Cooling assembly, control device, and control device system

The cooling arrangement using a vapor chamber with phase change material and flexible cooling devices addresses heat dissipation challenges in high-performance vehicle control devices, ensuring extended functionality and safety during thermal overload, particularly in autonomous driving scenarios.

WO2025016722A1PCT designated stage expired Publication Date: 2025-01-23CONTINENTAL AUTOMOTIVE TECHNOLOGIES GMBH +1
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Patent Information

Application Number
PCT/EP2024/068584
Authority / Receiving Office
WO · WO
Patent Type
Applications
Current Assignee / Owner
Priority Date
2023-07-18
Filing Date
2024-07-02
Publication Date
2025-01-23

AI Technical Summary

Technical Problem

Modern control devices in vehicles face challenges in heat dissipation, particularly in high-performance computer systems, where components like RAM and processors generate significant heat, leading to thermal overload and requiring complex cooling systems. Additionally, existing cooling systems often fail quickly due to high ambient and coolant temperatures, posing risks to vehicle safety in autonomous driving scenarios.

Method used

A cooling arrangement utilizing a vapor chamber with a phase change material and a thermally conductive coupling to dissipate heat effectively, combined with a flexible cooling device, such as an elastic bellows or cooling pad, to manage heat dissipation without the need for a second independent cooling system, ensuring continued functionality during bridging times.

Benefits of technology

The solution enhances heat dissipation capabilities, extends bridging time, and maintains component functionality even during cooling system failures, ensuring vehicle safety by effectively managing thermal loads and reducing the complexity and noise associated with traditional cooling systems.

✦ Generated by Eureka AI based on patent content.

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Abstract

The present invention relates to a cooling assembly comprising: at least one component to be cooled, in particular arranged on a circuit carrier; a vapour chamber (11, 31) that is arranged on the component to be cooled in such a way that it is thermally conductively coupled to the component to be cooled; a cooling device that is arranged on the vapour chamber (11, 31) in such a way that the cooling device is thermally conductively coupled to the vapour chamber (11, 31); and a phase-change material (19) that is arranged on the vapour chamber (11, 31) in such a way that the phase-change material (19) is thermally conductively coupled to the vapour chamber (11, 31).
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Description

[0001] Description

[0002] Cooling arrangement, control device and control system

[0003] The present invention relates to a novel cooling arrangement, in particular for a sensor or a control device, as well as a corresponding sensor or a corresponding control device, which has a cooling arrangement according to the invention, and a control device system or rack system, comprising at least one cooling arrangement according to the invention or at least one control device according to the invention.

[0004] Technological background

[0005] Modern means of transport such as motor vehicles, motorcycles, and aircraft are increasingly equipped with control units or control devices. For example, in the automotive sector, generic electronic control units (ECUs) or

[0006] Control devices are used to control actuators (brakes, engine, transmission, etc.) and / or sensors, as well as to calculate and control driving and assistance functions. For example, such control devices are part of driver assistance systems, which use sensors or sensor systems to detect the environment, recognize traffic situations, and support the driver, e.g., by braking or steering intervention or by issuing a visual or acoustic warning. Sensors or sensor systems for environmental detection are regularly used.

[0007] Radar sensors, lidar sensors, camera sensors, or similar sensors are used. The sensor data acquired by the sensors can then be used to draw conclusions about the environment, which can be used, for example, to classify objects and / or the environment or to create an environment model. Furthermore, environmental detection is almost indispensable in the field of (partially) autonomous driving, so there is particular interest in the further development and refinement of such systems.

[0008] An important aspect of electronic control units or control systems is heat dissipation or cooling. The heat to be dissipated from the electronic control unit can be dissipated to the outside, for example, through a thermally highly conductive housing, such as a metal housing. On the surface or at least on one side of the housing or system, for example, heat can be dissipated.

[0009] With the high power dissipation of a control unit housing, the challenge is to dissipate the heat as effectively as possible to protect the components inside the housing from overheating. Various types of cooling systems or cooling methods exist for this purpose, e.g., air cooling, possibly with cooling fins or cooling knobs, or a closed coolant circuit that can be connected to the control unit housing and flows coolant over a housing wall or its surface.

[0010] Generic electronic control units and control devices, which are increasingly being used in modern vehicles and in aviation, are increasingly becoming so-called high-performance computer systems (HPC). These systems generally have to function in ambient temperatures or with coolant temperatures of, for example, -40 to 80°C or more. In contrast, however, some electronic components in the control devices, in particular data storage modules such as RAM (Random Access Memory) or Flash modules or EEPROMs (Electrically Erasable Programmable Read-Only Memory), are often subject to very limited upper permissible temperatures. Furthermore, due to ever increasing data transfer speeds, but also to the need to avoid voltage drops or oscillations, fast data storage modules should be located as close as possible to the microprocessors or processors that control them.

[0011] High-performance processors (especially CPUs, GPUs, switches, ICs, or the like) are placed close to the high-performance processors, as this placement is usually what enables the required fast write and read speeds or communication speeds. These high-performance processors typically generate considerable waste heat, which in typical applications can significantly heat up much more heat-sensitive components in the immediate vicinity of the high-performance processors, and therefore the heat must be dissipated. With ever-increasing power dissipation, especially in high-performance processors, neighboring components are subjected to ever greater thermal stress, and the cooling systems must be increasingly complex to dissipate the resulting heat from the heat generators and the neighboring, sometimes more sensitive, components.

[0012] Such electronic control units or control systems are expediently subject to various requirements. These requirements, particularly for ADAS (Advanced Driver Assistance Systems) functions, but also for braking and steering functions, for example, must be designed in such a way that, in the event of a single fault in a control unit or the power supply or cooling system, at least a fallback function maintains operation or remains in operation until the vehicle is transferred to a safe state. This requirement means, for example, that in vehicles with extended autonomous capabilities, duplicate (redundant) control units and power supplies would have to be installed for the important functions.In the event of a single fault, full functionality is often no longer guaranteed at the fallback level. Rather, it is generally sufficient if the remaining sensors, control units, actuators, and power supplies, and of course the associated data communication paths, can still bring the vehicle into a safe state or to the safest possible location with sufficient reliability, for example, if the driver cannot take control of the vehicle or if the vehicle is autonomous. In the vast majority of cases, 90 or even 120 seconds are sufficient to bring a vehicle into a safe state after a failure. Longer bridging times, such as up to 15 or 30 minutes, are rarely required.In addition to the components mentioned, cooling is also a critical aspect, the functional reliability of which must be guaranteed even during these bridging times.

[0013] Generic control units are usually designed in such a way that components must still demonstrate (full) functionality at the highest ambient temperature, highest power loss and highest coolant temperature with the lowest coolant flow. This means that in the event of a cooling failure, control units often have to switch off after just a few seconds (e.g. 3 to 6 seconds) due to excessive temperatures or overtemperature in individual components. In addition, modern control units for vehicles are usually designed in such a way that full functionality must be ensured within the defined temperature range and also within the defined voltage range. In fully or partially automated vehicles, for example, there are situations in which automated ferry operation is not possible, or in which the system must stop automated ferry operation with advance notice, e.g.if the vehicle must be brought into a safe state automatically if the driver is not present. If, for example, fog or black ice, or certain vehicle limitations / defects are detected, a vehicle will refuse entry into automated ferry operation. An insufficient charge level or fuel supply can also prevent entry into automated ferry operation, as the vehicle would likely break down.

[0014] If several control units or systems are cooled together, for example, by a common airflow or fluid circuit (e.g., in a so-called rack system), a failure of the necessary fluid flow (coolant flow, airflow, or similar) can result in the failure of several control units at once. The problem here is that a second, truly independent (liquid) cooling circuit often seems impractical due to the considerable effort involved. In contrast, simple air cooling for control units with increased power dissipation often cannot generate the required power. This can, on the one hand, generate strong and undesirable noise and, on the other hand, requires a large amount of fluid or air volume.As a result, there is increased interest in solutions that make it possible to dispense with, for example, a second complete cooling system in high-performance computers (HPC) and other devices for manageable periods of time, usually in the single-digit or even double-digit range. Printed state of the art.

[0015] From DE 10 2020 104 614 A1, a device for a motor vehicle is known, comprising at least one component to be cooled, which has at least one semiconductor, and comprising a cooling device, by means of which the component to be cooled can be at least partially cooled and heat provided by the component can be dissipated to a heat sink. The cooling device is designed as a gravity-based vapor chamber, through which the heat can be dissipated to the heat sink using the two-phase thermosiphon effect. For this purpose, the gravity-based vapor chamber has a base element, which has a first side facing the component and a second side facing away from the first side and the component and facing an interior of the vapor chamber, whereby particularly advantageous cooling can be achieved. Furthermore, between the vapor chamber and the component to be cooled, if necessary.a ceramic layer, a contact layer, a sintered layer and several solder layers are provided.

[0016] Object of the present invention

[0017] The object of the present invention is to provide a generic cooling arrangement with which good heat removal from a component to be cooled (or the assembly components to be cooled) is achieved even during a bridging time and the disadvantages resulting from the prior art are overcome in a simple and cost-effective manner.

[0018] Solution to the task

[0019] The above object is achieved by the entire teaching of claim 1 and the subordinate claims. Advantageous embodiments of the invention are claimed in the subclaims.

[0020] The cooling arrangement according to the invention comprises at least one component to be cooled, which is arranged in particular on a circuit carrier (e.g., printed circuit board, circuit board, substrate, or the like), a vapor chamber arranged on one side of the component to be cooled in such a way that it is thermally conductively coupled to the component to be cooled (e.g., this can also be arranged and thermally conductively coupled to the component to be cooled via a thermal interface material (TIM), a solder, or an adhesive), and a phase change material (PCM) applied externally to the vapor chamber, such that the phase change material is thermally conductively coupled to the vapor chamber. Furthermore, a cooling device is provided, which is arranged, for example, on a side of the vapor chamber opposite the component to be cooled, such that the cooling device is thermally conductively coupled to the vapor chamber.This allows the heat absorbed by the first thermal component, which was generated by the component to be cooled, to be dissipated.

[0021] The present invention shows, among other things, an advantageous embodiment of a cooling arrangement, e.g., for control units, in particular high-performance computers (HPCs), or high-performance control units, without having to make major changes to the control unit structure. This, on the one hand, improves the general cooling effect and, on the other hand, ensures sufficient cooling, e.g., even for a short bridging period. The extension of the bridging time can also be influenced to a certain extent by the technical design or additional measures, e.g., at the software level.

[0022] The vapor chamber can expediently be made of metal, in particular copper and / or aluminum and / or alloys thereof. According to a particularly preferred embodiment, the vapor chamber can also consist of an aluminum-copper composite material and be manufactured, for example, as a so-called extruded part or impact-formed part. Such a design can be particularly suitable because aluminum is particularly versatile (e.g., compatible with the aluminum components used in cooling water circuits) and copper has excellent thermal conduction properties, so that the advantages of both materials can be combined. Aluminum or aluminum alloys are preferably used here. Depending on the metal and the set negative pressure, water, acetone, but also refrigerants such as those used in air conditioning systems, and other media can be used as liquids inside the vapor chamber.The vapor chamber comprises an inner volume made up of internal channels or regions in which, for example, some liquid is arranged at a reduced pressure. This liquid evaporates at the operating temperatures of the component to be cooled, so that the heat can be dissipated as long as liquid is available to evaporate. Within the scope of the invention, a vapor chamber is preferably used which preferably has a capillary structure inside a hermetically sealed vapor chamber housing (including external soldering or welding). This capillary structure, depending on the installation position, contributes to the transport or conveyance of condensed liquid in addition to gravity, in particular due to the capillary effect. The capillary effect can be implemented by surface structures or inserted materials on the inner wall of the vapor chamber.This allows the liquid contained within to reach the warmest points of the vapor chamber housing, where the liquid evaporates during operation. This fluid transport creates and maintains a cycle of physical state changes (liquid to gas to liquid, etc.). The housing of such vapor chambers can be realized with a cover and a base section, but can also be manufactured, preferably, from extruded profiles or impact-molded parts as a single-piece semi-finished product or in one piece.

[0023] Preferably, fluid cooling, in particular air cooling or liquid cooling, is provided as the cooling device. For example, liquid cooling is characterized by the fact that it can dissipate heat particularly effectively, thereby further improving the cooling performance. For example, water glycol, water, glycol or another coolant liquid can be used as the cooling medium. Furthermore, a gaseous fluid such as air, nitrogen or carbon dioxide can also be provided as the cooling fluid. Expediently, an elastic bellows or a cooling pad can be provided as the cooling device, which is made at least partially from flexible material and is arranged in such a way that the elastic bellows or the cooling pad adapts to the steam chamber and, if applicable.also clings to housing parts of the control device, wherein the flexible material is preferably metal foil, in particular aluminum foil or copper foil, and / or plastic foil and / or a laminate and / or a composite foil, which in particular comprises a metal foil and a plastic foil.

[0024] Furthermore, the cooling arrangement according to the invention can be provided with a housing, which is preferably made of metal or plastic. The housing can be, for example, a control device housing or a sensor housing for environmental or ambient detection, in which the component to be cooled is arranged, for example, on a circuit carrier (e.g., circuit board, substrate, or printed circuit board).

[0025] According to an advantageous embodiment of the present invention, the steam chamber can be part of the housing, in particular the control device housing or the sensor housing. In practical terms, the steam chamber can be an integral component of the housing, e.g., it can be a side wall of the housing, a cover, an inlay, a base, or the like. For this purpose, the steam chamber is preferably plate-shaped and can preferably be manufactured as an extruded profile or impact-molded part and / or from stamped part(s).

[0026] Alternatively or additionally, the cooling device can also be at least partially an integral part of the housing. For example, if the cooling device is designed as a liquid cooling or fluid cooling system, it can be integrated into the housing in such a way that the fluid channels or coolant channels are integrated into the housing of the control device or sensor.

[0027] Advantageously, the vapor chamber can have a structure, in particular ribs and / or knobs and / or pins and / or fins, on which the phase change material is arranged. In addition, cooling structures such as cooling ribs and / or cooling knobs and / or cooling pins and / or cooling fins can also be provided. These are, so to speak, part of the cooling device (e.g., air cooling) and are thus arranged as an integral component directly on the vapor chamber, so that the vapor chamber and cooling device can also be formed as a single piece or manufactured as a single component (e.g., extruded part, impact-formed part). The cooling structures serve, for example, to be surrounded by a cooling medium (e.g., air, water, coolant, or the like), thereby allowing heat to be dissipated. This allows effective cooling to be implemented in a particularly practical manner.

[0028] For the purposes of the invention, a phase change material (PGM) is understood to be a special type of heat storage device that absorbs and stores a large portion of the thermal energy supplied to it in the form of transition enthalpy, also called latent or hidden heat, for a phase change from solid to liquid. As long as the phase transition is not completely complete, the temperature of the material (and thus the temperature of the thermally connected vapor chamber or the component to be cooled) does not rise further despite the addition of heat. This allows very large amounts of heat to be stored or absorbed within a specific temperature range around the phase change. The selection of the respective phase change material (PGM) is based in particular on the required melting point, so that an application-specific selection can be made. For example, special salt hydrates or paraffins can be used as storage media.Preferably, the material used should absorb a lot of energy (enthalpy of fusion) while requiring little space so that sufficient “heat can be absorbed”.

[0029] The phase change material used preferably comprises a thickener, in particular a flow inhibitor, e.g. in the form of block polymers, which prevents the PCM mixture from liquefying in the operating temperature range. In addition, the thickener introduced also retains its flowability at higher temperatures, whereby the entire PCM mixture also retains its flowability at higher temperatures, thus simplifying the manufacturing process to a great extent. Furthermore, it is intended that the PCM mixture contains only enough thickener so that it no longer becomes stiff in the upper operating temperature range, but rather "pudding-like" or "cream-like" or "pasty", but is sufficiently solid in the operating state so that it does not "flow away". The PCM mixture can also contain material such as, for example:Graphite or metal fibers or particles or similar, which increases the thermal conductivity and which can improve or enable the thermal connection to fins, fins or pins on the vapor chamber.

[0030] Furthermore, the phase change material can be arranged on the steam chamber by arranging and / or fastening a knitted fabric, in particular a metal knitted fabric comprising a copper and / or aluminum mesh, on / to the steam chamber, which is filled with phase change material, in particular in a ball-like manner, for example by the knitted fabric created by the copper or aluminum mesh having spaces in which the phase change material is introduced, so that the spaces are filled with phase change material.

[0031] Alternatively or additionally, the phase change materials used can preferably be arranged or selected in such a way that their properties ensure that the phase change material cannot escape due to the influence of heat, vibration, aging and the like, preferably beyond its service life, and also cannot cause unpleasant odors, for example in the vehicle interior.

[0032] For this purpose, the phase change material can expediently also have a casing (e.g. vessel, reservoir or coating such as the like) in which the phase change material or the phase change material configured as a knitted fabric or ball is arranged and which is arranged on the first thermal component. The casing can be, for example, a plastic bag, a plastic housing, a polymer container or the like. The requirement for the casing is essentially a high degree of tightness so that the phase change material cannot escape from the casing beyond the service life of the component and virtually odor neutrality is guaranteed. On the one hand, the material of the casing should not secrete any toxic and / or olfactory-nuisance substances, and on the other hand, no toxic and / or olfactory-nuisance substances in the contents (PCM) can penetrate to the outside.For example, this can prevent the occupants of a vehicle from being bothered by odors caused by a corresponding control unit, which may be located close to the passenger compartment of the vehicle.

[0033] According to a preferred embodiment of the invention, a TIM or a TIM layer can be arranged between the vapor chamber and the component to be cooled. The arrangement according to the invention allows the thickness of the TIM layer(s) and / or the number of TIM layers to be reduced, significantly improving heat transfer from the component to be cooled to the vapor chamber. Furthermore, with this cooling arrangement, the TIM layer only needs to be applied very thinly, or can even be omitted entirely.

[0034] Conveniently, the cooling device and / or the phase change material can also be arranged on the vapor chamber in such a way that the cooling structures (e.g., cooling ribs and / or cooling knobs and / or cooling pins and / or cooling fins) of the vapor chamber engage or protrude into the cooling device and / or the phase change material. In a practical manner, the cooling device or the phase change material can exhibit a certain degree of flexibility, so that it "snuggles" against the cooling structures, i.e., the outer material is flexible and is pressed or molded onto the structure by the pressure generated by the filling or film material, in particular without any significant gap.

[0035] According to a particular embodiment of the present invention, the vapor chamber can be curved so that it has a deformation, in particular a curved or U-shaped or L-shaped deformation, which protrudes, for example, from the dimension of the housing (i.e. a part of the vapor chamber can be located at least partially outside the housing or control device housing in order to thereby achieve improved cooling performance or to be able to accommodate more phase change material in the vapor chamber). Furthermore, at least phase change material can be arranged in a larger volume, wherein structures (e.g. ribs and / or knobs and / or pins and / or fins and / or the like) can be present in the area, which engage in the phase change material or are arranged so as to engage with it.

[0036] Furthermore, the steam chamber and the cooling device can be designed as a single piece, so that one component encompasses both components and thus has two (cooling) properties. For example, the fluid cooling can be attached to the steam chamber or they can be manufactured as a single piece. Furthermore, additional channels could be attached to the steam chamber, e.g. by manufacturing the steam chamber as an extruded profile. The vehicle's cooling water supply, for example, could then be connected to the additional channels, which then directly cools the steam chamber wall. This can further increase thermal coupling. In addition, as already described, cooling structures can of course be arranged on the steam chamber, which are part of an air cooling system and are, for example, surrounded by an air flow.

[0037] Furthermore, the present invention claims a control device or a sensor (for example a radar sensor, lidar sensor, camera sensor, ultrasonic sensor or the like) which comprises a cooling arrangement according to the invention.

[0038] Furthermore, the present invention comprises a control device system or rack system which comprises at least one cooling arrangement according to the invention or at least one control device according to the invention. At least two control devices are provided, each having at least one component to be cooled and a vapor chamber arranged on the component to be cooled in such a way that it is thermally conductively coupled to the component to be cooled. Furthermore, a cooling device is provided which is arranged on the vapor chambers of the control devices in such a way that the cooling device is thermally conductively coupled to the vapor chambers of the at least two control devices. This ensures that, for example, only one fluid cooling system or only one cooling pad is required to absorb or dissipate heat from multiple vapor chambers.

[0039] According to an advantageous embodiment of the control device system according to the invention, the control devices can each have a control device housing, wherein the control device housings are mechanically connected to one another, in particular glued, welded, screwed, riveted or the like.

[0040] The component to be cooled can expediently be a microcontroller and / or a processor and / or a chip and / or an integrated circuit (IC) and / or a system-on-chip (SoC) and / or a semiconductor component and / or a circuit carrier and / or a battery and / or other electronic component parts or compositions thereof, which are arranged, for example, on at least one circuit carrier or printed circuit board and / or printed circuit board (PCB) and / or substrate.

[0041] Description of the invention based on exemplary embodiments. The invention is explained in more detail below using expedient exemplary embodiments. They show:

[0042] Fig. 1: a simplified schematic representation of an embodiment of a vehicle with a control device according to the invention;

[0043] Fig. 2: a simplified sectional view of an embodiment of a control device according to the invention; Fig. 3A: a simplified schematic sectional view of an embodiment of phase change material arranged on the vapor chamber;

[0044] Fig. 3B: a simplified schematic sectional view of an embodiment of coil-like phase change material;

[0045] Fig. 3C: a simplified schematic sectional view of an embodiment of phase change material with a shell;

[0046] Fig. 4: a simplified sectional view of a further embodiment of a control device according to the invention with two phase change material volumes arranged opposite one another on the steam chamber;

[0047] Fig. 5: a simplified sectional view of a further embodiment of the control device according to the invention with an extended steam chamber;

[0048] Fig. 6A-6J: simplified representations of embodiments of a steam chamber of a cooling arrangement according to the invention;

[0049] Fig. 7: a simplified sectional view of an embodiment of a control device system according to the invention with two control devices;

[0050] Fig. 8: a simplified sectional view of a further embodiment of a control device system according to the invention with two control devices;

[0051] Fig. 9: a simplified sectional view of a further embodiment of a control device system according to the invention with two control devices;

[0052] Fig. 10A: a simplified representation of an embodiment of a control device according to the invention with a vapor chamber comprising cooling fins and ribs and on which phase-change material is arranged; Fig. 10B: a simplified representation of an embodiment of a vapor chamber for a control device according to Fig. 10A;

[0053] Fig. 10C: a simplified representation of an embodiment of a vapor chamber for a control device according to Fig. 10A, comprising cooling fins and fins, wherein the phase change material and the fins are arranged in an interlocking manner, and

[0054] Fig. 11 : a representation of an embodiment of the relationship between the temperature at the component to be cooled and the melting of the phase change material after the occurrence of a fault event.

[0055] Reference numeral 1 in Fig. 1 denotes a vehicle with various actuators (steering 3, engine 4, brake 5), which has a control device 2 according to the invention (ECU, Electronic Control Unit or ADCU, Assisted and Automated Driving Control Unit), by means of which a (partially) automated control of the vehicle 1 can take place, e.g. by the control device 2 being able to access the actuators of the vehicle 1. In addition, the control device 2 has a memory unit, for example to store an algorithm, control instructions or patterns. Furthermore, the vehicle 1 has sensors for detecting the environment: a radar sensor 6, a lidar sensor 7 and a front camera 8 as well as several ultrasonic sensors 9a-9d, the sensor data from which are used for environment and object detection, so that various assistance functions, such as emergency braking assistant (EBA, Electronic Brake Assist), distance control (ACC, Adaptive Cruise Control), lane keeping control orA lane keeping assistant (LKA), parking assistant, or similar functions can be implemented. The assistance functions are implemented, for example, via the

[0056] Control device 2 or the algorithm stored therein. The cooling arrangement according to the invention can, in principle, be implemented in any of the sensors or control units or the control device 2.

[0057] An important aspect of generic cooling arrangements is that any thermal tolerance ranges and maximum limits of the components to be cooled should always be observed to avoid damage to the respective component. For example, when entering the automated driving function, the components should have a thermal distance of a few degrees Celsius or Kelvin from the shutdown temperature, e.g. 5 Kelvin or 10 Kelvin or 15 Kelvin or 20 Kelvin. This can be achieved by only initiating automated driving when the cooling medium of the cooling system is not at or close to the upper limit (maximum temperature or maximum temperature of the system), or if the components (which is often not possible) still have a few Kelvin reserves down to the maximum temperature.Designing for a truly lower starting temperature is unproblematic, as this rarely occurs anyway. When the ambient temperature is high and the vehicle is simultaneously subjected to high or extreme loads due to challenging ferry operations, autonomous operation is generally not initiated, and vehicles in autonomous operation generally do not (frequently) operate at their performance limits. However, a difference of a few Kelvin generally only extends the shutdown time very slightly, as the temperature rise gradient is very steep. In addition, buffer capacities, as well as the thermally low-impedance connection of heat sinks or heat spreaders, cooling fins, or fluid coolers to components that generate a lot of waste heat, often increase the time until the maximum temperature is exceeded by only a few seconds.Therefore, in addition to the previously described procedure for further extending the run-on time after cooling failure, the invention also proposes reducing the power loss of the affected heat-generating components (e.g. switching off or downclocking).

[0058] Fig. 2 shows a control device 2 according to the invention with a control device housing 10, wherein the connection of thermally critical components or components to be cooled is provided by means of a so-called "vapor chamber" or vapor chamber 11, which is preferably arranged close to the thermally critical components to be cooled by one or more elevations or projections 11a. A processor 12 and an IC component 13 are provided as components to be cooled in Fig. 2, for example. Between the vapor chamber 11 and the processor 12 or IC component 13, a layer of TIM 14 (Thermal Interface Material) is arranged. For the sake of clarity, however, this layer is shown in the figures to be much thicker than it is actually intended. The TIM 14 allows the components that thermally dissipate the most power to be connected or contacted as directly as possible.Other components to be cooled can also be connected either directly or by means of thermally conductive materials, e.g., aluminum or copper components (e.g., "copper blocks" or the like), using an additional TIM. The vapor chamber 11 is connected to the control device housing 10 or is designed as a side wall, cover, or inlay of the control device housing 10, and is thus an integral component of the control device housing 10, which is otherwise constructed in two parts. The vapor chamber 11 can be screwed, glued, riveted, or similarly connected to the housing. Furthermore, the components to be cooled are located on a circuit board 15, which is arranged or secured within the control device housing 10. Furthermore, further circuit boards 16 can also be arranged in the control device housing 10. In Fig.2, the circuit boards 15, 16 are designed as a so-called SOM (System on Module) comprising a circuit board 16 and an additional board (circuit board 15). The circuit boards 15, 16 can, for example, be clamped between two parts of the control device housing 10 and additionally secured by a sealing adhesive 17, as shown for circuit board 16. The circuit board 16 also has a connector plug 18, which serves to connect the circuit board 16 and the control device 2, respectively. Both circuit boards are also connected to each other via a connector plug (shown as a rectangle between the circuit boards). Furthermore, a fluid cooling system 20 is provided, which is connected to a fluid circuit or coolant circuit via inlet 20a and outlet 20b to dissipate heat from the vapor chamber 11. The fluid cooling system 20 is an integral part of the control device housing 10—as an "inlay" in the control device housing 10, so to speak.The control device housing 10 is designed as a water-conducting housing made of aluminum. The vapor chamber 11 is generally constructed in such a way that, during normal operation, heat is dissipated from the surface opposite the connected components, e.g., via a fluid cooling system or a flexible cooling pad through which fluid flows. The vapor chamber side, to which the components to be cooled are connected (e.g., via thermal conductive paste or TIM), is designed to have a comparatively large area, and increased distances to other electronic components are preferably created. The vapor chamber can preferably also protrude beyond the circuit carrier of the thermally very critical printed circuit board. With a suitable technical design, the vapor chamber 11 can be flat on the surface or form a type of step with the control device housing 10, i.e., it can either be raised compared to the control device housing 10 or be recessed into it.

[0059] Furthermore, so-called phase change material 19 or PCM (Phase Change Material) is applied or arranged on the vapor chamber 11, as shown in Fig. 3A, which, for example, has a volume of 50, 100, 200 ccm up to 1000 cm 3and more. A material should be used which is prevented from flowing away when the melting temperature is exceeded (when arranged on the vapor chamber by the manufacturer) by the addition of, for example, plastic and preferably block polymers or other substances, and which also achieves even better thermal conductivity through the addition of further thermally conductive substances, e.g. graphite or copper braid or copper particles or the like, in order to promote, among other things, more uniform melting of the phase change material 19. The thickness of the material can be a few millimeters or even a few centimeters and can be applied in such a way that, for example, higher components or housing areas can be left out (the figures are not shown entirely to scale). The use of additives with regard to thermal conductivity reduces the expenditure on the vapor chamber 11.Optionally, structures attached or provided on the vapor chamber 11, such as fins, pins, spikes, ribs, or the like, facilitate the arrangement of the phase change material and improve the melting behavior through better thermal coupling. According to a special embodiment, for example, highly thermally conductive copper or aluminum braiding can be arranged in a coil or woven pattern on the vapor chamber 11. The copper or aluminum braiding is then interlaced with phase change material, as shown in Fig. 3B, by creating a type of metal mesh 19a through the copper or aluminum braiding, into whose interstices 19b the phase change material is introduced. The woven pattern or woven pattern can preferably also interact with knobs or the like on the vapor chamber 11. This also significantly improves the thermal conductivity to the phase change material.The thickener, which prevents the phase change material from flowing away after it has reached its melting temperature, is preferably only introduced to such an extent that softening occurs, but no flowing away can occur during operation of the control devices in the temperature range. A viscous or pudding-like consistency can preferably be achieved in the hot state. When selecting the material, the less “thickener” (e.g. block polymers) used, the better the phase change material’s property of high melting energy absorption is retained. The flow prevention of the PCM mixture means that there is no need to provide a sealing housing around the water change material; however, a shell 19c can be provided, as shown in Fig. 3C, which encloses the phase change material. The mixture is preferably adjusted orchosen so that it is liquid at a temperature which is above the permissible melting temperature of the mixture (including block polymers) and can therefore be mixed well and also filled into the pressure chamber 11 (if necessary with pins, fins and the like). This (high) temperature is reached during the manufacturing process and during any necessary recycling of the material, but not during normal operation. Since it is primarily a mixture and not a solution of substances, the introduction process is carried out by heating and stirring the mixture, as well as preferably the introduction into the preheated steam chamber 11 and its possible structuring or ribbing (e.g. by thermal treatment and / or by means of a laser). Filling can preferably be carried out by pouring it into the desired preheated area, with leakage being prevented by means of bulkheads remaining on the product or by means of molded parts that can be removed again after solidification, e.g.made of silicone or Teflon, which are preferably reusable, can be prevented. The process of heating and cooling the steam chamber fin / pin structure by using the steam chamber 11 is particularly emphasized, as this allows for faster cycle times in production.

[0060] Fig. 4 shows an embodiment of the control device 2 in which a smaller fluid cooling 20 is provided compared to the embodiment according to Fig. 2, wherein the vapor chamber 11 is provided as an “inlay” in the housing cover part of the control device housing 10 and has phase change materials 19 attached to both sides of the vapor chamber 11.

[0061] The vapor chamber 11 shown in Fig. 5 is simultaneously a cover of the control device housing 10. In addition, the vapor chamber 11 is designed such that it extends out of the control device housing 10 as an extension or deformation 11b or has been extended in order to be brought closer to an externally arranged phase change material 19. Alternatively or additionally, the phase change material 19 can be connected on both sides via ribs, fins, pins, or the like, which can be arranged on the extension or deformation 11b. In such configurations, the phase change material 19 does not necessarily have to be positioned parallel to the control device housing 10, but can also be arranged in a different way (not shown in the figures). Furthermore, the deformation 1b can protrude from the control device housing 10 in any form or be accommodated within it.

[0062] Furthermore, the steam chamber 11 can be manufactured as an extruded profile or impact-molded part and / or stamped part(s) and / or the like and / or have ribs or pins or fins on the outside or outside (outside the chamber area), which can be produced in the process of lid production (extruded profile with ribs, or fins or pins by impact-mold process) or can be subsequently applied (e.g. produced via laser or soldered or the like), which form a good thermal connection with the phase change material or ensure a good thermal connection.

[0063] In Fig. 6A-6J, different design variants of the steam chamber 11 and the associated phase change material 19 are shown.

[0064] Vapor chamber 11 is shown in section, with the inner channels of vapor chamber 11 and an internal capillary structure (represented by serrations on the edge) being visible. Fig. 6A shows an embodiment of vapor chamber 11 which has neither cooling structures on the surface nor phase change material 19. Fig. 6B shows an embodiment of the vapor chamber which has ribs 21 on one side, whereas the vapor chamber 11 in Fig. 6C has ribs 21 on both sides. Fig. 6D shows an embodiment of the vapor chamber in which a phase change material 19 is arranged on one side, whereas in Fig. 6D the phase change material 19 is arranged on both sides. Fig. 6F and 6G show the design of the steam chamber 11 in which ribs 21 are arranged either on one side (Fig. 6F) or on both sides (Fig. 6G) and at the same time phase change material 19 is arranged, into which the ribs 21 extend or into which the ribs 21 engage.Instead of ribs 21, fins, pins, spikes, pyramid structures, or the like can also be provided in all embodiments as structures intended to enable improved heat transfer from the steam chamber 11 to the phase change material 19, so that the latter melts faster and more evenly. As a result, the phase change material 19 can also be made larger or thicker, thereby extending the bridging time. If such structures are not provided, the phase change material 19 can also be applied without them, but then possibly more thinly, or possibly arranged over a knitted fabric or metal knitted fabric 19a. According to one embodiment of the steam chamber 11, it can comprise an aluminum housing, which is preferably in direct contact with the water flow.If a copper vapor chamber is used in an aluminum-based cooling circuit, a foil or coating can optionally be introduced as a separating medium between an attached water cooling unit including the fluid cooling fluid and the vapor chamber and / or housing parts. This optionally also provides a sealing effect for the assembled part to ensure chemical (galvanic) separation from the fluid medium. Furthermore, Fig. 6H shows a configuration of a multi-part vapor chamber 11 prior to assembly, comprising two larger parts (base 23 and cover 24) and supports 25 located between them, which then create inner walls during assembly by joining the individual parts, e.g., by soldering or welding (e.g., assembled stamped parts).The base 23, the lid 24, and the supports 25 also have a capillary structure (serration on the inner wall—however, the capillary structure could also be realized by a different design). Furthermore, Fig. 6I shows a design of the steam chamber 11 prior to assembly, in which two trough-like bases 23 form the steam chamber 11. Fig. 6J shows the steam chamber 11 from Fig. 6I in the assembled state. The multi-part steam chambers according to Figs. 6H-6J can of course also include cooling structures on the outside, which are not explicitly shown in the figures.

[0065] It is expressly mentioned here that all embodiments of the phase-change material 19 in the figures that are shown without structures, knitted fabrics, or casings could also include these. Furthermore, the vapor chamber 11 can also be made of copper, which, in combination with the flexible cooling pad, provides electrochemical separation of the cooling liquid and the copper vapor chamber (although copper generally has slightly better cooling properties than aluminum).

[0066] According to an advantageous embodiment, at least one elastic bellows or cooling pad can be provided as a cooling device (not shown in Fig. 2-4), which is at least partially made of flexible material, so that the elastic bellows or the flexible cooling pad conforms to the vapor chamber and, if applicable, also to the housing. The cooling pad can thus compensate for slightly different positional alignments of thermal components and / or the housing due to tolerances. In particular, this can be a cooling pad, as already described in DE 10 2021 209 640 A1.

[0067] Due to the flexible nature of the material, it conforms to the surrounding components such as the vapor chamber 11, particularly upon expansion (e.g., when filled with fluid). Metal foil, in particular aluminum foil or copper foil, and / or plastic foil and / or a laminate and / or a composite foil, which in particular comprises a metal foil and at least one plastic foil, can expediently be provided as the flexible material, since such foils can be produced and processed simply and cost-effectively. By providing a composite foil or a laminate as the flexible material, the durability and stability of the cooling arrangement can be easily improved. Furthermore, the flexible material can also have a coating, in particular an aluminum coating, in order to improve the properties with regard to stability, tightness, aging, and durability.In particular, anoxal coatings (anoxal process = an aluminum oxide layer is created on the surface of the aluminum by anodic polarization of the aluminum) or anodized coatings (anodized process = electrolytic oxidation of aluminum, whereby a protective oxide layer on aluminum is created by anodic oxidation) are also suitable for coating an aluminum foil. Furthermore, the cooling pad can be filled with a cooling medium or have a cooling medium flowing through it, wherein a fluid, in particular water, glycol, a water-glycol mixture, air, CO2, or the like, is provided as the cooling medium. Fig. 7 shows an embodiment of a control device system according to the invention, in which a stack comprising two control units or control devices 2, 30 with a liquid cooling system 20 or water cooling system located therebetween and glued or welded-in vapor chambers 11, 31.The control device 30 comprises a control device housing 30a, a vapor chamber 31, a component 32 to be cooled on a circuit board 33, and a connector 34. Furthermore, all other components can also be part of the control device 30 (which, however, are not described in detail for the sake of clarity). Furthermore, the control device 2 comprises a phase change material 19, which is arranged on the vapor chamber 11. The coolant flow should be switched off when the maximum temperature is reached in the event of a cooling system failure, so that cooling can then take place effectively via the phase change material 19. Furthermore, the control device 30, which is not cooled by a phase change material, should be switched off and / or shut down in a controlled manner in the event of a failure. Fig. 8 shows a similar configuration to Fig.7, wherein a flexible cooling pad 35 is provided as the cooling device, which is arranged between the steam chambers 11, 31 and can thus dissipate heat from both steam chambers 11, 31. In addition, Fig. 9 shows an embodiment of a control device system according to the invention, in which two similar control devices 2 are arranged next to one another, such that a fluid cooling system 20 is arranged between them, which is delimited on both sides by the steam chambers 11. The steam chambers 11 are designed as a cover of the respective control device housing 10 and at the same time are an integral part of the respective control device housing 10. Furthermore, the control device housings 10 are plugged into one another and in particular glued or welded to one another, so that the control device system forms a unit that cannot be easily removed.

[0068] Furthermore, Fig. 10A shows an embodiment of the control device 2 according to the invention, in which the vapor chamber 11 has phase change material 19, which is arranged on the vapor chamber 11. The vapor chamber 11 forms the cover of the control device housing 10. Furthermore, cooling fins 22 are provided as a cooling device (or also part of the cooling device if this is designed together with a fan), which can be produced, for example, during the manufacture of the vapor chamber 11 (e.g., by means of a laser, soldered on, welded on, or the like). Fig. 10B shows a further embodiment of the vapor chamber 11, which can be used in the control device 2 according to Fig. 9A and does not have external cooling fins. Furthermore, Fig.10C shows a further embodiment of the vapor chamber 11, in which external cooling fins 22 and additional external fins 21, which interlock with the phase change material 19, the phase change material 19 adapting to the fins 21 during production due to its material properties, as it is initially heated to a temperature which is above the “normal” operating temperature, so that the phase change material 19 can flow around the fins 21 and, after subsequent solidification, is distributed around them, so that the fins 21 protrude into or engage the phase change material 19. The heat is introduced into the phase change material 19 through the fins 21, so that the latter can then melt evenly, whereby the heat absorption or heat dissipation is particularly improved. The control device 2 according to Fig. 10A therefore has no liquid cooling (i.e. reduced power loss), e.g.Fan cooling (fan not shown) can be provided, which means that if the cooling effect fails, sufficient ventilation via the phase change material can still provide a run-on time or bridging time without overheating.

[0069] Fig. 11 shows the relationship between the temperature at the component to be cooled and the melting of the phase-change material after the occurrence of a fault event and, for example, the associated failure of a cooling system, which typically occurs in the implementations / design variants according to the invention. It is clearly visible here that the temperature of the component to be cooled can be kept virtually constant for several minutes even after the failure due to the melting of the phase-change material 19 and the associated heat absorption.

[0070] Of course, the cooling arrangement according to the invention can also be used to heat a component to be heated (as a heating device, so to speak) by filling it with a medium that transfers heat to the component to be heated. For this purpose, the cooling device can be easily connected to a heating circuit via the connections to be supplied with heating medium, which then flows through the cooling arrangement or heating device. For example, the rack according to the invention or the cooling arrangement according to the invention could also be used to heat one or more assemblies, particularly in the automotive sector.

[0071] 1 vehicle

[0072] 2 Control device

[0073] 3 Steering

[0074] 4 Engine

[0075] 5 Brake

[0076] 6 radar sensor

[0077] 7 Lidar sensor

[0078] 8 front camera

[0079] 9a-9d Ultrasonic sensor

[0080] 10 control unit housing

[0081] 11 Steam chamber

[0082] 11a lead

[0083] 11b Forming

[0084] 12 processors

[0085] 13 IC component

[0086] 14 TIM

[0087] 15 circuit board

[0088] 16 circuit board

[0089] 17 Sealing adhesive

[0090] 18 connectors

[0091] 19 Phase change material

[0092] 19a Metal mesh

[0093] 19b Intermediate space

[0094] 19c cover

[0095] 20 Fluid cooling

[0096] 20a Entrance

[0097] 20b Exit

[0098] 21 rib

[0099] 22 cooling fins

[0100] 23 Base 24 Lid

[0101] 25 Support

[0102] 30 Control device

[0103] 30a Control unit housing 31 Steam chamber

[0104] 32 processor

[0105] 33 circuit board

[0106] 34 connectors

[0107] 35 cooling pads

Claims

Patent claims 1. Cooling arrangement, comprising at least one component to be cooled, in particular arranged on a circuit carrier, a vapor chamber (11, 31) which is arranged on the component to be cooled in such a way that it is thermally conductively coupled to the component to be cooled, a cooling device which is arranged on the vapor chamber (11, 31) in such a way that the cooling device is thermally conductively coupled to the vapor chamber (11, 31), and a phase change material (19) which is arranged on the vapor chamber (11, 31) in such a way that the phase change material (19) is thermally conductively coupled to the vapor chamber (11, 31).

2. Cooling arrangement according to claim 1, characterized in that the vapor chamber (11,31) comprises a capillary structure arranged in the interior.

3. Cooling arrangement according to claim 1 or 2, characterized in that a fluid cooling, in particular an air cooling or a liquid cooling (20), is provided as the cooling device.

4. Cooling arrangement according to one of the preceding claims, characterized in that an elastic bellows or a cooling pad (35) is provided as the cooling device, which is made at least partially from flexible material and is arranged such that the elastic bellows or the cooling pad (35) conforms to the steam chamber (11, 31), wherein metal foil, in particular aluminum foil or copper foil, and / or plastic foil and / or a laminate and / or a composite foil, which in particular comprises a metal foil and a plastic foil, is provided as the flexible material.

5. Cooling arrangement according to one of the preceding claims, characterized in that a housing is provided, in particular a control device housing (10, 30a) or sensor housing, in which the component to be cooled is arranged.

6. Cooling arrangement according to claim 5, characterized in that the steam chamber (11,31) and / or the cooling device is at least partially an integral part of the housing.

7. Cooling arrangement according to one of the preceding claims, characterized in that the first vapor chamber (11, 31) has structures, in particular ribs (21) and / or knobs and / or pins and / or fins, between which the phase change material (19) is arranged.

8. Cooling arrangement according to one of the preceding claims, characterized in that the phase change material (19) comprises a thickener, in particular a flow inhibitor in the form of block polymers.

9. Cooling arrangement according to one of the preceding claims, characterized in that the phase change material (19) is arranged on the steam chamber (11, 31) in that a knitted fabric, in particular a metal knitted fabric (19a) comprising a copper and / or aluminum mesh, is arranged and / or fastened on / to the steam chamber (11, 31), the intermediate spaces (19b) of which are filled with phase change material.

10. Cooling arrangement according to one of the preceding claims, characterized in that the phase change material (19) has a shell (19c) in which the phase change material (19) is arranged and which is arranged on the steam chamber (11, 31).

11. Cooling arrangement according to one of the preceding claims, characterized in that a TIM (14) is arranged between the steam chamber (11, 31) and the component to be cooled.

12. Cooling arrangement according to one of the preceding claims, characterized in that the steam chamber (11, 31) and the cooling device are designed in one piece, so that one component comprises both components.

13. Cooling arrangement according to one of the preceding claims, characterized in that the steam chamber (11) has a, in particular curved or U-shaped or L-shaped, bent deformation (11b) which protrudes from the dimension of the housing, wherein at least one phase change material (19) is arranged on the deformation (11b).

14. Control device (2) or sensor comprising a cooling arrangement according to one of the preceding claims.

15. Control device system, comprising at least one cooling arrangement according to one of claims 1-13 or at least one control device (2) according to claim 14, comprising at least two control devices (2, 30), each comprising at least one component to be cooled and a steam chamber (11, 31) which is arranged on the component to be cooled in such a way that it is thermally conductively coupled to the component to be cooled, and a cooling device which is arranged on the steam chambers (11, 31) of the control devices (2, 30) in such a way that the cooling device is thermally conductively coupled to the steam chambers (11, 31) of the control devices (2, 30).

16. Control device system according to claim 15, characterized in that the control devices (2, 30) each have a control device housing (10, 30a) and the Control device housings (10, 30a) are mechanically connected to one another, in particular glued, welded, screwed, riveted or the like.

Citation Information

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