.

[0037] At the beginning, the counter surface 17 is arranged, for example, on the second step from the inside of the stepped arrangement 22, 23 or on a section which causes a relatively large gap 38, compare the bottom drawing of Figure 2. The initial positioning on a middle step of the stepped arrangement 22, 23 is particularly advantageous since the minimum gap 38 can be reached particularly easily from the middle position without a large change in position or displacement 32.

[0038] The distance (gap 38) between the surface of the electronic component 26 and the support point of the cooler 12 or the connection surface 16 is measured through the opening 19 in the housing 18 after the circuit board 30, 24 has been installed in the housing 18. This can then be used to determine which step of the stepped arrangement 22, 23 the cooler 12 can be placed on. This can be changed, as can be seen, for example, in Figure 2, by a planar movement 32. If, for example, the cooler 12 is to be positioned deeper in the housing 18 (reducing the gap 38), it is positioned a short distance (for example, a few millimeters depending on the step geometry) further to the left and thus placed on a lower step of the stepped arrangement 22, 23. This results in a current gap 38 (original gap 38 reduced by d1, where d1 represents the height difference between the adjacent steps).If the gap 38 is to be further reduced, the cooler 12 can be placed further to the left onto a lower step of the stepped arrangement 22, 23 on the housing 18, so that, as shown in the upper drawing of Figure 2, an actual gap 38 is determined from the difference between the original gap 38 and d2 (d2 being a height difference between the original step and the current step). After measuring and precise positioning, the cooler 12 is inserted conventionally, for example using force-displacement control, and is pressed into place with thermally conductive material 28 (for example, TIM Dispens), pressed into place, and then fixed, for example, screwed in place (for example using fastening means 34 such as screws, as shown by way of example in Figures 3 and 4).

[0039] In the plan view according to Figure 3, it can be seen that a transverse offset or displacement 32 results in an overlap or lateral offset of the respective electronic components 26; 26.1, 26.2; 29. ​​This overlap or fundamentally possible maximum lateral displacement must be selected such that all electronic components 26; 26.1, 26.2; 29 can be sufficiently well thermally connected in all stages. Figure 3 also shows that, by way of example, two smaller circuit boards 24.1, 24.2, each with at least one electronic component 26.1, 26.2 to be cooled, are arranged on the further circuit board 30. A cooler 12.1, 12 is required for each circuit board 24.1, 24.2 or each electronic component 26.1, 26.2 to be cooled there.2 with correspondingly arranged in the corner regions stepped arrangements 20, 21 (arranged either on the housing 18 or on the cooler 12 as described in connection with Figures 1 and 2; only the projection 13 of the cooler 12 is schematically shown transparently so that the positions of the stepped arrangements 20, 21 are apparent), which can each be individually displaced via a lateral linear movement 32 to adjust the optimal gap 38. Furthermore, fastening means 34 are shown schematically, which, due to the possible displaceability of the cooler 12 relative to the housing 18, are each received in an oversized through-hole or in an elongated hole 40. These fastening means 34 serve for the final fixation of the cooler 12 relative to the electronic component 26 once the suitable gap 38 has been found after the suitable arrangement of the counter surface 17 on the suitable step of the stepped arrangement 20, 21.The oversized through-holes or elongated holes 40 (with washer, etc.) enable different fastening positions of the fastening means 24 depending on different gap dimensions 38 or different lateral displacements 32. Preferably, a corresponding thread is formed in the housing 18 for fastening, wherein the oversized through-hole or elongated hole 40 is arranged on the cooler 12, through which the fastening means 34 is guided and is screwed to the housing 18, for example. In the embodiment according to Figure 4, a change in the gap dimension 38 can be achieved by a rotation 36. For this purpose, the cooler 16 arranged in the opening 19 is preferably circular (as is the opening 19). Stepped arrangements 20, 21 are again located on the edge regions or projections 13 that cover the housing 18.As already mentioned at the beginning, the stepped arrangements 20, 21 can be arranged on the cooler 12 and / or on the housing 18 connected to the electronic component 26. In the exemplary embodiment, for example, four stepped arrangements 20, 21 are provided for sufficient mechanical stability. Corresponding fastening means 34 are located between the stepped arrangements 20, 21, with the elongated holes 40 (partially circular in shape) enabling a rotational movement 36 to a certain extent, also relative to the fastening means 34.

[0040] The stepped arrangements 20, 21, 22, 23 can comprise multiple steps and / or plateaus and / or shoulders, so that discrete changes in the gap dimension 38 can be achieved. The contact surfaces between the respective stepped arrangements 20, 21, 22, 23 and the corresponding counter surfaces 17; 22, 23 can be linear, point-shaped, circular, rectangular, etc.

[0041] An EMC gasket (e.g. made of FIPG (Form in Place Gasket (liquid during assembly)), CIPG (Cured in Place Gasket (hardened during assembly), FoF Fabric over Foam (fabric tube over foam core), tape, foam core, springs, etc.) can be inserted or arranged between the cooler 12 and the housing 18 along the connection surface 16 in order to fully shield the housing 18 electrically.

[0042] The electronic components 26 comprise, in particular, high-performance computer cores that perform particularly computationally intensive functions in the motor vehicle. These can be, for example, autonomous or semi-autonomous driving functions, infotainment, communication interfaces between different bus systems (Ethernet, CAN, LIN, etc.) or gateway functionalities, certain security applications for granting authorization, for example to access the motor vehicle from outside, or other operations in the motor vehicle associated with particularly high computing power. The electronic components 26 are particularly preferably high-performance processors, multi-core processors, or highly integrated circuits (SoC, system-on-chip), which are characterized by high power losses. The two electronic components 26 arranged on the respective printed circuit boards 24 are particularly preferably designed to be functionally redundant.If one electronic component 26 fails, the other electronic component 26 can take over the functionality of the failing electronic component 26.

Claims

Claims 1. Device for cooling an electronic component (26) of a motor vehicle, comprising at least one cooler (12) with at least one connection surface (16) which is designed such that the electronic component (26) arranged on a printed circuit board (24) can be cooled via the connection surface (16), comprising at least one housing (18) which at least partially encloses the printed circuit board (24), wherein the housing (18) has at least one housing opening (19), wherein at least a part of the cooler (12) is led out of this housing opening (19), wherein a gap dimension (38) between the electronic component (26) and the connection surface (16) is designed to be adjustable in different stages via at least one step-shaped arrangement (20, 21, 22, 23).

2. Device according to claim 1, characterized in that the step-shaped arrangement (20, 21, 22, 23) is arranged on the cooler (12) and / or on the electronic component (26) and / or on the housing (18) and / or on a component connected to the electronic component (26), in particular a printed circuit board (24, 30).

3. Device according to one of the preceding claims, characterized in that at least one counter surface (17) is provided which cooperates with the step-shaped arrangement (20, 21, 22, 23) for adjusting the gap size (38), wherein the counter surface (17) is arranged on the cooler (12) and / or on the electronic component (26) and / or on the housing (18) and / or on a component connected to the electronic component (26), in particular a printed circuit board (24, 30).

4. Device according to one of the preceding claims, characterized in that the step-like arrangement (20, 21, 22, 23) comprises several steps and / or plateaus and / or ledges and / or that a further step-like arrangement (22, 23) is provided.

5. Device according to one of the preceding claims, characterized in that the step-like arrangement (20, 21, 22, 23) has several steps of different heights (d1, d2, d3).

6. Device according to one of the preceding claims, characterized in that the gap size (38) can be changed via a relative movement (32, 36) between the cooler (12) and the housing (18) and / or between the counter surface (17) and the step-shaped arrangement (20, 21, 22, 23).

7. Device according to one of the preceding claims, characterized in that the relative movement takes place via a particularly linear or particularly planar movement (32) parallel to the surface of the connecting surface (16) and / or via a rotation (36).

8. Device according to one of the preceding claims, characterized in that along the relative movement, in particular during a linear movement (32) and / or during a rotation (36), a height of the steps of the step-like arrangement (20, 21, 22, 23) and / or of the further step-like arrangement (22, 23) changes discretely, in particular increases or decreases.

9. Device according to one of the preceding claims, characterized in that the step-shaped arrangement (20, 21, 22, 23) and / or the counter-surface (17) cooperating with the step-shaped arrangement (20, 21, 22, 23) is arranged on an edge or projection (13) of the cooler (12) covering the housing opening (19).

10. Device according to one of the preceding claims, characterized in that the counter surface (17) cooperating with the step-shaped arrangement (20, 21, 22, 23) is designed to project relative to the surface in such a way that this counter surface (17) can cover at least parts of the step-shaped arrangement (20, 21, 22, 23).

11. Device according to one of the preceding claims, characterized in that after setting the desired gap size (38) at least one connecting means (34) is provided for fixing the cooler (12) relative to the electronic component (26), in particular by a fixation compensating for a relative movement, which comprises a connecting means (34) which cooperates with an oversized hole or an elongated hole (40).

12. A method for cooling an electronic component (26) of a motor vehicle, comprising at least one cooler (12) with at least one connection surface (16) which is designed such that the electronic component (26) arranged on a printed circuit board (24) can be cooled via the connection surface (16), comprising at least one housing (18) which at least partially encloses the printed circuit board (24), wherein the housing (18) has at least one housing opening (19), wherein at least a part of the cooler (12) is led out of this housing opening (19), wherein a gap size (38) between the electronic component (26) and the connection surface (16) is set in different stages via at least one step-shaped arrangement (20, 21, 22, 23).

13. Method according to the preceding method claim, further comprising the following steps: measuring the gap size (38), determining a setting of the step-like arrangement (20, 21, 22, 23), in particular of the respective step, applying a relative movement (32, 36) between the cooler (12) and the electronic component (26) to set the desired gap size (38) and / or fixing the cooler (12) relative to the electronic component (26).

14. Method according to one of the preceding method claims, characterized in that the cooler (12) is positioned and / or a thermally conductive material (28) is applied between the cooler (12) and the electronic component (26) and / or that the cooler (12) is pressed onto a thermally conductive material (28) and / or that the cooler (12) is firmly connected to the housing (18) and / or the printed circuit board (24) and / or that a seal, in particular an EMC seal, is introduced between the cooler (12) and the housing (18).

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