Thermal diffusion device and electronic device

Abstract

To provide a thermal diffusion device which enables improvement of a maximum heat transport amount in a structure in which a plurality of wick layers are laminated.SOLUTION: A thermal diffusion device 1 includes a housing 10 provided with an internal space, a working medium 20, and a wick 30. The wick 30 includes a first wick layer 31 and a second wick layer 32 in a thickness direction T. In the first wick layer 31, first through holes 41 are provided in the thickness direction T. The second wick layer 32 is provided with second through holes 42 in each of which a protruding part 52 getting close to a first inner surface 10a in the thickness direction T is located at a peripheral edge. When viewed in the thickness direction T, each second through hole 42 overlaps with the first through hole 41. When a distance between a first inner surface 10a side end 52a of the protruding part 52 located at the peripheral edge of the second through hole 42 and a second inner surface 10b is referred to as A1 and a distance between a second inner surface 10b side end P1 of the first through hole 41 and the second inner surface 10b is referred to as B1 in the thickness direction T, a relation of A1≥B1 is satisfied.SELECTED DRAWING: Figure 3

Description

[Technical field]

[0001] The present invention relates to a heat spreading device and an electronic device. [Background technology]

[0002] In recent years, the amount of heat generated has increased due to the high integration and high performance of elements. In addition, the heat density has increased due to the miniaturization of products. This situation is particularly noticeable in the field of mobile terminals such as smartphones and tablets. For these reasons, it is becoming increasingly important to take measures to dissipate heat.

[0003] Graphite sheets and the like are often used as materials for heat dissipation, but because their heat transport capacity is insufficient, the use of various heat diffusion devices that can diffuse heat is being considered.

[0004] As an example of such a heat diffusion device, Patent Document 1 discloses a vapor chamber in which three or more wicks are stacked in the internal space of a housing. [Prior art documents] [Patent documents]

[0005] [Patent Document 1] International Publication No. 2022 / 051958 Summary of the Invention [Problem to be solved by the invention]

[0006] In the vapor chamber, it is required to improve the maximum heat transport amount in order to diffuse more heat. As a method for improving the maximum heat transport amount of the vapor chamber, for example, it is considered to increase the volume of the liquid flow path through which the liquid phase working medium passes in the wick, specifically, to increase the cross-sectional area of ​​the region through which the liquid flow path passes through the wick.

[0007] In contrast, in the vapor chamber described in Patent Document 1, the wicks are stacked to increase the cross-sectional area of ​​the region through which the liquid flow path passes through the entire wick. However, in the vapor chamber described in Patent Document 1, the interface between adjacent wicks is not in contact with the vapor flow path through which the gas-phase working medium passes. Therefore, in the vapor chamber described in Patent Document 1, the liquid-phase working medium is unlikely to evaporate and change to a gas-phase working medium at the interface of the wick that is not in contact with the vapor flow path. Therefore, in the vapor chamber described in Patent Document 1, the driving force for driving the liquid-phase working medium, which is generated by changing the liquid-phase working medium to a gas-phase working medium, is likely to be weak throughout the entire wick, so that the liquid-phase working medium may be difficult to move.

[0008] For the above reasons, in the vapor chamber described in Patent Document 1, even if the cross-sectional area of ​​the area where the liquid flow path passes through the wick is increased by stacking the wicks, this may actually make it more difficult for the liquid phase working medium to move, making it difficult to improve the maximum heat transport rate.

[0009] The above problem is not limited to vapor chambers, but is a problem common to heat diffusion devices that are capable of diffusing heat using a similar structure to a vapor chamber.

[0010] The present invention has been made to solve the above problems, and aims to provide a heat spreading device capable of improving the maximum heat transport amount in a configuration in which multiple wick layers are stacked, and also aims to provide an electronic device having the heat spreading device. [Means for solving the problem]

[0011] The heat diffusion device of the present invention comprises a housing having a first inner surface and a second inner surface opposed to each other in a thickness direction and having an internal space, a working medium sealed in the internal space of the housing, and a wick provided in the internal space of the housing, the wick including a first wick layer and a second wick layer adjacent to the first wick layer on the second inner surface side in the thickness direction, the first wick layer having a first through hole in the thickness direction, the second wick layer having a second through hole having a protruding portion located on its periphery approaching the first inner surface in the thickness direction, the second through hole overlapping the first through hole when viewed from the thickness direction, and the distance between the end of the protruding portion located on the periphery of the second through hole on the first inner surface side and the second inner surface in the thickness direction is A1, and the distance between the end of the first through hole on the second inner surface side and the second inner surface in the thickness direction is B1, satisfying the relationship A1≧B1.

[0012] The electronic device of the present invention is characterized by comprising the heat spreading device of the present invention. Effect of the Invention

[0013] According to the present invention, it is possible to provide a heat spreading device capable of improving the maximum heat transport amount in a configuration in which a plurality of wick layers are stacked, and also to provide an electronic device having the heat spreading device. [Brief description of the drawings]

[0014] [Figure 1] FIG. 1 is a schematic perspective view showing an example of a heat diffusion device according to a first embodiment of the present invention. [Diagram 2] FIG. 2 is a schematic plan view showing an example of the internal structure of the heat spreading device according to the first embodiment of the present invention. [Diagram 3] FIG. 3 is a schematic cross-sectional view showing an example of a cross section of the heat spreading device shown in FIG. 2 taken along line a1-a2. [Figure 4] FIG. 4 is a schematic cross-sectional view showing an enlarged portion of the heat spreading device shown in FIG. [Diagram 5]FIG. 5 is a schematic cross-sectional view showing an example of a cross section of the heat spreading device according to the second embodiment of the present invention. [Figure 6] FIG. 6 is a schematic cross-sectional view showing an enlarged portion of the heat spreading device shown in FIG. [Figure 7] FIG. 7 is a schematic plan view showing an example of the internal structure of the heat spreading device according to the third embodiment of the present invention. [Figure 8] FIG. 8 is a schematic cross-sectional view showing an example of a cross section of the heat spreading device shown in FIG. 7 taken along line segment b1-b2. [Figure 9] FIG. 9 is a schematic cross-sectional view showing an enlarged portion of the heat spreading device shown in FIG. [Figure 10] FIG. 10 is a schematic cross-sectional view showing an example of a cross section of the heat spreading device shown in FIG. 7 taken along line segment b3-b4. [Figure 11] FIG. 11 is a schematic cross-sectional view showing an example of a cross section of the heat spreading device according to the fourth embodiment of the present invention. [Figure 12] FIG. 12 is a schematic cross-sectional view showing an enlarged portion of the heat spreading device shown in FIG. [Figure 13] FIG. 13 is a schematic cross-sectional view showing another example of the cross section of the heat spreading device according to the fourth embodiment of the present invention. [Figure 14] FIG. 14 is a schematic cross-sectional view showing an example of a cross section of the heat spreading device according to the fifth embodiment of the present invention. [Figure 15] FIG. 15 is a schematic cross-sectional view showing an enlarged portion of the heat spreading device shown in FIG. [Figure 16] FIG. 16 is a schematic cross-sectional view showing an example of a cross section of a heat spreading device according to the sixth embodiment of the present invention. [Figure 17] FIG. 17 is a schematic cross-sectional view showing an enlarged portion of the heat spreading device shown in FIG. [Figure 18] FIG. 18 is a schematic perspective view showing an example of an electronic device of the present invention. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0015] The heat spreading device of the present invention and the electronic device of the present invention will be described below. Note that the present invention is not limited to the following configurations, and may be modified as appropriate without departing from the gist of the present invention. In addition, a combination of multiple individual preferred configurations described below also constitutes the present invention.

[0016] The following embodiments are merely examples, and it goes without saying that partial replacement or combination of the configurations shown in different embodiments is possible. In the second and subsequent embodiments, the description of the matters common to the first embodiment will be omitted, and the differences will be mainly described. In particular, the same effects and advantages due to the same configuration will not be mentioned one by one for each embodiment.

[0017] In the following description, unless there is a need to distinguish between the various embodiments, they will simply be referred to as the "heat spreading device of the present invention" and the "electronic device of the present invention."

[0018] In the following embodiments, a vapor chamber is shown as an example of the heat diffusion device of the present invention, which can also be applied to heat diffusion devices such as heat pipes.

[0019] The drawings shown below are schematic diagrams, and the dimensions, aspect ratio, and scale may differ from those of the actual product.

[0020] In this specification, unless otherwise specified, terms indicating the relationship between elements (e.g., "parallel", "perpendicular", etc.) and terms indicating the shape of elements not only mean the literal strict form, but also mean a range that is substantially equivalent, for example, a range that includes a difference of about a few percent.

[0021] [Heat diffusion device] The heat diffusion device of the present invention comprises a housing having a first inner surface and a second inner surface opposed to each other in a thickness direction and having an internal space, a working medium sealed in the internal space of the housing, and a wick provided in the internal space of the housing, the wick including a first wick layer and a second wick layer adjacent to the first wick layer on the second inner surface side in the thickness direction, the first wick layer having a first through hole in the thickness direction, the second wick layer having a second through hole having a protruding portion located on its periphery approaching the first inner surface in the thickness direction, the second through hole overlapping the first through hole when viewed from the thickness direction, and the distance between the end of the protruding portion located on the periphery of the second through hole on the first inner surface side and the second inner surface in the thickness direction is A1, and the distance between the end of the first through hole on the second inner surface side and the second inner surface in the thickness direction is B1, satisfying the relationship A1≧B1.

[0022] <Embodiment 1> In the heat diffusion device of embodiment 1 of the present invention, the first wick layer is located closest to the first inner surface in the thickness direction of the wick, and the second wick layer is located closest to the second inner surface in the thickness direction of the wick.

[0023] FIG. 1 is a schematic perspective view showing an example of a heat diffusion device according to a first embodiment of the present invention.

[0024] The vapor chamber (thermal diffusion device) 1 shown in FIG.

[0025] The housing 10 is sealed in an airtight state and has a hollow structure.

[0026] A heat source HS, which is a heat generating element, is provided on the outer surface of the housing 10.

[0027] The heat source HS may be, for example, an electronic component.

[0028] In this specification, the length direction, thickness direction, and width direction are respectively defined as directions L, T, and W as shown in Fig. 1 etc. The length direction L, thickness direction T, and width direction W are perpendicular to each other. Moreover, a direction perpendicular to the thickness direction T and including the length direction L and width direction W is defined as a surface direction.

[0029] The vapor chamber 1 is preferably planar as a whole. That is, the housing 10 is preferably planar as a whole.

[0030] In this specification, the term "planar" refers to a shape that includes a plate shape and a sheet shape, and means a shape in which the lengthwise dimension and widthwise dimension are considerably larger than the thicknesswise dimension, for example, a shape in which the lengthwise dimension and widthwise dimension are 10 times or more, preferably 100 times or more, the thicknesswise dimension.

[0031] The size of the vapor chamber 1 is not particularly limited.

[0032] The length L and width W of the vapor chamber 1 are preferably 5 mm or more and 500 mm or less, more preferably 20 mm or more and 300 mm or less, and further preferably 50 mm or more and 200 mm or less.

[0033] The length direction L and width direction W of the vapor chamber 1 may be the same or different.

[0034] The dimension of the vapor chamber 1 in the thickness direction T is preferably 50 μm or more and 500 μm or less.

[0035] The length direction L, thickness direction T, and width direction W dimensions of the vapor chamber 1 are defined as the maximum dimensions in the length direction L, thickness direction T, and width direction W, respectively.

[0036] The housing 10 is preferably composed of a first sheet 11 and a second sheet 12 whose outer edges are joined together. In this case, the first sheet 11 and the second sheet 12 may overlap so that their ends coincide with each other, or may overlap so that their ends are misaligned with each other.

[0037] Examples of a method for joining 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 sealing, etc. Among these, laser welding, resistance welding, and brazing are preferred.

[0038] The constituent material of the first sheet 11 and the second sheet 12 is not particularly limited as long as it has properties suitable for a vapor chamber, such as thermal conductivity, strength, flexibility, flexibility, etc. The constituent material of the first sheet 11 and the second sheet 12 is preferably a metal, such as copper, nickel, aluminum, magnesium, titanium, iron, or an alloy containing at least one of these metals as a main component, and is particularly preferably copper or aluminum.

[0039] The constituent materials of the first sheet 11 and the second sheet 12 may be the same as or different from each other.

[0040] When the first sheet 11 and the second sheet 12 are made of different materials, the first sheet 11 and the second sheet 12 can exhibit different functions. Such functions are not particularly limited, but examples thereof include a heat conduction function and an electromagnetic wave shielding function.

[0041] The shapes of the first sheet 11 and the second sheet 12 are not particularly limited. For example, the first sheet 11 may be a flat plate with a constant dimension in the thickness direction T, and the second sheet 12 may be a shape in which the outer edge portion has a larger dimension in the thickness direction T than the portion other than the outer edge portion. Alternatively, the first sheet 11 may be a flat plate with a constant dimension in the thickness direction T, and the second sheet 12 may be a shape in which the dimension in the thickness direction T is constant and the portion other than the outer edge portion is convex outward relative 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 the vapor chamber 1. In addition, other components can be placed in the recess in the outer edge portion of the housing 10.

[0042] The dimension in the thickness direction T of the first sheet 11 and the second sheet 12 is preferably 10 μm or more and 200 μm or less, more preferably 30 μm or more and 100 μm or less, and further preferably 40 μm or more and 60 μm or less.

[0043] The dimensions of the first sheet 11 and the second sheet 12 in the thickness direction T may be the same as each other or may be different from each other.

[0044] The dimensions of the first sheet 11 and the second sheet 12 in the thickness direction T may be the same throughout, or may differ partially.

[0045] The dimensions of the first sheet 11 and the second sheet 12 in the thickness direction T are each defined as the maximum dimensions in the thickness direction T.

[0046] 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, and shapes that are combinations of these. The planar shape of the housing 10 may be an L-shape, a C-shape, a stepped shape, or the like. The housing 10 may also be provided with a through hole in the thickness direction T. The planar shape of the housing 10 may be a shape according to the use of the vapor chamber 1, a shape according to the mounting location of the vapor chamber 1, or a shape according to other components present in the vicinity.

[0047] The size of the housing 10 is not particularly limited.

[0048] The length direction L and width direction W of the housing 10 are each preferably 5 mm or more and 500 mm or less, more preferably 20 mm or more and 300 mm or less, and even more preferably 50 mm or more and 200 mm or less.

[0049] The length direction L and width direction W dimensions of the housing 10 may be the same as each other or may be different from each other.

[0050] The dimension of the housing 10 in the thickness direction T is preferably 50 μm or more and 500 μm or less.

[0051] The dimensions of the housing 10 in the length direction L, thickness direction T, and width direction W are defined as the maximum dimensions in the length direction L, thickness direction T, and width direction W, respectively.

[0052] FIG. 1 illustrates an example in which housing 10 is made up of two sheets, first sheet 11 and second sheet 12, but housing 10 may be made up of one sheet or three or more sheets.

[0053] Fig. 2 is a schematic plan view showing an example of the internal structure of the heat diffusion device according to the first embodiment of the present invention. Fig. 3 is a schematic cross-sectional view showing an example of a cross section along the line a1-a2 of the heat diffusion device shown in Fig. 2. Fig. 4 is a schematic cross-sectional view showing an enlarged portion of the heat diffusion device shown in Fig. 3.

[0054] The vapor chamber 1 shown in FIGS. 2 and 3 includes a housing 10, a working medium 20, and a wick 30.

[0055] As shown in FIG. 3, the housing 10 has a first inner surface 10a and a second inner surface 10b that face each other in a thickness direction T.

[0056] In the example shown in Figure 3, the housing 10 is composed of a first sheet 11 and a second sheet 12, with the inner surface of the first sheet 11 corresponding to the first inner surface 10a of the housing 10 and the inner surface of the second sheet 12 corresponding to the second inner surface 10b of the housing 10.

[0057] An internal space is provided in the housing 10. More specifically, the housing 10 has an internal space surrounded by a first inner surface 10a and a second inner surface 10b.

[0058] As shown in FIG. 2, the housing 10 preferably has an evaporation part EP in its internal space.

[0059] The evaporation part EP is a part that evaporates the liquid-phase working medium 20 described below and changes it into a gas-phase working medium 20. More specifically, the evaporation part EP is a part of the internal space of the housing 10 that is in the vicinity of the heat source HS shown in FIG. 1 and corresponds to a part that is heated by the heat source HS.

[0060] The number of evaporation parts EP may be one or more depending on the number of heat sources HS as shown in Fig. 2. In other words, the outer surface of the housing 10 may be provided with one or more heat sources HS.

[0061] The heat source HS may be provided on the outer surface opposite the first inner surface 10a of the housing 10, in this case the outer surface of the first sheet 11, or on the outer surface opposite the second inner surface 10b of the housing 10, in this case the outer surface of the second sheet 12.

[0062] As shown in FIGS. 2 and 3, the working medium 20 is sealed in the internal space of the housing 10.

[0063] The working medium 20 is not particularly limited as long as it can undergo a gas-liquid phase change in the environment inside the housing 10. Examples of the working medium 20 include water, alcohols, and alternative fluorocarbons. The working medium 20 is preferably an aqueous compound, and among these, water is particularly preferable.

[0064] As shown in FIGS. 2 and 3, the wick 30 is provided in the internal space of the housing 10.

[0065] The wick 30 has a capillary structure that can move the liquid phase working medium 20 by capillary force.

[0066] The capillary structure of the wick 30 may be a known structure used in conventional heat diffusion devices (such as vapor chambers). Examples of such capillary structures include microstructures having irregularities such as pores, grooves, and protrusions, such as a porous structure, a fibrous structure, a groove structure, and a mesh structure.

[0067] The wick 30 functions as a liquid transport section that sucks up and transports the liquid phase working medium 20 by capillary force.

[0068] When viewed from the thickness direction T, the wick 30 is preferably provided continuously in the internal space of the housing 10. For example, when viewed from the thickness direction T, the wick 30 may be provided in the entire internal space of the housing 10, or may be provided in a part of the internal space of the housing 10.

[0069] The wick 30 is preferably made of a porous material.

[0070] Examples of the porous body include a sintered body, a nonwoven fabric, a mesh, an etched porous plate, and a fiber bundle.

[0071] Examples of the sintered body include a porous metal sintered body, a porous ceramic sintered body, etc. Among them, a porous metal sintered body is preferable, and a porous copper or nickel sintered body is more preferable.

[0072] An example of the nonwoven fabric is a metal nonwoven fabric. When the wick 30 is made of a nonwoven fabric, it can be produced at low cost.

[0073] Examples of the mesh include metal mesh, resin mesh, and surface-coated mesh of these meshes. Among them, copper mesh, stainless steel (SUS) mesh, and polyester mesh are preferable. When the wick 30 is made of a mesh, it can be produced at low cost.

[0074] The etched porous plate is produced, for example, by etching a flat metal plate. When the wick 30 is made of an etched porous plate produced in this manner, it has excellent flatness.

[0075] The fiber bundle is produced, for example, by bundling a plurality of fibers into a linear shape. The fiber bundle functions as a liquid retaining part that sucks up and retains the liquid-phase working medium 20 by capillary force, and also functions as a liquid transporting part that transports the sucked up liquid-phase working medium 20.

[0076] When the wick 30 is made of a fiber bundle, it is preferably made of a braided fiber bundle. A braided fiber bundle in which a plurality of fibers are woven is likely to have unevenness on the surface, so when the wick 30 is made of a braided fiber bundle, the liquid phase working medium 20 is easily transported.

[0077] Examples of the fibers constituting the fiber bundle include metal wires such as copper, aluminum, and stainless steel, and nonmetal wires such as carbon fiber and glass fiber. Among them, metal wires are preferred because of their high thermal conductivity. For example, a fiber bundle can be made by bundling about 200 copper wires with a diameter of about 0.03 mm.

[0078] 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 even more preferably 10 μm or more and 40 μm or less.

[0079] The dimension of the wick 30 in the thickness direction T may be the same throughout or may differ in some parts.

[0080] 3, the wick 30 includes a first wick layer 31 and a second wick layer 32 adjacent to the second inner surface 10b side of the first wick layer 31 in the thickness direction T. In this manner, the wick 30 has a configuration in which a plurality of wick layers including the first wick layer 31 and the second wick layer 32 are stacked in the thickness direction T.

[0081] 3, the first wick layer 31 is located closest to the first inner surface 10a in the thickness direction T of the wick 30. Furthermore, as shown in Fig. 3, the second wick layer 32 is located closest to the second inner surface 10b in the thickness direction T of the wick 30. That is, in the vapor chamber 1, the wick 30 has a configuration in which two wick layers, the first wick layer 31 and the second wick layer 32, are stacked in the thickness direction T.

[0082] As shown in FIG. 3, the region between the first wick layer 31 and the second inner surface 10b constitutes a liquid flow path that mainly contains the working medium 20 in a liquid phase.

[0083] The liquid flow path may contain the working medium 20 in a gas phase, so long as it is a region where the working medium 20 in a liquid phase is mainly present.

[0084] As described above, in the vapor chamber 1, the wick 30 exerts a capillary force on the liquid phase working medium 20 while forming a liquid flow path for the liquid phase working medium 20, thereby controlling the transport of the liquid phase working medium 20.

[0085] In the internal space of the housing 10, the region other than the liquid flow path constitutes a vapor flow path that mainly contains the gas phase working medium 20. In the example shown in Fig. 3, the region between the wick 30 and the first inner surface 10a, specifically, the region between the first wick layer 31 and the first inner surface 10a constitutes the vapor flow path that mainly contains the gas phase working medium 20.

[0086] The vapor flow path may contain the working medium 20 in a liquid phase, so long as it is a region where the working medium 20 in a vapor phase is said to be mainly present.

[0087] As shown in FIG. 3, in the thickness direction T, the distance between the wick 30 and the first inner surface 10a is preferably greater than the distance between the wick 30 and the second inner surface 10b. In other words, in the thickness direction T, the distance between the wick layer located closest to the first inner surface 10a of the wick 30 and the first inner surface 10a is preferably greater than the distance between the wick layer located closest to the second inner surface 10b of the wick 30 and the second inner surface 10b. In the example shown in FIG. 3, in the thickness direction T, the distance between the first wick layer 31 and the first inner surface 10a is greater than the distance between the second wick layer 32 and the second inner surface 10b. In this way, when the distance between the wick 30 and the first inner surface 10a is greater than the distance between the wick 30 and the second inner surface 10b in the thickness direction T, the region between the wick 30 and the first inner surface 10a is more likely to function as a steam flow path.

[0088] Each of the wick layers that make up the wick 30 will be described in detail below.

[0089] As shown in FIGS. 3 and 4, the first wick layer 31 is provided with first through holes 41 in the thickness direction T.

[0090] The first through holes 41 exert a capillary force on the working medium 20. That is, the working medium 20 moves inside the first through holes 41 due to the capillary force.

[0091] The cross-sectional shape of the first through hole 41 when viewed in a cross section perpendicular to the thickness direction T is not particularly limited, and examples thereof include polygons such as triangles and rectangles, circles, ellipses, and shapes combining these.

[0092] In the example shown in Figure 3, multiple first through holes 41 are provided, and when viewed in a cross section perpendicular to the thickness direction T, the cross-sectional shapes of the multiple first through holes 41 may be the same as each other, may be different from each other, or may be partially different.

[0093] The cross-sectional shape of the first through hole 41 when viewed in a cross section along the thickness direction T is not particularly limited, and may be, for example, a shape in which the diameter of the first through hole 41 (the dimension in the width direction W in FIGS. 3 and 4) decreases toward the first inner surface 10a as shown in Figures 3 and 4, or a shape in which the diameter of the first through hole 41 increases. Furthermore, the cross-sectional shape of the first through hole 41 when viewed in a cross section along the thickness direction T may be a shape in which the diameter of the first through hole 41 is constant toward the first inner surface 10a.

[0094] In the example shown in Figure 3, multiple first through holes 41 are provided, and when viewed in a cross section along the thickness direction T, the cross-sectional shapes of the multiple first through holes 41 may be the same as each other, may be different from each other, or may be partially different.

[0095] There is no particular limitation on the size of the first through hole 41. For example, there is no particular limitation on the dimension of the first through hole 41 in a planar direction (for example, the length direction L or the width direction W).

[0096] 3, a plurality of first through holes 41 are provided, and the sizes of the plurality of first through holes 41 may be the same as each other, may be different from each other, or may be partially different. For example, the dimensions of the plurality of first through holes 41 in a surface direction (e.g., length direction L or width direction W) may be the same as each other, may be different from each other, or may be partially different.

[0097] The size, shape, number, arrangement, etc. of the first through holes 41 may differ from the example shown in FIG. 3 in an actual product.

[0098] As shown in FIGS. 3 and 4, it is preferable that a protrusion 51 approaching the first inner surface 10a in the thickness direction T is located on the periphery of the first through hole 41.

[0099] The protrusion 51 is preferably located around the entire periphery of the first through-hole 41 .

[0100] The protrusion 51 may be located on a portion of the periphery of the first through-hole 41 .

[0101] 3, a plurality of protruding portions 51 are provided due to the provision of a plurality of first through holes 41, and it is preferable that all of the plurality of protruding portions 51 are located on the entire periphery of the first through hole 41. Of the plurality of protruding portions 51, some of the protruding portions 51 may be located on the entire periphery of the first through hole 41. In this manner, of the plurality of protruding portions 51, at least some of the protruding portions 51 may be located on the entire periphery of the first through hole 41.

[0102] 3, it is preferable that the protrusion 51 is not in contact with the first inner surface 10a in the thickness direction T. In other words, it is preferable that the protrusion 51 is separated from the first inner surface 10a in the thickness direction T.

[0103] The protruding portion 51 may be in contact with the first inner surface 10a in the thickness direction T.

[0104] 3, there are a plurality of protrusions 51, and it is preferable that all of the plurality of protrusions 51 are spaced apart from the first inner surface 10a in the thickness direction T. Of the plurality of protrusions 51, some of the protrusions 51 may be spaced apart from the first inner surface 10a in the thickness direction T. In this manner, of the plurality of protrusions 51, at least one protrusion 51 may be spaced apart from the first inner surface 10a in the thickness direction T.

[0105] The cross-sectional shape of the protrusions 51 when viewed along a cross section in the thickness direction T is not particularly limited, and may be a shape in which the distance between the inner surfaces of the protrusions 51 (the distance in the width direction W in Figs. 3 and 4) decreases toward the first inner surface 10a as shown in Figs. 3 and 4, or may be a shape in which the distance between the inner surfaces of the protrusions 51 increases. Furthermore, the cross-sectional shape of the protrusions 51 may be a shape in which the distance between the inner surfaces of the protrusions 51 is constant toward the first inner surface 10a.

[0106] The protruding portion 51 may be bent at the end on the first inner surface 10a side toward the first through hole 41 (inward) or toward the opposite side to the first through hole 41 (outward).

[0107] In the example shown in FIG. 3, there are multiple protrusions 51, and when viewed in a cross section along the thickness direction T, the cross-sectional shapes of the multiple protrusions 51 may be the same as each other, may be different from each other, or may be partially different.

[0108] There is no particular limitation on the size of the protrusion 51. For example, the dimension of the protrusion 51 in the thickness direction T may be larger than the dimension of the first through hole 41 in the planar direction (for example, the length direction L or the width direction W), may be smaller than the dimension of the first through hole 41 in the planar direction, or may be the same as the dimension of the first through hole 41 in the planar direction.

[0109] 3, there are multiple protrusions 51, but the sizes of the multiple protrusions 51 may be the same as each other, may be different from each other, or may be partially different. For example, the dimensions of the multiple protrusions 51 in the thickness direction T may be the same as each other, may be different from each other, or may be partially different.

[0110] The dimensions, shape, arrangement, etc. of the protrusion 51 in an actual product may differ from the example shown in FIG.

[0111] It should be noted that a protrusion may not be located on the periphery of the first through hole 41. Specifically, a protrusion approaching the first inner surface 10a or the second inner surface 10b in the thickness direction T may not be located on the periphery of the first through hole 41.

[0112] As shown in Figures 3 and 4, in addition to the first through hole 41, the first wick layer 31 may further have a through hole 41A that does not overlap with the second through hole 42 described later when viewed from the thickness direction T.

[0113] As shown in FIGS. 3 and 4, a protruding portion 51A approaching the second inner surface 10b in the thickness direction T may be located on the periphery of the through hole 41A.

[0114] It is preferable that the protrusion 51A is located around the entire periphery of the through hole 41A.

[0115] The protrusion 51A may be located on a part of the periphery of the through hole 41A.

[0116] In the example shown in Fig. 3, a plurality of protrusions 51A are provided due to the provision of a plurality of through holes 41A, but it is preferable that all of the plurality of protrusions 51A are located on the entire periphery of the through hole 41A. Of the plurality of protrusions 51A, some of the protrusions 51A may be located on the entire periphery of the through hole 41A. In this way, of the plurality of protrusions 51A, at least some of the protrusions 51A may be located on the entire periphery of the through hole 41A.

[0117] The cross-sectional shape of the protrusions 51A when viewed along a cross section in the thickness direction T is not particularly limited, and may be a shape in which the distance between the inner surfaces of the protrusions 51A (the distance in the width direction W in Figs. 3 and 4) decreases toward the second inner surface 10b as shown in Figs. 3 and 4, or may be a shape in which the distance between the inner surfaces of the protrusions 51A increases. Furthermore, the cross-sectional shape of the protrusions 51A may be a shape in which the distance between the inner surfaces of the protrusions 51A is constant toward the second inner surface 10b.

[0118] The protruding portion 51A may be bent at the end on the second inner surface 10b side toward the through hole 41A (inward) or toward the opposite side to the through hole 41A (outward).

[0119] In the example shown in FIG. 3, there are multiple protrusions 51A, and when viewed in a cross section along the thickness direction T, the cross-sectional shapes of the multiple protrusions 51A may be the same as each other, may be different from each other, or may be partially different.

[0120] The size of the protrusion 51A is not particularly limited. For example, the dimension of the protrusion 51A in the thickness direction T may be larger than the dimension of the through hole 41A in the surface direction (for example, the length direction L or the width direction W), may be smaller than the dimension of the through hole 41A in the surface direction, or may be the same as the dimension of the through hole 41A in the surface direction.

[0121] 3, there are multiple protrusions 51A, but the sizes of the multiple protrusions 51A may be the same as each other, may be different from each other, or may be partially different. For example, the dimensions of the multiple protrusions 51A in the thickness direction T may be the same as each other, may be different from each other, or may be partially different.

[0122] The dimensions, shape, arrangement, etc. of the protrusion 51A in an actual product may differ from the example shown in FIG.

[0123] As shown in Figures 3 and 4, in addition to the first through hole 41, the first wick layer 31 may further have a through hole 41B that does not overlap with the second through hole 42 described later when viewed from the thickness direction T.

[0124] 3 and 4, a protrusion may not be located on the periphery of the through hole 41B. Specifically, a protrusion approaching the first inner surface 10a or the second inner surface 10b in the thickness direction T may not be located on the periphery of the through hole 41B.

[0125] As shown in FIGS. 3 and 4, the second wick layer 32 is provided with second through holes 42 in the thickness direction T.

[0126] The second through holes 42 exert a capillary force on the working medium 20. That is, the working medium 20 moves inside the second through holes 42 due to the capillary force.

[0127] Other features of the second through hole 42 are similar to those of the first through hole 41.

[0128] As shown in FIGS. 3 and 4, a protrusion 52 is located on the periphery of the second through hole 42 and approaches the first inner surface 10a in the thickness direction T.

[0129] The protrusion 52 is preferably located around the entire periphery of the second through-hole 42 .

[0130] The protrusion 52 may be located on a portion of the periphery of the second through-hole 42 .

[0131] 3, a plurality of protruding portions 52 are provided due to the provision of a plurality of second through holes 42, and it is preferable that all of the plurality of protruding portions 52 are located on the entire periphery of the second through hole 42. Of the plurality of protruding portions 52, some of the protruding portions 52 may be located on the entire periphery of the second through hole 42. In this manner, of the plurality of protruding portions 52, at least some of the protruding portions 52 may be located on the entire periphery of the second through hole 42.

[0132] 3, it is preferable that the protrusion 52 does not contact the first inner surface 10a in the thickness direction T. In other words, it is preferable that the protrusion 52 is separated from the first inner surface 10a in the thickness direction T.

[0133] The protruding portion 52 may be in contact with the first inner surface 10a in the thickness direction T.

[0134] 3, there are a plurality of protrusions 52, and it is preferable that all of the plurality of protrusions 52 are separated from the first inner surface 10a in the thickness direction T. Of the plurality of protrusions 52, some of the protrusions 52 may be separated from the first inner surface 10a in the thickness direction T. In this manner, of the plurality of protrusions 52, at least one protrusion 52 may be separated from the first inner surface 10a in the thickness direction T.

[0135] The cross-sectional shape of the protrusions 52 when viewed in a cross section along the thickness direction T is not particularly limited, and may be a shape in which the distance between the inner surfaces of the protrusions 52 (the distance in the width direction W in Figs. 3 and 4) decreases toward the first inner surface 10a as shown in Figs. 3 and 4, or may be a shape in which the distance between the inner surfaces of the protrusions 52 increases. Furthermore, the cross-sectional shape of the protrusions 52 may be a shape in which the distance between the inner surfaces of the protrusions 52 is constant toward the first inner surface 10a.

[0136] The protrusion 52 may be bent at the end on the first inner surface 10a side toward the second through hole 42 (inward), or may be bent toward the opposite side to the second through hole 42 (outward).

[0137] In the example shown in FIG. 3, there are multiple protrusions 52, and when viewed in a cross section along the thickness direction T, the cross-sectional shapes of the multiple protrusions 52 may be the same as each other, may be different from each other, or may be partially different.

[0138] There is no particular limitation on the size of the protruding portion 52. For example, the dimension of the protruding portion 52 in the thickness direction T may be larger than the dimension of the second through hole 42 in the planar direction (for example, the length direction L or the width direction W), may be smaller than the dimension of the second through hole 42 in the planar direction, or may be the same as the dimension of the second through hole 42 in the planar direction.

[0139] 3, there are multiple protrusions 52, but the sizes of the multiple protrusions 52 may be the same as each other, may be different from each other, or may be partially different. For example, the dimensions of the multiple protrusions 52 in the thickness direction T may be the same as each other, may be different from each other, or may be partially different.

[0140] The dimensions, shape, arrangement, etc. of the protrusions 52 in an actual product may differ from the example shown in FIG.

[0141] As shown in Figures 3 and 4, in addition to the second through hole 42, the second wick layer 32 may further have a through hole 42A that does not overlap with the first through hole 41 when viewed from the thickness direction T.

[0142] As shown in FIGS. 3 and 4, a protruding portion 52A approaching the second inner surface 10b in the thickness direction T may be located on the periphery of the through hole 42A.

[0143] 3, the protrusion 52A is preferably in contact with the second inner surface 10b in the thickness direction T. In this case, the wick 30 is supported by the protrusion 52A.

[0144] When the protrusion 52A is in contact with the second inner surface 10b in the thickness direction T, the protrusion 52A may or may not be fixed to the second inner surface 10b. For example, the protrusion 52A may or may not be bonded to the second inner surface 10b. Examples of a method for bonding the protrusion 52A and the second inner surface 10b include diffusion bonding, ultrasonic bonding, spot welding, and the like.

[0145] 3, there are a plurality of protrusions 52A, and it is preferable that all of the plurality of protrusions 52A are in contact with the second inner surface 10b in the thickness direction T. Of the plurality of protrusions 52A, some of the protrusions 52A may be in contact with the second inner surface 10b in the thickness direction T. In this manner, of the plurality of protrusions 52A, at least one protrusion 52A may be in contact with the second inner surface 10b in the thickness direction T.

[0146] When the multiple protrusions 52A are in contact with the second inner surface 10b in the thickness direction T, at least one of the multiple protrusions 52A may be fixed to the second inner surface 10b. For example, at least one of the multiple protrusions 52A may be joined to the second inner surface 10b. More specifically, all of the multiple protrusions 52A may be joined to the second inner surface 10b, or some of the protrusions 52A may be joined to the second inner surface 10b.

[0147] The protruding portion 52A does not have to be in contact with the second inner surface 10b in the thickness direction T. In other words, the protruding portion 52A may be separated in the thickness direction T from the second inner surface 10b.

[0148] Other features of the protrusion 52A are similar to those of the protrusion 51A.

[0149] When viewed from the thickness direction T, the through hole 42A may overlap the through hole 41A.

[0150] When viewed from the thickness direction T, the through hole 42A does not necessarily overlap with the through hole 41A.

[0151] Other features of the through hole 42A are similar to those of the through hole 41A.

[0152] As shown in Figures 3 and 4, in addition to the second through hole 42, the second wick layer 32 may further have a through hole 42B that does not overlap with the first through hole 41 when viewed from the thickness direction T.

[0153] 3 and 4, a protrusion may not be located on the periphery of the through hole 42B. Specifically, a protrusion approaching the first inner surface 10a or the second inner surface 10b in the thickness direction T may not be located on the periphery of the through hole 42B.

[0154] When viewed from the thickness direction T, the through hole 42B may overlap the through hole 41B.

[0155] When viewed from the thickness direction T, the through hole 42B does not necessarily overlap with the through hole 41B.

[0156] Other features of through hole 42B are similar to those of through hole 41B.

[0157] As shown in FIGS. 3 and 4, in each wick layer, flat portions exist between the through holes (including the first through holes 41, the second through holes 42, etc.).

[0158] When viewed from the thickness direction T, the second through hole 42 overlaps with the first through hole 41.

[0159] 3 and 4, when the distance in the thickness direction T between the end 52a on the first inner surface 10a side of the protrusion 52 located on the periphery of the second through hole 42 and the second inner surface 10b is A1, and the distance between the end P1 on the second inner surface 10b side of the first through hole 41 and the second inner surface 10b is B1, the relationship A1 ≧ B1 is satisfied. In the example shown in FIG. 3 and FIG. 4, the relationship A1 > B1 is satisfied.

[0160] In other words, when the height is defined based on the second inner surface 10b in the thickness direction T, as shown in Fig. 3 and Fig. 4, in the thickness direction T, the end 52a on the first inner surface 10a side of the protrusion 52 located on the periphery of the second through hole 42 is located at the same height as the end P1 on the second inner surface 10b side of the first through hole 41, or is located at a height on the first inner surface 10a side than the end P1 on the second inner surface 10b side of the first through hole 41. In the example shown in Fig. 3 and Fig. 4, in the thickness direction T, the end 52a on the first inner surface 10a side of the protrusion 52 is located at a height on the first inner surface 10a side than the end P1 on the second inner surface 10b side of the first through hole 41.

[0161] In the vapor chamber 1, the first wick layer 31 is in contact with the vapor flow path formed by the area between the first wick layer 31 and the first inner surface 10a, so that the liquid phase working medium 20 contained in the first wick layer 31, preferably the liquid phase working medium 20 contained in the area between the first wick layer 31 and the second wick layer 32, can evaporate (also called volatilization) and move to the vapor flow path while changing into a gas phase working medium 20.

[0162] On the other hand, in the vapor chamber 1, the second wick layer 32 adjacent to the first wick layer 31 on the second inner surface 10b side is further laminated on the first wick layer 31. Here, in a conventional vapor chamber in which multiple wick layers are simply laminated, the wick layer far from the vapor flow path is configured not to contact the vapor flow path at the interface with the adjacent wick layer. Therefore, in a conventional vapor chamber in which multiple wick layers are laminated, the liquid phase working medium contained in the wick layer far from the vapor flow path is unlikely to evaporate and change to a gas phase working medium. Therefore, in a conventional vapor chamber in which multiple wick layers are laminated, the driving force for driving the liquid phase working medium, which is generated by changing the liquid phase working medium to a gas phase working medium in the wick layer far from the vapor flow path, is likely to be weak, and the liquid phase working medium may be difficult to move.

[0163] In contrast, in the vapor chamber 1, the second through hole 42 provided in the second wick layer 32 far from the vapor flow path overlaps with the first through hole 41 provided in the first wick layer 31 in contact with the vapor flow path so as to satisfy the above-mentioned distance (height) relationship, so that the second through hole 42 is connected to the first through hole 41. Therefore, in the vapor chamber 1, the liquid phase working medium 20 contained in the second wick layer 32, preferably the liquid phase working medium 20 contained in the region between the second wick layer 32 and the second inner surface 10b, is easily moved to the vapor flow path while evaporating and changing into the gas phase working medium 20 through the second through hole 42 and further through the first through hole 41 connected to the second through hole 42.

[0164] As a result, in the vapor chamber 1, the driving force for driving the liquid phase working medium 20, which is generated by changing the liquid phase working medium 20 into the gas phase working medium 20, is secured not only in the first wick layer 31 but also in the second wick layer 32. Therefore, in the vapor chamber 1, even if the first wick layer 31 and the second wick layer 32 are laminated, the function of moving the liquid phase working medium 20 by capillary force is not easily impaired not only in the first wick layer 31 but also in the second wick layer 32. Therefore, in the vapor chamber 1, the cross-sectional area of ​​the region where the liquid flow path passes through the wick 30 becomes larger due to the first wick layer 31 and the second wick layer 32 being laminated, and the maximum heat transport amount is easily improved.

[0165] As described above, the vapor chamber 1 can realize a heat diffusion device capable of improving the maximum heat transport amount in a configuration in which multiple wick layers are stacked.

[0166] In the vapor chamber 1, the configuration in which the first through hole 41 and the second through hole 42 overlap to satisfy the above-mentioned distance (height) relationship is realized, for example, by adjusting the positional relationship between the first wick layer 31 and the second wick layer 32 so that the first through hole 41 and the second through hole 42 overlap with respect to the wick 30 having a configuration in which the first wick layer 31 and the second wick layer 32 are laminated in the thickness direction T, and then performing press processing simultaneously from both the first wick layer 31 side and the second wick layer 32 side. The method of realizing the configuration in which the first through hole 41 and the second through hole 42 overlap to satisfy the above-mentioned distance (height) relationship is not limited to the method of performing press processing described above.

[0167] 3 and 4, when the first wick layer 31 is provided with a through hole 41A or a through hole 41B that does not overlap with the second through hole 42 when viewed from the thickness direction T, in addition to the first through hole 41, when the distance between the end Q1 on the first inner surface 10a side of the through hole 41A or the through hole 41B other than the first through hole 41 of the first wick layer 31 and the second inner surface 10b in the thickness direction T is C1, it is preferable that the relationship A1 ≧ C1 is satisfied. In the example shown in FIG. 3 and FIG. 4, the relationship A1 > C1 is satisfied.

[0168] In other words, as shown in Figures 3 and 4, when the first wick layer 31 is further provided with a through hole 41A or a through hole 41B that does not overlap with the second through hole 42 when viewed from the thickness direction T in addition to the first through hole 41, it is preferable that the end 52a on the first inner surface 10a side of the protrusion 52 located on the periphery of the second through hole 42 in the thickness direction T is located at the same height as the end Q1 on the first inner surface 10a side of the through hole 41A or the through hole 41B of the first wick layer 31, or is located at a height on the first inner surface 10a side higher than the end Q1 on the first inner surface 10a side of the through hole 41A or the through hole 41B of the first wick layer 31. In the example shown in Figures 3 and 4, the end 52a on the first inner surface 10a side of the protrusion 52 is located at a height on the first inner surface 10a side higher than the end Q1 on the first inner surface 10a side of the through hole 41A or the through hole 41B in the thickness direction T.

[0169] In the vapor chamber 1, the second through hole 42 overlaps with the first through hole 41 so as to satisfy the above-mentioned distance (height) relationship, so that the liquid phase working medium 20 contained in the second wick layer 32, preferably the liquid phase working medium 20 contained in the region between the second wick layer 32 and the second inner surface 10b, is more likely to move to the vapor flow path while evaporating and changing into the gas phase working medium 20 through the second through hole 42 and further through the first through hole 41. Therefore, in the vapor chamber 1, the function of moving the liquid phase working medium 20 by capillary force is more unlikely to be impaired by the second wick layer 32, and as a result, the maximum heat transport amount is more likely to be improved.

[0170] 3 and 4, the distance between the end of through hole 41A on the first inner surface 10a side and the second inner surface 10b, and the distance between the end of through hole 41B on the first inner surface 10a side and the second inner surface 10b are the same as each other, which is distance C1. In other words, in the example shown in Fig. 3 and 4, the ends of through holes 41A and 41B on the first inner surface 10a side are located at the same height as each other, which is end Q1.

[0171] The distance between the end of the through hole 41A on the first inner surface 10a side and the second inner surface 10b, and the distance between the end of the through hole 41B on the first inner surface 10a side and the second inner surface 10b may be different from each other. In other words, the end of the through hole 41A on the first inner surface 10a side and the end of the through hole 41B on the first inner surface 10a side may be located at different heights from each other. In this case, the end of the through hole 41A on the first inner surface 10a side may be located at a height higher on the first inner surface 10a side than the end of the through hole 41B on the first inner surface 10a side, or may be located at a height higher on the second inner surface 10b side than the end of the through hole 41B on the first inner surface 10a side.

[0172] When the ends of the through hole 41A and the through hole 41B on the first inner surface 10a side are located at different heights, in the thickness direction T, the end 52a of the protrusion 52 on the first inner surface 10a side may be located at the same height as the end of the through hole 41A on the first inner surface 10a side, or may be located at a height on the first inner surface 10a side than the end of the through hole 41A on the first inner surface 10a side. Alternatively, in the thickness direction T, the end 52a of the protrusion 52 on the first inner surface 10a side may be located at the same height as the end of the through hole 41B on the first inner surface 10a side, or may be located at a height on the first inner surface 10a side than the end of the through hole 41B on the first inner surface 10a side.

[0173] 3 and 4, it is preferable that at least a part of the inner surface of the protruding portion 51 located on the periphery of the first through hole 41 contacts at least a part of the outer surface of the protruding portion 52 located on the periphery of the second through hole 42. In the example shown in FIG. 3 and FIG. 4, a part of the inner surface of the protruding portion 51 contacts a part of the outer surface of the protruding portion 52.

[0174] When at least a portion of the inner surface of the protrusion 51 is in contact with at least a portion of the outer surface of the protrusion 52, the first wick layer 31 and the second wick layer 32 are joined to each other, for example, by crimping the protrusions 51 and the protrusions 52. This makes it difficult for the positional relationship between the first wick layer 31 and the second wick layer 32 to shift.

[0175] The inner surface of the protruding portion 51 does not have to be in contact with the outer surface of the protruding portion 52 .

[0176] The vapor chamber 1 operates, for example, as follows.

[0177] In the vapor chamber 1, the liquid phase working medium 20 evaporates by absorbing heat from the heat source HS in the wick 30 and the liquid flow path present in the region near the evaporation part EP, and changes into the gas phase working medium 20. Then, the gas phase working medium 20 generated in the evaporation part EP moves through the vapor flow path to a region away from the evaporation part EP, for example, around the end opposite the evaporation part EP in the length direction L of the vapor flow path, and is cooled there and changes into the liquid phase working medium 20. Hereinafter, the part where the gas phase working medium 20 condenses and changes into the liquid phase working medium 20 is referred to as the condensation part. The condensation part is likely to be located in a region away from the evaporation part EP, for example, around the end opposite the evaporation part EP in the length direction L of the internal space of the housing 10. Then, the liquid phase working medium 20 generated in the condensation part is transported to the evaporation part EP after being collected in the wick 30 and the liquid flow path.

[0178] In the vapor chamber 1, the above process is repeated, and the working medium 20 circulates while undergoing a phase change between gas and liquid. At this time, heat from the heat source HS is absorbed as latent heat of evaporation that changes the liquid-phase working medium 20 to the gas-phase working medium 20 in the evaporation section EP, and then released as latent heat of condensation that changes the gas-phase working medium 20 to the liquid-phase working medium 20 in the condensation section (for example, a region separated from the evaporation section EP in the length direction L). In this way, the vapor chamber 1 operates autonomously without requiring an external power source, and furthermore, by utilizing the latent heat of evaporation and latent heat of condensation of the working medium 20, the heat from the heat source HS can be diffused two-dimensionally at high speed.

[0179] <Embodiment 2> In the heat spreading device of embodiment 2 of the present invention, the wick further includes a third wick layer adjacent to the second inner surface side of the second wick layer in the thickness direction.

[0180] In the heat diffusion device of embodiment 2 of the present invention, the first wick layer is located closest to the first inner surface in the thickness direction of the wick, and the third wick layer is located closest to the second inner surface in the thickness direction of the wick.

[0181] Except for the above points, the heat spreading device of the second embodiment of the present invention is similar to the heat spreading device of the first embodiment of the present invention.

[0182] Fig. 5 is a schematic cross-sectional view showing an example of a cross section of a heat spreading device according to embodiment 2 of the present invention, Fig. 6 is a schematic cross-sectional view showing an enlarged portion of the heat spreading device shown in Fig. 5.

[0183] FIG. 5 shows a cross section taken at a position corresponding to FIG.

[0184] In the vapor chamber 2 shown in FIG. 5, the wick 30 further includes a third wick layer 33 adjacent to the second wick layer 32 on the second inner surface 10b side in the thickness direction T.

[0185] 5, the first wick layer 31 is located closest to the first inner surface 10a in the thickness direction T of the wick 30. Furthermore, as shown in Fig. 5, the third wick layer 33 is located closest to the second inner surface 10b in the thickness direction T of the wick 30. That is, in the vapor chamber 2, the wick 30 has a configuration in which three wick layers, the first wick layer 31, the second wick layer 32, and the third wick layer 33, are stacked in the thickness direction T.

[0186] As shown in FIGS. 5 and 6, the third wick layer 33 is preferably provided with third through holes 43 in the thickness direction T.

[0187] The third through hole 43 exerts a capillary force on the working medium 20. That is, the working medium 20 moves inside the third through hole 43 due to the capillary force.

[0188] Other features of the third through hole 43 are similar to those of the first through hole 41 and the second through hole 42.

[0189] As shown in FIGS. 5 and 6, it is preferable that a protrusion 53 approaching the first inner surface 10a in the thickness direction T is located on the periphery of the third through hole 43.

[0190] The protrusion 53 is preferably located around the entire periphery of the third through-hole 43 .

[0191] The protrusion 53 may be located on a part of the periphery of the third through-hole 43 .

[0192] In the case where a plurality of protruding portions 53 are present due to the provision of a plurality of third through holes 43, it is preferable that all of the plurality of protruding portions 53 are located on the entire periphery of the third through hole 43. Of the plurality of protruding portions 53, some of the protruding portions 53 may be located on the entire periphery of the third through hole 43. In this manner, of the plurality of protruding portions 53, at least some of the protruding portions 53 may be located on the entire periphery of the third through hole 43.

[0193] 5, it is preferable that the protruding portion 53 is not in contact with the first inner surface 10a in the thickness direction T. In other words, it is preferable that the protruding portion 53 is separated from the first inner surface 10a in the thickness direction T.

[0194] The protruding portion 53 may be in contact with the first inner surface 10a in the thickness direction T.

[0195] When a plurality of protrusions 53 are present, it is preferable that all of the plurality of protrusions 53 are separated from the first inner surface 10a in the thickness direction T. Of the plurality of protrusions 53, some of the protrusions 53 may be separated from the first inner surface 10a in the thickness direction T. In this manner, of the plurality of protrusions 53, at least one protrusion 53 may be separated from the first inner surface 10a in the thickness direction T.

[0196] The cross-sectional shape of the protrusions 53 when viewed in a cross section along the thickness direction T is not particularly limited, and may be a shape in which the distance between the inner surfaces of the protrusions 53 (the distance in the width direction W in Figs. 5 and 6) decreases toward the first inner surface 10a as shown in Figs. 5 and 6, or may be a shape in which the distance between the inner surfaces of the protrusions 53 increases. Furthermore, the cross-sectional shape of the protrusions 53 may be a shape in which the distance between the inner surfaces of the protrusions 53 is constant toward the first inner surface 10a.

[0197] The protruding portion 53 may be bent at the end on the first inner surface 10a side toward the third through hole 43 (inward), or may be bent toward the opposite side to the third through hole 43 (outward).

[0198] When multiple protrusions 53 are present, when viewed in a cross section along the thickness direction T, the cross-sectional shapes of the multiple protrusions 53 may be the same as each other, may be different from each other, or may be partially different.

[0199] There is no particular limitation on the size of the protruding portion 53. For example, the dimension of the protruding portion 53 in the thickness direction T may be larger than the dimension of the third through hole 43 in the planar direction (for example, the length direction L or the width direction W), may be smaller than the dimension of the third through hole 43 in the planar direction, or may be the same as the dimension of the third through hole 43 in the planar direction.

[0200] When there are multiple protrusions 53, the sizes of the multiple protrusions 53 may be the same as each other, may be different from each other, or may be partially different. For example, the dimensions of the multiple protrusions 53 in the thickness direction T may be the same as each other, may be different from each other, or may be partially different.

[0201] The dimensions, shape, arrangement, etc. of the protrusion 53 in an actual product may differ from the example shown in FIG.

[0202] As shown in FIGS. 5 and 6, in addition to the third through-holes 43, the third wick layer 33 may further be provided with through-holes 43A in the thickness direction T.

[0203] As shown in FIGS. 5 and 6, a protruding portion 53A approaching the second inner surface 10b in the thickness direction T may be located on the periphery of the through hole 43A.

[0204] 5, the protruding portion 53A is preferably in contact with the second inner surface 10b in the thickness direction T. In this case, the wick 30 is supported by the protruding portion 53A.

[0205] The protruding portion 53A does not have to be in contact with the second inner surface 10b in the thickness direction T. In other words, the protruding portion 53A may be separated in the thickness direction T from the second inner surface 10b.

[0206] Other features of the protrusion 53A are similar to those of the protrusion 51A and the protrusion 52A.

[0207] When viewed from the thickness direction T, the through hole 43A may overlap the first through hole 41, may overlap the second through hole 42, may overlap the through hole 41A, or may overlap the through hole 42A.

[0208] When viewed from the thickness direction T, the through hole 43A does not necessarily overlap with the first through hole 41, the second through hole 42, the through hole 41A, and the through hole 42A.

[0209] Other features of the through hole 43A are similar to those of the through holes 41A and 42A.

[0210] As shown in FIGS. 5 and 6, in addition to the third through-holes 43, the third wick layer 33 may further be provided with through-holes 43B in the thickness direction T.

[0211] 5 and 6, a protrusion may not be located on the periphery of the through hole 43B. Specifically, a protrusion approaching the first inner surface 10a or the second inner surface 10b in the thickness direction T may not be located on the periphery of the through hole 43B.

[0212] When viewed from the thickness direction T, the through hole 43B may overlap the through hole 41B or may overlap the through hole 42B.

[0213] When viewed from the thickness direction T, the through hole 43B does not necessarily overlap with the through hole 41B and the through hole 42B.

[0214] Other features of the through hole 43B are similar to those of the through holes 41B and 42B.

[0215] When viewed from the thickness direction T, the third through hole 43 preferably overlaps the second through hole 42 .

[0216] 5 and 6, when the distance in the thickness direction T between the end 53a on the first inner surface 10a side of the protrusion 53 located on the periphery of the third through hole 43 and the second inner surface 10b is A2, and the distance between the end P2 on the second inner surface 10b side of the second through hole 42 and the second inner surface 10b is B2, it is preferable that the relationship A2 ≧ B2 is satisfied. In the example shown in Fig. 5 and Fig. 6, the relationship A2 > B2 is satisfied.

[0217] In other words, as shown in Figures 5 and 6, in the thickness direction T, it is preferable that the end 53a on the first inner surface 10a side of the protrusion 53 located on the periphery of the third through hole 43 is located at the same height as the end P2 on the second inner surface 10b side of the second through hole 42, or is located at a height on the first inner surface 10a side higher than the end P2 on the second inner surface 10b side of the second through hole 42. In the example shown in Figures 5 and 6, in the thickness direction T, the end 53a on the first inner surface 10a side of the protrusion 53 is located at a height on the first inner surface 10a side higher than the end P2 on the second inner surface 10b side of the second through hole 42.

[0218] In the vapor chamber 2, the third through hole 43 provided in the third wick layer 33 overlaps with the second through hole 42 provided in the second wick layer 32, which is closer to the vapor flow path than the third wick layer 33, so as to satisfy the above-mentioned distance (height) relationship, and thus the third through hole 43 is connected to the second through hole 42. Furthermore, in the vapor chamber 2, similar to the vapor chamber 1, the second through hole 42 provided in the second wick layer 32 overlaps with the first through hole 41 provided in the first wick layer 31 that contacts the vapor flow path, and thus the second through hole 42 is connected to the first through hole 41. That is, in the vapor chamber 2, the third through hole 43 is connected to the first through hole 41 through the second through hole 42. Therefore, in the vapor chamber 2, the liquid phase working medium 20 contained in the third wick layer 33, preferably the liquid phase working medium 20 contained in the region between the third wick layer 33 and the second inner surface 10b, is likely to evaporate and change into gas phase working medium 20 through the third through hole 43, the second through hole 42 connected to the third through hole 43, and further through the first through hole 41 connected to the second through hole 42, and move to the vapor flow path.

[0219] As a result, in the vapor chamber 2, the driving force for driving the liquid phase working medium 20, which is generated by changing the liquid phase working medium 20 into the gas phase working medium 20, is secured not only in the first wick layer 31 and the second wick layer 32 but also in the third wick layer 33. Therefore, even if the first wick layer 31, the second wick layer 32, and the third wick layer 33 are laminated in the vapor chamber 2, the function of moving the liquid phase working medium 20 by capillary force is not easily impaired not only in the first wick layer 31 and the second wick layer 32 but also in the third wick layer 33. Therefore, in the vapor chamber 2, the cross-sectional area of ​​the region where the liquid flow path passes through the wick 30 is increased by laminating the first wick layer 31, the second wick layer 32, and the third wick layer 33, and therefore the maximum heat transport amount is easily improved.

[0220] As shown in Figures 5 and 6, in addition to the second through hole 42, the second wick layer 32 may further have a through hole 42A that does not overlap with the third through hole 43 when viewed from the thickness direction T.

[0221] As shown in FIGS. 5 and 6, a protruding portion 52A approaching the second inner surface 10b in the thickness direction T may be located on the periphery of the through hole 42A.

[0222] Other features of the through hole 42A and the protrusion 52A shown in FIGS. 5 and 6 are similar to those of the through hole 42A and the protrusion 52A shown in FIGS. 3 and 4, respectively.

[0223] As shown in Figures 5 and 6, in addition to the second through hole 42, the second wick layer 32 may further have a through hole 42B that does not overlap with the third through hole 43 when viewed from the thickness direction T.

[0224] 5 and 6, a protrusion may not be located on the periphery of the through hole 42B. Specifically, a protrusion approaching the first inner surface 10a or the second inner surface 10b in the thickness direction T may not be located on the periphery of the through hole 42B.

[0225] Other features of the through-hole 42B shown in FIGS. 5 and 6 are similar to those of the through-hole 42B shown in FIGS.

[0226] 5 and 6, when the second wick layer 32 is provided with a through hole 42A or a through hole 42B that does not overlap with the third through hole 43 when viewed from the thickness direction T, in addition to the second through hole 42, when the distance between the end Q2 on the first inner surface 10a side of the through hole 42A or the through hole 42B other than the second through hole 42 of the second wick layer 32 and the second inner surface 10b in the thickness direction T is C2, it is preferable that the relationship A2 ≧ C2 is satisfied. In the example shown in FIG. 5 and FIG. 6, the relationship A2 > C2 is satisfied.

[0227] In other words, as shown in Figures 5 and 6, when the second wick layer 32 is further provided with a through hole 42A or a through hole 42B that does not overlap with the third through hole 43 when viewed from the thickness direction T in addition to the second through hole 42, it is preferable that the end 53a on the first inner surface 10a side of the protrusion 53 located on the periphery of the third through hole 43 in the thickness direction T is located at the same height as the end Q2 on the first inner surface 10a side of the through hole 42A or the through hole 42B of the second wick layer 32, or is located at a height on the first inner surface 10a side higher than the end Q2 on the first inner surface 10a side of the through hole 42A or the through hole 42B of the second wick layer 32. In the example shown in Figures 5 and 6, the end 53a on the first inner surface 10a side of the protrusion 53 is located at a height on the first inner surface 10a side higher than the end Q2 on the first inner surface 10a side of the through hole 42A or the through hole 42B in the thickness direction T.

[0228] In the vapor chamber 2, the third through hole 43 overlaps with the second through hole 42 so as to satisfy the above-mentioned distance (height) relationship, so that the liquid phase working medium 20 contained in the third wick layer 33, preferably the liquid phase working medium 20 contained in the region between the third wick layer 33 and the second inner surface 10b, is more likely to move to the vapor flow path while evaporating and changing into the gas phase working medium 20 through the third through hole 43, the second through hole 42, and further the first through hole 41. Therefore, in the vapor chamber 2, the function of moving the liquid phase working medium 20 by capillary force is more unlikely to be impaired by the third wick layer 33, and as a result, the maximum heat transport amount is more likely to be improved.

[0229] 5 and 6, the distance between the end of through hole 42A on the first inner surface 10a side and the second inner surface 10b, and the distance between the end of through hole 42B on the first inner surface 10a side and the second inner surface 10b are the same as each other, which is distance C2. In other words, in the example shown in Fig. 5 and 6, the ends of through holes 42A and 42B on the first inner surface 10a side are located at the same height as each other, which is end Q2.

[0230] The distance between the end of the through hole 42A on the first inner surface 10a side and the second inner surface 10b, and the distance between the end of the through hole 42B on the first inner surface 10a side and the second inner surface 10b may be different from each other. In other words, the end of the through hole 42A on the first inner surface 10a side and the end of the through hole 42B on the first inner surface 10a side may be located at different heights from each other. In this case, the end of the through hole 42A on the first inner surface 10a side may be located at a height on the first inner surface 10a side of the through hole 42B, or may be located at a height on the second inner surface 10b side of the end of the through hole 42B on the first inner surface 10a side.

[0231] When the ends of the through hole 42A and the through hole 42B on the first inner surface 10a side are located at different heights, in the thickness direction T, the end 53a of the protrusion 53 on the first inner surface 10a side may be located at the same height as the end of the through hole 42A on the first inner surface 10a side, or may be located at a height on the first inner surface 10a side higher than the end of the through hole 42A on the first inner surface 10a side. Alternatively, in the thickness direction T, the end 53a of the protrusion 53 on the first inner surface 10a side may be located at the same height as the end of the through hole 42B on the first inner surface 10a side, or may be located at a height on the first inner surface 10a side higher than the end of the through hole 42B on the first inner surface 10a side.

[0232] As shown in Figures 5 and 6, it is preferable that the relationship A2 ≧ B1 is satisfied. In the example shown in Figures 5 and 6, the relationship A2 > B1 is satisfied.

[0233] In other words, as shown in Figures 5 and 6, in the thickness direction T, it is preferable that the end 53a on the first inner surface 10a side of the protrusion 53 located on the periphery of the third through hole 43 is located at the same height as the end P1 on the second inner surface 10b side of the first through hole 41, or is located at a height on the first inner surface 10a side higher than the end P1 on the second inner surface 10b side of the first through hole 41. In the example shown in Figures 5 and 6, in the thickness direction T, the end 53a on the first inner surface 10a side of the protrusion 53 is located at a height on the first inner surface 10a side higher than the end P1 on the second inner surface 10b side of the first through hole 41.

[0234] In the vapor chamber 2, the third through hole 43 overlaps with the second through hole 42 and further with the first through hole 41 so as to satisfy the above-mentioned relationship of distance (height), so that the liquid phase working medium 20 contained in the third wick layer 33, preferably the liquid phase working medium 20 contained in the region between the third wick layer 33 and the second inner surface 10b, is more likely to move to the vapor flow path while evaporating and changing into the gas phase working medium 20 through the third through hole 43, the second through hole 42, and further through the first through hole 41. As a result, in the vapor chamber 2, the maximum heat transport amount is more likely to be improved.

[0235] 5 and 6, when the first wick layer 31 is provided with a through hole 41A or a through hole 41B that does not overlap with the second through hole 42 when viewed from the thickness direction T, in addition to the first through hole 41, when the distance between the end Q1 on the first inner surface 10a side of the through hole 41A or the through hole 41B other than the first through hole 41 of the first wick layer 31 and the second inner surface 10b in the thickness direction T is C1, it is preferable that the relationship A2≧C1 is satisfied. In the example shown in FIG. 5 and FIG. 6, the relationship A2>C1 is satisfied.

[0236] In other words, as shown in Fig. 5 and Fig. 6, when the first wick layer 31 is further provided with a through hole 41A or a through hole 41B that does not overlap with the second through hole 42 when viewed from the thickness direction T in addition to the first through hole 41, it is preferable that the end 53a on the first inner surface 10a side of the protrusion 53 located on the periphery of the third through hole 43 in the thickness direction T is located at the same height as the end Q1 on the first inner surface 10a side of the through hole 41A or the through hole 41B of the first wick layer 31, or is located at a height on the first inner surface 10a side higher than the end Q1 on the first inner surface 10a side of the through hole 41A or the through hole 41B of the first wick layer 31. In the example shown in Fig. 5 and Fig. 6, the end 53a on the first inner surface 10a side of the protrusion 53 is located at a height on the first inner surface 10a side higher than the end Q1 on the first inner surface 10a side of the through hole 41A or the through hole 41B in the thickness direction T.

[0237] In the vapor chamber 2, the third through hole 43 overlaps with the second through hole 42 and further with the first through hole 41 so as to satisfy the above-mentioned relationship of distance (height), so that the liquid phase working medium 20 contained in the third wick layer 33, preferably the liquid phase working medium 20 contained in the region between the third wick layer 33 and the second inner surface 10b, is more likely to move to the vapor flow path while evaporating and changing into the gas phase working medium 20 through the third through hole 43, the second through hole 42, and further through the first through hole 41. As a result, in the vapor chamber 2, the maximum heat transport amount is more likely to be improved.

[0238] 5 and 6, it is preferable that at least a part of the inner surface of protrusion 52 located on the periphery of second through hole 42 contacts at least a part of the outer surface of protrusion 53 located on the periphery of third through hole 43. In the example shown in Figs. 5 and 6, a part of the inner surface of protrusion 52 contacts a part of the outer surface of protrusion 53.

[0239] When at least a portion of the inner surface of the protrusion 52 is in contact with at least a portion of the outer surface of the protrusion 53, the second wick layer 32 and the third wick layer 33 are joined to each other, for example, by crimping the protrusions 52 and the protrusions 53. This makes it difficult for the second wick layer 32 and the third wick layer 33 to shift in position relative to each other.

[0240] The inner surface of protrusion 52 does not have to be in contact with the outer surface of protrusion 53 .

[0241] <Embodiment 3> In the heat diffusion devices of the first and second embodiments of the present invention, a configuration is shown in which flat portions exist between the through holes (including the first through hole, the second through hole, the third through hole, etc.) in the wick, but flat portions do not have to exist between the through holes, and for example, curved portions may exist between the through holes.

[0242] In the heat diffusion device of embodiment 3 of the present invention, similar to the heat diffusion device of embodiment 1 of the present invention, the wick has a configuration in which two wick layers, a first wick layer and a second wick layer, are stacked in the thickness direction.

[0243] The heat spreading device of the third embodiment of the present invention is different from the heat spreading device of the first embodiment of the present invention in that curved portions exist between the through holes.

[0244] Fig. 7 is a schematic plan view showing an example of the internal structure of the heat spreading device according to the third embodiment of the present invention. Fig. 8 is a schematic cross-sectional view showing an example of a cross section along the line segment b1-b2 of the heat spreading device shown in Fig. 7. Fig. 9 is a schematic cross-sectional view showing an enlarged part of the heat spreading device shown in Fig. 8. Fig. 10 is a schematic cross-sectional view showing an example of a cross section along the line segment b3-b4 of the heat spreading device shown in Fig. 7.

[0245] In the vapor chamber 3 shown in FIGS. 7, 8, and 10, the wick 30 has a configuration in which two wick layers, a first wick layer 31 and a second wick layer 32, are laminated in the thickness direction T.

[0246] As shown in FIGS. 8 and 9, the first wick layer 31 is provided with first through holes 41 in the thickness direction T.

[0247] As shown in FIGS. 8 and 9, it is preferable that a protrusion 51 approaching the first inner surface 10a in the thickness direction T is located on the periphery of the first through hole 41.

[0248] Other features of the first through hole 41 and the protrusion 51 shown in FIGS. 8 and 9 are similar to those of the first through hole 41 and the protrusion 51 shown in FIGS. 3 and 4, respectively.

[0249] As shown in Figures 8 and 9, in addition to the first through hole 41, the first wick layer 31 may further have a through hole 41C that does not overlap with the second through hole 42 described later when viewed from the thickness direction T.

[0250] As shown in FIGS. 8 and 9, a protruding portion 51C approaching the first inner surface 10a in the thickness direction T may be located on the periphery of the through hole 41C.

[0251] The protrusion 51C is preferably located around the entire periphery of the through-hole 41C.

[0252] The protrusion 51C may be located on a portion of the periphery of the through-hole 41C.

[0253] In the example shown in Fig. 8, a plurality of protruding portions 51C are provided due to the provision of a plurality of through holes 41C, but it is preferable that all of the plurality of protruding portions 51C are located on the entire periphery of the through hole 41C. Of the plurality of protruding portions 51C, some of the protruding portions 51C may be located on the entire periphery of the through hole 41C. In this manner, of the plurality of protruding portions 51C, at least some of the protruding portions 51C may be located on the entire periphery of the through hole 41C.

[0254] The cross-sectional shape of the protrusions 51C when viewed along a cross section in the thickness direction T is not particularly limited, and may be a shape in which the distance between the inner surfaces of the protrusions 51C (the distance in the width direction W in Figs. 8 and 9) decreases toward the first inner surface 10a as shown in Figs. 8 and 9, or may be a shape in which the distance between the inner surfaces of the protrusions 51C increases. Furthermore, the cross-sectional shape of the protrusions 51C may be a shape in which the distance between the inner surfaces of the protrusions 51C is constant toward the first inner surface 10a.

[0255] The protruding portion 51C may be bent at an end portion on the first inner surface 10a side toward the through hole 41C (inward), or may be bent toward the opposite side to the through hole 41C (outward).

[0256] In the example shown in Figure 8, there are multiple protrusions 51C, and when viewed in a cross section along the thickness direction T, the cross-sectional shapes of the multiple protrusions 51C may be the same as each other, may be different from each other, or may be partially different.

[0257] The size of the protrusion 51C is not particularly limited. For example, the dimension of the protrusion 51C in the thickness direction T may be larger than the dimension of the through hole 41C in the surface direction (for example, the length direction L or the width direction W), may be smaller than the dimension of the through hole 41C in the surface direction, or may be the same as the dimension of the through hole 41C in the surface direction.

[0258] 8, there are multiple protrusions 51C, but the sizes of the multiple protrusions 51C may be the same as each other, may be different from each other, or may be partially different. For example, the dimensions of the multiple protrusions 51C in the thickness direction T may be the same as each other, may be different from each other, or may be partially different.

[0259] The dimensions, shape, arrangement, etc. of the protrusion 51C may differ from the example shown in FIG. 8 in an actual product.

[0260] As shown in Figure 10, in addition to the first through hole 41, the first wick layer 31 may further have a through hole 41D that does not overlap with the second through hole 42 described later when viewed from the thickness direction T.

[0261] As shown in FIG. 10, a protruding portion 51D approaching the second inner surface 10b in the thickness direction T may be located on the periphery of the through hole 41D.

[0262] The protrusion 51D is preferably located around the entire periphery of the through-hole 41D.

[0263] The protrusion 51D may be located on a part of the periphery of the through hole 41D.

[0264] In the example shown in Fig. 10, a plurality of protrusions 51D are provided due to the provision of a plurality of through holes 41D, but it is preferable that all of the plurality of protrusions 51D are located on the entire periphery of the through hole 41D. Of the plurality of protrusions 51D, some of the protrusions 51D may be located on the entire periphery of the through hole 41D. In this way, of the plurality of protrusions 51D, at least some of the protrusions 51D may be located on the entire periphery of the through hole 41D.

[0265] The cross-sectional shape of the protrusions 51D when viewed along a cross section in the thickness direction T is not particularly limited, and may be a shape in which the distance between the inner surfaces of the protrusions 51D (the distance in the width direction W in FIG. 10) decreases toward the second inner surface 10b as shown in Fig. 10, or may be a shape in which the distance between the inner surfaces of the protrusions 51D increases. Also, the cross-sectional shape of the protrusions 51D may be a shape in which the distance between the inner surfaces of the protrusions 51D is constant toward the second inner surface 10b.

[0266] The protruding portion 51D may be bent at the end on the second inner surface 10b side toward the through hole 41D (inward) or toward the opposite side to the through hole 41D (outward).

[0267] In the example shown in Figure 10, there are multiple protrusions 51D, and when viewed in a cross section along the thickness direction T, the cross-sectional shapes of the multiple protrusions 51D may be the same as each other, may be different from each other, or may be partially different.

[0268] The size of the protrusion 51D is not particularly limited. For example, the dimension of the protrusion 51D in the thickness direction T may be larger than the dimension of the through hole 41D in the surface direction (for example, the length direction L or the width direction W), may be smaller than the dimension of the through hole 41D in the surface direction, or may be the same as the dimension of the through hole 41D in the surface direction.

[0269] 10, there are multiple protrusions 51D, but the sizes of the multiple protrusions 51D may be the same as each other, may be different from each other, or may be partially different. For example, the dimensions of the multiple protrusions 51D in the thickness direction T may be the same as each other, may be different from each other, or may be partially different.

[0270] The dimensions, shape, arrangement, etc. of the protrusion 51D may differ from the example shown in FIG. 10 in an actual product.

[0271] As shown in FIGS. 8 and 9, the second wick layer 32 is provided with second through holes 42 in the thickness direction T.

[0272] As shown in FIGS. 8 and 9, a protrusion 52 is located on the periphery of the second through hole 42 and approaches the first inner surface 10a in the thickness direction T.

[0273] Other features of the second through hole 42 and the protrusion 52 shown in FIGS. 8 and 9 are similar to those of the second through hole 42 and the protrusion 52 shown in FIGS.

[0274] As shown in Figures 8 and 9, in addition to the second through hole 42, the second wick layer 32 may further have a through hole 42C that does not overlap with the first through hole 41 when viewed from the thickness direction T.

[0275] As shown in FIGS. 8 and 9, a protruding portion 52C approaching the first inner surface 10a in the thickness direction T may be located on the periphery of the through hole 42C.

[0276] Other features of the protrusion 52C are similar to those of the protrusion 51C.

[0277] When viewed from the thickness direction T, the through hole 42C may overlap with the through hole 41C.

[0278] When viewed from the thickness direction T, the through hole 42C does not necessarily overlap with the through hole 41C.

[0279] Other features of through hole 42C are similar to those of through hole 41C.

[0280] As shown in FIG. 10, in addition to the second through holes 42, the second wick layer 32 may further be provided with through holes 42D that do not overlap with the first through holes 41 when viewed in the thickness direction T.

[0281] As shown in FIG. 10, a protruding portion 52D approaching the second inner surface 10b in the thickness direction T may be located on the periphery of the through hole 42D.

[0282] 10, the protrusion 52D is preferably in contact with the second inner surface 10b in the thickness direction T. In this case, the wick 30 is supported by the protrusion 52D.

[0283] The protruding portion 52D does not have to be in contact with the second inner surface 10b in the thickness direction T. In other words, the protruding portion 52D may be separated in the thickness direction T from the second inner surface 10b.

[0284] Other features of the protrusion 52D are similar to those of the protrusion 51D.

[0285] When viewed from the thickness direction T, the through hole 42D may overlap the through hole 41D.

[0286] When viewed from the thickness direction T, the through hole 42D does not necessarily overlap with the through hole 41D.

[0287] Other features of through hole 42D are similar to those of through hole 41D.

[0288] As shown in FIGS. 8, 9, and 10, in each wick layer, curved portions exist between the through holes (including the first through holes 41, the second through holes 42, etc.).

[0289] 8 and 9, when the distance between the end R1 of the first through hole 41 on the first inner surface 10a side and the second inner surface 10b in the thickness direction T is D1, it is preferable that the relationship A1≧D1 is satisfied. In the example shown in Fig. 8 and 9, the relationship A1>D1 is satisfied.

[0290] In other words, as shown in Figures 8 and 9, in the thickness direction T, it is preferable that the end 52a on the first inner surface 10a side of the protrusion 52 located on the periphery of the second through hole 42 is located at the same height as the end R1 on the first inner surface 10a side of the first through hole 41, or is located at a height on the first inner surface 10a side higher than the end R1 on the first inner surface 10a side of the first through hole 41. In the example shown in Figures 8 and 9, in the thickness direction T, the end 52a on the first inner surface 10a side of the protrusion 52 is located at a height on the first inner surface 10a side higher than the end R1 on the first inner surface 10a side of the first through hole 41.

[0291] In the vapor chamber 3, the second through hole 42 overlaps with the first through hole 41 so as to satisfy the above-mentioned distance (height) relationship, so that the liquid phase working medium 20 contained in the second wick layer 32, preferably the liquid phase working medium 20 contained in the region between the second wick layer 32 and the second inner surface 10b, can easily move to the vapor flow path while evaporating and changing into the gas phase working medium 20 through the second through hole 42 and further through the first through hole 41. As a result, the maximum heat transport amount in the vapor chamber 3 can be easily improved.

[0292] <Embodiment 4> In the heat diffusion device of embodiment 4 of the present invention, similar to the heat diffusion device of embodiment 2 of the present invention, the wick has a configuration in which three wick layers, namely a first wick layer, a second wick layer, and a third wick layer, are stacked in the thickness direction.

[0293] The heat spreading device of the fourth embodiment of the present invention is different from the heat spreading device of the second embodiment of the present invention in that curved portions exist between the through holes.

[0294] Fig. 11 is a schematic cross-sectional view showing an example of a cross section of the heat spreading device according to the fourth embodiment of the present invention. Fig. 12 is a schematic cross-sectional view showing an enlarged part of the heat spreading device shown in Fig. 11. Fig. 13 is a schematic cross-sectional view showing another example of a cross section of the heat spreading device according to the fourth embodiment of the present invention.

[0295] 11 and 13 show cross sections at positions corresponding to those of FIGS. 8 and 10, respectively.

[0296] In the vapor chamber 4 shown in Figures 11 and 13, the wick 30 has a configuration in which three wick layers, a first wick layer 31, a second wick layer 32, and a third wick layer 33, are stacked in the thickness direction T.

[0297] As shown in FIGS. 11 and 12, the third wick layer 33 is preferably provided with third through holes 43 in the thickness direction T.

[0298] As shown in FIGS. 11 and 12, it is preferable that a protrusion 53 approaching the first inner surface 10a in the thickness direction T is located on the periphery of the third through hole 43.

[0299] Other features of the third through hole 43 and the protrusion 53 shown in FIGS. 11 and 12 are similar to those of the third through hole 43 and the protrusion 53 shown in FIGS. 5 and 6, respectively.

[0300] As shown in FIGS. 11 and 12, in addition to the third through-holes 43, the third wick layer 33 may further be provided with through-holes 43C in the thickness direction T.

[0301] As shown in FIGS. 11 and 12, a protruding portion 53C approaching the first inner surface 10a in the thickness direction T may be located on the periphery of the through hole 43C.

[0302] Other features of the protrusion 53C are similar to those of the protrusion 51C and the protrusion 52C.

[0303] When viewed from the thickness direction T, the through hole 43C may overlap the through hole 41C or the through hole 42C.

[0304] When viewed from the thickness direction T, the through hole 43C does not necessarily overlap with the through hole 41C and the through hole 42C.

[0305] Other features of the through hole 43C are similar to those of the through holes 41C and 42C.

[0306] As shown in FIG. 13, in addition to the third through-holes 43, the third wick layer 33 may further be provided with through-holes 43D in the thickness direction T.

[0307] As shown in FIG. 13, a protruding portion 53D approaching the second inner surface 10b in the thickness direction T may be located on the periphery of the through hole 43D.

[0308] 13, the protrusion 53D is preferably in contact with the second inner surface 10b in the thickness direction T. In this case, the wick 30 is supported by the protrusion 53D.

[0309] The protruding portion 53D does not have to be in contact with the second inner surface 10b in the thickness direction T. In other words, the protruding portion 53D may be separated in the thickness direction T from the second inner surface 10b.

[0310] Other features of the protrusion 53D are similar to those of the protrusion 51D and the protrusion 52D.

[0311] When viewed from the thickness direction T, the through hole 43D may overlap the through hole 41D or may overlap the through hole 42D.

[0312] When viewed from the thickness direction T, the through hole 43D does not necessarily overlap with the through hole 41D and the through hole 42D.

[0313] Other features of the through hole 43D are similar to those of the through holes 41D and 42D.

[0314] As shown in Figures 11, 12, and 13, in each wick layer, there are curved portions between the through holes (including the first through hole 41, the second through hole 42, the third through hole 43, etc.).

[0315] 11 and 12, when the distance between the end R2 of the second through hole 42 on the first inner surface 10a side and the second inner surface 10b in the thickness direction T is D2, it is preferable that the relationship A2≧D2 is satisfied. In the example shown in FIG. 11 and FIG. 12, the relationship A2>D2 is satisfied.

[0316] 11 and 12, in the thickness direction T, it is preferable that the end 53a on the first inner surface 10a side of the protrusion 53 located on the periphery of the third through hole 43 is located at the same height as the end R2 on the first inner surface 10a side of the second through hole 42, or is located at a height on the first inner surface 10a side higher than the end R2 on the first inner surface 10a side of the second through hole 42. In the example shown in Fig. 11 and 12, in the thickness direction T, the end 53a on the first inner surface 10a side of the protrusion 53 is located at a height on the first inner surface 10a side higher than the end R2 on the first inner surface 10a side of the second through hole 42.

[0317] In the vapor chamber 4, the third through hole 43 overlaps with the second through hole 42 so as to satisfy the above-mentioned distance (height) relationship, so that the liquid phase working medium 20 contained in the third wick layer 33, preferably the liquid phase working medium 20 contained in the region between the third wick layer 33 and the second inner surface 10b, evaporates and changes to the gas phase working medium 20 through the third through hole 43, the second through hole 42, and further the first through hole 41, and moves sufficiently to the vapor flow path. As a result, in the vapor chamber 4, the maximum heat transport amount is easily improved sufficiently.

[0318] 11 and 12, when the distance between the end R1 of the first through hole 41 on the first inner surface 10a side and the second inner surface 10b in the thickness direction T is D1, it is preferable that the relationship A2≧D1 is satisfied. In the example shown in FIG. 11 and FIG. 12, the relationship A2>D1 is satisfied.

[0319] In other words, as shown in FIGS. 11 and 12, in the thickness direction T, the end portion 53a on the first inner surface 10a side of the protruding portion 53 located at the periphery of the third through hole 43 is preferably positioned at the same height as the end portion R1 on the first inner surface 10a side of the first through hole 41 or at a height closer to the first inner surface 10a side than the end portion R1 on the first inner surface 10a side of the first through hole 41. In the examples shown in FIGS. 11 and 12, in the thickness direction T, the end portion 53a on the first inner surface 10a side of the protruding portion 53 is positioned at a height closer to the first inner surface 10a side than the end portion R1 on the first inner surface 10a side of the first through hole 41.

[0320] In the vapor chamber 4, the third through hole 43 overlaps with the second through hole 42 and further with the first through hole 41 so as to satisfy the above-described distance (height) relationship. As a result, the liquid-phase working medium 20 contained in the third wick layer 33, preferably the liquid-phase working medium 20 contained in the region between the third wick layer 33 and the second inner surface 10b, easily moves sufficiently into the vapor flow path while evaporating and changing into the vapor-phase working medium 20 through the third through hole 43, the second through hole 42, and further the first through hole 41. As a result, in the vapor chamber 4, the maximum heat transport amount is likely to be sufficiently improved.

[0321] In the examples shown in FIGS. 11 and 12, the relationship of D1 < D2 is satisfied, but the relationship of D1 = D2 or the relationship of D1 > D2 may be satisfied. In other words, in the examples shown in FIGS. 11 and 12, the end portion R1 on the first inner surface 10a side of the first through hole 41 is positioned at a height closer to the second inner surface 10b side than the end portion R2 on the first inner surface 10a side of the second through hole 42, but the end portion R1 on the first inner surface 10a side of the first through hole 41 may be positioned at the same height as the end portion R2 on the first inner surface 10a side of the second through hole 42 or at a height closer to the first inner surface 10a side than the end portion R2 on the first inner surface 10a side of the second through hole 42.

[0322] <Embodiment 5> In the heat diffusion devices of the first to fourth embodiments of the present invention, a portion of the inner surface of the protrusion located on the periphery of the first through hole is in contact with a portion of the outer surface of the protrusion located on the periphery of the second through hole. However, the entire inner surface of the protrusion located on the periphery of the first through hole may be in contact with at least a portion of the outer surface of the protrusion located on the periphery of the second through hole.

[0323] The heat diffusion device of embodiment 5 of the present invention is different from the heat diffusion device of embodiment 1 of the present invention in that the entire inner surface of the protrusion located on the periphery of the first through hole is in contact with at least a portion of the outer surface of the protrusion located on the periphery of the second through hole.

[0324] Fig. 14 is a schematic cross-sectional view showing an example of a cross section of the heat spreading device according to the fifth embodiment of the present invention, Fig. 15 is a schematic cross-sectional view showing an enlarged portion of the heat spreading device shown in Fig. 14.

[0325] FIG. 14 shows a cross section taken at a position corresponding to FIG.

[0326] 14, the entire inner surface of the protruding portion 51 located on the periphery of the first through hole 41 contacts at least a part of the outer surface of the protruding portion 52 located on the periphery of the second through hole 42. In the example shown in FIGS. 14 and 15, the entire inner surface of the protruding portion 51 contacts the entire outer surface of the protruding portion 52.

[0327] In the vapor chamber 5, the entire inner surface of the protrusion 51 is in contact with at least a portion of the outer surface of the protrusion 52, so that the first wick layer 31 and the second wick layer 32 are more firmly crimped by the protrusion 51 and the protrusion 52, thereby further increasing the bonding strength between the two.

[0328] Furthermore, in the vapor chamber 5, the entire inner surface of the protruding portion 51 is in contact with at least a part of the outer surface of the protruding portion 52, so that the protruding portion 51 can be configured to be embedded in the second wick layer 32 as shown in Figures 14 and 15. Therefore, in the vapor chamber 5, the vapor flow path between the first wick layer 31 and the first inner surface 10a is wider by the amount that the protruding portion 51 is embedded in the second wick layer 32 compared to the vapor chamber 1, so that the thermal diffusivity is more likely to be improved, and as a result, the maximum heat transport amount is more likely to be improved.

[0329] Furthermore, in the vapor chamber 5, the dimension of the wick 30 in the thickness direction T is smaller than that of the vapor chamber 1 by the amount that the protrusion 51 is embedded on the second wick layer 32 side, making it possible to make the vapor chamber thinner.

[0330] <Embodiment 6> The heat diffusion device of embodiment 6 of the present invention is different from the heat diffusion device of embodiment 3 of the present invention in that the entire inner surface of the protrusion located on the periphery of the first through hole is in contact with at least a portion of the outer surface of the protrusion located on the periphery of the second through hole.

[0331] Fig. 16 is a schematic cross-sectional view showing an example of a cross section of a heat spreading device according to embodiment 6 of the present invention Fig. 17 is a schematic cross-sectional view showing an enlarged portion of the heat spreading device shown in Fig. 16 .

[0332] FIG. 16 shows a cross section taken at a position corresponding to FIG.

[0333] 16, the entire inner surface of the protruding portion 51 located on the periphery of the first through hole 41 contacts at least a part of the outer surface of the protruding portion 52 located on the periphery of the second through hole 42. In the example shown in FIGS. 16 and 17, the entire inner surface of the protruding portion 51 contacts a part of the outer surface of the protruding portion 52.

[0334] In the vapor chamber 6, the entire inner surface of the protrusion 51 is in contact with at least a portion of the outer surface of the protrusion 52, so that the first wick layer 31 and the second wick layer 32 are more firmly crimped by the protrusion 51 and the protrusion 52, thereby further increasing the bonding strength between the two.

[0335] Furthermore, in the vapor chamber 6, the entire inner surface of the protruding portion 51 is in contact with at least a part of the outer surface of the protruding portion 52, so that the protruding portion 51 can be configured to be embedded in the second wick layer 32 side as shown in Figures 16 and 17. Therefore, in the vapor chamber 6, the vapor flow path between the first wick layer 31 and the first inner surface 10a is wider by the amount that the protruding portion 51 is embedded in the second wick layer 32 side compared to the vapor chamber 3, so that the thermal diffusivity is more likely to be improved, and as a result, the maximum heat transport amount is more likely to be improved.

[0336] Furthermore, in the vapor chamber 6, the dimension of the wick 30 in the thickness direction T is smaller than that of the vapor chamber 3 by the amount that the protrusion 51 is embedded on the second wick layer 32 side, making it possible to make the vapor chamber thinner.

[0337] <Other embodiments> The heat spreading device of the present invention may have the following embodiments other than the first to sixth embodiments.

[0338] The heat spreading devices of the second and fourth embodiments of the present invention may be configured so that the entire inner surface of the protrusion located on the periphery of the first through hole is in contact with at least a part of the outer surface of the protrusion located on the periphery of the second through hole.

[0339] The heat spreading devices of the second and fourth embodiments of the present invention may be configured so that the entire inner surface of the protrusion located on the periphery of the second through hole is in contact with at least a part of the outer surface of the protrusion located on the periphery of the third through hole.

[0340] The number of wick layers may be 4 or more in the heat diffusion devices of the first to sixth embodiments of the present invention (the number of wick layers is 2 or 3). That is, the number of wick layers is not particularly limited in the heat diffusion device of the present invention.

[0341] As described above, in a conventional vapor chamber in which multiple wick layers are stacked, the driving force for driving the liquid phase working medium is likely to be weak, particularly in a wick layer far from the vapor flow path, so that the liquid phase working medium may be difficult to move. This problem tends to become more pronounced as the number of stacked wick layers increases, and for example, tends to become more pronounced in a wick layer farther from the vapor flow path.

[0342] In contrast, according to the heat diffusion device of the present invention, even if the number of wick layers is increased to 2, 3, 4, 5, 6, etc. within the range of the thickness direction dimension of the internal space of the housing, the driving force for driving the liquid phase working medium is ensured even in the wick layer far from the vapor flow path by the same mechanism as in the heat diffusion device of the present invention in the first to sixth embodiments. Therefore, according to the heat diffusion device of the present invention, by increasing the number of wick layers, the cross-sectional area of ​​the region where the liquid flow path permeates the wick is increased, and the maximum heat transport amount can be significantly improved.

[0343] In the heat diffusion devices according to the first to sixth embodiments of the present invention, the first wick layer is located closest to the first inner surface in the thickness direction of the wick, but the first wick layer does not have to be located closest to the first inner surface in the thickness direction of the wick. For example, at least one wick layer may be further laminated on the first inner surface side of the first wick layer.

[0344] In the heat diffusion devices according to the first to sixth embodiments of the present invention, the second wick layer or the third wick layer is located closest to the second inner surface in the thickness direction of the wick, but the second wick layer or the third wick layer does not have to be located closest to the second inner surface in the thickness direction of the wick. For example, at least one wick layer may be further laminated on the second inner surface side of the second wick layer or the third wick layer.

[0345] [Electronic equipment] The electronic device of the present invention is characterized by comprising the heat spreading device of the present invention.

[0346] In the following, as an example of the electronic device of the present invention, an electronic device having the heat spreading device of the first embodiment of the present invention will be described. The same applies to electronic devices having the heat spreading devices of the other embodiments of the present invention.

[0347] FIG. 18 is a schematic perspective view showing an example of an electronic device of the present invention.

[0348] The electronic device 100 shown in FIG.

[0349] As shown in FIG. 18, the electronic device 100 preferably further includes an electronic component 110.

[0350] 18, the electronic component 110 is preferably provided on the outer surface of the housing 10 of the vapor chamber 1. In this case, the vapor chamber 1 can function as the electronic component 110 serving as the heat source HS shown in FIG.

[0351] The electronic component 110 may be provided on the outer surface of the housing 10 of the vapor chamber 1 shown in FIG. 3 opposite the first inner surface 10a of the housing 10, here the outer surface of the first sheet 11, or on the outer surface of the housing 10 opposite the second inner surface 10b, here the outer surface of the second sheet 12.

[0352] The electronic component 110 may be provided directly on the outer surface of the housing 10, or may be provided via another member such as a highly thermally conductive adhesive, sheet, or tape.

[0353] When electronic component 110 is provided on the outer surface of housing 10, it is preferable that electronic component 110 overlaps evaporation part EP when viewed from the thickness direction T.

[0354] Examples of the electronic components 110 include heat generating elements such as a central processing unit (CPU), a light emitting diode (LED), and a power semiconductor.

[0355] As shown in FIG. 18, the electronic device 100 preferably further includes a device housing 120.

[0356] In the example shown in FIG. 18, the vapor chamber 1 and the electronic component 110 are provided in the internal space of a device housing 120.

[0357] The housing 10 and the device housing 120 are preferably joined via a joining member. More specifically, the outer surface of the housing 10 and the inner surface of the device housing 120 are preferably joined via a joining member. In this case, the adhesion between the housing 10 and the device housing 120 is improved.

[0358] The joining member joining the housing 10 and the device housing 120 is preferably a thermally conductive member. In this case, heat from the heat source HS, in this case, heat from the electronic component 110, is easily conducted from the housing 10 to the device housing 120. In other words, the path from the housing 10 to the device housing 120 also makes it easier for the heat from the heat source HS, in this case, heat from the electronic component 110, to diffuse.

[0359] Examples of the thermally conductive member include a thermally conductive tape and a thermally conductive adhesive.

[0360] As described above, the vapor chamber 1 operates autonomously without requiring an external power source, and furthermore, by utilizing the latent heat of evaporation and latent heat of condensation of the working medium 20, it is possible to diffuse heat from the heat source HS, in this case, from the electronic component 110, two-dimensionally at high speed. From the above, the electronic device 100 having the vapor chamber 1 can effectively realize heat dissipation in the limited space inside the electronic device 100.

[0361] The present specification discloses the following:

[0362] <1> a housing having a first inner surface and a second inner surface opposed to each other in a thickness direction and having an internal space; A working medium sealed in the internal space of the housing; and a wick provided in the internal space of the housing, The wick includes a first wick layer and a second wick layer adjacent to the second inner surface side of the first wick layer in the thickness direction, The first wick layer is provided with a first through hole in the thickness direction, The second wick layer is provided with a second through hole having a protruding portion located on a periphery thereof, the protruding portion approaching the first inner surface in the thickness direction, When viewed from the thickness direction, the second through hole overlaps with the first through hole, a distance in the thickness direction between an end portion of the protrusion located on the periphery of the second through hole on the first inner surface side and the second inner surface is A1, and a distance between an end portion of the first through hole on the second inner surface side and the second inner surface is B1, satisfying a relationship A1 ≧ B1.

[0363] <2> In addition to the first through hole, the first wick layer is further provided with a through hole that does not overlap with the second through hole when viewed from the thickness direction, In the thickness direction, when a distance between an end portion of the through hole other than the first through hole of the first wick layer on the first inner surface side and the second inner surface is C1, a relationship of A1 ≧ C1 is satisfied. <1> 2. A heat spreading device as described in claim 1.

[0364] <3> When a distance between an end of the first through hole on the first inner surface side and the second inner surface in the thickness direction is D1, a relationship of A1 ≧ D1 is satisfied. <1> or <2> 2. A heat spreading device as described in claim 1.

[0365] <4> A protrusion is located on the periphery of the first through hole and approaches the first inner surface in the thickness direction. <1> ~ <3> 2. A heat spreading device according to claim 1 .

[0366] <5> At least a part of an inner surface of the protrusion located on the periphery of the first through hole is in contact with at least a part of an outer surface of the protrusion located on the periphery of the second through hole. <4> 2. A heat spreading device as described in claim 1.

[0367] <6> The entire inner surface of the protrusion located on the periphery of the first through hole is in contact with at least a part of the outer surface of the protrusion located on the periphery of the second through hole. <5> 2. A heat spreading device as described in claim 1.

[0368] <7> The first wick layer is located closest to the first inner surface in the thickness direction of the wick, The second wick layer is located closest to the second inner surface in the thickness direction of the wick. <1> ~ <6> 2. A heat spreading device according to claim 1 .

[0369] <8> The wick further includes a third wick layer adjacent to the second inner surface side of the second wick layer in the thickness direction. <1> ~ <6> 2. A heat spreading device according to claim 1 .

[0370] <9> The third wick layer is provided with a third through hole having a protruding portion located on a periphery thereof, the protruding portion approaching the first inner surface in the thickness direction, When viewed from the thickness direction, the third through hole overlaps with the second through hole, In the thickness direction, when a distance between an end portion on the first inner surface side of the protrusion located on the periphery of the third through hole and the second inner surface is A2, and a distance between an end portion on the second inner surface side of the second through hole and the second inner surface is B2, a relationship of A2 ≧ B2 is satisfied. <8> 2. A heat spreading device as described in claim 1.

[0371] <10> In addition to the second through hole, the second wick layer is further provided with a through hole that does not overlap with the third through hole when viewed from the thickness direction, In the thickness direction, when the distance between the end of the through hole other than the second through hole of the second wick layer on the first inner surface side and the second inner surface is C2, the relationship A2 ≧ C2 is satisfied. <9> 2. A heat spreading device as described in claim 1.

[0372] <11> When a distance in the thickness direction between an end of the second through hole on the first inner surface side and the second inner surface is defined as D2, a relationship of A2 ≧ D2 is satisfied. <9> or <10> 2. A heat spreading device as described in claim 1.

[0373] <12> A2≧B1 is satisfied. <9> ~ <11> 2. A heat spreading device according to claim 1 .

[0374] <13> In addition to the first through hole, the first wick layer is further provided with a through hole that does not overlap with the second through hole when viewed from the thickness direction, In the thickness direction, when the distance between the end of the through hole other than the first through hole of the first wick layer on the first inner surface side and the second inner surface is C1, the relationship A2 ≧ C1 is satisfied. <12> 2. A heat spreading device as described in claim 1.

[0375] <14> When a distance in the thickness direction between an end of the first through hole on the first inner surface side and the second inner surface is defined as D1, a relationship of A2≧D1 is satisfied. <12> or <13> 2. A heat spreading device as described in claim 1.

[0376] <15> The first wick layer is located closest to the first inner surface in the thickness direction of the wick, The third wick layer is located closest to the second inner surface in the thickness direction of the wick. <8> ~ <14> 2. A heat spreading device according to claim 1 .

[0377] <16> In the thickness direction, the distance between the wick and the first inner surface is greater than the distance between the wick and the second inner surface; <1> ~ <15> 2. A heat spreading device according to claim 1 .

[0378] <17> <1> ~ <16> 13. An electronic device comprising the heat spreading device according to claim 12. [Industrial Applicability]

[0379] The heat spreading device of the present invention can be used for a wide range of applications in the field of mobile information terminals, etc. For example, the heat spreading device of the present invention can be used to lower the temperature of a heat source such as a central processing unit, thereby extending the operating time of electronic devices, and can be used in electronic devices such as smartphones, tablet terminals, notebook computers, game consoles, and wearable devices. [Explanation of symbols]

[0380] 1, 2, 3, 4, 5, 6 Vapor chamber (heat diffusion device) 10. Chassis 10a First inner surface 10b Second inner surface 11 Sheet 1 12 2nd Sheet 20 Working medium 30 Wick 31 First Wick Layer 32 Second wick layer 33 Third Wick Layer 41 First through hole 42 Second through hole 43 Third Through Hole 41A, 41B, 41C, 41D, 42A, 42B, 42C, 42D, 43A, 43B, 43C, 43D through hole 51, 51A, 51C, 51D, 52, 52A, 52C, 52D, 53, 53A, 53C, 53D Protrusion 52a: an end portion on the first inner surface side of a protrusion located on the periphery of the second through hole of the second wick layer 53a: an end portion on the first inner surface side of a protrusion located on the periphery of the third through hole of the third wick layer 100 Electronic equipment 110 Electronic Components 120 Equipment housing A1: Distance between the end of the protrusion located on the periphery of the second through hole of the second wick layer on the first inner surface side and the second inner surface A2: Distance between the end of the protrusion located on the periphery of the third through hole of the third wick layer on the first inner surface side and the second inner surface B1: Distance between the end of the first through hole of the first wick layer on the second inner surface side and the second inner surface B2: Distance between the end of the second through hole of the second wick layer on the second inner surface side and the second inner surface C1: Distance between the end of the through hole on the first inner surface side other than the first through hole of the first wick layer and the second inner surface C2: Distance between the end of the through hole other than the second through hole of the second wick layer on the first inner surface side and the second inner surface D1: Distance between the end of the first through hole of the first wick layer on the first inner surface side and the second inner surface D2: Distance between the end of the second through hole of the second wick layer on the first inner surface side and the second inner surface EP Evaporation Section HS heat source L Length direction P1: End of the first through hole of the first wick layer on the second inner surface side P2: End of the second through hole of the second wick layer on the second inner surface side Q1: End of the through hole on the first inner surface side of the through hole other than the first through hole of the first wick layer Q2 Ends of the through holes on the first inner surface side other than the second through holes of the second wick layer R1: End of the first through hole of the first wick layer on the first inner surface side R2: End of the second through hole of the second wick layer on the first inner surface side T thickness direction W Width direction

Claims

1. a housing having a first inner surface and a second inner surface opposed to each other in a thickness direction and having an internal space; A working medium sealed in the internal space of the housing; and a wick provided in the internal space of the housing, The wick includes a first wick layer and a second wick layer adjacent to the second inner surface side of the first wick layer in the thickness direction, The first wick layer is provided with a first through hole in the thickness direction, The second wick layer is provided with a second through hole having a protruding portion located on a periphery thereof, the protruding portion approaching the first inner surface in the thickness direction, When viewed from the thickness direction, the second through hole overlaps with the first through hole, a distance between the end of the protrusion located on the periphery of the second through hole on the first inner surface side and the second inner surface in the thickness direction is A1, and a distance between the end of the first through hole on the second inner surface side and the second inner surface is B1, satisfying the relationship A1 ≧ B1.

2. In addition to the first through hole, the first wick layer is further provided with a through hole that does not overlap the second through hole when viewed from the thickness direction, The heat spreading device of claim 1 , wherein when the distance in the thickness direction between the end of the through hole other than the first through hole of the first wick layer on the first inner surface side and the second inner surface is C1, the relationship A1 ≧ C1 is satisfied.

3. 2 . The heat spreading device according to claim 1 , wherein when a distance D1 is defined as a distance between an end of the first through hole on the first inner surface side and the second inner surface in the thickness direction, a relationship A1≧D1 is satisfied.

4. 4. The heat spreading device according to claim 1, wherein a protrusion is located on a periphery of said first through hole, said protrusion approaching said first inner surface in said thickness direction.

5. The heat spreading device according to claim 4 , wherein at least a portion of an inner surface of the protrusion located on the periphery of the first through hole is in contact with at least a portion of an outer surface of the protrusion located on the periphery of the second through hole.

6. The heat spreading device according to claim 5 , wherein an entire inner surface of the protrusion located on the periphery of the first through hole is in contact with at least a portion of an outer surface of the protrusion located on the periphery of the second through hole.

7. The first wick layer is located closest to the first inner surface in the thickness direction of the wick, The heat spreading device according to claim 1 , wherein the second wick layer is located closest to the second inner surface in the thickness direction of the wick.

8. The heat spreading device according to claim 1 , wherein the wick further includes a third wick layer adjacent to the second inner surface side of the second wick layer in the thickness direction.

9. The third wick layer is provided with a third through hole having a protruding portion located on a periphery thereof, the protruding portion approaching the first inner surface in the thickness direction, When viewed from the thickness direction, the third through hole overlaps with the second through hole, 9. The heat spreading device of claim 8, wherein when a distance in the thickness direction between an end portion on the first inner surface side of the protrusion located on the periphery of the third through hole and the second inner surface is A2 and a distance between an end portion on the second inner surface side of the second through hole and the second inner surface is B2, a relationship of A2 ≧ B2 is satisfied.

10. In addition to the second through hole, the second wick layer is further provided with a through hole that does not overlap with the third through hole when viewed from the thickness direction, The heat spreading device of claim 9, wherein when the distance in the thickness direction between the end of the through hole other than the second through hole of the second wick layer on the first inner surface side and the second inner surface is C2, the relationship A2 ≧ C2 is satisfied.

11. The heat spreading device according to claim 9 , wherein when a distance in the thickness direction between an end of the second through hole on the first inner surface side and the second inner surface is defined as D2, a relationship of A2≧D2 is satisfied.

12. The heat spreading device of claim 9 , wherein the relationship A2≧B1 is satisfied.

13. In addition to the first through hole, the first wick layer is further provided with a through hole that does not overlap the second through hole when viewed from the thickness direction, The heat spreading device of claim 12, wherein when the distance in the thickness direction between the end of the through hole other than the first through hole of the first wick layer on the first inner surface side and the second inner surface is C1, the relationship A2 ≧ C1 is satisfied.

14. The heat spreading device according to claim 12 , wherein when a distance in the thickness direction between an end of the first through hole on the first inner surface side and the second inner surface is defined as D1, a relationship of A2≧D1 is satisfied.

15. The first wick layer is located closest to the first inner surface in the thickness direction of the wick, The heat spreading device according to claim 8 , wherein the third wick layer is located closest to the second inner surface in the thickness direction of the wick.

16. The heat spreading device of claim 1 , wherein in the thickness direction, a distance between the wick and the first inner surface is greater than a distance between the wick and the second inner surface.

17. 4. An electronic device comprising the heat spreading device according to claim 1.

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