Heat dissipation device, electronic device and motor vehicle

Abstract

Heat dissipation device (34) for dissipating operating heat (Q) generated during the operation of an electronic component (36), comprising: - a heat sink (32) for absorbing heat energy; and - a flexible thermally conductive transfer layer (10) for conducting the operating heat (Q) from the electronic component (36) to the heat sink (32); wherein the transfer layer (10) is formed to extend along a thickness direction (22) from a component outer surface (40) of the electronic component (36) to a heat sink surface (38) of the heat sink (32); wherein a matrix (12) forming the flexible thermally conductive transfer layer (10) is formed from an adhesion promoter (20); wherein a separating layer (26) is arranged on a transfer layer surface (24) which is perpendicular to the thickness direction (22) and which is to be arranged facing the heat sink surface (38) or the component outer surface (40) during operation, and which prevents a material bond between the transfer layer (10) and the heat sink surface (38) or the component outer surface (40).

Description

[0001] The invention relates to a heat dissipation device for dissipating operating heat generated during the operation of an electronic component, an electronic device for controlling a multitude of motor vehicle control processes, and a motor vehicle comprising the electronic device.

[0002] In future automotive computer architectures, a multitude of functions, i.e., vehicle control processes, will be integrated into high-performance computers. These high-performance computers generate a significant amount of heat during operation due to the high power output they require, which must be dissipated. Therefore, in future automotive computer architectures, the high-performance computers will be thermally coupled to a heat sink. Since these high-performance computers are very expensive, and there may be several hardware upgrades over their lifespan, it is necessary that the high-performance computer be installed in a vehicle, for example, in such a way that it can be easily replaced.

[0003] It is therefore necessary that, on the one hand, an efficient thermal contact is established between the heat sink and the high-performance computer, and on the other hand, the high-performance computer must also be able to be installed and removed multiple times.

[0004] Various solutions for heat dissipation from computing devices are already known from other application areas.

[0005] For example, there are special contact materials that can be installed between computing devices and metal heat sinks, allowing the computing devices to be easily installed and removed. However, the problem with these known contact materials is that, due to the roughness and lack of coplanarity of the surfaces of the elements being brought into contact, the thermal contact is insufficient to adequately dissipate the large amounts of heat generated by high-performance computers. Improving the roughness and coplanarity, however, requires the use of expensive materials or corresponding, equally expensive, production processes.

[0006] Another possibility is to apply a thermal break layer between the two elements to be thermally contacted, which adheres to both elements. However, the problem here is that such an adhesive thermal break material cannot simply be removed; after removal, parts of the thermal break material remain stuck to both elements. Therefore, the thermal break material would first have to be completely removed from both elements in order to be replaced with a new one. This also involves extensive process steps and is therefore undesirable.

[0007] US patent 7,023,089 B1 discloses a device consisting of a heat spreader, a silicon chip, and a thermal interface material (TIM). The TIM is positioned between the heat spreader and the silicon chip and consists of several layers of metals that can bond together when heated. Additional layers are also provided between the TIM and the heat spreader or silicon chip, the purpose of which is to strengthen the thermal contact between the TIM and the respective element.

[0008] US Patent 2018 / 0027691A1 discloses a composite thermal interface material comprising a first layer containing a first thermal interface material exhibiting first compliance characteristics. The first layer contains first graphite fibers oriented in a direction substantially orthogonal to a surface of the first layer. The composite thermal interface material further comprises a second layer containing a second thermal interface material exhibiting second compliance characteristics that differ from those of the first.

[0009] US Patent 2009 / 0279261A1 discloses an electronic device equipped with a cooling arrangement for cooling a module that can be inserted into the device by a user during operation. The cooling arrangement comprises a heat sink and sliding elements. The sliding elements are arranged to engage the module with a low-friction contact surface to facilitate insertion. The sliding elements are further arranged to form a thermally inductive bridge between the module and the heat sink. At least one of the heat sinks and the sliding element are resiliently deflectable, allowing the sliding element to be pushed out of the way by the module when the module is inserted or removed.

[0010] Another way to establish thermal contact between two elements is to use a thermal paste, which thermally bonds them together. However, the problem here is that this thermal paste adheres to both surfaces of the elements when they are separated. Additionally, thermal paste is inherently difficult to remove. In applications where the elements are difficult to access, such as in a vehicle body, removing the remaining thermal paste before installing a new computing element, such as a high-performance computer, becomes challenging. Furthermore, the application of the thermal paste is problematic, as excessive application can cause it to creep into areas of the system, potentially leading to damage.

[0011] Furthermore, it is known from other applications to thermally join two elements using a so-called phase change material (PCM). The PCM also adheres to both surfaces of the separated elements when they are disassembled. Here, too, it is difficult to completely remove the PCM if the elements are located in a hard-to-reach area of ​​a vehicle body. If the PCM is applied too thickly in certain areas of the elements, this can also lead to the PCM not conforming properly to the surfaces of the elements to be contacted when heated. As with thermal paste, there is also the problem that excess PCM can creep into other areas of the overall system and cause damage there.

[0012] Overall, the solutions known so far have the problem that thermal contact during operation cannot be guaranteed due to roughness and lack of coplanarity of the surfaces and / or that, in the event of separation of the thermally contacted elements, the material used remains stuck to both surfaces.

[0013] The object of the invention is therefore to propose a heat dissipation device for dissipating operating heat generated during the operation of an electronic component, which can be disassembled without leaving any residue.

[0014] This problem is solved with a heat dissipation device having the combination of features of claim 1.

[0015] An electronic device for controlling a multitude of motor vehicle control processes, which includes the heat dissipation device, and a motor vehicle which includes this electronic device, are the subject of the dependent claims.

[0016] Advantageous embodiments of the invention are the subject of the dependent claims.

[0017] A heat dissipation device for dissipating heat generated during the operation of an electronic component comprises a heat sink for absorbing thermal energy and a flexible, thermally conductive transfer layer for conducting the heat from the electronic component to the heat sink. The transfer layer extends along a thickness direction from an outer surface of the electronic component to a heat sink surface. A matrix forming the flexible, thermally conductive transfer layer consists of an adhesion promoter. A separating layer is arranged on a transfer layer surface perpendicular to the thickness direction, which, during operation, faces the heat sink surface or the component's outer surface. This separating layer prevents the transfer layer from bonding to the heat sink surface or the component's outer surface.

[0018] The heat dissipation device is accordingly designed such that the flexible thermally conductive transfer layer adheres to the electronic component on one side via a material bond, since the matrix forming the transfer layer is made of an adhesion promoter, but has a separating layer on the opposite transfer layer surface, so that the transfer layer does not adhere to the heat sink or the electronic component via a material bond.

[0019] In cases where the electronic component, such as a high-performance computer, needs to be installed in a vehicle in a replaceable manner, this transfer layer, along with the separating layer, can be bonded to an outer surface of the high-performance computer. The separating layer, and thus the non-adhesive transfer layer surface, is thermally coupled to the heat sink via a frictional connection. When the high-performance computer is removed from the vehicle body, the non-adhesive separating layer ensures that the transfer layer can be easily and cleanly removed from the heat sink. This leaves the heat sink with a clean, residue-free surface, allowing a new high-performance computer to be securely attached to this surface.

[0020] Conversely, it is also possible to adhere the transfer layer and the separating layer to the heat sink surface and then leave the transfer layer attached to the heat sink when the high-performance computer is removed. This results in a clean, residue-free outer surface for the high-performance computer.

[0021] Preferably, the transfer layer is formed from the matrix with thermally conductive particles embedded therein.

[0022] For example, the thermally conductive particles are formed by thermally conductive ceramic particles, with the matrix in particular being formed from an elastomer, especially an acrylic elastomer.

[0023] The matrix is ​​therefore not only made of a thermally conductive flexible material, but especially of an elastic material, and can thus advantageously compensate for unevenness, unplanarity and tolerances.

[0024] Preferably, the separating layer is formed from a plastic film.

[0025] This plastic film is advantageously non-adhesive and is applied to the surface of the transfer layer, which is later installed facing the heat sink or electronic component. The plastic film can be applied, for example, by lamination. This plastic film facilitates the easy removal of the high-performance computer from the heat sink.

[0026] The overall structure of the transfer layer, consisting of a flexible matrix with embedded thermally conductive particles and an additional separating layer made of a plastic film, ensures excellent thermal contact during operation of the high-performance computer, as the transfer layer conforms even to rough and non-coplanar surfaces. The plastic film is designed to be so thin that it does not impede the transfer layer's secure and stable adhesion to the heat sink. Furthermore, when the heat sink and high-performance computer are disassembled, the transfer layer remains completely attached to a defined outer surface of the high-performance computer and detaches without leaving any residue from the heat sink surface, and vice versa.

[0027] The adhesive properties of the transfer layer are therefore only used on one side of the transfer layer, while the other side is coated with a non-adhesive material.

[0028] An electronic device for controlling a multitude of motor vehicle control processes comprises a high-performance computer for processing a multitude of signals and the heat dissipation device described above, including the heat sink and the flexible thermally conductive transfer layer. The flexible thermally conductive transfer layer forms a material bond with an outer surface of the high-performance computer, wherein the separating layer and the heat sink surface are force-fitted together. Alternatively, the flexible thermally conductive transfer layer forms a material bond with a heat sink surface, wherein the separating layer and the outer surface of the high-performance computer are force-fitted together.

[0029] Preferably, the coefficient of sliding friction µ is Gbetween the interface layer and the heat sink surface or between the interface layer and the high-performance computer outer surface µ G ≤ 0.3.

[0030] This makes it possible to thermally couple the high-performance computer and the heat sink simply by sliding them together in a largely lateral direction.

[0031] Preferably, the adhesive force F is A between the interface layer and the heat sink surface or between the interface layer and the high-performance computer outer surface F A ≤ 1 kPa. The adhesive force F A This defines the force with which the high-performance computer or its outer surface adheres to the heat sink, and which must be overcome to separate the two elements. Simple vertical installation and removal is facilitated if the adhesive force F is A in an area of ​​F A ≤ 1 kPa moving.

[0032] A motor vehicle comprises a thermally conductive body and an electronic device as described above, including the high-performance computer and the heat dissipation device. The heat sink of the heat dissipation device is thermally coupled to the body of the vehicle, so that heat generated during the operation of the high-performance computer is dissipated via the body of the vehicle to an environment outside the vehicle.

[0033] The term "motor vehicle body" can refer to, for example, the chassis of a motor vehicle, but also to a cooling circuit, such as a water-bearing cooling circuit, which may also be thermally coupled to a heat exchanger.

[0034] This makes it possible to dissipate heat into the environment via the vehicle body, which also allows other electronic components in the vehicle to be cooled.

[0035] An advantageous embodiment of the invention is explained in more detail below with reference to the accompanying drawing. This drawing shows: Fig. 1 a schematic cross-sectional view through a flexible heat-conducting transfer layer; Fig. 2 A schematic sectional view through an electronic device in which the transfer layer consists of Fig. 1 is located between a heat sink and a high-performance computer; Fig. 3 A schematic sectional view through a motor vehicle in which the electronic device is made of Fig. 2 is thermally coupled to a motor vehicle body of the motor vehicle via the heat sink; Fig. 4 schematic diagrams showing a) the installation and b) the removal of the high-performance computer from the vehicle body Fig. 3 are represented by essentially lateral insertion or removal; and Fig. 5 schematic diagrams showing a) the installation and b) the removal of the high-performance computer from the vehicle body Fig. 3 are represented by vertical contact.

[0036] Fig. Figure 1 shows a schematic sectional view of a flexible, thermally conductive transfer layer 10. The transfer layer 10 is formed from a matrix 12 in which thermally conductive particles 14 are embedded. To ensure that the transfer layer 10 is flexible and elastic, the matrix 12 is preferably formed from an elastomer 16, for example, an acrylic elastomer. The thermally conductive particles 14 are preferably formed from thermally conductive ceramic particles 18. The matrix 12 is formed from an elastomer 16 that acts as an adhesion promoter 20. This means that the transfer layer 10 exhibits adhesive properties based on the properties of the matrix 12.

[0037] When this transfer layer 10 is applied to a surface, the transfer layer 10 adheres to this surface in a materially bonded manner due to the physical properties of the matrix 12.

[0038] Perpendicular to a thickness direction 22 in which the transfer layer 10 extends, the transfer layer 10 forms a transfer layer surface 24 on which a separating layer 26 in the form of a plastic film 28 is arranged. This plastic film 28 has such properties that a material bond is precisely prevented. The plastic film 28 is therefore non-adhesive.

[0039] Fig. Figure 2 shows a schematic sectional view through an electronic device 30, in which the Fig. The transfer layer 10 shown is arranged between a heat sink 32 and a high-performance computer 36. This setup serves to dissipate the operating heat Q generated during the operation of the high-performance computer 36, thus protecting it from overheating.

[0040] The transfer layer 10 and the heat sink 32 therefore form a heat dissipation device 34 for dissipating this operating heat Q away from the high-performance computer 36.

[0041] The high-performance computer 36 in Fig. 2 processes a large number of signals and generates a large amount of operating heat Q.

[0042] The transfer layer 10 is arranged coplanarly to a heat sink surface 38 of the heat sink 32 and is in contact with the heat sink surface 38, on which the separating layer 26 is applied, via the transfer layer surface 24. That is, the heat sink 32 and the transfer layer 10 are positively connected to each other.

[0043] In the thickness direction 22 on the opposite transfer layer surface 24, which faces the high-performance computer 36, the transfer layer 10 is bonded, i.e., adhesively bonded, to an outer surface 40 of the high-performance computer 36. Thus, there is a material bond between the transfer layer 10 and the high-performance computer 36.

[0044] The structure can also be configured – not shown in the figures – such that the material bond is formed between the transfer layer 10 and the heat sink 32, and the frictional bond is formed between the transfer layer 10 and the high-performance computer 36. In the following, reference will continue to be made to the first alternative described (material bond between transfer layer 10 and high-performance computer 36), but this second alternative (material bond between transfer layer 10 and heat sink 32) should also be understood.

[0045] If the high-performance computer 36 now needs to be removed from the electronic device 30, the heat sink 32 can simply remain in the electronic device 30, while the high-performance computer 36, with the transfer layer 10 adhered to it, is simply removed from the electronic device 30. No residues in the form of matrix material from the transfer layer 10 remain on the heat sink surface 38, since the separating layer 26 prevents the transfer layer 10 from adhering to the heat sink surface 38. The transfer layer 10, including the separating layer 26, remains completely attached to the high-performance computer 36.

[0046] Fig. Figure 3 shows a schematic sectional view through a motor vehicle 42 in which the electronic device 30, including the high-performance computer 36 and the heat dissipation device 34, is installed. The heat sink 32 of the heat dissipation device 34 is thermally coupled to the body 44 of the motor vehicle 42. During operation of the high-performance computer 36, operating heat Q is generated, which can then be dissipated via the transfer layer 10, the heat sink 32, and the body 44 into an environment 46 outside the motor vehicle 42. This allows for simple cooling of the high-performance computer 36. Alternatively or additionally, it is also possible to implement cooling of the high-performance computer 36 via a water cooling system running within the body 44 of the motor vehicle.

[0047] Since the heat dissipation device 34 is constructed as described above, the high-performance computer 36 can be easily removed from the vehicle body 44, even if the electronic device 30 is located in a very inaccessible location within the vehicle 42. This is because the high-performance computer 36, along with the attached transfer layer 10, can be easily removed from the heat sink 32 without leaving any residue.

[0048] Fig. 4 and Fig. Figure 5 shows examples of how the high-performance computer 36 can be installed and removed from the electronic device 30, for example, in Fig. 3 can be done.

[0049] Fig. Figure 4 shows in image a) the installation of the high-performance computer 36 into the electronic device 30, while image b) shows the removal of the high-performance computer 36 from the electronic device 30. The installation and removal situation in Fig. 4. The high-performance computer 36 is installed and removed by essentially lateral or oblique sliding it in and out relative to the heat sink 32. To enable such installation and removal, it is advantageous to have a coefficient of sliding friction µ. G between the separating layer 26 and the heat sink surface 38 µ G ≤ 0.3

[0050] Fig.Figure 5 shows another possibility for installing and removing the high-performance computer 36 from the electronic device 30. Here, the high-performance computer 36 is brought into vertical contact with the heat sink 32. For this purpose, in Figure a), during installation, the high-performance computer 36 is first positioned below the heat sink 32 at a distance and then pressed upwards so that the heat sink 32 comes into contact with the transfer layer 10. During removal, in Figure b), the contact between the heat sink 32 and the high-performance computer 36 is then broken by vertically separating the two elements, thus creating a distance between them, in order to remove the high-performance computer 36 from the electronic device 30. For this purpose, it is advantageous if an adhesive force F is present. A between the separating layer 26 and the heat sink surface 38 F A ≤ 1 kPa. Reference symbol list 10 Transfer layer 12 Matrix 14 thermally conductive particles 16 Elastomer 18 ceramic particles 20 liability mediators 22 Thickness direction 24 Transfer layer surface 26 Separation layer 28 plastic film 30 electronic devices 32 Heat sink 34 Heat dissipation device 36 high-performance computers 38 Heat sink surface 40 high-performance computer exterior surface 42 Motor vehicle 44 Motor vehicle bodies 46 Surroundings F A Adhesive force µ G coefficient of sliding friction Q Operating heat

Claims

[1] Heat dissipation device (34) for dissipating operating heat (Q) generated during the operation of an electronic component (36), comprising: - a heat sink (32) for absorbing heat energy; and - a flexible thermally conductive transfer layer (10) for conducting the operating heat (Q) from the electronic component (36) to the heat sink (32); wherein the transfer layer (10) is formed to extend along a thickness direction (22) from a component outer surface (40) of the electronic component (36) to a heat sink surface (38) of the heat sink (32); wherein a matrix (12) forming the flexible thermally conductive transfer layer (10) is formed from an adhesion promoter (20); wherein a separating layer (26) is arranged on a transfer layer surface (24) which is perpendicular to the thickness direction (22) and which is to be arranged facing the heat sink surface (38) or the component outer surface (40) during operation, and which prevents a material bond between the transfer layer (10) and the heat sink surface (38) or the component outer surface (40). [2] Heat dissipation device (34) according to claim 1, characterized by , that the transfer layer (10) is formed from the matrix (12) with thermally conductive particles (14) embedded therein. [3] Heat dissipation device (34) according to claim 2, characterized by , that the thermally conductive particles (14) are formed by thermally conductive ceramic particles (18) and / or that the matrix (12) is formed from an elastomer (16), in particular an acrylic elastomer. [4] Heat dissipation device (34) according to one of claims 1 to 3, characterized bythat the separating layer (26) is formed from a plastic film (28). [5] Electronic device (30) for controlling a variety of motor vehicle control operations, comprising: - a high-performance computer (36) for processing a large number of signals; and - the heat dissipation device (34) according to one of claims 1 to 4 with the heat sink (32) and the flexible thermally conductive transfer layer (10), wherein the flexible thermally conductive transfer layer (10) forms a material bond with a high-performance computer outer surface (40) of the high-performance computer (36), and the separating layer (26) and the heat sink surface (38) of the heat sink (32) are positively connected to each other, or wherein the flexible thermally conductive transfer layer (10) forms a material bond with a heat sink surface (38), and the separating layer (26) and the outer surface (40) of the high-performance computer (36) are connected to each other in a force-fit manner. [6] Electronic device (30) according to claim 5, characterized by , that a coefficient of sliding friction (µ G ) between the interface (26) and the heat sink surface (38) or between the interface (26) and the high-performance computer outer surface (40) µ G ≤ 0.3 [7] Electronic device (30) according to one of claims 5 or 6, characterized by that an adhesive force (F A ) between the interface (26) and the heat sink surface (38) or between the interface (26) and the high-performance computer outer surface (40) F A ≤ 1 kPa. [8] Motor vehicle (42), comprising: - a heat-conducting motor vehicle body (44); and - an electronic device (30) according to one of claims 5 to 7 with the high-performance computer (36) and the heat dissipation device (34), wherein the heat sink (32) of the heat dissipation device (34) is thermally coupled to the vehicle body (44), so that operating heat (Q) generated during the operation of the high-performance computer (36) is dissipated into an environment (46) outside the vehicle (42) via the vehicle body (44).

Images