Vapor chamber, electronic equipment

Abstract

To provide a vapor chamber that can enhance heat transport capacity even when having a flow channel of which direction changes.SOLUTION: A vapor chamber includes a sealed space in which a working fluid is encapsulated. The sealed space includes: a capillary structure through which the working fluid moves in a state of condensate liquid; and a plurality of steam flow passages through which the working fluid moves in the state of vapor and condensate liquid; and a curved part in which a direction in which the plurality of steam flow passages extends changes.SELECTED DRAWING: Figure 3

Description

[Technical Field]

[0001] The present invention relates to a vapor chamber in which a working fluid enclosed in a sealed space moves while heat is transported. [Background technology]

[0002] Electronic devices such as personal computers, mobile phones, and tablet devices utilize electronic components like CPUs (Central Processing Units). As the amount of heat generated by these electronic components increases with improved information processing capabilities, cooling technologies are becoming increasingly important. Heat pipes are a well-known method of cooling. They utilize the phase change of a working fluid sealed inside the pipe to transport heat from a heat source to other parts, thereby diffusing and cooling the heat source.

[0003] On the other hand, in recent years, these electronic devices have become significantly thinner, necessitating thinner cooling methods than conventional heat pipes. In response to this, vapor chambers have been proposed. A vapor chamber, sometimes called a sheet-type heat pipe, is a device that applies the concept of heat transport using heat pipes to a flat plate-shaped component. In other words, in a vapor chamber, a working fluid is sealed between opposing flat plates, and the phase change of this working fluid is used to transport and diffuse heat from a heat source, thereby cooling the heat source.

[0004] Such vapor chambers are located inside electronic devices, but because many other components are also located inside these devices, there are often constraints on where the vapor chamber can be placed. As a result, it is not always possible to create a vapor chamber with a linear flow path, and it has been necessary to address these placement constraints by providing a flow path with a curved portion that changes direction, as described in Patent Document 1, for example. [Prior art documents] [Patent Documents]

[0005]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0006] However, in the vapor chamber having a flow path whose direction changes as described in Patent Document 1, there is a problem that it is difficult to enhance the heat transport capacity.

[0007] Therefore, in view of the above problems, an object of the present invention is to provide a vapor chamber capable of enhancing the heat transport capacity even when having a flow path whose direction changes. Another object is to provide an electronic device including this vapor chamber.

Means for Solving the Problems

[0008] As a result of intensive studies, the inventors have found that in a vapor chamber having a plurality of vapor flow paths whose directions change, since the lengths are different between the plurality of vapor flow paths, the flow resistance, which is the resistance when the working fluid moves through the flow path, has a large difference between the flow paths, so that the working fluid does not move in a balanced manner. And it has been found that due to the large difference in flow resistance, the heat transport capacity decreases and the assumed performance cannot be achieved. Based on these findings, the inventors have embodied and completed the present invention. The present invention will be described below.

[0009] The present application discloses a vapor chamber in which a working fluid is enclosed in a sealed space, and the sealed space is provided with a capillary structure through which the working fluid moves in a condensate state and a plurality of vapor flow paths through which the working fluid moves in a vapor and condensate state, and has a curved portion where the extending directions of the plurality of vapor flow paths change. The plurality of vapor flow paths are arranged at intervals from each other at the curved portion, and at the curved portion, the center position of the arc of the radius of curvature of at least one vapor flow path is shifted with respect to the center position of the arc of the radius of curvature of another vapor flow path.

Effects of the Invention

[0010] According to the present invention, even when the vapor chamber has a flow path with a changing direction, the heat transport capacity can be enhanced.

Brief Description of the Drawings

[0011] [Figure 1] FIG. 1(a) is a perspective view of the vapor chamber 1, and FIG. 1(b) is an exploded perspective view of the vapor chamber 1. [Figure 2] FIG. 2 is a perspective view of the first sheet 10. [Figure 3] FIG. 3 is a plan view of the first sheet 10. [Figure 4] FIG. 4 is a cross-sectional view of the first sheet 10. [Figure 5] FIGS. 5(a) and 5(b) are other cross-sectional views of the first sheet 10. [Figure 6] FIG. 6 is a view showing a partially enlarged view of the outer peripheral liquid flow path portion 14 in a plan view. [Figure 7] FIG. 7 is a view showing a partially enlarged view of the outer peripheral liquid flow path portion 14 of another example in a plan view. [Figure 8] FIG. 8(a) is a cross-sectional view focusing on the inner liquid flow path portion 15, and FIG. 8(b) is a view showing a partially enlarged view of the inner liquid flow path portion 15 in a plan view. [Figure 9] FIG. 9 is a perspective view of the second sheet 20. [Figure 10] FIG. 10 is a plan view of the second sheet 20. [Figure 11] FIG. 11 is a cross-sectional view of the second sheet 20. [Figure 12] FIG. 12 is another cross-sectional view of the second sheet 20. [Figure 13] FIG. 13 is a cross-sectional view of the vapor chamber 1. [Figure 14] FIG. 14 is an enlarged view of a part of FIG. 13. [Figure 15] FIG. 15 is another cross-sectional view of the vapor chamber 1. [Figure 16]Figures 16(a) to 16(c) illustrate examples of condensate flow path configurations. [Figure 17] Figure 17 illustrates the condensate flow path 3 and the vapor flow path 4. [Figure 18] Figure 18 is a perspective view illustrating the electronic device 40. [Figure 19] Figure 19 is a diagram illustrating the operation of the vapor chamber 1. [Figure 20] Figure 20 is an external perspective view of the vapor chamber 201. [Figure 21] Figure 21 is an exploded perspective view of the vapor chamber 201. [Figure 22] Figure 22(a) shows the third sheet 230 viewed from one side, and Figure 22(b) shows the third sheet 230 viewed from the other side. [Figure 23] Figure 23 shows a cross-section of the third sheet 230. [Figure 24] Figure 24 shows another cross-section of the third sheet 230. [Figure 25] Figure 25 shows a cross-section of the vapor chamber 201. [Figure 26] Figure 26 is an enlarged view of a portion of Figure 25. [Figure 27] Figure 27 shows another cross-section of the vapor chamber 201. [Modes for carrying out the invention]

[0012] The various embodiments will be described below based on the drawings. However, the present invention is not limited to these embodiments. In addition, the sizes and proportions of the components may be altered or exaggerated in the drawings below for clarity. Also, unnecessary parts and repeated reference numerals may be omitted for clarity.

[0013] Figure 1(a) shows an external perspective view of the vapor chamber 1 according to the first embodiment, and Figure 1(b) shows an exploded perspective view of the vapor chamber 1. For convenience, arrows (x, y, z) indicating mutually orthogonal directions are also shown in these figures and in the figures shown below, as needed. Here, the xy-plane direction is the direction along the plate surface of the flat vapor chamber 1, and the z-direction is the thickness direction.

[0014] As can be seen in Figures 1(a) and 1(b), the vapor chamber 1 in this embodiment has a first sheet 10 and a second sheet 20. As will be explained later, the first sheet 10 and the second sheet 20 are overlapped and joined (diffusion bonding, brazing, etc.) to form a hollow space between the first sheet 10 and the second sheet 20, and the working fluid is sealed in this hollow space to form a sealed space 2 (see, for example, Figure 13).

[0015] In this embodiment, the first sheet 10 is a sheet-like component as a whole, and is L-shaped in plan view. Figure 2 shows a perspective view of the first sheet 10 as seen from the inner surface 10a side, and Figure 3 shows a plan view of the first sheet 10 as seen from the inner surface 10a side. Figure 4 shows the cross-section of the first sheet 10 when cut along line IV-IV in Figure 3. The first sheet 10 has an inner surface 10a, an outer surface 10b opposite to the inner surface 10a, and a side surface 10c that spans the inner surface 10a and the outer surface 10b and forms a thickness, and a pattern for a flow path for the working fluid is formed on the inner surface 10a side. As will be described later, the inner surface 10a of the first sheet 10 and the inner surface 20a of the second sheet 20 are overlapped so that they face each other, forming a hollow space, into which the working fluid is sealed to form a sealed space 2.

[0016] The thickness of the first sheet 10 is not particularly limited, but is preferably 0.01 mm to 1.0 mm, and more preferably 0.05 mm to 0.2 mm. This increases the range of applications for a thin vapor chamber.

[0017] The first sheet 10 comprises a main body 11 and an injection section 12. The main body 11 is sheet-shaped and forms the portion through which the working fluid moves. In this embodiment, it is L-shaped and has a curved portion in plan view. The injection section 12 is the part into which the working fluid is injected into the hollow section formed by the first sheet 10 and the second sheet 20. In this embodiment, it is a rectangular sheet in plan view that protrudes from the L-shape of the main body 11 in plan view. In this embodiment, both the inner surface 10a and the outer surface 10b of the injection section 12 of the first sheet 10 are flat surfaces.

[0018] A structure for the movement of the working fluid is formed on the inner surface 10a side of the main body 11. Specifically, the structure includes an outer peripheral joint 13, an outer peripheral liquid flow channel 14, an inner liquid flow channel 15, a steam flow channel groove 16, and a steam flow channel communication groove 17 on the inner surface 10a side of the main body 11.

[0019] The outer peripheral joint portion 13 is a surface formed on the inner surface 10a side of the main body 11, along the outer circumference of the main body 11. When this outer peripheral joint portion 13 overlaps with the outer peripheral joint portion 23 of the second sheet 20 and is joined (diffusion bonding, brazing, etc.), a sealed space 2 is formed between the first sheet 10 and the second sheet 20, and the working fluid is sealed in there. Figures 3 and 4 show A 10 The width of the outer peripheral joint 13 shown can be set as appropriate as needed, but it is preferable that the smallest part be between 0.05 mm and 5.0 mm. If this width is smaller than 0.05 mm, there is a risk that the joining area will be insufficient if misalignment occurs when joining the first sheet and the second sheet. Also, if this width is larger than 5.0 mm, there is a risk that the internal volume of the sealed space will decrease, and it may not be possible to secure sufficient steam flow paths and condensate flow paths.

[0020] The outer peripheral fluid channel section 14 functions as a fluid channel and constitutes a part of the condensed fluid channel 3 (see, for example, Figure 14), which is the channel through which the working fluid passes when it condenses and liquefies. Figure 5(a) shows the part indicated by arrow Va in Figure 4, and Figure 5(b) shows the cross-section of Figure 3 along Vb-Vb. Both figures show the cross-sectional shape of the outer peripheral fluid channel section 14. Figure 6 shows an enlarged plan view of the outer peripheral fluid channel section 14 as seen from the direction indicated by arrow VI in Figure 5(a).

[0021] As can be seen from these figures, the outer peripheral fluid channel section 14 is formed along the inner surface 10a of the main body 11, along the inside of the outer peripheral joint section 13, and is provided in an annular shape along the outer circumference of the sealed space 2. In addition, the outer peripheral fluid channel section 14 has multiple fluid channel grooves 14a that extend parallel to the outer peripheral direction of the main body 11, and the multiple fluid channel grooves 14a are spaced apart in directions different from the direction in which the fluid channel grooves 14a extend. Therefore, as can be seen from Figures 5(a) and 5(b), in the cross-section of the outer peripheral fluid channel section 14, the recessed fluid channel grooves 14a and the protruding walls 14b between the fluid channel grooves 14a are formed in an uneven manner. Since the liquid flow channel groove 14a is a groove, its cross-sectional shape includes a bottom and an opening located on the opposite side of the bottom.

[0022] By providing multiple liquid flow channel grooves 14a in this manner, the depth and width of each individual liquid flow channel groove 14a can be reduced, thereby reducing the cross-sectional area of ​​the condensate flow channel 3 (see, for example, Figure 14) and enabling the use of large capillary forces. On the other hand, by having multiple liquid flow channel grooves 14a, the total internal volume of the condensate flow channel 3 can be ensured to be of an appropriate size, allowing the required flow rate of condensate to be transmitted.

[0023] Furthermore, in the outer peripheral liquid flow channel section 14, as can be seen in Figure 6, adjacent liquid flow channel grooves 14a are connected by communication openings 14c provided at intervals in the wall 14b. This promotes the equalization of the condensate volume among multiple liquid flow channel grooves 14a, allowing the condensate to flow efficiently. In addition, the communication openings 14c provided in the wall 14b adjacent to the steam flow channel groove 16 that forms the steam flow channel 4 connect the steam flow channel 4 and the condensate flow channel 3. Therefore, by configuring the communication openings 14c, the condensate generated in the steam flow channel 4 can be smoothly moved to the condensate flow channel 3, and the steam generated in the condensate flow channel 3 can be smoothly moved to the steam flow channel 4, thereby promoting the smooth movement of the working fluid.

[0024] In this embodiment, as shown in Figure 6, the communication openings 14c are positioned opposite each other at the same location in the direction in which the liquid flow channel groove 14a extends, flanking the groove. However, this is not the only option; for example, as shown in Figure 7, the communication openings 14c may be positioned at different locations in the direction in which the liquid flow channel groove 14a extends, flanking the groove. In this case, the communication openings 14c are offset in the direction in which the liquid flow channel groove 14a extends. By offsetting the communication opening 14c in this way, from the perspective of the working fluid moving through the condensate flow path 3, the communication opening 14c does not appear on both sides simultaneously, and even when the communication opening 14c appears, at least one side is always lined with a wall 14b. Therefore, a continuous capillary force can be obtained. From this perspective, by forming the communication opening 14c with an offset, a high level of capillary force acting on the working fluid can be maintained, making it possible to allow the condensate to flow smoothly.

[0025] The outer peripheral fluid flow channel section 14 having the above configuration is preferably further configured as follows. Figures 3, 4, 5(a), and 5(b) show B 10The width of the outer peripheral liquid flow channel 14 shown can be appropriately set based on the overall size of the vapor chamber, but it is preferably 0.03 mm or more and 2 mm or less. If this width is less than 0.03 mm, there is a risk that a sufficient amount of liquid will not be able to flow on the outside. Also, if this width exceeds 2 mm, there is a risk that there will not be enough space for the inner condensate flow channel and vapor flow channel.

[0026] Regarding the liquid flow channel groove 14a, the groove width indicated by C1 in Figures 5(a) and 6 is preferably 10 μm or more and 300 μm or less. Furthermore, the depth of the liquid channel groove 14a, indicated by D in Figures 5(a) and 5(b), is preferably 5 μm or more and 200 μm or less. This allows the capillary force of the liquid channel necessary for the condensate to flow to be fully exerted. Here, the depth D of the liquid channel groove is preferably smaller than the remaining sheet thickness obtained by subtracting the groove depth D from the thickness of the first sheet 10. This makes it possible to more reliably prevent the sheet from tearing when the working fluid freezes. From the viewpoint of maximizing the capillary action of the flow path, the aspect ratio (length-to-width ratio) of the flow path cross-section, expressed as C1 divided by D, is preferably greater than 1.0 or less than 1.0. Among these, from a manufacturing standpoint, it is preferable that C1 is greater than D, and the aspect ratio is preferably greater than 1.3.

[0027] Furthermore, regarding the wall 14b, the width indicated by C2 in Figures 5(a) and 6 is preferably 20 μm or more and 300 μm or less. If this width is less than 20 μm, it becomes prone to rupture due to repeated freezing and thawing of the working fluid, and if this width is greater than 300 μm, the width of the communication opening 14c becomes too large, which may hinder the smooth communication of the working fluid with the adjacent condensate flow path 3.

[0028] Regarding the communication opening 14c, it is preferable that the size of the opening along the direction in which the liquid flow channel groove 14a, indicated as C3 in Figure 6, extends, is between 20 μm and 180 μm. Furthermore, it is preferable that the pitch of adjacent communication openings 14c in the direction in which the liquid flow channel groove 14a, indicated by C4 in Figure 6, extends is 300 μm or more and 2700 μm or less.

[0029] In this embodiment, the cross-sectional shape of the liquid flow channel groove 14a is semi-elliptical, but it is not limited to this, and may be square, rectangular, trapezoidal or other quadrilateral, triangular, semicircular, with a semicircular base, with a semi-elliptical base, or a combination thereof.

[0030] Furthermore, it is preferable that the liquid flow channel groove 14a is formed continuously along the edge of the sealed space. That is, it is preferable that the liquid flow channel groove 14a extends in an annular shape around the entire circumference without being interrupted by other components. This reduces factors that hinder the movement of the condensate, allowing the condensate to move smoothly.

[0031] In this embodiment, an outer peripheral liquid flow channel 14 is provided, but the outer peripheral liquid flow channel 14 is not necessarily required. Depending on the shape of the vapor chamber, its relationship to the equipment to which it is applied, and the operating environment, an embodiment without the outer peripheral liquid flow channel 14 may be provided. In this embodiment, the outer periphery can be used as a steam flow channel, and heat can be transported to the outer periphery of the vapor chamber by steam, which may allow for even greater heat uniformity.

[0032] Returning to Figures 2 to 4, the inner liquid flow channel section 15 will be explained. The inner liquid flow channel section 15 also functions as a liquid flow channel and is a part of the condensed liquid flow channel 3 through which the working fluid passes when it condenses and liquefies. Figure 8(a) shows the part indicated by VIIIa in Figure 4. The cross-sectional shape of the inner liquid flow channel section 15 is also shown in this figure. Figure 8(b) shows an enlarged plan view of the inner liquid flow channel section 15 as seen from the direction indicated by arrow VIIIb in Figure 8(a).

[0033] As can be seen from these figures, the inner liquid flow channel section 15 is formed on the inner surface 10a of the main body 11, inside the ring of the annular outer liquid flow channel section 14 (or outer joint section 13). As can be seen from Figures 2 and 3, the inner liquid flow channel section 15 in this embodiment is a convex ridge that extends with a curved portion, and multiple (five in this embodiment) inner liquid flow channel sections 15 are arranged with intervals in a direction different from the direction in which they extend, and are positioned between the steam flow channel grooves 16. Each inner liquid flow channel section 15 has a liquid flow channel groove 15a formed in it, which is a groove parallel to the direction in which the inner liquid flow channel section 15 extends. Multiple liquid flow channel grooves 15a are arranged at predetermined intervals in a direction different from the direction in which the liquid flow channel grooves 15a extend. Therefore, as can be seen from Figures 4 and 8(a), in the cross-section of the inner liquid flow channel section 15, the recessed liquid flow channel grooves 15a and the convex parts between the liquid flow channel grooves 15a, which are walls 15b, are formed in an irregular pattern. Since the liquid flow channel groove 15a is a groove, its cross-sectional shape includes a bottom and an opening located on the opposite side of the bottom.

[0034] By providing multiple liquid flow channel grooves 15a in this manner, the depth and width of each individual liquid flow channel groove 15a can be reduced, thereby reducing the cross-sectional area of ​​the condensate flow channel 3 (see, for example, Figure 14) and enabling the use of large capillary forces. On the other hand, by having multiple liquid flow channel grooves 15a, the total internal volume of the condensate flow channel 3 can be ensured to be of an appropriate size, allowing the required flow rate of condensate to be transmitted.

[0035] Furthermore, in the inner liquid flow channel section 15, as can be seen in Figure 8(b), following the example of the outer liquid flow channel section 14, adjacent liquid flow channel grooves 15a are connected by communication openings 15c provided at intervals in the wall 15b, similar to Figure 6. This promotes the equalization of the amount of condensate among multiple liquid flow channel grooves 15a, allowing the condensate to flow efficiently. In addition, the communication openings 15c provided in the wall 15b adjacent to the steam flow channel groove 16 that forms the steam flow channel 4 connect the steam flow channel 4 and the condensate flow channel 3. Therefore, as will be explained later, by configuring the communication openings 15c, the condensate generated in the steam flow channel 4 can be smoothly moved to the condensate flow channel 3, and the steam generated in the condensate flow channel can be smoothly moved to the steam flow channel 4, thereby promoting the smooth movement of the working fluid.

[0036] In the inner liquid flow channel section 15, following the example in Figure 7, communication openings 15c may be arranged at different positions in the direction in which the liquid flow channel groove 15a extends, flanking the groove 15a. By offsetting the communication opening 15c in this way, from the perspective of the working fluid moving through the condensate flow path 3, the communication opening 15c does not appear on both sides simultaneously, and even when the communication opening 15c appears, at least one side is always lined with a wall 15b. Therefore, a continuous capillary force can be obtained. From this perspective, by forming the communication opening 15c with an offset, a high level of capillary force acting on the working fluid can be maintained, thus enabling smoother movement of the working fluid.

[0037] The inner liquid flow channel section 15 having the above configuration is preferably further equipped with the following configuration. Figures 3, 4, and 8(a) show E 10 The width of the inner liquid flow channel section 15, as shown, is preferably 100 μm to 2000 μm. Furthermore, the pitch of the multiple inner liquid flow channel sections 15 is preferably 200 μm to 4000 μm. This sufficiently reduces the flow resistance of the steam flow channel, allowing for a good balance between the movement of the working fluid in the steam flow channel and the movement of the working fluid due to capillary force in the condensate flow channel.

[0038] For the liquid flow channel groove 15a, the groove width indicated by F1 in Figures 8(a) and 8(b) is preferably 10 μm or more and 300 μm or less. Furthermore, the groove depth indicated by G in Figure 8(a) is preferably between 5 μm and 200 μm. This allows the capillary force of the condensate flow path, which is necessary for the movement of the condensate, to be fully 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 tearing when the working fluid freezes. From the viewpoint of maximizing the capillary action of the flow path, the aspect ratio (length-to-width ratio) of the flow path cross-section, expressed as F1 divided by G, is preferably greater than 1.0 or less than 1.0. Among these, from a manufacturing standpoint, it is preferable that F1 is greater than G, and the aspect ratio is preferably greater than 1.3.

[0039] Furthermore, regarding the wall 15b, the width indicated by F2 in Figures 8(a) and 8(b) is preferably between 20 μm and 300 μm. If this width is less than 20 μm, it becomes prone to rupture due to repeated freezing and thawing of the working fluid, and if this width is greater than 300 μm, the width of the communication opening 15c becomes too large, which may hinder smooth communication between the condensate flow paths 3.

[0040] Regarding the communication opening 15c, it is preferable that the size of the opening along the direction in which the liquid flow channel groove 15a, indicated by F3 in Figure 8(b), extends is 20 μm or more and 180 μm or less. Furthermore, it is preferable that the pitch of adjacent communication openings 15c in the direction in which the liquid flow channel groove 15a, indicated by F4 in Figure 8(b), extends is 300 μm or more and 2700 μm or less.

[0041] Furthermore, although the cross-sectional shape of the liquid flow channel groove 15a is semi-elliptical in this embodiment, it is not limited to this, and may be a square, rectangle, trapezoid or other quadrilateral, triangle, semicircle, semicircular base, semi-elliptical base, or a combination thereof.

[0042] Next, the steam channel groove 16 will be described. The steam channel groove 16 is the part through which the vaporized and condensed working fluids move, and it constitutes a part of the steam channel 4. Figure 3 shows the shape of the steam channel groove 16 in plan view, and Figure 4 shows the cross-sectional shape of the steam channel groove 16.

[0043] As can be seen from these figures, the steam channel groove 16 is composed of a groove formed on the inner surface 10a of the main body 11, inside the ring of the annular outer liquid channel section 14. More specifically, the steam channel groove 16 in this embodiment is formed between adjacent inner liquid channel sections 15, and between the outer liquid channel section 14 and the inner liquid channel section 15, and is a groove that extends with a curved portion. Furthermore, multiple (six in this embodiment) steam channel grooves 16 are arranged in directions different from the direction in which they extend. Accordingly, as can be seen from Figure 4, the first sheet 10 has a shape in which the inner liquid channel sections 15 are convex and the steam channel grooves 16 are concave, with repeated convex and concave patterns. Since the steam channel groove 16 is a groove, its cross-sectional shape includes a bottom and an opening located on the opposite side of the bottom.

[0044] The steam channel groove 16 only needs to be configured such that when it is combined with the steam channel groove 26 of the second sheet 20 to form a steam channel 4, the working fluid moves through the steam channel 4. Therefore, it is preferable that the steam channel groove 16 further has the following configuration. Figures 3 and 4 show H 10 The width of the steam channel groove 16 shown is preferably formed to be larger than the widths C1 and F1 of the liquid channel grooves 14a and 15a described above, and is between 100 μm and 2000 μm. On the other hand, Figure 4 shows I 10 The depth of the steam channel groove 16 shown is preferably greater than the depths D and G of the liquid channel grooves 14a and 15a described above, and is between 10 μm and 300 μm. This ensures stable movement of the working fluid when the steam channel is formed, and by making the cross-sectional area of ​​the steam channel groove larger than that of the liquid channel groove, the steam, which has a larger volume than the condensate due to the properties of the working fluid, can be moved smoothly.

[0045] Here, it is preferable that the steam channel groove 16 is configured such that, when combined with the second sheet 20 to form the steam channel 4 as will be explained later, the width of the steam channel 4 is greater than its height (size in the thickness direction). Therefore, H 10 to I 10 The aspect ratio, as shown by the value obtained by dividing by , is preferably 4.0 or higher, and more preferably 8.0 or higher.

[0046] In this embodiment, the cross-sectional shape of the steam channel groove 16 is semi-elliptical, but it is not limited to this and may be square, rectangular, trapezoidal, triangular, semicircular, with a circular base, with a semi-elliptical base, or a combination thereof.

[0047] The steam flow channel connecting groove 17 connects multiple steam flow channel grooves 16 and, in combination with the steam flow channel connecting groove 27 of the second sheet 20, forms a channel that connects multiple steam flow channels 4 formed by the steam flow channel grooves 16 at their ends. This allows for smooth movement of the working fluid generated in the steam flow channels 4 in the direction in which the inner liquid flow channel section 15 extends. Furthermore, this helps to equalize the working fluid in the steam channel 4, and allows the steam to be transported over a wider area, enabling efficient use of the condensate channel 3 through the numerous liquid channel grooves 14a and 15a.

[0048] As can be seen in Figures 2 and 3, the steam flow channel connecting groove 17 in this embodiment is formed between the outer peripheral liquid flow channel section 14 and the ends of the inner liquid flow channel section 15 and the ends of the steam flow channel groove 16 in the direction in which it extends. Figure 5(b) shows a cross-section of the steam flow channel connecting groove 17 perpendicular to the communication direction. Note that the boundary between the steam flow channel connecting groove 17 and the steam flow channel groove 16 is not necessarily formed by a shape, so for clarity, the boundary is shown as a dotted line in Figures 2 and 3.

[0049] The steam flow channel connecting groove 17 only needs to be able to connect adjacent steam flow channel grooves 16, and its shape is not particularly limited, but it can have the following configuration, for example. As shown by J in FIGS. 3 and 5(b), 10 the width of the steam flow path communication groove 17 is preferably 100 μm or more and 1000 μm or less. Also, as shown by K in FIG. 5(b), 10 the depth of the steam flow path communication groove 17 is preferably 10 μm or more and 300 μm or less, and among these, it is preferably the same as the depth I of the steam flow path groove 16. This facilitates manufacturing. 10

[0050] In this embodiment, the cross-sectional shape of the steam flow path communication groove 17 is semi-elliptical, but it is not limited to this, and it may be a quadrilateral such as a square, rectangle, trapezoid, a triangle, a semi-circle, a semi-elliptical bottom, a semi-circular bottom, or a combination thereof.

[0051] Also, in this embodiment, the first sheet 10 includes a curved portion 18c at a portion where the directions in which the liquid flow path groove 14a, the liquid flow path groove 15a, and the steam flow path groove 16 extend change. That is, the first sheet 10 includes a straight portion 18a where the liquid flow path groove 14a, the liquid flow path groove 15a, and the steam flow path groove 16 extend linearly in the x direction, a straight portion 18b where the liquid flow path groove 14a, the liquid flow path groove 15a, and the steam flow path groove 16 extend linearly in the y direction, and a curved portion 18c that connects the liquid flow path groove 14a, the liquid flow path groove 15a, and the steam flow path groove 16 in the straight portion 18a and the straight portion 18b. Therefore, one end of the curved portion 18c is connected to one straight portion 18a, the other end is connected to the other straight portion 18b, and the liquid flow path groove 14a, the liquid flow path groove 15a, and the steam flow path groove 16 are curved so that the flow direction changes from the x direction to the y direction and from the y direction to the x direction. Here, the boundary between the straight portion and the curved portion may be the point where the flow direction starts to change in each groove. The following can be considered in the same way.

[0052] And, as can be seen from FIG. 3, in the curved portion 18c of this embodiment, the liquid flow path groove 14a, the liquid flow path groove 15a, and the steam flow path groove 16 are configured such that the radius of curvature of the outer steam flow path in the arrangement direction is larger than the radius of curvature of the inner steam flow path in the arrangement direction in the direction in which these flow path grooves are arranged. Here, when we consider the curve as part of a circle or ellipse, as shown in Figure 3, the side of the curve closest to the center of the circle or ellipse is considered the "inside" of the curve, and the side opposite the center of the circle or ellipse is considered the "outside" of the curve. The shape of the curve can be considered similarly below. Furthermore, the radius of the curve is defined by considering a circle that passes through three points: two points marking the boundary between the straight section and the curved section, and one point marking the midpoint of the length of the groove in the curved section. The radius of this circle is defined as the radius of the curve. However, the shape of the curve is not limited to being a part of a perfect circle; it may also be a part of an ellipse, or a shape in which a portion of the multiple steam flow grooves arranged in the curved section is straight. The same consideration can be applied to the shape of the curved section below.

[0053] In this embodiment, each of these grooves is curved to form a concentric arc. However, the center position of the arc may be offset, and this is not the only option. Furthermore, in the curved section 18c, the radius of the curve increases as the length of each channel groove increases.

[0054] In a vapor chamber, when multiple curved flow channels are arranged, the flow channel length is shorter towards the inside in the direction of arrangement, and longer towards the outside in the direction of arrangement, resulting in a large difference in flow resistance between the inside and outside. This difference in flow resistance worsens the balance of working fluid movement in the vapor chamber, contributing to insufficient heat transport capacity. In contrast, by incorporating the curved section 18c of this embodiment, it is possible to mitigate the difference in flow resistance between the inside and outside, particularly in the vapor flow channel groove 16. This improves the balance of working fluid movement and increases heat transport capacity.

[0055] Furthermore, in the curved section 18c, the pitch of the communication openings 14c and 15c (see Figures 6 and 8(b)) provided in the walls 14b and 15b that separate the liquid flow channel grooves 14a and 15c from the steam flow channel groove 16 can be configured to be different from that of other sections (straight section 18a, straight section 18b). This means that the pitch of the communication openings in the curved section may be larger or smaller than the pitch of the communication openings in the straight section. The choice of configuration can be made by comprehensively considering the influence of the overall shape of the vapor chamber, the position of the heat source, etc., and adopting a configuration that can reduce flow resistance. Alternatively, the communication openings 14c and 15c may not be provided in this curved section 18c. In a configuration where the pitch of the communication openings in the curved section is larger than the pitch of the communication openings in the straight section, the working fluid flowing through the steam channel groove 16 (steam channel 4) is prevented from entering the communication openings 14c and 15c in the curved section 18c. In the curved section 18c, the working fluid moving through the steam channel groove 16 (steam channel 4) is subjected to a force that causes it to flow directly into the communication openings 14c and 15c, which tends to cause steam to enter the condensate channel 3 and increase the flow resistance due to the irregularities of the communication openings 14c and 15c. In contrast, by increasing the pitch of the communication openings 14c and 15c in the curved section 18c, or by eliminating the communication openings, this increase in flow resistance can be suppressed, further reducing the difference in flow resistance between each steam channel groove 16 (steam channel 4), improving the balance of working fluid movement, and potentially increasing heat transport capacity. On the other hand, in a configuration where the pitch of the communication openings in the curved section is smaller than that of the communication openings in the straight section, the steam flowing through the steam channel groove (steam channel) has more opportunities to hit the wall surface strongly in the curved section, making it more prone to condensation. By making the pitch of the communication openings in the curved section smaller than that of the straight section, the number of communication openings can be increased, allowing the condensate to be smoothly introduced into the liquid channel groove (condensate channel), and preventing the steam channel from being blocked by the condensate. This can suppress the increase in flow resistance, further reduce the difference in flow resistance between each steam channel groove (steam channel), improve the balance of the working fluid movement, and potentially increase the heat transport capacity.

[0056] Furthermore, in the curved section 18c, the width of each of the steam flow channels 16 may be changed. Specifically, the width of steam flow channels with a large radius of curvature may be increased compared to the width of steam flow channels with a small radius of curvature. This can reduce the flow resistance of steam flow channels with a large radius of curvature and a long steam travel distance. Furthermore, the groove width of steam channel grooves with a small radius of curvature may be increased compared to the groove width of steam channel grooves with a large radius of curvature. This can reduce the flow resistance of the steam channel in the curved section, which is caused by the small radius. Furthermore, the groove widths of the large-radius and small-radius steam channel grooves may be increased relative to the centrally located steam channel. Alternatively, instead of changing the width of the steam channel groove, or in conjunction with it, the depth of the steam channel groove may be changed for each channel to achieve a similar effect. By changing and adjusting the depth of the channel groove, expansion in the planar (xy-plane) direction is suppressed, which can improve heat transport capacity by securing more space for condensate channels, or improve pressure resistance reliability by allowing for a wider outer periphery joint. By the means described above, it becomes possible to further reduce the difference in flow resistance between multiple steam flow channels, thereby improving the balance of working fluid movement and increasing heat transport capacity.

[0057] Furthermore, in the curved section 18c, at least one of the width and depth of the steam flow channel groove 16 may be made larger than in the straight sections 18a and 18b. This reduces the flow resistance in the curved section 18c, where the flow resistance is high, and reduces the flow resistance of the vapor chamber as a whole, allowing the working fluid to move more smoothly and increasing the heat transport capacity.

[0058] Next, the second sheet 20 will be described. In this embodiment, the second sheet 20 is also a sheet-like component as a whole, and is curved in an L-shape when viewed from above. Figure 9 shows a perspective view of the second sheet 20 as seen from the inner surface 20a side, and Figure 10 shows a plan view of the second sheet 20 as seen from the inner surface 20a side. Figure 11 shows the cross-section of the second sheet 20 when cut along line XI-XI in Figure 10. Figure 12 shows the cross-section of the second sheet 20 when cut along line XII-XII in Figure 10. 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 spans the inner surface 20a and the outer surface 20b and forms a thickness, and a pattern is formed on the inner surface 20a side for the working fluid to move. As will be described later, the inner surface 20a of the second sheet 20 and the inner surface 10a of the first sheet 10 described above are overlapped and joined so that they face each other, forming a hollow space, into which the working fluid is sealed to form a sealed space 2.

[0059] The thickness of the second sheet 20 is not particularly limited, but is preferably 0.01 mm to 1.0 mm, and more preferably 0.05 mm to 0.2 mm. This increases the range of applications for a thin vapor chamber.

[0060] The second sheet 20 comprises a main body 21 and an injection section 22. The main body 21 is sheet-shaped and forms the portion through which the working fluid moves. In this embodiment, it is L-shaped and has a curved portion in plan view. The injection section 22 is the part into which the working fluid is injected into the hollow section formed by the first sheet 10 and the second sheet 20. In this embodiment, it is a rectangular sheet in plan view that protrudes from the L-shape of the main body 21 in plan view. In this embodiment, an injection groove 22a is formed on the inner surface 20a side of the injection section 22 of the second sheet 20, and it communicates with the inside of the main body 21 (the hollow section, the part that should become the sealed space 2) from the side surface 20c of the second sheet 20.

[0061] A structure for the movement of the working fluid is formed on the inner surface 20a side of the main body 21. Specifically, the inner surface 20a side of the main body 21 is provided with an outer peripheral joint 23, an outer peripheral fluid flow channel 24, an inner fluid flow channel 25, a steam flow channel groove 26, and a steam flow channel communication groove 27.

[0062] The outer peripheral joint portion 23 is a surface formed on the inner surface 20a side of the main body 21, along the outer circumference of the main body 21. When this outer peripheral joint portion 23 overlaps with the outer peripheral joint portion 13 of the first sheet 10 and is joined (by diffusion bonding, brazing, etc.), a hollow portion is formed between the first sheet 10 and the second sheet 20, and the working fluid is sealed in there to form a sealed space 2. Figures 10, 11, and 12 show A 20 The width of the outer peripheral joint 23 shown is the width A of the outer peripheral joint 13 of the main body 11 described above. 10 It is preferable that it be the same as [the other option].

[0063] The outer peripheral fluid channel section 24 functions as a fluid channel section and is part of the condensed fluid channel 3 (see, for example, Figure 14), which is the channel through which the working fluid passes when it condenses and liquefies.

[0064] The outer peripheral liquid channel portion 24 is formed along the inner surface 20a of the main body 21, along the inside of the outer peripheral joint portion 23, and is formed to form an annular shape along the outer circumference of the sealed space 2. In this embodiment, as can be seen from Figures 11 and 12, the outer peripheral liquid channel portion 24 of the second sheet 20 is a flat surface and flush with the outer peripheral joint portion 23 before joining with the first sheet 10. This closes the openings of at least some of the liquid channel grooves 14a of the first sheet 10 described above, forming the condensed liquid channel 3. A detailed description of the combination of the first sheet 10 and the second sheet 20 will be explained later. In the second sheet 20, the outer peripheral joint portion 23 and the outer peripheral liquid flow channel portion 24 are flush, so structurally there is no boundary line that distinguishes the two. However, for clarity, the boundary between the two is represented by a dotted line in Figures 9 and 10.

[0065] The outer peripheral fluid flow channel 24 preferably has the following configuration. Width B of the outer peripheral liquid flow channel 24 shown in Figures 10, 11, and 12 20 The width B of the outer peripheral liquid flow channel portion 14 of the first sheet 10 is not particularly limited. 10 It may be the same as, or it may be different. In this form, width B 10 and width B 20 It is the same as that. Width B 20 width B 10 When the size is reduced, at least a portion of the outer peripheral liquid flow channel section 14 will have an opening in the liquid flow channel groove 14a that is not closed by the outer peripheral liquid flow channel section 24, allowing condensate to enter more easily and vapor to escape more easily, thus enabling smoother movement of the working fluid.

[0066] In this embodiment, the outer peripheral liquid flow channel portion 24 of the second sheet 20 is configured to be a flat surface, but it is not limited to this, and liquid flow channel grooves may be provided in the same way as the outer peripheral liquid flow channel portion 14. In this case, the liquid flow channel grooves of the first sheet and the liquid flow channel grooves of the second sheet can be superimposed to form a condensed liquid flow channel 3.

[0067] Furthermore, as explained in the first sheet, the outer peripheral liquid flow channel 24 is not necessarily required in this embodiment, and the embodiment may be configured without the outer peripheral liquid flow channel 24.

[0068] Next, the inner liquid flow channel section 25 will be described. The inner liquid flow channel section 25 is also a liquid flow channel section and is one of the parts that make up the condensed liquid flow channel 3.

[0069] As can be seen in Figures 9 to 12, the inner liquid flow channel section 25 is formed on the inner surface 20a of the main body 21, inside the ring that is annular to the outer liquid flow channel section 24. In this embodiment, the inner liquid flow channel section 25 is a convex ridge that extends with a curved portion, and multiple (five in this embodiment) inner liquid flow channel sections 25 are arranged with spacing in a direction different from the direction in which they extend, and are positioned between the steam flow channel grooves 26. In this embodiment, each inner liquid channel portion 25 is formed such that its inner surface 20a side becomes a flat surface before joining with the first sheet 10. This closes the openings of at least some of the liquid channel grooves 15a of the multiple liquid channel grooves 15a of the first sheet 10 described above, thereby forming a condensed liquid channel 3. Furthermore, in the case where grooves for forming the condensed liquid channel 3 are not formed in the inner liquid channel section 25 as in this embodiment, it is preferable that the thickness of the second sheet 20 be greater than or equal to the thickness of the first sheet 10 minus the depth G of the liquid channel groove 15a (see Figure 8(a)). This prevents rupture (breakage) on the second sheet side in the vapor chamber.

[0070] In this embodiment, the inner liquid channel portion 25 of the second sheet 20 is configured to consist of a flat surface, but it is not limited to this, and liquid channel grooves may be provided in the same way as the inner liquid channel portion 15. In this case, the liquid channel grooves of the first sheet and the liquid channel grooves of the second sheet are superimposed to form a condensed liquid channel 3.

[0071] The width E of the inner liquid flow channel 25 shown in Figures 10 and 11. 20 The width E of the inner liquid flow channel 15 of the first sheet 10 is not particularly limited. 10 It may be the same as, or it may be different. In this form, width E 10and width E 20 It is the same as that. Width E 20 and width E 10 If they are different, the effect of misalignment during joining can be reduced. Note that width E 20 width E 10 If the size is reduced, at least a portion of the inner liquid flow channel section 15 will have an opening in the liquid flow channel groove 15a that is not closed by the inner liquid flow channel section 25, allowing condensed liquid to enter more easily and generated vapor to escape more easily, thus enabling smoother movement of the working fluid.

[0072] Next, the steam channel groove 26 will be described. The steam channel groove 26 is the part through which the vaporized and condensed liquid working fluids move, and constitutes a part of the steam channel 4. Figure 10 shows the shape of the steam channel groove 26 in plan view, and Figure 11 shows the cross-sectional shape of the steam channel groove 26.

[0073] As can be seen from these figures, the steam channel grooves 26 are composed of grooves with curved portions formed on the inner surface 20a of the main body 21, inside the ring of the annular outer liquid channel section 24. More specifically, the steam channel grooves 26 in this embodiment are grooves formed between adjacent inner liquid channel sections 25, and between the outer liquid channel section 24 and the inner liquid channel section 25. Furthermore, multiple (six in this embodiment) steam channel grooves 26 are arranged in directions different from the direction in which the steam channel grooves 26 extend. Accordingly, as can be seen from Figure 10, the second sheet 20 has a shape in which convex ridges are formed with the inner liquid channel section 25 being convex, and concave ridges are formed with the steam channel grooves 26 being concave, with these convex and concave shapes being repeated. Since the steam channel groove 26 is a groove, its cross-sectional shape includes a bottom and an opening located on the opposite side of the bottom.

[0074] It is preferable that the steam channel groove 26 is positioned so as to overlap in the thickness direction with the steam channel groove 16 of the first sheet 10 when combined with the first sheet 10. This allows the steam channel 4 to be formed by the steam channel groove 16 and the steam channel groove 26. Figures 10 and 11 show H 20The width of the steam channel groove 26 shown is not particularly limited, and the width H of the steam channel groove 16 of the first sheet 10 10 It may be the same as, or it may be different. In this form, the width H 10 and width H 20 It is the same as that. Width H 20 and width H 10 If they are different, the effect of misalignment during joining can be reduced. Note that the width H 20 width H 10 If the size is increased, at least a portion of the inner liquid flow channel section 15 will have an opening in the liquid flow channel groove 15a that is not closed by the inner liquid flow channel section 25, allowing condensed liquid to enter and vapor to exit more easily, thus enabling smoother movement of the working fluid. On the other hand, Figure 11 shows I 20 The depth of the steam flow channel groove 26 shown is preferably 10 μm or more and 300 μm or less.

[0075] Here, it is preferable that the steam channel groove 26 is configured such that, when combined with the first sheet 10 to form the steam channel 4 as will be explained later, the width of the steam channel 4 is greater than its height (size in the thickness direction). Therefore, H 20 to I 20 The aspect ratio, as shown by the value obtained by dividing by , is preferably 4.0 or higher, and more preferably 8.0 or higher.

[0076] In this embodiment, the cross-sectional shape of the steam channel groove 26 is semi-elliptical, but it may also be a square, rectangle, trapezoid, or other quadrilateral, a triangle, a semicircle, a semicircular base, a semi-elliptical base, or a combination thereof.

[0077] The steam channel connecting groove 27 is combined with the steam channel connecting groove 17 of the first sheet 10 to form a channel that connects the ends of the multiple steam channels 4 formed by the steam channel groove 26. This ensures that the movement of the working fluid generated in the steam channels 4 in the direction in which the inner liquid channel section 25 extends is well-balanced. Furthermore, this equalizes the working fluid in the steam channels 4, allows steam to be carried over a wider area, and enables efficient use of many condensate channels 3, thus making the movement of the working fluid smoother.

[0078] As can be seen in Figures 10 and 12, the steam flow channel connecting groove 27 in this embodiment is formed between the outer circumferential liquid flow channel 24 and the ends of the inner liquid flow channel section 25 and the ends of the steam flow channel groove 26 in the direction in which it extends. Figure 12 also shows a cross-section of the steam flow channel connecting groove 27 perpendicular to the communication direction.

[0079] Figures 10 and 12 show J 20 The width of the steam flow channel connecting groove 27 shown is not particularly limited, and the width of the steam flow channel connecting groove 17 of the first sheet 10 is J 10 It may be the same as, or width J 10 It may be different from the above. Note that the width J 20 Width J 10 When the size is increased, the opening of the liquid flow channel groove 14a in at least a portion of the outer peripheral liquid flow channel portion 14 of the first sheet 10 is arranged to form a part of the steam flow channel 4, making it easier for condensate to enter and for generated steam to exit, thereby allowing the working fluid to move more smoothly.

[0080] Width J 20 The size is preferably in the range of 100 μm to 1000 μm, as shown in Figure 12. 20 The depth of the steam flow channel communication groove 27 shown is preferably 10 μm or more and 300 μm or less.

[0081] In this embodiment, the cross-sectional shape of the steam flow channel connecting groove 27 is semi-elliptical, but it is not limited to this; it may also be a square, rectangle, trapezoid, triangle, semicircle, a semicircular base, a semi-elliptical base, or a combination thereof.

[0082] Furthermore, in this embodiment, the second sheet 20 includes a curved section 28c in the outer liquid flow channel 24, the inner liquid flow channel 25, and the steam flow channel groove 26, which is a portion where the direction of extension of these changes. That is, as can be seen from Figure 10, the second sheet 20 includes a straight section 28a in which the outer liquid flow channel 24, the inner liquid flow channel 25, and the steam flow channel groove 26 extend linearly in the x direction, a straight section 28b in which the outer liquid flow channel 24, the inner liquid flow channel 25, and the steam flow channel groove 26 extend linearly in the y direction, and a curved section 28c that connects the outer liquid flow channel 24, the inner liquid flow channel 25, and the steam flow channel groove 26 in the straight sections 28a and 28b. Therefore, one end of the curved section 28c is connected to one straight section 28a and the other end is connected to the other straight section 28b, and the flow in the outer liquid flow channel 24 and the inner liquid flow channel groove 26 changes direction from the x direction to the y direction and from the y direction to the x direction. The road section 25 and the steam flow channel groove 26 are curved.

[0083] As can be seen from Figure 10, in the curved section 28c of this embodiment, the outer liquid flow channel section 24, the inner liquid flow channel section 25, and the steam flow channel groove 26 extend in a curved manner such that the radius of curvature increases from the inside to the outside in the direction in which they are arranged.

[0084] The outer liquid flow channel 24, the inner liquid flow channel 25, and the steam flow channel groove 26 in the curved portion 28c can be considered in the same way as the curved portion 18c of the first sheet 10 described above.

[0085] Next, the structure of the vapor chamber 1 when the first sheet 10 and the second sheet 20 are combined will be described. This description will further explain the arrangement, size, shape, etc., of each component of the first sheet 10 and the second sheet 20. Figure 13 shows a cross-section of the vapor chamber 1 cut in the thickness direction along the y-direction indicated by XIII-XIII in Figure 1(a). This figure combines the diagram shown in Figure 4 on the first sheet 10 and the diagram shown in Figure 11 on the second sheet 20 to represent the cross-section of the vapor chamber 1 in this area. Figure 14 shows a magnified view of the area indicated as XIV in Figure 13. Figure 15 shows a cross-section of the vapor chamber 1 cut along the thickness direction, along the x-direction indicated by XV-XV in Figure 1(a). This figure combines the diagram shown in Figure 5(b) for the first sheet 10 and the diagram shown in Figure 12 for the second sheet 20 to represent the cross-section of the vapor chamber 1 in this area.

[0086] As can be seen from Figures 1(a), 1(b), and 13 to 15, the first sheet 10 and the second sheet 20 are arranged to overlap and joined together to form the vapor chamber 1. At this time, the inner surface 10a of the first sheet 10 and the inner surface 20a of the second sheet 20 are arranged 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 of the first sheet 10 and the injection part 22 of the second sheet 20 overlap.

[0087] The laminate of the first sheet 10 and the second sheet 20 arranges the components of the main body 11 and the main body 21 as shown in Figures 13 to 15. Specifically, it is as follows.

[0088] The vapor chamber 1 of this embodiment is particularly effective when it is thin. From this viewpoint, the thickness of the vapor chamber 1, indicated by L0 in Figures 1 and 13, is 1 mm or less, more preferably 0.4 mm or less, and even more preferably 0.2 mm or less. By making it 0.4 mm or less, the vapor chamber 1 can often be installed inside the electronic device without having to perform any processing (e.g., groove formation) to create space for the vapor chamber in the electronic device. Furthermore, according to this embodiment, even such a thin vapor chamber can maintain thermal performance while having high strength and resistance to deformation.

[0089] On the other hand, 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 to overlap, and the two are joined by joining means such as diffusion bonding or brazing. As a result, a sealed space 2 is formed between the first sheet 10 and the second sheet 20.

[0090] The outer peripheral liquid channel portion 14 of the first sheet 10 and the outer peripheral liquid channel portion 24 of the second sheet 20 are arranged to overlap. As a result, the liquid channel groove 14a of the outer peripheral liquid channel portion 14 and the outer peripheral liquid channel portion 24 form a condensate channel 3 through which the condensed liquid, which is the working fluid in a condensed and liquefied state, flows. Similarly, the inner liquid channel portion 15, which is a protrusion of the first sheet 10, and the inner liquid channel portion 25, which is a protrusion of the second sheet 20, are arranged to overlap. As a result, the liquid channel groove 15a of the inner liquid channel portion 15 and the inner liquid channel portion 25 form a condensate channel 3 through which the condensate flows.

[0091] Here, it is preferable that the cross-sectional shape of the condensate channel 3 be flattened in proportion to the thinning of the vapor chamber 1. This increases the capillary force and allows for smoother movement of the condensate, thereby maintaining a high level of heat transport capacity. More specifically, it is preferable that the ratio expressed by dividing the width of the condensate channel 3 by its height is greater than 1.0 and 4.0 or less. In this configuration, the width of the condensate flow path 3 is similar to the width F1 of the liquid flow path groove 15a, but is preferably between 10 μm and 300 μm. If the width is less than 10 μm, the flow resistance will increase and the transport capacity may decrease. On the other hand, if the width is greater than 300 μm, the capillary force will decrease and the transport capacity may also decrease. Furthermore, the height of the condensate channel 3 is preferably 5 μm to 200 μm, although this corresponds to the depth G of the liquid channel groove 15a in this embodiment. This allows the capillary force of the condensate channel necessary for movement to be fully exerted. It is also preferable that this height is less than or equal to the thickness (wall thickness) of the first sheet 10 and the second sheet 20 on one and the other side in the thickness direction (z direction) on either side of the condensate channel 3. This further prevents rupture (breakage) of the vapor chamber caused by the condensate channel 3.

[0092] In this embodiment, the cross-sectional shape of the condensate channel 3 is semi-elliptical due to the cross-sectional shapes of the liquid channel grooves 14a and 15. However, it is not limited to this and may be square, rectangular, trapezoidal, triangular, semicircular, with a semicircular base, with a semi-elliptical base, or a combination thereof. It can also be crescent-shaped.

[0093] In this embodiment, since the liquid channel grooves 14a and 15a are provided only in the first sheet 10, the height of the condensed liquid channel is based on the depth of the liquid channel grooves 14a and 15a. However, liquid channel grooves may also be provided in the second sheet 20. In this case, the liquid channel grooves of the first sheet and the second sheet overlap to form a condensed liquid channel, and the height of the condensed liquid channel will be in accordance with the sum of the depths of both liquid channel grooves.

[0094] When liquid channel grooves are provided in the first and second sheets and they are stacked to form a condensed liquid channel, the condensed liquid channel can be configured as shown in Figures 16(a) to 16(c). The example in Figure 16(a) shows that the liquid flow channel grooves of the first and second sheets are the same width and located in the same position. The example in Figure 16(b) shows that the width of the liquid channel groove in the second sheet is larger than the width of the liquid channel groove in the first sheet, but their positions coincide. In this example, a protrusion is formed in the condensate channel as indicated by P, which improves the capillary force and increases the force that moves the condensate (condensate supply force). The example in Figure 16(c) shows a case where the liquid channel grooves of the first and second sheets are the same width, but are positioned offset from each other. In this example as well, a protrusion is formed in the condensate channel as indicated by P, which improves the capillary force and increases the force that moves the condensate (condensate supply force).

[0095] Furthermore, as described above, communication openings 14c and 15c are formed in the condensate flow path 3. This allows multiple condensate flow paths 3 to communicate with each other, equalizing the condensate and enabling efficient movement of the condensate. In addition, the communication openings 14c and 15c, which are adjacent to the steam flow path 4 and connect the steam flow path 4 and the condensate flow path 3, allow the condensate generated in the steam flow path 4 to move smoothly to the condensate flow path 3, and the steam generated in the condensate flow path 3 to move smoothly to the steam flow path 4, thereby enabling rapid movement of the working fluid.

[0096] Furthermore, it is preferable that the condensate 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 a continuous annular shape along the edge of the sealed space 2. That is, it is preferable that the condensate flow path 3 formed by the outer peripheral liquid flow path section 14 and the outer peripheral liquid flow path section 24 extends in an annular shape around the entire circumference without being interrupted by other components. This reduces factors that hinder the movement of the condensate, allowing the condensate to move smoothly. However, the outer peripheral liquid flow channel is not necessarily required, and depending on the shape of the vapor chamber, its relationship to the equipment to which it is applied, and the operating environment, the outer peripheral liquid flow channel 14 may be omitted. In this configuration, the outer periphery can be used as a steam flow channel, and heat can be transported to the outer periphery of the vapor chamber by steam, which may allow for even greater heat uniformity.

[0097] The opening of the steam channel groove 16 in the first sheet 10 and the opening of the steam channel groove 26 in the second sheet 20 overlap so as to face each other, forming a channel which becomes the steam channel 4. Here, it is preferable that the cross-sectional shape of the steam channel 4 be flattened as the vapor chamber 1 is made thinner. This makes it possible to secure the surface area within the channel even when it is made thinner, and to maintain a high level of heat transport capacity. More specifically, the width W of the steam channel 4 shown in Figure 14 B Height H B In W B to H B It is preferable that the ratio, expressed as the value obtained by dividing by , is 2.0 or greater. Furthermore, from the viewpoint of ensuring even higher heat transport capacity, it is even more preferable that the ratio is 4.0 or greater.

[0098] As can be seen in Figure 15, the opening of the steam channel communication groove 17 of the first sheet 10 and the opening of the steam channel communication groove 27 of the second sheet 20 overlap and face each other to form a channel, and the ends of the multiple steam channels 4 formed by the steam channel grooves 16 and 26 are connected, forming a channel that balances the movement of the working fluid.

[0099] As described above, the sealed space 2 of the vapor chamber 1 forms a condensate flow path 3 and a vapor flow path 4 due to the shapes of the first sheet 10 and the second sheet. Figure 17 shows a diagram focusing on the condensate flow path 3 and vapor flow path formed in the sealed space 2. As can be seen from Figures 14 and 17, the vapor chamber 1 has a shape in which multiple condensate flow paths 3 are arranged between two vapor flow paths 4. This creates a configuration in which the condensate flow paths 3, through which the condensate should flow, and the vapor flow paths 4, through which both vapor and condensate move, are separated and arranged alternately, which helps to facilitate the smooth movement of the working fluid.

[0100] Through the steam channel 4 and the condensate channel 3, the working fluid, in the form of steam and condensate, moves through the steam channel 4, allowing for efficient heat transfer and diffusion. On the other hand, the condensate moves efficiently through the condensate channel 3, which is provided separately from the steam channel 4, by capillary force, thus suppressing the occurrence of dryout.

[0101] Furthermore, in the vapor chamber 1, two straight sections 6, in which the condensate flow path 3 and the vapor flow path 4 extend in different directions, are connected by a curved section 7. By forming such a flow path, even when the vapor chamber is placed in electronic equipment and there are constraints on its placement that prevent the formation of a flow path consisting solely of a straight line, the curved section 7 allows the heat generated from the heat source to be efficiently moved to a position at a distance.

[0102] This curved section 7 is formed by the curved section 18c of the first sheet 10 and the curved section 28c of the second sheet 20. Thus, one end of the curved section 7 is connected to one straight section 6, and the other end is connected to the other straight section 6, and the condensate flow path 3 and the vapor flow path 4 are curved so that the flow changes direction from the x direction to the y direction and from the y direction to the x direction.

[0103] As can be seen from Figure 17, in the curved section 7 of this embodiment, the condensate flow path 3 and the vapor flow path 4 are configured such that, in the direction in which these flow paths are arranged, the radius of curvature of the flow path on the outside in the direction of arrangement is larger than the radius of curvature of the flow path on the inside in the direction of arrangement. In this embodiment, these multiple flow channels are curved to form concentric arcs. However, it is not limited to this, and the centers of the arcs do not have to be the same. Furthermore, in this embodiment, the curved section 7 is configured such that the longer flow channels have a larger radius, while the shorter flow channels have a smaller radius.

[0104] In a vapor chamber, when multiple curved flow channels are arranged, the flow channel length is shorter towards the inside of the arrangement and longer towards the outside, resulting in a large difference in flow resistance between the inside and outside. This difference in flow resistance impairs the balance of working fluid movement in the vapor chamber, contributing to insufficient heat transport capacity. In contrast, by incorporating the curved section 7 of this embodiment, it is possible to mitigate the difference in flow resistance between the inside and outside, particularly in the vapor flow channel 4. This improves the balance of working fluid movement and increases heat transport capacity.

[0105] Furthermore, in the curved section 7, the communication openings 14c and 15c (see Figures 6 and 8(b)) provided in the wall separating the condensate flow path 3 and the vapor flow path 4 belonging to the curved section 7 can be configured differently from those in other sections (straight section 6). This means that the pitch of the communication openings in the curved section may be larger or smaller than the pitch of the communication openings in the straight section. The choice of configuration can be made by comprehensively considering the influence of the overall shape of the vapor chamber, the location of the heat source, etc., and adopting a configuration that can reduce flow resistance. Alternatively, the communication openings 14c and 15c may not be provided in the curved section 7. In a configuration where the pitch of communication openings in the curved section is larger than that of the communication openings in the straight section, it is possible to prevent the working fluid flowing through the steam channel from entering the communication openings in the curved section. In the curved section, the working fluid moving through the steam channel has a force that causes it to flow directly into the communication openings, and the flow resistance tends to increase due to the steam entering the condensate channel and the irregularities of the communication openings. In contrast, by increasing the pitch of communication openings in the curved section or eliminating the openings altogether, this increase in flow resistance can be suppressed, further reducing the difference in flow resistance between steam channels, improving the balance of working fluid movement, and potentially increasing heat transport capacity. On the other hand, in a configuration where the pitch of the communication openings in the curved section is smaller than that of the communication openings in the straight section, the steam flowing through the steam channel in the curved section has more opportunities to hit the wall surface more strongly, making it more prone to condensation. In this case, by making the pitch of the communication openings in the curved section smaller than that of the communication openings in the straight section, the number of communication openings can be increased, allowing the condensate to be smoothly introduced into the condensate channel, and preventing the steam channel from being blocked by the condensate. This can suppress the increase in flow resistance, further reduce the difference in flow resistance between steam channels, improve the balance of the movement of the working fluid, and in some cases increase the heat transport capacity.

[0106] Furthermore, in the curved section 7, the cross-sectional area of ​​the flow path may be changed for each of the multiple steam flow paths 4. Specifically, the cross-sectional area of ​​the steam flow path with a large radius of curvature may be increased compared to the cross-sectional area of ​​the steam flow path 4 with a small radius of curvature. This makes it possible to reduce the flow resistance of the steam flow path with a large radius of curvature, where the steam travels a long distance. To achieve this, the width of the steam flow path or the height of the steam flow path may be changed. Conversely, the cross-sectional area of ​​a steam channel with a small radius of curvature may be increased compared to the cross-sectional area of ​​a steam channel with a large radius of curvature. This reduces the flow resistance in the curved section caused by the small radius. To achieve this, the width or height of the steam channel can be changed. Furthermore, the cross-sectional areas of the steam channels with larger radii and smaller radii may be increased relative to the central steam channel. Here, "channel cross-sectional area" refers to the cross-sectional area of ​​the channel in a plane perpendicular to the direction in which the channel extends. By using the methods described above, it is possible to reduce the difference in flow resistance between multiple steam flow channels, thereby improving the balance of working fluid movement and increasing heat transport capacity.

[0107] Furthermore, in the curved section 7, the cross-sectional area of ​​the steam flow path 4 may be made larger than that of the straight section 6. This reduces the flow resistance in the curved section 7, which has a greater flow resistance in shape compared to the straight section 6. As a result, the flow resistance of the vapor chamber as a whole becomes smaller, allowing the working fluid to move more smoothly and increasing the heat transport capacity.

[0108] On the other hand, as shown in Figure 1, the inner surfaces 10a and 20a of the injection sections 12 and 22 overlap facing each other, and the opening on the opposite side of the bottom of the injection groove 22a of the second sheet 20 is closed by the inner surface 10a of the injection section 12 of the first sheet 10, forming an injection channel 5 that connects the outside with the hollow section between the main body 11 and the main body 21 (condensate channel 3 and vapor channel 4). However, after the working fluid is injected into the hollow section from the injection channel 5, the injection channel 5 is closed, creating a sealed space 2. Therefore, in the final form of the vapor chamber 1, the sealed space 2 is not in communication with the outside.

[0109] The sealed space 2 of the vapor chamber 1 is filled with a working fluid. The type of working fluid is not particularly limited, but any working fluid commonly used in vapor chambers, such as pure water, ethanol, methanol, or acetone, can be used.

[0110] A vapor chamber like the one described above can be fabricated, for example, as follows.

[0111] Prepare a sheet made of the material that constitutes the first sheet 10 and having the outer periphery shape of the first sheet 10, and a sheet made of the material that constitutes the second sheet 20 and having the outer periphery shape of the second sheet 20. On these sheets, the liquid channel grooves 14a, liquid channel grooves 15a, steam channel grooves 16, steam channel grooves 26, steam channel connecting grooves 17, and steam channel connecting grooves 27 described above are formed by half-etching. Half-etching is a method of removing material by etching up to a certain point in the thickness direction without penetrating the material through in the thickness direction, thereby forming grooves and depressions.

[0112] Next, the etched sheet having the shape of the first sheet 10 and the etched sheet having the shape of the second sheet 20 are placed on top of each other with their inner surfaces 10a and 20a facing each other and temporarily fixed in place. The method of temporary fixing is not particularly limited, but examples include resistance welding, ultrasonic welding, and bonding with adhesive. After temporary fixing, diffusion bonding is performed to permanently join these sheets. Alternatively, brazing may be used instead of diffusion bonding. However, in the case of a thin vapor chamber like this embodiment, the condensate flow path and vapor flow path are narrow, so if brazing is used, there is a risk that the brazing material will enter these flow paths. Furthermore, as mentioned above, strong capillary forces act in the flow paths, so there is a risk that the brazing material will spread over a wide area of ​​the flow path. From this perspective, welding methods such as diffusion bonding or ultrasonic bonding, which do not cause such problems, are preferred.

[0113] After joining, a vacuum is drawn from the formed injection channel 5 to reduce the pressure inside the hollow section. Then, working fluid is injected into the reduced-pressure hollow section from the injection channel 5, filling the hollow section 2 with working fluid. The injection channel 5 is then closed by using laser melting or crimping on the injection sections 12 and 22. This creates a sealed space 2, inside which the working fluid is stably held, forming a vapor chamber 1.

[0114] Next, we will explain the operation of the vapor chamber 1 when it is activated. Figure 18 schematically shows the vapor chamber 1 positioned inside a portable terminal 40, which is a form of electronic device. Here, the vapor chamber 1 is shown as a dotted line because it is positioned inside the housing 41 of the portable terminal 40. Such a portable terminal 40 is composed of a housing 41 that encloses various electronic components, and a display unit 42 that is exposed to the outside so that an image can be seen through an opening in the housing 41. Among these electronic components, an electronic component 30 that should be cooled by the vapor chamber 1 is positioned inside the housing 41.

[0115] The vapor chamber 1 is installed inside the casing of a portable terminal or the like, and is attached to an electronic component 30, such as a CPU, that needs to be cooled. The electronic component 30 is attached either directly to the outer surface 10b or 20b of the vapor chamber 1, or via a highly thermally conductive adhesive, sheet, tape, or the like.

[0116] Figure 19 illustrates the behavior of the working fluid. For ease of explanation, this figure is from the same viewpoint as Figure 17, focusing on the condensate flow path 3 and vapor flow path 4 formed within the sealed space 2. When the electronic component 30 generates heat, that heat is transferred through the first sheet 10 by thermal conduction, and the condensate located near the electronic component 30 in the sealed space 2 receives the heat. The condensate that receives this heat absorbs the heat, evaporates, and vaporizes. This cools the electronic component 30.

[0117] The vaporized working fluid becomes steam and moves through the steam channel 4. The vaporized working fluid may move in an oscillating manner within the steam channel 4, as shown by the solid straight arrows in Figure 19, or, although not shown, it may move in one direction away from the heat source, the electronic component 30, without oscillating. In this case, the steam flow path 4 includes the curved portion of the curved section 7. However, because the curved section 7 has the above-described configuration, the difference in flow resistance is mitigated even if the flow path length is different, and the working fluid moves through the steam flow path 4 in a balanced manner. This enables high heat transport capacity to be achieved. As the working fluid moves, it is cooled as heat is sequentially absorbed by the first sheet 10 and the second sheet 20. The first sheet 10 and the second sheet 20, having absorbed heat from the steam, transfer that heat to the casing of the portable terminal device, etc., which are in contact with their outer surfaces 10b and 20b, and finally the heat is released into the outside air. The working fluid, having had heat absorbed while moving through the steam channel 4, then condenses and liquefies.

[0118] A portion of the condensate generated in the steam channel 4 moves to the condensate channel 3 through a communication opening or the like. In this configuration, the condensate channel 3 is equipped with communication openings 14c and 15c, so the condensate is distributed to multiple condensate channels 3 through these communication openings 14c and 15c.

[0119] The condensate that enters the condensate channel 3 moves towards the heat source, the electronic component 30, due to the capillary force of the condensate channel, as shown by the dotted straight arrow in Figure 19. Then, it vaporizes again due to the heat from the heat source, the electronic component 30, and the above process is repeated.

[0120] As described above, the vapor chamber 1 allows for smooth and efficient movement of the working fluid in the vapor channel and high capillary force in the condensate channel, thereby increasing the heat transport capacity. Furthermore, by forming a flow path with a curved section 7 in the vapor chamber 1, even when there are constraints on the placement of the vapor chamber when it is installed in an electronic device and it is not possible to form a flow path that is only in a straight line, the heat generated from the heat source can be efficiently moved to a position at a distance. Furthermore, since the curved section 7 is configured such that the difference in flow resistance between the multiple steam passages 4 is reduced, the working fluid can be moved in a balanced manner, thereby increasing the heat transport capacity.

[0121] Figures 20 to 27 illustrate the vapor chamber 201 according to the second embodiment. Figure 20 is an external perspective view of the vapor chamber 201, and Figure 21 is an exploded perspective view of the vapor chamber 201.

[0122] As can be seen in Figures 20 and 21, the vapor chamber 201 has a first sheet 210, a second sheet 220, and a third sheet 230. These three sheets are stacked and joined together (diffusion bonding, brazing, etc.) so that a sealed space 202 is formed between the first sheet 210 and the second sheet 220, surrounded by the first sheet 210, the second sheet 220, and the third sheet 230 (see Figure 25), and the working fluid is sealed in this sealed space 202.

[0123] In this embodiment, the first sheet 210 is a sheet-like member as a whole. The first sheet 210 is composed of flat surfaces on both sides, and includes an inner surface 210a, an outer surface 210b opposite to the inner surface 210a, and a side surface 210c that spans the inner surface 210a and the outer surface 210b and forms the thickness.

[0124] The first sheet 210 comprises a main body 211 and an injection section 212. The main body 211 is a sheet-like portion that forms a sealed space through which the working fluid moves, and in this embodiment, it is a rectangle with rounded corners (so-called R) in a plan view. The injection section 212 is the part into which the working fluid is injected into the sealed space formed by the first sheet 210, the second sheet 220, and the third sheet 230. In this embodiment, it is a rectangular sheet in plan view that protrudes from the L-shape of the main body 211 in plan view. In this embodiment, both the inner surface 210a and the outer surface 210b of the injection section 212 of the first sheet 210 are flat surfaces.

[0125] In this embodiment, the second sheet 220 is a sheet-like member as a whole. The second sheet 220 is composed of flat surfaces on both sides, and includes an inner surface 220a, an outer surface 220b opposite to the inner surface 220a, and a side surface 220c that spans the inner surface 220a and the outer surface 220b and forms the thickness.

[0126] The second sheet 220 also has a main body 221 and an injection section 222.

[0127] In this embodiment, the third sheet 230 is a sheet that is sandwiched and overlapped between the inner surface 210a of the first sheet 210 and the inner surface 220a of the second sheet 220, and a structure for the movement of the working fluid is formed in the main body 231. Figure 22 shows a plan view of the third sheet 230. Figure 24(a) shows the surface that overlaps the second sheet 220, and Figure 24(b) shows the surface that overlaps the first sheet 210. Figure 23 shows a cross-section along the line indicated by XXII-XXII in Figure 22(a), and Figure 24 shows a cross-section along the line indicated by XXIII-XXIII in Figure 22(a).

[0128] The third sheet 230 comprises a main body 231 and an injection section 232. The main body 231 is a sheet-like portion that forms a sealed space through which the working fluid moves, and in this embodiment, it is L-shaped with a curved portion in plan view. The injection section 232 is the part into which the working fluid is injected into the sealed space formed by the first sheet 210, the second sheet 220, and the third sheet 230. In this embodiment, it is a rectangular sheet in plan view that protrudes from the L-shape of the main body 231 in plan view. An injection groove 232a is formed in the injection section 232 on the side that overlaps with the first sheet 210. The injection groove 232a can be considered in the same way as the injection groove 22a described above.

[0129] The main body 231 is equipped with an outer peripheral joint portion 233, an outer peripheral liquid flow channel portion 234, an inner liquid flow channel portion 235, a steam flow channel slit 236, and a steam flow channel communication groove 237.

[0130] The outer peripheral joint portion 233 is a portion formed along the outer circumference of the main body 231. One surface of the outer peripheral joint portion 233 overlaps with the surface of the first sheet 210 and is joined (diffusion bonding, brazing, etc.), and the other surface overlaps with the surface of the second sheet 220 and is joined (diffusion bonding, brazing, etc.). As a result, a sealed space 202 is formed surrounded by the first sheet 210, the second sheet 220, and the third sheet 230, into which the working fluid is sealed. The outer periphery joint 233 can be considered in the same way as the outer periphery joint 13 described above.

[0131] The outer peripheral fluid channel section 234 functions as a fluid channel and constitutes a part of the condensed fluid channel 3, which is the channel through which the working fluid passes when it condenses and liquefies. The outer peripheral fluid channel section 234 is formed along the inside of the outer peripheral joint section 233 of the main body 231 and is provided in an annular shape along the outer circumference of the sealed space 202. A fluid channel groove 234a is formed on the surface of the outer peripheral fluid channel section 234 that faces the second sheet 220. In this embodiment, the fluid channel groove 234a is provided only on the surface that faces the second sheet 220, but a fluid channel groove may also be provided on the surface of the outer peripheral fluid channel section 234 that faces the first sheet 210. The outer peripheral fluid flow channel portion 234 and the fluid flow channel groove 234a provided therein can be considered in the same way as the outer peripheral fluid flow channel portion 14 and the fluid flow channel groove 14a described above.

[0132] The inner liquid channel section 235 also functions as a liquid channel section and constitutes a part of the condensed liquid channel 3 through which the working fluid passes when it condenses and liquefies. The inner liquid channel section 235 is formed to extend with a curved portion inside the ring of the annular outer liquid channel section 234 of the main body 231. Multiple (five in this embodiment) inner liquid channel sections 235 are arranged in directions different from the direction of extension and are positioned between the steam channel slits 236.

[0133] On the side of the inner liquid flow channel 235 facing the second sheet 220, a liquid flow channel groove 235a is formed, which is a groove parallel to the direction in which the inner liquid flow channel 235 extends. The inner liquid flow channel 235 and the liquid flow channel groove 235a can be considered in the same way as the inner liquid flow channel 15 and the liquid flow channel groove 15a described above. In this embodiment, the liquid flow channel groove 235a is provided only on the side facing the second sheet 220, but in addition, a liquid flow channel groove may also be provided on the side of the inner liquid flow channel portion 235 facing the first sheet 210.

[0134] The steam flow channel slit 236 is a slit that constitutes the steam flow channel 4, and is the part through which the vaporized and condensed liquid working fluid moves. The steam flow channel slit 236 is formed on the inside of the ring of the annular outer peripheral liquid flow channel portion 434 of the main body 231, and consists of a curved slit. More specifically, the steam flow channel slit 236 in this embodiment is a slit formed between adjacent inner liquid flow channel portions 235, and between the outer peripheral liquid flow channel portion 234 and the inner liquid flow channel portion 235. Therefore, the steam flow channel slit 236 penetrates the third sheet 230 in the thickness direction (z direction). Furthermore, multiple (six in this embodiment) steam flow channel slits 236 are arranged in directions different from the direction of extension. Therefore, as can be seen from Figure 23, the third sheet 230 has a shape in which the outer peripheral liquid flow channel section 234 and the inner liquid flow channel section 235 and the steam flow channel slits 236 are alternately repeated.

[0135] Such a steam flow channel slit 236 can be considered in the same way as the configuration of the steam flow channel 4 formed by the combination of the steam flow channel groove 16 and the steam flow channel groove 26 described above.

[0136] In this embodiment, the cross-sectional shape of the steam flow channel slit 236 is formed by overlapping parts of an elliptical arc, with the center in the thickness direction protruding. However, it is not limited to this, and may also be a square, rectangle, trapezoid, triangle, semicircle, crescent shape, or a combination thereof.

[0137] The steam flow channel connecting groove 237 is a groove that forms a flow channel connecting multiple steam flow channel slits 236. This allows for balancing the movement of the working fluid in the steam flow channel in the direction in which the inner liquid flow channel section 235 extends. Furthermore, this helps to equalize the working fluid in the steam flow path, transport the steam over a wider area, and efficiently utilize the condensate flow path through the numerous liquid flow path grooves 234a and 235a.

[0138] In this embodiment, the steam flow channel connecting groove 237 is formed between the outer peripheral liquid flow channel section 234 and the outer peripheral liquid flow channel section 234. The steam flow channel connecting groove 237 only needs to be able to connect adjacent steam flow channel slits 236, and its shape is not particularly limited, but it can be considered in the same way as a flow channel formed by overlapping the steam flow channel connecting groove 17 and the steam flow channel connecting groove 27 described above.

[0139] The third sheet 230 also comprises straight sections 238a, 238b, and 238c, such that the vapor chamber 201 has a condensate flow path 3 and a vapor flow path 4 with straight and curved sections within the sealed space 202. The concept of these straight and curved sections is the same as that described above.

[0140] Such a third sheet 230 can be manufactured by etching each side individually, etching both sides simultaneously, press working, or cutting.

[0141] Figures 25 to 27 illustrate the structure of the vapor chamber 201 when the first sheet 210, the second sheet 220, and the third sheet 230 are combined. Figure 25 shows a cross-section along the line indicated by XXIV-XXIV in Figure 20, and Figure 26 shows an enlarged view of a part of Figure 25. Figure 27 also shows a cross-section along the line indicated by XXVI-XXVI in Figure 20.

[0142] As can be seen from Figures 20 and 25 to 27, the first sheet 210, the second sheet 220, and the third sheet 230 are arranged and joined together to form a vapor chamber 201. At this time, the inner surface 210a of the first sheet 210 and one surface of the third sheet 230 (the surface on which the liquid flow channels 234a and 235a are not located) are arranged to face each other, and the inner surface 220a of the second sheet 220 and the other surface of the third sheet 230 (the surface on which the liquid flow channels 234a and 235a are located) are arranged to face each other. The injection sections 212, 222, and 232 of each sheet are also arranged in a similar manner.

[0143] As a result, a hollow space is formed between the first sheet 210 and the second sheet 220, surrounded by the first sheet 210, the second sheet 220, and the third sheet 230, and the working fluid is sealed within this space, forming a sealed space 202. This becomes the condensate flow path 3 and the vapor flow path 4. The same concept as described above for the vapor chamber 1 can be applied to the configuration of the condensate flow path 3 and the vapor flow path 4 within these sealed spaces 202. In this embodiment, the condensed liquid channel 3 is formed only on one side in the thickness direction of the outer peripheral liquid channel section 234 and the inner liquid channel section 235. However, the embodiment is not limited to this, and the condensed liquid channel may also be formed on the other side in the thickness direction of the outer peripheral liquid channel section 234 and the inner liquid channel section 235.

[0144] In the above description, a vapor chamber was described having a curved portion at the intersection where two straight sections intersect at a 90-degree angle to form an L-shape. However, the form of the curve is not limited to this, and the above-described form of the curved portion can be applied to other forms as well. For example, the above-described curved portion can be applied to the intersections when two straight sections intersect in a T-shape, when two straight sections intersect in a cross shape, when two straight lines intersect at an acute angle (an angle less than 90 degrees) to form a V-shape, and when two straight lines intersect at an obtuse angle (an angle greater than 90 degrees) to form a V-shape. [Explanation of Symbols]

[0145] 1. Vapor chamber 2 Closed space 3. Condensate flow path 4. Steam flow path 10 First Sheet 11 Main unit 12 Injection part 13 Peripheral joint 14 Peripheral liquid flow path section 14a Liquid flow groove 14c Communication opening 15 Inner liquid flow path section 15a Liquid flow groove 15c Communication opening 16 Steam channel groove 17 Steam flow channel connecting groove 20 Second seat 21 Main unit 22 Injection part 23 Peripheral joint 24 Peripheral liquid flow path section 25 Inner liquid flow path section 26 Steam channel groove 27 Steam flow channel connecting groove 230 Third Seat 236 Steam flow channel slit

Claims

1. A vapor chamber in which a working fluid is sealed in a confined space, The vapor chamber has a sheet that forms the sealed space, The sheet is provided with an outer peripheral joint formed along its outer circumference, a capillary structure located inside the outer peripheral joint where the working fluid moves in a condensed state, and a plurality of vapor passages located inside the outer peripheral joint where the working fluid moves in a vapor and condensed state, wherein the outer peripheral joint, the capillary structure, and the vapor passages are formed on the same sheet. It has a curved section in which the direction of extension of multiple steam flow paths changes, The multiple steam passages are arranged at intervals from each other in the curved section. Multiple steam passages communicate with the capillary structure in the curved section. The radius of curvature of the steam flow path on the outside of the curved portion is greater than the radius of curvature of the steam flow path on the inside of the curved portion. The cross-sectional area of ​​the steam flow path with a small radius of curvature is larger than the cross-sectional area of ​​the steam flow path with a large radius of curvature. Vapor chamber.

2. A vapor chamber in which a working fluid is sealed in a confined space, The vapor chamber has a sheet that forms the sealed space, The sheet is provided with an outer peripheral joint formed along its outer circumference, a capillary structure located inside the outer peripheral joint where the working fluid moves in a condensed state, and a plurality of vapor passages located inside the outer peripheral joint where the working fluid moves in a vapor and condensed state, wherein the outer peripheral joint, the capillary structure, and the vapor passages are formed on the same sheet. It has a curved section in which the direction of extension of multiple steam flow paths changes, The multiple steam passages are arranged at intervals from each other in the curved section. Multiple steam passages communicate with the capillary structure in the curved section. The radius of curvature of the steam flow path on the outside of the curved portion is greater than the radius of curvature of the steam flow path on the inside of the curved portion. The cross-sectional area of ​​the steam flow path with a small radius of curvature is larger than the cross-sectional area of ​​the steam flow path with a large radius of curvature. Vapor chamber.

3. A vapor chamber in which a working fluid is sealed in a confined space, The vapor chamber has a sheet that forms the sealed space, The sheet is provided with an outer peripheral joint formed along its outer circumference, a capillary structure located inside the outer peripheral joint where the working fluid moves in a condensed state, and a plurality of vapor passages located inside the outer peripheral joint where the working fluid moves in a vapor and condensed state, wherein the outer peripheral joint, the capillary structure, and the vapor passages are formed on the same sheet. It has a curved section in which the direction of extension of multiple steam flow paths changes, The multiple steam passages are arranged at intervals from each other in the curved section. Multiple steam passages communicate with the capillary structure in the curved section. The radius of curvature of the steam flow path on the outside of the curved portion is greater than the radius of curvature of the steam flow path on the inside of the curved portion. The cross-sectional area of ​​the steam flow path with a large radius of curvature and the steam flow path with a small radius of curvature are larger than the cross-sectional area of ​​the central steam flow path. Vapor chamber.

4. A vapor chamber in which a working fluid is sealed in a confined space, The vapor chamber has a sheet that forms the sealed space, The sheet is provided with an outer peripheral joint formed along its outer circumference, a capillary structure located inside the outer peripheral joint where the working fluid moves in a condensed state, and a plurality of vapor passages located inside the outer peripheral joint where the working fluid moves in a vapor and condensed state, wherein the outer peripheral joint, the capillary structure, and the vapor passages are formed on the same sheet. It has a curved section in which the direction of extension of multiple steam flow paths changes, The multiple steam passages are arranged at intervals from each other in the curved section. Multiple steam passages communicate with the capillary structure in the curved section. The cross-sectional area of ​​the steam flow path on the inside of the curved portion is larger than the cross-sectional area of ​​the steam flow path on the outside of the curved portion. Vapor chamber.

5. A vapor chamber in which a working fluid is sealed in a confined space, The vapor chamber has a sheet that forms the sealed space, The sheet is provided with an outer peripheral joint formed along its outer circumference, a capillary structure located inside the outer peripheral joint where the working fluid moves in a condensed state, and a plurality of vapor passages located inside the outer peripheral joint where the working fluid moves in a vapor and condensed state, wherein the outer peripheral joint, the capillary structure, and the vapor passages are formed on the same sheet. It has a curved section in which the direction of extension of multiple steam flow paths changes, The multiple steam passages are arranged at intervals from each other in the curved section. Multiple steam passages communicate with the capillary structure in the curved section. The cross-sectional area of ​​the steam flow path outside the curved portion is larger than the cross-sectional area of ​​the steam flow path inside the curved portion. Vapor chamber.

6. A vapor chamber in which a working fluid is sealed in a confined space, The vapor chamber has a sheet that forms the sealed space, The sheet is provided with an outer peripheral joint formed along its outer circumference, a capillary structure located inside the outer peripheral joint where the working fluid moves in a condensed state, and a plurality of vapor passages located inside the outer peripheral joint where the working fluid moves in a vapor and condensed state, wherein the outer peripheral joint, the capillary structure, and the vapor passages are formed on the same sheet. It has a curved section in which the direction of extension of multiple steam flow paths changes, The multiple steam passages are arranged at intervals from each other in the curved section. Multiple steam passages communicate with the capillary structure in the curved section. The cross-sectional area of ​​the steam flow path inside the curved section and the cross-sectional area of ​​the flow path outside the curved section are larger than the cross-sectional area of ​​the steam flow path in the center of the curved section. Vapor chamber.

7. The vapor chamber according to any one of claims 1 to 6, wherein in the plurality of steam passages in the curved portion, the center positions of the arcs of the radius of the curve are offset.

8. The curved section is continuous with the straight section in which the multiple steam passages extend in a straight line, The vapor chamber according to any one of claims 1 to 7, wherein the curved portion has a larger flow path cross-sectional area of ​​the steam passage than the straight portion.

9. The curved section is continuous with the straight section in which the plurality of steam passages extend in a straight line, The vapor chamber according to any one of claims 1 to 7, wherein the capillary structure is arranged between the steam flow paths, and the wall separating the steam flow paths and the capillary structure is provided with a plurality of openings that connect the steam flow paths and the capillary structure.

10. The vapor chamber according to claim 9, wherein the pitch of the openings in the curved portion is different from the pitch of the openings in the straight portion.

11. The vapor chamber according to claim 10, wherein the pitch of the openings in the curved portion is smaller than the pitch of the openings in the straight portion.

12. The vapor chamber according to claim 9, wherein the curved portion is not provided with the opening.

13. The vapor chamber according to any one of claims 1 to 12, wherein the multiple vapor passages are connected.

14. The casing and Electronic components arranged inside the aforementioned housing, A vapor chamber according to any one of claims 1 to 13, which is positioned in contact with the electronic component either directly or via another member, is provided. electronic equipment.

15. A sheet for a vapor chamber in which a working fluid is sealed, It comprises an outer peripheral joint formed along the outer circumference, a capillary structure provided inside the outer peripheral joint where the working fluid moves in a condensed state, and a plurality of vapor passages provided inside the outer peripheral joint where the working fluid moves in a vapor and condensed state. It has a curved section in which the direction of extension of multiple steam flow paths changes, The multiple steam passages are arranged at intervals from each other in the curved section. Multiple steam passages communicate with the capillary structure in the curved section. The radius of curvature of the steam flow path on the outside of the curved portion is greater than the radius of curvature of the steam flow path on the inside of the curved portion. The cross-sectional area of ​​the steam flow path with a small radius of curvature is larger than the cross-sectional area of ​​the steam flow path with a large radius of curvature. Sheet for vapor chamber.

16. A sheet for a vapor chamber in which a working fluid is sealed, It comprises an outer peripheral joint formed along the outer circumference, a capillary structure provided inside the outer peripheral joint where the working fluid moves in a condensed state, and a plurality of vapor passages provided inside the outer peripheral joint where the working fluid moves in a vapor and condensed state. It has a curved section in which the direction of extension of multiple steam flow paths changes, The multiple steam passages are arranged at intervals from each other in the curved section. Multiple steam passages communicate with the capillary structure in the curved section. The radius of curvature of the steam flow path on the outside of the curved portion is greater than the radius of curvature of the steam flow path on the inside of the curved portion. The cross-sectional area of ​​the steam flow path with a small radius of curvature is larger than the cross-sectional area of ​​the steam flow path with a large radius of curvature. Sheet for vapor chamber.

17. A sheet for a vapor chamber in which a working fluid is sealed, It comprises an outer peripheral joint formed along the outer circumference, a capillary structure provided inside the outer peripheral joint where the working fluid moves in a condensed state, and a plurality of vapor passages provided inside the outer peripheral joint where the working fluid moves in a vapor and condensed state. It has a curved section in which the direction of extension of multiple steam flow paths changes, The multiple steam passages are arranged at intervals from each other in the curved section. Multiple steam passages communicate with the capillary structure in the curved section. The radius of curvature of the steam flow path on the outside of the curved portion is greater than the radius of curvature of the steam flow path on the inside of the curved portion. The cross-sectional area of ​​the steam flow path with a large radius of curvature and the steam flow path with a small radius of curvature are larger than the cross-sectional area of ​​the central steam flow path. Sheet for vapor chamber.

18. A sheet for a vapor chamber in which a working fluid is sealed, It comprises an outer peripheral joint formed along the outer circumference, a capillary structure provided inside the outer peripheral joint where the working fluid moves in a condensed state, and a plurality of vapor passages provided inside the outer peripheral joint where the working fluid moves in a vapor and condensed state. It has a curved section in which the direction of extension of multiple steam flow paths changes, The multiple steam passages are arranged at intervals from each other in the curved section. Multiple steam passages communicate with the capillary structure in the curved section. The cross-sectional area of ​​the steam flow path on the inside of the curved portion is larger than the cross-sectional area of ​​the steam flow path on the outside of the curved portion. Sheet for vapor chamber.

19. A sheet for a vapor chamber in which a working fluid is sealed, It comprises an outer peripheral joint formed along the outer circumference, a capillary structure provided inside the outer peripheral joint where the working fluid moves in a condensed state, and a plurality of vapor passages provided inside the outer peripheral joint where the working fluid moves in a vapor and condensed state. It has a curved section in which the direction of extension of multiple steam flow paths changes, The multiple steam passages are arranged at intervals from each other in the curved section. Multiple steam passages communicate with the capillary structure in the curved section. The cross-sectional area of ​​the steam flow path outside the curved portion is larger than the cross-sectional area of ​​the steam flow path inside the curved portion. Sheet for vapor chamber.

20. A sheet for a vapor chamber in which a working fluid is sealed, It comprises an outer peripheral joint formed along the outer circumference, a capillary structure provided inside the outer peripheral joint where the working fluid moves in a condensed state, and a plurality of vapor passages provided inside the outer peripheral joint where the working fluid moves in a vapor and condensed state. It has a curved section in which the direction of extension of multiple steam flow paths changes, The multiple steam passages are arranged at intervals from each other in the curved section. Multiple steam passages communicate with the capillary structure in the curved section. The cross-sectional area of ​​the steam flow path inside the curved section and the cross-sectional area of ​​the flow path outside the curved section are larger than the cross-sectional area of ​​the steam flow path in the center of the curved section. Sheet for vapor chamber.

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