Cooling device and printed circuit board housing comprising same

Abstract

The invention relates to a cooling device and a printed circuit board housing including the same. The cooling device (11) is made of extruded aluminum profiles and is provided with a plurality of longitudinally penetrating channels (17) formed by an extrusion process. The device can be used as an outer wall / cover of a printed circuit board housing (10). The profile (11) comprises an inward projection (18b), for example formed by making a recess (18a) on an opposite surface, and the position of the projection coincides with the channel. This structure enables contact with electronic components of different heights on the circuit board (14). During use, cooling liquid flowing through the channels (17) and located behind the protrusions (18b) can take away heat generated by the electronic elements (19) of the printed circuit board (14).

Description

Technical Field

[0001] This disclosure relates to a cooling device for cooling multiple electronic components mounted on a circuit board, and a corresponding circuit board housing / enclosure including the cooling device. This disclosure is particularly relevant to cooling cold plates for electronic control units in automotive applications. Background Technology

[0002] Some electronic components generate heat during use, which can affect their functionality or even cause damage. Therefore, electronic circuits are typically equipped with cooling devices to maintain their operating temperature within an acceptable range. For particularly demanding applications, liquid cooling systems are often used due to their high cooling efficiency. Traditional liquid cooling systems usually feature a cold plate, which typically has a flat metal body with internal cooling channels or cooling pipe loops through which coolant circulates. In use, the cold plate is attached to the electronic component. When the component generates heat, the heat is transferred through the cold plate and cooling pipes to the coolant and then carried away from the circuit.

[0003] Cooling components sometimes have surface features that are configured to protrude toward and contact components on the circuit board, especially those that generate the most heat.

[0004] One known form of automotive electronic control unit (ECU) housing includes die-cast aluminum components, which require liquid cooling for the reasons mentioned above. The liquid cooling portion of the housing can also be made of die-cast material, with the liquid-containing cavity sealed by friction stir welding (FSW). This welding process exerts significant forces on the housing, thus requiring higher rigidity. Summary of the Invention

[0005] This disclosure relates to a cooling device, a corresponding printed circuit board (PCB) housing, and a method for manufacturing the cooling device for cooling multiple electronic components mounted on a circuit board. The cooling device can be used as a cold plate for an electronic control unit. Specifically, the present invention aims to provide an improved or at least alternative cooling device and a corresponding PCB housing / assembly, and to provide a cost-effective and / or highly efficient manufacturing method / process.

[0006] A first aspect of the invention relates, for example, to a cooling device for cooling a plurality of electronic components mounted on a circuit board, comprising: a profile (e.g., in the form of an extruded, relatively flat plate) having at least one channel extending longitudinally therethrough. The invention can also be described as: a cooling device for cooling a plurality of electronic components mounted on a circuit board in an electronic control unit, comprising: an extruded profile having at least one channel extending longitudinally therethrough between a first edge and a second edge; wherein the extruded profile is configured to have a first side serving as an outer wall of the electronic control unit and a second side serving as an interface for cooling the plurality of electronic components mounted on the circuit board. In this application, the terms "printed circuit board housing" and "electronic control unit" have the same meaning and are used interchangeably.

[0007] The surface of the profile / plate may be provided with at least one protruding feature structure configured to contact electronic components of the printed circuit board. In some embodiments, the protruding (e.g., embossed) feature structure is formed by pressing a corresponding recessed feature structure onto the opposite surface of the extruded plate using a pressing tool. In this way, longitudinal channels can serve as paths for coolant flow within the extruded plate profile, including through chambers adjacent to the surface feature structure, thereby cooling any electronic components in contact with that feature structure.

[0008] The cooling device can be used to form one wall of an electronic control unit (ECU), the housing of which houses a printed circuit board in contact with it. The opposing wall of the housing can be a pressed metal structure, such as a cover or tray, and has connecting features for fastening the cooling device (e.g., in the form of a plate or cover) thereto, with the printed circuit board mounted and housed between the two.

[0009] As previously mentioned, the printed circuit board mating surface of the cooling device / board can be designed with raised (e.g., embossed) areas and recessed (e.g., embossed) areas, the raised areas for mating with some components and the recessed areas for mating with other components. Depending on the condition of the mating surfaces (i.e., the different heights of the electronic components relative to the printed circuit board substrate), the raised areas and the recessed areas can have different heights and depths.

[0010] Importantly, the device is made from an extruded profile to create a simple and lightweight pressed cover that serves as part of the printed circuit board housing while also functioning as a liquid-cooled heat exchange device. In a second, broader aspect of the invention, a printed circuit board housing incorporating the aforementioned cooling device is provided.

[0011] In some embodiments, as described above, the component mating structure is formed by pressing a forming tool into the surface of an extruded profile. In other embodiments, the component mating structure / surface feature structure may also be formed in other ways and applied to the surface of the extruded profile.

[0012] In one form, a thermal interface material is applied to raised (and / or recessed) surface features to improve thermal contact with corresponding electronic components on a printed circuit board.

[0013] Based on the foregoing, one advantage of this cooling device is that it can serve as at least one complete wall of a printed circuit board housing. Theoretically, the second cooling device described in this invention can be used as a second wall of the printed circuit board housing, for example, as a wall opposite the first wall when components extend from both sides of the printed circuit board. In addition to accommodating components on the circuit board surface, one or both cooling devices / walls can be adapted to fit the printed circuit board itself through pressing.

[0014] The present invention recognizes the problem of how to integrate extruded profile cold plates into the housing of electronic control units and solves the problem by transforming extruded (e.g., aluminum) profiles into the housing wall itself.

[0015] The extruded profile becomes the cover of the housing, which, after modification, can be securely connected (e.g., by screws) to a printed circuit board and a sheet metal cover, thereby forming a complete housing. A third aspect of the invention relates to a manufacturing method.

[0016] As previously mentioned, similar to most cooling solutions, this invention uses a thermal interface material (TIM) to connect the heating element to the extruded aluminum profile (housing or cold plate). Preferably, the printed circuit board is designed / sized to fit the housing and the corresponding cooling device. In one form, the outer surface of the aluminum profile is corrosion-resistant.

[0017] According to the proposed solution, the cost and complexity of the shell are reduced, while the weight and size (thickness / height) are also reduced, forming a compact / flat profile structure.

[0018] In some applications, depending on the specific application, extruded profiles can be reinforced, for example, by forming reinforcing ribs during the extrusion process. Additionally, profiles can be reinforced by increasing the thickness of certain areas, omitting channels at the edges, and / or filling channels with reinforcing elements.

[0019] The opposite side covers of the printed circuit board housing can be made of pressed stainless steel or galvanized. The choice of material may depend on the rigidity achievable with the extruded profile. For example, reinforcing ribs can also be pressed into the opposite covers.

[0020] The coolant delivery system can be directly connected to the profile, for example, via clamps, adhesives, or other fasteners. The coolant is propelled in a straight line through a channel between the inlet and outlet. Theoretically, with a suitable coolant connection manifold, the channel can be configured to allow the coolant to flow in one direction and then in the opposite direction. Attached Figure Description

[0021] Exemplary embodiments will now be described with reference to the accompanying drawings, wherein:

[0022] Figure 1 An overall view of the printed circuit board housing, including the extrusion cooling unit, is shown.

[0023] Figure 2 A bottom view of the cooling device is shown;

[0024] Figure 3 Another bottom view of the cooling device is shown, revealing the printed circuit board in contact with its lower surface;

[0025] Figure 4 A bottom view of the outer casing is shown. Detailed Implementation

[0026] The following description provides exemplary embodiments and explains the principles of the invention in conjunction with the accompanying drawings. However, the scope of the invention is not intended to be limited to the precise details of the embodiments or to strictly follow all features and / or method steps, as various variations will be apparent to those skilled in the art, and these variations should also be considered to be included in this description. Terms used to describe elements herein should be interpreted broadly to also cover features with equivalent functionality. In some cases, multiple alternative terms (synonyms) are provided for structural features, but these terms are not intended to exhaustively describe all possible expressions. Descriptive terms should also be interpreted in the broadest sense; for example, the term "comprising" as used herein means "consisting of at least part of," and therefore, for any expression in this specification containing the word "comprising," there may be other features besides those preceding the term. Related terms such as "including" and "containing" should also be interpreted in the same way. Directional terms such as "vertical," "horizontal," "upper," "lower," "lateral," "upper," and "lower" are used for convenience of explanation only and are generally referred to with reference to the orientation shown in the drawings. These directional terms should not be considered as definitive limitations if equivalent functionality can be achieved through other dimensions and / or orientations. In fact, in this application, terms such as “horizontal” axis or “vertical” axis may be affected by the mounting orientation adopted by the housing structure. Therefore, all directional terms are relative terms.

[0027] The descriptions herein relate to implementations with specific combinations of steps or features, but it is conceivable that compatible steps or features between different implementations can be further combined and cross-combined. In fact, a single feature may constitute an invention independently without needing to be implemented in combination with other features, nor necessarily as a complete combination.

[0028] It should be understood that the illustrated embodiments are merely examples to explain the present invention. In practical applications, the present invention can be applied to a variety of different structures, and those skilled in the art can easily implement these embodiments.

[0029] Figure 1 A general view of the components of a printed circuit board housing 10 including a cooling device 11 according to the invention is shown. The housing 10 includes the cooling device 11, which serves as a cover and is connected to a bottom cover 12, which has a chamber 13 for receiving a printed circuit board (PCB) 14.

[0030] Fasteners 15 (e.g., fixing screws) connect the bottom cover 12 to the cooling device 11, while passing through the opening 16 at the corner 13 of the printed circuit board. In this way, after assembly, the printed circuit board 14 will be sandwiched in the middle and protected by the outer housing components 11, 12.

[0031] from Figure 1 As can be seen, the bottom cover 12 may have a generally shallow cavity 13, formed, for example, by pressing a sheet of metal. Other structures may also be used (e.g., molded from one or more parts), designed to fit into a generally plate-shaped "cover" 11 and house the printed circuit board 14 therein.

[0032] from Figure 1 As can also be seen, the cooling device / cover 11 is generally plate-shaped, preferably made of aluminum by extrusion, and has multiple longitudinally penetrating channels 17 along its entire length. Each channel 17 is separated by a wall, forming a square or rectangular cross-section, but other cross-sectional shapes, such as circular or hexagonal, may also be used. In the illustrated form, the multiple channel openings 17 do not extend through the entire end edge 20 of the plate, but instead leave channelless areas at the edges, where the receiving holes 21 of the fasteners 15 are located.

[0033] During manufacturing, the device 11 is first extruded into a flat plate and then cut to a suitable length to fit the bottom cover 12. Surface feature structures 18a / 18b may be formed / added to the surface of the plate 11 before, during, or after the cutting process. These feature structures preferably coincide / align with the location of one or more electronic components 19 on the printed circuit board 14. In the illustrated form, feature structure 18a can be formed by pressing a die into the surface. Figure 1The visible outer surface is formed by pressing out a shape 18b (rectangular in this embodiment), which protrudes from the opposite side of the device 11, such as... Figure 2 As shown. Through production control and the sidewall structure of each channel 17, collapse of channel 17 during the pressing process can be prevented.

[0034] Feature structures 18a / 18b are formed on the surface of the plate in areas overlapping with channels 17, such that during use, the coolant pumped / flowing through the channels also flows inside and / or behind the surface feature structures 18. Therefore, when the protrusion 18 contacts the electronic component 19, it is configured to dissipate / transfer the heat generated by the component through the coolant flowing inside the plate 11.

[0035] The cooling device 11 shown in the form of an embossed protrusion 18b on the lower side and an embossed recess 18a on the upper side of the board surface. In other forms, both the recess and the protrusion can be formed on the same side to accommodate components with a wider height range on the printed circuit board without changing other dimensions.

[0036] As previously described, the preferred method for forming the protrusion 18 is to press the surface (on one or both sides) with a pressing tool to deform the surface and the underlying channel 17 (while maintaining the integrity of the channel 17 to ensure unobstructed coolant flow). However, other methods may also be used, such as additive manufacturing or welding the protrusion into place. In practice, if the flat plate can contact multiple elements 19 of similar height (e.g., through a thermal interface material), the protruding or recessed surface feature is not necessarily necessary for the inventive concept.

[0037] In any case, it is recommended to apply a thermal interface material to either or both of the two mating surfaces to fill any minor gaps / defects that may exist when the plate 11 and the element 19 come into contact.

[0038] Figure 3 A step in the assembly process is shown, in which the formed plate 11 (e.g., through a thermal interface material) contacts the upper surface of the printed circuit board 14 housing the component 19. At this point, the lower surface of the printed circuit board 14 is visible, and the bottom cover 12 is not yet installed. Clearly, if the component 19 protrudes from both sides of the printed circuit board 14, a second plate 11 can be used as a "bottom cover". These two devices can each constitute the main walls of the printed circuit board housing and can be secured together by, for example, an outer frame accommodating the thickness of the printed circuit board, and / or by forming a cavity to accommodate the printed circuit board 14 using a pressing tool.

[0039] Figure 4The assembled housing 10 is shown, with the bottom cover 12 installed and aligned with the cooling unit 11, secured together by screws 15. Channel 17 is clearly visible, ready to connect to a manifold (not shown) that will supply coolant between a first end (e.g., the left edge 20 visible in the figure) and a second end (e.g., the right edge 22 not visible in the figure) of the cooling plate 11. The printed circuit board 14 is securely housed within the housing. Figure 4 It is not visible in the middle.

[0040] In summary, the overall embodiment of the present invention is a cooling plate, for example, a profile with an integrally formed channel manufactured by an extrusion molding process, and the cooling plate is used as a cover / cover for a printed circuit board housing. This structure enables a thinner housing design, while efficiently removing excess heat generated by the printed circuit board components through liquid cooling in the board channels. Specifically, surface feature structures (e.g., protrusions and / or recesses) aligned with the printed circuit board components can be formed on the plate, thereby accommodating differences in component height while maintaining the contact required for heat transfer.

[0041] In one specific embodiment, this disclosure provides a cooling device comprising an extruded aluminum profile having multiple longitudinally penetrating channels formed by an extrusion process. This device can be used as an outer wall / cover of a printed circuit board housing. The profile includes inwardly oriented protrusions, formed, for example, by creating recesses on an opposite surface, with the protrusions coinciding with the channels. This structure allows for contact with electronic components at different heights on the circuit board, and in use, coolant flowing through the channels behind the protrusions carries away heat generated by the electronic components on the printed circuit board.

Claims

1. A cooling device for cooling multiple electronic components mounted on a circuit board in an electronic control unit, the cooling device comprising: An extruded profile having at least one longitudinally penetrating channel between a first end edge and a second end edge for containing coolant; The extruded profile is configured to have a first side serving as the outer wall of the electronic control unit and a second side serving as an interface for cooling the plurality of electronic components mounted on the circuit board.

2. The cooling device according to claim 1, further comprising at least one feature structure protruding from and / or recessed into the surface of the profile, the feature structure coinciding with the at least one channel and configured to contact a corresponding electronic component of the circuit board.

3. The cooling device according to claim 2, wherein, The at least one feature structure is formed by creating a recess in either the first side or the second side, thereby forming a protrusion on the opposite side.

4. The cooling device according to any one of the preceding claims, wherein, Multiple channels are provided, and the multiple channels are located inside the side edge of the extruded profile.

5. The cooling device according to any one of the preceding claims, the cooling device comprising a thermal interface material applied to the second side of the profile.

6. A housing for a circuit board, wherein, The cooling device according to any one of the preceding claims constitutes a first wall of the housing, the first wall being configured to cooperate with a second wall or cover to form a housing for the circuit board.

7. The housing according to claim 6, wherein, The second wall or cover is made of pressed metal.

8. The housing according to claim 6 or 7, the housing further comprising a connection feature structure for aligning and joining the first wall and the second wall together, wherein the printed circuit board is mounted and housed between the two.

9. The housing according to any one of claims 5 to 8, wherein the housing further comprises the circuit board.

10. The housing according to any one of claims 5 to 9, the housing further comprising a thermal interface material for promoting thermal contact between the circuit board and the cooling device.

11. A method for manufacturing a cooling device, the method comprising the following steps: A longitudinally extruded profile, the profile including at least one channel or opening extending longitudinally through it; Cut a section of the extruded profile to form a generally plate-shaped component.

12. The method according to claim 11, wherein the method comprises the following steps: At least one feature structure is formed that protrudes from one side of the profile and / or is recessed into one side of the profile, the feature structure coinciding with the at least one channel.

13. The method according to claim 12, wherein, The at least one feature structure is formed by pressing a tool into one side of the profile, thereby forming a protrusion on the opposite side.

14. A method of manufacturing an electronic control unit, the method comprising: The method of manufacturing a cooling device according to claim 11 or 12 forms the first wall; The second wall is formed by pressing a thin sheet into a tray shape containing a cavity; The circuit board is assembled between the first wall and the second wall, so that it is housed in the cavity and forms thermal contact with the first wall on one side.

15. The method of claim 14, wherein the method comprises applying a thermal interface material between the mating surfaces of the circuit board and the first wall.

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