WO2012154148A2

WO2012154148A2 - Heat transporting unit and electronic device

Info

Publication number: WO2012154148A2
Application number: PCT/US2011/021526
Authority: WO
Inventors: Susumu Ueda; Kei Mizuta
Original assignee: Molex Japan Co., Ltd.
Priority date: 2010-01-18
Filing date: 2011-01-18
Publication date: 2012-11-15
Also published as: JP2011145044A; TW201202649A; JP5413735B2; CN202889855U; WO2012154148A3

Abstract

A heat transporting unit comprises an upper plate, a lower plate that faces the upper plate, an interior space fillable with a coolant, formed by the upper plate and the lower plate, a vapor diffusing space for diffusing vaporized coolant, included within the interior space, a coolant return flow space for causing the condensed coolant to flow back, and an interference-preventing plate for preventing interference between the vaporized coolant diffusing in the vapor diffusing space and the condensed coolant flowing back in the coolant return flow space, wherein the interference-preventing plate has a plurality of pores for moving, to the coolant return flow space, coolant condensed in the vapor diffusing space, where the area of opening of the pores on the vapor diffusing space side is smaller than the area of opening on the coolant return flow space side.

Description

HEAT TRANSPORTING UNIT AND ELECTRONIC DEVICE

REFERENCE TO RELATED APPLICATIONS

[0001] The Present Application claims priority to Japanese Patent Application No. 2010-008599, entitled "Heat Transporting Unit And Electronic Device," filed on 18 January 2010 with the Japanese Patent Office, the contents of which is fully incorporated in its entirety herein.

BACKGROUND OF THE PRESENT APPLICATION

[0002] The Present Application relates generally to a heat transporting unit, and, in particular, to a heat transporting unit in an electronic device, able to transport efficiently heat received from a heat-producing body.

[0003] Electrical components such as semiconductor integrated circuit, LED elements, and power devices, are used in electrical equipment, industrial equipment, automobiles, and the like. These electrical components are heat-producing bodies that generate heat through the electric currents that flow therein. When the heat produced by these heat-producing bodies causes the temperature to rise above a certain point, then there are problems in that the operations cannot be guaranteed, along with the possibility of an adverse effect on other components and the frame, resulting in the possibility of causing reduced performance in the electronic equipment or industrial equipment itself.

[0004] A cooling device that uses heat pipes, having a cooling effect through vaporization and condensation of a coolant filled therein, has been proposed in order to cool these types of heat- producing bodies.

[0005] Heat pipes remove heat from the heat-producing bodies when the coolant filled therein is vaporized. The coolant that has been vaporized cools and condenses through the radiation of heat, and the condensed coolant is then circulated again. The heat pipe cools the heat-producing bodies through repetitive vaporization and condensation. That is, the heat pipes diffuse and transport heat. Moreover, through combination with a heat radiating member, or the like, the heat type cools the diffused or transported heat. When compared with a heat diffusing member made out of metal, the heat pipe diffuses or transports more heat effectively through the use of the coolant. [0006] In recent years, often the electronic component that is subject to cooling is an extremely small electronic component, such as a high-intensity light-emitting diode (LED), instead of just the relatively large semiconductor integrated circuits such as central processing units (CPUs) and dedicated ICs. This type of small electronic component is not only small in size as an individual component, but often is in a set of a plurality of electronic components. Because of this, the cooling device that uses the heat pipe often must cool a plurality of small electronic components.

[0007] Often small electronic components of this type are mounted gathered together on one portion of an electronic substrate, and often there is little spatial margin at the location of the mounting, and, in such a case, often heat radiation or exhaust is not possible. Because of this, there is a need for high-speed transport of heat in a specific direction after removing the heat from the electronic component, and the need for cooling at the transport destination. That is, there is the need for a heat transporting member, for transporting heat at a high speed in a specific direction, where the heat transporting member uses vaporization and return flow of a coolant.

[0008] In this type of situation, there is a proposal for a heat pipe that transports, in a specific direction, heat that is removed from a heat-producing body. See, for example, Japanese Patent Application Publication Nos. HI 1-101585 and 2002-039693.

[0009] In a cooling device that uses a heat pipe, improvements in the heat transporting efficiency (determined by the speed for a single cycle of diffusion of the vaporization coolant and the return flow of the coolant, and by the number of cycles in a unit time interval) are critical in increasing the cooling capability.

[0010] In a typical heat pipe, the coolant that is vaporized in the heat absorbing part, arrives at a heat radiating part through a pressure difference, and the coolant has arrived at the heat radiating part condenses through cooling at the heat radiating part, and flows back towards the heat absorbing part, through capillary forces, along capillary flow paths that are formed as wicks. At this time, the diffusion of the vaporized coolant and the return flow of the condensed coolant are in mutually opposite directions.

[0011] Shearing stresses are produced through the speed differentials between the diffusion of the vaporized coolant and the return flow of the condensed coolant in these mutually opposing directions. These shearing stresses are larger the greater the difference in speed between the vaporized coolant and the condensed coolant. Because of this, the shearing stresses on the condensed coolant are higher the greater the amount of heat absorbed and the greater the diffusion speed of the vaporized coolant, interfering with the return flow of the condensed coolant. The result is a reduction in the heat transporting cycling in the heat pipe.

[0012] The heat pipe disclosed in the '585 Reference discloses a plate-type heat pipe wherein there is an array of pores (which are more passageways than pores). In the heat pipe disclosed in the '585 Reference, each individual passageway performs the diffusion of the vaporized coolant and the return flow of the condensed coolant. The heat pipe disclosed in the '585 Reference is able to park transport heat towards a particular direction through these pores. That is, vaporized coolant diffuses from a first end portion of the pores to a second end portion thereof, and the condensed coolant flows back from the second end portion to the first end portion.

[0013] However, in the heat pipe disclosed in the '585 Reference, not only does the vaporized coolant flow back through pores that are passageways, but the condensed coolant flows back through the pores that are the passageways as well. Because of this, the coolant that is a gas and the coolant that is a liquid collided and interfere within the pores, reducing the transport cycling of the coolant. The result is that the heat pipe disclosed in the '585 Reference is unable to transport heat in the specific direction at a high speed.

[0014] Additionally, the heat pipe disclosed in the '693 Reference forms a diffusing path for the vaporized coolant and a return flow path for the condensed coolant through mutually-offsetted slits provided in a multilayer member. Because these slits are formed in a particular direction, the diffusion and return flow of the coolant are in a specific direction. As a result, the heat pipe disclosed in the '693 Reference can transport heat in a specific direction.

[0015] However, in the heat pipe disclosed in the '693 Reference, the vapor diffusing path for the diffusion of the vaporized coolant and the coolant return flow path for the return flow of the condensed coolant partially overlap along the specific direction. In this overlapping region, the vaporized coolant and the condensed coolant collide or interfere, reducing the transport cycling of the coolant. As a result, the heat pipe disclosed in the '693 Reference is unable to transport heat at a high speed in a specific direction. This is because the diffusion of the vaporized coolant from a first end portion to a second and portion of the heat pipe and the return flow of the condensed coolant from the second end portion to the first end portion interfere with each other. [0016] As described above, heat pipes in the conventional technology have a problem in that there is interference between the vaporized coolant and the condensed coolant, preventing the high-speed transport of heat in a specific direction.

[0017] Of course, in a heat pipe wherein it is necessary to vaporize and condense the coolant, the diffusing path for the vaporized coolant and the return flow path for the condensed coolant cannot be separated perfectly.

[0018] That is, in order to transport, at a high speed in a specific direction, heat that is removed from a heat-producing body, it is necessary to satisfy simultaneously (1) both of the coolants being able to move back and forth, with the coolant that condenses in the vapor diffusing path moving to the coolant return flow path and coolant in the coolant return path able to vaporize and move to the vapor diffusing path; and (2) the diffusion of the vaporized coolant and the return flow of the condensed coolant not interfering with each other.

SUMMARY OF THE PRESENT APPLICATION

[0019] The object of the Present Application is to provide a heat transporting unit able to transport, in a specific direction and at a high speed, heat from a heat-producing body, which, in contemplation of the issues described above, satisfies both (1) and (2). Note that the heat transporting unit has a sealed heat pipe structure that uses vaporization and condensation of a coolant.

[0020] In contemplation of the problem set forth above, the thermal transporting unit according to the Present Application comprises: an upper plate; a lower plate that faces the upper plate; a coolant-fillable interior space, formed by the upper plate and the lower plate; a vapor diffusing space for diffusing a vaporized coolant, included within the interior space; a coolant return flow space for the return flow of condensed coolant, provided in the interior space; and an

interference-preventing plate that prevents interference between the vaporized coolant that diffuses in the vapor diffusing space and the condensed coolant that flows back in the coolant return flow space; wherein: the interference-preventing plate has a plurality of pores that cause the condensed coolant in the vapor diffusing space to move into the coolant return flow space; wherein: the area of opening of the vapor diffusing space side in a pore is smaller than the area of opening on the coolant return flow space side. [0021] The heat transporting unit according to the Present Application can transport, in a single direction, at a high speed, and efficiently, heat that is removed from a heat-producing body.

[0022] In the heat transporting unit, the vapor diffusing space wherein the vaporized coolant diffuses, and the coolant return flow space, wherein the condensed vapor flows back, are separated by an interference-preventing plate, and because the vaporized coolant diffuses in the vapor diffusing space and the condensed coolant flows back in the coolant return flow space, each moves at a high speed.

[0023] In the interference-preventing plate, the coolant that condenses in the vapor diffusing space is caused, by the pores, to move into the coolant return flow space, and thus the coolant is able to move between the vapor diffusing space and the coolant return flow space. That is, this enables a heat pipe function that uses the vaporization and condensation of the coolant.

[0024] Additionally, because the pores have a structure wherein the shearing stresses in the vapor diffusing space do not propagate to the coolant return flow space, there is no interference between the diffusion of the vaporized coolant and the return flow of the condensed coolant. Because of this, it is possible to satisfy both (1) both of the coolants being able to move back and forth, with the coolant that condenses in the vapor diffusing path moving to the coolant return flow path and coolant in the coolant return path able to vaporize and move to the vapor diffusing path; and (2) the diffusion of the vaporized coolant and the return flow of the condensed coolant not interfering with each other. The result is that the heat transporting unit according to the Present Application is able to transport, in a specific direction and at high speed, heat that is removed from a heat-producing body.

[0025] The heat transporting unit according to a first invention according to the Present

Application comprises: an upper plate; a lower plate facing the upper plate; a coolant- fillable interior space formed between the upper plate and the lower plate; a vapor diffusing space for diffusing vaporized coolant, included in the interior space; a coolant return flow space for the return flow of the condensed coolant, included within the interior space; and an interference- preventing plate for preventing interference between the vaporized coolant that diffuses in the vapor diffusing space and the condensed coolant that flows back in the coolant return flow space; wherein: the interference-preventing plate has a plurality of pores for causing coolant that has condensed within the vapor diffusing space to move into the coolant return flow space, where the area of opening on the vapor diffusing space side of a pore is smaller than the area of opening on the coolant return flow space side.

[0026] This structure enables the heat transporting unit to be separated into a diffusing space for the vaporized coolant that diffuses in a specific direction and a return flow space for the condensed coolant that flows back in the direction opposite to the specific direction. Even when separated, in the heat transporting unit, the pores enable the coolant to move while preventing the propagation of the shearing stresses of the vaporized coolant. The satisfaction of both the separation and the movement makes it possible for the heat transporting unit to transport, rapidly and in a specific direction, the heat that is removed from the heat-producing body while preventing interference between the diffusion of the vaporized coolant and the return flow of the condensed coolant.

[0027] In a heat transporting unit according to a second invention according to the Present Application, in addition to the first invention, the vapor diffusing space and the coolant return flow space are divided by an interference-preventing plate.

[0028] This structure enables the heat transporting unit to be separated into a diffusing space for the vaporized coolant that diffuses in a specific direction and a return flow space for the condensed coolant that flows back in the direction opposite to the specific direction. Even when separated, in the heat transporting unit, the pores enable the coolant to move while preventing the propagation of the shearing stresses of the vaporized coolant.

[0029] In a heat transporting unit according to a third invention according to the Present

Application, in addition to the first and second inventions, the vaporized coolant diffuses along a first direction in the vapor diffusing space, and the condensed coolant flows back along a second direction, which is the opposite direction from the first direction, in the coolant return flow space.

[0030] This structure enables the heat transporting unit to transport, at a high speed, heat that is removed from the heat-producing body, doing so in a specific direction.

[0031] In a heat transporting unit according to a forth invention according to the Present

Application, in addition to the third invention, the heat transporting unit has a first end portion and a second end portion that is on the opposite side from the first end portion, where coolant that has been filled is vaporized by the heat of a heat-producing body that is disposed in the vicinity of the first end portion, the vapor diffusing space causes diffusion, along a first direction, of the vaporized coolant, a pore causes movement, into the coolant return flow space, of coolant that condenses in the process of diffusing from the first end portion to the second end portion, and the coolant return flow space causes condensed coolant, which has moved into the coolant return flow space, to flow along the second direction.

[0032] This structure enables the heat transporting unit to cause the condensed coolant to move to the coolant return flow space part way through the vapor diffusing space, while diffusing, along a specific direction, through the vaporized coolant, the heat that is removed from the heat- producing body. The result enables the heat transporting unit to transport heat, in a specific direction and at a high speed, by preventing the condensed coolant from interfering with the diffusion of the vaporized coolant in the vapor diffusing space.

[0033] In a heat transporting unit according to a fifth invention according to the Present Application, in addition to any of the first through fourth inventions, the pores not only move, to the coolant return flow space, coolant that has condensed in the vapor diffusing space, but also prevent the propagation, to the coolant return flow space, of shearing stresses of the vaporized coolant that diffuses within the vapor diffusing space.

[0034] This structure, through the pores, eliminates the propagation, to the coolant return flow space, of shearing stresses of the vaporized coolant that is diffusing. The result is the ability of the heat transporting unit to prevent the vapor diffusing space from interfering with the coolant return flow space.

[0035] In the heat transporting unit according to a sixth invention according to the Present

Application, in addition to any of the third through fifth inventions, an interference-preventing plate prevents vaporized coolant along a first direction from interfering with the return flow of condensed coolant along the second direction, through preventing the propagation of shearing stresses to the coolant return flow space.

[0036] This structure enables the heat transporting unit to transport, at a high speed, heat that is removed from the heat-producing body, through preventing interference between the vapor diffusing space and the coolant return flow space.

[0037] In a heat transporting unit according to a seventh invention according to the Present Application, in addition to any of the fourth through sixth inventions, the first end portion and/or the second end portion is further provided with an opening portion that connects between the vapor diffusing space and the coolant return flow space. [0038] In this structure, the heat transporting unit causes the condensed coolant to move more efficiently to the coolant return flow space at the end portion wherein there is more condensed coolant than vaporized coolant, and enables the heat transporting unit to move the vaporized coolant to the vapor diffusing space more efficiently at the end portion wherein there is more vaporized coolant than condensed coolant. The result is that the coolant transport cycle is faster, and the heat transporting unit is able to transport, at a high speed, the heat that is removed from the heat-producing body.

[0039] In a heat transporting unit according to an eight invention according to the Present Application, in addition to the seventh invention, an opening portion is provided in an interference-preventing plate, with area of opening that is larger than that of a pore.

[0040] This structure enables the heat transporting unit to move coolant efficiently between the vapor diffusing space and the coolant return flow space.

[0041] In a heat transporting unit according to a ninth invention according to the Present Application, in addition to any of the first through eighth inventions, the pores have a shape wherein the cross-sectional area thereof is larger nearer the coolant return flow space than the vapor diffusing space.

[0042] This structure enables the pores to not propagate to the coolant return flow space the shearing stresses by the vaporized coolant that diffuses in the vapor diffusing space.

[0043] In a heat transporting unit according to a 10th invention according to the Present Application, in addition to any of the first through ninth inventions, the upper plate and/or the lower plate has a plurality of grooves, where the plurality of grooves form a coolant return flow space.

[0044] This structure enables the heat transporting unit to form a coolant return flow space easily.

[0045] In a heat transporting unit according to an 11th invention according to the Present Application, in addition to the tenth invention, a plurality of grooves extend in the second direction.

[0046] This structure enables the coolant return flow space to cause the condensed coolant to flow back along the second direction.

[0047] In a heat transporting unit according to a 12 invention according to the Present

Application, in addition to the 10th or 11th invention, if grooves are provided in both the upper plate and the lower plate, a first interference-preventing plate is provided facing the upper plate, and a second interference-preventing plate is provided facing the lower plate.

[0048] This structure enables the heat transporting unit to cool the heat-producing body, without having to select the vertical orientation of the device. Additionally, the heat transporting unit is able to transport heat more quickly.

[0049] In a heat transporting unit according to the 13th invention according to the Present Application, in addition to any of the first through 12th inventions, the surface of the vapor diffusing space and/or the coolant return flow space has metal plating.

[0050] This structure enables the vapor diffusing space and the coolant return flow space to move the vaporized coolant and the condensed coolant efficiently.

[0051] In a heat transporting unit according to a 14th invention according to the Present Application, in addition to the 13th invention, the metal plating is of one or more metals selected from gold, silver, copper, aluminum, nickel, cobalt, or alloys thereof.

[0052] This structure enables the vapor diffusing space and the coolant return flow space to move the vaporized coolant and the condensed coolant efficiently.

[0053] In a heat transporting unit according to a 15th invention according to the Present Application, in addition to any of the fourth through 14th inventions, a heat radiating portion for cooling the vaporized coolant is also provided on a second end portion.

[0054] The heat that is transported is cooled rapidly by this structure, enabling the heat transporting unit to produce a rapid heat transporting cycle.

[0055] In a heat transporting unit according to a 16th invention according to the Present Application, in addition to any of the fourth through 15th inventions, a connecting portion for thermally connecting with the heat-producing body is further provided on the first end portion.

[0056] This structure enables the heat transporting unit to remove heat efficiently from the heat- producing body.

BRIEF DESCRIPTION OF THE FIGURES

[0057] The organization and manner of the structure and operation of the Present Application, together with further objects and advantages thereof, may best be understood by reference to the following Detailed Description, taken in connection with the accompanying Figures, wherein like reference numerals identify like elements, and in which: [0058] FIG. 1 is a perspective view of a heat transporting unit according to the first form of embodiment according to the Present Application;

[0059] FIG. 2 is an interior view of the heat transporting unit according to the first form of embodiment according to the Present Application;

[0060] FIG. 3 is a side sectional view of the heat transporting unit according to the first form of embodiment according to the Present Application;

[0061] FIG. 4 is a perspective view of an upper plate in the first form of embodiment according to the Present Application;

[0062] FIG. 5 is a perspective view of an upper plate in the first form of embodiment according to the Present Application;

[0063] FIG. 6 is a perspective view of a pore in the first form of embodiment according to the Present Application;

[0064] FIG. 7 is a side view of the pore in the first form of embodiment according to the Present Application;

[0065] FIG. 8 is an assembly perspective view of the heat transporting unit according to the first form of embodiment according to the Present Application;

[0066] FIG. 9 is an assembly perspective view of the heat transporting unit according to the first form of embodiment according to the Present Application;

[0067] FIG. 10 is a side sectional view of the heat transporting unit according to the first form of embodiment according to the Present Application;

[0068] FIG. 11 is an explanatory diagram illustrating the structures of pores in a Comparative Example 1, a Comparative Example 2, and an example of embodiment;

[0069] FIG. 12 is an explanatory diagram illustrating simulation results in the Comparative Example 1 in the first form of embodiment according to the Present Application;

[0070] FIG. 13 is an explanatory diagram illustrating simulation results in the Comparative Example 2 in the first form of embodiment according to the Present Application;

[0071] FIG. 14 is an explanatory diagram illustrating the simulation results in the example of embodiment in the first form of embodiment according to the Present Application;

[0072] FIG. 15 is a graph illustrating the results of the simulations in the first form of embodiment according to the Present Application; [0073] FIG. 16 is an assembly perspective view of a heat transporting unit according to a second form of embodiment according to the Present Application;

[0074] FIG. 17 is a side sectional view of the heat transporting unit according to the second form of embodiment according to the Present Application;

[0075] FIG. 18 is a schematic diagram of an electronic equipment according to a third form of embodiment according to the Present Application; and

[0076] FIG. 19 is a perspective view of the electronic equipment according to the third form of embodiment according to the Present Application. DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0077] While the Present Application may be susceptible to embodiment in different forms, there is shown in the Figures, and will be described herein in detail, specific embodiments, with the understanding that the disclosure is to be considered an exemplification of the principles of the Present Application, and is not intended to limit the Present Application to that as illustrated.

[0078] In the embodiments illustrated in the Figures, representations of directions such as up, down, left, right, front and rear, used for explaining the structure and movement of the various elements of the Present Application, are not absolute, but relative. These representations are appropriate when the elements are in the position shown in the Figures. If the description of the position of the elements changes, however, these representations are to be changed accordingly.

[0079] Forms of embodiment according to the Present Application will be explained below in reference to the drawings.

[0080] Note that the "heat pipe" in the present Specification refers to a member, component, or device that achieves a function of cooling a heat-producing body through a coolant that is filled into an interior space thereof, through repetitive vaporization, through heat being received from the heat-producing body and the vaporized coolant being cooled to condense. Furthermore, in the present Specification, the heat transporting unit refers to a member, component, or device having the function of transporting heat from the heat-producing member through the movement of a coolant.

[0081] The heat transporting unit according to the Present Application makes use of the function and operation of a heat pipe, and thus the concept of a "heat pipe" will be explained first. [0082] A heat pipe is filled with a coolant, and a surface thereof, which is a heat-receiving surface, contacts a heat-producing body that is, for example, an electronic component. This internal coolant receives heat from the heat-producing body to be vaporized, and, at the time of vaporization, removes heat from the heat-producing body. The vaporized coolant moves within the heat pipe. The heat of the heat-producing body is carried by this movement. The vaporized coolant that has moved condenses through being cooled at a heat radiating surface, or the like (or by a secondary cooling member such as a heat sink or a cooling fan, or the like). The coolant that has condensed to form a liquid flows back within the heat pipe to move again to the heat- receiving surface. The coolant that has moved to the heat-receiving surface again vaporizes to remove heat from the heat-producing body.

[0083] The heat pipe cools the heat-producing body through repetitive vaporization and condensation of the coolant in this way. Because of this, preferably the heat pipe has, internal thereto, a vapor diffusing space for diffusing the vaporized coolant, and a coolant return flow space for causing the condensed coolant to flow back. Such a heat pipe, having the vapor diffusing space and the coolant return flow space, can transport, in a particular direction, the heat that is removed from the heat-producing body.

[0084] An overall summary of a heat transporting unit according to a first form of embodiment will be explained using FIG. 1 through FIG. 3.

[0085] FIG. 1 is a perspective view of a heat transporting unit according to the first form of embodiment according to the Present Application. FIG. 2 is an interior view of the heat transporting unit according to the first form of embodiment according to the Present Application. FIG. 3 is a side view diagram of the heat transporting unit according to the first form of embodiment according to the Present Application.

[0086] FIG. 1 illustrates a state wherein the end portion of the heat transporting unit 1 is cut away to expose the inside. FIG. 2 illustrates a state when the interference-preventing plate provided within the heat transporting unit 1 is viewed from above. FIG. 3 illustrates a state wherein the interior of the heat transporting unit 1 is visible, where the paths of movement of the vaporized coolant and the condensed coolant are indicated by dotted arrows.

[0087] The heat transporting unit 1 has an upper plate 2, a lower plate 3 that faces the upper plate 2, and an interior space 4 that is formed by the upper plate 2 and the lower plate 3. A coolant can be filled into the interior space 4. Additionally, the heat transporting unit 1 is provided with a vapor diffusing space 5 and a coolant return flow space 6 that are included within the interior space 4. The vapor diffusing space 5 diffuses the vaporized coolant. The coolant return flow space 6 causes the condensed coolant to flow back. Additionally, the heat transporting unit 1 is provided with an interference-preventing plate 7 for preventing interference between the vaporized coolant that diffuses within the vapor diffusing space 5 (hereinafter termed the "vaporized coolant") and the condensed coolant that flows back in the coolant return flow space (hereinafter termed the "condensed coolant").

[0088] The interference-preventing plate 7 has a plurality of pores that cause the coolant that condenses within the vapor diffusing space 5 to move into the coolant return flow space 6, where the area of opening on the vapor diffusing space 5 side of the pores 8 is smaller then the area of opening on the coolant return flow space 6 side.

[0089] The heat transporting unit 1 first forms an interior space 4 by the upper plate 2 and the lower plate 3. At this time, the end portions of the upper plate 2 and the lower plate 3 have a structure that seals the interior space 4. When the upper plate 2 and the lower plate 3 are put together, an interior space 4 with a closed periphery is formed. The interference-preventing plate 7 is layered between the upper plate 2 and the lower plate 3, where the interference-preventing plate 7 is provided within the interior space 4.

[0090] The coolant is filled within the interior space 4, and the vaporized coolant diffuses, and the condensed coolant flows back, within this interior space 4, and the interior space 4 is divided into an upper plate 2 side and a lower plate 3 side by the interference-preventing plate 7. The space on the upper plate 2 side forms a vapor diffusing space 5 for diffusing the vaporized coolant, and the space on the lower plate 3 side forms a coolant return flow space 6 that causes the condensed coolant to flow back. Note that the "upper plate 2" and "lower plate 3" are terms for convenience in differentiation, but they need not necessarily match up and down physically. Of course, the vapor diffusing space 5 need not necessarily be physically at the top within the interior space 4, nor must the coolant return flow space 6 necessarily be physically at the bottom within the interior space 4.

[0091] In this way, the interference-preventing plate 7 separates the interior space 4 into a vapor diffusing space 5 and a coolant return flow space 6. The result is that the coolant that is filled into the interior space 4, when it vaporizes to become vaporized coolant, diffuses in a specific direction (the first direction in FIG. 1) within the vapor diffusing space 5, and when it condenses to become condensed coolant, it flows back in a specific direction (the opposite direction from the first direction in FIG. 1) in the coolant return flow space 3.

[0092] In the heat transporting unit 1, the vaporized coolant diffuses in the first direction using the vapor diffusing space 5, and the condensed coolant flows back in the direction opposite to the first direction using the coolant return flow space 6. The result is that the heat transporting unit 1 is able to transport, rapidly and along the first direction, heat that is removed from the heat- producing body.

[0093] If the interior space 4 were not divided into the vapor diffusing space 5 and the coolant return flow space 6, the diffusion of the coolant that is vaporized by the heat from the heat- producing body and the return flow of the coolant condensed by cooling would interfere with each other. This interference would slow both the speed of diffusion of the vaporized coolant and the speed of return flow of the condensed current. If the diffusion speed and the return flow speed were slowed, then the speed of transport of the heat removed from the heat-producing body would be slowed.

[0094] On the other hand, the heat transporting unit 1 that is divided into the vapor diffusing space 5 and the coolant return flow space 6 by the interference-preventing plate 7, shown in the first form of embodiment, does not have interference between the diffusion of the vaporized coolant and the return flow of the condensed coolant, and thus the speed of diffusion and the speed of return flow are increased. As a result, the heat transporting unit 1 can transport, at a high speed, the heat that is removed from the heat-producing body.

[0095] Additionally, the interference-preventing plate 7 has a plurality of pores 8. The pores 8 cause the condensed coolant to move from the vapor diffusing space 5 to the coolant return flow space 6 when the vaporized coolant that is diffusing within the vapor diffusing space 5 condenses. This movement causes the condensed coolant to arrive in the coolant return flow space 6, so that the condensed coolant flows back through the coolant return flow space 6. The vaporized coolant that diffuses through the vapor diffusing space 5 may condense at the end portion of the vapor diffusing space 5, due to the external environment of the heat transporting unit 1, or may instead condense part way through. The interference preventing plate 7 is provided with a plurality of pores 8, so that regardless of whether the coolant has condensed part way through the vapor diffusing space 5 or the coolant has condensed at the end portion thereof, the condensed coolant can be moved by the pores 8 from the vapor diffusing space 5 to the coolant return flow space 6.

[0096] Here the area of opening of the pores 8 on the vapor diffusing space 5 side is smaller than the area of opening on the coolant return flow space 6 side. The imbalance in the areas of opening of the pores 8 prevents the propagation, to the coolant return flow space 6, of the shearing stresses of the vaporized coolant that is diffusing within the vapor diffusing space 5.

[0097] The result is that the pores 8 not only move the condensed coolant in various places within the vapor diffusing space 5, but also can prevent the propagation of the shearing stresses of the vaporized coolant.

[0098] The interference-preventing plate 7, as illustrated in FIG. 2, is provided with pores 8 across the entirety thereof. Of course, the provision across the entirety thereof is not an absolute requirement, but rather the pores 8 may instead be provided in only a portion of the interference- preventing plate 7. The pores 8 have the role of moving the condensed coolant, and thus the diameter may be of a size so as to apply a capillary force.

[0099] The operating mechanism of the heat transporting unit 1 will be explained using FIG. 3.

[0100] FIG. 3 illustrates a state wherein the inside of the heat transporting unit 1 is visible from the side. The interior space 4 is divided by the interference-preventing plate 7 into the vapor diffusing space 5 and the coolant return flow space 6.

[0101] The heat transporting unit 1 has a flat rectangular plate shape, and has a shape that is long in a first direction. A heat-producing body 20 is disposed at the bottom face of the lower plate 3 that is the first end portion 13 that is one end of the end portion of the heat transporting unit 1.

The heat-producing body 20 includes elements that produce a large amount of heat, such as electronic components, light-emitting elements, power devices, and the like.

[0102] In the heat transporting unit 1, a coolant is filled in advance into the interior space 4, and coolant that is in the liquid form accumulates in the coolant return flow space 6. The lower plate

3 removes heat from the heat-producing body 20. The coolant is vaporized by this heat, and the vaporized coolant passes through the pores 8 to move from the coolant return flow space 6 to the vapor diffusing space 5. This movement is indicated by the dotted arrows 18.

[0103] Following this, the vaporized coolant diffuses along the first direction in the vapor diffusing space 5. The heat-producing body 20 that is the heat source is at the end portion of the heat transporting unit 1, so the vaporized coolant has a force that moves it from the high temperature position to the low temperature position, and that the vaporized coolant diffuses along the first direction. The dotted arrows 15 indicate the state of the diffusion of the vaporized coolant along the first direction in the vapor diffusing space 5.

[0104] The vaporized coolant, while diffusing in the vapor diffusing space 5, is cooled by the effect of the external environment. Some or all of the vaporized coolant is condensed by this cooling. The vaporized coolant may condense part way through the vapor diffusing space 5, or may condense after arriving at the second end portion 14. Typically, the coolant that condenses part way through the vapor diffusing space 5 and the coolant that condenses after arriving at the second end portion 14 can be considered to be mixed together.

[0105] The pores 8 are provided in the interference-preventing plate corresponding to the entirety of the vapor diffusing space 5. Because of this, the coolant that has condensed part way through the vapor diffusing space 5 moves into the coolant return flow space 6 through the pores 8 that are provided part way through the vapor diffusing space 5. Moreover, the coolant that condenses at the second end portion 14 of the vapor diffusing space 5 move through the pores 8 provided in the vicinity of the second end portion 14 to the coolant return flow space 6. The dotted arrows 17 indicate the state of the movement of the condensed coolant through the pores 8 to the coolant return flow space 6.

[0106] The pores 8 are provided at a variety of positions within the vapor diffusing space 5, and thus the condensed coolant can move into the coolant return flow space 6 nearest the condensed coolant. There is essentially no accumulation of condensed coolant in the vapor diffusing space 5, and thus there is no impediment when the vaporized coolant diffuses within the vapor diffusing space 5. Because there is no impediment, the vapor diffusing space 5 can diffuse the vaporized coolant at a high speed in the first direction.

[0107] The condensed coolant that has moved flows back along the second direction, which is opposite of the first direction, in the coolant return flow space 6. This is because the gas pressure is reduced 1 , through the absorption of heat, at the first end portion 142 wherein the heat- producing body 20 is disposed, and the condensed coolant moves to the first end portion 13 wherein the gas pressure is reduced. The dotted arrow 16 indicates the return flow of the condensed coolant along the second direction. [0108] The condensed coolant that has flowed back along the second direction in the coolant return flow space 6 flows back to the first end portion 13. The condensed coolant that has flowed back to the first end portion 13 is vaporized again by the heat of the heat-producing body 20, and passes through the pores 8 to move into the vapor diffusing space 5. The vaporized coolant that has moved into the vapor diffusing space 5 diffuses again along the first direction.

[0109] Additionally, when the diffusion of the vaporized coolant and the return flow of the condensed coolant are iterated, it is difficult for the shearing forces of the vaporized coolant that diffuses within the vapor diffusing space 5 to propagate through the pores 8 to the coolant return flow space 6. This is because the area of opening of the pores 8 on the vapor diffusing space 5 side is smaller than the area of opening of the pores 8 on the coolant return flow 6 side. The result is that there is no interference when the condensed coolant flows back through the coolant return flow space 6, and thus the coolant return flow space 6 can cause the condensed coolant to flow back along the second direction quickly.

[0110] By preventing the shearing stresses of the vaporized coolant that propagates through the vapor diffusing space 5 from propagating to the coolant return flow space 6, the interference- preventing plate 7 prevents the diffusion of vaporized coolant in the first direction from interfering with the return flow of the condensed coolant along the second direction.

[0111] In this way, through iterating the diffusion of the vaporized coolant along the first direction and the return flow of the condensed coolant along the second direction, the heat transporting unit 1 is able to transport, rapidly and along the first direction, the heat that is removed from the heat-producing body 20. In particular, when the vapor diffusing space 5 and the coolant return flow space 6 are divided by the interference-preventing plate 7, the diffusion of the vaporized coolant and the return flow of the condensed coolant do not interfere with each other through the pores 8. This non-interference increases the diffusion speed of the vaporized coolant and the return flow speed of the condensed coolant.

[0112] Given the above, the heat transporting unit 1 according to the first form of embodiment is able to transport the heat at a high speed in a particular direction. The heat from the heat- producing body that is disposed at one location can be moved at a high speed to another location through the high-speed transport of the heat, thus enabling the cooling of a heat-producing body that is mounted in, for example, electronic equipment, transportation equipment, industrial equipment, or the like, that has a complex shape, to be performed flexibly. [0113] The details of each portion will be explained next.

[0114] The upper plate 2 will be explained next.

[0115] The upper plate 2 has a flat shape, and, preferably, is a rectangle that has a short direction and a long direction. Of course, it may have a shape that, in portions, is different from a rectangular shape, and may have a curved or bent shape. However, because the upper plate 2 has a short direction and a long direction, the heat transporting unit 1 has a short direction and a long direction, and thus the heat transporting unit 1 is able to transport, in a particular direction, heat from the heat-producing body that is disposed at the end portion thereof.

[0116] The upper plate portion 2 is formed from metal, plastic, or the like, and, preferably, is formed from a metal having high thermal conductivity and high corrosion resistance (or high durability), such as copper, aluminum, silver, aluminum alloy, iron, iron alloy, stainless steel, or the like.

[0117] The upper plate 2 forms an interior space 4 together with the lower plate 3. For example, the upper plate 2 and the lower plate 3 have raised portions or wall members around the peripheral edges thereof in order to form the interior space 4. The upper plate 2 and the lower plate 3, through connecting through these raised portions or wall members, form the interior space 4 between the upper plate 2 and the lower plate 3. The raised portions or wall members, when contacting the lower plate 3, form side walls surrounding the interior space 4. Of course, these raised portions or wall members may be either separate members from the upper plate 2 or the same member.

[0118] Additionally, the upper plate portion 2 may have a plurality of grooves along the lengthwise direction thereof, as illustrated in FIG. 4. FIG. 4 is a perspective view of the upper plate in the first form of embodiment according to the Present Application. Grooves 30 form the coolant return flow space 6. While the vapor diffusing space 5 and the coolant return flow space 6 may be formed on either the upper plate 2 side or the lower plate 3 side, this depends on the application and the conditions of use, so grooves 30 for forming the coolant return flow space 6 may be formed on the upper plate 2 as well.

[0119] Additionally, preferably the upper plate 2 has metal plating on at least the surface that contacts the interior space 4 (the surface by which the vaporized coolant passes). The provision of the metal plating promotes the diffusion of the vaporized coolant. Gold, silver, copper, aluminum, nickel, cobalt, and/or an alloy thereof may be selected as the metal for the metal plating thereof. Of course, the plating may be a single-layer plating, a multilayer plating, electrolytic plating, or non-electrolytic plating.

[0120] While the upper plate 2 is nominally "upper," physically it need not necessarily be disposed upwardly, but rather is a term for convenience. The heat-producing portion may be connected to the upper plate 2, or may be connected to the lower plate 3.

[0121] Additionally, the upper plate 2 is provided with a filling hole for filling the coolant.

When the interior space 4 is formed through the upper plate 2 and the lower plate 3 being put together, it is then necessary to fill the coolant into the interior space 4. The filling opening is plugged after the coolant is filled.

[0122] Note that the coolant may be filled through the filling opening after the upper plate 2 and the lower plate 3 are brought together, or may be filled when they are brought together.

Additionally, the filling of the coolant preferably is performed under a vacuum or under a reduced pressure. Filling under a vacuum or under reduced pressure causes the coolant to be filled in a state wherein the interior space 4 is under a vacuum or under a reduced pressure.

When under a reduced pressure, the vaporization and condensation temperature of the coolant will be reduced, and thus there will be the benefit of activating the iterative vaporization and condensation of the coolant.

[0123] Furthermore, as illustrated in FIG. 5, the upper plate 2 may be provided with grooves 31 having the shape of a grid. The grid-shaped grooves 31 form the coolant return flow space 6 in the same manner as in the case of FIG. 4. FIG. 5 is a perspective view of the upper plate in the first form of embodiment according to the Present Application.

[0124] The grooves having a grid shape produce capillary forces, making it easier for the coolant return flow space 6 to cause the condensed coolant to flow back.

[0125] The lower plate 3 will be explained next. The lower plate 3 has the same shape and structure as the upper plate 2. Because of this, the lower plate 3 is illustrated by substituting into FIG. 4 and FIG. 5 that are plan views of the upper plate 2.

[0126] The lower plate 3 has a flat shape, and, preferably, has a short direction and a long direction. In particular, the lower plate 3 is brought into contact facing the upper plate 2, and thus preferably has essentially the same shape and the same area as the upper plate 2. However, the lower plate 3 may have a different area and shape from the upper plate 2, insofar as it can form the interior space 4 together with the upper plate 2. Of course, it may have a shape that is different from rectangular in parts, and may have a curved or bent shape. Note that, as with the upper plate 2, the lower plate 3 is a rectangular shape having a short direction and a long direction, and thus the heat transporting unit 1 is a rectangular shape having a short direction and a long direction, so the heat transporting unit 1 is able to transport heat, in a particular direction, from the heat-producing body that is disposed on the end portion thereof.

[0127] The lower plate 3 is formed from metal, plastic, or the like, and, preferably, is formed from a metal having high thermal conductivity and high corrosion resistance (or high durability), such as copper, aluminum, silver, aluminum alloy, iron, iron alloy, stainless steel, or the like.

[0128] The lower plate 3 is put together with the upper plate 2, to form the interior space, and thus there may be raised portions or wall members around the periphery edge thereof to form the interior space 4. When brought together with the upper plate 2, these raised portions or wall members form sidewalls encompassing the interior space 4. Of course, the raised portions or wall members may be separate members from the lower plate 3, or may be the same member. Note that both the upper plate portion 2 and the lower plate 3 may have raised portions or wall members, or either the upper plate 2 or the lower plate 3, one or the other, may have raised portions or wall members.

[0129] Furthermore, the lower plate 3, as with the upper plate 2, may be provided with grooves 30 or 31, as in FIG. 4 and FIG. 5. These grooves 30 and 31 form the coolant return flow space 6. When the lower plate 3 is provided with the grooves 30 along the second direction (first direction), the condensed coolant flows back along the second direction, and when provided with grid-shaped grooves 31, the return flow of the condensed coolant is made easier through capillary forces.

[0130] Additionally, as with the upper plate 2, the lower plate 3 may be provided with a filling hole for the coolant.

[0131] The lower plate 3 is brought together facing the upper plate 2 in order to form the interior space 4.

[0132] Additionally, preferably the lower plate 3 has metal plating on at least the surface that contacts the interior space 4 (the surface by which the vaporized coolant passes). The provision of the metal plating promotes the diffusion of the vaporized coolant. Gold, silver, copper, aluminum, nickel, cobalt, and/or an alloy thereof may be selected as the metal for the metal plating thereof. Of course, the plating may be a single-layer plating, a multilayer plating, electrolytic plating, or non-electrolytic plating.

[0133] While the lower plate 3 is nominally "Lord," physically it need not necessarily be disposed downwardly, but rather is a term for convenience. The heat-producing portion may be connected to the lower plate 3, or may be connected to the upper plate 2.

[0134] The interference-preventing plate 7 will be explained next. Not only does the

interference-preventing plate 7 divide the interior space 4 into the vapor diffusing space 5 and the coolant return flow space 6, but also prevents interference between the vaporized coolant that diffuses in the vapor diffusing space 5 and the condensed coolant that flows back in the coolant return flow space 6.

[0135] The interference-preventing plate 7 faces the upper plate 2 and the lower plate 3, and is layered therebetween. Either a single interference-preventing plate 7 or a plurality of

interference-preventing plates 7 may be provided.

[0136] The interference-preventing plate 7 has a plurality of pores 8, where the pores 8 cause the coolant that condenses in the vapor diffusing space 5 to move into the coolant return flow space 6. The area of opening of the pores 8 on the vapor diffusing space 5 side is smaller than the area of opening of the pores 8 on the coolant return flow space 6 side. The area of opening of the pores 8 being larger on the coolant return flow space 6 side in this way prevents the propagation, to the coolant return flow space 6, of the shearing stresses of the vaporized coolant diffusing in the vapor diffusing space 5. This prevention prevents the vaporized coolant that diffuses in the first direction in the vapor diffusing space 5 from interfering with the condensed coolant that flows in the coolant return flow space 6.

[0137] As illustrated in FIG. 3, a single interference-preventing plate 7 may be layered between the upper plate 2 and the lower plate 3, and the upper plate 2 side may be the vapor diffusing space 5 and the lower plate 3 side may be the coolant return flow space 6. In this way, the interior space 4 is divided into a top and bottom by the interference-preventing plate 7, with the top side as the vapor diffusing space 5 and the bottom side as the coolant return flow space 6.

[0138] Because the interference-preventing plate 7 is layered between the upper plate 2 and the lower plate 3, it is appropriate to have the same shape, material, and size as the upper plate 2 and the lower plate 3. That is, when the upper plate 2 and the lower plate 3 are rectangles having a short direction and a long direction, then the interference-preventing plate 7 will also have the same structure.

[0139] The interference-preventing plate 7 may be made from metal or plastic, but preferably is made from a metal with high thermal conductivity, or a high corrosion resistance (or durability), such as copper, aluminum, silver, aluminum alloy, iron, iron alloy, stainless steel, or the like.

Additionally, the interference-preventing plate 7, together with the upper plate 2, forms the vapor diffusing space 5, and, preferably wall members or raised portions are provided on the peripheral edges of the interference-preventing plate 7 so that there will be a specific facing distance between the upper plate 2 and the interference-preventing plate 7.

[0140] Additionally, preferably the interference-preventing plate 7 has metal plating on at least the surface that contacts the interior space 4 (the surface by which the vaporized coolant passes). The provision of the metal plating promotes the diffusion of the vaporized coolant. Gold, silver, copper, aluminum, nickel, cobalt, and/or an alloy thereof may be selected as the metal for the metal plating thereof. Of course, the plating may be a single-layer plating, a multilayer plating, electrolytic plating, or non-electrolytic plating.

[0141] The interference-preventing plate 7 is layered together with the upper plate 2 and the lower plate 3.

[0142] Additionally, when both the upper plate 2 and the lower plate 3 are each provided with grooves 30 and 31 so that either may form the coolant return flow space 6, a first interference- preventing plate 7 is layered facing the upper plate 2 and a second interference-preventing plate

7 is formed facing the bottom plate 3. Layering in this way forms a vapor diffusing space 5 in the heat transporting unit 1 in the center portion in the direction of thickness thereof, and coolant return flow spaces 6 are formed on both the top and bottom thereof.

[0143] The pores 8 are a plurality of through-holes provided in the interference-preventing plate 7, to physically connect between the vapor diffusing space 5 and the coolant return flow space 6.

[0144] The pores 8 may be formed across the entirety of the lengthwise direction of the interference-preventing plate 7, or may be formed in only a portion thereof. Moreover, the pores

8 may be formed across the entirety of the short direction of the interference-preventing plate 7, or may be formed in only a portion thereof.

[0145] When the pores 8 are formed in only a portion of the interference-preventing plate 7 in the lengthwise direction, preferably the pores 8 are formed only in both end portions and in the vicinity of the center in the lengthwise direction. This is because the vaporized coolant tends to condense primarily at the end portions and in the vicinity of the center.

[0146] Additionally, when the pores 8 are formed in only a portion of the short direction of the interference preventing plate 7, preferably the pores 8 are provided primarily at the peripheral edge. This is because the vaporized coolant condenses primarily at the peripheral edge.

[0147] The plurality of pores 8 may be formed with equal spacing, or may be provided at non- equal spacing. The plurality of pores 8 may have sizes and cross-sectional areas that are either mutually different or identical, and the shapes thereof may either be different or identical.

[0148] The provision of the pores 8 in the interference-preventing plate 7 that separates the vapor diffusing space 5 and the coolant return flow space 6 causes the coolant that has condensed in the vapor diffusing space 5 to move to the coolant return flow space 6. Of course, conversely, it also the coolant that has vaporized in the coolant return flow space 6 to move to the vapor diffusing space 5. In this way, the pores 8 achieve, as a first function, the movement of coolant between the vapor diffusing space 5 and the coolant return flow space 6 that are divided by the diffusion preventing plate 7.

[0149] Additionally, the area of opening of the pores 8 on the vapor diffusing space 5 side is smaller than the area of opening thereof on the coolant return flow space 6 side. The area of opening on the vapor diffusing space 5 side being smaller than the area of opening on the coolant return flow space 6 side can prevent the propagation, to the coolant return flow space 6, of the shearing stresses of the vaporized coolant that is diffusing in the vapor diffusing space 5. This is because the area of opening on the vapor diffusing space 5 side being smaller than the area of opening on the coolant return flow space 6 side makes it difficult for the vaporized coolant to enter into the pores 8, unlike the condensed coolant that is moved by capillary forces.

[0150] FIG. 6 is a perspective view of a pore in the first form of embodiment according to the Present Application. FIG. 7 is a side view diagram of a pore in the first form of embodiment according to the Present Application. Both illustrate that the area of opening of the pores 8 on the vapor diffusing space 5 side is smaller than the area of opening thereof on the coolant return flow space 6 side. Note that FIG. 6 illustrates the state where the pore 8 is viewed from the coolant return flow space 6 side, in order to illustrate the shape of the pore 8 for ease in understanding.

[0151] The pores 8 illustrated in FIG. 6 and FIG. 7 have a spindle shape (a tapered shape), having a shape wherein the cross-sectional size thereof increases gradually towards the coolant return flow space 6 from the vapor diffusing space 5. Having the spindle shape in this way prevents the propagation, to the coolant return flow space 6, of the shearing forces of the vaporized coolant that is diffusing in the vapor diffusing space 5.

[0152] The gradual enlargement of the cross-sectional area can be seen clearly in FIG. 7.

[0153] Of course, because the shape of the pores 8 is established so as to prevent the

propagation, to the coolant space 6, of the shearing stresses of the vaporized coolant that is diffusing in the vapor diffusing space 5, the shapes of the pores include a variety of shapes that achieve this imbalance in the areas of opening. For example, a spiral groove may be provided on the inside of the pore 8. Conversely, a step- shape may be provided. However, because a plurality of pores 8 is formed in the interference-preventing plate 7, spindle-shaped pores 8 are formed, as illustrated in FIG. 7, for ease in the manufacturing process.

[0154] The pores 8, as described above, not only achieve the movement of the coolant in³ the vapor diffusing space 5 and the coolant return flow space 6, which are divided by the

interference-preventing plate 7, but, as a second function, prevent the propagation, to the coolant return flow space 6, of the shearing stresses of the vaporized coolant that is diffusing in the vapor diffusing space 5.

[0155] In the vapor diffusing space 5, the vaporized coolant diffuses in the first direction, and in the coolant return flow space 6, the condensed coolant flows back in the second direction (the opposite direction from the first direction). Preventing the propagation of the shearing stresses to the coolant return flow space 6 makes it possible to prevent the diffusion of the vaporized coolant along the first direction in the vapor diffusing space 5 from interfering with the return flow of the condensed coolant along the second direction in the coolant return flow space 6.

[0156] The result is that the speed of diffusion of the vaporized coolant along the first direction in the vapor diffusing space 5 and the speed of return flow of the condensed coolant along the second direction in the coolant return flow space 6 will be faster, increasing the heat transport cycling in the specific direction in the heat transporting unit 1.

[0157] The vapor diffusing space 5 and the coolant return flow space 6 are formed by the contact between the upper plate 2 and the lower plate 3, and the interference-preventing plate 7 layered therebetween. When a single interference-preventing plate 7 is layered between the upper plate 2 and the lower plate 3, a vapor diffusing space 5 is formed on the upper plate 2 side, and a coolant

³ sic return flow space 6 is formed on the lower plate 3 side. This is as illustrated in FIG. 3. Of course, the upper plate 2 and the lower plate 3 are nominal, for convenience, and do not mean that the vapor diffusing space 5 is necessarily formed on the top side of the heat transporting unit 1, nor that the coolant return flow space 6 is formed at the bottom.

[0158] As illustrated in FIG. 3, when the heat transporting unit 1 is provided with a single vapor diffusing space 5 and a single coolant return flow space 6, then when the vaporized coolant diffusing through the vapor diffusing space 5 condenses, it moves to the coolant return flow space 6 through pores 8, and the condensed coolant that has thus moved flows back through the coolant return flow space 6.

[0159] Additionally, when a single interference-preventing plate 7 is layered between the upper plate 2 and the lower plate 3, the vapor diffusing space 5 is formed in this space wherein the upper plate 2 and the interference-preventing plate 7 face each other. Because of this, preferably wall members are provided around the peripheral edge on the sides that are facing each other of the upper plate 2 and/or the interference-preventing plate 7. Because the upper plate 2 and the interference-preventing plate 7 are layered together having a specific facing distance

therebetween, due to the wall members, this facing distance forms the vapor diffusing space 5.

[0160] In contrast, when the coolant return flow space is formed through grooves 30, the layering may be without the facing distance between the lower plate 3 and the interference- preventing plate 7.

[0161] When the heat transporting unit 1 has a single vapor diffusing space 5 and a single coolant return flow space 6, preferably the coolant return flow space 6 side is disposed on the bottom, in order to facilitate the movement of the condensed coolant from the vapor diffusing space 5 to the coolant return flow space 6.

[0162] On the other hand, as illustrated in FIG. 8, both the upper plate 2 and the lower plate 3 may have grooves 30, and not only may the grooves 30 that are provided in the upper plate 2 form the vapor diffusing space 5, but the grooves 30 that are provided in the lower plate 3 may form the coolant return flow space 6. In this case, a first interference-preventing plate 7 may be layered facing the upper plate 2 and a second interference-preventing plate 7 may be layered facing the lower plate 3. This will form coolant return flow spaces 6 at both the top and the bottom of the heat transporting unit 1, and a vapor diffusing space 5 will be formed interposed between the coolant return flow spaces 6 that are formed at the top and bottom surfaces thereof. [0163] That is, vaporized coolant will diffuse through the vapor diffusing space 5 that is interposed between the coolant return flow space 6 on the top side and the coolant return flow space 6 on the bottom side in the heat transporting unit 1. When vaporized coolant condenses part way through the vapor diffusing space 5, or at the end portion thereof, it moves through the pores 8 to the coolant return flow space 6 at the top or moves to the coolant return flow space 6 at the bottom. The coolant return flow space 6 on the top and the coolant return flow space 6 at the bottom cause the condensed coolant to flow back.

[0164] FIG. 8 is an assembly perspective diagram of the heat transporting unit according to the first form of embodiment according to the Present Application. The heat transporting unit 1 is formed by layering the upper plate 2, the lower plate 3, and two interference-preventing plates 7. Note that in FIG. 8, to enable the viewing of the grooves 30 of the upper plate 2, the upper plate 2 is shown in a state wherein the top face is not covered. Moreover, in FIG. 8 the heat transporting unit 1 has a structure wherein two interference-preventing plates 7 are layered between the upper plate 2 and the lower plate 3, and an intermediate plate 40 for forming the vapor diffusing space 5 is layered as well. The intermediate plate 40 secures the facing distance between the two interference-preventing plates 7, where this facing distance forms the vapor diffusing space 5. That is, the two interference-preventing plates 7 separate the vapor diffusing space 5 and the coolant return flow spaces 6.

[0165] In sequence from the top in FIG. 8 are layered the upper plate 2, an interference- preventing plate 7, the intermediate plate 40, an interference-preventing plate 7, and the lower plate 3.

[0166] Additionally, as illustrated in FIG. 9, the heat transporting unit 1 may be formed through an upper plate 2 and a lower plate 3 having grid- shaped grooves 31. FIG. 9 is an assembly perspective view of a heat transporting unit according to the first form of embodiment according to the Present Application. FIG. 9 illustrates each of the members that structure the heat transporting unit 1, in the same manner as in FIG. 8.

[0167] The coolant return flow space 6 is formed from the grid-shaped grooves 31. Because the coolant return flow space 6 has the grid-shaped grooves 31, a strong capillary force is provided, making it possible to cause the condensed coolant to flow back efficiently. In sequence from the top in FIG. 9 are provided the upper plate 2, an interference-preventing plate 7, the intermediate plate 40, an interference-preventing plate 7, and the lower plate 3, to structure the heat transporting unit illustrated in FIG. 10.

[0168] FIG. 10 is a side sectional diagram of a heat transporting unit according to the first form of embodiment according to the Present Application. Because FIG. 10 is structured through stacking the members illustrated in FIG. 9, coolant return flow spaces 6 are provided in both the upper plate 2 side and the lower plate 3 side (that is, grooves 31 form the coolant return flow spaces 6), and a vapor diffusing space 5 is formed between the coolant return flow spaces 6 (interposed between two interference-preventing plates 7). That is, a vapor diffusing space 5 is formed in the vicinity of the center of the heat transporting unit 1 in the direction of thickness thereof, where the coolant moves between the vapor diffusing space 5 and the coolant return flow spaces 6 at the top and the bottom.

[0169] As illustrated by the dotted arrows in FIG. 10, the vaporized coolant diffuses along the first direction within the vapor diffusing space 5. The coolant that condenses part way through the vapor diffusing space 5, or at the end portion thereof, moves through the pores 8 into the coolant return flow space 6 on the upper plate 2 side, or moves through the pores 8 into the coolant return flow space 6 on the lower plate 3 side. Depending on the state of use, the condensed coolant may either move into the coolant return flow space 6 on the upper plate 2 side, or may move into the coolant return flow space 6 on the lower plate 3 side.

[0170] Additionally, as illustrated in FIG. 10, not only is a vapor diffusing space 5 formed in the center portion in the direction of thickness by the two interference-preventing plates 7, but also coolant return flow spaces 6 are formed at the top and bottom in the direction of thickness (that is, at the upper plate 2 side and the lower plate 3 side), to form a heat transporting unit 1 that is vertically symmetrical. The structure of the heat transporting unit 1 being vertically symmetrical means that there is need to select top or bottom when installing the heat transporting unit 1.

[0171] When the heat transporting unit 1 is viewed from the outside, it is difficult to discern between the top and the bottom. There may be cases wherein it would be difficult for the coolant that condenses in the vapor diffusing space 5 that is positioned at the bottom to move to the coolant return flow space 6 that is positioned at the top, if, for example, the heat transporting unit 1 were installed with the coolant return flow space 6 at positioned at the top and the vapor diffusing space 5 positioned at the bottom. [0172] With the vertically symmetrical heat transporting unit 1 illustrated in FIG. 10, regardless of which side is placed upward, still there is a coolant return flow space 6 below the vapor diffusing space 5. In this case, the coolant that condenses in the vapor diffusing space 5 can move easily through the pores 8 to the coolant return flow space 6.

[0173] As described above, the heat transporting unit 1 illustrated in FIG. 10 can be used without selecting the installation orientation.

[0174] Of course, the pores 8 move the condensed coolant through capillary forces, and thus can move the condensed coolant from a vapor diffusing space 5 positioned at the bottom to a coolant return flow space 6 positioned at the top.

[0175] The manufacturing process will be explained next. As illustrated in FIG. 8 and FIG. 9, the heat transporting unit 1 is manufactured through layering the respective members that are the upper plate 2, the lower plate 3, the intermediate plate 40, and the interference-preventing plate 7.

[0176] The upper plate 2, the lower plate 3, the intermediate plate 40, and the interference- preventing plate 7 are each aligned with specific positional relationships. The upper plate 2, the lower plate 3, the intermediate plate 40, and/or the interference-preventing plate 7 have bonding protrusions. These members are layered together after alignment, and are integrated through direct bonding through a heat press. At this time, each of the members are bonded together directly through the bonding protrusions.

[0177] Here the direct bonding is the application of pressure and a heat treatment in a state wherein the surfaces of the two members to be bonded are in intimate contact with each other, and is strong bonding between atoms using the forces between atoms that operate between the surface portions, to enable integration of the surfaces of the two members to each other, without the use of an adhesive agent. At this time, the bonding protrusions achieve the strong bonding. That is, the bonding protrusions are crushed and the bonding surfaces are enlarged to achieve thermal bonding, and the bonding protrusions play a large role in the bonding.

[0178] Next, the coolant is filled through the filling opening provided in a portion of the upper plate 2 or the lower plate 3. After this, the filling opening is plugged to complete the heat transporting unit 1. Note that the filling of the coolant is performed under a vacuum or under a reduced pressure. Filling under a vacuum or under a reduced pressure causes the coolant to be filled in a state wherein the interior space within the heat diffusing portion or the heat transporting portion is under vacuum or under a reduced pressure. When under a vacuum, the vaporization and condensation temperature of the coolant is reduced, and thus there is the benefit of activating the iteration of the vaporization and condensation of the coolant.

[0179] The heat transporting unit 1 is manufactured through the manufacturing process set forth above. Note that the manufacturing process illustrated here is an example, and the manufacturing may be through a different manufacturing process.

[0180] The ability to prevent the propagation of the shearing stresses of the vaporized coolant that diffuses in the vapor diffusing space 5, through the use of the spindle shape (the tapered shape), as illustrated in FIG. 6 and FIG. 7, will be explained using the results of simulations.

[0181] In the simulations, Comparative Example 1 was a case wherein the pores 8 had a straight shape (where the area of opening on the vapor diffusing space 5 side is the same as the area of opening on the coolant return flow space 6 side), Comparative Example 2 was a case wherein the pores 8 had a reverse- spindle shape (where the area of opening on the vapor diffusing space 5 side is larger than the area of opening on the coolant return flow space 6 side), and the example of embodiment was a case wherein the pores 8 had a spindle shape (where the area of opening on the vapor diffusing space 5 side is smaller than the area of opening on the coolant return flow space 6 side).

[0182] FIG. 11 is an explanatory diagram illustrating the structures of the pores in Comparative Example 1, Comparative Example 2, and the example of embodiment. Side views are illustrated for each of the pores. From left to right, FIG. 11 illustrates the Comparative Example 1, the

Comparative Example 2, and the example of embodiment. In all cases, the vapor diffusing space 5 is at the top in FIG. 11, and the coolant return flow space 6 is at the bottom. The pores 8 connect between the vapor diffusing space 5 and the coolant return flow space 6.

[0183] In Comparative Example 1, as is clear from FIG. 11, the area of opening on the vapor diffusing space 5 side is the same as the area of opening on the coolant return flow space 6 side. In Comparative Example 2, the area of opening on the vapor diffusing space 5 side is larger than the area of opening on the coolant return flow space 6 side. In the example of embodiment, the area of opening on the vapor diffusing space 5 side is smaller than the area of opening on the coolant return flow space 6 side.

[0184] The vaporized coolant diffuses along the "diffusion direction" of the dotted arrow in the vapor diffusing space 5, and the condensed coolant flows back along the "return flow direction" of the dotted arrow in the coolant return flow space 6. The simulations were performed using conditions (1) through (7), below:

(1) The diffusion speed of the vaporized coolant was as applied at the right end of the vapor diffusing space.

(2) The vaporized coolant was diffused from the right to the left in FIG. 11.

(3) The condensed coolant flowed back from the left to the right in FIG. 11.

(4) The left end was left free-flowing.

(5) The temperature was a uniform 298.15 K.

(6) The individual simulations were performed at diffusion speeds of the

vaporized coolant being 0 m/s and 20 m/s.

(7) The sizes of the pores were as illustrated in FIG. 11.

[0185] The results of the simulation for the first comparative example are illustrated in FIG. 12. FIG. 12 is an explanatory diagram illustrating the results of the simulation for the first comparative example in the first form of embodiment according to the Present Application.

[0186] In the first comparative example, in the case wherein the diffusion speed of the vaporized coolant was 0 m/s, the vaporized coolant phase and the condensed coolant phase had essentially symmetrical shapes, and there was no interference between them. However, in the case of the diffusion speed of the vaporized coolant being 20 m/s, there was deformation with the interface of the condensed coolant phase being shifted by the shearing stresses from the vaporized coolant. That is, the shearing stresses due to the diffusion of the vaporized coolant were propagated to the coolant return flow space 6, and interfered with the return flow of the condensed coolant. When this type of interference was produced, the speed of the return flow of the condensed coolant was reduced in the coolant return flow space 6, reducing the speed of heat transportation (the efficiency of the heat transportation) in the heat transporting unit 1.

[0187] In this way, when the area of opening of the pores 8 on the vapor diffusing space 5 side was the same as the area of opening on the coolant return flow space 6 side, the heat transport efficiency of the heat transporting unit 1 was reduced.

[0188] Note that in FIG. 12 the region with the light shading is the vaporized coolant phase, and the region with the dark shading is the condensed coolant phase. [0189] The results of the simulation for the second comparative example are illustrated in FIG. 13. FIG. 13 is an explanatory diagram illustrating the results of the simulation for the second comparative example in the first form of embodiment according to the Present Application.

[0190] In the second comparative example, in the case wherein the diffusion speed of the vaporized coolant was 0 m/s, the vaporized coolant phase and the condensed coolant phase had essentially symmetrical shapes, and there was no interference between them. However, in the case of the diffusion speed of the vaporized coolant being 20 m/s, there was deformation with the interface of the condensed coolant phase being shifted by the shearing stresses from the vaporized coolant. That is, the shearing stresses due to the diffusion of the vaporized coolant were propagated to the coolant return flow space 6, and interfered with the return flow of the condensed coolant. When this type of interference was produced, the speed of the return flow of the condensed coolant was reduced in the coolant return flow space 6, reducing the speed of heat transportation (the efficiency of the heat transportation) in the heat transporting unit 1.

[0191] In this way, when the area of opening of the pores 8 on the vapor diffusing space 5 side was greater than the area of opening on the coolant return flow space 6 side, the heat transport efficiency of the heat transporting unit 1 was reduced.

[0192] Note that in FIG. 13 the region with the light shading is the vaporized coolant phase, and the region with the dark shading is the condensed coolant phase.

[0193] Next, in the example of embodiment, in the case wherein the diffusion speed of the vaporized coolant was 0 m/s, the vaporized coolant phase and the condensed coolant phase had essentially symmetrical shapes, and there was no interference between them. Furthermore, in the case wherein the diffusion speed of the vaporized coolant was 20 m/s, there was essentially no change in the phase of the condensed coolant, and it can be said that there was little effect from the vaporized coolant. This indicates that there is essentially no propagation to the coolant return flow space 6 of the shearing stresses from the vaporized coolant. That is, the diffusion of the vaporized coolant does not interfere with the flow of the condensed coolant in the coolant return flow space 6. (Of course, stated conversely, the condensed coolant flowing back in the coolant return flow space 6 does not interfere with the vaporized coolant diffusing in the vapor diffusing space 5.)

[0194] Having the area of opening of the pores 8 on the vapor diffusing space 5 side being less than the area of opening on the coolant return flow space 6 side increases the diffusion speed of the vaporized coolant and the return flow speed of the condensed coolant, and thus improves the heat transport efficiency of the heat transporting unit 1.

[0195] Improving the heat transport efficiency of the heat transporting unit 1 makes it possible for the heat transporting unit 1 to transport at a high speed, to another location, the heat that is removed from the heat-producing body. The heat that is transported at the high-speed is exhausted into an easily exhaustible location, thus making it possible to achieve easily the exhaust of heat from a heat-producing body that is mounted in a device having a complex shape, such as electronic equipment, transportation equipment, industrial equipment, or the like.

[0196] Note that in FIG. 14 the region with the light shading is the vaporized coolant phase, and the region with the dark shading is the condensed coolant phase.

[0197] FIG. 15 is a graph of the results of the simulations of Comparative Example 1,

Comparative Example 2, and the example of embodiment. FIG. 15 is a graph illustrating the results of the simulations in the first form of embodiment according to the Present Application. In FIG. 15, the three graphs are lined up from the top, and, in order from the top, there are the graph in the first comparative example, the graph in the second comparative example, and the graph in the example of embodiment.

[0198] In each of the graphs in FIG. 15, the vertical axis shows the return flow speed of the condensed coolant in the coolant return flow space 6, and the horizontal axis shows the width of the coolant return flow space 6. In each graph, the return flow speed of the condensed coolant when the diffusion speed of the vaporized coolant is 0 m/s is indicated by the dotted line, and the return flow speed of the condensed coolant when the diffusion speed of the vaporized coolant is 20 m/s is indicated by the solid line.

[0199] As is clear from the graphs of the first and second comparative examples, at the diffusion speed of the vaporized coolant of 20 m/s, the return flow speed of the condensed coolant is a value of 0 m/s. That is, the return flow speed of the condensed coolant is extremely slow due to the effects of the shearing stresses by the diffusion of the vaporized coolant.

[0200] On the other hand, as is clear from the graph of the example of embodiment, the return flow speed of the condensed coolant is essentially the same for the case wherein the diffusion speed of the vaporized coolant is 20 m/s as it is when the diffusion speed of the vaporized coolant is 0 m/s. That is, it can be seen that the shearing stresses due to the diffusion of the vaporized coolant do not exert an interference on the return flow of the condensed coolant. Because there is no interference, this increases the diffusion speed of the vaporized coolant and increases the return flow speed of the condensed current, so the heat transport efficiency of the heat transporting unit 1 is high.

[0201] Note that the speed at the right end being low in the graph in the example of embodiment is because of the production of the circulating flow within the interior due to the application of the condition that the right side is in free flow. In an actual heat transporting unit 1, a movement of the coolant between the vapor diffusing space 5 and the coolant return flow space 6 is produced at the right end, and thus there will be no reduction in speed in this way. (Note that in FIG. 12 through FIG. 14, the left end is the same as the right and in FIG. 15.)

[0202] From the simulation results it can be seen that the pores 8 provided in the heat transporting unit 1 in the first form of embodiment enable the movement of the coolant while preventing interference in the coolant between the vaporized coolant that is diffusing in the vapor diffusing space 5 and the coolant that flows back in the coolant return flow space 6.

[0203] The heat transporting unit 1 in the first form of embodiment, as described above, is able to produce movement of the coolant between the vapor diffusing space 5 and the coolant return flow space 6 while separating and preventing interference between the vapor diffusing space 5 and the coolant return flow space 6.

[0204] A second form of embodiment will be explained next.

[0205] In the second form of embodiment, the explanation will be for a case wherein the interference-preventing plate 7 is provided with an opening portion in either a first end portion, which is an end portion corresponding to the first direction, and/or a second end portion, which is the opposite side from the first end portion.

[0206] The heat transporting unit 45, in the same manner as in the first form of embodiment, comprises an upper plate 2, a lower plate 3, an interference-preventing plate 7, and an

intermediate plate 40.

[0207] FIG. 16 is an assembly perspective diagram of a heat transporting unit according to the second form of embodiment according to the Present Application. FIG. 17 is a side sectional diagram of the heat transporting unit in the second form of embodiment according to the Present Application. The heat transporting unit 45 in the second form of embodiment will be explained using FIG. 16 and FIG. 17. FIG. 16 illustrates the members that structure the heat transporting unit 45 from an angle in the disassembled state, and FIG. 17 illustrates the interior of the heat transporting unit 45, formed from layering the members illustrated in FIG. 16, in a state that is viewed from the side.

[0208] The heat transporting unit l⁴ has a rectangular shape having a short direction and a long direction, where the first direction, wherein the vaporized coolant diffuses, is along the long direction. In this first direction, one of the two ends of the heat transporting unit l⁵ is a first end portion 46, and the end portion opposite of the first end portion 46 is a second end portion 48.

[0209] The upper plate 2, the lower plate 3, and the intermediate plate 40 are identical to those explained in the first form of embodiment. A single interference-preventing plate 7 is layered between the upper plate 2 and the intermediate plate 40, and a single interference-preventing plate 7 is layered between the intermediate plate 40 and the lower plate 3. The layering of the two interference-preventing plates 7 forms a vapor diffusing space 5 in the center, in the direction of thickness, of the heat transporting unit 45, and forms coolant return flow spaces 6 at the top and bottom thereof.

[0210] Additionally, grooves 30 provided in the upper plate 2 form the coolant return flow space 6 on the upper plate 2 side, and grooves 30 provided in the lower plate 3 form the coolant return flow space 6 on the lower plate 3 side. Note that the coolant return flow spaces 6 are not formed by the grooves 30 alone, but are formed through the space wherein the interference-preventing plate 7 and the upper plate 2, which includes the grooves 30, face each other (and the space wherein the lower plate 3 and the interference-preventing plate 7 face each other).

[0211] The intermediate plate 40 forms a facing distance between the two interference- preventing plates 7, to form the vapor diffusing space 5.

[0212] Here the interference-preventing plate 7 is provided with an opening portion 47 or 49 in the heat transporting unit 1 and/or the upper plate 2. Note that the heat transporting unit 45 illustrated in FIG. 16 and FIG. 17 is provided with two interference-preventing plates 7, where opening portions 47 and 49 may be provided in each of the two respective interference- preventing plates 7, or an opening portion 47 or 49 may be provided in either one of the two interference plates 7.

[0213] The opening portion 47 connects the vapor diffusing space 5 and the coolant return flow space 6 at the first end portion 46. The opening portion 47 has an area of opening that is larger than the area of opening of one pore 8, to move the vaporized coolant and the condensed coolant between the vapor diffusing space 5 and the coolant return flow space 6.

[0214] Similarly, the opening portion 49, in the second end portion 48, connects the vapor diffusing space 5 and the coolant return flow space 6. The opening portion 47⁶ has an area of opening that is larger than the area of opening of a pore 8, to move the vaporized coolant and the condensed coolant between the vapor diffusing space 5 and the coolant return flow space 6.

[0215] The opening portions 47 and 49 have areas of opening that are larger than those of the pores 8, so when there is more vaporized coolant than there is condensed coolant, the opening portions 47 and 49 easily move the vaporized coolant from the coolant return flow space 6 to the vapor diffusing space 5. Conversely, when there is more condensed coolant then there is vaporized coolant, the opening portions 47 and 49 easily move the condensed coolant from the coolant return flow space 6 to the vapor diffusing space 5 .

[0216] The heat-producing body is disposed, for example, at the first end portion 46.

[0217] The coolant that is filled into the coolant return flow space 6 is vaporized by the heat from the heat-producing body at the first end portion 46. Because of this, the amount of the vaporized coolant will be greater than that of the condensed coolant at the first end portion 46. On the other hand, the vaporized coolant diffuses in the first direction within the vapor diffusing space 5, and when it arrives at the second end portion 48, cools and condenses. Because of this, there tends to be a greater amount of the condensed coolant than the vaporized coolant at the second end portion 48.

[0218] Of course, coolant that condenses part way through the vapor diffusing space 5 is moved to the coolant return flow space 6 through the pores 8. However, part way through the vapor diffusing space 5, the amount of coolant that condenses is small, and there is neither much evaporated coolant nor condensed coolant therein.

[0219] In contrast, at the first end portion 46, in contact with the heat-producing body, there is a large amount of the vaporized coolant, and there tends to be a large amount of the condensed coolant at the second end portion 48, which is furthest from the heat-producing body. The opening portions 47 and 49 efficiently move the vaporized coolant and the condensed coolant between the vapor diffusing space 5 and the coolant return flow space 6, handling the state wherein there is a great deal of both the vaporized coolant and the condensed coolant at the end portion. The opening portions 47 and 49 moving the vaporized coolant and the condensed coolant efficiently improves the heat transport cycle of the heat transporting unit 45. As a result, the heat transporting unit 45 can transport the heat from the heat-producing body at a high speed.

[0220] As described above, the heat transporting unit 45 in the second form of embodiment improves the heat transport efficiency through increasing the speed of movement of the vaporized coolant and of the condensed coolant at the end portion.

[0221] A third form of embodiment be explained next. In the third form of embodiment, a heat transporting unit provided also with a heat radiating portion and a contacting portion will be explained. FIG. 18 is a schematic diagram of electronic equipment in a fourth form of embodiment according to the Present Application. FIG. 18 illustrates a state wherein a heat transporting unit 70 is contained within a case for electronic equipment.

[0222] Electronic equipment 60 is provided with a frame 62 and an electronic circuit board 64 that is contained within the case. A heat-producing body 61 is mounted on the electronic circuit board 64. The heat-producing body 61 is an electronic component that produces heat. This includes, for example, semiconductor integrated circuits, power devices, light-emitting elements, discrete electronic elements, and the like.

[0223] The heat transporting unit 70 makes thermal contact, at a contacting portion 71, with the heat-producing body 61 .

[0224] The heat transporting unit 70 has the same functions and structures as the heat transporting units 1 and 45 explained in Forms of Embodiment 1 through 3⁹.

[0225] The heat-producing body 61 makes thermal contact at a first end portion 65 of the heat transporting unit 70. The heat transporting unit 70 transports, to the second end portion 66, which is the opposite end portion from the first end portion, the heat received from the heat-producing body 61. In this transport, as explained in Forms of Embodiment 1 through 3¹⁰, the vaporized coolant diffuses towards the second end portion 66 from the first end portion 65 through the vapor diffusing space 5, and the condensed coolant in the vapor diffusing space 5 moves through the pores 8 to the coolant return flow space 6. The condensed coolant that has moved to the coolant return flow space 6 flows back towards the first end portion 65 from the second end portion 66 through the coolant return flow space 6. The heat of the heat-producing body 61 is transported from the first end portion 65 to the second end portion 66 through the diffusion of the vaporized coolant and the return flow of the condensed coolant.

[0226] In the electronic equipment 60, often the position wherein the heat-producing body 61 is mounted is far from a position wherein the heat of the heat-producing body 61 can be exhausted. This is because often the structure of the electronic equipment 60 is complex. Moreover, it is often difficult for the electronic equipment 60 to exhaust the heat near to the heat-producing body 61. This is because of the dependency on the state of packaging.

[0227] The heat transporting unit 70, in this way, is used optimally in electronic equipment wherein the position of the heat-producing body 61 is far from the position of the heat exhaust.

[0228] The heat transporting unit 70 has a heat radiating portion 63 that cools the vaporized coolant at the second end portion 66 that is opposite from the first end portion 65 that is in thermal contact with the heat-producing body 61. FIG. 18 illustrates a cooling fan as an example of a heat radiating portion 63.

[0229] The cooling fan cools the second end portion 66 of the heat transporting unit 70. The vaporized coolant that diffuses arrives at the second end portion 66, and the cooling fan cools the vaporized coolant. The cooling of the vaporized coolant causes it to be condensed into the condensed coolant. The condensed coolant passes through the pores 8 and the opening portions 47 and 49 to move from the vapor diffusing space 5 to the coolant return flow space 6.

[0230] In this way, the heat transporting unit 70 having the heat radiating portion 63 makes it possible for the heat transporting unit 70 to cool the vaporized and transported coolant efficiently. Because of this, preferably the heat radiating portion 63 cools the end portion that is opposite of the heat-producing body 61 in the heat transporting unit 70. Cooling the end portion on the opposite side promotes condensation of the vaporized coolant, enabling the heat transporting unit 70 to transport more quickly, along the first direction, the heat that is removed from the heat-producing body 61.

[0231] The heat radiating portion 63 includes a variety of members that can dissipate heat, such as a liquid-cooled jacket, a Peltier element, a heat sink, and the like, in addition to the cooling fan.

[0232] Additionally, the heat transporting unit 70 preferably has a contacting portion 71 that makes thermal contact with the heat-producing body 61. [0233] The contacting portion 71 makes thermal contact easily between the heat-producing body 61 and the heat transporting unit 70. For example, preferably a contacting portion 71 having a thermal interface material (TIM) is used.

[0234] A thermal grease, or a material wherein a filler, or the like, has been added to a thermal grease, may be used as the thermal contact material. These thermal contact materials may be coated on the contacting portion 71.

[0235] The contacting portion 71 using a thermal contact material makes it possible to reduce the thermal resistance with the heat-producing body 61, and, due to the reduced thermal resistance, enables the contacting portion 71 to receive the heat from the heat-producing body 61 easier.

[0236] The heat transporting unit 70 making thermal contact with the heat-producing body 61 included in the electronic equipment 60 causes the heat produced by the heat-producing body 61 to be transported efficiently to a position that is distant from the heat-producing body 61. The result is that the heat-producing body 61 is cooled efficiently. That is, this makes it possible to prevent malfunctions due to heating of the electronic equipment 60.

[0237] Additionally, the heat transporting unit 70 is structured from layering a thin flat upper plate and lower plate, and thus is extremely thin. Because of this, this does not interfere with the miniaturization of the electronic equipment. In particular, the electronic equipment often contains a large number of elements that have a wide area but a small thickness, such as the electronic circuit board 64. Because of this, while there is extra mounting space in the direction of the plane, there is essentially no extra mounting space in the direction of thickness. In this situation, the heat transporting unit 70 is thin and can transport the heat in the direction of the plane, and thus can be applied to cooling of the heat-producing body 61.

[0238] As described above, the heat transporting unit 70 can be housed within the electronic equipment 60 without interfering with the electronic equipment being made smaller and thinner, and can cool the heat-producing body 61 efficiently.

[0239] A mobile device, such as in FIG. 19, is used preferably as an example of the electronic equipment. FIG. 19 is a perspective view of the electronic equipment in the third form of embodiment according to the Present Application.

[0240] Electronic equipment 80 is a mobile terminal that must be thin and small, such as a color television or a personal monitor. [0241] The electronic equipment 80 is provided with a display 83, a light-emitting element 84, and a speaker 85. A heat transporting unit 70 is housed within this electronic equipment 80, to achieve the cooling of the heat-producing body.

[0242] The use of the heat transporting unit 70 of this type makes it possible to cool the heat- producing body without interfering with the electronic equipment being made smaller and thinner. That is, the heat transporting unit 70 can transport, at a high speed, the heat from the heat-producing body, making it possible to prevent the heating of the heat-producing body.

[0243] The heat transporting unit 70 can replace a heat-radiating fin or a liquid cooling device, or the like, that is mounted in a notebook computer, a mobile device, a computer terminal, or the like, can replace cooling equipment mounted in industrial equipment, and can replace heat- dissipating frames and cooling devices that are mounted in control computer units. The heat transporting unit 70 can transfer heat more quickly than a heat pipe that is used conventionally, and thus can increase the cooling capacity. Furthermore, it can also be adapted flexibly to the heat-producing bodies, making it possible to cool a variety of different electronic components. As a result, the heat transporting unit 70 has a broad range of applications.

[0244] Although the heat transporting unit 70 has a flat-plate shape, it is formed from stacked flat plate members, and can be curved or bent as well. In such a case, the return flow of the condensed coolant is through grooves that are separate from the passage wherein the vaporized coolant diffuses through a passage and wherein there is return flow through the capillary passages, and thus the heat transporting unit is able to transport the heat with high efficiency. In particular, the heat transporting efficiency is high because there is no interference between the vaporized coolant and the condensed coolant.

[0245] For example, depending on the shape within the electronic equipment, it may be difficult to mount the heat transporting unit 70 unless it is of a curved shape. In such a case, a curved heat transporting unit 70 may be mounted.

[0246] While a preferred embodiment of the Present Application is shown and described, it is envisioned that those skilled in the art may devise various modifications without departing from the spirit and scope of the foregoing Description and the appended Claims.

Claims

WHAT IS CLAIMED IS: 1. A heat transporting unit, comprising:

an upper plate;

a lower plate, the lower plate facing the upper plate;

an interior space, the interior space being fillable with a coolant and formed by the upper plate and the lower plate;

a vapor diffusing space, the vapor diffusing space disposed in the interior space and being adapted for diffusing a vaporized coolant;

a coolant return flow space, the coolant return flow space disposed in the interior space and being adapted for causing condensed coolant to flow back; and

an interference-preventing plate, the interference-preventing plate being adapted for preventing interference between the vaporized coolant that diffuses in the vapor diffusing space and the condensed coolant that flows back in the coolant return flow space;

wherein:

the interference-preventing plate includes a plurality of pores for moving coolant, that has condensed in the vapor diffusing space, to the coolant return flow space; and

the area of opening in the pore on the vapor diffusing space side is smaller than the area of opening on the coolant return flow space side.

2. The heat transporting unit of Claim 1, wherein the vapor diffusing space and the coolant return flow space are separated by the interference-preventing plate.

3. The heat transporting unit of Claim 2, wherein the vapor diffusing space diffuses a vaporized coolant along a first direction.

4. The heat transporting unit of Claim 3, wherein the coolant return flow space causes a condensed coolant to flow back in a second direction opposite the first direction.

5. The heat transporting unit of Claim 4, wherein the heat transporting unit further comprises a first end portion and a second end portion, the second end portion being opposite the first end portion.

6. The heat transporting unit of Claim 5, wherein a coolant is vaporized by heat of a heat-producing body disposed in the vicinity of the first end portion.

7. The heat transporting unit of Claim 6, wherein the vapor diffusing space diffuses the vaporized coolant along the first direction.

8. The heat transporting unit of Claim 7, wherein the pores move coolant, that has condensed in the process of diffusing from the first end portion to the second end portion, to the coolant return flow space.

9. The heat transporting unit of Claim 8, wherein the coolant return flow space causes the condensed coolant, which has moved to the coolant return flow space, to flow back along the second direction.

10. The heat transporting unit of Claim 9, wherein the pores both cause the fluid that condenses within the vapor diffusing space to move into the coolant return flow space, preventing the propagation of the shearing stresses of the vaporized coolant, that diffuses within the vapor diffusing space, to the coolant return flow space.

11. The heat transporting unit of Claim 10, wherein, by preventing the propagation of the shearing stresses to the coolant return flow space, the interference-preventing plate prevents the vaporized coolant along the first direction from interfering with the return flow of the condensed coolant along the second direction.

12. The heat transporting unit of Claim 11, wherein one of the first end portion or the second end portion is further provided with an opening portion that connects between the vapor diffusing space and the coolant return flow space.

13. The heat transporting unit of Claim 12, wherein the opening portion is provided in the interference-preventing plate, and has an area of opening that is larger than that of a pore.

14. The heat transporting unit of Claim 13, wherein the pore has a shape wherein the cross-sectional area thereof is larger towards the coolant return flow space from the vapor diffusing space.

15. The heat transporting unit of Claim 13, wherein one of the upper plate or the lower plate has a plurality of grooves forming a coolant return flow space.

16. The heat transporting unit of Claim 15, wherein the plurality of grooves follows the second direction.

17. The heat transporting unit of Claim 16, wherein, when the grooves are provided in both the upper plate and the lower plate, a first interference-preventing plate is provided facing the upper plate and a second interference-preventing plate is provided facing the lower plate.

18. The heat transporting unit of Claim 17, wherein one of the vapor diffusing space or the coolant return flow space has a metal plating on the surface thereof.

19. The heat transporting unit of 18, further comprising a heat radiating portion, the heat radiating portion being adapted for cooling the vaporized coolant at a second end portion.

20. The heat transporting unit of Claim 19, further comprising a contacting portion, the contacting portion being adapted for making thermal contact with the heat-producing body at the first end portion.