Heat device

Abstract

To provide a heat device capable of improving the sealability.SOLUTION: The heat device according to this invention uses latent heat of a phase transformation material. The heat device in this embodiment includes a container, and a seal part, the container having a phase transformation region in which the phase transformation material is filled, and a communication path communicating the phase transformation region with the outside, the seal part serving for blocking the communication path, the container having an upper face, a lower face and a lateral face linking the upper face and the lower face, the communication path having an opening in the upper face, the phase transformation region having an internal space, the communication path having a through-hole whose cross section area is smaller near the seal part toward the opening.SELECTED DRAWING: Figure 9

Description

[Technical field]

[0001] The present disclosure relates to thermal devices. [Background technology]

[0002] Conventionally, thermal devices that utilize the latent heat of a phase-transforming material are known. For example, a vapor chamber, which is a type of thermal device, releases heat from a heat-generating component by transporting heat from a high-temperature part to a low-temperature part using the latent heat associated with the evaporation and condensation of a working fluid sealed inside (see Patent Document 1). [Prior art documents] [Patent documents]

[0003] [Patent Document 1] Japanese Utility Model Application Publication No. 54-42973 Summary of the Invention [Problem to be solved by the invention]

[0004] The present disclosure provides a thermal device that can improve sealing performance. [Means for solving the problem]

[0005] A thermal device according to one aspect of the present disclosure is a thermal device that utilizes latent heat of a phase change material. The thermal device according to the embodiment has a container and a sealing portion. The container has a phase change region in which a phase change material is sealed, and a communication passage that connects the phase change region to the outside. The sealing portion closes the communication passage. The container also has an upper surface, a lower surface, and a side surface that connects the upper surface and the lower surface. The communication passage has an opening on the upper surface. The phase change region has an internal space. The communication passage has a through hole in the vicinity of the sealing portion, the cross-sectional area of ​​which decreases toward the opening. Effect of the Invention

[0006] According to the present disclosure, it is possible to improve the sealing performance. [Brief description of the drawings]

[0007] [Figure 1] FIG. 1 is a perspective view of a heat dissipation device according to an embodiment. [Diagram 2] FIG. 2 is a view of the first member according to the embodiment as viewed in the positive direction of the Z axis from the negative direction of the Z axis. [Diagram 3] FIG. 3 is a view of the second member according to the embodiment as viewed in the negative direction of the Z axis from the positive direction of the Z axis. [Figure 4] FIG. 4 is a view of the intermediate member according to the embodiment, viewed from the Z-axis positive side toward the Z-axis negative side. [Diagram 5] 5 is a diagram in which the first groove formation region shown in FIG. 2 and the second groove formation region shown in FIG. 3 are superimposed on the intermediate member shown in FIG. [Figure 6] FIG. 6 is a diagram for explaining the flow of the working fluid in the heat dissipation device according to the embodiment. [Figure 7] FIG. 7 is a diagram for explaining the flow of the working fluid in the heat dissipation device according to the embodiment. [Figure 8] FIG. 8 is a schematic cross-sectional view showing an example of the configuration of the communication passage. [Figure 9] FIG. 9 is a schematic cross-sectional view showing the configuration of the sealing portion. [Figure 10] FIG. 10 is a diagram showing a schematic diagram of the force applied to the sealing portion when the pressure inside the heat dissipation device increases. [Figure 11] FIG. 11 is a schematic cross-sectional view showing another example of the configuration of the bonding layer. [Figure 12] FIG. 12 is a schematic cross-sectional view showing another example of the configuration of the bonding layer. [Figure 13] FIG. 13 is a schematic cross-sectional view showing another example of the configuration of the bonding layer. [Figure 14] FIG. 14 is a schematic cross-sectional view showing another example of the configuration of the bonding layer. [Figure 15] FIG. 15 is a schematic cross-sectional view showing another example of the configuration of the bonding layer. [Figure 16] FIG. 16 is a schematic cross-sectional view showing another example of the configuration of the bonding layer. [Figure 17] FIG. 17 is a schematic cross-sectional view showing another example of the configuration of the bonding layer. [Figure 18] FIG. 18 is a schematic cross-sectional view showing another example of the configuration of the bonding layer. [Figure 19] FIG. 19 is a schematic cross-sectional view showing another example of the configuration of the communication passage. [Figure 20] FIG. 20 is a diagram for explaining an example of the sealing step. [Figure 21] FIG. 21 is a diagram for explaining an example of the sealing step. [Figure 22] FIG. 22 is a diagram for explaining an example of the sealing step. [Figure 23] FIG. 23 is a diagram for explaining an example of the sealing step. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0008] Hereinafter, a form for carrying out a thermal device according to the present disclosure (hereinafter, referred to as an "embodiment") will be described in detail with reference to the drawings. Note that the present disclosure is not limited to this embodiment. In addition, each embodiment can be appropriately combined within a range that does not cause a contradiction in the processing contents. In addition, the same parts in each of the following embodiments are given the same reference numerals, and duplicated explanations will be omitted.

[0009] In addition, in the embodiments described below, expressions such as "constant", "orthogonal", "vertical" and "parallel" may be used, but these expressions do not necessarily mean "constant", "orthogonal", "vertical" and "parallel" strictly. In other words, each of the above expressions allows for deviations due to, for example, manufacturing accuracy and installation accuracy.

[0010] In addition, in order to make the explanation easier to understand, each of the drawings referred to below may show an orthogonal coordinate system that defines an X-axis direction, a Y-axis direction, and a Z-axis direction that are perpendicular to each other, and has the positive Z-axis direction as the vertically upward direction.

[0011] In the following, as an example of a thermal device according to the present disclosure, a heat dissipation device, specifically a vapor chamber, that efficiently transfers heat from a high temperature area to a low temperature area by utilizing the latent heat associated with the evaporation and condensation of a working fluid (an example of a phase-changing substance) will be described.

[0012] First, the overall configuration of a heat dissipation device according to an embodiment will be described with reference to Fig. 1. Fig. 1 is a perspective view of a heat dissipation device according to an embodiment.

[0013] As shown in FIG. 1, the heat dissipation device 1 has a ceramic container 2. The container 2 has a first member 10, a second member 20, and an intermediate member 30. The first member 10, the second member 20, and the intermediate member 30 are all plate-shaped, and are laminated so that the intermediate member 30 is sandwiched between the first member 10 and the second member 20. The container 2 is not limited to being made of ceramic. The material of the container 2 may be, for example, at least one selected from metal, ceramic, glass, and resin. In particular, the material of the container 2 is preferably at least one selected from ceramic, glass, and resin.

[0014] The container 2 has an operating region 100 and a frame region 200. The operating region 100 has an internal space, and a working liquid as a phase-changing substance is sealed in the internal space. As the working liquid, for example, water, a hydrocarbon compound, an organic liquid (e.g., ethanol, methanol, etc.), ammonia, or other liquids can be used.

[0015] The frame region 200 is a region surrounding the active region 100. In other words, the frame region 200 is a region of the heat dissipation device 1 that is outside the active region 100. The active region 100 is generally hollow, whereas the frame region 200 is generally solid.

[0016] The frame region 200 is a region that is intentionally formed wide to prevent, for example, working fluid or working fluid vapor from leaking from the interface between the first member 10 and the intermediate member 30 or the interface between the second member 20 and the intermediate member 30, or to prevent the outside atmosphere from entering the internal space of the operating region 100 from the above interfaces (i.e., to ensure airtightness).

[0017] The container 2 has a plurality of (here, two) communication passages 14, 15 that communicate the internal space of the operating region 100 with the outside. Of the communication passages 14, 15, for example, the communication passage 14 is used as a working fluid injection hole, and the communication passage 15 is used as a gas discharge hole. In this case, in the manufacturing process of the heat dissipation device 1, the working fluid is injected into the internal space of the operating region 100 from the communication passage 14, and accordingly, the gas present in the internal space of the operating region 100 is discharged to the outside through the communication passage 15. The communication passage 14 is located near one of the four corners of the first member 10, and the communication passage 15 is located near a corner diagonally opposite the communication passage 14.

[0018] It is not essential that the heat dissipation device 1 has a plurality of communication paths 14, 15. For example, the heat dissipation device 1 may have only one of the communication paths 14, 15.

[0019] The communication passages 14 and 15 are closed by the sealing portion 5. By closing the communication passages 14 and 15 by the sealing portion 5, the internal space of the heat dissipation device 1 is sealed and the working fluid is sealed in the working region 100. In this manner, the heat dissipation device 1 is a sealed container with a sealed interior.

[0020] The working fluid is filled at a ratio of, for example, 10% by volume or more and 95% by volume or less with respect to the total volume of the internal space of the operating region 100. Preferably, the ratio is 30% by volume or more and 75% by volume or less. More preferably, the ratio is 40% by volume or more and 65% by volume or less. The remaining part of the internal space of the operating region 100 other than the working fluid is in a vacuum state containing a part of the vaporized working fluid. This makes it possible to maintain gas-liquid equilibrium even in a high-temperature environment, making it difficult to dry out, and also allows efficient thermal diffusion even in a low-temperature environment, making it possible to increase thermal diffusivity in various temperature ranges.

[0021] The first member 10, the second member 20, and the intermediate member 30 are made of ceramics. Examples of ceramics that may be used to form the first member 10, the second member 20, and the intermediate member 30 include alumina (Al2O3), zirconia (ZrO2), silicon carbide (SiC), silicon nitride (Si3N4), aluminum nitride (AlN), cordierite (Mg2Al3(AlSi5O 18 )), silicon-impregnated silicon carbide (SiSiC), etc. Also, the ceramics constituting the first member 10, the second member 20, and the intermediate member 30 may be single crystal bodies.

[0022] Metallic heat dissipation devices are difficult to obtain rigidity due to the material and manufacturing method, and are difficult to thin. In addition, since the parts of metallic heat dissipation devices that come into contact with the working fluid are made of metal, there is room for improvement in terms of corrosion resistance. In contrast, the heat dissipation device 1 according to the embodiment is made of a first member 10, a second member 20, and an intermediate member 30 that are all made of ceramic, so that it is easier to thin the device compared to metallic heat dissipation devices and has excellent corrosion resistance.

[0023] 1, the heat dissipation device 1 is installed in a position in which the first member 10 faces upward, but the position of the heat dissipation device 1 is not limited to the example of FIG 1. For example, the heat dissipation device 1 may be installed in a position in which the first member 10 faces downward. Moreover, the heat dissipation device 1 may be installed vertically instead of horizontally as shown in FIG 1.

[0024] Since ceramics are a brittle material, an important issue for a heat dissipation device having a ceramic container is how to ensure durability against stresses generated by, for example, phase transformation of the working fluid.

[0025] Here, the vapor chamber described in Patent Document 1 has a communication passage in the operating area for injecting the working fluid. The thickness of the ceramic in the operating area is reduced by the amount of the internal space. For this reason, the vapor chamber described in Patent Document 1, in which the communication passage is provided in the operating area, is prone to lacking durability against stress, and there is a risk of cracks or the like occurring in the container. Furthermore, cracks occurring in the container may cause the working fluid sealed in the internal space to dry out, resulting in a deterioration in heat dissipation efficiency.

[0026] In contrast, in the heat dissipation device 1 according to the embodiment, the communication paths 14, 15 are located in the frame region 200. The frame region 200 is solid, unlike the operating region 100. By having the communication paths 14, 15 located in the frame region 200, durability can be improved compared to a case in which the communication paths 14, 15 are located in the operating region 100. In this way, the heat dissipation device 1 according to the embodiment can improve durability.

[0027] Furthermore, according to the heat dissipation device 1 of the embodiment, a larger effective space can be secured in the operating area 100 compared to when the communicating passages 14, 15 are located in the operating area 100, thereby improving the heat dissipation characteristics.

[0028] Moreover, since the frame region 200 in which the communication paths 14, 15 are located is made of the same ceramic material as the operating region 100, stress due to a difference in thermal expansion is unlikely to occur. Therefore, the heat dissipation device 1 according to the embodiment has high reliability.

[0029] Next, the configuration of the first member 10 will be described with reference to Fig. 2. Fig. 2 is a diagram of the first member 10 according to the embodiment, viewed in the positive direction of the Z axis from the negative direction of the Z axis.

[0030] Fig. 2 shows the lower surface of the first member 10, specifically, the surface (third surface) facing the upper surface (first surface) of the intermediate member 30. As shown in Fig. 2, the first member 10 has a lattice-shaped first groove portion 11 on the third surface.

[0031] The first groove portion 11 has a first recess 11a recessed into the third surface and a plurality of first protrusions 11b located within the first recess 11a. The first recess 11a is located in the center of the third surface, and has a rectangular outline in plan view. The first protrusions 11b are arranged in the vertical and horizontal directions at intervals within the first recess 11a. The first recess 11a and the first protrusions 11b form a lattice shape in the first groove portion 11.

[0032] Hereinafter, the area of ​​the third surface of the first member 10 where the first groove portion 11 is located will be referred to as the "first groove forming area 110." The first groove forming area 110 constitutes a part of the operating area 100. The first member 10 also has a rectangular frame-shaped first frame area 210 that surrounds the first groove forming area 110. The first frame area 210 constitutes a part of the frame area 200.

[0033] A plurality of (here, two) through holes 141a, 151a penetrating the first member 10 in the thickness direction (here, the Z-axis direction) are positioned in the first frame region 210. The through hole 141a constitutes a part of the first portion 141 of the communication passage 14, and the through hole 151a constitutes a part of the first portion 151 of the communication passage 15.

[0034] A heat source is disposed in the center of the upper surface (fifth surface) of the first member 10, which is located opposite the lower surface (third surface).

[0035] Next, the configuration of the second member 20 will be described with reference to Fig. 3. Fig. 3 is a diagram of the second member 20 according to the embodiment, viewed in the negative Z-axis direction from the positive Z-axis direction side.

[0036] Fig. 3 shows the upper surface of the second member 20, specifically, the surface (fourth surface) facing the lower surface (second surface) of the intermediate member 30. As shown in Fig. 3, the second member 20 has a lattice-shaped second groove portion 21 on the fourth surface.

[0037] The second groove portion 21 has a second recess 21a recessed into the fourth surface and a plurality of second protrusions 21b located within the second recess 21a. The second recess 21a is located in the center of the fourth surface, and has a rectangular outline in plan view. The plurality of second protrusions 21b are arranged in the vertical and horizontal directions at intervals within the second recess 21a. The second recess 21a and the plurality of second protrusions 21b form the second groove portion 21 in a lattice shape.

[0038] Hereinafter, the region of the fourth surface of the second member 20 where the second groove portion 21 is located will be referred to as the "second groove formation region 120." The second groove formation region 120 constitutes a part of the operating region 100. In addition, the second member 20 has a second frame region 220 in the shape of a rectangular frame that surrounds the second groove formation region 120. The second frame region 220 constitutes a part of the frame region 200.

[0039] The size of the second groove formation region 120 in the second member 20 is the same as the size of the first groove formation region 110 in the first member 10. In addition, the position of the second groove formation region 120 on the fourth surface of the second member 20 is the same as the position of the first groove formation region 110 on the third surface of the first member 10.

[0040] In this manner, by forming the first groove portion 11 and the second groove portion 21 in a lattice shape, it is possible to efficiently circulate the working fluid in the internal space of the heat dissipation device 1. Note that the first groove portion 11 and the second groove portion 21 do not necessarily need to be lattice-shaped.

[0041] In the second frame region 220, there are positioned a plurality of (here, two) recesses 141b, 151b recessed relative to the upper surface (fourth surface) of the second member 20. The recesses 141b form a part of the first portion 141 of the communication passage 14, and the recesses 151b form a part of the first portion 151 of the communication passage 15.

[0042] Further, grooves 142b and 152b are located in the second frame region 220. Groove 142b is a passage extending in a second direction (here, the Y-axis direction) intersecting with the extension direction (first direction, here the Z-axis direction) of first portion 141 of communication passage 14, with one end opening into recess 141b in first portion 141 and the other end opening into second groove-forming region 120. Groove 152b is a passage extending in a second direction (here, the Y-axis direction) intersecting with the extension direction (first direction, here the Z-axis direction) of first portion 151 of communication passage 15, with one end opening into recess 151b in first portion 151 and the other end opening into second groove-forming region 120.

[0043] Next, the configuration of the intermediate member 30 will be described with reference to Fig. 4. Fig. 4 is a diagram of the intermediate member 30 according to the embodiment, viewed in the Z-axis negative direction from the Z-axis positive direction side.

[0044] As shown in Fig. 4, the intermediate member 30 has a third frame region 230 having a rectangular frame shape. The third frame region 230 constitutes a part of the frame region 200. The intermediate member 30 also has a central portion 32 that is circular in plan view and located inside the third frame region 230, and a plurality of connecting portions 33 that are located between the central portion 32 and the third frame region 230 and connect the central portion 32 and the third frame region 230. In the example shown in Fig. 4, the central portion 32 is located at the center of the intermediate member 30. The multiple connecting portions 33 extend radially from the central portion 32 toward the third frame region 230 at intervals from one another while increasing in width.

[0045] The intermediate member 30 further has a plurality of steam holes 36 and a plurality of reflux holes 37. The plurality of steam holes 36 and the plurality of reflux holes 37 each penetrate the upper surface (first surface) and the lower surface (second surface) of the intermediate member 30.

[0046] The multiple steam holes 36 function as part of a flow path for vapor of the working fluid. The multiple steam holes 36 are located between two adjacent connection parts 33. That is, the multiple steam holes 36 and the multiple connection parts 33 are located alternately in the circumferential direction. Like the multiple connection parts 33, the multiple steam holes 36 are spaced apart from one another and extend radially from the central part 32 toward the third frame region 230 while increasing in width.

[0047] The multiple reflux holes 37 function as part of a flow path for the working fluid. The reflux holes 37 are fine holes having a smaller opening area than the above-mentioned steam holes 36. Specifically, the reflux holes 37 are small enough to generate capillary action in the working fluid passing through the reflux holes 37.

[0048] A plurality of (here, two) through holes 141c, 151c penetrating the intermediate member 30 in the thickness direction (here, the Z-axis direction) are positioned in the third frame region 230. The through hole 141c constitutes a part of the first portion 141 of the communication passage 14, and the through hole 151c constitutes a part of the first portion 151 of the communication passage 15.

[0049] Fig. 5 is a diagram in which the first groove forming region 110 shown in Fig. 2 and the second groove forming region 120 shown in Fig. 3 are superimposed on the intermediate member 30 shown in Fig. 4. Note that, in Fig. 5, the communication passages 14 and 15 are omitted for ease of understanding.

[0050] 5, the first groove formation region 110 and the second groove formation region 120 overlap with the third frame region 230 of the intermediate member 30. In other words, the first groove formation region 110 and the second groove formation region 120 extend outward from a region in the intermediate member 30 where the multiple steam holes 36 and the multiple reflux holes 37 are formed (hereinafter referred to as the "hole formation region").

[0051] In this way, by making the first groove formation region 110 of the first member 10 and the second groove formation region 120 of the second member 20 wider than the hole formation region of the intermediate member 30, the internal space of the heat dissipation device 1 can be expanded outward compared to when the first groove formation region 110 and the second groove formation region 120 are made approximately the same as the hole formation region.

[0052] The heat source is disposed in the center of the heat dissipation device 1. Therefore, the temperature of the heat dissipation device 1 decreases the farther it is from the heat source, i.e., the closer it is to the outer periphery of the heat dissipation device 1. Also, the vapor of the working fluid condenses into liquid as it moves to the low-temperature region. Therefore, by expanding the internal space of the heat dissipation device 1 outward, condensation of the working fluid occurs more easily. This makes it possible to make it difficult for dry-out to occur.

[0053] Note that, while an example has been shown here in which the first groove formation region 110 and the second groove formation region 120 extend outward from the hole formation region of the intermediate member 30, this is not limiting, and the hole formation region of the intermediate member 30 may extend outward from the first groove formation region 110 and the second groove formation region 120.

[0054] The operating region 100 of the heat dissipation device 1 has an internal space sandwiched between a first groove forming region 110 and a second groove forming region 120, and a working fluid is sealed in the internal space. In addition, an intermediate member 30 is interposed between the first groove forming region 110 and the second groove forming region 120 in the internal space, and thus the operating region 100 is partitioned into a first space sandwiched between the first groove forming region 110 and the intermediate member 30, and a second space sandwiched between the second groove forming region 120 and the intermediate member 30. The first space and the second space are connected by a steam hole 36 and a reflux hole 37 formed in the intermediate member 30.

[0055] Next, the flow of the working fluid in the heat dissipation device 1 according to the embodiment will be described with reference to Fig. 6 and Fig. 7. Fig. 6 and Fig. 7 are diagrams for explaining the flow of the working fluid in the heat dissipation device 1 according to the embodiment. Note that Fig. 6 is a diagram in which the third frame region 230 is omitted from the diagram shown in Fig. 5, and Fig. 7 is a cross-sectional view taken along line VII-VII in Fig. 6. In Fig. 6 and Fig. 7, the flow of steam is indicated by open arrows, and the flow of liquid is indicated by filled arrows.

[0056] The working fluid is heated by the heat source and vaporized into steam. As described above, the heat source is disposed in the center of the upper surface (fifth surface) of the first member 10 (see Figs. 1 and 2). Therefore, the vapor of the working fluid is generated in the center of the first space (the space sandwiched between the first member 10 and the intermediate member 30).

[0057] The vapor of the working fluid passes through the first groove portion 11 of the first groove formation region 110, diffuses in the in-plane direction (XY plane direction) of the heat dissipation device 1 (see the open arrows in Figure 6), and moves through the multiple steam holes 36 to the second space (the space sandwiched between the second member 20 and the intermediate member 30) (see the open arrows in Figure 7).

[0058] The vapor that has moved to the second space is condensed and liquefied due to a drop in temperature. The liquefied working fluid moves through the second groove formation region 120 toward the center of the heat dissipation device 1 due to the capillary force of the second groove portion 21 (see the black arrow in FIG. 6). During this process, the working fluid enters the return hole 37 and is returned to the first space by the capillary force of the return hole 37 (see the black arrow in FIG. 7). By repeating the above cycle, the heat dissipation device 1 can transfer heat from the heat source.

[0059] Next, the configuration of the communication passages 14 and 15 will be described with reference to Fig. 8. Fig. 8 is a schematic cross-sectional view showing an example of the configuration of the communication passage 14. Although Fig. 8 shows the communication passage 14 as an example, the communication passage 15 has a similar configuration to the communication passage 14.

[0060] 8, the communication passage 14 connects the internal space of the operating region 100 with the outside. The communication passage 14 has a first portion 141 that extends in the thickness direction of the container 2 (here, the Z-axis direction) and opens to the outside, and a second portion 142 that extends in the surface direction of the container 2 (here, the Y-axis direction) and opens to the internal space of the operating region 100.

[0061] The first portion 141 is formed by the through hole 141a of the first member 10, the recess 141b of the second member 20, and the through hole 141c of the intermediate member 30. The second portion 142 is formed by the groove portion 142b of the second member 20 and the lower surface 302 (second surface) of the intermediate member 30. Note that, although an example in which the recess 141b of the communication passage 14 is recessed further than the groove portion 142b of the second portion 142 is shown in FIG. 8, the recess 141b and the groove portion 142b may be flush with each other.

[0062] Thus, the communication path 14 has a first portion 141 extending in a first direction (here, the Z-axis direction) and a second portion 142 extending in a direction intersecting the first direction (here, the Y-axis direction). In other words, the communication path 14 is bent. Therefore, according to the heat dissipation device 1 according to the embodiment, even if high pressure occurs in the operating region 100, high pressure is unlikely to be applied to the sealing portion 5, and therefore reliability is high.

[0063] The first portion 141 is open on the upper surface of the first member 10 and extends across the first and second spaces of the operating region 100 in the frame region 200. The second portion 142 is located on the second space side of the operating region 100 in the frame region 200.

[0064] In the heat dissipation device 1, the first space side of the first and second spaces is under high pressure. In other words, the second space side of the first and second spaces is under relatively low pressure. Therefore, by positioning the second portion 142 on the second space side, it is possible to prevent high pressure from being applied to the communication passage 14.

[0065] 1, the communication passage 14 is positioned so as to sandwich the operating region 100 between itself and the communication passage 15. By arranging the two communication passages 14, 15 in this manner, it is possible to prevent a local decrease in durability compared to, for example, a case in which the two communication passages 14, 15 are arranged side by side.

[0066] In the first portion 141 of the communication passage 14, the through hole 141a corresponds to a first passage that opens to the outside, and the through hole 141c corresponds to a second passage that is continuous with the through hole 141a and has a smaller diameter than the first passage.

[0067] Next, a description will be given of the configuration of the sealing portion 5. Fig. 9 is a schematic cross-sectional view showing the configuration of the sealing portion 5. As shown in Fig. 9, the sealing portion 5 has a shielding plate 51 and a bonding layer 52.

[0068] The shielding plate 51 is, for example, a plate-shaped member, and is located on a container made up of the first member 10, the second member 20, and the intermediate member 30. Specifically, the shielding plate 51 is located on the upper surface (fifth surface) of the first member 10. The shielding plate 51 shields the opening of the communication passage 14 on the outside side.

[0069] The bonding layer 52 is located on the first member 10 so as to surround the entire periphery of the opening of the communication passage 14 on the outside side, and bonds the first member 10 and the shielding plate 51 together.

[0070] In this way, the sealing portion 5 fills the gap between the shielding plate 51 that shields the communication passage 14 and the first member 10 with the bonding layer 52 made of resin. With this configuration, it is possible to preferably ensure airtightness against pressure changes. This point will be described with reference to Fig. 10. Fig. 10 is a diagram that shows a schematic view of the force applied to the sealing portion 5 when the pressure inside the heat dissipation device 1 increases.

[0071] As described above, the heat dissipation device 1 according to the embodiment has a working fluid, and transfers heat from a heat source by utilizing the cycle of evaporation and condensation of the working fluid. Here, when no heat source is disposed, the internal space of the heat dissipation device 1 is in a vacuum state. On the other hand, when a heat source is disposed in the heat dissipation device 1 and the working fluid evaporates, the internal space of the heat dissipation device 1 is in a pressurized state. In this way, the pressure in the internal space of the heat dissipation device 1 changes as the working fluid changes state from liquid to gas or gas to liquid in response to a temperature change. As an example, the pressure in the internal space changes to 1 atmosphere at 100°C, 5 atmospheres at 150°C, and 15 atmospheres at 200°C.

[0072] As shown in FIG. 10, the pressure in the operating region 100 of the heat dissipation device 1 is transmitted to the shielding plate 51 that shields the communication passage 14. The shielding plate 51 then tries to deform in response to the pressure change. Since the shielding plate 51 is bonded to the first member 10 via the bonding layer 52, at least the portion of the shielding plate 51 that faces the opening of the communication passage 14 deforms minutely in response to the pressure change. This minute deformation suppresses the deformation of the bonding layer 52 made of resin, so that the sealing state by the bonding layer 52 is easily maintained even if the pressure in the internal space of the heat dissipation device 1 changes. Therefore, according to the heat dissipation device 1 according to the embodiment, it is possible to preferably ensure the hermeticity against the pressure change in the internal space.

[0073] If the shielding plate 51 does not deform minutely in response to a pressure change in the internal space, the bonding layer 52 will deform significantly instead. In this case, a gap may be generated between the shielding plate 51 and the first member 10 or the bonding layer 52 may be damaged, which may cause the sealing state provided by the bonding layer 52 to be released. The same applies when the communicating passage 14 is blocked only by the bonding layer 52, and the bonding layer 52 may deform significantly due to a pressure change in the internal space, causing the bonding layer 52 to be damaged.

[0074] Furthermore, ceramics have a lower thermal conductivity than metals. Therefore, when the container 2 is made of ceramics, heat is transferred to the resin bonding layer 52 relatively slowly. In other words, the temperature change of the resin bonding layer 52 is gradual. This makes it difficult for the bonding layer 52 to peel off from the container. In other words, the hermeticity of the heat dissipation device 1 is maintained for a long period of time.

[0075] Furthermore, a part of the bonding layer 52 (in the embodiment, a second bonding layer 522 described later) may be located on the side of the shielding plate 51 and may be in contact with the side of the shielding plate 51. When the shielding plate 51 is pressed in the direction indicated by the upward arrow in Fig. 10 by the pressure in the internal space, the side of the shielding plate 51 deforms in the direction indicated by the horizontal arrow in Fig. 10. In contrast, the bonding layer 52 made of resin is easily elastically deformed and can flexibly deform following the shielding plate 51. Therefore, even if pressure changes in the internal space of the heat dissipation device 1 are repeated, the airtightness of the internal space of the heat dissipation device 1 is easily ensured.

[0076] Returning to FIG. 9 . The bonding layer 52 according to the embodiment may have a first bonding layer 521 and a second bonding layer 522. The first bonding layer 521 is located between the shielding plate 51 and the first member 10, and is in contact with the surface 51a of the shielding plate 51 facing the first member 10. The first bonding layer 521 is located so as to surround the entire periphery of the communication passage 14. The second bonding layer 522 is located on the side of the shielding plate 51, and is in contact with the side surface 51b of the shielding plate 51. Similarly to the first bonding layer 521, the second bonding layer 522 is also located so as to surround the entire periphery of the communication passage 14. In this way, by having the first bonding layer 521 between the shielding plate 51 and the first member 10, the sealing performance can be further improved.

[0077] The first bonding layer 521 and the second bonding layer 522 may be made of different types of resin. In this case, the first bonding layer 521 may be made of an ultraviolet curing resin. With this configuration, the sealing step, which is one step in the manufacturing method of the heat dissipation device 1, can be simplified. This point will be described later.

[0078] Examples of the ultraviolet curing resin include urethane acrylate, acrylic resin acrylate, epoxy acrylate, and unsaturated polyester resin. When the first bonding layer 521 is made of an ultraviolet curing resin, it is preferable that ceramic that transmits ultraviolet light is used for the shielding plate 51. Examples of such ceramic include alumina and sapphire.

[0079] The shielding plate 51 may be made of ceramic, metal, resin, or a composite of two or more of these. In addition, the shielding plate 51 is preferably made of ceramic, resin, or a composite of ceramic and resin.

[0080] Further, a resin other than the ultraviolet curing resin may be used for the second bonding layer 522. For example, the second bonding layer 522 may be any one of epoxy resin, silicon resin, and acrylic resin. Among these, epoxy resin is preferable as the material for the second bonding layer 522 because it has superior heat resistance, pressure resistance, and water resistance compared to other resins.

[0081] Fig. 11 is a schematic cross-sectional view showing another example of the configuration of the bonding layer 52. As shown in Fig. 11, the first bonding layer 521 may be exposed to a side of the shielding plate 51 from between the shielding plate 51 and the first member 10. In this case, the second bonding layer 522 may cover the side surface 51b of the shielding plate 51 and also cover the portion of the first bonding layer 521 exposed between the shielding plate 51 and the first member 10.

[0082] 12 and 13 are schematic cross-sectional views showing another example of the configuration of the bonding layer 52. As shown in Fig. 12 and 13, the first bonding layer 521 may be located on the opposing surface 51a and the side surface 51b of the shielding plate 51.

[0083] 12, the second bonding layer 522 may also be located on the side surface 51b of the shielding plate 51. That is, both the first bonding layer 521 and the second bonding layer 522 may be in contact with the side surface 51b of the shielding plate 51.

[0084] 13, the second bonding layer 522 may be in contact with the first bonding layer 521 without being in contact with the side surface 51b of the shielding plate 51. In other words, only the first bonding layer 521 may be in contact with the side surface 51b of the shielding plate 51.

[0085] 14 and 15 are schematic cross-sectional views showing another example of the configuration of the bonding layer 52. As shown in Fig. 14, the second bonding layer 522 may further cover a part of the exposed surface 51c, which is the surface opposite to the opposing surface 51a of the shielding plate 51. By covering not only the opposing surface 51a of the shielding plate 51 but also a part of the exposed surface 51c with the bonding layer 52, it is possible to further improve the sealing performance against pressure changes.

[0086] 15, the second bonding layer 522 may cover the entire exposed surface 51c instead of just a part of it, thereby making it possible to further improve the sealing performance against pressure changes.

[0087] 16 to 18 are schematic cross-sectional views showing another example of the configuration of the bonding layer 52. As shown in Fig. 16 to 18, the bonding layer 52 may be made of one type of resin. In this case, the bonding layer 52 may be made of, for example, an ultraviolet curing resin.

[0088] 16, the bonding layer 52 may be in contact with an opposing surface 51a of the shielding plate 51 and the first member 10. Also, as shown in Fig. 17, the bonding layer 52 may be in contact with a side surface 51b of the shielding plate 51 and the first member 10. In this case, the opposing surface 51a of the shielding plate 51 may be in contact with the first member 10.

[0089] 18, the bonding layer 52 may be located on both the opposing surface 51a and the side surface 51b of the shielding plate 51. In this manner, the bonding layer 52 may be made of one type of resin.

[0090] Fig. 19 is a schematic cross-sectional view showing another example of the configuration of the communication passage 14. As shown in Fig. 19, the communication passage 14 may be located in the operating region 100. In this case, the communication passage 14 may consist of only a portion corresponding to the above-mentioned through hole 141a (see, for example, Fig. 8).

[0091] Next, an example of a manufacturing method of the heat dissipation device 1 according to the embodiment will be described. First, green sheets are formed by a doctor blade method, a roll compaction method, or the like using raw materials of the first member 10, the second member 20, and the intermediate member 30, and a laminate is obtained by stacking a plurality of green sheets.

[0092] Next, the obtained laminate is subjected to laser processing or die punching to obtain each of the molded bodies of the first member 10, the second member 20, and the intermediate member 30. For example, by performing laser processing on the laminate, a molded body of the intermediate member 30 in which the through holes 141c, 151c, the plurality of steam holes 36, and the plurality of reflux holes 37 are formed can be obtained. In addition, by performing laser processing on the obtained laminate, a molded body of the first member 10 in which the through holes 141a, 151a and the first groove formation region 110 are formed can be obtained. In addition, by performing laser processing on the obtained laminate, a molded body of the second member 20 in which the recesses 141b, 151b, the grooves 142b, 152b, and the second groove formation region 120 are formed can be obtained.

[0093] Next, the respective compacts of the first member 10, the second member 20 and the intermediate member 30 are stacked in the order of the second member 20, the intermediate member 30 and the first member 10 and fired to obtain a sintered body of the container 2 in which the first member 10, the second member 20 and the intermediate member 30 are integrated. In this manner, the first member 10, the second member 20 and the intermediate member 30 are integrally formed. Therefore, since no adhesive or the like is required, a highly reliable heat dissipation device 1 can be obtained.

[0094] The method for obtaining each of the molded bodies of the first member 10, the second member 20, and the intermediate member 30 is not limited to the above-mentioned method, and may be, for example, a method in which each of the molded bodies is obtained by processing green sheets and then laminating the green sheets. In the above-mentioned example, the molded body of the container 2 is obtained by producing each of the molded bodies of the first member 10, the second member 20, and the intermediate member 30 individually and then laminating them, but the molded body of the container 2 may be obtained by, for example, sequentially laminating processed green sheets.

[0095] Next, the working fluid is injected into the sintered body, for example, from one of the communication passages 14, 15. The gas present inside the sintered body is discharged to the outside from the other of the communication passages 14, 15 as the working fluid is injected.

[0096] Next, a pressure reducing device such as a vacuum pump is used to evacuate the inside of the sintered body through the communication passages 14, 15. Note that while it is desirable for the inside of the sintered body to be in a vacuum state, it is not necessary for the inside of the sintered body to be in a strict vacuum state, and for example, a reduced pressure state close to a vacuum state may be acceptable.

[0097] Next, with the inside of the sintered body being evacuated to a vacuum, the communicating paths 14, 15 are sealed. An example of this sealing step will be described with reference to Figs. 20 to 23. Figs. 20 to 23 are views for explaining an example of the sealing step. Here, an example of the sealing step will be described in which the bonding layer 52 has a first bonding layer 521 made of an ultraviolet curing resin and a second bonding layer 522 made of an epoxy resin.

[0098] 20, ultraviolet curing resin 521X is applied to the upper surface (fifth surface) of the first member 10. The ultraviolet curing resin 521X is applied in a circumferential shape so as to surround the opening of the communication passage 14.

[0099] 21, a shielding plate 51 is placed on the ultraviolet curing resin 521X so as to shield the communication passage 14. When the ultraviolet curing resin 521X is used, it is preferable to use a shielding plate 51 made of a material that transmits ultraviolet light. As such a shielding plate 51, for example, a thin plate made of a ceramic such as alumina or sapphire can be used.

[0100] 22, ultraviolet rays R are applied from above the shielding plate 51. As a result, the ultraviolet curing resin 521X is cured by the ultraviolet rays R to become the first bonding layer 521. In addition, the shielding plate 51 and the first member 10 are bonded by the first bonding layer 521, and the internal space (operating region 100) of the container 2 consisting of the first member 10, the second member 20, and the intermediate member 30 is sealed.

[0101] 23, a second bonding layer 522 made of epoxy resin is applied to the surface of the first member 10. Specifically, the second bonding layer 522 is applied circumferentially so as to cover the side surface 51b of the shielding plate 51. The epoxy resin hardens, for example, over time. This further securely seals the internal space (operating region 100) of the container 2. In this manner, the heat dissipation device 1 is obtained.

[0102] (Example) A heat dissipation device was manufactured by the above-mentioned manufacturing method using alumina for the first member, the second member, the third member, and the shielding plate, ultraviolet curing resin for the first bonding layer, and epoxy resin for the second bonding layer. The dimensions of the manufactured heat dissipation device (hereinafter, referred to as "heat dissipation device according to the embodiment") are as follows. External dimensions (width x length x thickness): 50mm x 50mm x 0.5mm Width of the frame area located outside the groove formation area: 10 mm Opening diameter of connecting passage: 1.7mm External dimensions of shielding plate (width x length x thickness): 8mm x 8mm x 0.2mm Thickness of the first bonding layer: 0.1 mm Thickness of the second bonding layer: 1mm

[0103] Then, a test was conducted on the airtightness of the heat dissipation device according to the embodiment. Specifically, the heat dissipation device according to the embodiment was left in a vacuum for a predetermined time (several days), and the presence or absence of a change in weight before and after the time was confirmed. As a result, no change in weight was observed in the heat dissipation device according to the embodiment before and after the device was left in a vacuum. This means that the working fluid located in the internal space of the heat dissipation device did not leak out to the outside of the heat dissipation device. From this result, it was confirmed that the airtightness of the heat dissipation device according to the embodiment was ensured.

[0104] In the above-described embodiment, the through holes 141a, 151a are described as having a tapered shape, but the shape of the through holes 141a, 151a is not limited to a tapered shape. For example, the shape of the through holes 141a, 151a may be a straight shape with a substantially constant diameter.

[0105] As described above, the thermal device according to the embodiment (for example, the heat dissipation device 1) is a thermal device that utilizes the latent heat of a phase-change material (for example, a working fluid). The thermal device according to the embodiment has a container (for example, the container 2) and a sealing part (for example, the sealing part 5). The container has a phase change region (for example, the operating region 100) in which a phase-change material is sealed, and a communication passage (for example, the communication passages 14, 15) that connects the phase change region to the outside. The sealing part blocks the communication passage. In addition, the sealing part has a shielding plate (for example, the shielding plate 51) and a bonding layer (for example, the bonding layer 52). The shielding plate is made of ceramic, metal, or a composite containing two or more of these and resin, which is located on the container and shields the communication passage. The bonding layer is made of resin, which is located on the container so as to surround the entire periphery of the communication passage, and bonds the container and the shielding plate.

[0106] Therefore, according to the sealed container according to the embodiment, it is possible to improve the sealing performance.

[0107] The thermal device according to the present disclosure is not limited to a heat dissipation device. For example, the thermal device according to the present disclosure may be a heat storage device that stores latent heat accompanying a phase transformation of a heat storage material (an example of a phase change material) as thermal energy. In this case, the heat storage material used may be one that undergoes a solid-liquid phase transformation or a solid-solid phase transformation. In this way, the phase change material does not necessarily have to undergo a gas-liquid phase transformation. In other words, the phase change material does not necessarily have to be a liquid, and may be a solid.

[0108] The embodiments disclosed herein should be considered to be illustrative and not restrictive in all respects. Indeed, the above-described embodiments may be embodied in various forms. In addition, the above-described embodiments may be omitted, substituted, or modified in various forms without departing from the scope and spirit of the appended claims. [Explanation of symbols]

[0109] 1. Heat dissipation devices 5 Sealing part 10 First member 11 First groove 11a First recess 11b First protrusion 14,15 Communication path 20 Second member 21 Second groove 21a Second recess 21b Second protrusion 30 Intermediate parts 36 Steam Vent 37 Reflux hole 51 Shielding plate 52 Bonding layer 100 Operating Range 141 Part 1 141a Through hole 141b Recess 141c through hole 142 Part 2 200 frame area

Claims

1. A thermal device utilizing latent heat of a phase change material, a container having a phase change region in which the phase change material is sealed and a communication passage connecting the phase change region to the outside; a sealing portion that closes the communication passage; having The container has an upper surface, a lower surface, and a side surface connecting the upper surface and the lower surface, The communication passage has an opening on the upper surface, The phase transformation region has an internal space, The thermal device, wherein the communication path has a through hole whose cross-sectional area decreases toward the opening in the vicinity of the sealing portion.

2. The thermal device according to claim 1 , wherein the communication passage has a recess located on the lower surface side of the through hole.

3. The sealing portion is a shielding plate made of ceramic, resin, or a composite of ceramic and resin, the shielding plate being positioned above the container and shielding the opening of the communication passage facing the outside; a bonding layer made of resin that is located on the container so as to surround the entire periphery of the opening and bonds the container and the shielding plate; having A portion of the bonding layer is located on a side of the shielding plate and is in contact with a side surface of the shielding plate. The thermal device according to claim 1 or 2.

4. The bonding layer is a first bonding layer located between the shielding plate and the container and in contact with a surface of the shielding plate facing the container; a second bonding layer located on a side of the shielding plate and in contact with a side surface of the shielding plate; The thermal device of claim 3 , comprising:

5. The bonding layer is a first bonding layer located between the shielding plate and the container and to the side of the shielding plate, in contact with a surface of the shielding plate facing the container and a side surface of the shielding plate; a second bonding layer covering a portion of the first bonding layer exposed from the shielding plate; The thermal device according to claim 3 or 4, comprising:

6. The thermal device according to claim 4 , wherein the second bonding layer covers a surface of the shielding plate opposite to the opposing surface.

7. The thermal device according to any one of claims 1 to 6, wherein the container is made of ceramic.

8. The thermal device according to any one of claims 1 to 7, wherein a liquid is located in the internal space.

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