JP2020008202A - Vapor chamber and electronic apparatus - Google Patents

Abstract

To provide a vapor chamber which can obtain high heat transfer ability even when being thinned, and can suppress destruction.SOLUTION: A vapor chamber has a sealed space in which a working fluid is enclosed. The sealed space is provided with condensate flow passages through which the working fluid moves in a state of a condensed liquid, and vapor flow passages each having a larger flow passage cross-sectional area than that of the condensate flow passage, in which the working fluid undergoes self-excited oscillation in a state of vapor and condensed liquid. In the condensate flow passages, the plurality of straight condensate flow passages are disposed between two vapor flow passages, in which the plurality of straight condensate flow passages are in communication with one another. The structure of an area in which the vapor flow passages and the condensate flow passages are disposed is configured to be symmetrical with respect to a line parallel to the condensate flow passages that are disposed in a straight line manner.SELECTED DRAWING: Figure 15

Description

  The present invention relates to a vapor chamber in which a working fluid sealed in a closed space performs heat transfer while self-excitedly vibrating with a phase change.

2. Description of the Related Art Electronic components such as personal computers and mobile terminals such as mobile phones and tablet terminals use electronic components such as a central processing unit (CPU). Since the amount of heat generated from such electronic components tends to increase due to the improvement in information processing capability, a technique for cooling the heat is important.
Heat pipes are well known as a means for cooling. In this method, the working fluid enclosed in the pipe uses the phase change to transport the heat in the heat source to another portion to diffuse the heat, thereby cooling the heat source.

  On the other hand, in recent years, the thickness of these electronic devices has been remarkably reduced, and a cooling means thinner than a conventional heat pipe has been required. On the other hand, a vapor chamber has been proposed. The vapor chamber is also called a sheet-type heat pipe, and is a device in which the concept of heat transport by the heat pipe is developed to a flat member. That is, in the vapor chamber, the working fluid is sealed between the opposed flat plates, and the heat in the heat source is transported and diffused by utilizing the phase change of the working fluid to cool the heat source.

  As such a heat pipe or a vapor chamber, a capillary force type as in Patent Document 1, a self-excited vibration type as in Patent Document 2, and a composite type of both as in Patent Document 3 are used by the driving force of the movement of the working fluid. Proposed.

JP 2009-076650 A International Publication No. WO2016 / 035436 JP 2003-302180 A

One of the drawbacks of the heat pipe and the vapor chamber in which the heat transport ability cannot be exhibited is a dryout in the evaporating section. This is because the working fluid undergoes a phase change from liquid to vapor due to the heat, so that the liquid is not appropriately supplied to the portion where the heat source is to be cooled, so that the phase change cannot occur and the heat source cannot be cooled. Is to be in a state.
As described above, in recent years, the thickness of electronic devices has been remarkably reduced, and dry-out is likely to occur due to the demand for thinner and smaller heat pipes and vapor chambers. And even with the conventional heat pipes and vapor chambers described above, this dry-out could not be sufficiently avoided.

  In addition, electronic devices including a heat pipe and a vapor chamber are assumed to be used in various environments, including an environment below freezing. In a vapor chamber using a working fluid, the working fluid may freeze in an environment below the freezing point. When the working fluid freezes, the volume increases. As a result, the frozen working fluid pushes the two flat plates constituting the vapor chamber in a direction in which the two flat plates are separated from each other to apply a force, so that the wall connecting the two flat plates is broken. is there. Such destruction is rarely caused by a single freezing of the working fluid, but due to repetition of freezing and melting of the working fluid, plastic deformation accumulates and finally breaks due to the breakage of the wall. The rupture causes a leakage of the working fluid, which may cause a short circuit of the surrounding electronic components and may cause a failure of the electronic device. In order to prevent such destruction, for example, a space serving as a buffer for volume expansion is provided in a space in which the working fluid is sealed. However, such a space is not preferable from the viewpoint of reducing the thickness and improving the performance of the vapor chamber (improving the heat transport capability), and may rather impair the performance.

  In view of the above problems, an object of the present invention is to provide a vapor chamber capable of obtaining high heat transfer capability even when the thickness is reduced and suppressing destruction. Further, an electronic device provided with the vapor chamber is provided.

  One embodiment of the present invention is a vapor chamber in which a closed space is formed between a plurality of sheets, and a working fluid is sealed in the closed space, wherein the working fluid is in a condensed liquid state in the closed space. A condensate flow path, which is a flow path that moves in, and a steam flow path that has a larger flow path cross-sectional area than the condensate flow path and the working fluid self-oscillates in a state of steam and condensate, The condensate flow path has a plurality of linear condensate flow paths disposed between two vapor flow paths, the plurality of vapor flow paths are in communication, and the vapor flow path and the condensate flow path are disposed. The vapor chamber is configured such that the structure in the region is symmetrical about a line parallel to the condensate flow path arranged in a straight line.

  The plurality of steam channels may be formed so as to communicate with each other.

  The structure in the region where the vapor flow path and the condensate flow path are arranged may be further configured to be symmetrical with respect to a line orthogonal to the condensate flow path arranged linearly.

  Further, an annular condensate flow path may be provided along the edge of the closed space.

  The vapor chamber may have a thickness of 0.4 mm or less.

  Another embodiment of the present invention includes a housing, an electronic component disposed inside the housing, and the vapor chamber disposed in contact with the electronic component directly or via another member. , Electronic equipment. In this case, the electronic component may be disposed at a position overlapping an axis defined by a line parallel to the condensate flow path arranged in a straight line in the vapor chamber when the vapor chamber is viewed in plan.

According to the present invention, in the steam flow path, the working fluid moves by self-excited vibration, heat is efficiently moved and diffused, and the condensed liquid flow path is provided separately from the steam flow path. Since the condensed liquid can be efficiently moved and refluxed by the capillary force, it is possible to suppress the occurrence of dryout.
In addition, since the vapor flow path and the condensate flow path are arranged symmetrically, the self-excited vibration is balanced and the vibration is stabilized during operation of the vapor chamber, so that high heat transport capability can be stably exhibited. . On the other hand, when the vapor chamber is not operating, the condensate is dispersed throughout the vapor chamber and is prevented from concentrating at one location, so that even if the working fluid freezes and expands, the vapor chamber is destroyed. Can be prevented.
Therefore, even if the working fluid is used in an environment where the working fluid freezes, the thickness, the heat transport ability, and the durability are all satisfied.

FIG. 1A is a perspective view of the vapor chamber 1, and FIG. 1B is an exploded perspective view of the vapor chamber 1. FIG. 2A is a perspective view of the first sheet 10, and FIG. 2B is a plan view of the first sheet 10. FIG. 3 is a cut surface of the first sheet 10. FIGS. 4A and 4B show another cut surface of the first sheet 10. FIG. 5 is an enlarged view of a part of the outer peripheral liquid flow path portion 14 in plan view. FIGS. 6A to 6C are diagrams showing other forms of walls and liquid communication openings. FIG. 7 is a partially enlarged view of another example of the outer peripheral liquid flow path portion 14 when viewed from above. FIG. 8A is a cross-sectional view focusing on the inner liquid flow path 15, and FIG. 8B is an enlarged view of a part of the inner liquid flow path 15 in plan view. FIG. 9A is a perspective view of the second sheet 20, and FIG. 9B is a plan view of the second sheet 20. FIG. 10 is a cut surface of the second sheet 20. FIG. 11 is another cut surface of the second sheet 20. FIG. 12 shows a cut surface of the vapor chamber 1. FIG. 13 is an enlarged view of a part of FIG. FIG. 14 is a cross-sectional view along XIV-XIV in FIG. FIG. 15 is a diagram illustrating the structure of the closed space 2 of the vapor chamber 1 and is a diagram illustrating symmetry. FIG. 16 is a perspective view illustrating the electronic device 40. FIG. 17 is a view for explaining the operation of the vapor chamber 1. FIG. 18A is a perspective view of the second sheet 120, and FIG. 18B is a view for explaining the structure of the closed space of the vapor chamber 101. FIG. 19A is a perspective view of the second sheet 120 ′, and FIG. 19B is a view for explaining the structure of the closed space of the vapor chamber 101 ′. FIG. 20A is a diagram illustrating the structure of the closed space of the vapor chamber 201, and FIG. 20B is a part of a cut surface of the vapor chamber 201. FIG. 21 is a view for explaining the structure of the closed space 302 of the vapor chamber 301, and is a view showing that the steam flow path communicates with other steam flow paths at both ends. FIG. 22 is an external perspective view of the vapor chamber 401. FIG. 23 is an exploded perspective view of the vapor chamber 401. FIG. 24A is a diagram of the third sheet 430 viewed from one surface, and FIG. 24B is a diagram of the third sheet 430 viewed from the other surface. FIG. 25 is a cut surface of the third sheet 430. FIG. 26 is another cut surface of the third sheet 430. FIG. 27 shows a cut surface of the vapor chamber 401. FIG. 28 is an enlarged view of a part of FIG. FIG. 29 shows another cut surface of the vapor chamber 401.

  Hereinafter, the present invention will be described based on embodiments shown in the drawings. However, the present invention is not limited to these modes. In the drawings described below, the size and ratio of members may be changed or exaggerated for simplicity. In addition, for the sake of simplicity, parts that are not necessary for the description may be omitted from the drawings or symbols.

  FIG. 1A is an external perspective view of the vapor chamber 1 according to the first embodiment, and FIG. 1B is an exploded perspective view of the vapor chamber 1. Arrows (x, y, z) indicating directions orthogonal to each other are also shown in these drawings and each of the drawings described below for convenience as needed. Here, the direction in the xy plane is a direction along the plate surface of the vapor chamber 1 having a flat plate shape, and the z direction is a thickness direction.

  The vapor chamber 1 has a first sheet 10 and a second sheet 20, as can be seen from FIGS. 1 (a) and 1 (b). Then, as will be described later, the first sheet 10 and the second sheet 20 are overlapped and joined (diffusion bonding, brazing, etc.), so that the first sheet 10 and the second sheet 20 are separated from each other. A closed space 2 is formed (see, for example, FIG. 12), and a working fluid is sealed in the closed space 2.

In the present embodiment, the first sheet 10 is a sheet-like member as a whole. 2A is a perspective view of the first sheet 10 viewed from the inner surface 10a side, and FIG. 2B is a plan view of the first sheet 10 viewed from the inner surface 10a side. FIG. 3 shows a cut surface of the first sheet 10 when cut along the line III-III in FIG. 2B.
The first sheet 10 includes an inner surface 10a, an outer surface 10b opposite to the inner surface 10a, and a side surface 10c that forms a thickness across the inner surface 10a and the outer surface 10b, and a flow in which the working fluid moves to the inner surface 10a side. A pattern for the road is formed. As described later, the closed space 2 is formed by overlapping the inner surface 10a of the first sheet 10 and the inner surface 20a of the second sheet 20 so as to face each other.

Such a first sheet 10 includes a main body 11 and an injection section 12. The main body 11 is in the form of a sheet that forms a portion where the working fluid moves, and in the present embodiment, is a rectangle having a circular arc (so-called R) in plan view.
The injection part 12 is a part for injecting the working fluid into the closed space 2 (see, for example, FIG. 12) formed by the first sheet 10 and the second sheet 20. The sheet is a quadrangular sheet in plan view that protrudes from the sheet. In this embodiment, the injection portion 12 of the first sheet 10 has a flat surface on both the inner surface 10a and the outer surface 10b.

The thickness of the first sheet 10 is not particularly limited, but is preferably 0.1 mm or more and 1.0 mm or less. This can increase the number of scenes that can be applied as a thin vapor chamber.
Further, the material forming the first sheet 10 is not particularly limited, but is preferably a metal having high thermal conductivity. This includes, for example, copper and copper alloy. In particular, by using copper and a copper alloy, it becomes easy to manufacture a vapor chamber by etching and diffusion bonding as described later while improving the heat transport ability.

  On the inner surface 10a side of the main body 11, a structure for moving the working fluid is formed. Specifically, on the inner surface 10a side of the main body 11, an outer peripheral joint portion 13, an outer peripheral liquid passage portion 14, an inner liquid passage portion 15, a vapor passage groove 16, and a vapor passage communication groove 17 are provided. It is configured.

The outer peripheral joint portion 13 is a surface formed on the inner surface 10 a side of the main body 11 along the outer periphery of the main body 11. The outer peripheral joint 13 overlaps the outer peripheral joint 23 of the second sheet 20 and is joined (diffusion-bonded, brazed, or the like) to form the closed space 2 between the first sheet 10 and the second sheet 20. The working fluid is sealed therein.
FIG. 2 (b), the can be set appropriately as required width of the outer peripheral joint 13 shown in _{A 10} in FIG. 3, is preferably 0.8mm or more 3.0mm or less. If the width is smaller than 0.8 mm, there is a possibility that the joining area becomes insufficient when the first sheet and the second sheet are displaced during joining. On the other hand, if the width is larger than 3.0 mm, the internal volume of the closed space becomes small, and there is a possibility that the steam flow path and the condensate flow path cannot be sufficiently secured.

  In the outer peripheral joint portion 13, holes 13a penetrating in the thickness direction (z direction) are provided at the four corners of the main body 11. This hole functions as a positioning means at the time of superposition with the second sheet 20.

  The outer peripheral liquid flow path portion 14 functions as a liquid flow path portion, and is a portion that constitutes a part of the condensed liquid flow path 3 (see, for example, FIG. 13) that is a flow path that passes when the working fluid is condensed and liquefied. is there. FIG. 4A illustrates a portion indicated by an arrow IVa in FIG. 3, and FIG. 4B illustrates a cut surface along IVb-IVb in FIG. 2B. In each of the figures, the cross-sectional shape of the outer peripheral liquid flow path portion 14 appears. FIG. 5 is an enlarged view of the outer peripheral liquid flow path portion 14 viewed from the direction indicated by the arrow V in FIG.

As can be seen from these figures, the outer peripheral liquid flow path portion 14 is formed along the inner surface of the outer peripheral joint portion 13 of the inner surface 10 a of the main body 11, and provided so as to be annular along the outer periphery of the closed space 2. I have. Further, in the outer peripheral liquid flow path portion 14, a plurality of liquid flow grooves 14a, which are grooves extending parallel to the outer peripheral direction of the main body 11, are formed, and the plurality of liquid flow grooves 14a are formed by the liquid flow grooves 14a. They are arranged at intervals in a direction different from the extending direction. Therefore, as can be seen from FIGS. 4 (a) and 4 (b), in the outer peripheral liquid flow path portion 14, a wall which is a convex portion between the liquid flow groove 14a which is a concave portion in the cross section thereof. 14b are formed by repeating irregularities.
Here, since the liquid passage groove 14a is a groove, the liquid passage groove 14a has a bottom in a cross-sectional shape thereof, and an opening formed on the opposite side facing the bottom.

  Further, by providing the plurality of liquid flow grooves 14a in this manner, the depth and width of each liquid flow groove 14a are reduced, and the flow path of the condensed liquid flow path 3 (see, for example, FIG. 13) is cut off. A large capillary force can be used by reducing the area. On the other hand, by using a plurality of liquid flow grooves 14a, an appropriate internal volume of the condensed liquid flow path 3 as a whole is secured, and a required flow rate of the condensed liquid can be supplied.

  Further, in the outer peripheral liquid flow path portion 14, as shown in FIG. 5, adjacent liquid flow path grooves 14a communicate with each other through liquid communication openings 14c provided at intervals on the wall 14b. This promotes equalization of the amount of condensed liquid between the plurality of liquid flow grooves 14a, and allows the condensed liquid to flow efficiently. In addition, a liquid communication opening 14 c provided in a wall 14 b adjacent to the steam flow channel groove 16 forming the steam flow channel 4 connects the steam flow channel 4 and the condensate flow channel 3. Therefore, by forming the liquid communication opening 14c, the condensate generated in the vapor flow path 4 can be smoothly moved to the condensate flow path 3, and the vapor generated in the condensate liquid flow path 3 can be smoothly vaporized. The fluid can be moved to the flow path 4, which can promote a smooth flow of the working fluid without hindering the self-excited oscillation of the working fluid.

FIGS. 6A to 6C show one condensate flow path 14a, two walls 14b sandwiching the same, and one liquid communication opening provided in each wall 14b from the same viewpoint as FIG. The figure which showed the part 14c was represented. In any of these, the shape of the wall 14b differs from the example of FIG. 5 at the viewpoint (plan view).
That is, the width (C ₂ ) of the wall 14b shown in FIG. 5 is the same as the other portions at the end where the liquid communication opening 14c is formed, and is constant. On the other hand, in the wall 14b having the shape shown in FIGS. 6A to 6C, the width at the end where the liquid communication opening 14c is formed is larger than the maximum width (C ₂ ) of the wall 14b. Is also reduced. More specifically, in the example of FIG. 6A, the corner is formed in an arc shape at the end, and the width of the end is reduced by forming an R at the corner. In FIG. 6B, the end is formed. FIG. 6C shows an example in which the width of the end portion is reduced due to the semicircular shape, and FIG.

As shown in FIGS. 6A to 6C, the width of the wall 14b at the end where the liquid communication opening 14c is formed is smaller than the maximum width (C ₂ ) of the wall 14b. Is formed, the working fluid easily moves through the liquid communication opening 14c, and the movement of the working fluid to the adjacent condensate flow path 3 becomes easy.

In the present embodiment, as shown in FIG. 5, the liquid communication opening 14c is disposed so as to face the same position in the direction in which the liquid flow channel 14a extends across the one liquid flow channel 14a. However, the present invention is not limited to this. For example, as shown in FIG. 7, the liquid communication openings 14c are located at different positions in the direction in which the liquid flow grooves 14a extend across the one liquid flow groove 14a. It may be arranged. That is, in this case, the liquid communication opening 14c is arranged offset.
By providing the liquid communication opening 14c offset as described above, the liquid communication opening 14c does not simultaneously appear on both sides when viewed from the working fluid traveling through the condensate flow path 3, and the liquid communication opening 14c Appears, at least one side surface always has the wall 14b. Therefore, the capillary force can be continuously obtained. By forming the liquid communication opening 14c offset from this point of view, the capillary force acting on the working fluid can be maintained at a high level, so that smoother reflux is possible.
Also, in the case where the liquid communication openings 14c are arranged in an offset manner as described above, the end shape of the wall 14b can be configured in accordance with the examples of FIGS. 6 (a) to 6 (c).

It is preferable that the outer peripheral liquid flow path section 14 having the above configuration further has the following configuration.
Width in FIG. 2 (b), FIG. 3, FIG. 4 (a), the outer peripheral fluid passage section 14 shown in B ₁₀ in FIG. 4 (b), can be appropriately set from the size of the entire vapor chamber Is preferably 0.3 mm or more and 2 mm or less. If the width is smaller than 0.3 mm, there is a possibility that a sufficient amount of liquid flowing outside cannot be obtained. If the width exceeds 2 mm, there is a possibility that sufficient space for the inner condensate flow path or vapor flow path cannot be obtained.

For liquid flow path grooves 14a, FIG. 4 (a), the 5, it is preferable groove width shown in _{C 1} in FIG. 6 (a) ~ FIG. 6 (c) is 10μm or more 300μm or less.
Also, the depth of the groove indicated by D in FIGS. 4A and 4B is preferably 5 μm or more and 200 μm or less. Thereby, the capillary force of the condensed liquid flow path necessary for flowing the liquid can be sufficiently exhibited. Here, the depth D of the groove is preferably smaller than the remaining sheet thickness obtained by subtracting the depth D of the groove from the thickness of the first sheet 10. This makes it possible to more reliably prevent the sheet from being broken when the working fluid is frozen.
From the viewpoint of more strongly exerting the capillary force of the flow path, the aspect ratio (aspect ratio) in the flow path cross section represented by C ₁ / D is preferably larger than 1.0 or smaller than 1.0. . Among them, C ₁ > D is preferable from the viewpoint of production, and the aspect ratio is preferably higher than 1.3.

Also, the walls 14b, FIG. 4 (a), the 5, it is preferable that the width indicated by _{C 2} is 20μm or more 300μm or less in FIG. 6 (a) ~ FIG 6 (c). When the width is smaller than 20 μm, the working fluid tends to break due to repetition of freezing and melting. There is a possibility that smooth communication of the working fluid is hindered.

For Ekiren communication opening portion 14c, the size of the opening along the liquid flow path grooves 14a shown extend at C ₃ in Figure 5 is preferably 20μm or more 180μm or less.
Further, it is preferable that the pitch of Ekiren communication opening portion 14c adjacent in the extending direction the liquid flow path groove 14a shown in _{C 4} in FIG. 5 is 300μm or more 2700μm or less.

  In this embodiment, the cross-sectional shape of the liquid channel groove 14a is a semi-elliptical shape, but is not limited to this, but is not limited to a square such as a square, a rectangle, or a trapezoid, a triangle, a semi-circle, a semi-circular bottom, and a semi-elliptical bottom. And so on.

  Further, it is preferable that the liquid passage groove 14a is formed continuously along the edge in the closed space. That is, it is preferable that the liquid passage groove 14a extends annularly over one circumference without being cut by another component. This reduces the factor that hinders the movement of the condensate, so that the condensate can be moved smoothly.

  Returning to FIG. 2 and FIG. 3, the inner liquid flow path 15 will be described. The inner liquid flow path 15 also functions as a liquid flow path, and is a part of the condensed liquid flow path 3 that passes when the working fluid is condensed and liquefied. FIG. 8A shows the portion indicated by VIIIa in FIG. This figure also shows the cross-sectional shape of the inner liquid flow path 15. FIG. 8B is an enlarged view of the inner liquid flow path portion 15 viewed from the direction indicated by the arrow VIIIb in FIG.

As can be seen from these figures, the inner liquid flow path 15 is formed on the inner surface 10a of the main body 11 inside the ring of the outer liquid flow path 14 which is annular. As can be seen from FIGS. 2A and 2B, the inner liquid flow path portion 15 of the present embodiment is a straight ridge extending in a direction (x direction) parallel to a long side in a rectangular shape of the main body 11 in plan view. A plurality of (three in the present embodiment) inner liquid flow path portions 15 are arranged at intervals in a direction (y direction) parallel to the short side, and are arranged between the vapor flow groove 16. I have.
Each inner liquid flow path section 15 is formed with a liquid flow path groove 15a which is a linear groove parallel to the direction in which the inner liquid flow path section 15 extends. The grooves 15a are arranged at predetermined intervals in a direction different from the extending direction. Accordingly, as can be seen from FIGS. 3 and 8 (a), in the inner liquid flow path portion 15, the liquid flow groove 15a which is a concave portion and the wall 15b which is a convex portion between the liquid flow groove 15a in its cross section are uneven. Are formed repeatedly.
Here, since the liquid passage groove 15a is a groove, the liquid passage groove 15a has a bottom portion and an opening formed on the opposite side facing the bottom portion in the cross-sectional shape.

  By providing the plurality of liquid flow grooves 15a in this manner, the depth and width of each liquid flow groove 15a are reduced, and the cross-sectional area of the condensate liquid flow path 3 (see FIG. 13) is reduced. Large capillary forces can be utilized. On the other hand, by using a plurality of liquid flow grooves 15a, an appropriate internal volume of the condensed liquid flow path 3 as a whole is secured, and a required amount of condensed liquid can be flowed.

  8B, the adjacent liquid passage grooves 15a are formed on the wall 15b in the same manner as in FIG. They communicate with each other through a liquid communication opening 15c provided with an interval. This promotes equalization of the amount of condensed liquid between the plurality of liquid flow grooves 15a, and allows the condensed liquid to flow efficiently. In addition, a liquid communication opening 15 c provided in the wall 15 b adjacent to the steam flow channel groove 16 that forms the steam flow channel 4 connects the steam flow channel 4 and the condensate flow channel 3. Therefore, by forming the liquid communication opening 15c as described later, the condensed liquid generated in the vapor flow path 4 can be smoothly moved to the condensed liquid flow path 3 and generated in the condensed liquid flow path. The steam can also be smoothly moved to the steam flow path 4, which can promote a smooth flow of the working fluid without hindering self-excited oscillation of the working fluid.

6A to 6C, the width of the inner liquid flow path portion 15 at the end where the liquid communication opening 15c is formed is smaller than the width of the wall 15b. It may be formed so as to be smaller than large.
This facilitates the movement of the working fluid through the liquid communication opening 15c.

7, the liquid communication openings 15c are provided at different positions in the direction in which the liquid flow grooves 15a extend across the one liquid flow groove 15a, following the example of FIG. It may be arranged.
By providing the liquid communication opening 15c offset as described above, the liquid communication opening 15c does not appear on both sides at the same time when viewed from the working fluid traveling through the condensate flow path 3, and the liquid communication opening 15c Appears, there is always a wall 15b on at least one side. Therefore, the capillary force can be continuously obtained. By forming the liquid communication opening 15c offset from this viewpoint, the capillary force acting on the working fluid can be kept high, so that the working fluid can move more smoothly.
Also, in the case where the liquid communication openings 15c are arranged in an offset manner as described above, the end shape of the wall 15b can be configured in accordance with the examples of FIGS. 6 (a) to 6 (c).

It is preferable that the inner liquid flow path unit 15 having the above configuration further has the following configuration.
FIG. 2 (b), the width of 3, the inner liquid channel section 15 shown in _{E 10} in FIG. 8 is preferably 100μm or 2000μm or less. Further, the pitch of the plurality of inner liquid flow paths 15 is preferably 200 μm or more and 4000 μm or less. This makes it possible to sufficiently reduce the flow path resistance of the steam flow path, and achieve a good balance between the self-excited vibration of the working fluid in the steam flow path and the movement of the working fluid by the action of the capillary force in the condensate flow path.

For liquid flow path grooves 15a, FIG. 8 (a), the it is preferred that the groove width shown in _{F 1} in FIG. 8 (b) is 10μm or more 300μm or less.
The depth of the groove indicated by G in FIG. 8A is preferably 5 μm or more and 200 μm or less. Thereby, the capillary force of the condensate flow path necessary for the movement of the condensate can be sufficiently exerted. Here, the groove depth G is preferably smaller than the remaining sheet thickness obtained by subtracting the groove depth G from the thickness of the first sheet 10. This makes it possible to more reliably prevent the sheet from being broken when the working fluid is frozen.
From the viewpoint of more strongly exerting the capillary force of the flow channel, the aspect ratio (aspect ratio) in the flow channel cross section represented by F ₁ / G is preferably larger than 1.0 or smaller than 1.0. . Among them, it is preferable that F ₁ > G from the viewpoint of manufacturing, and the aspect ratio is preferably larger than 1.3.

Also, the walls 15b, FIG. 8 (a), the it is preferable that the width indicated by _{F 2} in FIG. 8 (b) is 20μm or more 300μm or less. When the width is smaller than 20 μm, the working fluid is liable to break due to repeated freezing and melting, and when the width is larger than 300 μm, the width of the liquid communication opening 14 c becomes too large, and the smooth communication between the condensate flow paths 3 is performed. May be hindered.

For Ekiren communication opening 15c, it is preferable the size of the opening along the liquid flow path grooves 15a shown extend at _{F 3} in FIG. 8 (b) is 20μm or more 180μm or less.
Further, it is preferable that the pitch of Ekiren communication opening portion 15c adjacent in the direction in which the liquid flow path groove 15a shown extend at _{F 4} in FIG. 8 (b) is 300μm or more 2700μm or less.

  In the present embodiment, the cross-sectional shape of the liquid channel groove 15a is a semi-elliptical shape, but is not limited thereto, and is not limited to a square, a rectangle, a trapezoid, and the like, a triangle, a semi-circle, a semi-circular bottom, and a semi-elliptical bottom. And so on.

  Next, the steam flow channel 16 will be described. The steam flow channel 16 is a portion where the vapor-like and condensed working fluid self-oscillates and forms a part of the steam flow channel 4. FIG. 2B shows the shape of the steam flow channel 16 in plan view, and FIG. 3 shows the cross-sectional shape of the steam flow channel 16.

As can be seen from these drawings, the steam flow channel 16 is formed by a straight groove formed on the inner surface 10 a of the main body 11 inside the ring of the annular outer liquid flow channel portion 14. Specifically, the vapor flow channel groove 16 of the present embodiment is formed between the adjacent inner liquid flow channel portions 15 and between the outer peripheral liquid flow channel portion 14 and the inner liquid flow channel portion 15. The groove is a rectangle that extends in a direction (x direction) parallel to the long side. A plurality of (four in the present embodiment) steam flow grooves 16 are arranged in a direction (y direction) parallel to the short side. Therefore, as can be seen from FIG. 3, the first sheet 10 is repeatedly provided with irregularities in which the outer liquid passage portion 14 and the inner liquid passage portion 15 are convex and the vapor passage groove 16 is concave in the y direction. It has a different shape.
Here, since the steam passage groove 16 is a groove, it has a bottom portion and an opening formed on the opposite side facing the bottom portion in the cross-sectional shape.

The steam flow channel 16 is configured such that when the steam flow channel 4 is formed in combination with the steam flow channel 26 of the second sheet 20, self-excited oscillation of the working fluid occurs in the steam flow channel 4. Just do it. Therefore, it is preferable that the steam flow channel 16 further has the following configuration.
FIG. 2 (b), the width of the steam flow passage 16 shown in _{H 10} in FIG. 3, the width _{C 1} of at least the above liquid flow path grooves 14a, are formed larger than the width _{F 1} of the liquid flow path grooves 15a, It is preferably from 100 μm to 2000 μm.
On the other hand, the depth of the steam flow passage 16 shown in _{I 10} in FIG. 3, the depth D of at least the above liquid flow path grooves 14a, is larger than the depth G of the liquid flow path grooves 15a, 10 [mu] m or more 300μm The following is preferred.
As a result, a stable self-excited vibration of the working fluid is obtained when the steam flow path is formed, and the flow path cross-sectional area of the steam flow path groove is made larger than that of the liquid flow path groove. In addition, the vapor having a larger volume than the condensate can be smoothly moved.

Here, when the steam flow channel 4 is formed by combining the second sheet 20 with the steam flow channel 4 as described later, the width of the steam flow channel 4 is height (size in the thickness direction). It is preferable to be configured so as to have a larger flat shape. Therefore, the aspect ratio represented by H ₁₀ / I ₁₀ is preferably 4.0 or more, more preferably 8.0 or more.

  In the present embodiment, the cross-sectional shape of the steam passage groove 16 is a semi-elliptical shape, but the shape is not limited to this, but a square such as a square, a rectangle, or a trapezoid, a triangle, a semi-circle, a semi-circular bottom, a semi-elliptical bottom, or the like. You may.

The steam flow passage groove 17 communicates the plurality of steam flow passage grooves 16, and is combined with the steam flow passage communication groove 27 of the second sheet 20 to form the plurality of steam flow passages 4 formed by the steam flow passage grooves 16 at their end portions. Is a groove that forms a flow path that communicates with. Thereby, the self-excited vibration of the working fluid generated in the steam flow path 4 in the direction in which the inner liquid flow path 15 extends can be balanced.
In addition, this makes it possible to equalize the working fluid in the steam flow path 4 or to carry the steam to a wider range, thereby efficiently condensing the liquid flow path 3 by the liquid flow grooves 14a and the liquid flow grooves 15a. It can be used well.

  As can be seen from FIGS. 2A and 2B, the steam flow passage groove 17 of the present embodiment has both ends in the direction in which the inner liquid flow path portion 15 extends and both ends in the direction in which the steam flow groove 16 extends. And the outer peripheral liquid flow path portion 14. FIG. 4B shows a cross section orthogonal to the communication direction of the steam flow passage communication groove 17. In addition, since the boundary between the steam flow path communication groove 17 and the steam flow path 16 is not necessarily formed by the shape, the boundary is shown in FIGS. 2A and 2B for easy understanding. Indicated by a dotted line.

The shape of the steam flow passage groove 17 is not particularly limited as long as the steam flow passage groove 17 can communicate with the adjacent steam flow groove 16, and may have the following configuration, for example.
FIG. 2 (b), the width of the steam channel communicating groove 17 shown in _{J 10} in FIG. 4 (b) is preferably 100μm or 1000μm or less.
Further, the depth of the steam flow path communicating groove 17 shown in _{K 10} Fig. 4 (b), preferably at 10μm or 300μm or less, the same as the depth _{I 10} of the steam flow passage 16 among them Is preferred. This facilitates manufacturing.

  In the present embodiment, the cross-sectional shape of the steam flow passage communication groove 17 is a semi-elliptical shape, but is not limited thereto, and is not limited to a square such as a square, a rectangle, or a trapezoid, a triangle, a semi-circle, a semi-circular bottom, a semi-elliptical bottom, or the like. It may be.

As will be described later, when the vapor chamber 1 is considered in an enclosed space 2 surrounded by the joined portions, that is, in a region where the condensate flow path 3 and the vapor flow path 4 are provided, The shape provided is a symmetrical shape with the axis parallel to the direction in which the condensed liquid flow path 3 formed by the inner liquid flow path section 15 and the inner liquid flow path section 25 extends as the symmetric axis.
Accordingly, for the first sheet 10 as well, the outer peripheral liquid flow path portion 14 and the shape provided inside the first sheet 10 have an axis parallel to the direction in which the liquid flow path groove 15a extends as a symmetric axis (IIb in FIG. 2B). -IIb).

Next, the second sheet 20 will be described. In the present embodiment, the second sheet 20 is also a sheet-like member as a whole. 9A is a perspective view of the second sheet 20 viewed from the inner surface 20a side, and FIG. 9B is a plan view of the second sheet 20 viewed from the inner surface 20a side. FIG. 10 shows a cut surface of the second sheet 20 when cut along XX in FIG. 9B. FIG. 11 shows a cut surface of the second sheet 20 when cut by XI-XI in FIG. 9B.
The second sheet 20 has an inner surface 20a, an outer surface 20b opposite to the inner surface 20a, and a side surface 20c that forms a thickness across the inner surface 20a and the outer surface 20b, and a pattern in which the working fluid moves to the inner surface 20a side. Are formed. As will be described later, the inner space 20a of the second sheet 20 and the inner surface 10a of the first sheet 10 described above are overlapped and joined so as to face each other, so that the closed space 2 is formed.

Such a second sheet 20 includes a main body 21 and an injection section 22. The main body 21 is a sheet-like part that forms a part where the working fluid moves, and in the present embodiment, is a rectangle having a circular arc (so-called R) in plan view.
The injection part 22 is a part for injecting the working fluid into the closed space 2 (see FIG. 12) formed by the first sheet 10 and the second sheet 20. In the present embodiment, one side of the main body 21 which is a rectangle in a plan view is used. The sheet is a quadrangular sheet in plan view that protrudes from the sheet. In the present embodiment, an injection groove 22a is formed in the injection portion 22 of the second sheet 20 on the inner surface 20a side, and communicates from the side surface 20c of the second sheet 20 to the inside of the main body 21 (a portion to be the closed space 2). ing.
The thickness of such a second sheet 20 and the constituent material can be considered in the same manner as the first sheet 10.

  On the inner surface 20a side of the main body 21, a structure for moving the working fluid is formed. Specifically, on the inner surface 20 a side of the main body 21, an outer joint portion 23, an outer liquid passage portion 24, an inner liquid passage portion 25, a steam passage groove 26, and a steam passage communication groove 27 are provided. ing.

The outer peripheral joint 23 is a surface formed on the inner surface 20 a side of the main body 21 along the outer periphery of the main body 21. The outer peripheral joint 23 overlaps the outer peripheral joint 13 of the first sheet 10 and is joined (diffusion joined, brazed, or the like) to form the closed space 2 between the first sheet 10 and the second sheet 20. Then, the working fluid is sealed therein.
FIG. 9 (b), the 10, it is preferable that the width of the outer peripheral joint 23 shown in _{A 20} in FIG. 11 is the same as the width _{A 10} of the outer joint portion 13 of the body 11 described above.

  In the outer peripheral joint 23, holes 23a penetrating in the thickness direction (z direction) are provided at the four corners of the main body 21. The hole 23a functions as a positioning unit when overlapping with the first sheet 10.

  The outer peripheral liquid flow path portion 24 functions as a liquid flow path portion and is a portion that constitutes a part of the condensed liquid flow path 3 (for example, see FIG. 13) that is a flow path that passes when the working fluid is condensed and liquefied. is there.

The outer liquid passage portion 24 is formed along the inner surface of the outer joint portion 23 of the inner surface 20 a of the main body 21, and is formed so as to form an annular shape along the outer periphery of the closed space 2. In the present embodiment, as can be seen from FIGS. 10 and 11, the outer peripheral liquid flow path portion 24 of the second sheet 20 has a flat surface and is flush with the outer peripheral joint portion 23 before being joined to the first sheet 10. As a result, the condensed liquid flow path 3 is formed by closing the opening of at least a part of the liquid flow grooves 14a of the plurality of liquid flow grooves 14a of the first sheet 10 described above. The detailed mode regarding the combination of the first sheet 10 and the second sheet 20 will be described later.
Since the outer peripheral joint portion 23 and the outer peripheral liquid flow path portion 24 are flush with each other in the second sheet 20 in this manner, there is no boundary line that distinguishes the two from each other structurally. However, for the sake of simplicity, in FIG. 9A and FIG. 9B, the boundary between the two is indicated by a dotted line.

It is preferable that the outer liquid passage portion 24 has the following configuration.
FIG. 9 (b), the 10, the width _{B 20} of the outer fluid passage section 24 shown in FIG. 11 is not particularly limited, the same as the width _{B 10} of the outer fluid flow passage portion 14 of the first sheet 10 Or different. In this embodiment are the same as the width _{B 10} and the width _{B 20.}
If the width B ₂₀ less than the width B _10, at least part of the outer circumferential fluid flow path portion 14, the opening of the liquid flow path grooves 14a are opened without being closed by the outer peripheral liquid flow path portion 24, condensed from here Since the liquid easily enters and the steam easily emerges, the working fluid can be moved more smoothly.

  Next, the inner liquid passage 25 will be described. The inner liquid flow path 25 is also a liquid flow path, and is one part of the condensed liquid flow path 3.

As can be seen from FIGS. 9A, 9B, 10 and 11, the inner liquid flow path portion 25 is formed on the inner surface 20 a of the main body 21 by forming an annular ring of the outer liquid flow path portion 24. It is formed inside. The inner liquid flow path portion 25 of the present embodiment is a straight convex ridge extending in a direction parallel to the long side (x direction) of the main body 21 in a plan view, and a plurality (three in the present embodiment) of inner liquid flow sections. The passages 25 are arranged between the steam flow grooves 26 at predetermined intervals in a direction (y direction) parallel to the short side.
In the present embodiment, each inner liquid passage portion 25 is formed such that the surface on the inner surface 20a side becomes a flat surface before joining with the first sheet 10. Thereby, the condensed liquid flow path 3 is formed by closing the opening of at least a part of the liquid flow grooves 15a of the plurality of liquid flow grooves 15a of the first sheet 10 described above.
In the case where the groove for forming the condensed liquid flow path 3 is not formed in the inner liquid flow path section 25 as in the present embodiment, the thickness of the second sheet 20 is set to the liquid flow path groove of the first sheet 10. It is preferably equal to or more than the depth G of 15a (see FIG. 8A). Thereby, it is possible to prevent breakage (tear) on the second sheet side in the vapor chamber.

FIG. 9 (b), the width E ₂₀ of the inner fluid passage section 25 shown in FIG. 10 is not particularly limited, it may be the same as the width E ₁₀ of the inner fluid flow path portion 15 of the first sheet 10 , May be different. In this embodiment are the same as the width _{E 10} and width _{E 20.}
It is possible to reduce the influence of positional deviation at the time of bonding and the width E ₂₀ and width E ₁₀ are different. In the case where the width E ₂₀ smaller than the width E _10, at least a portion of the inner fluid passage 15, the opening of the liquid flow path grooves 15a are opened without being closed by the inner fluid flow path portion 25 Since the condensed liquid can easily enter from here and the generated steam can easily come out, the working fluid can be moved more smoothly.

  Next, the steam flow channel 26 will be described. The steam flow channel groove 26 is a portion where the vapor-like and condensed liquid working fluid self-oscillates, and forms a part of the steam flow channel 4. FIG. 9B shows the shape of the steam flow channel 26 in plan view, and FIG. 10 shows the cross-sectional shape of the steam flow channel 26.

As can be seen from these drawings, the steam flow channel 26 is formed by a straight groove formed on the inner surface 20 a of the main body 21 inside the ring of the annular outer liquid flow path portion 24. Specifically, the vapor flow channel groove 26 of the present embodiment is formed between the adjacent inner liquid flow channel portions 25 and between the outer peripheral liquid flow channel portion 24 and the inner liquid flow channel portion 25. The groove is a rectangle that extends in a direction (x direction) parallel to the long side. A plurality of (four in this embodiment) steam flow grooves 26 are arranged in a direction (y direction) parallel to the short side. Therefore, as can be seen from FIG. 10, the second sheet 20 is formed with a ridge in which the outer liquid passage 24 and the inner liquid passage 25 are convex in the y direction, and the steam passage groove 26 is concave. A concave streak is formed, and a shape in which these irregularities are repeated is provided.
Here, since the steam flow channel 26 is a groove, it has a bottom and an opening formed on the opposite side facing the bottom in the cross-sectional shape.

The steam flow channel 26 is preferably arranged at a position overlapping the steam flow channel 16 of the first sheet 10 in the thickness direction when combined with the first sheet 10. Thereby, the steam passage 4 can be formed by the steam passage groove 16 and the steam passage groove 26.
FIG. 9 (b), the width of the steam flow path groove 26 shown in H ₂₀ 10 is not particularly limited, and may the same as the width H ₁₀ of the steam flow passage 16 of the first sheet 10, It may be different. In this embodiment are the same as the width _{H 10} and width _{H 20.}
When the width H ₂₀ and width H ₁₀ are different, it is possible to reduce the influence of positional deviation at the time of bonding. Note that when increasing the width H ₂₀ than the width H _10, at least a portion of the inner fluid passage 15, the opening of the liquid flow path grooves 15a are opened without being closed by the inner fluid flow path portion 25 Since the condensed liquid can easily enter from here and the vapor can easily be emitted, the working fluid can be moved more smoothly.
On the other hand, the depth of the steam flow path groove 26 shown in _{I 20} in FIG. 10 is preferably 10μm or more 300μm or less.

Here, when the steam passage 4 is formed in combination with the first sheet 10 as described later, the width of the steam passage 4 has a height (a size in a thickness direction). It is preferable to be configured so as to have a larger flat shape. Therefore, the aspect ratio represented by H ₂₀ / I ₂₀ is preferably 4.0 or more, and more preferably 8.0 or more.

  In this embodiment, the cross-sectional shape of the steam flow channel groove 26 is a semi-elliptical shape, but may be a square such as a square, a rectangle, or a trapezoid, a triangle, a semi-circle, a semi-circular bottom, a semi-elliptical bottom, or the like.

  The steam flow path communication groove 27 is a groove that is combined with the steam flow path communication groove 17 of the first sheet 10 to form a flow path that communicates the ends of the plurality of steam flow paths 4 with the steam flow path groove 26. . This makes it possible to balance the self-excited vibration of the working fluid generated in the steam flow path 4 in the direction in which the inner liquid flow path 25 extends. In addition, the working fluid in the steam flow path 4 can be equalized, and the steam can be transported to a wider range, so that many condensate flow paths 3 can be used efficiently. It becomes possible to make it smoother.

  As can be seen from FIG. 9B and FIG. 11, the steam flow passage communication groove 27 of the present embodiment has both ends in the direction in which the inner liquid flow path 25 extends and both ends in the direction in which the steam flow groove 26 extends. It is formed between the outer peripheral liquid flow path portion 24. FIG. 11 shows a cross section orthogonal to the communication direction of the steam flow passage communication groove 27.

FIG. 9 (b), the width of the steam channel communicating groove 27 shown in J ₂₀ 11 is not particularly limited, the same as the width J ₁₀ steam channel communication groove 17 of the first sheet 10 may be, it may be different from the width J _10. Incidentally, when greater than the width J ₁₀ width J ₂₀ is formed at least in part, the opening of the liquid flow path grooves 14a are a part of the steam flow path 4 of the outer circumferential fluid flow path portion 14 of the first sheet 10 As a result, the condensed liquid can easily enter, and the generated vapor can be easily emitted, so that the working fluid can be moved more smoothly.

The size of the width _{J 20} is preferably 1000μm or less the range of 100 [mu] m, the depth of the steam flow path communicating groove 27 shown in _{K 20} 11 is preferably 10μm or more 300μm or less.

  In the present embodiment, the cross-sectional shape of the steam flow passage communication groove 27 is a semi-elliptical shape, but is not limited thereto, and is not limited to a square such as a square, a rectangle, and a trapezoid, a triangle, a semi-circle, a semi-circular bottom, and a semi-elliptical bottom. There may be.

As will be described later, when the vapor chamber 1 is considered in an enclosed space 2 surrounded by the joined portions, that is, in a region where the condensate flow path 3 and the vapor flow path 4 are provided, The shape provided is a symmetrical shape with the axis parallel to the direction in which the condensed liquid flow path 3 formed by the inner liquid flow path section 15 and the inner liquid flow path section 25 extends as the symmetric axis.
Therefore, for the second sheet 20 as well, the outer liquid flow path portion 24 and the inside thereof are provided with a shape in which the axis parallel to the direction in which the inner liquid flow path portion 25 extends is a symmetric axis (FIG. 9B). IXb-IXb).

Next, the structure when the first sheet 10 and the second sheet 20 are combined to form the vapor chamber 1 will be described. From this description, the arrangement, size, shape, and the like of each component of the first sheet 10 and the second sheet 20 are further understood.
FIG. 12 illustrates a cut surface obtained by cutting the vapor chamber 1 in the thickness direction along the y direction indicated by XII-XII in FIG. This drawing is a combination of the drawing shown in FIG. 3 of the first sheet 10 and the drawing shown in FIG. 10 of the second sheet 20, and shows a cut surface of the vapor chamber 1 in this portion.
FIG. 13 is an enlarged view of the portion indicated by XIII in FIG.
FIG. 14 illustrates a cut surface cut in the thickness direction of the vapor chamber 1 along the x direction indicated by XIV-XIV in FIG. This figure is a view in which the view shown in FIG. 4B of the first sheet 10 and the view shown in FIG. 11 of the second sheet 20 are combined to show a cut surface of the vapor chamber 1 at this portion. It is.

  As can be seen from FIGS. 1A, 1B, and 12 to 14, the first sheet 10 and the second sheet 20 are arranged and joined so as to be overlapped to form the vapor chamber 1. ing. At this time, the inner surface 10a of the first sheet 10 and the inner surface 20a of the second sheet 20 are arranged so as to face each other, the main body 11 of the first sheet 10 and the main body 21 of the second sheet overlap, and The injection part 12 and the injection part 22 of the second sheet 20 overlap. In the present embodiment, the relative positional relationship between the first sheet 10 and the second sheet 20 is configured to be appropriate by aligning the positions of the holes 13a of the first sheet 10 and the holes 23a of the second sheet 20. ing.

  With such a laminated body of the first sheet 10 and the second sheet 20, the respective components provided in the main body 11 and the main body 21 are arranged as shown in FIGS. Specifically, it is as follows.

  The outer peripheral joint portion 13 of the first sheet 10 and the outer peripheral joint portion 23 of the second sheet 20 are arranged so as to overlap with each other, and both are joined by joining means such as diffusion joining or brazing. Thereby, the closed space 2 is formed between the first sheet 10 and the second sheet 20.

The effect of the vapor chamber 1 of this embodiment is particularly large when the vapor chamber 1 is thin. Figure 1 From this point of view, the thickness of the vapor chamber 1 shown in FIG. 12 in _{L 0} is 1mm or less, more preferably 0.4mm or less, more preferably 0.2mm or less. By setting the thickness to 0.4 mm or less, in the electronic device in which the vapor chamber 1 is installed, the vapor chamber can be installed inside the electronic device without processing (for example, forming a groove) for forming a space in which the vapor chamber is arranged. Increase. According to this embodiment, even in such a thin vapor chamber, the working fluid can move smoothly.

The outer liquid passage portion 14 of the first sheet 10 and the outer liquid passage portion 24 of the second sheet 20 are arranged so as to overlap. Thus, the condensed liquid flow path 3 through which the condensed liquid in which the working fluid is condensed and liquefied is formed by the liquid flow path groove 14a of the outer liquid flow path 14 and the outer liquid flow path 24.
Similarly, the inner liquid flow path portion 15 that is a ridge of the first sheet 10 and the inner liquid flow path portion 25 that is a ridge of the second sheet 20 are arranged so as to overlap. As a result, the condensed liquid passage 3 through which the condensed liquid flows is formed by the liquid passage groove 15a of the inner liquid passage 15 and the inner liquid passage 25.

Here, it is preferable that the condensate flow path 3 has a flat cross-sectional shape as the vapor chamber 1 becomes thinner. As a result, the capillary force can be increased, and the movement of the condensate can be performed more smoothly, so that the heat transport capability can be maintained at a high level. More specifically, the ratio represented by the width / height of the condensate flow path 3 is preferably greater than 1.0 and not more than 4.0.
The width of the condensate flow path 3, in the present embodiment is analogous to the width _{F 1} of Ekiryuromizo 15a, is preferably 10μm or more 300μm or less. If the width is smaller than 10 μm, the flow path resistance increases, and the transport capacity may be reduced. On the other hand, when the width is larger than 300 μm, the capillary force is reduced, and the transport capacity may be reduced.
In this embodiment, the height of the condensed liquid flow path 3 is in accordance with the depth G of the liquid flow path groove 15a, but is preferably 5 μm or more and 200 μm or less. Thereby, the capillary force of the condensate flow path necessary for the movement can be sufficiently exerted. The height is preferably equal to or less than the thickness (thickness) of the first sheet 10 and the second sheet 20 on one side and the other side in the thickness direction (z direction) across the condensate flow path 3. . Thereby, breakage (breakage) of the vapor chamber caused by the condensate flow path 3 can be further prevented.

  In this embodiment, since the liquid flow channel 14a and the liquid flow channel 15a are provided only in the first sheet 10, the height of the condensed liquid flow channel is the depth of the liquid flow channel 14a and the liquid flow channel 15a. However, the present invention is not limited thereto, and the second sheet 20 may be provided with a liquid channel groove. In this case, the condensate flow path is formed by overlapping the liquid flow path groove of the first sheet and the liquid flow path groove of the second sheet, and the condensate liquid according to the total depth of both liquid flow path grooves is formed. It is the height of the channel.

  Further, as described above, the liquid communication opening 14c and the liquid communication opening 15c are formed in the condensed liquid flow path 3. As a result, the plurality of condensed liquid passages 3 communicate with each other, the condensed liquid is equalized, and the condensed liquid is efficiently moved. The liquid communication openings 14c and the liquid communication openings 15c adjacent to the vapor flow path 4 and communicating the vapor flow path 4 and the condensate liquid flow path 3 smoothly condense the condensate generated in the vapor flow path 4. The working fluid can be moved to the liquid flow path 3 and the steam generated in the condensed liquid flow path 3 can be smoothly moved to the vapor flow path 4 to move the working fluid quickly.

  In addition, it is preferable that the condensed liquid flow path 3 formed by the outer peripheral liquid flow path section 14 and the outer peripheral liquid flow path section 24 is formed in an annular shape continuously along the edge in the closed space 2. In other words, the condensed liquid flow path 3 formed by the outer liquid flow path section 14 and the outer liquid flow path section 24 may extend in an annular shape over one circumference without being cut by other components. preferable. As a result, factors that hinder the movement of the condensed liquid can be reduced, and the condensed liquid can be smoothly moved.

The opening of the steam passage groove 16 of the first sheet 10 and the opening of the steam passage groove 26 of the second sheet 20 overlap so as to face each other to form a passage, and this is the steam passage 4 in which the working fluid self-oscillates. Becomes
Here, it is preferable that the cross-sectional shape of the steam flow path 4 be flat as the vapor chamber 1 becomes thinner. As a result, even if the thickness is reduced, the surface area in the flow path can be secured, and the heat transport capability can be maintained at a high level. More specifically, the width _{W B} of the steam flow path 4 shown in FIG. 13, the height _{H B,} it is preferable ratio represented by W B / _{H B} is 2.0 or more. From the viewpoint of ensuring a higher heat transport capability, the ratio is more preferably equal to or greater than 4.0.

  As can be seen from FIG. 14, an overlapping flow path is formed so that the opening of the steam flow path communication groove 17 of the first sheet 10 and the opening of the steam flow path communication groove 27 of the second sheet 20 face each other. The plurality of steam flow paths 4 formed by the groove 16 and the steam flow path groove 26 are communicated at their ends to form a flow path for balancing the self-excited vibration of the working fluid.

  Due to the above-described condensate flow path 3 and vapor flow path 4, the vapor chamber 1 has a shape in which a plurality of linear condensate flow paths 3 are arranged between two vapor flow paths 4. . As a result, the condensate flow path 3 through which the condensate mainly flows and the vapor flow path 4 in which the vapor mainly self-oscillates are separated and alternately arranged, and the smooth movement of the working fluid is assisted. .

  Due to the steam flow path 4 and the condensate flow path 3 in the closed space 2, the working fluid vibrates in the steam flow path 4 by self-excited vibration, so that heat is efficiently transferred and diffused. On the other hand, since the condensed liquid moves efficiently by the capillary force by the condensed liquid flow path 3 provided separately from the vapor flow path 4, the occurrence of dryout can be suppressed.

As also shown in FIG. 1, the inner surface 10 a and the inner surface 20 a of the injection part 12 and the injection part 22 are overlapped so that they face each other, and the opening on the side opposite to the bottom of the injection groove 22 a of the second sheet 20 is the first. An injection channel 5 is formed, which is closed from the inner surface 10a of the injection portion 12 of the sheet 10 and communicates the outside with the sealed space 2 (condensate flow channel 3 and vapor flow channel 4) between the main body 11 and 21. .
However, after the working fluid is injected from the injection channel 5 into the closed space 2, the injection channel 5 is closed, so that the outside and the closed space 2 communicate with each other in the final form of the vapor chamber 1. Absent.

  A working fluid is sealed in the closed space 2 of the vapor chamber 1. Although the type of the working fluid is not particularly limited, a working fluid used in a normal vapor chamber, such as pure water, ethanol, methanol, or acetone, can be used.

It is preferable that the above-described vapor chamber 1 further has the following configuration. FIG. 15 shows a diagram for explanation. FIG. 15 is a view showing the inside of the vapor chamber 1 in a see-through manner, and the closed space 2 (that is, the area in which the vapor flow path and the condensate flow path are formed) is shown by a solid line.
When considering the inside of the sealed space 2 surrounded by the joined portions, that is, the inside of the region where the condensate flow path 3 and the vapor flow path 4 are provided, the vapor chamber 1 has the inner liquid The symmetrical shape (XV-XV in FIG. 15) is set as an axis parallel to the direction in which the condensed liquid flow path 3 formed by the flow path section 15 and the inner liquid flow path section 25 extends.

Thereby, the balance of the self-excited vibration is maintained during the operation of the vapor chamber, and the vibration is stably generated, so that the high heat transfer capability can be exhibited with high reliability. On the other hand, when the vapor chamber is not operating, the condensate is dispersed throughout the vapor chamber and is prevented from concentrating at one location, so that even if the working fluid freezes and expands, the vapor chamber is destroyed. Can be prevented.
Therefore, even if the working fluid is used in an environment where the working fluid freezes, the thickness, the heat transport ability, and the durability are all satisfied.

The above vapor chamber can be manufactured, for example, as follows.
The liquid flow grooves 14a, the liquid flow grooves 15a, the steam flow grooves 16, the steam flow grooves 26, and the steam flow passage grooves 17 are formed on the metal sheet having the outer peripheral shape of the first sheet 10 and the second sheet 20. The steam flow passage groove 27 is formed by half etching. Here, the half-etching refers to forming a groove or a dent by removing a material by etching halfway in the thickness direction without penetrating the thickness direction by etching.

Next, the inner surface 10a and the inner surface 20a of the first sheet 10 and the second sheet 20 are overlapped so as to face each other, are positioned using the holes 13a and 23a as positioning means, and are temporarily fixed. The method of temporary fixing is not particularly limited, and examples thereof include resistance welding, ultrasonic welding, and bonding with an adhesive.
Then, diffusion bonding is performed after the temporary fixing, and the first sheet 10 and the second sheet 20 are permanently bonded. In addition, you may join by brazing instead of diffusion joining.

  After the joining, a vacuum is drawn from the injection channel 5 formed, and the pressure in the closed space 2 is reduced. Thereafter, a working fluid is injected from the injection flow path 5 into the depressurized closed space 2, and the working fluid is introduced into the closed space 2. Then, the injection flow path 5 is closed by using or caulking the injection part 12 and the injection part 22 by laser melting. Thus, the working fluid is stably held inside the closed space 2.

  Next, the operation when the vapor chamber 1 operates will be described. FIG. 16 schematically shows a state in which the vapor chamber 1 is arranged inside a portable terminal 40 which is one form of the electronic device. Here, the vapor chamber 1 is indicated by a dotted line because it is disposed inside the housing 41 of the portable terminal 40. Such a portable terminal 40 includes a housing 41 containing various electronic components, and a display unit 42 exposed so that an image can be seen outside through an opening of the housing 41. The electronic component 30 to be cooled by the vapor chamber 1 as one of these electronic components is arranged in the housing 41.

The vapor chamber 1 is installed in a housing of a portable terminal or the like, and is attached to an electronic component 30 such as a CPU which is an object to be cooled. The electronic component 30 is attached directly to the outer surface 10b or the outer surface 20b of the vapor chamber 1 or via an adhesive, a sheet, a tape, or the like having high thermal conductivity.
Here, when the vapor chamber 1 is viewed in a plan view from among the outer surface 10b and the outer surface 20b of the vapor chamber 1, the electronic component 30 is overlapped with any one of the symmetry axes XV-XV shown in FIG. Is preferably mounted so that is arranged. More preferably, at this time, the electronic components 30 are also arranged so that XV-XV is the axis of symmetry (see FIG. 17). Thereby, the steam flow path 4 is symmetrical with respect to the position of the heat source, and the balance of the self-excited vibration is maintained during the operation of the vapor chamber, and the vibration is stabilized, so that a high heat transfer capability can be exhibited.

FIG. 17 is a diagram illustrating the behavior of the working fluid. For ease of explanation, the second sheet 20 is omitted in this figure, and the inner surface 10a of the first sheet 10 is shown so as to be visible.
When the electronic component 30 generates heat, the heat is transmitted through the first sheet 10 by heat conduction, and the condensed liquid existing at a position close to the electronic component 30 in the closed space 2 receives the heat. The condensate that has received the heat absorbs the heat, evaporates and evaporates. Thereby, the electronic component 30 is cooled.

  The vaporized working fluid turns into steam, generates self-excited vibration in the steam flow path 4, and moves so as to vibrate in the steam flow path 4 as shown by a solid straight arrow in FIG. More specifically, the working fluid moves so as to vibrate in the steam flow channel 4 formed by the inner flow channel portion 15, the steam flow channel 16, which is parallel to the direction in which the inner flow channel portion 25 extends, and the steam flow channel 26. I do. During the movement, the first sheet 10 and the second sheet 20 are cooled while depriving heat. The first sheet 10 and the second sheet 20, which have taken heat from the steam, transfer the heat to the outer surface 10b, the housing of the portable terminal device which has come into contact with the outer surface 20b, and finally the heat is released to the outside air. Then, the working fluid deprived of heat while moving in the steam flow path 4 is condensed and liquefied. Therefore, the condensed liquid also exists in the steam flow path 4, and the self-excited vibration is performed in a state where the steam and the condensed liquid are alternately present in the steam flow path 4.

  Part of the condensate generated in the vapor flow path 4 moves to the condensate flow path 3 from the liquid communication opening or the like. Since the condensed liquid flow path 3 of the present embodiment includes the liquid communication opening 14c and the liquid communication opening 15c, the condensed liquid passes through the liquid communication opening 14c and the liquid communication opening 15c and a plurality of condensed liquid flow paths. It is distributed to three.

  The condensed liquid that has entered the condensed liquid flow path 3 moves toward the electronic component 30 that is a heat source as indicated by a dotted straight arrow in FIG. 17 due to the capillary force generated by the condensed liquid flow path. Then, it is vaporized again by the heat from the electronic component 30 as a heat source, and the above operation is repeated.

  As described above, according to the vapor chamber 1, the working fluid can be moved smoothly and favorably by the self-excited vibration in the vapor flow path and the high capillary force in the condensate flow path, and the heat transfer amount can be increased. Can be. At this time, since each channel has a structure symmetrical with respect to the axis of symmetry XV-XV, the balance of the self-excited vibration is maintained when the vapor chamber is operated, and the self-excited vibration is stabilized. The transportation capacity can be more reliably demonstrated.

  FIG. 18 is a diagram illustrating a vapor chamber 101 according to the second embodiment. FIG. 18A illustrates a view of the second sheet 120 viewed from the inner surface 20a side. FIG. 18B is a perspective view of the inside of the vapor chamber 101 in which the first sheet 10 and the second sheet 120 are combined, as in FIG. 15, and shows the closed space 102 (that is, the steam flow path and the condensate flow). FIG. 3 is a diagram showing a region where a road is formed) by a solid line.

  In the vapor chamber 101, a groove 122a is formed in the outer peripheral liquid flow path portion 24 of the second sheet 120, at a position just opposite to a position where the injection groove 22a is provided. The shape of the groove 122a is the same as that of the portion where the injection groove 22a intersects the outer peripheral liquid flow path portion 24.

Thus, like the vapor chamber 1, the vapor chamber 101 is considered within the closed space 102 surrounded by the joined portions, that is, within the area where the condensate flow path 3 and the vapor flow path 4 are provided. When the condensed liquid flow path 3 formed by the inner liquid flow path section 15 and the inner liquid flow path section 25 is extended in a direction parallel to the direction in which the condensed liquid flow path 3 extends, the shape provided is the symmetric axis (XV in FIG. 18B). -XV).
In addition to this, the vapor chamber 101 is provided when considering the inside of the closed space 102 surrounded by the joined parts, that is, the area where the condensate flow path 3 and the vapor flow path 4 are provided. The shape to be formed is symmetric with the axis perpendicular to the direction in which the condensed liquid flow path 3 formed by the inner liquid flow path 15 and the inner liquid flow path 25 extends as the symmetric axis (XVIII-XVIII in FIG. 18B). It is also shaped.

Thereby, in addition to the effect described in the vapor chamber 1, the symmetry in the structure of the flow path provided in the closed space 102 of the vapor chamber 101 is further increased, and the dispersibility of the condensate when the vapor chamber is not operated is improved. As a result, it is possible to prevent the vapor chamber from breaking even if the working fluid freezes and expands.
Therefore, even if the working fluid is used in an environment where the working fluid freezes, the thickness, the heat transport ability, and the durability are all satisfied.

  FIG. 19 is a diagram illustrating a modified example 101 ′ of the vapor chamber 101 of the second embodiment. FIG. 19A illustrates a view of the second sheet 120 ′ as viewed from the inner surface 20 a side. FIG. 19B is a perspective view of the inside of the vapor chamber 101 ′ in which the first sheet 110 and the second sheet 120 ′ are combined, as in FIG. FIG. 3 is a diagram showing a region where a flow path and a condensate flow path are formed) by a solid line.

  In the vapor chamber 101 ', an injection part 12 of the first sheet 110 and an injection part 22 of the second sheet 120' forming the injection flow path 5 are provided at two places. Specifically, such injection portions 12 and 22 are provided so as to be located at exactly opposite positions (in this embodiment, at both ends in the x direction).

  As a result, in the vapor chamber 101 ′, similarly to the above-described vapor chamber 101, the structure in the closed space is symmetrical with respect to the symmetry axes XV-XV and XVIII-XVIII, so that the symmetry is enhanced, and the vapor chamber 101 is also increased. The same effect is obtained. However, in this example, after the working fluid is sealed in the closed space 2, both the injection channels 5 need to be closed.

  FIG. 20 shows a diagram for explaining the vapor chamber 201 of the third embodiment. FIG. 20A is a perspective view showing the inside of a vapor chamber 201 in which the first sheet 210 and the second sheet 220 are combined, and the closed space 202 (that is, the vapor passage and the condensate passage are formed). FIG. 4 is a diagram showing a (region) by a solid line. FIG. 20B is an enlarged view of a part of the cross section taken along XXb-XXb shown in FIG.

In the vapor chamber 201, pillar projections 218 are arranged at the bottom of the steam flow channel 16 of the first sheet 210, and pillar projections 228 are arranged at the bottom of the steam flow channel 26 of the second sheet 220. A plurality of pillar projections 218 and 228 are arranged at intervals in the direction in which the steam flow grooves 16 and 26 extend, and in this embodiment, the planar shape (the shape from the viewpoint of FIG. 20A) is elliptical. It is.
When the first sheet 210 and the second sheet 220 having such column projections 218 and 228 are overlapped and joined to form the vapor chamber 201, as shown in FIG. The pillar projections 228 are also joined to form one pillar. As a result, this pillar functions as a pillar that supports the steam flow path 4 in the height direction, and it is possible to prevent the vapor chamber from being broken or deformed during manufacturing, use, freezing, and the like.

In the present embodiment, the columnar projections 218 and 228 have an elliptical shape in plan view, but are not limited thereto, and may have other shapes such as a circle, a triangle, a square, other polygons, and wings. Can also. Such a shape can be designed from the viewpoint of low flow resistance and ease of fabrication.
In the present embodiment, the sizes of the upper and lower pillar projections are the same, but may be different. When the sizes are different, it is possible to reduce the influence of positional deviation at the time of joining.
Further, in the present embodiment, a plurality of pillar projections are arranged at an interval with respect to one steam flow channel groove, but may be one continuous pillar ridge.

  FIG. 21 is a diagram illustrating a vapor chamber 301 according to the fourth embodiment. FIG. 21 is a perspective view of the inside of a vapor chamber 301 in which a first sheet 310 and a second sheet 320 are combined, and shows a closed space 302 (that is, a region where a vapor passage and a condensate passage are formed). It is the figure shown by the solid line.

In the vapor chamber 301 of the present embodiment, the inner liquid flow path 15 ′ and the inner liquid flow path 25 ′ provided at the center are longer in the longitudinal direction than the other inner liquid flow paths 15 and the inner liquid flow path 25. It extends, and both ends reach the outer peripheral liquid flow path part 14 and the outer peripheral liquid flow path part 24. Thereby, as can be seen from FIG. 21, in the vapor chamber 4, two flow paths 4 _{L <} b> 1 in which both ends shown by a thick dotted line communicate with each other are formed in the vapor flow path 4. According to such an embodiment, the working fluid can self-excitedly oscillate in the steam flow path 4 to increase the heat transport capability.

  FIGS. 22 to 29 are diagrams illustrating a vapor chamber 401 of the fifth embodiment. FIG. 22 is an external perspective view of the vapor chamber 401, and FIG. 23 is an exploded perspective view of the vapor chamber 401.

  The vapor chamber 401 has a first sheet 410, a second sheet 420, and a third sheet 430 as can be seen from FIGS. The first sheet 410, the second sheet 420, and the third sheet 430 are overlapped and joined (diffusion bonding, brazing, etc.), so that the first sheet 410 and the second sheet 420 Thus, a sealed space 402 surrounded by the first sheet 410, the second sheet 420, and the third sheet 430 is formed (see FIG. 27), and the working fluid is sealed in the sealed space 402.

  In the present embodiment, the first sheet 410 is a sheet-like member as a whole. The first sheet 410 has a flat surface on both sides, and includes an inner surface 410a, an outer surface 410b opposite to the inner surface 410a, and a side surface 410c that forms a thickness across the inner surface 410a and the outer surface 410b. Prepare.

The first sheet 410 includes a main body 411 and an injection section 412. The main body 411 is a sheet-like portion that forms a closed space in which the working fluid moves, and in the present embodiment, is a rectangle having a circular arc (so-called R) in plan view.
The injection part 412 is a part for injecting the working fluid into the closed space formed by the first sheet 410, the second sheet 420, and the third sheet 430. In the present embodiment, one side of the main body 411 that is a rectangle in a plan view is used. The sheet is a quadrangular sheet in plan view that protrudes from the sheet. In the present embodiment, the injection portion 412 of the first sheet 410 has a flat surface on both the inner surface 410a and the outer surface 410b.

The material forming the first sheet 410 is not particularly limited, but may be a single material, or a composite material (a rolled bonding material called a “cladding material”) in which a plurality of different materials are laminated. Or a material laminated by plating).
In the case of a single material, it is preferable that the metal be a metal having a high thermal conductivity. This includes, for example, copper and copper alloy. In particular, by using copper and a copper alloy, it becomes easy to produce a vapor chamber by etching and diffusion bonding while improving the heat transport ability.
In the case of a composite material, for example, a material having a high thermal conductivity on the inner surface 410a side and not reacting to the working fluid, and a material having a high strength on the outer surface 410b side can be used. This includes, for example, a composite material in which the inner surface is copper and the outer surface is stainless steel, or a composite material in which the inner surface is copper and the outer surface is a copper alloy. According to this, it is possible to secure strength such as deformation and destruction while maintaining high thermal performance.

In the present embodiment, the second sheet 420 is a sheet-like member as a whole. The second sheet 420 has a flat surface on both sides, and includes an inner surface 420a, an outer surface 420b opposite to the inner surface 420a, and a side surface 420c that forms a thickness across the inner surface 420a and the outer surface 420b. Prepare. The second sheet 420 also has a main body 421 and an injection section 422.
The second sheet 420 can be considered in the same manner as the first sheet 410. However, the first sheet 410 and the second sheet 420 do not necessarily have to be the same material and the same form, and may be configured to be different.

  In the present embodiment, the third sheet 430 is a sheet that is sandwiched and stacked between the first sheet 410 and the second sheet 420, and has a structure for moving the working fluid in the main body 431. FIG. 24 shows a plan view of the third sheet 430. FIG. 24A is a diagram of a surface superimposed on the second sheet 420, and FIG. 24B is a diagram of a surface superimposed on the first sheet 410. FIG. 25 shows a cut surface along the line XXV-XXV in FIG. 24 (a), and FIG. 26 shows a cut surface along the line XXVI-XXVI in FIG. 24 (a). .

The third sheet 430 includes a main body 431 and an injection section 432. The main body 431 is a sheet-like portion that forms a closed space in which the working fluid moves, and in the present embodiment, is a rectangle whose corners are arcs (so-called R) in plan view.
The injection part 432 is a part that injects the working fluid into the closed space formed by the first sheet 410, the second sheet 420, and the third sheet 430. In the present embodiment, one side of the main body 431 that is a rectangular shape in a plan view is used. The sheet is a quadrangular sheet in plan view that protrudes from the sheet. The injection section 432 has an injection groove 432a formed on the side overlapping the first sheet 410. The injection groove 432a can be considered in the same manner as the above-described injection groove 22a.

  The main body 431 is provided with an outer joint 433, an outer liquid passage 434, an inner liquid passage 435, a vapor passage slit 436, and a vapor passage communication groove 437.

The outer peripheral joint 433 is a portion formed along the outer periphery of the main body 431. Then, one surface of the outer peripheral joint portion 433 overlaps the surface of the first sheet 410 and is joined (diffusion bonding, brazing, etc.), and the other surface overlaps the surface of the second sheet 420 and is joined (diffusion bonding, brazing). Attached, etc.). Thus, a closed space 402 surrounded by the first sheet 410, the second sheet 420, and the third sheet 430 is formed, and the working fluid is sealed therein.
The outer peripheral joint 433 can be considered in the same manner as the outer peripheral joint 13 described above.

  Holes 433a that penetrate in the thickness direction (z direction) are provided at the four corners of the main body 431 in the outer peripheral joint portion 433 of the main body 431. The holes 433a function as positioning means when overlapping the first sheet 410 and the second sheet 420.

The outer peripheral liquid flow path 434 is a part that functions as a liquid flow path and constitutes a part of the condensed liquid flow path 3 that is a flow path that passes when the working fluid is condensed and liquefied. The outer peripheral liquid flow path portion 434 is formed along the inner side of the outer peripheral joint portion 433 of the main body 431, and is provided so as to be annular along the outer periphery of the closed space 402. A liquid flow channel groove 434a is formed on the surface of the outer liquid flow channel portion 434 facing the second sheet 420.
The outer liquid passage 434 and the liquid passage groove 434a provided therein can be considered in the same manner as the outer liquid passage 14 and the liquid passage 14a described above.

  The inner liquid passage 435 also functions as a liquid passage, and is a part of the condensed liquid passage 3 that passes when the working fluid is condensed and liquefied. The inner liquid flow path portion 435 is formed inside the ring of the outer peripheral liquid flow path portion 434 that is annular in the main body 431. The inner liquid flow path portion 435 of the present embodiment is a rod-shaped portion that is a rectangle in a plan view of the main body 431 and extends straight in a direction (x direction) parallel to the long side, and includes a plurality (three in the present embodiment) of inner liquid flow sections. The path portions 435 are arranged at intervals in a direction (y direction) parallel to the short side, and are disposed between the steam flow path slits 436.

  A liquid channel groove 435a, which is a linear groove parallel to the direction in which the inner liquid channel section 435 extends, is formed on the surface of the inner liquid channel section 435 facing the second sheet 420. . The inner liquid channel portion 435 and the liquid channel groove 435a can be considered in the same manner as the inner liquid channel portion 15 and the liquid channel groove 15a described above.

The steam flow path slit 436 is a part of the steam flow path 4 where the steam-like and condensed liquid working fluid self-oscillates. The vapor flow path slit 436 is constituted by a straight slit formed in the main body 431 inside the ring of the outer peripheral liquid flow path portion 434 that is circular. Specifically, the vapor flow path slit 436 of the present embodiment is formed between the adjacent inner liquid flow paths 435 and between the outer liquid flow path 434 and the inner liquid flow paths 435, and the main body 431 is viewed in plan. The slit is a rectangle that extends in a direction (x direction) parallel to the long side. Therefore, the steam flow passage slit 436 penetrates the third sheet 430 in the thickness direction (z direction).
A plurality of (four in this embodiment) steam flow channel slits 436 are arranged in a direction (y direction) parallel to the short side. Therefore, as can be seen from FIG. 25, the third sheet 430 has a shape in which the outer liquid passage 434, the inner liquid passage 435, and the vapor passage slit 436 are alternately repeated in the y direction.

  Such a steam passage slit 436 can be considered in the same manner as the above-described embodiment of the steam passage 4 formed by combining the steam passage groove 16 and the steam passage groove 26.

  In the present embodiment, the cross-sectional shape of the steam passage slit 436 is a shape formed by overlapping part of the elliptical arcs, and the center in the thickness direction protrudes. Other forms such as a quadrangle such as a trapezoid, a triangle, a semicircle, and the like may be used.

The steam flow path communication groove 437 is a groove that forms a flow path that connects the plurality of steam flow path slits 436. This makes it possible to balance the self-excited vibration of the working fluid generated in the steam flow path in the direction in which the inner liquid flow path 435 extends.
In addition, this makes it possible to equalize the working fluid in the steam flow path, to carry the steam to a wider range, and to efficiently use the condensed liquid flow path by the many liquid flow grooves 434a and 435a. I do.

  In the present embodiment, the plurality of inner liquid flow paths 435 are connected by the vapor flow path communication groove 437, and are connected to the outer liquid flow path 434. Thereby, the third sheet 430 is integrated. However, the means for integrating the third sheet 430 in this way is not limited to this, and other means may be used. For example, a piece that is arranged to cross the vapor flow path slit 436, connects the inner liquid flow path 435, and connects this to the outer liquid flow path 434 may be separately provided.

The vapor passage communication groove 437 of the present embodiment is formed between both ends in the direction in which the inner liquid passage 435 extends and both ends in the direction in which the vapor passage slit 436 extends, and the outer periphery liquid passage 434. I have. The shape of the steam flow passage communication groove 437 is not particularly limited as long as the adjacent steam flow passage slits 436 can be communicated, and the shape thereof is not particularly limited. Can be considered in the same manner as a flow path formed by superimposing.
In this embodiment, a hole 437a is provided in a part of the steam flow passage communication groove 437 so as not to block the injection groove 432a.

  The feature of the symmetry of the shape formed in the closed space 402 of the vapor chamber 401 by the configuration of the third sheet 430 described above can be considered in the same manner as in the above-described embodiments of the vapor chambers.

  Such a third sheet 430 can be manufactured by etching performed separately for both surfaces, simultaneous etching from both surfaces, pressing, cutting, or the like.

  FIGS. 27 to 29 show diagrams describing the structure when the first sheet 410, the second sheet 420, and the third sheet 430 are combined to form the vapor chamber 401. FIG. 27 is a sectional view taken along the line XXVII-XXVII in FIG. 22, and FIG. 28 is an enlarged view of a part of FIG. FIG. 29 shows a cut surface along a line indicated by XXIX-XXIX in FIG.

  As can be seen from FIG. 22 and FIGS. 27 to 29, the first sheet 410, the second sheet 420, and the third sheet 430 are arranged and joined so as to overlap each other to form the vapor chamber 401. . At this time, the second sheet is arranged such that the inner surface 410a of the first sheet 410 and one surface of the third sheet 430 (the surface on the side where the liquid flow grooves 434a and 435a are not disposed) face each other. The inner surface 420a of the second sheet 420 and the other surface of the third sheet 430 (the surface on the side where the liquid flow grooves 434a and 435a are arranged) face each other. Similarly, the injection portions 412, 422, and 432 of each sheet are also overlapped.

  Thereby, a closed space 402 surrounded by the first sheet 410, the second sheet 420, and the third sheet 430 is formed between the first sheet 410 and the second sheet 420. In this case, a condensate flow path 3 and a vapor flow path 4 are formed. With respect to the form of the condensate flow path 3 and the vapor flow path 4 in the closed space 402, the same concept as in the above-described vapor chamber can be applied.

1, 101, 201, 301, 401 Vapor chamber 2, 102, 202, 302, 402 Sealed space 3 Condensate flow path 4 Steam flow path 10, 110, 210, 310, 410 First sheet 10a Inner surface 10b Outer surface 10c Side surface 11 , Main body 12 Injection part 13 Outer peripheral joint part 14 Outer peripheral liquid flow path part 14a Liquid flow path groove 14c Liquid communication opening part 15 Inner liquid flow path part 15a Liquid flow path groove 15c Liquid communication opening part 16 Steam flow path groove 17 Steam flow path Communication groove 20, 120, 220, 320, 420 Second sheet 20a Inner surface 20b Outer surface 20c Side surface 21 Main body 22 Injecting portion 23 Outer peripheral joining portion 24 Outer peripheral liquid passage portion 25 Inner liquid passage portion 26 Steam passage groove 27 Steam passage Communication groove 430 Third sheet 436 Steam passage slit

Claims (7)

A sealed chamber is formed between the plurality of sheets, and a vapor chamber in which a working fluid is sealed in the sealed space,
In the closed space, a condensed liquid flow path, which is a flow path in which the working fluid moves in a condensed liquid state, and a flow path cross-sectional area larger than the condensed liquid flow path, and the working fluid is in a state of vapor and condensed liquid. And a steam flow path that self-oscillates at
The condensate flow path has a plurality of linear condensate flow paths arranged between two vapor flow paths,
The plurality of steam channels are in communication,
The structure in the region where the vapor flow path and the condensate flow path are arranged is configured to be symmetrical with respect to an axis parallel to the condensate flow path arranged in a straight line, Vapor chamber.   The vapor chamber according to claim 1, wherein all of the plurality of steam flow paths are in communication.   The structure in the region where the vapor flow path and the condensate flow path are arranged is configured to be symmetric with respect to an axis perpendicular to the condensate flow path arranged in a straight line, The vapor chamber according to claim 1.   The vapor chamber according to any one of claims 1 to 3, wherein an annular condensate flow path is provided along an edge of the closed space.   The vapor chamber according to any one of claims 1 to 4, wherein the thickness is 0.4 mm or less. A housing;
Electronic components arranged inside the housing,
An electronic apparatus comprising: the vapor chamber according to claim 1, which is disposed in contact with the electronic component directly or via another member.   7. The electronic component according to claim 6, wherein the electronic component is disposed at a position overlapping the axis by a line parallel to the condensed liquid flow path arranged in a straight line of the vapor chamber when the vapor chamber is viewed in plan. Electronic devices.

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