Cooling device

Abstract

A cooling device according to one aspect of the present disclosure comprises a thermal diffusion device and a cover member. The thermal diffusion device has a working fluid and a container in which the working fluid is disposed. The cover member covers one of a plurality of outer surfaces of the container. The cover member has a refrigerant inlet and a refrigerant outlet. The cooling device further comprises a plurality of fins positioned in an internal space formed by the thermal diffusion device and the cover member.

Description

Cooling device

[0001] The present disclosure relates to a cooling device. The present application claims priority based on Japanese Patent Application No. 2025-030164 filed in Japan on February 27, 2025, the content of which is incorporated herein by reference.

[0002] Conventionally, as a method for cooling a heating element such as a CPU (Central Processing Unit), a cooling method using a cooling member such as a cold plate is known. A flow path is formed inside the cold plate, and a coolant such as cold water flows through the flow path.

[0003] There is also a known technique in which a chamber that is a heat diffusion device (see, for example, Patent Document 1) is interposed between the heating element and the cold plate. The chamber transports heat from a high-temperature portion to a low-temperature portion by utilizing latent heat associated with the evaporation and condensation of the working fluid sealed inside. By interposing the chamber, the heat of the heating element can be spread in the planar direction and then transferred to the cold plate.

[0004] International Publication No. WO2011 / 145618

[0005] In the above-mentioned conventional technology, the cold plate and the chamber are configured as separate members, and the outer surface of the cold plate and the outer surface of the chamber are joined to each other. In this case, the joint portion has an increased thickness due to the two outer surfaces, which accordingly increases the thermal resistance. When the thermal resistance increases, the heat conduction efficiency from the chamber to the cold plate decreases, which may result in a decrease in cooling efficiency.

[0006] Therefore, realization of a cooling device with excellent cooling efficiency is expected.

[0007] The present disclosure provides a cooling device excellent in cooling efficiency.

[0008] A cooling device according to one aspect of the present disclosure includes a heat diffusion device and a cover member. The heat diffusion device has a working fluid and a container in which the working fluid is disposed. The cover member covers one outer surface among a plurality of outer surfaces of the container. The cover member has a coolant inlet and a coolant outlet. In the cooling device, a plurality of fins are located in an internal space formed by the heat diffusion device and the cover member.

[0009] The cooling device of this disclosure has excellent cooling efficiency.

[0010] Figure 1 is a schematic cross-sectional view of a cooling device according to an exemplary embodiment. Figure 2 is a schematic enlarged cross-sectional view of a heat diffusion device according to an exemplary embodiment. Figure 3 is a schematic plan view of a heat diffusion device according to an exemplary embodiment. Figure 4A is a schematic cross-sectional view of a heat diffusion device according to a first modified example of the exemplary embodiment. Figure 4B is a schematic cross-sectional view of a heat diffusion device according to a first modified example of the exemplary embodiment. Figure 5 is a schematic cross-sectional view of a cooling device according to a second modified example of the exemplary embodiment. Figure 6 is a schematic cross-sectional view of a cooling device according to a third modified example of the exemplary embodiment.

[0011] The following describes in detail, with reference to the drawings, embodiments for implementing the cooling device according to this disclosure (hereinafter referred to as "exemplary embodiments"). However, this disclosure is not limited by these exemplary embodiments. Furthermore, the exemplary embodiments can be combined as appropriate, provided that the processing content is not inconsistent. Also, the same parts are denoted by the same reference numerals in the following exemplary embodiments, and redundant descriptions are omitted.

[0012] Furthermore, in the drawings referenced below, for the sake of clarity, mutually orthogonal X, Y, and Z axis directions are sometimes defined, and a Cartesian coordinate system is shown with the positive Z axis pointing vertically upward.

[0013] (Exemplary Embodiments) First, the configuration of the cooling device 100 according to an exemplary embodiment will be described with reference to Figures 1 to 3. Figure 1 is a schematic cross-sectional view of the cooling device 100 according to an exemplary embodiment. Figure 2 is a schematic enlarged cross-sectional view of the heat diffusion device 10 according to an exemplary embodiment. Figure 3 is a schematic plan view of the heat diffusion device 10 according to an exemplary embodiment. In Figure 3, region R indicates the region where the wick 12 is provided.

[0014] As shown in Figure 1, the cooling device 100 comprises a heat diffusion device 10, a cover member 20, and a plurality of fins 30.

[0015] The heat diffusion device 10 is in thermal contact with the heat-generating element W, which is to be cooled. The heat diffusion device 10 is interposed between the heat-generating element W and the cover member 20, which will be described later. As shown in Figure 1, the heat diffusion device 10 may be in direct contact with the heat-generating element W, or it may be indirectly in contact via a heat transfer member such as a heat transfer sheet.

[0016] The heat diffusion device 10 includes a working fluid and a container 11 in which the working fluid is placed.

[0017] The working fluid is sealed inside the container 11. The working fluid may be, for example, water, hydrocarbon compounds, organic liquids (such as ethanol and methanol), or ammonia.

[0018] The container 11 extends horizontally (in the X-axis and Y-axis directions). The container 11 has an outer surface 11a that is in contact with the heating element W, an outer surface 11b located opposite to outer surface 11a, and an outer surface 11c that connects outer surfaces 11a and 11b. Outer surface 11b is an outer surface that is covered by the cover member 20. Outer surface 11b is an example of one outer surface. Outer surfaces 11a and 11b may be quadrilaterals in plan view. In other words, as shown in Figure 3, the container 11 may be quadrilateral in plan view from a direction perpendicular to outer surface 11a (in the Z-axis direction). In this case, there may be four outer surfaces 11c.

[0019] As shown in Figure 1, the outer surface 11c may have a projection 14 that protrudes outward from the container 11. The projection 14 may be located on the outer surface 11b side of the outer surface 11c and may extend along a direction parallel to the outer surface 11b. The upper surface of the projection 14 may be provided to be flush with the outer surface 11b.

[0020] As shown in Figure 1, the container 11 is hollow. A wick 12 is provided on the inner wall of the container 11. In Figure 1, the wick 12 is located along the entire inner wall of the container 11, but the wick 12 may be located in only a part of the inner wall of the container 11.

[0021] The container 11 may be made of a metal such as copper.

[0022] The cover member 20 is a box-shaped member that covers the outer surface 11b of the container 11. Specifically, the cover member 20 may have an outer surface 20a facing the outer surface 11b of the container 11, and a plurality of outer surfaces 20b connected to the outer surface 20a and extending in the direction toward the container 11 (negative Z-axis direction). The outer surfaces 20b are the sides of the cover member 20. The end faces of the outer surfaces 20b are joined to the upper surface of the protrusion 14 of the container 11. In the following description, the space formed by the heat diffusion device 10 and the cover member 20 will be referred to as the internal space S. The internal space S is the space enclosed by the outer surface 20a and outer surface 20b of the cover member 20, the outer surface 11b of the container 11, and the upper surface of the protrusion 14.

[0023] The cover member 20 may be made of a metal such as copper.

[0024] The cover member 20 has a refrigerant inlet 21 and an outlet (not shown). The inlet 21 is the inlet for the refrigerant to flow into the internal space S. The outlet is the outlet for the refrigerant to flow out of the internal space S. That is, the refrigerant that flows in from the inlet 21 passes through the internal space S and flows out from the outlet.

[0025] The inlet 21 and outlet are located on the outer surface 20a of the cover member 20. For example, the outer surface 20a of the cover member 20 has two openings that penetrate in the Z-axis direction. One end of a cylindrical member is inserted into each of these two openings. The other end of the cylindrical member protrudes from the cover member 20 in the positive Z-axis direction. The cooling device 100 has through holes in the cylindrical member as the inlet 21 and outlet, respectively.

[0026] The inlet 21 and outlet may be positioned overlapping in the direction of the fin arrangement (X-axis direction). Specifically, the inlet 21 and outlet may be located at the center of the outer surface 20a of the cover member 20 in the X-axis direction. The inlet 21 and outlet may be positioned with a gap between them in the direction in which the fin 30 extends (Y-axis direction).

[0027] As shown in Figure 1, the cover member 20 may have a protrusion 22 that projects toward the heat diffusion device 10 from its outer surface 20a, which is the surface facing the heat diffusion device 10.

[0028] The multiple fins 30 are located in the internal space S formed by the heat diffusion device 10 and the cover member 20. The multiple fins 30 are arranged with spacing between them in the X-axis direction. Each fin 30 is a plate-shaped member extending in the Y-axis direction and is arranged perpendicular to the outer surface 11b of the container 11. The refrigerant flows between two adjacent fins 30.

[0029] The fins 30 may be formed from a material with excellent thermal conductivity, such as metal.

[0030] A flow path 15 through which a refrigerant passes may be formed in the internal space S. The flow path 15 may have a first flow path 15a and a second flow path 15b. The first flow path 15a is positioned on the negative X-axis side relative to the plurality of fins 30 and extends in the Y-axis direction. The second flow path 15b is positioned on the positive X-axis side relative to the plurality of fins 30 and extends in the Y-axis direction. One of the first flow path 15a and the second flow path 15b may be connected to an inlet, and the other to an outlet.

[0031] In the cooling device 100 configured as described above, the heat from the heat-generating element W is transported to a location away from the heat-generating element W by utilizing the vaporization and liquefaction cycle of the working fluid sealed inside the heat diffusion device 10. By interposing the heat diffusion device 10 between the heat-generating element W and the fins 30, the heat from the heat-generating element W can be spread horizontally and then transferred to the fins 30. The refrigerant that passes through the inlet 21 and the flow path 15 in the internal space S and flows between two adjacent fins 30 exchanges heat with the heat-generating element W via the heat diffusion device 10, thereby cooling the heat-generating element W.

[0032] In conventional cooling systems, the cold plate and the chamber are constructed as separate components, with the outer surface of the cold plate and the outer surface of the chamber joined together. In this case, the thickness of the joint increases due to the two outer surfaces, and consequently, the thermal resistance increases. When the thermal resistance increases, the heat conduction efficiency from the chamber to the cold plate decreases, which could reduce the cooling efficiency of the cooling system. Furthermore, in conventional cooling systems, the chamber is interposed between the heat-generating element and the cold plate, which increases the thickness dimension between the cold plate and the chamber. Therefore, if a threshold range is set for the thickness dimension between the cold plate and the chamber, there was a risk that the thickness dimension would exceed the threshold.

[0033] On the other hand, in the exemplary embodiment of the cooling device 100, a cover member 20 is provided on the outer surface 11b of the heat diffusion device 10, and a plurality of fins 30 are provided between the cover member 20 and the heat diffusion device 10. In other words, the conventional cold plate and chamber are integrally constructed. This makes it possible to reduce the thickness dimension of the cooling device 100. Also, compared to the conventional case where the cold plate and chamber are separate components, the thickness of the joint portion can be reduced, resulting in superior heat conduction efficiency from the heat diffusion device 10 to the fins 30. Therefore, the cooling device 100 has excellent cooling efficiency.

[0034] As shown in Figure 1, the multiple fins 30 may be formed on the outer surface 11b of the container 11 of the heat diffusion device 10. In other words, the multiple fins 30 may be formed integrally with the heat diffusion device 10. The multiple fins 30 may extend from the outer surface 11b toward the cover member 20.

[0035] In this way, because the fins 30 are integrally formed with the heat diffusion device 10, heat from the heat diffusion device 10 can be transferred to the fins 30 more efficiently, resulting in superior cooling efficiency for the cooling device 100.

[0036] An intermediate material, such as a metal mesh made of copper or a silicone rubber sheet, may be interposed between the tip surface of the fin 30 and the protrusion 22 of the cover member 20.

[0037] As described above, the inlet 21 and outlet may be located on the outer surface 20a of the cover member 20.

[0038] With this configuration, the horizontal dimensions (in the X-axis and Y-axis directions) of the cooling device 100 can be reduced compared to the case where the refrigerant inlet and outlet are located on the outer surface 20b of the cover member 20.

[0039] As shown in Figure 2, the thickness t1 of the portion of the outer surface 11b of the container 11 where the multiple fins 30 are formed may be smaller than the thickness t2 of the other portions of the outer surface 11b.

[0040] With this configuration, compared to the case where thickness t1 and thickness t2 are the same, heat from the heat diffusion device 10 can be transferred to the fins 30 more efficiently, resulting in superior cooling efficiency for the cooling device 100.

[0041] The fins 30 may be, for example, skived fins. Skived fins are curved fins and are formed by skiving. Skiving is a processing method that forms fins by cutting and bending a plate-shaped substrate. In the cooling device 100 according to an exemplary embodiment, for example, by cutting and bending the outer surface 11b of the container 11 to form the fins 30, the thickness t1 of the portion where the fins 30 are formed can be made thinner than the thickness t2 of the other portion.

[0042] Because the fins 30 are skived fins, the thickness of each fin 30 can be reduced, allowing many fins 30 to be formed on the outer surface 11b of the container 11. As a result, the heat transfer area of ​​the fins 30 can be increased, improving the heat dissipation capacity of the fins 30. Therefore, the cooling device 100 has excellent cooling efficiency.

[0043] As shown in Figure 3, the multiple fins 30 may be located within the region R where the wick 12 is provided. That is, the multiple fins 30 may overlap with the wick 12 in a planar view of the heat diffusion device 10. Specifically, in a planar view of the heat diffusion device 10, the entirety of the multiple fins 30 may overlap with the wick 12.

[0044] As described above, since the plurality of fins 30 overlap the wick 12 to allow the heat spread in the horizontal direction by the heat diffusion device 10 to be sufficiently transferred to the fins 30, the cooling device 100 is excellent in cooling efficiency. Further, by expanding the range where the fins 30 are arranged, the height of each fin 30 can be suppressed, so that the dimension in the thickness direction of the cooling device 100 can be reduced.

[0045] As described above, in the cooling device 100 according to the exemplary embodiment, a cover member 20 is provided on an outer surface 11b of the heat diffusion device 10, and a plurality of fins 30 are provided between the cover member 20 and the heat diffusion device 10. This makes it possible to reduce the thickness of the joined portion compared to the conventional case where a cold plate and a chamber are separate members, so that the heat conduction efficiency from the heat diffusion device 10 to the fins 30 is excellent. Therefore, the cooling device 100 is excellent in cooling efficiency.

[0046] In the example of FIG. 1, an example in which the cover member 20 has a convex portion 22 is shown, but the cover member 20 does not necessarily have to have the convex portion 22.

[0047] Further, the position of the flow path 15 in the internal space S is not limited to the example shown in FIG. 1.

[0048] (First Modification) In the exemplary embodiment, an example is shown in which the container 11 has a shape having protruding portions 14 extending in the horizontal direction (the X-axis direction and the Y-axis direction), but the shape of the container 11 is not limited thereto. FIGS. 4A and 4B are schematic cross-sectional views of a heat diffusion device 10 according to a first modification of the exemplary embodiment.

[0049] As shown in FIG. 4A, the outer surface 11a of the container 11 may further have a convex portion 13 protruding in a direction away from the cover member 20 (negative Z-axis direction) with respect to the outer surface 11a. In this case, the region in the container 11 where the working fluid is arranged may also have a shape corresponding to the convex portion 13. That is, the inner wall corresponding to the outer surface 11a of the container 11 may have a concave portion 17 recessed in the direction away from the cover member 20.

[0050] This allows a large amount of working fluid to be stored in the recess 17. Furthermore, the protrusion 13 on the container 11 makes it easier to create a flat surface, thus improving positional accuracy relative to other components when placing it on other components.

[0051] Furthermore, as shown in Figure 4B, the container 11 may have a rectangular cross-sectional shape. In other words, the container 11 may have a rectangular prism shape. This can improve the strength of the container 11.

[0052] (Second Modification) In the exemplary embodiment, an example was shown in which the cover member 20 has an outer surface 20b which is a side surface, but the member having a side surface is not limited to this. Figure 5 is a schematic cross-sectional view of a cooling device 100 according to a second modification of the exemplary embodiment.

[0053] As shown in Figure 5, the heat diffusion device 10 may have a plurality of side surfaces 16 connected to the protrusion 14 and extending in the direction toward the cover member 20 (positive Z-axis direction). Such side surfaces 16 may be joined to the outer surface 20a of the cover member 20. That is, the internal space S may be formed by the outer surface 20a of the cover member 20, the outer surface 11b of the container 11, the protrusion 14, and the side surfaces 16.

[0054] Similarly, in this case, a cover member 20 is provided on the outer surface 11b of the heat diffusion device 10, and a plurality of fins 30 are provided between the cover member 20 and the heat diffusion device 10. As a result, the thickness of the joint can be reduced compared to the conventional case where the cold plate and the chamber are separate components, resulting in excellent heat conduction efficiency from the heat diffusion device 10 to the fins 30. Therefore, the cooling device 100 has excellent cooling efficiency.

[0055] (Third Modification) In the exemplary embodiment, an example was shown in which a plurality of fins 30 are integrally formed with the heat diffusion device 10, but the member on which the plurality of fins 30 are formed is not limited to this. Figure 6 is a schematic cross-sectional view of a cooling device 100 according to a third modification of the exemplary embodiment.

[0056] As shown in Figure 6, the plurality of fins 30 may be formed integrally with the cover member 20. The plurality of fins 30 may be formed on the protrusions 22 of the outer surface 20a of the cover member 20. The plurality of fins 30 may extend from the surface of the protrusion 22 facing the heat diffusion device 10 in a direction toward the heat diffusion device 10 (negative Z-axis direction).

[0057] Similarly, in this case, a cover member 20 is provided on the outer surface 11b of the heat diffusion device 10, and a plurality of fins 30 are provided between the cover member 20 and the heat diffusion device 10. As a result, the thickness of the joint can be reduced compared to the conventional case where the cold plate and the chamber are separate components, resulting in excellent heat conduction efficiency from the heat diffusion device 10 to the fins 30. Therefore, the cooling device 100 has excellent cooling efficiency.

[0058] As shown in Figure 6, the tip surfaces of multiple fins 30 may be in contact with the heat diffusion device 10. This allows heat from the heat diffusion device 10 to be transferred to the fins 30 more efficiently, resulting in superior cooling efficiency for the cooling device 100.

[0059] However, the tip surfaces of the multiple fins 30 do not necessarily have to be in contact with the heat diffusion device 10. In this case, an intermediate material such as a metal mesh made of copper or a silicone rubber sheet may be interposed between the tip surfaces of the fins 30 and the heat diffusion device 10.

[0060] Furthermore, this technology can also take the following configurations: (1) A cooling device comprising a heat diffusion device having a working fluid and a container in which the working fluid is disposed, and a cover member covering one of a plurality of outer surfaces of the container, wherein the cover member has a coolant inlet and outlet, and a plurality of fins are located in the internal space formed by the heat diffusion device and the cover member. (2) The cooling device according to (1), wherein the plurality of fins are formed on the one outer surface and extend from the one outer surface toward the cover member. (3) The cooling device according to (1) or (2), wherein the inlet and outlet are located on the surface of the cover member facing the heat diffusion device. (4) The cooling device according to (2), wherein the thickness of the portion of the one outer surface in which the plurality of fins are formed is smaller than the thickness of the other portion of the one outer surface. (5) The cooling device according to any one of (1) to (4), wherein the container has a protrusion projecting toward the cover member toward the outer surface opposite to the one outer surface. (6) The cooling device according to any one of (1) to (5), wherein the container has a wick on its inner wall, and the plurality of fins overlap with the wick in a planar perspective view.

[0061] The exemplary embodiments disclosed herein should be considered in all respects as illustrative and not restrictive. Indeed, the exemplary embodiments described above can be embodied in a variety of forms. Furthermore, the exemplary embodiments described above may be omitted, replaced, or modified in various ways without departing from the scope and spirit of the appended claims.

[0062] 10 Heat diffusion device 11 Container 12 Wick 13 Convex part 14 Projection part 15 Flow path 15a First flow path 15b Second flow path 16 Side surface 17 Recess 20 Cover member 21 Inlet 30 Fin 100 Cooling device S Internal space W Heating element

Claims

1. A cooling device comprising: a heat diffusion device having a working fluid and a container in which the working fluid is disposed; and a cover member covering one of a plurality of outer surfaces of the container, wherein the cover member has a coolant inlet and outlet, and a plurality of fins are located in the internal space formed by the heat diffusion device and the cover member.

2. The cooling device according to claim 1, wherein the plurality of fins are formed on the outer surface of the first and extend toward the cover member.

3. The cooling device according to claim 1, wherein the inlet and outlet are located on the surface of the cover member facing the heat diffusion device.

4. The cooling device according to claim 2, wherein the thickness of the portion on the outer surface in which the plurality of fins are formed is smaller than the thickness of the other portion on the outer surface.

5. The cooling device according to claim 1, wherein the container has a protrusion that projects in a direction away from the cover member relative to the outer surface located opposite to the first outer surface.

6. The cooling device according to claim 1, wherein the container has a wick on its inner wall, and the plurality of fins overlap with the wick in a planar perspective view.

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