JP2011080679A - Heat transfer device and electronic equipment - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a heat transfer device enabling stable heat transfer and electronic equipment including the heat transfer device. <P>SOLUTION: An evaporation part 7 constituted of a plurality of evaporation structures 71 is provided in the heat receiving part 4 of a heat spreader 1 filled with a refrigerant. The evaporation structure 71 includes a lateral face 72 facing a flowing part 6 and a plurality of recesses 74 having openings 73 at a plurality of positions different from each other in the Z-axis direction of the lateral face 72, respectively. The recess 74 includes an inclination part 78 inclined to the direction containing components of the Z-axis direction. The inclination part 78 is provided at a portion closer to the heat receiving part 4 on the inner face of the recess 74 so as to form a V groove 61 between the two evaporation structures 71 adjacent to each other sandwiching the flowing part 6. Thus, at various height of a liquid level of a liquid refrigerant, a meniscus face having an efficient shape to evaporate and flow the liquid refrigerant can be formed. <P>COPYRIGHT: (C)2011,JPO&INPIT

Description

  The present invention relates to a heat transport device that is thermally connected to a heat source of an electronic device, and an electronic device including the heat transport device.

  A heat spreader, a heat pipe, a CPL (Capillary Pumped Loop), or the like is connected to a heat source of an electronic device, for example, a CPU (Central Processing Unit) of a PC (Personal Computer), and absorbs and transports heat from the heat source. A heat transport device is used. As a heat transport device, a heat transport device made of a solid metal made of a copper plate or the like, and recently, a phase change heat transport device having an evaporation section and a working fluid has been proposed (for example, Patent Document 1). .

  The phase change type heat transport device described in Patent Document 1 has a substantially V-shaped cross section capable of generating a capillary force with respect to a liquid phase working fluid on an inner wall surface of a portion to which a heat source is thermally connected. The evaporation groove is provided. In this heat transport device, when the heat from the heat source is transmitted to the liquid-phase working fluid in the evaporation groove and the working fluid is heated, the working fluid evaporates into a gas phase. Due to such a phase change of the working fluid, heat is diffused throughout the heat transport device.

JP 2006-140256 (paragraphs [0027]-[0031], FIG. 4)

  In such a phase change type heat transport device, the liquid level position of the liquid-phase working fluid in the evaporation groove fluctuates up and down in accordance with the heat density of the heat source connected to the evaporation section. When the liquid surface position is lowered in the groove having a substantially V-shaped cross section, the liquid surface position of the working fluid is likely to be biased depending on the connection position of the heat source and the like. If the liquid level position is biased, the supply of the working fluid into the evaporation groove is locally insufficient, which may cause dryout. On the other hand, when the liquid level rises in the groove having a substantially V-shaped cross section, the capillary radius of the meniscus that determines the capillary force increases. When the capillary radius is increased, the capillary force is decreased and there is a possibility that the liquid-phase working fluid is not circulated well. Further, when the capillary radius is increased, the thin region of the liquid film between the liquid surface and the wall surface of the groove is reduced, and the evaporation amount of the working fluid may be reduced.

  In view of the circumstances as described above, an object of the present invention is to provide a heat transport device capable of stably transporting heat regardless of vertical fluctuations in the liquid surface position of the working fluid, and an electronic apparatus equipped with the heat transport device. It is to provide.

In order to achieve the above object, a heat transport device according to an embodiment of the present invention includes a heat receiving unit, a condensing unit, and an evaporating unit.
The heat receiving part is for receiving heat from a heat source.
The condensing unit is disposed to face the heat receiving unit in the first direction, and condenses the working fluid from a gas phase to a liquid phase.
The evaporation section includes a plurality of evaporation structures disposed in at least one direction orthogonal to the first direction with a first flow section through which the working fluid can flow. The evaporating structure has inclined surfaces that open at a plurality of different positions in the first direction so as to face the first flow part and are inclined in a direction including the component in the first direction inside. Having a plurality of recesses.

  According to the heat transport device, the inclined surfaces are provided at a plurality of different positions in the first direction of the two evaporation structures adjacent to each other with the first flow part interposed therebetween. Thereby, in the several height range from which the liquid level of a working fluid differs, a liquid surface of an efficient shape can be ensured when evaporating a working fluid and moving it to a 1st distribution part. Thereby, an evaporation part can evaporate a working fluid efficiently.

  The plurality of evaporation structures may be provided in a long shape along a second direction that is orthogonal to the first direction and the arrangement direction of the plurality of evaporation structures.

  According to the heat transport device, the working fluid moves in the second direction in the space between the adjacent evaporation structures. The moved working fluid is supplied to the area where the liquid level is lowered. Thereby, the liquid level position of the working fluid in an evaporation part can be kept equal, and generation | occurrence | production of dry out can be suppressed.

  The inclined surface may be provided in a portion near the heat receiving portion on the inner surface of the concave portion so that a V-groove portion is formed between two adjacent evaporation structures sandwiching the first circulation portion. Good.

  According to the heat transport device, a plurality of positions that differ in the first direction due to the inclined surfaces provided at a plurality of positions that differ in the first direction of the two evaporation structures adjacent to each other across the first flow part. Are integrally provided with a V-groove. For this reason, since the liquid level of the working fluid stored in the V-groove is in contact with the inclined surface, the working fluid is evaporated and moved to the first circulation part in a plurality of height ranges having different liquid levels of the working fluid. In this case, it is possible to secure an efficient liquid level. Thereby, an evaporation part can evaporate a working fluid efficiently.

  The concave portion may include a second circulation portion that moves the liquid-phase working fluid in the second direction by a capillary force at a position spaced apart from the opening with the inclined surface interposed therebetween.

  According to the heat transport device, the working fluid moves in the second direction by the capillary force in the second circulation section in a plurality of height ranges having different liquid levels of the working fluid. The moved working fluid is supplied to a region where the liquid level of the working fluid is lowered in the V groove. Thereby, the liquid level position of the working fluid in the V groove can be kept uniform.

The evaporating structure may be made of a porous material.
According to the above heat transport device, the working fluid is evaporated and circulated to the first circulation section in a plurality of height ranges having different liquid levels of the working fluid by the large number of pores of the porous material. Thus, an efficient thin region of the liquid film can be secured. Thereby, an evaporation part can evaporate a working fluid efficiently.

Carbon nanotubes may be generated on the surface of the evaporation structure.
According to the heat transport device, since the carbon nanotube has a nanoscale structure on the surface, the contact area of the liquid refrigerant can be increased, and evaporation of the liquid refrigerant can be promoted.

An electronic device according to one embodiment of the present invention includes a heat source and a heat transport device.
The heat source has an exterior part.
The heat transport device includes a heat receiving unit, a condensing unit, and an evaporating unit. The heat receiving part is for receiving heat from a heat source. The condensing unit is disposed to face the heat receiving unit in the first direction, and condenses the working fluid from a gas phase to a liquid phase. The evaporation section includes a plurality of evaporation structures disposed in at least one direction orthogonal to the first direction with a first flow section through which the working fluid can flow. The evaporating structure has a plurality of recesses that respectively open to face the first flow part at a plurality of different positions in the first direction. The concave portion has an inclined surface inclined in a direction including the component in the first direction.

  According to the heat transport device, the inclined surfaces are provided at a plurality of different positions in the first direction of the two evaporation structures adjacent to each other with the first flow part interposed therebetween. Thereby, in the several height range from which the liquid level of a working fluid differs, a liquid surface of an efficient shape can be ensured when evaporating a working fluid and moving it to a 1st distribution part. Thereby, an evaporation part can evaporate a working fluid efficiently. According to the above electronic device, the exterior part of the heat source is thermally connected to the heat transport device, so that the heat transport device can efficiently diffuse the heat of the heat source.

  As described above, according to the heat transport device of the present invention, heat transport can be stably performed regardless of the vertical fluctuation of the liquid level position of the working fluid.

It is a side view showing the state where the heat source was connected to the heat spreader concerning a 1st embodiment of the present invention. It is a top view which shows a heat spreader. It is a schematic sectional drawing which shows the heat spreader seen from the AA line cross section shown in FIG. It is a partial expanded sectional view which shows an evaporation part. It is a schematic diagram which shows distribution | circulation of the refrigerant | coolant in an evaporation part. It is another schematic diagram which shows distribution | circulation of the refrigerant | coolant in an evaporation part. It is another schematic diagram which shows distribution | circulation of the refrigerant | coolant in an evaporation part. It is a schematic diagram for demonstrating operation | movement of a heat spreader. It is a disassembled perspective view which shows a heat spreader. It is a schematic sectional drawing which shows the heat spreader which concerns on the 2nd Embodiment of this invention. It is a partial expanded sectional view which shows an evaporation part. It is a perspective view which shows the electronic device provided with the heat spreader.

Hereinafter, embodiments of the present invention will be described with reference to the drawings.
In each embodiment of the present invention, a heat spreader will be described as an example of the heat transport device.

<First Embodiment>
[Structure of heat spreader 1]
FIG. 1 is a side view showing a state in which a heat source is connected to the heat spreader 1 according to the first embodiment of the present invention. FIG. 2 is a plan view showing the heat spreader 1.

  As shown in these drawings, the heat spreader 1 has a container 2. The container 2 includes a heat receiving plate 4 and a heat radiating plate 3 that constitute two main surfaces facing each other. The heat receiving plate 4 and the heat radiating plate 3 are joined airtightly via the side wall 5. The container 2 is sealed with a refrigerant (working fluid).

  The heat sink 3, the heat receiving plate 4, and the side wall 5 are made of, for example, a metal material. For example, copper having a high thermal conductivity may be used as the metal material. Other examples of the metal material include, but are not limited to, stainless steel and aluminum. In addition to the metal material, a material having high thermal conductivity such as carbon may be used. All of the heat radiating plate 3, the heat receiving plate 4 and the side wall 5 may be made of different materials, or some of them may be made of the same material, or all of them may be made of the same material. Also good.

  A heat source 50 is thermally connected to the heat receiving plate 4, and the heat receiving plate 4 receives heat from the heat source 50. The term “thermally connected” includes not only direct connection but also connection through a heat conductor, for example. Examples of the heat source 50 include electronic devices such as a CPU (Central Processing Unit), resistors, other heat generating electronic components, and a display. Heat from the heat source 50 is transmitted to the heat spreader 1 through the heat receiving plate 4.

  A heat radiating member such as a heat sink 55 is thermally connected to the heat radiating plate 3. Heat is transmitted from the heat spreader 1 to the heat sink 55, and this heat is radiated from the heat sink 55.

  As the refrigerant sealed in the container 2, for example, a solution obtained by adding a small amount of an organic compound having a hydroxy group (OH group) to pure water may be used. Examples of the organic compound having a hydroxyl group include alcohols, diols, polyols, phenols and the like. More specifically, the organic compound having a hydroxyl group includes alcohols such as methanol, ethanol, propanol, butanol and hexanol, diols such as ethylene glycol and propylene glycol, polyols such as glycerin, and phenols such as phenol and alkylphenol. Etc.

  Alternatively, as the refrigerant, pure water may be used as it is without adding the above alcohols, or fluorocarbon, alternative fluorocarbon, fluorine, ammonia, acetone, or the like may be used. However, it is not limited to these.

  FIG. 3 is a schematic cross-sectional view showing the heat spreader 1 as seen from the cross section taken along line AA shown in FIG.

  As shown in the figure, the heat receiving plate 4 constitutes the heat receiving portion of the heat spreader 1, the heat receiving surface 41 corresponding to the outer wall surface of the container 2, and the evaporation surface facing the heat radiating plate 3 and facing the heat receiving surface 41. 42.

  The heat receiving surface 41 is a surface to which the heat source 50 is thermally connected. The heat receiving surface 41 may be provided with a highly thermally conductive solid layer (not shown) that can diffuse heat from the heat source 50 in the surface direction and better transfer the heat to the heat spreader 1. As the high thermal conductive solid layer, a carbon graphite layer, a diamond layer, or the like having a thermal conductivity of approximately 400 to 2000 WmK can be used. In addition to the single material described above, the high thermal conductive solid layer may be formed of a composite material, or may be configured by laminating a plurality of layers made of different materials.

  The evaporation surface 42 has a bonding region 43 bonded to the side wall 5 at the periphery. The evaporation surface 7 is provided on the evaporation surface 42. The evaporation unit 7 evaporates a liquid-phase refrigerant (hereinafter referred to as a liquid refrigerant). In this figure, in order to make the explanation easy to understand, the scale shape of the evaporating unit 7 with respect to the heat spreader 1 is increased and the actual shape is changed. Hereinafter, for the same purpose, the actual shape may be changed and drawn.

  The internal space of the container 2 mainly constitutes the distribution unit 6 (first distribution unit). The circulation part 6 is a flow path for liquid refrigerant and gas-phase refrigerant (hereinafter referred to as vapor refrigerant). That is, the circulation unit 6 circulates the liquid refrigerant from the heat radiating plate 3 side to the heat receiving plate 4 side by gravity and circulates the vapor refrigerant from the heat receiving plate 4 side to the heat radiating plate 3 side.

The heat radiating plate 3 constitutes a condensing part of the heat spreader 1, and has a heat radiating surface 31 corresponding to the outer wall surface of the container 2, and a condensing surface 32 facing the heat receiving plate 4 and facing the heat radiating surface 31.
The condensation surface 32 condenses the vapor refrigerant evaporated in the evaporation unit 7.
The heat radiating surface 31 is a surface to which a heat radiating member such as the heat sink 55 is thermally connected.

  In the present specification, the “heat receiving portion” does not refer only to the heat receiving surface 41 of the heat receiving plate 4 but may include a region near the heat receiving plate 4 in the internal space of the container 2. Similarly, the “condensing part” does not indicate only the condensing surface 32 of the heat radiating plate 3, but may include a region near the heat radiating plate 3 in the internal space of the container 2. In addition, the regions indicating the “heat receiving portion” and the “condensing portion” may be slightly shifted depending on the amount of heat of the heat source 50 or the like.

  The inner surface of the side wall 5 constitutes a liquid phase channel 51. The liquid phase flow channel 51 circulates the liquid refrigerant condensed on the condensation surface 32 of the heat radiating plate 3 from the heat radiating plate 3 side to the heat receiving plate 4 side by capillary force and gravity.

The heat spreader 1 of the present embodiment has a substantially square planar shape. The length e (see FIG. 2) of one side of the heat spreader 1 is, for example, about 30 to 50 mm. The heat spreader 1 has, for example, a substantially rectangular side surface. The height h (see FIG. 1) of the heat spreader 1 is, for example, about 2 to 5 mm. The size of the heat spreader 1 described above assumes that the heat source 50 thermally connected to the heat spreader 1 is a CPU used in a PC (Personal Computer). The size of the heat spreader 1 may be appropriately determined according to the heat source 50. For example, when the heat source 50 that is thermally connected to the heat spreader 1 is a large-capacity heat source such as a large display, e needs to be further increased, for example, about 2600 mm. The size of the heat spreader 1 is set to such a value that the cycle of evaporation and condensation of the refrigerant flowing in the container 2 is repeated without delay so that the refrigerant can flow and condense appropriately. The operating temperature range of the heat spreader 1 is assumed to be approximately −40 ° C. to + 200 ° C. The endothermic density of the heat spreader 1 is, for example, 8 W / mm ² or less.

  The container 2 may be designed as follows. The permeation heat transfer coefficient α viewed from the heat receiving surface 41 of the heat receiving plate 4 shows a very large value, and therefore it is desirable that sufficient heat is supplied into the heat receiving surface 41 in order to use this heat transfer effectively. It is an important factor in the structure of the container 2 to have an in-plane thermal conductivity λ with little change in the dimensionless Biot number Bi (Bi = αl / λ). Here, the representative length l is the maximum distance that the gas-phase refrigerant reaches from the center of the heat source 50 in the heat spreader 1. At this time, a typical value for the Bi number is about 0.1 to 10, and Bi <1 may be satisfied.

[Structure of the evaporation part 7]
FIG. 4 is a partial enlarged cross-sectional view showing the evaporation unit 7.
The evaporator 7 is provided in a region excluding the joint region 43 of the evaporation surface 42 of the heat receiving plate 4. The evaporation unit 7 is disposed in a direction (X-axis direction) orthogonal to the Z-axis direction (first direction) with a circulation unit 6 (first distribution unit) capable of circulating the refrigerant interposed therebetween. Evaporation structure 71 is provided. The plurality of evaporation structures 71 are arranged in a long shape parallel to each other along the Y-axis direction (second direction).

  The evaporating structure 71 has a plurality of elongate concave portions 74 extending in the Y-axis direction at a plurality of positions (heights) different from each other in the Z-axis direction.

Each of the plurality of recesses 74 is formed by a first surface 75 near the heat radiating plate 3, a second surface 76 near the heat receiving plate 4, a third surface 77, and an inclined surface 78 near the heat receiving plate 4. The
The first surface 75 and the second surface 76 are opposed to each other with a predetermined distance therebetween, and are each configured by a plane formed by the X axis and the Y axis, or a plane substantially along the plane.
The third surface 77 connects the first surface 75 and the second surface 76, and is configured by a plane formed by the Y axis and the Z axis or a plane substantially along this plane.
The inclined surface 78 is provided continuously from the second surface 76 and faces the first surface 75. The inclined surface 78 has an inclination that approaches the heat radiating plate 3 as the distance from the circulation portion 6 increases. More specifically, the angle is selected to a value that can form a meniscus surface having an efficient shape for evaporating the liquid refrigerant. The width of the opening of the recess 74 in the Z-axis direction is determined by one end of the inclined surface 78 near the flow portion 6 and one end of the first surface 75 near the flow portion 6.

  Here, the distance between the first surface 75 and the second surface 76 is selected to a value that can generate a capillary force. That is, the rectangular groove 62 for allowing the liquid refrigerant to flow in the Y-axis direction by capillary force by the second surface 76, the third surface 77, and a part of the first surface 75 facing the third surface 77. (Second distribution part) is formed. In addition, the width | variety of the Z-axis direction of the rectangular groove part 62 is about 10-500 micrometers, for example.

  The shape of the recess 74 is a common shape except for the uppermost recess 74 in the plurality of recesses 74 provided in the evaporation structure 71 at a plurality of different positions in the Z-axis direction. The uppermost recess 74 is formed by an inclined surface 78, a second surface 76, and a third surface 77, and the inclined surface 78, the second surface 76, and the third surface 77 are exposed to the circulation portion 6. ing. In addition, the inclined surface 78 of the lowermost recess 74 extends from one end of the inclined surface 78 of the upper recess 74 near the flow portion 6 with the same inclination angle, and the two evaporation structures 71 adjacent in the X-axis direction are extended. It reaches the center in the X-axis direction of the flow part 6 between. As a result, the lowermost V-groove 61a is formed by the lowermost inclined surface 78 of each of the two evaporation structures 71 adjacent in the X-axis direction. In addition, each end of the middle inclined surface 78 of each of the two evaporation structures 71 adjacent to each other in the X-axis direction is spaced apart with the circulation part 6 interposed therebetween. Therefore, the middle inclined surface 78 of each of the two evaporation structures 71 adjacent in the X-axis direction functions as a middle V-groove 61b integrally provided on the lowermost V-groove 61a. Similarly, one end of the uppermost inclined surface 78 of each of the two evaporation structures 71 adjacent to each other in the X-axis direction is also spaced apart with the circulation part 6 interposed therebetween, and is integrally formed on the middle V-groove part 61b. It functions as the uppermost V-groove 61c provided in the. As a result, three stages of V-grooves 61 a, 61 b, 61 c are provided integrally with each other via the rectangular groove 62 between two evaporation structures 71 adjacent in the X-axis direction.

  In addition, the width | variety of the X-axis direction of each V groove part 61a, 61b, 61c is about 10-1000 micrometers, for example.

  In this figure, the recess 74 is provided in three stages in the Z-axis direction. Here, the lowermost recess 74 is denoted by 74a, the uppermost recess 74 is denoted by 74c, and the middle recess 74 is denoted by 74b. Similarly, the portions related to the recesses 74a, 74b, and 74c may be denoted by reference numerals a, b, and c, respectively. Further, of the recesses 74a, 74b, and 74c, the same configuration is described with respect to any one recess 74, and in that case, referred to as “a recess 74”. Note that the number of the recesses 74 is not limited to three and may be provided in any number. Similarly, of the lowermost V-groove 61a, the middle V-groove 61b, and the uppermost V-groove 61c, the same V-groove 61 will be described for the same parts. 61 ".

[Distribution of refrigerant in evaporation section 7]
Next, circulation of the refrigerant in the evaporation unit 7 having the above configuration will be described.
Here, when the liquid refrigerant level in the evaporator 7 is located in the lowermost V groove 61a (FIG. 5), in the middle V groove 61b (FIG. 6), and in the uppermost V groove 61c. The circulation of the refrigerant in the evaporating unit 7 when located (FIG. 7) will be described with reference to each drawing.

FIG. 5 is a schematic view showing the circulation of the refrigerant in the evaporation unit 7.
With reference to the figure, the circulation of the refrigerant when the liquid refrigerant level in the evaporator 7 is located in the lowest V-groove 61a will be described. When the liquid level of the liquid refrigerant in the evaporation unit 7 is located in the lowest V-groove 61a, for example, when the heat density of the heat source 50 thermally connected to the heat receiving plate 4 is high, the liquid refrigerant evaporates. This is a case where the amount increases and the liquid level of the liquid refrigerant in the evaporation section 7 becomes low.

  When the liquid level of the liquid refrigerant is in the lowest V-groove 61a, the liquid level of the liquid refrigerant becomes a meniscus surface M due to surface tension. When the liquid surface becomes the meniscus surface M, a thin portion F of the liquid film is generated in the liquid refrigerant at a portion of the inclined surfaces 78a, 78a near the heat radiating plate 3. The heat generated by the heat source 50 thermally connected to the heat receiving plate 4 is transmitted to the evaporation structure 71, and is transmitted to the liquid refrigerant in the thin portion F of the liquid film via the inclined surfaces 78a and 78a. Since the liquid film is thin in this portion F, the liquid refrigerant quickly boils and evaporates due to the heat from the evaporation structure 71. The gas-phase refrigerant mainly evaporated from the thin portion F of the liquid film moves in the Z-axis direction through the flow part 6 between the adjacent evaporation structures 71 and 71 as indicated by arrows in the figure, and the heat radiating plate 3 side. Head to.

  When the liquid level is located in the lowermost V-groove 61a, the amount of liquid refrigerant in the evaporation unit 7 is small, so that the evaporation of the liquid refrigerant in the part located directly above the heat source 50 is the liquid refrigerant in the other part. The evaporation of the liquid refrigerant in the evaporating unit 7 may be locally promoted, such as being promoted by evaporation of the liquid. At this time, the liquid refrigerant decreases in the region where the evaporation of the liquid refrigerant is promoted. Since the liquid refrigerant is moved in the Y-axis direction by the capillary force in the V-groove 61a, the liquid refrigerant is supplemented from the surroundings in the area where the liquid refrigerant is reduced, and dryout due to a local decrease in the liquid refrigerant occurs. The risk of occurrence is reduced.

FIG. 6 is another schematic diagram showing the circulation of the refrigerant in the evaporation unit 7.
With reference to the same figure, the distribution | circulation of the refrigerant | coolant when the liquid level of the liquid refrigerant in the evaporation part 7 is located in the V-groove part 61b of a middle stage is demonstrated. The case where the level of the liquid refrigerant in the evaporation unit 7 is located in the middle V-groove 61b is, for example, that the heat density of the heat source 50 thermally connected to the heat receiving plate 4 is lower than the example shown in the previous figure. In some cases, the evaporation amount of the liquid refrigerant becomes small and the liquid level of the liquid refrigerant in the evaporation unit 7 rises.

  When the level of the liquid refrigerant is in the middle V-groove 61b, the liquid refrigerant has a meniscus surface M due to surface tension. When the liquid surface becomes the meniscus surface M, a thin portion F of the liquid film is generated in the liquid refrigerant at a portion of the inclined surfaces 78b, 78b near the heat radiating plate 3. The heat generated by the heat source 50 connected to the heat receiving plate 4 is transmitted to the evaporation structure 71 and is transmitted to the liquid refrigerant in the thin portion F of the liquid film through the inclined surfaces 78b and 78b. Since the liquid film is thin in this portion F, the liquid refrigerant quickly boils and evaporates due to the heat from the evaporation structure 71. The gas-phase refrigerant evaporated mainly from the thin part F of the liquid film moves in the Z-axis direction through the flow part 6 between the adjacent evaporation structures 71 and 71 as indicated by an arrow a in the figure, and the heat sink 3 Head to the side.

  When the liquid level reaches the vicinity of the top of the V-groove 61b, the liquid refrigerant is sucked into the rectangular groove 62b from the upper part of the V-groove 61b by the capillary force, and the state shown in FIG. 6 is obtained. In this state, the liquid refrigerant sucked up and restrained in the rectangular groove 62 b forms a liquid level facing the flow part 6. This liquid level becomes a meniscus surface M1 due to surface tension. The capillary radius of the meniscus surface M1 is smaller than the capillary radius of the meniscus surface M formed in the V groove 61b. Therefore, in the rectangular groove 62b, a larger capillary force is generated, and the movement of the liquid refrigerant in the Y-axis direction can be effectively assisted. Thereby, even if the liquid level position in the evaporation part 7 rises, the movement of the refrigerant in the Y-axis direction by the capillary force can be performed well, and the circulation of the liquid refrigerant can be performed well. .

  Here, when the evaporation of the liquid refrigerant in the evaporation unit 7 is locally promoted, the liquid refrigerant in the V-groove 61b decreases in the region where the evaporation of the liquid refrigerant is promoted. At this time, since the liquid refrigerant is moved in the Y-axis direction by the capillary force in the rectangular groove 62b, the liquid refrigerant is supplemented from the rectangular groove 62b in the region where the liquid refrigerant in the V-groove 61b is reduced. This reduces the risk of dryout due to a local decrease in the liquid refrigerant in the V-groove 61b.

  Further, since the liquid surface becomes the meniscus surface M1, the liquid refrigerant includes a portion of the second surface 76b near the inclined surface 78b and a portion of the first surface 75b opposite to the liquid surface and the liquid surface. Thus, a thin part F1 of the liquid film is generated. The heat generated by the heat source 50 is transmitted to the evaporation structure 71, and the thin portion F1 of the liquid film is passed through a part of the second surface 76b near the inclined surface 78b and a part of the first surface 75b opposite to the inclined surface 78b. It is transmitted to the liquid refrigerant. Since the liquid film is thin in the portion F1, the liquid refrigerant quickly boils and evaporates due to the heat from the evaporation structure 71. The gas-phase refrigerant mainly evaporated from the thin part F1 of the liquid film moves in the Z-axis direction through the flow part 6 between the adjacent evaporation structures 71 and 71 as indicated by an arrow b in the figure, and the heat sink 3 Head to the side.

  In addition, although illustration is abbreviate | omitted, with the change of the quantity of a liquid refrigerant, a meniscus surface may arise in the rectangular groove part 62a of the lowest step, and a liquid refrigerant may be moved to the Y-axis direction by the capillary force in the rectangular groove part 62a. . In addition, a meniscus surface may be formed in the uppermost rectangular groove 62c constituted by the second surface 76c and the third surface 77c, and the liquid refrigerant may be moved in the Y-axis direction by capillary force in the rectangular groove 62c. . Also in these cases, since the liquid refrigerant is moved in the Y-axis direction by the capillary force in the rectangular groove portion 62, the liquid refrigerant is supplemented from the rectangular groove portion 62 in the region where the liquid refrigerant in the V groove portion 61 is reduced. According to this configuration, since the rectangular groove portions capable of forming a meniscus surface having an efficient shape for generating a large capillary force are provided in a plurality of stages, the liquid-phase working fluid can be formed regardless of the position of the liquid surface. Distribution in the Y-axis direction by capillary force can be promoted.

FIG. 7 is still another schematic diagram illustrating the circulation of the refrigerant in the evaporation unit 7.
With reference to the same figure, the distribution | circulation of the refrigerant | coolant in case the liquid level of the liquid refrigerant in the evaporation part 7 is located in the uppermost V groove part 61c is demonstrated. The case where the liquid refrigerant level in the evaporator 7 is located in the uppermost V-groove 61c means, for example, that the heat density of the heat source 50 thermally connected to the heat receiving plate 4 is further higher than in the example shown in the previous figure. When the temperature is low, the evaporation amount of the liquid refrigerant is further reduced and the liquid level of the liquid refrigerant in the evaporation unit 7 is increased.

  When the liquid level of the liquid refrigerant is in the uppermost V-groove 61c, the liquid level of the liquid refrigerant becomes a meniscus surface M due to surface tension. When the liquid surface becomes the meniscus surface M, a thin portion F of the liquid film is generated in the liquid refrigerant at a portion of the inclined surfaces 78c, 78c near the heat radiating plate 3. The heat generated by the heat source 50 connected to the heat receiving plate 4 is transmitted to the evaporation structure 71 and is transmitted to the portion F of the liquid refrigerant through the inclined surfaces 78c and 78c. Since the liquid film is thin in this portion F, the liquid refrigerant quickly boils and evaporates due to the heat from the evaporation structure 71.

  As described above, according to the present embodiment, the evaporation section 7 has a configuration in which a plurality of stages of V-groove parts 61 and rectangular groove parts 62 are alternately and integrally provided.

  Since a plurality of stages of V-grooves 61 are provided integrally, a meniscus surface having an efficient shape for evaporating the liquid refrigerant and distributing it to the heat radiating plate 3 in a plurality of height ranges with different liquid refrigerant levels. M can be secured.

  In general, in order to efficiently evaporate the liquid refrigerant in the groove, it is only necessary to enlarge the thin part of the liquid refrigerant liquid film formed between the inclined surface of the V groove and the liquid refrigerant liquid surface. The inclination angle of the inclined surface of the V-groove is preferably gentle. However, if the inclination angle of the inclined surface of a general V-groove is made gentle, the width of the V-groove in the X-axis direction becomes large and a sufficient capillary force cannot be obtained, and the Y of the V-groove of the liquid refrigerant is not obtained. The movement in the axial direction is delayed.

  On the other hand, according to the present embodiment, a plurality of V-groove portions 61 are integrally provided, so that the gradient of the inclined surface 78 of each of the plurality of V-groove portions 61 can be selected with a high degree of freedom, and is gentle. An inclined slope can be realized. Thereby, it is possible to improve the evaporation amount of the liquid refrigerant in each of the plurality of V groove portions 61. Therefore, according to this evaporation part 7, regardless of the height of the liquid refrigerant, a high evaporation action can be stably produced.

  In addition, since the plurality of rectangular grooves 62 are integrally provided, the meniscus having an efficient shape for moving the liquid refrigerant in the Y-axis direction by capillary force in a plurality of height ranges having different liquid levels of the liquid refrigerant. The surface M1 can be secured. Thereby, a large capillary force is generated in each of the rectangular groove portions 62 provided in a plurality of stages, and the movement of the liquid refrigerant in the Y-axis direction can be effectively assisted. Therefore, according to the evaporation unit 7, a large capillary force can be stably generated regardless of the liquid level of the liquid refrigerant.

  Further, since the plurality of V-groove parts 61 and the rectangular groove parts 62 are alternately and integrally provided, the liquid refrigerant that has moved in the Y-axis direction by the capillary force in the rectangular groove part 62 is located at the liquid surface position in the V-groove part 61. Is compensated for the lowered part. More specifically, when the liquid level position of the liquid refrigerant stored in the V-groove 61 is biased, the liquid refrigerant passes through the rectangular groove 62 positioned above the V-groove 61 by the capillary force in the Y-axis direction. This liquid refrigerant is supplemented by the portion where the liquid level position in the V-groove 61 is lowered. Therefore, according to this evaporation unit 7, the liquid level position of the liquid refrigerant in the evaporation unit 7 can be kept uniform regardless of the liquid level of the liquid refrigerant, and the heat transport by the heat spreader 1 can be stably performed. Can be done.

  In order to further promote evaporation, a material having high thermal conductivity may be provided on the surface of the evaporation structure 71, for example, the surfaces of the inclined surfaces 78 and 78, if necessary. For example, carbon nanotubes can be used as the material having high thermal conductivity. Since the carbon nanotube has a nanoscale structure on the surface, the contact area of the liquid refrigerant can be increased, and evaporation of the liquid refrigerant can be promoted. Since carbon nanotubes have super water repellency, when pure water or the like is used as the refrigerant, the liquid refrigerant may not produce sufficient wettability with respect to the carbon nanotubes. Therefore, depending on the composition of the refrigerant to be used, it is desirable to perform an improvement treatment for enhancing the wettability on the surface of the carbon nanotube. An example of the surface improvement treatment includes introduction of a hydrophilic group such as a carboxyl group by ultraviolet treatment. Thereby, the wettability of the carbon nanotube surface is improved, and the evaporation of the liquid refrigerant can be further improved.

[Operation of heat spreader]
FIG. 8 is a schematic diagram for explaining the operation of the heat spreader 1.
As shown in the figure, when the heat source 50 generates heat, the heat receiving surface 41 of the heat receiving plate 4 receives this heat. If it does so, a liquid refrigerant will distribute | circulate by capillary force as mentioned above mainly in the inclined surfaces 78 and 78 of the evaporation part 7 provided in the evaporation surface 42 of the heat receiving plate 4 (arrow A). The liquid refrigerant is heated and evaporated in the evaporating unit 7 and becomes a vapor refrigerant. The vapor refrigerant circulates through the circulation part 6 so as to go toward the heat radiating plate 3 (arrow B). As the vapor refrigerant circulates through the circulation part 6, heat is diffused, and the vapor refrigerant is condensed on the condensation surface 32 of the heat radiating plate 3 and returns to the liquid phase (arrow C). Thereby, the heat diffused by the heat spreader 1 is transmitted from the heat radiating surface 31 of the heat radiating plate 3 to the heat sink 55 and radiated from the heat sink 55 (arrow D). The liquid refrigerant flows through the liquid phase flow path 51 by capillary force or flows through the flow part 6 by gravity and returns to the evaporation part 7 (arrow E). By repeating such an operation, the heat of the heat source 50 is moved by the heat spreader 1.

  The area of each operation indicated by arrows A to E indicates a certain standard or reference. Since each of these operation regions may be slightly shifted depending on the amount of heat of the heat source 50 or the like, each operation is not clearly divided for each region.

[Method of manufacturing heat spreader 1]
Next, a method for manufacturing the heat spreader 1 will be described.
FIG. 9 is an exploded perspective view showing the heat spreader 1.
The heat spreader 1 is formed by laminating a plurality of plate members 4, 8a, 9a, 8b, 9b, 8c, 10, 3 and bonding them together.

  First, a plurality of long V-shaped groove portions 61a parallel to each other are formed by cutting or etching or the like in a region excluding the joining region 43 of the evaporation surface 42 of the heat receiving plate 4. A rib 45 is provided between the adjacent V groove portions 61a. The surface where the plurality of ribs 45 are opposed to each other with the V-groove 61a interposed therebetween is a surface constituting the inclined surface 78a of the evaporation structure 71.

  A through-groove having a trapezoidal cross section is formed in the plate material, and a plurality of first plate materials 9 (9a, 9b) constituting the first surface 75, the second surface 76, and the inclined surface 78 of the evaporation structure 71 are produced. . The main surfaces of the first plate 9 that face each other are the surfaces constituting the first surface 75 and the second surface 76 of the evaporation structure 71. In the first plate member 9, a plurality of through-holes 92 having a long trapezoidal cross section are formed in parallel to each other in a region excluding the bonding region 91 that is a peripheral portion by cutting or etching. Ribs 93 are provided between the adjacent through grooves 92. The side surfaces of the plurality of ribs 93 facing each other across the through grooves 92 are surfaces that constitute the inclined surface 78 of the evaporation structure 71 and are inclined with respect to the main surface of the first plate member 9.

  Here, the height of the V-groove 61 in the Z-axis direction is determined by the thickness of the first plate member 9, the gradient of the V-groove 61 is determined by the gradient of the side surface of the rib 93, and the width of the through-groove 92 determines the V-groove 61. The width in the X-axis direction is determined. Therefore, the thickness of the first plate member 9 and the gradient of the side surface of the rib 93 are selected to values suitable for evaporating the liquid refrigerant. The width of the through groove 92 is selected to a value that allows the liquid refrigerant to flow through the V groove portion 61 efficiently.

  A plurality of second plate members 8 (8a, 8b, 8c) constituting the third surface 77 of the evaporation structure 71 are formed by forming a through groove having a rectangular cross section in the plate member. In the second plate member 8, a plurality of long through-grooves 82 having a rectangular cross section are formed in parallel to each other in a region excluding the bonding region 81 that is a peripheral portion by cutting or etching. Ribs 83 are provided between adjacent through grooves 82. The surfaces of the adjacent ribs 83 facing each other across the through groove 82 are parallel to each other, and this surface is a surface constituting the third surface 77 of the evaporation structure 71.

  Here, since the width of the rectangular groove 62 in the Z-axis direction is determined by the thickness of the second plate member 8, the thickness of the second plate member 8 is selected to a value suitable for moving the liquid refrigerant by capillary force. Is done.

  Subsequently, these plate members 4, 8 (8a, 8b, 8c), 9 (9a, 9b) are replaced with the heat receiving plate 4, the second plate member 8a, the first plate member 9a, the second plate member 8b, and the first plate member. 9b and the second plate 8c are stacked in this order. Here, the plate members 4, 8 a, 9 a, 8 b, 9 b, 8 c have a plurality of ribs 45, 83, 93 arranged in the Y-axis direction, and are joined regions 43, 81, 91 and a plurality of ribs 45, 83, 93. Are stacked so as to contact each other in the Z-axis direction.

  The laminated joining regions 43, 81, 91 constitute a part of the side wall 5 of the container 2, and the plural laminated ribs 45, 83, 93 constitute an evaporation structure 71 of the evaporation unit 7. The V-groove 61a and the through-grooves 82 and 92 between the two adjacent ribs 45, 83, and 93 are three-stage V-grooves that are integrally provided between the two evaporation structures 71 that are adjacent in the X-axis direction. 61a, 61b and 61c are configured.

  Heat is radiated to the joining region 81 of the second plate member 8c located on the uppermost surface of the stacked plate members 4, 8a, 9a, 8b, 9b, 8c through the frame-like plate member 10 constituting a part of the side wall 5. The plate 3 is laminated. In addition, this frame-shaped board | plate material 10 is not limited to what was formed integrally, It is good also as what consists of four flat plate-shaped board | plate materials.

  These laminated plate members 4, 8a, 9a, 8b, 9b, 8c, 10, 3 are joined. At the time of joining, precise positioning of each member is performed. Thereby, the container 2 which has the evaporation part 7 inside is formed.

  Subsequently, a refrigerant is injected into the formed container 2 and sealed. An inlet and an injection path (not shown) for injecting the refrigerant are provided in the heat receiving plate 4, for example, and the inside of the container 2 is depressurized through these inlet and the injection path, and the refrigerant is injected into the container 2. Is done. The container 2 into which the refrigerant has been injected is sealed, and the heat spreader 1 is completed.

  As described above, in order to set the gradient and dimensions of the V groove 61 of the evaporation unit 7 to values suitable for evaporating the liquid refrigerant, the thickness of the first plate 9 and the ribs 93 and the through grooves to be formed are formed. The size of 92 may be adjusted. Therefore, the slope of the inclined surface of the V groove 61 can be selected with a high degree of freedom. Moreover, what is necessary is just to adjust the thickness of the 2nd board | plate material 8, in order to make the groove width of the rectangular groove part 62 into a value suitable for moving a liquid refrigerant by capillary force. Therefore, the groove width of the rectangular groove 62 can be selected with a high degree of freedom. As mentioned above, according to the manufacturing method of the heat spreader 1 of this embodiment, the heat spreader 1 which can perform efficient heat transport can be manufactured easily.

  In addition, the manufacturing method of the heat spreader 1 is not limited to the above. For example, the heat spreader 1 may be manufactured as follows. The side wall 5 is joined to the joining region 43 of the heat receiving plate 4. A plurality of evaporating structures 71 are manufactured by laminating and joining a plurality of plate materials in which a plurality of through grooves are formed in parallel to each other by cutting or etching on the evaporation surface 42 of the heat receiving plate 4 to which the side walls 5 are bonded. To do. Each of the plurality of plate members has a size in plan view that is equal to or slightly smaller than the size of the region excluding the joining region 43 of the heat receiving plate 4. The heat radiating plate 3 is joined to a portion of the side wall 5 on the side facing the heat receiving plate 4, whereby the container 2 having the evaporation portion 7 inside is produced.

<Second Embodiment>
[Structure of heat spreader 11]
FIG. 10 is a schematic sectional view showing a heat spreader 11 according to the second embodiment of the present invention.
In the following description, the same components and functions of the heat spreader 1 according to the first embodiment will be given the same reference numerals, and the description will be simplified or omitted, and different points will be mainly described.

  The heat spreader 11 has a container 12. The container 12 includes a heat receiving plate 14, a heat radiating plate 13 provided to face the heat receiving plate 14, and a side wall 15 that joins the heat receiving plate 14 and the heat radiating plate 13 in an airtight manner. The container 12 is sealed with a refrigerant. The internal space of the container 12 mainly constitutes the refrigerant circulation portion 16.

  The heat receiving plate 14 has a heat receiving surface 141, an evaporation surface 142, and a bonding region 143. A heat source is thermally connected to the heat receiving surface 141. An evaporation unit 17 is provided on the evaporation surface 142.

  The heat radiating plate 13 has a heat radiating surface 131 and a condensing surface 132. A heat radiating member such as a heat sink is thermally connected to the heat radiating surface 131. The inner surface of the side wall 15 constitutes a liquid phase channel 151.

[Structure of the evaporation part 17]
FIG. 11 is a partial enlarged cross-sectional view showing the evaporation unit 17.
As shown in the figure, the evaporation unit 17 is provided in a region excluding the bonding region 143 of the evaporation surface 142 of the heat receiving plate 14. The evaporating unit 17 includes a plurality of evaporating structures 171 disposed in the X-axis direction with a circulation unit 16 (first circulation unit) through which the refrigerant can circulate. The plurality of evaporation structures 171 are arranged in a long shape parallel to each other with an interval of about several tens to 500 μm along the Y-axis direction.

  The evaporation structure 171 is made of a porous material, for example, a porous material in which a nanomaterial is bonded. As a porous material, for example, metals such as copper, stainless steel and aluminum, inorganic ceramics such as alumina and silica, zeolites, polymers such as acrylic resins, and composite resins obtained by kneading carbon nanotubes and carbon fibers into metals and polymers Can be used. This porous material has a large number of fine holes, and the average pore diameter is, for example, about 1 to 500 μm.

  The evaporation structure 171 has a large number of fine holes 174 that are opened at a plurality of different positions in the Z-axis direction. In this figure, in order to make the explanation easy to understand, the scale ratio of the fine holes 174 with respect to the evaporation structure 171 is increased and the number of the fine holes 174 is reduced, and the actual shape is changed.

  These many fine holes 174 are inclined at various gradients in various directions. Among the many small holes 174, there is a small hole 174a having an inclined surface 178 on the inner surface that is inclined in a direction including a component in the X-axis direction and a component in the Z-axis direction. At least the inner surface of the narrow hole 174a near the heat receiving plate 14 is an inclined surface 178 that is inclined so that the direction from the position away from the opening toward the circulation portion 16 is from the heat radiating plate 13 side to the heat receiving plate 14 side. . In addition, the multiple small holes 174 communicate with each other in the evaporation structure 171 in various directions.

  The liquid refrigerant is filled in the groove 161 formed by the adjacent evaporation structures 171 and 171 in the circulation part 16. The liquid surface of the liquid refrigerant forms a meniscus surface M between the evaporation structures 171 and 171. Note that the groove 161 may be V-shaped, rectangular, trapezoidal, or the like.

  When the liquid level is located in the vicinity of the narrow hole 174a, the liquid refrigerant wets and spreads on the inclined surface 178 on the inner surface of the narrow hole 174a. Thereby, a thin portion F of the liquid film is generated in the liquid refrigerant on the inclined surface 178. The heat generated by the heat source 50 connected to the heat receiving plate 14 is transmitted to the evaporation structure 171 and is transmitted to the liquid refrigerant through the inclined surface 178. In the thin part F of the liquid film, since the distance between the inclined surface 178 and the liquid surface as the evaporation surface is short, boiling and evaporation of the liquid refrigerant are promoted.

  The gas-phase refrigerant evaporated mainly from the thin part F of the liquid film moves in the Z-axis direction through the circulation part 16 between the adjacent evaporation structures 171 and 171 and moves toward the heat radiating plate 13.

  On the other hand, in the upper part of the inclined surface 178a, the liquid refrigerant is sucked up by the capillary force and restrained by the wall surface separated from the opening of the narrow hole 174a, and the liquid refrigerant can be moved by the capillary force here. 162 (second distribution section) is generated. The liquid refrigerant liquid level in the evaporating structure internal circulation part 162 faces the circulation part 16, for example, and becomes a meniscus surface M1 due to surface tension. The capillary radius of the meniscus surface M1 is smaller than the capillary radius of the meniscus surface M formed in the groove 161. Therefore, in the evaporating structure internal circulation part 162, a larger capillary force is generated, and the movement of the liquid refrigerant in various directions, for example, the Y-axis direction, can be effectively assisted. Thereby, even when the liquid surface position in the evaporation unit 7 is raised, the refrigerant can be moved in various directions, for example, in the Y-axis direction by the capillary force, and the liquid refrigerant can be circulated well. Can be done.

  According to this embodiment, in a plurality of height ranges where the liquid level of the liquid refrigerant is different, the liquid film is efficient in evaporating the liquid refrigerant on the inclined surface 178 of the narrow hole 174a and allowing it to flow to the flow part 16. The thin portion F can be ensured, and an efficient evaporating action can be produced regardless of the position of the liquid refrigerant. In addition, the meniscus surface M1 having an efficient shape for moving the liquid refrigerant in various directions by the capillary force can be secured in the evaporating structure in-body flow section 162, and the liquid level of the liquid refrigerant is related to the height of the liquid refrigerant. Therefore, a large capillary force can be stably generated.

  Similarly to the heat spreader 1, the heat spreader 11 according to the present embodiment repeats the phase change between the evaporator 17 and the heat radiating plate 13 where the liquid refrigerant is provided on the heat receiving plate 14. Thereby, the heat of the heat source 50 can be moved by the heat spreader 11.

  In addition, as a manufacturing method of the evaporation part 17, the block-shaped porous material which comprises the evaporation part 17 should be prepared, and the groove part 161 mutually parallel may be formed in this porous material by cutting or an etching.

  Alternatively, the plurality of through-grooves constituting the groove 161 are formed in the plurality of plate-like porous materials constituting the evaporation part 17 by cutting or etching. A plurality of evaporation structures 171 are obtained by laminating and bonding the plurality of plate-like porous materials to each other.

  Alternatively, a solid material having no porous structure may be used as the material of the evaporation unit 17. Concavities and convexities constituting the groove 161 and the evaporation structure 171 are formed on the block-shaped solid material constituting the evaporation portion 17 by cutting or etching. A narrow hole 174 having a predetermined depth is randomly formed in the solid material formed in the unevenness by etching or the like. Thereby, a plurality of evaporation structures 171 having a large number of fine holes 174 are obtained.

  As described above, according to the evaporation unit 17, the liquid refrigerant is evaporated in a plurality of height ranges having different liquid levels by the narrow holes originally formed in the porous material or randomly formed thin holes, and the circulation unit 16. It is possible to secure a thin portion F of the liquid film that is efficient when it is circulated. Therefore, according to this embodiment, the evaporation part 17 which can produce an efficient evaporation effect | action irrespective of the position of the liquid level of a liquid refrigerant can be produced easily.

[Electronics]
FIG. 12 is a perspective view showing a desktop PC 120 as an electronic apparatus including the heat spreader 1 (11).

  A circuit board 122 is disposed in the housing 121 of the PC 120. For example, a CPU 123 as a heat source is mounted on the circuit board 122. The heat spreader 1 (11) is thermally connected to the exterior portion of the CPU 23, and a heat sink is thermally connected to the heat spreader 1 (11).

  The embodiment according to the present invention is not limited to the above-described embodiment, and various other embodiments are conceivable.

  For example, the heat spreader 1 of the first embodiment may be made of a plate-like porous material or a plate material in which fine holes are randomly formed as shown in the second embodiment.

  Although the heat spreader has been described as an example of the heat transport device, the present invention is not limited to this, and a heat transport device such as a heat pipe or CPL (Capillary Pumped Loop) may be used.

  The planar shape of the heat spreader 1 (11) was a quadrangle. However, the planar shape may be circular, elliptical, polygonal, or any other shape.

  A desktop PC is taken as an example of electronic equipment. However, the present invention is not limited to this, and electronic devices include notebook PCs, PDAs (Personal Digital Assistance), electronic dictionaries, cameras, display devices, audio / visual devices, projectors, mobile phones, game devices, robot devices, and other electrifications. Products and the like.

DESCRIPTION OF SYMBOLS 1, 11 ... Heat spreader 2, 12 ... Container 3, 13 ... Radiating plate 4, 14 ... Heat receiving plate 5, 15 ... Side wall 6, 16 ... Distribution part (1st distribution part)
61, 61a, 61b, 61c ... V-groove 62, 62a, 62b, 62c ... Rectangular groove (second flow section)
7, 17 ... Evaporating part 71, 171 ... Evaporating structure 74, 74a, 74b, 74c ... Recess 75 ... First surface 76 ... Second surface 77 ... Third surface 78, 78a, 78b, 78c, 178 ... Inclined surface 161... Groove portion 162... Evaporative structure internal circulation portion 174 and 174a.

Claims (7)

A heat receiving part for receiving heat from the heat source;
A condensing part that is arranged to face the heat receiving part in the first direction and condenses the working fluid from the gas phase to the liquid phase;
An evaporation section provided in the heat receiving section and evaporating the working fluid from a liquid phase to a gas phase;
The evaporating part has a plurality of evaporating structures disposed in at least one direction orthogonal to the first direction with the first flow part through which the working fluid can flow.
The evaporating structure has inclined surfaces that open at a plurality of different positions in the first direction so as to face the first circulation part and are inclined in a direction including the component of the first direction inside. A heat transport device having a plurality of recesses. The heat transport device according to claim 1,
The plurality of evaporating structures are provided in a long shape along a second direction orthogonal to the first direction and the arrangement direction of the plurality of evaporating structures. The heat transport device according to claim 2,
The inclined surface is provided in a portion near the heat receiving portion on the inner surface of the concave portion so that a V-groove portion is formed between two adjacent evaporation structures across the first flow portion. apparatus. The heat transport device according to claim 3,
The concave portion includes a second circulation portion that moves the liquid-phase working fluid in a second direction by a capillary force at a position spaced from the opening with the inclined surface interposed therebetween. The heat transport device according to any one of claims 1 to 4,
The evaporation structure is a heat transport device made of a porous material. The heat transport device according to any one of claims 1 to 5,
A heat transport device in which carbon nanotubes are generated on the surface of the evaporation structure. A heat source having an exterior part;
A heat transport device provided in the exterior portion of the heat source,
The heat transport device includes a heat receiving unit for receiving heat from a heat source, a condensing unit that is disposed to face the heat receiving unit in a first direction, and that condenses the working fluid from a gas phase to a liquid phase, and the heat receiving unit. And an evaporation section that evaporates the working fluid from a liquid phase to a gas phase, and the evaporation section is capable of circulating the working fluid in at least one direction orthogonal to the first direction. A plurality of evaporating structures disposed across the first flow part, the evaporating structures opening at a plurality of different positions in the first direction facing the first flow part; And an electronic apparatus having a plurality of recesses having an inclined surface inclined in a direction including the component in the first direction.

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