Heat dissipation device and electronic device

Abstract

To provide a thermal diffusion device in which the expansion / contraction of a bellows structure is not obstructed due to a strut supporting a housing from an inner space side.SOLUTION: A vapor chamber (thermal diffusion device) 1A is equipped with a housing 10 that has a first inner surface 10a and a second inner surface 10b opposite to each other in a thickness direction T, and is provided with an inner space, a working medium 20 sealed in the inner space of the housing 10, a wick 30 that is provided at a position apart from the first inner surface 10a in the inner space of the housing 10, and a strut 40a that is provided on the second inner surface 10b and penetrates the wick 30 in a thickness direction T to reach the first inner surface 10a. The first inner surface 10a includes a bellow surface 15a having a bellows structure. The strut 40a contacts with the bellows surface 15a and is not fixed to the bellows surface 15a.SELECTED DRAWING: Figure 2

Description

Technical Field

[0001] The present invention relates to a heat diffusion device and an electronic device.

Background Art

[0002] In recent years, due to the high integration and high performance of elements, the amount of heat generated has been increasing. Also, due to the miniaturization of products, the heat generation density has been increasing. Such a situation is particularly prominent in the field of mobile terminals such as smartphones and tablets. Under such circumstances, it has become important to take heat dissipation measures.

[0003] As a member for heat dissipation measures, a graphite sheet or the like is often used, but since its heat transport amount is not sufficient, the use of various heat diffusion devices (for example, a vapor chamber) capable of effectively diffusing heat is being considered.

[0004] Patent Document 1 discloses a configuration of a vapor chamber including a bottom layer, an upper layer, a wick layer (mesh layer), and a vapor layer having a plurality of struts.

Prior Art Documents

Patent Documents

[0005]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0006] In the configuration of the vapor chamber described in FIG. 7A of Patent Document 1, the struts for securing the vapor layer are provided so as to be in contact with both the wavy structure of the upper layer and the wick layer (mesh layer). However, in the configuration of the vapor chamber described in FIG. 7A of Patent Document 1, when the wavy structure of the upper layer attempts to expand and contract, the movement of the expansion and contraction of the wavy structure is inhibited by the struts.

[0007] Furthermore, in the configuration of the vapor chamber described in FIG. 7A of Patent Document 1, although the support columns are provided in the corrugated structure of the upper layer, it is difficult to provide the support columns in the corrugated structure without inhibiting the expansion and contraction movement of the corrugated structure. In particular, when attempting to thin the vapor chamber, in order to ensure the stretchability of the corrugated structure of the upper layer while suppressing the thickness of the corrugated structure of the upper layer, it is required to make the corrugated structure into a fine corrugated structure with a small height and pitch, or to reduce the thickness of the upper layer itself. However, it is even more difficult to provide support columns in such a fine corrugated structure of the upper layer with a small thickness without inhibiting the expansion and contraction movement of the corrugated structure.

[0008] Also, in the configuration of the vapor chamber described in FIG. 7A of Patent Document 1, the support columns are provided in the wick layer. Here, the wick layer functions as a member for refluxing the liquid-phase working medium to the evaporation section, and its performance greatly affects the heat transport capacity of the vapor chamber. Therefore, as the wick layer, it is required to select a member with appropriate specifications such as pore diameter and porosity. However, it is difficult to select a member that can provide support columns while having appropriate specifications as described above for the wick layer.

[0009] For these reasons, in the configuration of the vapor chamber described in FIG. 7A of Patent Document 1, it is difficult to provide support columns in the corrugated structure of the upper layer and the wick layer.

[0010] As described above, in a conventional vapor chamber having a configuration such as that described in FIG. 7A of Patent Document 1, there is room for improvement in that the expansion and contraction movement of the bellows structure is not inhibited by the support columns that support the housing from the inner space side.

[0011] Note that the above circumstances are common not only to vapor chambers but also to heat dissipation devices capable of dissipating heat by a configuration similar to that of vapor chambers.

[0012] The present invention has been made to solve the above problems, and an object thereof is to provide a heat diffusion device in which the expansion and contraction movement of a bellows structure is not inhibited by a support column that supports a housing from the inner space side. Another object of the present invention is to provide an electronic device having the above heat diffusion device.

Means for Solving the Problems

[0013] The heat diffusion device of the present invention includes a housing having a first inner surface and a second inner surface facing each other in the thickness direction and provided with an inner space, a working medium enclosed in the inner space of the housing, a wick provided at a position away from the first inner surface in the inner space of the housing, and a support column provided on the second inner surface and penetrating the wick in the thickness direction to reach the first inner surface. The first inner surface includes a bellows surface having a bellows structure, and the support column is in contact with the bellows surface and is not fixed to the bellows surface.

[0014] The electronic device of the present invention is characterized by including the heat diffusion device of the present invention.

Effects of the Invention

[0015] According to the present invention, it is possible to provide a heat diffusion device in which the expansion and contraction movement of a bellows structure is not inhibited by a support column that supports a housing from the inner space side. Further, according to the present invention, it is possible to provide an electronic device having the above heat diffusion device.

Brief Description of the Drawings

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Figure 16

[0017] Hereinafter, the heat diffusion device of the present invention and the electronic device of the present invention will be described. Note that the present invention is not limited to the following configurations, and may be appropriately changed without departing from the gist of the present invention. Also, combinations of a plurality of the individual preferred configurations described below are also within the scope of the present invention.

[0018] Each of the embodiments shown below is illustrative, and it goes without saying that partial substitution or combination of the configurations shown in different embodiments is possible. In the embodiments after the second embodiment, descriptions of matters common to the first embodiment will be omitted, and different points will be mainly described. In particular, the same operational effects due to the same configurations will not be sequentially mentioned for each embodiment.

[0019] In the following description, when the embodiments are not particularly distinguished, they are simply referred to as "the heat diffusion device of the present invention" and "the electronic device of the present invention".

[0020] In each of the following embodiments, as an example of the heat diffusion device of the present invention, a vapor chamber is shown. The heat diffusion device of the present invention is also applicable to heat diffusion devices such as heat pipes.

[0021] The drawings shown below are schematic diagrams, and their dimensions, scales of aspect ratios, etc. may be different from those of actual products.

[0022] In this specification, terms indicating the relationship between elements (for example, "parallel", "perpendicular", etc.) and terms indicating the shape of elements do not only mean the exact strict aspect, but also mean a substantially equivalent range, for example, a range including a difference of about several percent.

[0023] [Heat Diffusion Device] The heat diffusion device of the present invention includes a housing having a first inner surface and a second inner surface facing each other in the thickness direction and provided with an internal space, a working medium enclosed in the internal space of the housing, a wick provided in the internal space of the housing at a position away from the first inner surface, and a support provided on the second inner surface and penetrating the wick in the thickness direction to reach the first inner surface. The first inner surface includes a bellows surface having a bellows structure, and the support is in contact with the bellows surface and not fixed to the bellows surface.

[0024] The heat diffusion device of the present invention can be freely deformed by utilizing the expansion and contraction of the bellows structure. The features of each of the following embodiments may be satisfied in any state before, during, or after the expansion and contraction of the bellows structure.

[0025] <Embodiment 1> FIG. 1 is a perspective schematic view showing an example of the heat diffusion device according to Embodiment 1 of the present invention.

[0026] The vapor chamber (heat diffusion device) 1A shown in FIG. 1 has a housing 10.

[0027] The housing 10 is hermetically sealed and has a hollow structure.

[0028] A heat source HS, which is a heating element, is provided on the outer surface of the housing 10.

[0029] Examples of the heat source HS include electronic components and the like.

[0030] In this specification, the length direction, the thickness direction, and the width direction are defined as the directions L, T, and W, respectively, as shown in FIG. 1 and the like. The length direction L, the thickness direction T, and the width direction W are perpendicular to each other. Also, the direction perpendicular to the thickness direction T and including the length direction L and the width direction W is defined as the surface direction.

[0031] The vapor chamber 1A is preferably planar as a whole. That is, the housing 10 is preferably planar as a whole.

[0032] In this specification, "planar" includes shapes such as plate-like and sheet-like, and refers to a shape in which the dimensions in the length direction and the width direction are considerably larger than the dimension in the thickness direction. For example, it means a shape in which the dimensions in the length direction and the width direction are 10 times or more, preferably 100 times or more, the dimension in the thickness direction.

[0033] The size of the vapor chamber 1A is not particularly limited.

[0034] The dimension in the length direction L and the dimension in the width direction W of the vapor chamber 1A are each preferably 5 mm or more and 500 mm or less, more preferably 20 mm or more and 300 mm or less, and still more preferably 50 mm or more and 200 mm or less.

[0035] The dimension in the length direction L and the dimension in the width direction W of the vapor chamber 1A may be the same as each other or different from each other.

[0036] The dimension in the thickness direction T of the vapor chamber 1A is preferably 100 μm or more and 1 mm or less.

[0037] The dimension in the length direction L, the dimension in the thickness direction T, and the dimension in the width direction W of the vapor chamber 1A are each defined as the maximum dimension in the length direction L, the thickness direction T, and the width direction W.

[0038] The housing 10 is preferably composed of a first sheet 11 and a second sheet 12 whose outer edges are joined to each other.

[0039] In this specification, the sheet also includes forms such as foil and film.

[0040] When the outer edges of the first sheet 11 and the second sheet 12 are joined to each other, they may overlap so that the ends coincide with each other, or they may overlap with the ends shifted.

[0041] It is preferable that the outer edges of the first sheet 11 and the second sheet 12 are directly joined to each other.

[0042] Examples of the joining method of the outer edges of the first sheet 11 and the second sheet 12 include laser welding, resistance welding, diffusion bonding, brazing, TIG welding (tungsten-inert gas welding), ultrasonic bonding, resin encapsulation, and the like. Among them, laser welding, resistance welding, or brazing is preferable.

[0043] The constituent materials of the first sheet 11 and the second sheet 12 are not particularly limited as long as they have characteristics suitable for a thermal diffusion device (for example, the vapor chamber 1A), such as thermal conductivity, strength, flexibility, and flexibility. The constituent materials of the first sheet 11 and the second sheet 12 are preferably metals, for example, copper, nickel, aluminum, magnesium, titanium, iron, alloys mainly composed of at least one of these metals, and the like. Particularly preferably, copper or its alloy, aluminum or its alloy, or stainless steel (an alloy of iron).

[0044] The constituent materials of the first sheet 11 and the second sheet 12 may be the same as each other or different from each other.

[0045] When the constituent materials of the first sheet 11 and the second sheet 12 are different from each other, different functions can be exhibited by the first sheet 11 and the second sheet 12. Such functions are not particularly limited, but examples include a heat conduction function, an electromagnetic wave shielding function, and the like.

[0046] The dimensions in the thickness direction T of the first sheet 11 and the second sheet 12 are each preferably 10 μm or more and 200 μm or less, more preferably 20 μm or more and 60 μm or less.

[0047] The dimensions in the thickness direction T of the first sheet 11 and the second sheet 12 may be the same as each other or different from each other.

[0048] The dimensions of the first sheet 11 and the second sheet 12 in the thickness direction T are each defined as the maximum dimension in the thickness direction T.

[0049] The dimensions of the first sheet 11 and the second sheet 12 in the thickness direction T may each be the same throughout or may be different in part.

[0050] Examples of the planar shape of the housing 10 when viewed from the thickness direction T include polygons such as triangles and rectangles, circles, ellipses, shapes combining these, etc. Also, the planar shape of the housing 10 may be L-shaped, C-shaped (U-shaped), stepped, etc. Further, the housing 10 may be provided with a through-hole in the thickness direction T. The planar shape of the housing 10 may be a shape corresponding to the use of the heat dissipation device (for example, the vapor chamber 1A), a shape corresponding to the mounting location of the heat dissipation device (for example, the vapor chamber 1A), or a shape corresponding to other components existing in the vicinity.

[0051] The size of the housing 10 is not particularly limited.

[0052] The dimension of the housing 10 in the length direction L and the dimension in the width direction W are each preferably 5 mm or more and 500 mm or less, more preferably 20 mm or more and 300 mm or less, and still more preferably 50 mm or more and 200 mm or less.

[0053] The dimension of the housing 10 in the length direction L and the dimension in the width direction W may be the same as each other or may be different from each other.

[0054] The dimension of the housing 10 in the thickness direction T is preferably 100 μm or more and 1 mm or less.

[0055] The dimension of the housing 10 in the length direction L, the dimension in the thickness direction T, and the dimension in the width direction W are each defined as the maximum dimension in the length direction L, the thickness direction T, and the width direction W.

[0056] In FIG. 1, an embodiment in which the housing 10 is composed of two sheets, i.e., a first sheet 11 and a second sheet 12, is illustrated. However, the housing 10 may be composed of one sheet or three or more sheets.

[0057] FIG. 2 is a schematic cross-sectional view showing an example of the internal structure of the heat diffusion device according to Embodiment 1 of the present invention.

[0058] As shown in FIG. 2, the vapor chamber 1A includes a housing 10, a working medium 20, a wick 30, and a support column 40a.

[0059] As shown in FIG. 2, the housing 10 has a first inner surface 10a and a second inner surface 10b facing each other in the thickness direction T.

[0060] In the example shown in FIG. 2, the housing 10 is composed of a first sheet 11 and a second sheet 12. The inner surface of the first sheet 11 corresponds to the first inner surface 10a, and the inner surface of the second sheet 12 corresponds to the second inner surface 10b.

[0061] As shown in FIG. 2, the first inner surface 10a includes a bellows surface 15a having a bellows structure. The outer surface facing the first inner surface 10a, here, the outer surface facing the inner surface of the first sheet 11, also includes a bellows surface having a bellows structure at a position facing the bellows surface 15a. Thus, the first sheet 11 is provided with a bellows structure.

[0062] In this specification, the bellows structure includes, for example, not only a structure in which convex portions and concave portions having folded corners (sharp corners) are arranged in one direction by folding a sheet into mountain folds and valley folds, but also a wavy structure in which convex portions and concave portions having no folded corners (sharp corners) are arranged in one direction by bending the sheet in a meandering manner.

[0063] The vapor chamber 1A can be deformed by utilizing the expansion and contraction of the bellows structure of the bellows surface 15a.

[0064] As shown in FIG. 2, convex portions 16a and concave portions 17a exist on the bellows surface 15a.

[0065] In the example shown in FIG. 2, there are a plurality of convex portions 16a and concave portions 17a, which are alternately arranged in the length direction L.

[0066] Regarding the convex portion 16a and the concave portion 17a adjacent to each other in the plane direction (in FIG. 2, the length direction L), the distance (height) in the thickness direction T between the tip of the convex portion 16a and the bottom end of the concave portion 17a is preferably 2 mm or less, more preferably 1 mm or less.

[0067] When there are a plurality of convex portions 16a and concave portions 17a as shown in FIG. 2, the plurality of convex portions 16a and concave portions 17a may be present such that the distance in the thickness direction T between the tip of the convex portion 16a and the bottom end of the concave portion 17a is constant throughout for the convex portion 16a and the concave portion 17a adjacent to each other in the plane direction, or may be present such that the distance in the thickness direction T between the tip of the convex portion 16a and the bottom end of the concave portion 17a is not constant at least in part.

[0068] The center-to-center distance (pitch) between the tips of the convex portions 16a adjacent to each other in the plane direction (in FIG. 2, the length direction L) is preferably 2 mm or less, more preferably 1 mm or less.

[0069] When there are a plurality of convex portions 16a as shown in FIG. 2, the plurality of convex portions 16a may be present such that the center-to-center distance between the tips of the convex portions 16a adjacent to each other in the plane direction is constant throughout, or may be present such that the center-to-center distance between the tips of the convex portions 16a adjacent to each other in the plane direction is not constant at least in part.

[0070] The center-to-center distance (pitch) between the bottom ends of the concave portions 17a adjacent to each other in the plane direction (in FIG. 2, the length direction L) is preferably 2 mm or less, more preferably 1 mm or less.

[0071] When there are a plurality of recesses 17a as shown in Fig. 2, the plurality of recesses 17a may be arranged such that the center-to-center distance between the bottom ends of the recesses 17a adjacent in the plane direction is constant throughout, or may be arranged such that the center-to-center distance between the bottom ends of the recesses 17a adjacent in the plane direction is not constant at least in part.

[0072] The bellows surface 15a only needs to be present on at least a part of the first inner surface 10a. That is, the bellows surface 15a may be present on the entire first inner surface 10a, or may be present on a part of the first inner surface 10a. When the bellows surface 15a is present on a part of the first inner surface 10a, it is preferably present in a region excluding the outer edge portion of the first inner surface 10a.

[0073] The second sheet 12 may be, for example, a flat plate having a constant dimension in the thickness direction T, or may have a shape in which the dimension in the thickness direction T of the outer edge portion is larger than that of the portion other than the outer edge portion. Alternatively, the second sheet 12 may have a constant dimension in the thickness direction T and a shape in which the portion other than the outer edge portion is convex outward with respect to the outer edge portion. In this case, a recess is provided in the outer edge portion of the housing 10. Such a recess in the outer edge portion of the housing 10 can be used when mounting a heat dissipation device (for example, the vapor chamber 1A). In addition, other components can be arranged in the recess in the outer edge portion of the housing 10.

[0074] The housing 10 is provided with an internal space. More specifically, the housing 10 is provided with an internal space surrounded by the first inner surface 10a and the second inner surface 10b.

[0075] The housing 10 preferably has an evaporation portion in the internal space.

[0076] The evaporation portion is a portion that evaporates the liquid-phase working medium 20 described later and changes it into the gas-phase working medium 20. More specifically, the evaporation portion corresponds to a portion in the internal space of the housing 10 near the heat source HS shown in Fig. 1 and is heated by the heat source HS.

[0077] The number of evaporation units may be only one or plural according to the number of heat sources HS. That is, on the outer surface of the housing 10, only one heat source HS may be provided, or plural heat sources HS may be provided.

[0078] If the surface on which the heat source is provided has a bellows structure, the contact area between the heat source and the heat diffusion device (for example, a vapor chamber) becomes small, so the thermal resistance increases. Further, in the heat diffusion device (for example, a vapor chamber), since one of the features is that there is no restriction on the contact position with the heat source, the configuration in which the surface on which the heat source is provided has a bellows structure is not preferable.

[0079] From the above, for the first sheet 11 provided with the bellows structure, it is preferable that the heat source HS is not provided on the outer surface opposite to the inner surface of the first sheet 11, that is, the outer surface opposite to the first inner surface 10a.

[0080] On the other hand, the heat source HS is preferably provided on the outer surface opposite to the inner surface of the second sheet 12, that is, the outer surface opposite to the second inner surface 10b. In this case, it is preferable that the second sheet 12 is not provided with a bellows structure. That is, it is preferable that the second inner surface 10b does not include a bellows surface having a bellows structure.

[0081] As shown in FIG. 2, the working medium 20 is enclosed in the internal space of the housing 10.

[0082] The working medium 20 is not particularly limited as long as it can cause a gas-liquid phase change in the environment inside the housing 10. Examples of the working medium 20 include water, alcohols, alternative refrigerants, etc. The working medium 20 is preferably an aqueous compound, and among them, water is particularly preferable.

[0083] As shown in FIG. 2, the wick 30 is provided at a position away from the first inner surface 10a in the internal space of the housing 10.

[0084] The space between the wick 30 and the first inner surface 10a functions as a vapor flow path mainly containing the gaseous working medium 20. Here, the vapor flow path may contain the liquid-phase working medium 20 as long as it is a region where the gaseous working medium 20 mainly exists.

[0085] As shown in FIG. 2, the wick 30 may be provided at a position in the internal space of the housing 10 in contact with the second inner surface 10b. In this case, the wick 30 is preferably joined to the second inner surface 10b. Examples of the joining method between the wick 30 and the second inner surface 10b include diffusion bonding, ultrasonic bonding, spot welding, and the like.

[0086] The wick 30 may be provided at a position in the internal space of the housing 10 away from the second inner surface 10b. In this case, a microchannel that functions as a liquid flow path for the liquid-phase working medium 20 may be provided between the wick 30 and the second inner surface 10b. The microchannel is preferably provided on the second inner surface 10b and in contact with the wick 30.

[0087] The wick 30 has a capillary structure capable of moving the liquid-phase working medium 20 by capillary force.

[0088] The capillary structure of the wick 30 may be a known structure used in conventional heat diffusion devices (for example, vapor chambers). Examples of such capillary structures include fine structures having irregularities such as pores, grooves, and protrusions, for example, porous structures, fibrous structures, groove structures, mesh structures, and the like.

[0089] The wick 30 functions as a liquid transport unit that sucks up and transports the liquid-phase working medium 20 by capillary force.

[0090] In the example shown in FIG. 2, the wick 30 functions as a liquid flow path mainly containing the liquid-phase working medium 20. Here, the liquid flow path may contain the gaseous working medium 20 as long as it is a region where the liquid-phase working medium 20 mainly exists.

[0091] The wick 30 is preferably planar.

[0092] The wick 30 is preferably composed of a porous body.

[0093] Examples of the porous body include a sintered body, a nonwoven fabric, a mesh, an etched porous plate, a fiber bundle, and the like.

[0094] Examples of the sintered body include a metal porous sintered body, a ceramic porous sintered body, and the like. Among them, a metal porous sintered body is preferable, and a porous sintered body of copper or nickel is more preferable.

[0095] Examples of the nonwoven fabric include a metal nonwoven fabric and the like. When the wick 30 is composed of a nonwoven fabric, it can be manufactured at low cost.

[0096] Examples of the mesh include a metal mesh, a resin mesh, and these meshes with a surface coating, and the like. Among them, a copper mesh, a stainless steel (SUS) mesh, or a polyester mesh is preferable. When the wick 30 is composed of a mesh, it can be manufactured at low cost.

[0097] The etched porous plate is manufactured, for example, by etching a flat metal plate. When the wick 30 is composed of the etched porous plate manufactured in this way, it has excellent flatness.

[0098] The fiber bundle is manufactured, for example, by linearly bundling a plurality of fibers. The fiber bundle functions as a liquid holding part that sucks up and holds the liquid-phase working medium 20 by capillary force, and also functions as a liquid transport part that transports the sucked-up liquid-phase working medium 20.

[0099] When the wick 30 is composed of a fiber bundle, it is preferably composed of a knitted fiber bundle. In a knitted fiber bundle in which a plurality of fibers are knitted, unevenness is likely to exist on the surface. Therefore, when the wick 30 is composed of a knitted fiber bundle, the liquid-phase working medium 20 is easily transported.

[0100] Examples of the fibers constituting the fiber bundle include metal wires such as copper, aluminum, and stainless steel, and non-metal wires such as carbon fibers and glass fibers. Among them, metal wires are preferred because of their high thermal conductivity. For example, a fiber bundle can be formed by bundling about 200 copper wires with a diameter of about 0.03 mm.

[0101] The dimension of the wick 30 in the thickness direction T is preferably 2 μm or more and 200 μm or less, more preferably 5 μm or more and 100 μm or less, and still more preferably 10 μm or more and 40 μm or less.

[0102] The dimension of the wick 30 in the thickness direction T is defined as the maximum dimension in the thickness direction T.

[0103] The dimension of the wick 30 in the thickness direction T may be the same throughout or may be different in part.

[0104] As shown in FIG. 2, the support column 40a is provided on the second inner surface 10b.

[0105] In the example shown in FIG. 2, the support column 40a is provided so as to protrude in the thickness direction T from the second inner surface 10b toward the first inner surface 10a.

[0106] The support column 40a may be integrated with the second inner surface 10b. That is, the support column 40a may be composed of the second inner surface 10b, here, a portion extending from the inner surface of the second sheet 12. In this case, the support column 40a is formed, for example, by performing etching, pressing, or the like on the second inner surface 10b, here, the inner surface of the second sheet 12.

[0107] In this specification, the integration of two elements means a state in which there is no interface between the elements, for example, a state in which the boundary between the elements cannot be discriminated.

[0108] The support column 40a may be joined to the second inner surface 10b. In this case, the support column 40a is formed, for example, by joining a columnar member to the second inner surface 10b, here the inner surface of the second sheet 12, by a joining method such as welding or diffusion bonding.

[0109] From the perspective of suppressing the complication of assembly and the increase in cost due to the increase in the number of parts, among the above-described aspects of the support column 40a, the aspect in which the support column 40a is integrated with the second inner surface 10b is preferable.

[0110] As shown in FIG. 2, the support column 40a penetrates through the wick 30 in the thickness direction T and reaches the first inner surface 10a.

[0111] Since the support column 40a provided on the second inner surface 10b reaches the first inner surface 10a, the first inner surface 10a and the second inner surface 10b are supported by the support column 40a, so that the housing 10 is supported from the inner space side by the support column 40a. Therefore, even when external pressure is applied to the housing 10, the vapor flow path between the wick 30 and the first inner surface 10a is less likely to be crushed, and the vapor flow path is ensured. As a result, the transmittance of the vapor-phase working medium 20 through the vapor flow path is ensured.

[0112] As a method for realizing the configuration in which the support column 40a penetrates through the wick 30 in the thickness direction T, for example, there are a method of previously providing a through hole penetrating in the thickness direction T in the wick 30 and then inserting the support column 40a into the through hole, a method of piercing the support column 40a into the wick 30 in the thickness direction T, and the like.

[0113] In the present embodiment, as shown in FIG. 2, when a plurality of support columns 40a are provided, among the plurality of support columns 40a, at least one support column 40a may penetrate through the wick 30 in the thickness direction T and reach the first inner surface 10a. That is, in the present embodiment, among the plurality of support columns 40a, all of the support columns 40a may penetrate through the wick 30 in the thickness direction T and reach the first inner surface 10a, or some of the support columns 40a may penetrate through the wick 30 in the thickness direction T and reach the first inner surface 10a.

[0114] In the present embodiment, among the plurality of support columns 40a, when some of the support columns 40a penetrate the wick 30 in the thickness direction T and reach the first inner surface 10a, the remaining support columns 40a may include support columns that do not penetrate the wick 30 in the thickness direction T, or may include support columns that penetrate the wick 30 in the thickness direction T but do not reach the first inner surface 10a.

[0115] As shown in FIG. 2, the support column 40a is in contact with the bellows surface 15a.

[0116] Since the support column 40a is in contact with the bellows surface 15a, the housing 10 is supported by the support column 40a from the inner space side. Therefore, even when external pressure is applied to the housing 10, the vapor flow path between the wick 30 and the first inner surface 10a is less likely to be crushed sufficiently. As a result, the transmittance of the gaseous working medium 20 through the vapor flow path is sufficiently ensured.

[0117] The support column 40a may be in contact with the tip of the convex portion 16a or a portion other than the tip of the convex portion 16a with respect to the bellows surface 15a.

[0118] The tip of the support column 40a or a portion other than the tip of the support column 40a may be in contact with the bellows surface 15a.

[0119] As shown in FIG. 2, the support column 40a is not fixed to the bellows surface 15a.

[0120] In this specification, the fact that the support column is not fixed to the bellows surface means a mode in which the support column is not integrated with the bellows surface, and a mode in which the support column is not fixed to the bellows surface by a method such as joining.

[0121] In this embodiment, as shown in FIG. 2, when a plurality of support columns 40a are provided, at least one of the plurality of support columns 40a may be in contact with the bellows surface 15a and not fixed to the bellows surface 15a. That is, in this embodiment, not all of the plurality of support columns 40a need to be in contact with the bellows surface 15a and not fixed to the bellows surface 15a, and some of the support columns 40a may be in contact with the bellows surface 15a and not fixed to the bellows surface 15a.

[0122] In this embodiment, when some of the plurality of support columns 40a are in contact with the bellows surface 15a and not fixed to the bellows surface 15a, the remaining support columns 40a do not have to be in contact with the bellows surface 15a.

[0123] As described above, in the vapor chamber 1A, since the support column 40a is in contact with the bellows surface 15a but not fixed to the bellows surface 15a, even if the bellows structure of the bellows surface 15a expands and contracts, the support column 40a and the bellows surface 15a can change their relative positions to each other. Therefore, the expansion and contraction movement of the bellows structure of the bellows surface 15a is not hindered by the support column 40a.

[0124] Therefore, according to the vapor chamber 1A, it is possible to realize a heat dissipation device in which the expansion and contraction movement of the bellows structure is not hindered by the support column 40a that supports the housing 10 from the inner space side. Therefore, even if the support column 40a is provided, the vapor chamber 1A can be freely deformed by utilizing the expansion and contraction of the bellows structure.

[0125] Furthermore, in the vapor chamber 1A, since the support column 40a is provided on the second inner surface 10b so as to penetrate the wick 30 in the thickness direction T, it is not necessary to provide the support column 40a on the bellows surface 15a and the wick 30 where its installation is difficult. Therefore, for example, when attempting to thin the vapor chamber 1A, even if the bellows surface 15a has a fine bellows structure with a small height and pitch in order to suppress the thickness of the bellows structure while ensuring its stretchability, the difficulty of providing the support column 40a on the bellows surface 15a can be avoided. Also, in the vapor chamber 1A, since it is not necessary to provide the support column 40a on the wick 30, it is possible to avoid the difficulty of selecting a member that can have an appropriate specification (for example, pore diameter, porosity, etc.) that does not significantly affect the heat transport capacity of the vapor chamber 1A while providing the support column 40a.

[0126] FIG. 3 is a schematic plan view showing an example of a state of a part of the arrangement region of the wick and the support column constituting the heat diffusion device according to Embodiment 1 of the present invention as viewed from the thickness direction.

[0127] In the example shown in FIG. 3, a plurality of support columns 40a are provided.

[0128] As shown in FIG. 3, when viewed from the thickness direction T, the plurality of support columns 40a may be arranged in a lattice (matrix) pattern, may be arranged in a staggered pattern, or may be arranged in other arrangements.

[0129] As shown in FIG. 3, when viewed from the thickness direction T, the plurality of support columns 40a may be evenly provided such that the center-to-center distance (pitch) between adjacent support columns 40a in the plane direction is constant throughout, or may be unevenly provided such that the center-to-center distance between adjacent support columns 40a in the plane direction is not constant at least in part.

[0130] As shown in FIG. 3, when viewed from the thickness direction T, the plurality of support columns 40a may be provided over the entire second inner surface 10b, or may be provided on a part of the second inner surface 10b.

[0131] Examples of the constituent material of the support column 40a include metals, resins, ceramics, mixtures or laminates of two or more of these, and the like.

[0132] The constituent material of the support column 40a is preferably the same as the constituent material of the housing 10, here, the constituent material of the second sheet 12 where the support column 40a is provided, but it may be different from the constituent material of the second sheet 12.

[0133] As shown in FIGS. 2 and 3, when a plurality of support columns 40a are provided, the constituent materials of the plurality of support columns 40a may be the same as each other, may be different from each other, or may be partially different.

[0134] The support column 40a may be composed of a single layer or may be composed of a plurality of layers.

[0135] Examples of the planar shape of the support column 40a when viewed from the thickness direction T include polygons such as triangles and rectangles, circles, ellipses, shapes combining these, and the like.

[0136] As shown in FIGS. 2 and 3, when a plurality of support columns 40a are provided, the planar shapes of the plurality of support columns 40a may be the same as each other, may be different from each other, or may be partially different.

[0137] Examples of the cross-sectional shape of the support column 40a when viewed from the surface direction include polygons such as rectangles. The cross-sectional shape of the support column 40a may be a shape in which the dimensions in the surface direction are constant from the second inner surface 10b side to the first inner surface 10a side, or may be a tapered shape in which the dimensions in the surface direction become smaller as it goes from the second inner surface 10b side to the first inner surface 10a side.

[0138] As shown in FIGS. 2 and 3, when a plurality of support columns 40a are provided, the cross-sectional shapes of the plurality of support columns 40a may be the same as each other, may be different from each other, or may be partially different.

[0139] The dimension of the column 40a in the plane direction (for example, in FIGS. 2 and 3, the dimension in the length direction L) is converted into the equivalent diameter of a circle of the cross section along the plane direction at the end in the thickness direction T of the column 40a, and is, for example, 100 μm or more and 2000 μm or less, preferably 300 μm or more and 1000 μm or less. When the dimension of the column 40a in the plane direction increases, even if an external pressure is applied to the housing 10, the vapor flow path between the wick 30 and the first inner surface 10a is less likely to be crushed. When the dimension of the column 40a in the plane direction decreases, the vapor flow path between the wick 30 and the first inner surface 10a is likely to be widely secured.

[0140] As shown in FIGS. 2 and 3, when a plurality of columns 40a are provided, the dimensions of the plurality of columns 40a in the plane direction may be the same as each other, may be different from each other, or may be partially different.

[0141] As shown in FIGS. 2 and 3, when a plurality of columns 40a are provided, the dimensions of the plurality of columns 40a in the thickness direction T may be the same as each other, may be different from each other, or may be partially different.

[0142] The dimensions, shapes, numbers, arrangements, etc. of the column 40a may be different from the examples shown in FIGS. 2 and 3 in an actual product.

[0143] The vapor chamber 1A operates as follows.

[0144] In the vapor chamber 1A, the liquid-phase working medium 20 evaporates by absorbing heat from the heat source HS in the wick 30 (liquid flow path) existing in the region near the evaporation section (heat source HS), and changes into the gas-phase working medium 20. Then, the gas-phase working medium 20 generated in the evaporation section passes through the vapor flow path between the wick 30 and the first inner surface 10a, and moves to a region away from the evaporation section, for example, the periphery of the end portion on the opposite side of the evaporation section in the length direction L of the vapor flow path, where it is cooled and changes into the liquid-phase working medium 20. Hereinafter, the portion where the gas-phase working medium 20 condenses and changes into the liquid-phase working medium 20 is referred to as the condensation section. The condensation section is likely to be located in a region away from the evaporation section, for example, the periphery of the end portion on the opposite side of the evaporation section in the length direction L of the internal space of the housing 10. Then, the liquid-phase working medium 20 generated in the condensation section is recovered by the wick 30 and then transported to the evaporation section.

[0145] In the vapor chamber 1A, by repeating the above process, the working medium 20 circulates while undergoing a gas-liquid phase change. At this time, the heat from the heat source HS is absorbed as the latent heat of evaporation that changes the liquid-phase working medium 20 into the gas-phase working medium 20 in the evaporation section, and then released as the latent heat of condensation that changes the gas-phase working medium 20 into the liquid-phase working medium 20 in the condensation section (for example, a region away from the evaporation section). In this way, the vapor chamber 1A operates independently without the need for external power, and furthermore, by utilizing the latent heat of evaporation and the latent heat of condensation of the working medium 20, the heat from the heat source HS can be diffused two-dimensionally at high speed.

[0146] In the vapor chamber 1A, in order to promote the evaporation of the liquid-phase working medium 20, the internal space of the housing 10 may be depressurized. In this case, the housing 10 is pressured in a direction where the internal space is crushed by the atmospheric pressure. In particular, when attempting to make the vapor chamber 1A thinner, since it is required to reduce the thicknesses of the first sheet 11 and the second sheet 12, when the housing 10 receives the above-described pressure, the internal space of the housing 10 becomes even more likely to be crushed. On the other hand, in the vapor chamber 1A, since the support column 40a that supports the housing 10 from the internal space side is provided, even when the housing 10 receives the above-described pressure, the internal space of the housing 10 is less likely to be crushed. Further, as described above, in the vapor chamber 1A, even when the support column 40a that supports the housing 10 from the internal space side is provided, the expansion and contraction movement of the bellows structure of the bellows surface 15a is not hindered by the support column 40a.

[0147] <Embodiment 2> In the heat dissipation device according to Embodiment 2 of the present invention, the bellows surface includes a convex portion whose tip contacts the support column in the thickness direction. The heat dissipation device according to Embodiment 2 of the present invention is the same as the heat dissipation device according to Embodiment 1 of the present invention except for the above points.

[0148] FIG. 4 is a schematic cross-sectional view showing an example of the internal structure of the heat dissipation device according to Embodiment 2 of the present invention.

[0149] In the vapor chamber 1B shown in FIG. 4, the bellows surface 15a includes a convex portion 16a whose tip contacts the support column 40a in the thickness direction T. That is, in the vapor chamber 1B, there is a support column 40a that contacts the tip of the convex portion 16a in the thickness direction T.

[0150] In the vapor chamber 1B, since the support column 40a contacts the tip of the convex portion 16a in the thickness direction T, the support column 40a can effectively support the housing 10 from the internal space side without hindering the expansion and contraction movement of the bellows structure of the bellows surface 15a.

[0151] As shown in FIG. 4, it is preferable that the bellows surface 15a includes a convex portion 16a whose tip contacts the tip of the support column 40a in the thickness direction T. In this case, the support column 40a can support the housing 10 more effectively from the inner space side.

[0152] On the other hand, while the support column 40a serves to secure the vapor flow path between the wick 30 and the first inner surface 10a by supporting the housing 10 from the inner space side, it can reduce the heat transport capacity by inhibiting the flow of the gaseous working medium 20 in the vapor flow path and the flow of the liquid-phase working medium 20 in the wick 30. Therefore, from the perspective of heat transport capacity, it is not the case that the more support columns 40a there are, the more effective it is.

[0153] From the above, in the present embodiment, as shown in FIG. 4, when there are a plurality of convex portions 16a, it is sufficient that the support columns 40a are individually provided at positions where they contact the tips of at least one of the convex portions 16a in the thickness direction T. In the present embodiment, from the perspective of effectively supporting the housing 10 from the inner space side, the support columns 40a may be individually provided at positions where they contact the tips of all the convex portions 16a in the thickness direction T. Alternatively, in the present embodiment, from the perspective of suppressing a decrease in heat transport capacity, the support columns 40a do not necessarily have to be individually provided at positions where they contact the tips of all the convex portions 16a in the thickness direction T. More specifically, the support columns 40a do not necessarily have to be individually provided at positions where they contact the tips of some of the convex portions 16a in the thickness direction T.

[0154] Further, in the present embodiment, as shown in FIG. 4, when a plurality of support columns 40a are provided, at least one of the plurality of support columns 40a only needs to individually contact the tip of each convex portion 16a in the thickness direction T. That is, in the present embodiment, all of the plurality of support columns 40a may individually contact the tip of each convex portion 16a in the thickness direction T, or some of the support columns 40a may individually contact the tip of each convex portion 16a in the thickness direction T.

[0155] <Embodiment 3> In the heat diffusion device according to Embodiment 3 of the present invention, the bellows surface includes convex portions with flat tips. The heat diffusion device according to Embodiment 3 of the present invention is the same as the heat diffusion devices according to Embodiments 1 and 2 of the present invention except for the above points.

[0156] FIG. 5 is a schematic cross-sectional view showing an example of the internal structure of the heat diffusion device according to Embodiment 3 of the present invention.

[0157] In the vapor chamber 1C shown in FIG. 5, the bellows surface 15b includes convex portions 16b with flat tips.

[0158] In the vapor chamber 1C, since the bellows surface 15b includes convex portions 16b with flat tips, when the support column 40a contacts the tip of the convex portion 16b as shown in FIG. 5, the contact area between the support column 40a and the convex portion 16b becomes large. Therefore, the housing 10 is stably supported from the inner space side by the support column 40a. Further, in the vapor chamber 1C, since the contact area between the support column 40a and the convex portion 16b is large, even if the bellows structure of the bellows surface 15b expands and contracts and the positional relationship between the support column 40a and the convex portion 16b changes, the state where the support column 40a contacts the tip of the convex portion 16b is likely to be maintained. As a result, the housing 10 is stably supported from the inner space side by the support column 40a.

[0159] The tip of the convex portion 16b that is flat may have a shape that is substantially flat, such as a completely flat shape like a mirror surface, or a shape having roughness.

[0160] In the present embodiment, as shown in FIG. 5, when there are a plurality of convex portions 16b, it is sufficient that the tip of at least one of the plurality of convex portions 16b is flat. That is, in the present embodiment, the tips of all of the plurality of convex portions 16b may be flat, or the tips of some of the convex portions 16b may be flat.

[0161] The bellows surface 15b includes concave portions 17b with flat tips.

[0162] When there are a plurality of recesses 17b as shown in Fig. 5, the bottom end of at least one of the plurality of recesses 17b may be flat. That is, among the plurality of recesses 17b, the bottom ends of all the recesses 17b may be flat, or the bottom ends of some of the recesses 17b may be flat.

[0163] Regarding the convex portion 16b and the concave portion 17b adjacent to each other in the plane direction (in Fig. 5, the length direction L), the dimension in the plane direction of the tip (flat portion) of the convex portion 16b and the dimension in the plane direction of the bottom end (flat portion) of the concave portion 17b may be the same as each other, or may be different from each other.

[0164] Regarding the convex portion 16b and the concave portion 17b adjacent to each other in the plane direction, when the dimension in the plane direction of the tip of the convex portion 16b and the dimension in the plane direction of the bottom end of the concave portion 17b are different from each other, the dimension in the plane direction of the tip of the convex portion 16b may be smaller than the dimension in the plane direction of the bottom end of the concave portion 17b, or may be larger.

[0165] The aspect in which the bellows surface includes a convex portion with a flat tip is not limited to the example shown in Fig. 5.

[0166] Fig. 6 is a schematic cross-sectional view showing another example of the internal structure of the heat diffusion device according to Embodiment 3 of the present invention.

[0167] In the vapor chamber 1C' shown in Fig. 6, the bellows surface 15c includes a convex portion 16c with a flat tip. On the other hand, at the bottom end of the concave portion 17c in the bellows surface 15c, it is not flat.

[0168] Regarding the effects of the convex portion 16c in the vapor chamber 1C', the aspect when there are a plurality of convex portions 16c, and the aspect when there are a plurality of concave portions 17c, except that the bottom end of the concave portion 17c is not flat, is the same as that of the vapor chamber 1C described above.

[0169] <Embodiment 4> In the heat diffusion device according to Embodiment 4 of the present invention, a gap is provided between the wick and the support column in a plane direction perpendicular to the thickness direction. The heat diffusion device according to Embodiment 4 of the present invention is the same as the heat diffusion devices according to Embodiments 1 to 3 of the present invention except for the above point.

[0170] FIG. 7 is a schematic cross-sectional view showing an example of the internal structure of the heat diffusion device according to Embodiment 4 of the present invention.

[0171] In the vapor chamber 1D shown in FIG. 7, a gap 50 is provided between the wick 30 and the support column 40a in the plane direction.

[0172] In the vapor chamber 1D, when the bellows structure of the bellows surface 15a expands and contracts, the positional relationship between the wick 30 and the support column 40a in the plane direction changes. In the vapor chamber 1D, since a gap 50 is provided between the wick 30 and the support column 40a in the plane direction, the change in the positional relationship between the wick 30 and the support column 40a in the plane direction is absorbed by the gap 50, so that a load on the wick 30 and the support column 40a is suppressed.

[0173] In the present embodiment, when a plurality of support columns 40a are provided as shown in FIG. 7, for at least one of the plurality of support columns 40a, a gap 50 may be provided between the support column 40a and the wick 30 in the plane direction. That is, in the present embodiment, for all of the plurality of support columns 40a, a gap 50 may be provided between the support column 40a and the wick 30 in the plane direction, or for some of the support columns 40a, a gap 50 may be provided between the support column 40a and the wick 30 in the plane direction.

[0174] FIG. 8 is a schematic plan view showing an example of a state in which a part of the arrangement region of the wick and the support column constituting the heat diffusion device according to Embodiment 4 of the present invention is viewed from the thickness direction. FIG. 9 is a schematic plan view showing another example of a state in which a part of the arrangement region of the wick and the support column constituting the heat diffusion device according to Embodiment 4 of the present invention is viewed from the thickness direction.

[0175] When the vapor chamber 1D is deformed, the positional relationship between the wick 30 and the support column 40a changes in the expansion and contraction direction of the bellows structure of the bellows surface 15a (in FIGS. 7, 8, and 9, the length direction L). Therefore, the gap 50 is preferably large in the expansion and contraction direction of the bellows structure among the surface directions.

[0176] In this specification, the expansion and contraction direction of the bellows structure is the direction in which the convex portions and concave portions constituting the bellows structure are arranged (here, the surface direction). For example, in the bellows structure formed by folding a sheet into mountain folds and valley folds, it means the direction perpendicular to the mountain fold line and the valley fold line when viewed from the thickness direction.

[0177] As shown in FIG. 8, when viewed from the thickness direction T, the gap 50 may be provided with a uniform size around the support column 40a. In this case, if the gap 50 becomes larger as a whole in the surface direction so that the change in the positional relationship between the wick 30 and the support column 40a is easily absorbed by the gap 50, the liquid flow path may become smaller due to the reduction of the arrangement area of the wick 30, or the vapor flow path may become smaller due to the reduction of the arrangement area of the support column 40a, resulting in a possible decrease in the heat transport capacity.

[0178] On the other hand, as shown in FIG. 9, when viewed from the thickness direction T, the gap 50 is preferably provided with an uneven size around the support column 40a so as to be relatively long in the expansion and contraction direction of the bellows structure among the surface directions (in FIG. 9, the length direction L). More specifically, as shown in FIG. 9, when viewed from the thickness direction T, the gap 50 is in the expansion and contraction direction of the bellows structure among the surface directions (in FIG. 9, the length direction L), and is preferably provided with an uneven size around the support column 40a so as to be longer than the direction perpendicular to the expansion and contraction direction of the bellows structure (in FIG. 9, the width direction W). That is, the distance between the inner peripheral end and the outer peripheral end of the gap 50 is preferably longer in the expansion and contraction direction of the bellows structure than in the direction perpendicular to the expansion and contraction direction of the bellows structure. In this case, while the decrease in the heat transport capacity is suppressed, the change in the positional relationship between the wick 30 and the support column 40a is easily and effectively absorbed by the gap 50.

[0179] When a plurality of support columns 40a are provided as shown in FIGS. 8 and 9, among the plurality of support columns 40a, the gaps 50 may be provided with equal sizes around all the support columns 40a, or the gaps 50 may be provided with unequal sizes around all the support columns 40a. Alternatively, among the plurality of support columns 40a, the gaps 50 may be provided with equal sizes around some of the support columns 40a, and the gaps 50 may be provided with unequal sizes around the remaining support columns 40a.

[0180] <Embodiment 5> In the heat diffusion device according to Embodiment 5 of the present invention, the tip of the support column is rounded. The heat diffusion device according to Embodiment 5 of the present invention is the same as the heat diffusion devices according to Embodiments 1 to 4 of the present invention except for the above points.

[0181] FIG. 10 is a schematic cross-sectional view showing an example of the internal structure of the heat diffusion device according to Embodiment 5 of the present invention.

[0182] In the vapor chamber 1E shown in FIG. 10, the tip of the support column 40b is rounded.

[0183] In the vapor chamber 1E, when the bellows structure of the bellows surface 15a expands and contracts, the positional relationship between the support column 40b and the bellows surface 15a changes. In the vapor chamber 1E, since the tip of the support column 40b is rounded, when the positional relationship between the support column 40b and the bellows surface 15a changes, the bellows surface 15a is less likely to be caught by the tip of the support column 40b, so that the expansion and contraction movement of the bellows structure is less likely to be inhibited by the support column 40b. Further, in the vapor chamber 1E, since the tip of the support column 40b is rounded, when the positional relationship between the support column 40b and the bellows surface 15a changes, the bellows surface 15a is less likely to be damaged by the tip of the support column 40b, so that the housing 10 is less likely to be damaged (for example, it is less likely to have holes or tears).

[0184] The rounded shape of the tip of the support column 40b may be, for example, hemispherical or a shape other than hemispherical as long as it can be said to be a shape substantially composed of a curve.

[0185] In this embodiment, as shown in FIG. 10, when a plurality of support columns 40b are provided, at least one of the plurality of support columns 40b may have a rounded tip. That is, in this embodiment, the tips of all of the plurality of support columns 40b may be rounded, or the tips of some of the support columns 40b may be rounded.

[0186] Regarding at least one of the plurality of support columns 40b whose tips are rounded, the shape of the roundness of each tip may be the same as each other, may be different from each other, or may be partially different.

[0187] <Embodiment 6> In the heat diffusion device according to Embodiment 6 of the present invention, the tip of the support column is flat. The heat diffusion device according to Embodiment 6 of the present invention is the same as the heat diffusion devices according to Embodiments 1 to 4 of the present invention except for the above point.

[0188] FIG. 11 is a schematic cross-sectional view showing an example of the internal structure of the heat diffusion device according to Embodiment 6 of the present invention.

[0189] In the vapor chamber 1F shown in FIG. 11, the tip of the support column 40c is flat.

[0190] In the vapor chamber 1F, since the tip of the support column 40c is flat, when the support column 40c contacts the bellows surface 15a, the housing 10 is stably supported by the support column 40c from the internal space side.

[0191] In this embodiment, as shown in FIG. 11, when a plurality of support columns 40c are provided, at least one of the plurality of support columns 40c may have a flat tip. That is, in this embodiment, the tips of all of the plurality of support columns 40c may be flat, or the tips of some of the support columns 40c may be flat.

[0192] As shown in FIG. 11, it is preferable that the corners of the tips of the support columns 40c have a chamfered shape.

[0193] In the example shown in FIG. 11, the corners at the tips of the support columns 40c have a chamfered shape.

[0194] In the vapor chamber 1F, when the bellows structure of the bellows surface 15a expands and contracts, the positional relationship between the support column 40c and the bellows surface 15a changes. In the vapor chamber 1F, since the corners at the tips of the support columns 40c have a chamfered shape, when the positional relationship between the support column 40c and the bellows surface 15a changes, it becomes difficult for the bellows surface 15a to catch on the corners at the tips of the support columns 40c. Therefore, it becomes difficult for the expansion and contraction movement of the bellows structure to be inhibited by the support column 40c. Further, in the vapor chamber 1F, since the corners at the tips of the support columns 40c have a chamfered shape, when the positional relationship between the support column 40c and the bellows surface 15a changes, it becomes difficult for the bellows surface 15a to be damaged by the corners at the tips of the support columns 40c. Thus, it becomes difficult for the housing 10 to be damaged (for example, it becomes difficult for holes to open or for it to tear).

[0195] When a plurality of support columns 40c are provided as shown in FIG. 11, it is preferable that at least one of the corners at the tips of the plurality of support columns 40c has a chamfered shape. In this case, among the plurality of support columns 40c, the corners at the tips of all the support columns 40c may have a chamfered shape, or the corners at the tips of some of the support columns 40c may have a chamfered shape.

[0196] When at least one of the corners at the tips of the plurality of support columns 40c has a chamfered shape, for at least one support column 40c whose corner at the tip has a chamfered shape, the shapes of the corners at the respective tips may be the same as each other, may be different from each other, or may be partially different.

[0197] The aspect in which the tip of the support column is flat and the corners at the tip of the support column have a chamfered shape is not limited to the example shown in FIG. 11.

[0198] FIG. 12 is a schematic cross-sectional view showing another example of the internal structure of the heat diffusion device according to Embodiment 6 of the present invention.

[0199] In the vapor chamber 1F' shown in FIG. 12, the tip of the support column 40d is flat.

[0200] In the example shown in FIG. 12, the corners of the tip of the support column 40d have a chamfered shape.

[0201] Regarding the function and effect of the support column 40d in the vapor chamber 1F' and the aspect when a plurality of support columns 40d are provided, they are the same as those of the vapor chamber 1F described above.

[0202] In the heat dissipation device according to Embodiment 6 of the present invention, when the corners of the tip of the support column have a chamfered shape, the chamfered shape is not limited to the examples shown in FIGS. 11 and 12, and other shapes may be used.

[0203] <Embodiment 7> In the heat dissipation device according to Embodiment 7 of the present invention, the support column is longer in the expansion and contraction direction of the bellows structure than in the direction perpendicular to the expansion and contraction direction of the bellows structure among the plane directions perpendicular to the thickness direction. The heat dissipation device according to Embodiment 7 of the present invention is the same as the heat dissipation devices according to Embodiments 1 to 6 of the present invention except for the above point.

[0204] FIG. 13 is a schematic plan view showing an example of a state in which a part of the arrangement region of the wick and the support column constituting the heat dissipation device according to Embodiment 7 of the present invention is viewed from the thickness direction.

[0205] As shown in FIG. 13, the support column 40e has a rectangular planar shape when viewed from the thickness direction T, and is longer in the expansion and contraction direction of the bellows structure (length direction L in FIG. 13) than in the direction perpendicular to the expansion and contraction direction of the bellows structure (width direction W in FIG. 13) among the plane directions.

[0206] FIG. 14 is a schematic plan view showing another example of a state in which a part of the arrangement region of the wick and the support column constituting the heat dissipation device according to Embodiment 7 of the present invention is viewed from the thickness direction.

[0207] As shown in FIG. 14, the support column 40f has an elliptical planar shape when viewed from the thickness direction T, and among the planar directions, in the expansion and contraction direction of the bellows structure (in FIG. 14, the length direction L), it is longer than the direction perpendicular to the expansion and contraction direction of the bellows structure (in FIG. 14, the width direction W).

[0208] FIG. 15 is a schematic plan view showing still another example of a state in which a part of the arrangement region of the wick and the support column constituting the heat diffusion device according to Embodiment 7 of the present invention is viewed from the thickness direction.

[0209] As shown in FIG. 15, the support column 40g has an oval planar shape when viewed from the thickness direction T, and among the planar directions, in the expansion and contraction direction of the bellows structure (in FIG. 15, the length direction L), it is longer than the direction perpendicular to the expansion and contraction direction of the bellows structure (in FIG. 15, the width direction W).

[0210] In the vapor chamber having the configuration shown in FIG. 13, FIG. 14, or FIG. 15, when the bellows structure of the bellows surface (for example, the bellows surface 15a in FIG. 2) expands and contracts, the positional relationship between the support column (support column 40e, support column 40f, or support column 40g) and the bellows surface changes. In the vapor chamber having the configuration shown in FIG. 13, FIG. 14, or FIG. 15, since the support column is longer than the direction perpendicular to the expansion and contraction direction of the bellows structure in the expansion and contraction direction of the bellows structure in the planar direction (here, the length direction L), even if the positional relationship between the support column and the bellows surface changes, the state where the support column is in contact with the bellows surface is likely to be maintained. As a result, the housing 10 is stably supported from the inner space side by the support column.

[0211] The planar shape of the support column that is longer than the direction perpendicular to the expansion and contraction direction of the bellows structure in the expansion and contraction direction of the bellows structure in the planar direction is not limited to the above-described rectangle, ellipse, and oval, and other shapes may also be used.

[0212] In the present embodiment, as shown in FIGS. 13, 14, and 15, when a plurality of columns are provided, among the plurality of columns, at least one column may be longer in the expansion / contraction direction of the bellows structure than in the direction perpendicular to the expansion / contraction direction of the bellows structure in the plane direction. That is, in the present embodiment, among the plurality of columns, all the columns may be longer in the expansion / contraction direction of the bellows structure than in the direction perpendicular to the expansion / contraction direction of the bellows structure in the plane direction, or some of the columns may be longer in the expansion / contraction direction of the bellows structure than in the direction perpendicular to the expansion / contraction direction of the bellows structure in the plane direction.

[0213] [Electronic device] The electronic device of the present invention is characterized by including the heat dissipation device of the present invention.

[0214] Hereinafter, as an example of the electronic device of the present invention, an electronic device having the heat dissipation device of Embodiment 1 of the present invention will be described. The same applies to the electronic device having the heat dissipation device of other embodiments of the present invention.

[0215] FIG. 16 is a perspective schematic view showing an example of the electronic device of the present invention.

[0216] The electronic device 100 shown in FIG. 16 has a vapor chamber 1A.

[0217] In the example shown in FIG. 16, the vapor chamber 1A is bent using the bellows structure of the housing 10.

[0218] As shown in FIG. 16, the electronic device 100 preferably further has electronic components 110.

[0219] As shown in FIG. 16, the electronic components 110 are preferably provided on the outer surface of the housing 10 of the vapor chamber 1A. In this case, with the electronic components 110 as the heat source HS shown in FIG. 1, the vapor chamber 1A can function.

[0220] The electronic component 110 is preferably not provided on the outer surface facing the first inner surface 10a of the housing 10 of the vapor chamber 1A shown in FIG. 2, that is, on the outer surface facing the inner surface of the first sheet 11 provided with the bellows structure, and is preferably provided on the outer surface facing the second inner surface 10b, that is, on the outer surface facing the inner surface of the second sheet 12.

[0221] The electronic component 110 may be directly provided on the outer surface of the housing 10, or may be provided via other members such as an adhesive, a sheet, or a tape having high thermal conductivity.

[0222] When the electronic component 110 is provided on the outer surface of the housing 10, it is preferably overlapped with the evaporation part.

[0223] Examples of the electronic component 110 include heat generating elements such as a central processing unit (CPU), a light emitting diode (LED), and a power semiconductor.

[0224] As shown in FIG. 16, the electronic device 100 preferably further has a device housing 120.

[0225] In the example shown in FIG. 16, the vapor chamber 1A and the electronic component 110 are provided in the internal space of the device housing 120.

[0226] In the example shown in FIG. 16, similar to the vapor chamber 1A, the device housing 120 is also bent.

[0227] In the electronic device 100, even when the device housing 120 is bent, the vapor chamber 1A can be configured to be provided in the internal space of the device housing 120 in a state of being bent in the same manner as the device housing 120 by using the bellows structure of the housing 10.

[0228] The housing 10 and the equipment housing 120 are preferably joined via a joining member. More specifically, the outer surface of the housing 10 and the inner surface of the equipment housing 120 are preferably joined via a joining member. In this case, the adhesion between the housing 10 and the equipment housing 120 is improved.

[0229] The joining member for joining the housing 10 and the equipment housing 120 is preferably a heat-conductive member. In this case, heat from the heat source HS, here, heat from the electronic component 110, is easily conducted from the housing 10 to the equipment housing 120. That is, heat from the heat source HS, here, heat from the electronic component 110, is also easily diffused through the path from the housing 10 to the equipment housing 120.

[0230] Examples of the heat-conductive member include a heat-conductive tape, a heat-conductive adhesive, and the like.

[0231] As described above, the vapor chamber 1A operates independently without requiring external power, and further, by utilizing the latent heat of vaporization and the latent heat of condensation of the working medium 20, heat from the heat source HS, here, heat from the electronic component 110, can be diffused two-dimensionally at high speed. From the above, with the electronic device 100 having the vapor chamber 1A, heat dissipation can be effectively realized in the limited space inside the electronic device 100.

[0232] The following content is disclosed in this specification.

[0233] <1> A housing having a first inner surface and a second inner surface facing each other in the thickness direction and provided with an internal space, A working medium enclosed in the internal space of the housing, A wick provided at a position away from the first inner surface in the internal space of the housing, A support provided on the second inner surface and penetrating the wick in the thickness direction to reach the first inner surface, The first inner surface includes a bellows surface having a bellows structure, The above-mentioned support column is in contact with the bellows surface and is not fixed to the bellows surface. This is the characteristic of the heat diffusion device.

[0234] <2> The bellows surface of the heat diffusion device according to <1> includes a convex portion whose tip contacts the support column in the thickness direction.

[0235] <3> The bellows surface of the heat diffusion device according to <1> or <2> includes a convex portion whose tip is flat.

[0236] <4> In the plane direction perpendicular to the thickness direction, a gap is provided between the wick and the support column in the heat diffusion device according to any one of <1> to <3>.

[0237] <5> When viewed from the thickness direction, the gap is provided around the support column with an uneven size in the plane direction of the bellows structure, such that the gap is longer in the expansion and contraction direction of the bellows structure than in the direction perpendicular to the expansion and contraction direction of the bellows structure. This is the heat diffusion device according to <4>.

[0238] <6> The tip of the support column is rounded in the heat diffusion device according to any one of <1> to <5>.

[0239] <7> The tip of the support column is flat in the heat diffusion device according to any one of <1> to <5>.

[0240] <8> The corners of the tip of the support column have a chamfered shape in the heat diffusion device according to <7>.

[0241] <9> The support column is longer in the expansion and contraction direction of the bellows structure than in the direction perpendicular to the expansion and contraction direction of the bellows structure in the plane direction perpendicular to the thickness direction. This is the heat diffusion device according to any one of <1> to <8>.

[0242] <10> An electronic device comprising the heat diffusion device according to any one of <1> to <9>.

Industrial Applicability

[0243] The heat diffusion device of the present invention can be used for a wide range of applications in fields such as portable information terminals. The heat diffusion device of the present invention can be used, for example, to lower the temperature of a heat source such as a central processing unit and extend the usage time of an electronic device, and can be used in electronic devices such as smartphones, tablet terminals, notebook computers, game devices, and wearable devices. In particular, since the housing of the heat diffusion device of the present invention has a bellows structure and can be easily bent, it can be mounted on a hinge portion of an electronic device that requires bending, such as a foldable smartphone or notebook computer.

Explanation of Signs

[0244] 1A, 1B, 1C, 1C’, 1D, 1E, 1F, 1F’ Vapor chamber (heat diffusion device) 10 Housing 10a First inner surface 10b Second inner surface 11 First sheet 12 Second sheet 15a, 15b, 15c Bellows surface 16a, 16b, 16c Protrusion 17a, 17b, 17c Recess 20 Working medium 30 Wick 40a, 40b, 40c, 40d, 40e, 40f, 40g Support pillar 50 Gap 100 Electronic device 110 Electronic component 120 Equipment housing HS Heat source L Length direction T Thickness direction W Width direction

Claims

1. A housing having a first inner surface and a second inner surface facing each other in the thickness direction and provided with an internal space, A working medium enclosed in the internal space of the housing, A wick provided at a position away from the first inner surface in the internal space of the housing, A support column provided on the second inner surface and penetrating the wick in the thickness direction to reach the first inner surface, and comprising: The first inner surface includes a bellows surface having a bellows structure, The support column is in contact with the bellows surface and is not fixed to the bellows surface. A heat diffusion device characterized by this.

2. The bellows surface includes a convex portion whose tip contacts the support column in the thickness direction. The heat diffusion device according to Claim 1.

3. The bellows surface includes a convex portion whose tip is flat. The heat diffusion device according to Claim 1.

4. In the plane direction perpendicular to the thickness direction, a gap is provided between the wick and the support column. The heat diffusion device according to Claim 1.

5. When viewed from the thickness direction, the gap is provided around the support column with an uneven size in the plane direction, in the expansion and contraction direction of the bellows structure, and longer than the direction perpendicular to the expansion and contraction direction of the bellows structure. The heat diffusion device according to Claim 4.

6. The tip of the support column is rounded. The heat diffusion device according to Claim 1.

7. The tip of the support column is flat. The heat diffusion device according to Claim 1.

8. The corner of the tip of the support column has a chamfered shape. The heat diffusion device according to Claim 7.

9. The support column is longer in the expansion and contraction direction of the bellows structure than the direction perpendicular to the expansion and contraction direction of the bellows structure in the plane direction perpendicular to the thickness direction. The heat diffusion device according to Claim 1.

10. An electronic device comprising the heat diffusion device according to any one of Claims 1 to 9.

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