Heat transfer element

Abstract

To provide a heat transfer element capable of smoothly recovering working fluid condensed in a heat exchange section by using a wick in a storage chamber.SOLUTION: A heat transfer element includes: a heat exchange section extending in a first direction; and a vapor chamber connected to one end part of the heat exchange section and having a contact surface coming into contact with a heating element. The vapor chamber includes: a first container that communicates with the internal space of the heat exchange section and forms a storage chamber for storing working fluid; and a first wick disposed within the storage chamber and capable of holding the working fluid. The heat exchange section has a second container that forms the internal space. In the second container, a container projecting part projecting toward the first wick within the storage chamber is provided in a part in the circumferential direction about a central axis of the second container.SELECTED DRAWING: Figure 1

Description

Technical Field

[0001] The present invention relates to a heat transport element.

Background Art

[0002] Patent Document 1 discloses a cooler including a heat receiving portion on which a heating element such as an electronic component is mounted, a heat pipe joined to the heat receiving portion and having a working fluid accommodated therein, and heat radiation fins provided on the surface of the heat pipe. In this cooler, when heat of the heating element is transmitted to the heat pipe through the heat receiving portion and the working fluid in the heat pipe is heated to a saturation temperature or higher, the working fluid vaporizes. The vaporized working fluid is condensed by radiating heat to the outside through the heat pipe and the heat radiation fins.

Prior Art Documents

Patent Documents

[0003]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0004] By the way, a storage chamber that communicates with the internal space of a heat exchange portion (such as a heat pipe) and stores a working fluid may be provided in the heat receiving portion. Further, when a wick capable of capturing and holding the working fluid by capillary force is provided in the storage chamber, it is desirable to smoothly recover the working fluid condensed in the heat exchange portion with the wick in the storage chamber. However, due to the surface tension of the working fluid or the like, the working fluid may be transmitted from the inner peripheral surface of the heat exchange portion to the inner peripheral surface of the storage chamber, and the working fluid may not be smoothly recovered with the wick in the storage chamber.

[0005] The present invention has been made in consideration of such circumstances, and an object thereof is to provide a heat transport element capable of smoothly recovering the working fluid condensed in the heat exchange portion with the wick in the storage chamber.

Means for Solving the Problem

[0006] In order to solve the above problems, the heat transport element according to Aspect 1 of the present invention includes a heat exchange part extending in a first direction, and a vapor chamber connected to one end of the heat exchange part and having a contact surface that contacts a heating element. The vapor chamber communicates with the internal space of the heat exchange part and includes a first container that forms a storage chamber in which a working fluid is stored, and a first wick disposed in the storage chamber and capable of holding the working fluid. The heat exchange part has a second container that forms the internal space, and the second container includes a container protrusion that protrudes toward the first wick in the storage chamber at a part of the circumferential direction around the central axis of the second container.

[0007] Aspect 2 of the present invention is the heat transport element according to Aspect 1, wherein the tip of the container protrusion is in contact with the first wick.

[0008] Aspect 3 of the present invention is the heat transport element according to Aspect 1 or 2, wherein the second container has a plurality of container protrusions including the container protrusion, and the plurality of container protrusions are provided at intervals in the circumferential direction of the second container.

[0009] Aspect 4 of the present invention includes a heat exchange part extending in a first direction, and a vapor chamber connected to one end of the heat exchange part and having a contact surface that contacts a heating element. The vapor chamber communicates with the internal space of the heat exchange part and includes a first container that forms a storage chamber in which a working fluid is stored, and a first wick disposed in the storage chamber and capable of holding the working fluid by capillary force. The heat exchange part has a second container that forms the internal space, and a second wick provided in the internal space and capable of holding the working fluid. The second wick includes a wick protrusion that protrudes toward the first wick in the storage chamber at a part of the circumferential direction around the central axis of the second container.

[0010] Aspect 5 of the present invention is the heat transport element according to Aspect 4, wherein the tip of the wick protrusion is in contact with the first wick.

[0011] Aspect 6 of the present invention is the heat transport element according to Aspect 4 or 5, wherein the second wick is provided so as to extend in the first direction on a part of the circumferential direction on the inner circumferential surface of the second container.

[0012] Aspect 7 of the present invention is the heat transport element according to Aspect 6, wherein the heat exchange part has a plurality of second wicks including the second wick, and the plurality of second wicks are provided on the inner circumferential surface of the second container at intervals in the circumferential direction.

[0013] Aspect 8 of the present invention is the heat transport element according to Aspect 4 or 5, wherein the second wick is provided so as to extend in the first direction over the entire circumferential direction on the inner circumferential surface of the second container.

[0014] Aspect 9 of the present invention is the heat transport element according to any one of Aspects 4 to 8, wherein the second wick has a plurality of wick protrusions including the wick protrusion, and the plurality of wick protrusions are provided at intervals in the circumferential direction on the inner circumferential surface of the second container.

[0015] Aspect 10 of the present invention is the heat transport element according to any one of Aspects 1 to 9, further comprising heat dissipation fins joined to the outer peripheral surface of the heat exchange part.

Advantages of the Invention

[0016] According to the above aspect of the present invention, the working fluid condensed in the heat exchange part can be smoothly recovered by the wick in the storage chamber.

Brief Description of the Drawings

[0017]

Figure 1

Figure 2

Figure 3

Figure 4

Figure 5

Figure 6

Figure 7

Figure 8

Figure 9

Modes for Carrying Out the Invention

[0018] Hereinafter, the heat transport element according to the present embodiment will be described with reference to the drawings. (First Embodiment) As shown in FIG. 1, the heat transport element 1A includes a vapor chamber 2, a plurality of heat exchange parts 3A, and a plurality of heat dissipation fins 4. The number of the heat exchange parts 3A may be one. Also, the heat transport element 1A may not include the heat dissipation fins 4. The heat exchange part 3A of the present embodiment is a heat pipe. However, components other than the heat pipe (for example, a flat vapor chamber, etc.) may be used as the heat exchange part 3A.

[0019] (Definition of Directions) In this specification, the direction in which the heat exchange part 3A extends is referred to as the first direction D1. One direction orthogonal to the first direction D1 is referred to as the second direction D2. The direction orthogonal to both the first direction D1 and the second direction D2 is referred to as the third direction D3. Also, in each heat exchange part 3A, the direction around the central axis of the heat exchange part 3A is referred to as the circumferential direction.

[0020] The vapor chamber 2 includes a first container 21 and a first wick 22. The first container 21 is formed of, for example, copper, a copper alloy, aluminum, an aluminum alloy, or the like. The first container 21 may be formed of a material other than those described above.

[0021] The first container 21 has a hollow box shape. The first container 21 is formed in a flat shape in which the outer dimensions in the second direction D2 and the third direction D3 are larger than the thickness dimension in the first direction D1. The first container 21 integrally has a bottom wall portion 23, an outer peripheral wall portion 24, and an upper wall portion 25. The bottom wall portion 23 is disposed on one side (downward in FIG. 1) in the first direction D1 with respect to the upper wall portion 25. The bottom wall portion 23 has, for example, a rectangular shape when viewed from the first direction D1. The bottom wall portion 23 extends along a plane including the second direction D2 and the third direction D3. The bottom wall portion 23 has a contact surface 23f facing one side in the first direction D1. A heating element 100 such as various semiconductor elements including a CPU and a GPU is in contact with the contact surface 23f via a thermal conductive grease 101 containing a material having high thermal conductivity.

[0022] The outer peripheral wall portion 24 rises from the outer peripheral portion of the bottom wall portion 23 to the other side in the first direction D1. The upper wall portion 25 is disposed spaced apart from the bottom wall portion 23 on the other side in the first direction D1. The upper wall portion 25 has, for example, a rectangular shape when viewed from the first direction D1. The upper wall portion 25 extends along a plane including the second direction D2 and the third direction D3. The upper wall portion 25 is provided so as to cover the space inside the outer peripheral wall portion 24 from the other side in the first direction D1.

[0023] A plurality of reinforcing columns 26 are provided between the bottom wall portion 23 and the upper wall portion 25. The plurality of reinforcing columns 26 are arranged at intervals in the second direction D2 and the third direction D3. Each reinforcing column 26 extends in the first direction D1 and connects the bottom wall portion 23 and the upper wall portion 25.

[0024] Inside such a first container 21, a storage chamber 27 surrounded by a bottom wall portion 23, an outer peripheral wall portion 24, and an upper wall portion 25 is formed. The storage chamber 27 extends along a second direction D2 and a third direction D3. An operating fluid is stored in the storage chamber 27.

[0025] The operating fluid is a heat transfer medium made of a well-known phase change material, which undergoes a phase change between a liquid phase and a gas phase in the heat transfer element 1A. For example, as the operating fluid, water (pure water), alcohol, ammonia, etc. can be adopted. Note that, regarding the operating fluid, the case of the liquid phase may be described as "liquid", and the case of the gas phase may be described as "vapor". Also, when the liquid phase and the gas phase are not particularly distinguished, it may be described as the operating fluid. Also, the operating fluid is not shown.

[0026] The first wick 22 is provided in the storage chamber 27. The first wick 22 is arranged along the bottom wall portion 23 in the storage chamber 27. The first wick 22 has a predetermined thickness in the first direction D1. The first wick 22 is arranged spaced apart from the upper wall portion 25 on one side in the first direction D1. The first wick 22 is formed of a powder wick made of a porous body obtained by sintering a metal powder such as copper, a wire wick which is a braided body made of a plurality of metal wires such as copper, etc. The first wick 22 can capture and hold the operating fluid by its capillary force inside the first container 21. A concave portion 22d that is recessed on one side in the first direction D1 is formed in the central portion of the first wick 22. A part of the operating fluid held by the first wick 22 may be exposed in the concave portion 22d.

[0027] A plurality of heat exchange portions 3A are arranged at intervals in the second direction D2 and the third direction D3. The base end portion on one side in the first direction D1 of each heat exchange portion 3A is joined to the vapor chamber 2. The heat exchange portion 3A protrudes and extends from the upper wall portion 25 of the vapor chamber 2 to the other side in the first direction D1.

[0028] The heat exchange unit 3A includes a cylindrical second container 31 and a second wick 32. The second container 31 is formed of, for example, copper, a copper alloy, aluminum, an aluminum alloy, or the like. The second container 31 may be formed of a material other than those described above.

[0029] The second container 31 is a hollow cylinder extending in the first direction D1, with one end portion 31s on one side in the first direction D1 being an open end and the other end portion 31t on the other side in the first direction D1 being a closed end. A plurality of second containers 31 are provided at intervals in the second direction D2 and the third direction D3. In the present embodiment, two second containers 31 are provided at intervals in the second direction D2. Two second containers 31 are provided at intervals in the third direction D3. Note that the number of second containers 31 may be one, two, three, or five or more.

[0030] An internal space 37 extending in the first direction D1 is formed inside the second container 31. One end portion 31s of the second container 31 is inserted into a through hole 25h formed in the upper wall portion 25 of the vapor chamber 2 and joined to the upper wall portion 25 by brazing, welding, adhesion, or the like. Thereby, the internal space 37 inside the second container 31 communicates with the storage chamber 27 inside the vapor chamber 2.

[0031] FIG. 2 is a cross-sectional view of the heat exchange unit 3A. As shown in FIGS. 1 and 2, the second wick 32 is provided inside the second container 31. The second wick 32 is disposed inside the second container 31 along the inner peripheral surface 31f of the second container 31. As shown in FIG. 2, the second wick 32 is provided over the entire circumference in the circumferential direction around the central axis C of the second container 31 on the inner peripheral surface 31f of the second container 31. The second wick 32 extends in the first direction D1 along the inner peripheral surface 31f of the second container 31.

[0032] The second wick 32 is formed from a powder wick made of a porous body obtained by sintering a metal powder such as copper, a wire wick which is a braided body made of a plurality of metal wires such as copper, or the like. The second wick 32 can capture and hold the working fluid condensed in the second container 31 by its capillary force within the second container 31. Note that in the present embodiment, the second wick 32 is not an essential component, and the second wick 32 may be omitted.

[0033] As shown in FIG. 1, the heat radiation fins 4 are joined to the outer peripheral surface of the heat exchange portion 3A. The heat radiation fins 4 are formed in a plate shape extending along the second direction D2 and the third direction D3. A plurality of heat radiation fins 4 are provided at intervals in the first direction D1. A cylindrical sleeve 41 extending in the first direction D1 is provided on the outer peripheral surface of the heat exchange portion 3A. Each heat radiation fin 4 is joined to the second container 31 of the heat exchange portion 3A via the sleeve 41. The heat radiation fins 4 and the sleeve 41 are formed of, for example, copper, a copper alloy, aluminum, an aluminum alloy, or the like. The heat radiation fins 4 and the sleeve 41 may be formed of materials other than those described above.

[0034] FIG. 3 is a view of the heat exchange portion 3A as seen from the second direction D2. As shown in FIGS. 1 and 3, in the heat transport element 1A as described above, each heat exchange portion 3A includes a container protrusion 38. The container protrusion 38 is formed in a part of the circumferential direction around the central axis of the second container 31. The container protrusion 38 may be provided, for example, in a range of 1 / 6 to 1 / 3 of the circumferential direction of the second container 31. In the embodiment of the present disclosure, the container protrusion 38 is formed over a range of about 1 / 4 of the circumferential direction of the second container 31.

[0035] As shown in FIG. 1, the container protrusion 38 protrudes from the lower surface 25b of the upper wall portion 25 to one side in the first direction D1. The tip 38s of the container protrusion 38 is in contact with the first wick 22 within the storage chamber 27 of the first container 21. The tip 38s of the container protrusion 38 may be inserted (embedded) within the first wick 22. Further, the tip 38s of the container protrusion 38 may penetrate through the first wick 22 and contact the bottom wall portion 23. Also, the tip 38s of the container protrusion 38 may be spaced apart from the first wick 22 as long as it can promptly capture the working fluid that has swelled toward the first wick side due to surface tension from the tip 38s.

[0036] Next, the operation of the heat transport element 1A will be described. The heat transport element 1A is used in a state where the contact surface 23f is in contact with the heating element 100. The posture of the heat transport element 1A is preferably such that, for example, the first direction D1 coincides with the vertical direction. However, the heat transport element 1A may be used in a posture where the first direction D1 is inclined with respect to the vertical direction. The heat transport element 1A may be arranged in a posture where the first direction D1 coincides with the horizontal direction.

[0037] In the heat transport element 1A, the heat generated by the heating element 100 is transmitted through the vapor chamber 2 to the liquid working fluid within the storage chamber 27. As a result, when the working fluid is heated to a temperature equal to or higher than the saturation temperature and vaporizes, the vapor flows from within the storage chamber 27 into the internal space 37 within the heat exchange portion 3A. The heat of the working fluid that has flowed into the internal space 37 is transmitted to the heat dissipation fins 4 through the heat exchange portion 3A. The heat of the working fluid transmitted to the heat dissipation fins 4 is dissipated into the atmosphere surrounding the heat dissipation fins 4. Thereby, the temperature of the working fluid within the internal space 37 decreases, and when the working fluid condenses, the liquid working fluid is captured by the second wick 32 provided within the second container 31 of the heat exchange portion 3A, and returns through the second wick 32 to the first wick 22 within the storage chamber 27 of the vapor chamber 2. At this time, at one end portion 31s of the heat exchange portion 3A, the working fluid moving through the second wick 32 travels along the surface of the container protrusion 38 and smoothly moves to the first wick 22 within the storage chamber 27.

[0038] The liquid that has returned to the first wick 22 is heated again by the heating element 100 and evaporates. In this way, the heat transport element 1A can repeatedly transport the heat of the heating element 100 to the heat dissipation fins 4. Therefore, the heating element 100 can be cooled.

[0039] As described above, the heat transport element 1A of the present embodiment includes a heat exchange portion 3A extending in the first direction D1, and a vapor chamber 2 connected to one end portion 31s of the heat exchange portion 3A and having a contact surface 23f that contacts the heating element 100. The vapor chamber 2 communicates with the internal space 37 of the heat exchange portion 3A and includes a first container 21 that forms a storage chamber 27 in which the working fluid is stored, and a first wick 22 disposed in the storage chamber 27 and capable of holding the working fluid. The heat exchange portion 3A has a second container 31 that forms the internal space 37, and the second container 31 is provided with a container protrusion 38 that protrudes toward the first wick 22 in the storage chamber 27 at a part of the circumferential direction around the central axis C of the second container 31.

[0040] According to such a configuration, the working fluid condensed in the heat exchange portion 3A moves from the heat exchange portion 3A along the container protrusion 38 to the first wick 22 in the storage chamber 27. If there is no container protrusion 38, the liquid may remain near one end portion 31s of the second container 31 or on the lower surface 25b of the upper wall portion 25, making it difficult for the liquid to return to the first wick 22. Due to the presence of the container protrusion 38, the working fluid condensed in the heat exchange portion 3A can be smoothly recovered to the first wick 22 in the storage chamber 27.

[0041] Further, the tip portion 38s of the container protrusion 38 is in contact with the first wick 22. With this configuration, the working fluid condensed in the heat exchange portion 3A moves more quickly from the container protrusion 38 to the first wick 22. Therefore, the working fluid condensed in the heat exchange portion 3A can be recovered even more smoothly to the first wick 22 in the storage chamber 27.

[0042] Further, the heat transport element 1A further includes a heat dissipation fin 4 joined to the outer peripheral surface of the heat exchange section 3A. With this configuration, the heat of the vaporized working fluid can be efficiently dissipated into the surrounding atmosphere through the heat dissipation fin 4.

[0043] (Modification of the First Embodiment) In addition, in the above-described first embodiment, only one container protrusion 38 is provided in a part of the circumferential direction of the second container 31, but the present invention is not limited to this. For example, as shown in FIG. 4, a plurality of container protrusions 38 may be provided at intervals in the circumferential direction of the second container 31. In this modification, for example, two container protrusions 38 are provided at intervals in the circumferential direction of the second container 31. With this configuration, the working fluid condensed in the heat exchange section 3A moves more quickly from the plurality of container protrusions 38 to the first wick 22.

[0044] (Second Embodiment) Next, a second embodiment of the heat transport element according to the present invention will be described. The basic configuration is the same as that of the first embodiment. Therefore, the same components are denoted by the same reference numerals and the description thereof is omitted, and only the differences will be described.

[0045] FIG. 5 is a cross-sectional view showing a heat transport element 1B according to the second embodiment. As shown in FIG. 5, the heat transport element 1B includes a vapor chamber 2, a heat exchange section 3B, and a heat dissipation fin 4.

[0046] FIG. 6 is a cross-sectional view of the heat exchange section of the heat transport element according to the second embodiment as viewed from the first direction. As shown in FIGS. 5 and 6, in the present embodiment, the heat exchange section 3B includes a cylindrical second container 31 and a second wick 33. The second wick 33 is disposed in the second container 31 along the inner peripheral surface 31f of the second container 31. The second wick 33 is provided, for example, two at intervals in the circumferential direction of the second container 31 on the inner peripheral surface 31f of the second container 31. The second wick 33 extends in the first direction D1 along the inner peripheral surface 31f of the second container 31.

[0047] The second wick 33 is formed from a powder wick made of a porous body obtained by sintering a metal powder such as copper, a wire wick which is a braided body made of a plurality of metal wires such as copper, or the like. The second wick 33 can capture and hold the working fluid condensed in the second container 31 by its capillary force within the second container 31.

[0048] FIG. 7 is a view of the heat exchange part of FIG. 6 as seen from the second direction. As shown in FIGS. 5 and 7, in the heat transport element 1B as described above, each heat exchange part 3B includes a wick protrusion 39. The wick protrusion 39 is formed in a part of the circumferential direction around the central axis C of the heat exchange part 3B. The wick protrusion 39 is continuously provided on each of two second wicks 33 spaced apart in the circumferential direction within the second container 31. Each wick protrusion 39 is provided in a range of, for example, 1 / 6 to 1 / 3 of the circumferential direction of the heat exchange part 3B. In an embodiment of the present disclosure, the wick protrusion 39 is formed in a range of, for example, about 1 / 4 of the circumferential direction of the heat exchange part 3B.

[0049] The wick protrusion 39 protrudes to one side in the first direction D1 from one end portion 31s of the second container 31. The tip portion 39s of the wick protrusion 39 is in contact with the first wick 22 within the storage chamber 27 of the first container 21. The tip portion 39s of the wick protrusion 39 may be inserted (embedded) within the first wick 22. Further, the tip portion 39s of the wick protrusion 39 may penetrate the first wick 22 and be in contact with the bottom wall portion 23. Further, the tip portion 39s of the wick protrusion 39 may be separated from the first wick 22 as long as it can quickly capture the working fluid swollen toward the first wick side by surface tension from the tip portion 39s.

[0050] In such a heat transport element 1B, the working fluid condensed in the heat exchange section 3B is captured by the second wick 33 provided in the second container 31, passes through the second wick 33, and returns to the storage chamber 27 in the vapor chamber 2. At this time, at one end 31s of the heat exchange section 3B, the working fluid moving through the second wick 33 travels along the surface of the wick protrusion 39 and smoothly moves to the first wick 22 in the storage chamber 27.

[0051] As described above, the heat transport element 1B of the present embodiment includes a heat exchange section 3B extending in the first direction D1, and a vapor chamber 2 connected to one end 31s of the heat exchange section 3B and having a contact surface 23f that contacts the heating element 100. The vapor chamber 2 communicates with the internal space 37 of the heat exchange section 3B and includes a first container 21 that forms a storage chamber 27 in which the working fluid is stored, and a first wick 22 disposed in the storage chamber 27 and capable of holding the working fluid by capillary force. The heat exchange section 3B includes a second container 31 that forms the internal space 37, and a second wick 33 provided in the internal space 37 and capable of holding the working fluid. The second wick 33 includes a wick protrusion 39 that protrudes toward the first wick 22 in the storage chamber 27 at a part in the circumferential direction around the central axis C of the second container 31.

[0052] According to such a configuration, the working fluid condensed in the heat exchange section 3B moves from the heat exchange section 3B along the wick protrusion 39 to the first wick 22 in the storage chamber 27. Therefore, the working fluid condensed in the heat exchange section 3B can be smoothly recovered to the first wick 22 in the storage chamber 27.

[0053] Further, the tip 39s of the wick protrusion 39 is in contact with the first wick 22. With this configuration, the working fluid condensed in the heat exchange section 3B moves more quickly from the wick protrusion 39 to the first wick 22. Therefore, the working fluid condensed in the heat exchange section 3B can be recovered more smoothly to the first wick 22 in the storage chamber 27.

[0054] Further, the plurality of second wicks 33 are provided on the inner peripheral surface of the second container 31 at intervals in the circumferential direction, and each extends in the first direction D1. With this configuration, the working fluid condensed in the heat exchange section 3B can be smoothly moved to the wick protrusion 39 along the second wick 33 extending in the first direction D1 within the heat exchange section 3B.

[0055] Further, the plurality of wick protrusions 39 are provided on the inner peripheral surface of the second container 31 at intervals in the circumferential direction. Thereby, the working fluid condensed in the heat exchange section 3B can be more smoothly moved to the first wick 22 in the storage chamber 27 along the plurality of wick protrusions 39.

[0056] (Modification of the Second Embodiment) In the above second embodiment, two second wicks 33 are provided at intervals in the circumferential direction of the second container 31, but the present invention is not limited to this. For example, as shown in FIG. 3, the second wick 33 may be provided over the entire circumference in the circumferential direction of the second container 31. In this case, two wick protrusions 39 spaced apart in the circumferential direction may be provided so as to protrude from the second wick 33 to one side in the first direction D1. Also in this configuration, the working fluid condensed in the heat exchange section 3B moves more quickly from the plurality (two) of wick protrusions 39 to the first wick 22.

[0057] Further, as shown in FIG. 8, the second wick 33 may be provided at only one location in the circumferential direction of the second container 31. In this case, the wick protrusion 39 is also provided at only one location in the circumferential direction of the second container 31. Also in this configuration, the working fluid condensed in the heat exchange section 3B moves more quickly from the wick protrusion 39 to the first wick 22.

[0058] Note that the technical scope of the present invention is not limited to the embodiments, and various modifications can be made without departing from the spirit of the present invention.

[0059] For example, in the first embodiment, the second container 31 is provided with a container protrusion 38, and in the second embodiment, the second wick 33 is provided with a wick protrusion 39. However, it is also possible to provide both the container protrusion 38 provided on the second container 31 and the wick protrusion 39 provided on the second wick 33.

[0060] In addition, within the scope not departing from the gist of the present invention, it is possible as appropriate to replace the components in the above-described embodiments with well-known components, and the above-described embodiments and modified examples may also be combined as appropriate.

[0061] (Study Example) Regarding the heat transport elements 1A and 1B shown in the first and second embodiments and their respective modified examples, studies were conducted, and the results are shown below. As study targets, heat transport elements equipped with the following Heat Pipe of Example 1 - 4 and Comparative Example were prepared. Example 1: A heat pipe having a container protrusion provided on the second container (corresponding to the configuration of FIGS. 1 - 3) Example 2: A heat pipe having a second wick and a wick protrusion provided at one location in the circumferential direction of the second container (corresponding to the configuration of FIG. 8) Example 3: A heat pipe having a second wick provided over the entire circumference in the circumferential direction of the second container and having wick protrusions at two locations in the circumferential direction (corresponding to the configuration of FIGS. 5 - 7) Comparative Example: A heat pipe not having a container protrusion and a wick protrusion

[0062] For each of Examples 1 to 4 and Comparative Examples as described above, the calorific value of the heater corresponding to the heating element was changed, and the total thermal resistance in the vapor chamber (VC) was measured. The results are shown in FIG. 9. As shown in FIG. 9, it was confirmed that the total thermal resistance was low in any of Examples 1 to 4 compared with the Comparative Example. Also, among Examples 1 to 4, it was confirmed that the total thermal resistance was particularly low in Examples 1 and 4. From this, it can be estimated that the working fluid condensed in the heat pipe was smoothly recovered by the wick (first wick) in the storage chamber of the vapor chamber, thereby suppressing the total thermal resistance in the vapor chamber.

Explanation of Reference Numerals

[0063] 1A, 1B... Heat transport elements 2... Vapor chamber 3A, 3B... Heat exchange parts (heat pipes) 4... Radiation fins 21... First container 22... First wick 23f... Contact surface 27... Storage chamber 31... Second container 31f... Inner peripheral surface 31s... One end part 32, 33... Second wicks 37... Internal space 38... Container protrusion 38s... Tip part 39... Wick protrusion 39s... Tip part 100... Heating element

Claims

1. A heat exchange part extending in a first direction, and a vapor chamber connected to one end of the heat exchange part and having a contact surface that contacts a heating element. The vapor chamber includes a first container that communicates with an internal space of the heat exchange part and forms a storage chamber in which a working fluid is stored, and a first wick disposed in the storage chamber and capable of holding the working fluid. The heat exchange part has a second container that forms the internal space, and the second container includes a container protrusion that protrudes toward the first wick in the storage chamber at a part in a circumferential direction around a central axis of the second container. The heat transport element.

2. The heat transport element according to claim 1, wherein a tip of the container protrusion contacts the first wick.

3. The second container has a plurality of container protrusions including the container protrusion, and the plurality of container protrusions are provided at intervals in the circumferential direction. The heat transport element according to claim 1 or 2.

4. A heat exchange part extending in a first direction, and a vapor chamber connected to one end of the heat exchange part and having a contact surface that contacts a heating element. The vapor chamber includes a first container that communicates with an internal space of the heat exchange part and forms a storage chamber in which a working fluid is stored, and a first wick disposed in the storage chamber and capable of holding the working fluid by capillary force. The heat exchange part includes a second container that forms the internal space, and a second wick provided in the internal space and capable of holding the working fluid. The second wick is a heat transfer element provided with a wick protrusion that protrudes toward the first wick in the storage chamber, at a part in the circumferential direction around the central axis of the second container.

5. The heat transfer element according to claim 4, wherein a tip of the wick protrusion is in contact with the first wick.

6. The heat transfer element according to claim 4 or 5, wherein the second wick is provided so as to extend in the first direction, at a part in the circumferential direction on the inner circumferential surface of the second container.

7. The heat exchange part has a plurality of second wicks including the second wick, The heat transfer element according to claim 6, wherein the plurality of second wicks are provided on the inner circumferential surface of the second container, at intervals in the circumferential direction.

8. The heat transfer element according to claim 4 or 5, wherein the second wick is provided so as to extend in the first direction, over the entire circumference in the circumferential direction on the inner circumferential surface of the second container.

9. The second wick has a plurality of wick protrusions including the wick protrusion, The heat transfer element according to claim 4 or 5, wherein the plurality of wick protrusions are provided on the inner circumferential surface of the second container, at intervals in the circumferential direction.

10. The heat transfer element according to claim 1 or 4, further comprising heat dissipation fins joined to an outer circumferential surface of the heat exchange part.

Images