JP2019105398A - Vapor chamber - Google Patents

Abstract

To provide a vapor chamber capable of improving heat transport capacity.SOLUTION: A vapor chamber comprises a first sheet 10, and a second sheet 20 stacked on and joined to the first sheet. A sealed space 2 is formed between the first sheet and the second sheet, and a working fluid is enclosed in the space. In the sealed space, a plurality of condensate passages 3 in which condensed liquid of the working fluid flows and vapor passages 4 in which vapor of the working fluid flows are formed by stacking the first sheet and the second sheet together. Some of the condensate passages are formed in the vapor passages.SELECTED DRAWING: Figure 12

Description

  The present invention relates to a vapor chamber that performs heat transfer by refluxing a working fluid enclosed in an enclosed space with phase change.

  The calorific value from the CPU (central processing unit) provided in personal computers and portable terminals such as mobile phones and tablet terminals tends to increase as the information processing capability improves, and cooling technology is important. Heat pipes are well known as a means for such cooling. This is to transfer the heat in the heat source to another site by the working fluid enclosed in the pipe, thereby diffusing the heat and cooling the heat source.

  On the other hand, in recent years, particularly in portable terminals and the like, thinning has become remarkable, and cooling means thinner than conventional heat pipes have been required. On the other hand, for example, a vapor chamber as described in Patent Document 1 has been proposed.

  The vapor chamber is an apparatus in which the concept of heat transport by a heat pipe is developed into a flat member. That is, in the vapor chamber, a working fluid is enclosed between opposing flat plates, and the working fluid performs heat transport by refluxing with phase change, transports and diffuses heat in the heat source, and generates a heat source. Cooling.

More specifically, a flow path for steam and a flow path for condensate are provided between opposed flat plates of the vapor chamber, and a working fluid is enclosed therein. When the vapor chamber is disposed at the heat source, the working fluid receives heat from the heat source and evaporates near the heat source, and becomes a gas (vapor) to move in the flow path for steam. Thereby, the heat from the heat source is smoothly transported to the position away from the heat source, and as a result, the heat source is cooled.
The working fluid in the gaseous state, which has transported the heat from the heat source, moves to a position away from the heat source, is cooled by being absorbed by the heat, condenses, and changes its phase to a liquid state. The phase-changed working fluid passes through the condensate flow path, returns to the position of the heat source, and receives heat from the heat source to evaporate and change to the gaseous state.
By the above circulation, the heat generated from the heat source is transported to a position away from the heat source to cool the heat source.

  Patent Document 1 discloses a vapor chamber (sheet-type heat pipe) in which such a flow path for steam (vapor passage) and a flow path for condensate (wick) are formed with a predetermined pattern. There is. It is said that this enables high heat transport capacity and thickness reduction.

JP, 2016-50682, A

  The demand for improvement of cooling capacity (heat transfer capacity) in recent years is increasing, and it is necessary to increase heat transfer capacity.

  Then, this invention makes it a subject to provide the vapor chamber which can raise heat transport capacity.

  As a result of intensive investigations, the inventors consider that more vigorous circulation of the working fluid is important for enhancing the heat transport capacity, and in particular, the working fluid is easily condensed and can smoothly enter the condensate channel. The structure was inspired and embodied to complete the present invention. Hereinafter, the present invention will be described. Here, although the reference numerals of the drawings are described in combination for the sake of easy understanding, the present invention is not limited to this embodiment.

  One aspect of the present invention comprises a first sheet (10) and a second sheet (20) superposed and joined to the first sheet, sealed between the first sheet and the second sheet A vapor chamber (1) in which a space (2) is formed and the working fluid is enclosed in the space, and in the closed space, the working fluid is condensed by the superposition of the first sheet and the second sheet A plurality of condensed liquid flow paths (3) through which the liquid flows and a vapor flow path (4) through which the vapor vaporized of the working fluid flows are formed, and a part of the condensed liquid flow path is formed in the vapor flow path It is a vapor chamber.

  Condensate channel (3) is provided with liquid channel grooves (14a, 15a) which are a plurality of parallel grooves, and a part of the liquid channel grooves of the plurality of liquid channel grooves is the bottom of the groove and May be arranged such that the opposite part is open and the opening forms part of the steam channel (4).

  The liquid flow grooves other than the liquid flow grooves of some of the plurality of liquid flow grooves (14a, 15a) may be configured such that the openings are closed.

  The plurality of liquid flow grooves (14a, 15a) may be configured to communicate with the adjacent liquid flow grooves through the openings (14c, 15c).

  The plurality of condensate flow channels (3) include an annular condensate flow channel extending along the outer periphery of the space (2) and a condensate flow channel disposed inside the ring of the annular condensate flow channel It may be configured to be included.

  Condensed liquid flow path (3) is formed by overlapping the ridges (15, 15 ') provided on the first sheet and the ridges (25, 25') provided on the second sheet The liquid channel groove is formed in at least one of the ridges of the first sheet and the ridges of the second sheet, and one of the ridges of the first sheet and the ridges of the second sheet is longer than the other. It may be configured to be formed.

  Of the ridges (15 ') of the first sheet and the ridges (25) of the second sheet, the ridges provided with the liquid flow channel may be formed to be long.

  According to the vapor chamber of the present invention, since the condensate can easily enter the condensate flow path, the smooth reflux of the working fluid can be promoted, and the heat transport capacity can be enhanced.

FIG. 1A is a perspective view of the vapor chamber 1, and FIG. 1B is an exploded perspective view of the vapor chamber 1. FIG. 2A is a perspective view of the first sheet 10, and FIG. 2B is a plan view of the first sheet 10. FIG. 3 is a cut surface of the first sheet 10. FIG. 4A and FIG. 4B are other cut surfaces of the first sheet 10. FIG. 5 is a plan view of the outer peripheral liquid flow channel portion 14 with a part thereof enlarged. FIG. 6 is a plan view of the outer peripheral liquid flow passage portion 14 of another example, and a partially enlarged view. FIG. 7 shows an example in which the cross-sectional shape of the liquid passage groove 14a is semi-elliptic. FIG. 8A is a cut surface focusing on the inner liquid flow passage 15, and FIG. 8B is an enlarged view of a part of the inner liquid flow passage 15 in plan view. FIG. 9 shows an example in which the cross-sectional shape of the steam flow channel 16 is semicircular. 10 (a) is a perspective view of the second sheet 20, and FIG. 10 (b) is a plan view of the second sheet 20. As shown in FIG. 11 (a) and 11 (b) are cut surfaces of the second sheet 20. FIG. FIG. 12 is a cut surface of the vapor chamber 1. FIG. 13 is an enlarged view of a part of FIG. FIGS. 14 (a) and 14 (b) are the figures which further expanded a part of FIG. FIG. 15 is another cut surface of the vapor chamber 1. FIG. 16 is a view for explaining the flow of the working fluid. FIG. 17A is a plan view of the second sheet 20 ′ of the vapor chamber 51, and FIG. 17B is a plan view of the first sheet 10 of the vapor chamber 51. 18 (a) shows a part of the cut surface of the vapor chamber 51, and FIG. 18 (b) shows another part of the cut surface of the vapor chamber 51. As shown in FIG. 19 (a) is a plan view of the second sheet 20 of the vapor chamber 61, and FIG. 19 (b) is a plan view of the first sheet 10 'of the vapor chamber 61. As shown in FIG. FIG. 20 shows a part of the cut surface of the vapor chamber 61. 21 (a) is a plan view of the second sheet 20 ′ ′ of the vapor chamber 71, and FIG. 21 (b) is a plan view of the first sheet 10 of the vapor chamber 71. FIG. 22 shows a part of the cut surface of the vapor chamber 71.

  Hereinafter, the present invention will be described based on the embodiments shown in the drawings. However, the present invention is not limited to these embodiments. In the drawings shown below, the sizes and proportions of members may be changed or exaggerated for ease of understanding. In addition, in order to make it easy to view, illustration of unnecessary parts in the description and reference numerals that are repeated may be omitted.

  FIG. 1A shows an external perspective view of the vapor chamber 1 according to the first embodiment, and FIG. 1B shows an exploded perspective view of the vapor chamber 1. In these drawings and the following drawings, arrows (x, y, z) indicating directions are also shown for convenience as necessary. Here, the xy in-plane direction is the plate surface direction of the vapor chamber 1 having a flat plate shape, and the z direction is the thickness direction.

  The vapor chamber 1 has a first sheet 10 and a second sheet 20 as can be seen from FIGS. 1 (a) and 1 (b). And between the first sheet 10 and the second sheet 20, the first sheet 10 and the second sheet 20 are overlapped and joined (diffusion joint, brazing, etc.) as described later. A sealed space 2 is formed in the space (see, for example, FIG. 12), and a working fluid is sealed in the sealed space 2.

In the present embodiment, the first sheet 10 is a sheet-like member as a whole. The perspective view which looked at the 1st sheet | seat 10 from the inner surface 10a side was represented to Fig.2 (a), and the top view which looked at the 1st sheet | seat 10 from the inner surface 10a side was each represented to FIG.2 (b). Moreover, the cut surface of the 1st sheet | seat 10 when it cut | disconnects by III-III in FIG. 2 (b) was shown in FIG.
The first sheet 10 includes an inner surface 10a, an outer surface 10b opposite to the inner surface 10a, and a side surface 10c connecting the inner surface 10a and the outer surface 10b to form a thickness, and the working fluid flows back to the inner surface 10a. A pattern for the flow path is formed. As described later, the closed space 2 is formed by overlapping the inner surface 10a of the first sheet 10 and the inner surface 20a of the second sheet 20 so as to face each other.

Such a first sheet 10 is provided with a main body 11 and a pouring portion 12. The main body 11 is in the form of a sheet forming a portion to which the working fluid flows back, and in the present embodiment, it is a rectangle in which an arc (so-called R) is formed at an angle in plan view.
The injection part 12 is a site | part which injects a working fluid with respect to the sealed space 2 (for example, refer FIG. 12) formed of the 1st sheet | seat 10 and the 2nd sheet 20, and one side which is a planar view rectangle of the main body 11 in this form. It is a sheet shape of a plane view quadrangle which protrudes from. In this embodiment, the injection portion 12 of the first sheet 10 has a flat surface on both the inner surface 10a side and the outer surface 10b side.

Although the thickness of such a 1st sheet | seat 10 is not specifically limited, 0.1 mm or more and 1.0 mm or less are preferable. This can increase the number of situations that can be applied as a thin vapor chamber.
Moreover, the material which comprises the 1st sheet | seat 10 is not specifically limited, either, It is preferable that it is a metal with high heat conductivity. These include, for example, copper and copper alloys.

  On the inner surface 10 a side of the main body 11, a structure for returning the working fluid is formed. Specifically, on the inner surface 10 a side of the main body 11, the outer periphery joint portion 13, the outer periphery liquid flow passage portion 14, the inner liquid flow passage portion 15, the steam flow passage groove 16, and the steam flow passage communication groove 17 are provided. Is configured.

The outer circumferential joint 13 is a flat surface formed on the inner surface 10 a side of the main body 11 along the outer circumference of the main body 11. A sealed space 2 is formed between the first sheet 10 and the second sheet 20 by overlapping and bonding (diffusion bonding, brazing, etc.) the outer periphery joint 13 to the outer periphery joint 23 of the second sheet 20. The working fluid is sealed here.
Although the width | variety of the outer periphery junction part 13 shown by A of FIG. 2 (b) and FIG. 3 can be suitably set as needed, it is preferable that they are 0.8 mm or more and 3 mm or less. If this width is smaller than 0.8 mm, there is a possibility that the bonding area will be insufficient when positional deviation occurs at the time of bonding of the first sheet and the second sheet. In addition, when the width is larger than 3 mm, the internal volume of the sealed space is reduced, and there is a possibility that the vapor flow path and the condensate flow path can not be sufficiently secured.

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

  The outer peripheral liquid flow path portion 14 functions as a liquid flow path portion, and is a portion that constitutes a part of the condensate flow path 3 through which the working fluid condenses and liquefies. 4 (a) shows a portion indicated by arrow IVa in FIG. 3, and FIG. 4 (b) shows a cut surface of a portion cut by IVb-IVb in FIG. 2 (b). The cross-sectional shape of the outer peripheral liquid flow passage portion 14 appears in any of the drawings. Moreover, the enlarged view which planarly viewed the outer peripheral liquid flow-path part 14 seen from the direction shown by arrow V to Fig.4 (a) was represented to FIG.

As can be seen from these figures, the outer peripheral liquid flow passage portion 14 is formed along the inner side of the outer peripheral joint portion 13 of the inner surface 10 a of the main body 11 and provided annularly along the outer periphery of the sealed space 2 There is. Further, in the outer peripheral liquid flow channel portion 14, liquid flow grooves 14a which are a plurality of grooves extending in parallel in the outer peripheral direction of the main body 11 are formed, and the plurality of liquid flow grooves 14a are the liquid flow grooves 14a. It is disposed at a predetermined interval in a direction different from the extending direction. Accordingly, as can be seen from FIGS. 4A and 4B, in the outer peripheral liquid flow channel portion 14, the liquid flow groove 14a which is a concave portion and the convex portion 14b which is between the liquid flow groove 14a in the cross section It is formed by repeating unevenness.
Here, since the liquid flow passage groove 14 is a groove, the bottom portion and the opposite portion facing the bottom portion have openings in the cross-sectional shape.

  Further, by providing the plurality of liquid flow grooves 14a in this manner, the depth and width of the liquid flow grooves 14a per one can be reduced, and the flow cross-sectional area of the condensate flow path 3 (see FIG. 14) Can be used to make large capillary forces. On the other hand, a plurality of liquid flow grooves 14a are combined to secure a suitable size for the flow path cross-sectional area of the condensate flow path 3 as a whole, and it is possible to flow the condensate with a necessary flow rate.

Furthermore, in the outer peripheral liquid flow channel portion 14, as can be seen from FIG. 5, the adjacent liquid flow channel grooves 14 a communicate with each other by the liquid communication opening 14 c at a predetermined interval. As a result, equalization of the amount of condensed liquid is promoted among the plurality of liquid flow grooves 14a, so that the condensed liquid can be efficiently flowed, and smooth working fluid can be returned.
In this embodiment, as shown in FIG. 5, the liquid communication opening is opposed to the same position in the width direction (direction orthogonal to the direction in which the liquid flow groove 14a extends) across the liquid flow groove 14a of the one liquid flow groove 14a. The part 14c is arrange | positioned. However, the present invention is not limited to this, and for example, as shown in FIG. 6, it differs in the width direction (direction orthogonal to the direction in which the liquid flow groove 14a extends) across the liquid flow groove 14a. The fluid communication opening 14 c may be disposed at the position. That is, the liquid communication openings 14c are arranged in a so-called staggered arrangement.

It is preferable that the peripheral liquid flow passage portion 14 having the above-described configuration further has the following configuration.
The width of the outer peripheral liquid flow passage 14 shown by B in FIGS. 2 (b), 3, 4 (a) and 4 (b) can be appropriately set based on the size of the entire vapor chamber and the like. And 0.3 mm or more and 2 mm or less. If this width is smaller than 0.3 mm, there is a possibility that a sufficient amount of liquid refluxing on the outside can not be obtained. If the width exceeds 2 mm, the space for the inner liquid flow path and the steam flow path may not be sufficiently obtained.
The width B is preferably larger than the width S (see FIG. 11) of the outer peripheral liquid flow passage 24 of the second sheet. Thereby, as described later, the opening of the liquid flow channel groove 14a is arranged to form a part of the vapor flow channel 4 in at least a part of the outer peripheral liquid flow channel portion 14, and the condensate enters from here As it becomes easy, the condensate can be more smoothly refluxed.

The groove width indicated by C in FIGS. 5 and 4A of the liquid flow groove 14a is preferably 20 μm or more and 200 μm or less. The depth of the groove indicated by D in FIGS. 4A and 4B is preferably 5 μm or more and 200 μm or less. Thereby, the capillary force of the liquid flow path necessary for the reflux can be sufficiently exerted.
From the viewpoint of exerting the capillary force of the channel more strongly, the aspect ratio (aspect ratio) in the channel cross section represented by C / D is preferably larger than 1.0 or smaller than 1.0. Among them, C> D is preferable from the viewpoint of production, and the aspect ratio is preferably larger than 1.3.

In the present embodiment, the cross-sectional shape of the liquid flow channel groove 14a is rectangular but is not limited thereto. It is not limited thereto, and square, trapezoidal, etc., square, triangle, semicircular, semielliptical, bottom is semicircular, bottom is semielliptical Or the like. FIG. 7 shows an example in which the liquid flow grooves are semi-elliptical. With this shape, it is possible to produce a liquid channel groove using etching.
Among these, a square shape is preferable because the surface tension is easily acted by the presence of the corner by the inside corner and the liquid reflux tends to be smoothly performed by the capillary force.

  Moreover, it is preferable that the pitch of the adjacent liquid flow-path part 14a in several liquid flow-path groove | channel 14a is 40 micrometers or more and 600 micrometers or less. Thereby, it is possible to prevent the deformation of the flow path due to deformation during bonding or assembly while raising the density of the condensate flow path.

With regard to the liquid communication opening 14c, the size of the opening along the direction in which the liquid flow channel groove 14a shown in E of FIG. 5 extends is preferably 20 μm to 180 μm.
The pitch of the adjacent liquid communication openings 14c in the direction in which the liquid flow grooves 14a shown in FIG. 5 extend is preferably 300 μm to 2700 μm.

  Returning to FIG. 2 and FIG. 3, the inner liquid flow passage portion 15 will be described. The inner liquid flow passage portion 15 also functions as a liquid flow passage portion, and is a portion that constitutes a part of the condensate flow passage 3 through which the working fluid condenses and liquefies. FIG. 8A shows the portion indicated by VIIIa in FIG. The cross-sectional shape of the inner liquid flow path 15 is also shown in this figure. Moreover, the enlarged view which planarly viewed the inner liquid flow-path part 15 seen from the direction shown to FIG. 8 (a) by the arrow VIIIb was shown in FIG.8 (b).

As can be seen from these figures, the inner liquid flow passage portion 15 is formed on the inner side of the ring of the outer peripheral liquid flow passage portion 14 which is an annular portion of the inner surface 10 a of the main body 11. As can be seen from FIGS. 2A and 2B, the inner liquid flow passage portion 15 of the present embodiment is a convex stripe extending in a direction (x direction) parallel to the long side of the main body 11 in a plan view rectangle. A plurality (three in the present embodiment) of inner liquid flow passage portions 15 are arranged at predetermined intervals in a direction (y direction) parallel to the short side.
In each inner liquid flow passage portion 15, a liquid flow passage groove 15a which is a groove parallel to the extending direction of the inner liquid flow passage portion 15 is formed, and the plurality of liquid flow passage grooves 15a are the liquid flow passage grooves 15a. It is disposed at a predetermined interval in a direction different from the extending direction. Therefore, as can be seen from FIGS. 3 and 8A, in the inner liquid flow passage 15, the liquid flow grooves 15a, which are concaves, and the convex portions 15b, which are between the liquid flow grooves 15a, are repeatedly uneven in the cross section. It is formed.
Here, since the liquid passage groove 15a is a groove, the bottom portion and the opposite portion facing the bottom portion have openings in the cross-sectional shape.

  Thus, by providing the plurality of liquid flow grooves 15a, the depth and width of each liquid flow groove 15a can be reduced, and the flow cross-sectional area of the condensate flow path 3 (see FIG. 14) can be reduced. Can use large capillary forces. On the other hand, by making the liquid flow grooves 15a plural, the flow path cross-sectional area of the condensate flow path 3 as a whole as a whole is secured to have a suitable size, and it is possible to flow the condensate with a necessary flow rate.

Further, as can be seen from FIG. 8B, the adjacent liquid flow grooves 15a communicate with each other by the liquid communication opening 15c at predetermined intervals. As a result, the equalization of the amount of condensed liquid is promoted among the plurality of liquid flow grooves 15a, and the condensed liquid can be efficiently flowed, so that the working fluid can be smoothly returned.
As in the case of the communication openings 14c, the communication openings may be arranged in a so-called staggered arrangement, as in the case of the communication openings 14c.

It is preferable that the inner liquid flow path unit 15 having the above-described configuration further includes the following configuration.
It is preferable that the width | variety of the inner side liquid flow path part 15 shown by G in FIG.2 (b), FIG. 3, FIG. 8 is 100 micrometers or more and 200 micrometers or less. The width G is preferably larger than the width T (see FIG. 11A) of the inner liquid flow passage 25 of the second sheet 20. Thereby, as described later, the opening of the liquid flow channel groove 15a can be arranged to form a part of the vapor flow channel 4 in at least a part of the inner liquid flow channel portion 15, and condensation from here Since the liquid can easily enter, it is possible to reflux the condensate more smoothly.
Moreover, it is preferable that the pitch of several inner side liquid flow path part 15 is 200 micrometers or more and 4000 micrometers or less. Thereby, the flow path resistance of the steam flow path can be sufficiently reduced, and the movement of the steam and the reflux of the condensate can be performed in a well-balanced manner.

The groove width indicated by H in FIGS. 8A and 8B for the liquid flow groove 15a is preferably 20 μm or more and 200 μm or less. Further, the depth of the groove indicated by J in FIG. 8A is preferably 5 μm or more and 200 μm or less. Thereby, the capillary force of the condensate flow path necessary for refluxing can be sufficiently exerted.
From the viewpoint of exerting the capillary force of the channel more strongly, the aspect ratio (aspect ratio) in the channel cross section represented by H / J is preferably larger than 1.0 or smaller than 1.0. Among them, H> J is preferable from the viewpoint of production, and the aspect ratio is preferably larger than 1.3.

Further, in the present embodiment, the cross-sectional shape of the liquid flow channel groove 15a is rectangular, but not limited to this, it is not limited thereto, and square, trapezoid or other quadrangle, triangle, semicircular, semielliptical, bottom semicircular, bottom semicircular Or the like. According to the example of FIG. 7, it is also possible to make it semi-elliptical. With this shape, it is possible to produce a liquid channel groove using etching.
Among them, a square shape is preferable because the surface tension is easily acted by the presence of the corner by the inside corner and the reflux of the liquid tends to be smoothly performed by the capillary force.

  The pitch of the adjacent liquid flow grooves 15a in the plurality of liquid flow grooves 15a is preferably 40 μm or more and 600 μm or less. While increasing the density of the liquid flow path, it is possible to prevent the flow path from being deformed and deformed during bonding or assembly.

With regard to the liquid communication opening 15c, the size of the opening along the direction in which the liquid flow channel groove 15a shown by K in FIG. 8B extends is preferably 20 μm to 180 μm.
The pitch of the adjacent liquid communication openings 15c in the direction in which the liquid flow grooves 15a extend, as indicated by L in FIG. 8B, is preferably 300 μm or more and 2700 μm or less.

  Next, the steam flow channel 16 will be described. The steam flow channel 16 is a part of the steam flow channel 4 at which the working fluid is vaporized and passes through. 2B shows the shape of the steam flow passage groove 16 in plan view, and FIG. 3 shows the cross-sectional shape of the steam flow passage groove 16 respectively.

As can be understood from these figures, the steam flow channel 16 is formed by a groove formed inside the ring of the annular peripheral liquid flow channel portion 14 in the inner surface 10 a of the main body 11. Specifically, the steam flow channel groove 16 of this embodiment is formed between the adjacent inner liquid flow channel portions 15 and between the outer peripheral liquid flow channel portion 14 and the inner liquid flow channel portion 15, and the plan view of the main body 11 A rectangular groove extending in a direction (x direction) parallel to the long side. A plurality (four in the present embodiment) of steam flow grooves 16 are arranged in a direction (y direction) parallel to the short side. Therefore, as can be seen from FIG. 3, the first sheet 10 has the outer peripheral liquid flow passage portion 14 and the inner liquid flow passage portion 15 as convex stripes in the y direction, and the unevenness formed by the steam flow channel grooves 16 is repeated. It has a different shape.
Here, since the steam flow passage groove 16 is a groove, an opening is provided in the bottom portion and the opposite side portion facing the bottom portion in the cross-sectional shape.

It is preferable that the steam flow channel 16 having such a configuration further has the following configuration.
The width of the steam flow passage groove 16 shown by M in FIGS. 2B and 3 is at least 100 μm or more and 2000 μm or less larger than the width C and width H of the liquid flow grooves 14a and 15a described above. Is preferred. In addition, the pitch of the steam flow channel 16 is usually determined by the pitch of the inner liquid flow channel portion 15.
On the other hand, the depth of the steam flow channel 16 shown by N in FIG. 3 is larger than at least the depth D and the depth J of the liquid flow channels 14a and 15a described above, and is 10 μm to 300 μm. preferable.
As described above, by making the flow passage cross-sectional area of the steam flow passage groove larger than that of the liquid flow passage groove, it is possible to smoothly reflux the steam whose volume is larger than that of the condensate due to the nature of the working fluid.

In the present embodiment, the cross-sectional shape of the steam flow channel 16 is rectangular, but not limited to this, it may be square, square, trapezoidal, etc., triangular, semicircular, semielliptical, circular at the bottom, judgment circular or the like. FIG. 9 shows an example in which the steam flow channel 16 is semicircular. With this shape, it is possible to produce a steam channel groove using etching.
Since the steam flow path can smoothly return the working fluid by reducing the flow resistance of the steam, the cross-sectional shape of the flow path can also be determined from this point of view.

  Although an example in which one steam flow passage groove 16 is formed between adjacent inner liquid flow passages 15 is described in the present embodiment, the present invention is not limited to this, and two or more may be formed between adjacent inner liquid flow passages. The steam flow grooves may be arranged side by side.

  The steam flow passage communicating groove 17 is a groove that brings the plurality of steam flow passage grooves 16 into communication with each other. As a result, the steam in the plurality of steam flow grooves 16 can be equalized, or the steam can be carried to a wider range, and many liquid flow grooves 14a and 15a (condensed liquid flow path 3) can be efficiently used. As a result, the working fluid can be more smoothly returned.

  As can be seen from FIGS. 2 (a) and 2 (b), the steam flow passage communication groove 17 of this embodiment has both ends in the extending direction of the inner liquid flow passage portion 15 and both ends in the extending direction of the steam flow passage groove 16. It is formed between the part and the outer peripheral liquid flow path part 14. FIG. 4B shows a cross section orthogonal to the communication direction of the steam flow passage communication groove 17. Since the boundary between the steam flow passage communicating groove 17 and the steam flow passage 16 does not necessarily form a boundary due to the shape, the boundary is not easy to understand in FIGS. 2 (a) and 2 (b). Expressed by dotted lines.

The steam flow passage communicating groove 17 may be formed so as to allow the adjacent steam flow passage grooves 16 to communicate with each other, and the shape thereof is not particularly limited. For example, the following configuration can be provided. .
It is preferable that the width | variety of the steam flow-path communicating groove 17 shown by P in FIG.2 (b) and FIG.4 (b) is 100 micrometers or more and 1000 micrometers or less.
In addition, the depth of the steam flow passage communication groove 17 indicated by Q in FIG. 4B is preferably 10 μm or more and 300 μm or less, and among them, the same as the depth N of the steam flow passage groove 16 preferable. This facilitates manufacture.

Although the cross-sectional shape of the steam channel communicating groove 17 is rectangular in this embodiment, the present invention is not limited to this. The shape is not limited to this, and square, trapezoidal, etc. quadrangle, triangle, semicircular, semielliptical, bottom semicircular, bottom semicircular, etc. It may be According to the example of FIG. 9, it can be made semicircular. With this shape, it is possible to produce a steam channel communication groove using etching.
Since the steam flow passage communicating groove can smoothly reflux the working fluid by reducing the flow resistance of the steam, the shape of the flow passage cross section can also be determined from this point of view.

Next, the second sheet 20 will be described. In the present embodiment, the second sheet 20 is also a sheet-like member as a whole. FIG. 10A is a perspective view of the second sheet 20 as viewed from the inner surface 20a side, and FIG. 10B is a plan view of the second sheet 20 as viewed from the inner surface 20a. Moreover, the cut surface of the 2nd sheet | seat 20 when it cut | disconnects by XIa-XIa to FIG. 10 (b) at FIG. 11 (a) was shown. Moreover, the cut surface of the 2nd sheet | seat 20 when it cut | disconnects by XIb-XIb in FIG.11 (b) at FIG.11 (b) was shown.
The second sheet 20 includes an inner surface 20a, an outer surface 20b opposite to the inner surface 20a, and a side surface 20c connecting the inner surface 20a and the outer surface 20b to form a thickness, and a pattern in which the working fluid flows back to the inner surface 20a. Is formed. As described later, a closed space is formed by overlapping the inner surface 20a of the second sheet 20 and the inner surface 10a of the first sheet 10 described above so as to face each other.

Such a second sheet 20 includes a main body 21 and an injection part 22. The main body 21 is a sheet-like portion that forms a portion to which the working fluid flows back, and in the present embodiment, is a rectangle in which a circular arc (so-called R) is formed at a corner in plan view.
The injection part 22 is a part which injects a working fluid with respect to the sealed space 2 (refer FIG. 12) formed of the 1st sheet | seat 10 and the 2nd sheet | seat 20. It is a sheet shape of a plane view quadrangle which protrudes from. In the present embodiment, the injection groove 22a is formed on the inner surface 20a side of the injection portion 22 of the second sheet 20, and the side surface 20c of the second sheet 20 communicates with the inside of the main body 21 (the portion to be the sealed space 2). ing.
The thickness of the second sheet 20 and the material to be configured can be considered similarly to the first sheet 10.

  On the inner surface 20 a side of the main body 21, a structure for returning the working fluid is formed. Specifically, on the inner surface 10 a side of the main body 21, the outer periphery joint portion 23, the outer periphery liquid flow passage portion 24, the inner liquid flow passage portion 25, the steam flow passage groove 26, and the steam flow passage communication groove 27 are provided. ing.

The outer circumferential joint portion 23 is a flat surface formed on the inner surface 20 a side of the main body 21 along the outer circumference of the main body 21. A sealed space 2 is formed between the first sheet 10 and the second sheet 20 by overlapping and bonding (diffusion bonding, brazing, etc.) the outer periphery joint 23 to the outer periphery joint 13 of the first sheet 10. The working fluid is sealed here.
It is preferable that the width of the outer peripheral bonding portion 23 shown by R in FIGS. 10B, 11A, and 11B is the same as the width A of the outer peripheral bonding portion 13 of the main body 11 described above.

  Further, holes 23 a penetrating in the thickness direction (z direction) are provided at four corners of the main body 21 in the outer peripheral joint portion 23. The holes 23 a function as positioning means at the time of superposition with the first sheet 10.

  The outer peripheral liquid flow path portion 24 is a liquid flow path portion, and is a portion which constitutes a part of the condensate flow path 3 through which the working fluid condenses and is liquefied.

The outer peripheral liquid flow passage portion 24 is formed along the inner side of the outer peripheral joint portion 23 of the inner surface 20 a of the main body 21, and is formed in an annular shape along the outer periphery of the sealed space 2. In the present embodiment, the outer peripheral liquid flow passage portion 24 of the second sheet 20 is a flat surface and flush with the outer peripheral joint portion 23 as can be seen from FIGS. 11 (a) and 11 (b). Thereby, the opening of the liquid flow path groove 14a of at least one part among the plurality of liquid flow path grooves 14a of the first sheet 10 described above is closed to form the condensate flow path 3. Detailed aspects regarding the combination of the first sheet 10 and the second sheet 20 will be described later.
In this way, in the second sheet 20 as described above, since the outer peripheral bonding portion 23 and the outer peripheral liquid flow path portion 24 are flush with each other, there is no boundary line that structurally distinguishes the two. However, for the sake of easy understanding, the boundary between the two is indicated by a dotted line in FIG.

It is preferable that the outer peripheral liquid channel portion 24 have the following configuration.
10 (b), 11 (a), and 11 (b), the width of the peripheral liquid flow passage 24 shown by S is smaller than the width B of the peripheral liquid flow passage 14 of the first sheet 10. Is preferred. Thereby, as described later, in at least a part of the outer peripheral liquid flow channel portion 14, the opening of the liquid flow channel groove 14a is opened without being closed by the outer peripheral liquid flow channel portion 24, and the condensate easily enters from here Therefore, it is possible to reflux the condensate more smoothly.
From this point of view, the size of the width S is such that B / 2 ≦ S ≦ B ₁ in relation to the width B of the peripheral liquid flow channel portion 14 of the first sheet 10 shown in FIG. 4A. Is preferred. Here, B ₁ is a position which is half the width of the liquid passage groove 14 a closest to the vapor passage groove 16 among the liquid passage grooves 14 a disposed in the outer peripheral liquid passage portion 14, and the outer peripheral liquid passage It means the distance with the outer peripheral joint 13 side end of the portion 14. If the width S is smaller than B / 2, the number of the liquid flow grooves 14a which can close the opening decreases, and there is a possibility that the capillary force in the condensed liquid flow path 3 may be insufficient. Further, there is a possibility that the width S is larger the aperture of the exposed are liquid flow path groove 14a is reduced to the steam flow path 4 from B _1, insufficient flow of the condensate liquid flow path groove 14a.

  Next, the inner liquid flow passage 25 will be described. The inner liquid flow passage portion 25 is also a liquid flow passage portion, and is a portion constituting the condensate flow passage 3.

As shown in FIGS. 10 (a), 10 (b), 11 (a) and 11 (b), the inner liquid flow passage 25 is the outer peripheral liquid flow passage 24 of the inner surface 20a of the main body 21. It is formed more inside. The inner liquid flow passage portion 25 of the present embodiment is a convex stripe extending in a direction (x direction) parallel to the long side of the main body 21 in a plan view rectangle, and a plurality of (three in the present embodiment) inner liquid flow passage portion 25 Are arranged at predetermined intervals in a direction parallel to the short side (y direction).
In the present embodiment, the surface on the inner surface 20 a side of each inner liquid flow passage 25 is formed by a flat surface. Thereby, the opening of the liquid flow path groove 15a of at least one part among the plurality of liquid flow path grooves 15a of the first sheet 10 described above is closed to form the condensate flow path 3.

It is preferable that the width of the inner liquid flow passage 25 shown by T in FIGS. 10B and 11A is smaller than the width G of the inner liquid flow passage 15 of the first sheet 10. Thereby, as described later, the opening of the liquid flow channel groove 15a is not closed by the inner liquid flow channel portion 25 in at least a part of the inner liquid flow channel portion 15, and the condensate easily enters from here. It is possible to smoothly reflux the condensate.
From this point of view, the size of the width T is such that G ₂ ≦ T ≦ G ₁ in relation to the width G of the inner liquid flow passage portion 15 of the first sheet 10 shown in FIG. preferable.
Here, as shown in FIG. 8A, G ₁ is a position at which the width of the first liquid flow groove 15 a from the vapor flow groove 16 side is half of the plurality of liquid flow grooves 15 a. Distance between
The G ₂ is, as shown in FIG. 8 (a), among the plurality of liquid flow grooves 15a, the steam flow passage 16 side end of the steam flow path groove 16 side second liquid flow path groove 15a It is the distance between departments.
If the width T is smaller than G ₂ , the number of the liquid flow grooves 15 a that can close the opening decreases, so there is a possibility that the capillary force in the condensate flow path 3 may be insufficient. Further, there is a possibility that the width T is less opening of the liquid flow path groove 15a which is exposed to the steam flow path 4 becomes greater than G _1, insufficient flow of the condensate liquid flow path groove 15a.

  Next, the steam flow channel 26 will be described. The steam flow channel 26 is a portion through which the working fluid evaporates and vaporizes, and constitutes a part of the steam flow channel 4. The shape of the steam flow passage groove 26 in plan view is shown in FIG. 10 (b), and the cross-sectional shape of the steam flow passage groove 26 is shown in FIG. 11 (a).

As can be understood from these figures, the steam flow channel 26 is formed by a groove formed inside the ring of the outer peripheral liquid flow channel 24 which is an annular portion of the inner surface 20 a of the main body 21. Specifically, the steam flow channel groove 26 of this embodiment is formed between the adjacent inner liquid flow channel portions 25 and between the outer peripheral liquid flow channel portion 24 and the inner liquid flow channel portion 25, and the plan view of the main body 21 A rectangular groove extending in a direction (x direction) parallel to the long side. A plurality of (four in the present embodiment) steam flow grooves 26 are arranged in a direction (y direction) parallel to the short side. Therefore, as can be seen from FIG. 11A, the second sheet 20 is formed with a convex stripe in which the outer peripheral liquid flow passage 24 and the inner liquid flow passage 25 are convex in the y direction. A concave groove is formed to have a shape in which these irregularities are repeated.
Here, since the steam flow passage groove 26 is a groove, an opening is provided in the bottom portion and the opposite side portion facing the bottom portion in the cross-sectional shape.

  The steam flow channel 26 is preferably disposed at a position overlapping the steam flow channel 16 of the first sheet 10 in the thickness direction when combined with the first sheet 10. Thus, the steam flow channel 4 can be formed by the steam flow channel 16 and the steam flow channel 26.

It is preferable that the width of the steam flow passage groove 26 shown by U in FIGS. 10B and 11A is larger than the width M of the steam flow passage groove 16 of the first sheet 10. As a result, as described later, the opening of the liquid passage groove 15a is exposed to the vapor passage 4 in at least a part of the inner liquid passage portion 15 of the first sheet 10, so that the condensate easily enters. It is possible to reflux the condensate more smoothly.
On the other hand, the depth of the steam flow passage groove 26 shown by V in FIG. 11A is preferably 10 μm or more and 300 μm or less.

In the present embodiment, the cross-sectional shape of the steam flow channel 26 is rectangular, but it may be square, such as square, trapezoidal, etc., triangular, semicircular, semielliptical, semicircular at the bottom, semielliptical at the bottom, or the like. According to the example of FIG. 9, it can be made semicircular. With this shape, it is possible to produce a steam channel groove using etching.
Since the steam flow path can smoothly reflux the working fluid by reducing the flow resistance of the steam, the cross-sectional shape of the flow path can also be determined from this point of view.

  Although an example in which one steam flow channel groove 26 is formed between adjacent inner liquid flow channels 25 has been described in the present embodiment, the present invention is not limited thereto, and two or more may be formed between adjacent inner liquid flow channels. The steam flow grooves may be arranged side by side.

  The steam flow passage communication groove 27 is a groove that causes the plurality of steam flow grooves 26 to communicate with each other, and constitutes a part of the steam flow passage 4. As a result, the steam in the plurality of steam channels 4 can be equalized, and the steam can be carried to a wider range, and many condensate channels 3 can be efficiently used. It is possible to make the reflux more smooth.

  As can be seen from FIGS. 10 (b) and 11 (b), the steam flow passage communication groove 27 of this embodiment has both ends in the extending direction of the inner liquid flow passage 25 and both ends in the extending direction of the steam flow groove 26. It is formed between the portion and the outer peripheral liquid flow passage 24. Further, a cross section orthogonal to the communication direction of the steam flow passage communication groove 27 appears in FIG.

The width of the steam flow channel communication groove 27 shown by W in FIGS. 10B and 11B is preferably larger than the width P of the steam flow channel communication groove 17 of the first sheet 10, and is 50 μm to 200 μm. It is more preferable to be larger than the width P in the following range. Thereby, as described later, in at least a part of the outer peripheral liquid flow path portion 14 of the first sheet 10, the opening of the liquid flow path groove 14a is disposed so as to form a part of the steam flow path 4 Condensate easily enters, and the condensate can be more smoothly refluxed.
On the other hand, it is preferable that the depth of the steam flow-path communicating groove 27 shown by X in FIG.11 (b) is 10 micrometers or more and 300 micrometers or less.

In the present embodiment, the cross-sectional shape of the steam channel communication groove 27 is rectangular, but not limited to this, it may be a square, a square such as a trapezoid, a triangle, a half circle, a half ellipse, a bottom half circle, a bottom half circle, etc. It may be. According to the example of FIG. 9, it can be made semicircular. With this shape, it is possible to produce a steam channel communication groove using etching.
Since the steam channel can be smoothly refluxed by reducing the flow resistance of the steam, the shape of the channel cross section can also be determined from this point of view.

Next, the structure when the first sheet 10 and the second sheet 20 are combined to form the vapor chamber 1 will be described. By this description, the arrangement, the size, the shape, and the like of the components included in the first sheet 10 and the second sheet 20 are further understood.
FIG. 12 shows a cut surface of the vapor chamber 1 cut in the thickness direction along the y direction indicated by XII-XII in FIG. In this drawing, the drawing shown in FIG. 3 of the first sheet 10 and the drawing shown in FIG. 11A of the second sheet 20 are combined to show the cut surface of the vapor chamber 1 at this part. is there.
FIG. 13 is an enlarged view of a portion shown by XIII in FIG. 12, and FIG. 14 (a) is a further enlarged view of the overlapping portion of the inner liquid flow passage portion 15 and the inner liquid flow passage portion 25 in FIG. The figure which expanded the part which the outer peripheral liquid flow-path part 14 and the outer peripheral liquid flow-path part 24 overlapped among FIG.
FIG. 15 shows a cut surface of the vapor chamber 1 cut in the thickness direction along the x direction indicated by XV-XV in FIG. This figure is a combination of the diagram shown in FIG. 4B of the first sheet 10 and the diagram shown in FIG. 11B of the second sheet 20. It is done.

  As can be seen from FIGS. 1 (a), 1 (b), and 12 to 15, the first sheet 10 and the second sheet 20 are arranged and joined so as to be a vapor chamber 1 ing. At this time, the inner surface 10a of the first sheet 10 and the inner surface 20a of the second sheet 20 are disposed to face each other, and the main body 11 of the first sheet 10 and the main body 21 of the second sheet overlap. The injection portion 12 and the injection portion 21 of the second sheet 20 overlap. In this embodiment, the relative positional relationship between the first sheet 10 and the second sheet 20 is configured to be appropriate by aligning the holes 13a of the first sheet 10 with the holes 23a of the second sheet 20. ing.

  By the laminated body of such a 1st sheet | seat 10 and the 2nd sheet | seat 20, each structure comprised to the main body 11 and the main body 21 is arrange | positioned so that it may appear in FIGS. Specifically, it is as follows.

  The outer circumferential joint 13 of the first sheet 10 and the outer circumferential joint 23 of the second sheet 20 are disposed so as to overlap each other, and they are joined by joining means such as diffusion joining or brazing. Thereby, the sealed space 2 is formed between the first sheet 10 and the second sheet 20.

The outer peripheral liquid flow passage portion 14 of the first sheet 10 and the outer peripheral liquid flow passage portion 24 of the second sheet 20 are arranged to overlap. As a result, the liquid flow path groove 14a of the outer peripheral liquid flow path portion 14 and the outer peripheral liquid flow path portion 24 form the condensed liquid flow path 3 through which the condensed liquid flows, which is a state in which the working fluid is condensed and liquefied.
Here, as can be seen from FIGS. 12 to 15, in the present embodiment, the width B of the outer peripheral liquid flow passage portion 14 of the first sheet 10 is greater than the width S of the outer peripheral liquid flow passage portion 24 of the second sheet 20. Is also formed large. Thus, the outer peripheral liquid flow passage portion 24 of the second sheet 20 does not overlap with respect to the liquid flow passage groove 14a on the side of the vapor flow passage 4 among the plurality of liquid flow passage grooves 14a provided in the outer peripheral liquid flow passage portion 14 Therefore, the opening is not blocked. Accordingly, at this portion, an opening is formed to face the second sheet 20 as indicated by α in FIGS. 13 to 15, and the opening forms a part of the steam flow path 4, and the steam flow It is in communication with the passage 4.
By disposing a part of the condensate flow path in the vapor flow path in this manner, the condensate can easily flow into the liquid flow path groove 14a, which is the condensate flow path, and the working fluid can be more smoothly returned. Become.

  On the other hand, with respect to a groove of the liquid flow groove 14a whose opening is closed by the outer peripheral liquid flow passage 24, since four sides become a wall in the cross section, the capillary force works strongly, and smooth liquid flow is performed .

The inner liquid flow passage portion 15 which is a ridge of the first sheet 10 and the inner liquid flow passage portion 25 which is a ridge of the second sheet 20 are disposed so as to overlap each other. As a result, the liquid flow passage groove 15 a of the inner liquid flow passage portion 15 and the inner liquid flow passage portion 25 form the condensed liquid flow passage 3 through which the condensate flows.
Here, as can be seen from FIGS. 12 to 15, in the present embodiment, the width G of the inner liquid flow passage portion 15 of the first sheet 10 is greater than the width T of the inner liquid flow passage portion 25 of the second sheet 20. Is also formed large. As a result, the inner liquid flow passage 25 of the second sheet 20 does not overlap with the liquid flow passage groove 15a on the side of the vapor flow passage 4 among the plurality of liquid flow grooves 15a provided in the inner liquid flow passage 15 Therefore, the opening is not blocked. Accordingly, at this portion, an opening is formed to face the second sheet 20 as indicated by β in FIGS. 13 to 15, and the opening forms a part of the steam flow path 4, and the steam flow It is in communication with the passage 4.
By arranging at least a part of the condensate flow passage in the vapor flow passage as described above, the condensate can easily flow into the liquid flow passage groove 15a, which is a condensate flow passage, and the working fluid can be more smoothly returned. become.

  On the other hand, with regard to a groove of the liquid flow groove 15a whose opening is closed by the inner liquid flow passage portion 25, the four sides act as walls in the cross section, and the capillary force works strongly, and smooth liquid flow is performed. .

The opening of the steam flow passage groove 16 of the first sheet 10 and the opening of the steam flow passage groove 26 of the second sheet 20 overlap so as to face each other to form a flow passage, which becomes the steam flow passage 4 through which the steam flows.
Here, as can be seen from FIGS. 12 to 14, in the present embodiment, the width U of the steam flow channel 26 of the second sheet 20 is larger than the width M of the steam flow channel 16 of the first sheet 10. It is formed. Thereby, as described above, at least a part of the condensate flow channel is disposed in the steam flow channel, and the condensate flows into the liquid flow channel groove 15a from the opening of the liquid flow channel groove 15a which is the condensate flow channel, Reflux of the working fluid is smoother.

As can be seen from FIG. 15, the opening of the steam flow passage communicating groove 17 of the first sheet 10 and the opening of the steam flow passage communicating groove 27 of the second sheet 20 overlap to form an overlapping flow passage. It becomes the steam flow path 4.
Here, in the present embodiment, the width W of the steam flow passage communication groove 27 of the second sheet 20 is formed larger than the width P of the steam flow passage communication groove 17 of the first sheet 10. Thereby, as described above, at least a part of the condensate flow channel is disposed in the steam flow channel, and the condensate is the condensate flow channel from the openings of the liquid flow channel grooves 14a and 15a, the liquid flow channel grooves 14a and 15a. It flows inside and the return of working fluid becomes smoother.
As shown in FIG. 15, in the steam flow channel 4 by the steam flow channel communicating portions 17 and 27, the liquid flow channel groove 15 a of the inner liquid flow channel portion 15 at the longitudinal direction end of the inner liquid flow channel portions 15 and 25. The opening of the liquid flow path portion 15a appears so as to face the second sheet 20 as shown by .gamma. In FIG. There is. Also by this, at least a part of the condensate flow path is disposed in the steam flow path, and the condensate easily flows into the liquid flow path groove 15a which is the condensate flow path 3, and the reflux of the working fluid Become smoother.

On the other hand, as shown in FIG. 1, the injection parts 12 and 22 also overlap so that the inner surfaces 10a and 20a face each other, and the opening on the opposite side to the bottom part of the injection groove 22a of the second sheet 20 is the first sheet An injection flow passage 5 is formed which is closed by the inner surface 10 a of the injection portion 12 of 10 and which communicates the outside with the sealed space 2 (condensed liquid flow passage 3 and steam flow passage 4) between the main body 11 and 21.
However, since the injection channel 5 is closed after the working fluid is injected from the injection channel 5 into the sealed space 2, the final form vapor chamber 1 communicates with the outside and the sealed space 2. Absent.

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

The vapor chamber as described above can be produced, for example, as follows.
Liquid channel grooves 14a and 15a, steam channel grooves 16 and 26, and steam channel communication grooves 17 and 27 are formed by half etching on a metal sheet having an outer peripheral shape of the first sheet 10 and the second sheet 20. Do.
Next, the inner surfaces 10a and 20a of the first sheet 10 and the second sheet 20 are overlapped so as to face each other, and are positioned using the holes 13a and 23a as positioning means, and temporary fixing is performed. Although the method of temporary fixing is not particularly limited, resistance welding, ultrasonic welding, adhesion with an adhesive, and the like can be mentioned.
After temporary fixing, diffusion bonding is performed to permanently bond the first sheet 10 and the second sheet 20. In addition, you may join by brazing instead of diffusion bonding.

  After bonding, vacuum drawing is performed from the formed injection channel 5 to decompress the enclosed space 2. Thereafter, the working fluid is injected from the injection flow channel 5 into the depressurized enclosed space 2, and the working fluid is introduced into the enclosed space 2. Then, melting or laser melting is applied to the injection portions 12 and 22 or the injection flow path 5 is closed. As a result, the working fluid is stably held inside the sealed space 2.

Next, the operation of the vapor chamber 1 will be described.
The vapor chamber 1 is installed in a housing such as a portable terminal and attached to an object to be cooled such as a CPU. The object to be cooled is attached to the outer surface 10 b or the outer surface 20 b of the vapor chamber 1 directly or via a highly thermally conductive adhesive, sheet, tape or the like. There is no particular limitation on which position of the outer surfaces 10a and 10b the object to be cooled is attached to, and is appropriately set in relation to the arrangement of other members in a portable terminal or the like. In the present embodiment, as shown by the dotted line in FIG. 1A, the object to be cooled 30, which is a heat source to be cooled, is disposed at the center of the main body 11 in the xy direction of the outer surface 10a of the first sheet 10. Accordingly, in FIG. 1A, the object to be cooled 30 is represented by a dotted line because it is a position where it can not be seen as a blind spot.
FIG. 16 shows a diagram for explaining the flow of the working fluid. For ease of explanation, the second sheet 20 is omitted in this figure, and the inner surface 10 a of the first sheet 10 is shown so as to be visible.

  When the object to be cooled 30 generates heat, the heat is conducted in the first sheet 10 by heat conduction, and the condensate present in the closed space 2 at a position close to the object to be cooled 30 receives heat. The condensate which receives this heat absorbs the heat, evaporates and evaporates. Thereby, the object to be cooled 30 is cooled.

The vaporized working fluid becomes steam and flows and moves in the steam flow path 4 as shown by a solid linear arrow in FIG. Since the flow occurs in the direction away from the object to be cooled 30, the vapor moves away from the object to be cooled 30.
The steam in the steam flow path 4 separates from the object to be cooled 30 which is a heat source, moves to the outer peripheral portion of the vapor chamber 1 having a relatively low temperature, and heat is sequentially transferred to the first sheet 10 and the second sheet 20 during the movement. It is cooled while being robbed. The first sheet 10 and the second sheet 20 which have taken heat from the steam transfer heat to the casing of the portable terminal or the like in contact with the outer surfaces 10b and 20b, and finally the heat is released to the outside air.

The working fluid which has been deprived of heat while moving through the steam flow path 4 condenses and liquefies. The condensate adheres to the wall surface of the steam flow path 4. On the other hand since the steam flow path 4 is continuously vapor is flowing, the condensate 13, as pushed by the steam as indicated by the arrow Z ₂ in FIG. 15, moves to the condensate flow path 3 . The condensed liquid flow path 3 of the present embodiment is provided with the liquid communication openings 14c and 15c as shown in FIGS. 5 and 8B, so the condensed liquid passes through the liquid communication openings 14c and 15c. It is distributed to a plurality of condensate channels 3.
Furthermore, in the vapor chamber 1 of the present embodiment, since a part of the condensate flow path 3 is provided in the steam flow path 4, the condensate has a thickness direction as shown by the arrow Z ₃ in FIGS. 13 and 15. To the condensate channel 3 so as to be pushed in by the vapor. Therefore, the condensate can easily enter the condensate flow path 3 and the working fluid can be returned smoothly.

Condensate that has entered the condensate flow path 3 approaches the object to be cooled 30 which is a heat source as represented by a dotted straight arrow in FIG. 16 due to capillary action by the condensate flow path 3 and pressure from steam. To move.
In particular, with regard to a part of the condensate flow channels 3 not disposed in the steam flow channel 4, the openings of the liquid flow grooves 14a and 15a are blocked by the second sheet 20, so that four sides thereof are walls in the cross section. Can increase the capillary force. This enables smoother transfer of the condensate.
And it vaporizes again with the heat from the cooling object 30 which is a heat source, and the above is repeated.

  As described above, according to the vapor chamber 1, the inflow of the condensate into the condensate flow channel is smoothly performed, so that the working fluid is well refluxed, and the heat transport amount can be increased.

  Hereinafter, other forms of the vapor chamber will be described. In the drawings showing other embodiments, the same reference numerals are given to components that can be configured with the same idea as the configuration described in the first embodiment, and the description will be omitted.

  FIGS. 17 and 18 illustrate a vapor chamber 51 according to the second embodiment. The figure which looked at 2nd sheet | seat 20 'from inner surface side with Fig.17 (a), and the figure which looked at the 1st sheet | seat 10 from inner surface with FIG.17 (b) was shown. FIG. 18 (a) is a cross section of the vapor chamber 51 at the portion indicated by XVIIIa-XVIIIa in FIG. 17 (a) and FIG. 17 (b). FIG. 18 (b) is a cross section of the vapor chamber 51 at the portion shown by XVIIIb-XVIIIb in FIG. 17 (a) and FIG. 17 (b).

In the vapor chamber 51 of the present embodiment, the first sheet 10 is the same as the vapor chamber 1.
Further, in the second sheet 20 ′, a part (two in the present embodiment) of the inner liquid flow passage 25 ′ is formed longer than the inner liquid flow passage of the first sheet. Then, the end reaches the outer peripheral liquid flow passage 24.
According to this, as shown in FIG. 18 (b) in contrast to FIG. 18 (a), a part of the vapor flow path is narrowed by the inner liquid flow path portion 25 ′, and the condensate flow for this portion There is no part where the passage is located in the steam flow path.
However, according to this, since there is no steam channel communication groove at this portion, the strength of the second sheet 20 'can be increased, and the strength of the entire vapor chamber can also be increased. In particular, the vapor chamber is easily deformed because vacuuming and bonding are performed in its manufacturing process. On the other hand, in the vapor chamber 51, it is possible to suppress the deformation by forming the inner liquid flow passage 25 'at least in part.

  FIGS. 19 and 20 illustrate the vapor chamber 61 according to the third embodiment. FIG. 19A shows the second sheet 20 as viewed from the inner surface side, and FIG. 19B shows the first sheet 10 'as viewed from the inner surface. Moreover, FIG. 20 is a cut surface of the vapor chamber 61 in the part shown by XX-XX in FIG. 19 (a) and FIG.19 (b).

In the vapor chamber 61 of the present embodiment, the second sheet 20 is the same as the vapor chamber 1.
Further, in the first sheet 10 ′, the inner liquid flow passage portion 15 ′ is formed longer than the inner liquid flow passage portion 25 of the second sheet 20. Then, the steam flow passage communication groove is not formed, and the end portion reaches the outer peripheral liquid flow passage portion 14.
According to this, as can be seen from FIG. 20, the steam flow channel is narrowed with respect to the inner liquid flow channel portion 15 ′, but the size in which the condensate flow channel (liquid flow channel groove) is disposed in the steam flow channel It can be increased. Therefore, the condensate is more likely to enter the condensate flow path at the site, and the smooth reflux of the working fluid is improved.
Further, since there is no steam flow channel communicating groove at this portion, the strength of the first sheet 10 'can be enhanced, and the strength of the entire vapor chamber can be enhanced. In particular, in the vapor chamber, it is easily deformed because vacuuming and bonding are performed in the manufacturing process. On the other hand, in the vapor chamber 61, it is possible to suppress the deformation by adopting a structure like the inner liquid flow passage 15 '.

  FIGS. 21 and 22 illustrate a vapor chamber 71 according to the fourth embodiment. FIG. 21 (a) shows the second sheet 20 ′ ′ viewed from the inner surface side, and FIG. 21 (b) shows the first sheet 10 viewed from the inner surface side. a) It is a cut surface of the vapor chamber 71 in the part shown by XXII-XXII in FIG.21 (b).

In the vapor chamber 71 of the present embodiment, the first sheet 10 is the same as the vapor chamber 1.
Further, in the second sheet 20 ′ ′, the inner liquid flow passage portion 25 of the second sheet 20 ′ ′ is formed longer than the inner liquid flow passage portion 15 of the first sheet 10, and the steam flow passage communication groove 27 ′ ′ is As compared with the steam flow passage communication groove 27 of the second sheet 20, the width of the second sheet 20 is narrowed so as to be closer to the outer peripheral liquid flow passage portion 24 side.
According to this, as can be seen by comparing FIG. 22 with FIG. 15, in the steam flow channel communication groove, the steam flow path is narrowed at this portion, and the condensate flow of the inner liquid flow path portion 15 at this portion The path is not located in the steam flow path. However, the peripheral liquid flow channel portion 14 can be in the form of being disposed in the steam flow channel 4.
According to this, since the steam flow passage communicating groove is formed narrow, the strength of the second sheet 20 ′ ′ can be increased, and the strength of the entire vapor chamber can be increased. In particular, in the vapor chamber, the manufacturing process thereof In the vapor chamber 71, the deformation can be suppressed.
On the other hand, since the outer peripheral liquid flow passage portion 14 can be formed in the vapor flow passage 4, as described above, it is possible to smooth the reflux of the condensate.

DESCRIPTION OF SYMBOLS 1 Vapor chamber 2 sealed space 3 condensate flow path 4 steam flow path 10 1st sheet 10a inner surface 10b outer surface 10c side surface 11 main body 12 injection part 13 outer periphery joint part 14 outer peripheral liquid flow path part 14a liquid flow path groove 14c liquid communication opening 15 Inner liquid flow passage portion 15a Liquid flow passage groove 15c Liquid communication opening 16 Steam flow passage groove 17 Steam flow passage communication groove 20 Second sheet 20a Inner surface 20b Outer surface 20c Side surface 21 Main body 22 Injection portion 23 Outer peripheral joint portion 24 Outer peripheral liquid flow passage portion 25 inner liquid flow path portion 26 steam flow path groove 27 steam flow path communication groove

Claims (7)

A first sheet and a second sheet overlapped and joined to the first sheet, and a sealed space is formed between the first sheet and the second sheet, and the space is operated A vapor chamber filled with fluid,
In the enclosed space, a plurality of condensate flow paths through which liquid condensed with the working fluid flows by overlapping the first sheet and the second sheet, and a vapor flow path through which the vapor of the working fluid vaporizes And are formed,
A vapor chamber in which a part of the condensate flow channel is formed in the steam flow channel. The condensate channel is provided with liquid channel grooves which are a plurality of parallel grooves,
A part of the plurality of liquid flow grooves is opened at a portion opposite to the bottom of the groove, and the opening forms a part of the steam flow The vapor chamber according to claim 1.   The vapor chamber according to claim 2, wherein the opening is blocked in another liquid flow passage groove other than the liquid flow passage groove among the plurality of liquid flow passage grooves.   The vapor chamber according to claim 2, wherein the plurality of liquid flow grooves are in communication with the adjacent liquid flow grooves via an opening.   The plurality of condensate flow channels include an annular condensate flow channel extending along the outer periphery of the space, and a condensate flow channel disposed inside the ring of the annular condensate flow channel. The vapor chamber according to any one of Items 1 to 4. The condensate flow path is formed by overlapping a ridge provided on the first sheet and a ridge provided on the second sheet,
The liquid channel groove is formed in at least one of the ridges of the first sheet and the ridges of the second sheet,
The vapor chamber according to any one of claims 2 to 5, wherein one of the ridges of the first sheet and the ridges of the second sheet is formed longer than the other.   The vapor chamber according to claim 6, wherein a convex stripe provided with the liquid channel groove is formed long among the convex stripe of the first sheet and the convex stripe of the second sheet.

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