KR20110103387A - Heat Pipes and Electronics - Google Patents

Abstract

The present invention provides a heat pipe and an electronic device that can efficiently cool a light emitting element disposed at an end, and as a result can be efficiently mounted in a narrow space. The heat pipe includes a single plate or a plurality of intermediate plates 5 and a top plate stacked between the top plate 3, the bottom plate 4 facing the top plate 3, the top plate 3, and the bottom plate 4. 3), the body part 2 formed by lamination of the lower plate 4 and the intermediate plate 5 to encapsulate the refrigerant, a vapor diffusion path 6 through which the vaporized refrigerant can be diffused, and a capillary flow path through which the condensed refrigerant can be refluxed (7), the vapor diffusion path (6) is formed from the first end (15) of the body portion toward the second end (16) facing the first end (15).

Description

Heat Pipes and Electronics {HEAT PIPE AND ELECTRONIC DEVICE}

The present invention relates generally to a heat pipe for cooling a heat pipe, more particularly a heating element.

As the electronic device, an electronic component that is a heating element that generates heat by an electric current flowing inside is used. If the heat generation of the heating element becomes above a certain temperature, there is a problem that operation guarantee cannot be made, and other parts of the electronic device and potentially adversely affect the box. As a result, there is a possibility of degrading electronic performance.

Several proposals have been made for cooling of heating elements, for example, heat pipes having a cooling effect by evaporation and condensation of encapsulated refrigerant have been proposed. In this example, the heat pipe transfers heat from the heating element to the coolant, and the coolant diffuses heat as it vaporizes in contact with the heat. The vaporized refrigerant is condensed by heat radiation, and the condensed refrigerant is refluxed in a continuous closed circulation. Therefore, by this repeated vaporization and condensation, the heat pipe cools the heating element.

Typical examples of heat pipes are described in Japanese Patent No. 3233808 and Japanese Patent Laid-Open No. 11-101585. More specifically, the 808 patent discloses a cooling system for transferring heat from a heating element to a heat radiating member. That is, the 808 patent uses a heating element having a large amount of heat generation as a cooling target even for a simple object such as a semiconductor integrated circuit, and conducts heat from the heating element to the heat receiving portion, the heat conductive element, and the heat radiating portion to cool the heating element. In another category, the 585 application discloses an electronic substrate having a cooling function.

In recent years, in various types of heating elements requiring cooling, heat pipes need to cool not only central processing unit (CPU) and high density semiconductor integrated circuits, but also light emitting elements including light emitting elements (LEDs). In this case, the light emitting element is quite small and is often composed of a group including a plurality of elements. Here, the space in which the light emitting element and the heat pipe are mounted is often a narrow space.

The cooling system disclosed in the 808 patent diffuses heat from the heat receiving portion toward the heat conducting element. Therefore, the cooling system disclosed in the 808 patent needs to arrange the light emitting element on the rear surface of the heat receiving portion. In this case, there is a problem that the light emitting element is hidden in the cooling system member. In order to avoid this, if the cooling system is installed in a substantially vertical direction, there is a problem that the cooling system takes up extra space. This is because the cooling system member extends up, down, left, and right from the light emitting element as the heat diffuses in the radial direction from the light emitting element as a starting point.

Therefore, in order to reduce the mounting space, it is necessary to arrange the light emitting element at the end of the cooling system member. However, in the cooling system disclosed in the 808 patent, there is a problem in that the heat spreading performance from the end to the heat conductive element is low, and the cooling ability is low when the light emitting element is disposed at the end. The same is true of the heat pipes in which the heat receiving portion, the pipe passing the refrigerant vaporized by the heat receiving portion, and the cooling portion cooling the vaporized refrigerant received from the pipe are separate members, irrespective of the cooling system of the 808 patent. That is, in order to reduce the mounting space, even if the light emitting element is to be disposed at the heat receiving end portion, the cooling capacity is not sufficient in the conventional heat pipe and cooling system.

In addition, since the light emitting elements are smaller and disposed in plural numbers than the semiconductor integrated circuit, there is also a problem that the light emitting elements are difficult to be disposed around the center of the heat receiving portion.

In addition, the electronic substrate of the 585 application has a configuration suitable for the diffusion of the vaporized refrigerant and the reflux of the condensation refrigerant, in addition to the plurality of small holes are aligned and easy to arrange the light emitting element at the end, but the small holes are independent. Not. Therefore, the electronic substrate of the 585 application is not suitable for cooling the light emitting element disposed at the end.

As described above, in the conventional heat pipe and cooling system, in order to reduce the mounting space, a small heating element is disposed at the end, and the heating element disposed at the end cannot be cooled with high efficiency. In particular, the conventional heat pipe and cooling system cannot utilize the heat pipe and cooling system entire members (ie, the entire volume) to efficiently cool the heating element disposed at the end portion.

In addition, in light emitting elements such as high-brightness LEDs, in consideration of Fourier's law, it is important to (1) reduce heat flux by diffusing heat efficiently. That is, even if a high heat flux flows into the heat pipe, it is necessary that the heat pipe can continue the cooling function without drying out (a state in which the vaporized refrigerant cannot condense). In addition, (2) a suitable combination with a heat radiating member for cooling the heat transmitted by the heat pipes and thus transmitted is required.

In view of this aspect, in the cooling system of the 808 patent, since the heat exchange plate element is made of a metal plate, the heat spreading effect is insufficient and the heat flux cannot be lowered. As a result, it is difficult to keep the heating element temperature low. In addition, in the heat exchange plate element, heat received from the heat generating element is heat-transmitted in the radial direction according to the temperature gradient, and is not provided as a structure capable of actively introducing heat into the heat transfer path. Therefore, heat cannot be efficiently introduced into the heat transfer path.

The electronic substrate of the 585 application can only transfer heat one-dimensionally. When the amount of heat generated from the heating element reaches 100 W (in high-brightness LEDs, the amount of heat generated may reach 100 W), the refrigerant contained in the electronic substrate may dry out, and cooling of the heating element may not continue. have. Since the diffusion direction and the reflux direction of the refrigerant included in the electronic substrate are one-dimensional, the vaporized refrigerant is difficult to be sufficiently cooled, and dry out is likely to occur.

That is, a cooling mechanism capable of dissipating heat by efficiently diffusing and transferring heat from an electronic component or an electronic device having a small but large heat generation amount is desired. In this case, it is important that there are few elements that hinder heat inflow when heat from the heating element is diffused and transferred. At the same time, it is necessary to efficiently use the casing of the heat pipe to diffuse the vaporized refrigerant, and it is necessary to cool the vaporized refrigerant with high efficiency.

That is, in the cooling of a small light emitting element having a very high heat generation amount, (1) it is easy to mount the light emitting element as a heating element at the end, and (2) the case where it is mounted at the end is not too large, and (3) There are few inhibitors in the diffusion and transfer of the received heat, and (4) the entire heat pipe can be used to diffuse and transfer the heat, and (5) the diffusion of the vaporized refrigerant and the reflux of the condensed refrigerant are three-dimensional throughout the heat pipe. It is necessary to use as an enemy.

In view of these requirements, an object of the present invention is to provide a heat pipe and an electronic device that can efficiently cool a light emitting element disposed at an end portion, and as a result, can efficiently mount a heat generating element in a narrow space. .

In view of the above problems, the heat pipe of the present invention, the top plate; A bottom plate opposite the top plate; Single or plural intermediate plates stacked between the upper and lower plates; A main body portion formed by laminating an upper plate, a lower plate and an intermediate plate and capable of encapsulating a refrigerant; A vapor diffusion furnace capable of diffusing the vaporized refrigerant; And a capillary flow path capable of refluxing the condensed refrigerant, wherein the vapor diffusion path is formed from the first end of the main body toward the second end facing the first end.

The heat pipe of this invention is easy to mount the heat generating body which is a small electronic component, such as a high brightness LED, in an edge part. Moreover, the heat pipe of this invention can spread | diffuse heat efficiently toward the edge part which opposes the said edge part from the edge part in which the heat generating body is mounted. In particular, since the entire heat pipe may be utilized in three dimensions, the diffusion of the vaporized refrigerant and the reflux of the condensed refrigerant may be performed, thereby effectively cooling the vaporized refrigerant.

As a result of this, even when a high-brightness LED or the like having a considerably high heat generation amount is mounted at an end portion, the heat pipe of the present invention can maintain a cooling function without causing dry out or the like.

The structure and manner of construction and operation together with other objects and advantages of the present invention will be best understood by reference to the detailed description in conjunction with the accompanying drawings, in which like reference characters designate like elements:
1 is an inner view of a heat pipe according to Embodiment 1 of the present invention;
2 is a cross-sectional view of the heat pipe of FIG. 1;
3 is an exploded cross-sectional view of the heat pipe of FIG. 1;
4 is an inner view of the heat pipe of FIG. 1;
5 is an internal view of a portion of an electronic device according to the present invention;
6 is an inner view showing a modification of the heat pipe of FIG.
7 is a schematic showing three examples;
8 is a heat pipe surface temperature distribution diagram of Examples 1 to 3 of Case 1;
9 is a heat pipe surface temperature distribution diagram of Examples 1 to 3 of Case 2;
10 is an explanatory diagram showing experimental results;
11 is a perspective view of a heat pipe according to the present invention;
12 is a mounting view of the heat pipe of FIG. 1 having a curved shape;
13 is a mounting view of the heat pipe of FIG. 1;
14 is an exploded view of the heat pipe of FIG. 1;
15 is a perspective view of an electronic apparatus according to the present invention.

While the invention may be embodied in other forms of embodiment, it will be described in detail with the specific embodiments shown in the drawings, which are to be considered as illustrative of the principles of the invention, and it is to be understood that the invention is to be limited only as shown. It should be understood that no. In addition, in the embodiments shown in the drawings, the notation of directions such as up, down, left, right, front, back, etc. is for explaining the structure and movement of the various elements of the present invention and are not absolute but relative. These notations are appropriate when the elements are in the positions shown in the figures. If the elements location description changes, it is to be understood that these notations change accordingly.

According to a first aspect of the present invention, a heat pipe includes: an upper plate; A bottom plate opposite the top plate; Single or plural intermediate plates stacked between the upper and lower plates; A main body portion formed by laminating an upper plate, a lower plate and an intermediate plate and capable of encapsulating a refrigerant; A vapor diffusion furnace capable of diffusing the vaporized refrigerant; And a capillary flow path capable of refluxing the condensed refrigerant, wherein the vapor diffusion path is formed from the first end of the main body toward the second end facing the first end.

By the above configuration, the heat pipe can efficiently diffuse heat from the heat generator disposed at the first end portion to the second end portion. In addition, the heat pipe can use the whole and vaporize refrigerant diffusion and condensation refrigerant reflux, and does not interfere with each other. Therefore, the heat of the heat generating element disposed at the end can be diffused using the entire heat pipe efficiently.

In the heat pipe which concerns on the 2nd aspect of this invention, in addition to a 1st aspect, the width | variety in the 2nd end part of a vapor diffusion path is larger than the width in a 1st end part.

With the above configuration, the vaporized refrigerant can diffuse toward the second end without being disturbed at the first end where the heat generating element is disposed. Thus, the heat spreading capability from the first end to the second end of the heat pipe is improved.

In the heat pipe according to the third aspect of the present invention, in addition to the second aspect, the vapor diffusion path extends from the first end to the second end.

With the above configuration, the vaporized refrigerant can diffuse toward the second end without being impeded at the first end where the heating element is disposed. Thus, the heat spreading capability from the first end to the second end of the heat pipe is improved.

In the heat pipe according to the fourth aspect of the present invention, in addition to the first aspect, the width at the second end of the vapor diffusion path is substantially the same as the width at the first end.

With the above configuration, the vaporized refrigerant can be diffused toward the second end without being impeded at the first end where the heating element is arranged, and can be refluxed without being impaired. That is, the diffusion of the vaporized refrigerant and the reflux of the condensed refrigerant can move in an optimal balance. As a result of this, the heat pipe can diffuse the heat | fever from the heat generating body arrange | positioned at the edge part efficiently.

In the heat pipe according to the fifth aspect of the present invention, in addition to any one of the first to fourth aspects, the intermediate plate has a cutout portion and an inner through hole, and the cutout portion forms a vapor diffusion path, and the inside penetration The ball forms a capillary flow path.

With the above configuration, a vapor diffusion path capable of diffusing the vaporized refrigerant in the plane and thickness directions, and a capillary flow path capable of refluxing the condensation refrigerant in the vertical, vertical, and planar directions can be easily formed even inside the thin heat pipe. Can be.

In the heat pipe according to the sixth aspect of the present invention, in addition to the fifth aspect, there are a plurality of intermediate plates, and only some of the inner through holes provided in each of the plurality of intermediate plates overlap each other, and the cross-sectional area in the horizontal direction of the inner through holes is overlapped. A capillary flow path having a smaller cross-sectional area is formed.

By the above configuration, a capillary flow path having a finer flow path can be easily formed.

In the heat pipe according to the seventh aspect of the present invention, in addition to any one of the first to sixth aspects, each of the upper plate and the lower plate further includes a recess communicating with at least a portion of the capillary flow path and the vapor diffusion path.

By the above configuration, the vapor diffusion path can diffuse the vaporized refrigerant not only in the planar direction but also in the thickness direction. In addition, the surface area in contact with the vaporized refrigerant is increased, and the cooling of the vaporized refrigerant is also promoted. In addition, reflux of the condensed refrigerant into the capillary flow path is also promoted.

In the heat pipe according to the eighth aspect of the present invention, in addition to any one of the first to seventh aspects, the vapor diffusion passage diffuses the vaporized refrigerant in the planar direction and the thickness direction, and the capillary flow passage vertically condenses the refrigerant. Or reflux in the vertical and planar directions.

By the above configuration, the heat pipe can realize heat diffusion with high efficiency from the first end to the second end.

EMBODIMENT OF THE INVENTION Hereinafter, the Example of this invention is described, referring drawings.

In addition, in this specification, a heat pipe is a member, component, and apparatus which realizes the function which cools a heat generating body by repeating cooling of the refrigerant | coolant enclosed in an internal space with heat from a heat generating body, and cooling and condensing a vaporizing refrigerant. Means appliance.

Example 1-Heatpipe Concept Description

First, the heat pipe concept will be described.

The heat pipe is configured such that a surface in which a refrigerant is sealed and heat is received is in contact with a heat generating element including an electronic component. The internal refrigerant receives heat from the heat generating element and vaporizes it, and when evaporated, takes the heat of the heat generating element. The vaporized refrigerant moves (diffuses) the inside of the heat pipe. By this movement, heat of the heating element is transferred. The moved vaporized refrigerant is cooled and condensed on the heat dissipating side of the heat pipe (or by a secondary cooling member such as a heat sink or a cooling fan). The refrigerant condensed and liquefied flows back inside the heat pipe and moves back to the heat receiving surface. The refrigerant moved to the heat receiving surface vaporizes again to receive the heat generating element heat.

According to the repeated vaporization and condensation of the refrigerant as described above, the heat pipe cools the heating element. Therefore, the heat pipe needs to have a vapor diffusion path for diffusing the vaporized refrigerant therein and a capillary flow path for refluxing the condensed refrigerant.

As a heat pipe example, a heat pipe having a tube shape and having a structure for diffusing vaporized refrigerant in a vertical direction and refluxing the condensed refrigerant in a vertical direction, and a heat receiving portion in contact with a heating element and a cooling portion for cooling the refrigerant are separate bodies and connected by pipes. There is a heat pipe that has a structure.

The heat pipes having these structures have a complicated shape for transferring vaporized refrigerant by heat transfer elements such as pipes according to the heat received by the heat receiving portion, and it is difficult to mount the heating element at the end. Therefore, a flat heat pipe is required. However, flat heat pipes also diffuse heat from the center to the periphery, or heat only linearly and one-dimensionally, so that heat from the ends is not dried out for a large heating element. The spread cannot be realized.

The heat pipe of the present invention can mount a heat generating element at an end portion and does not require a mounting space, and can utilize the whole heat pipe in three dimensions to diffuse heat and cool the heat generating element.

Full configuration

First, the whole structure of a heat pipe is demonstrated with reference to FIGS.

FIG. 1 is an internal view of the heat pipe in Embodiment 1 of the present invention, and FIG. 2 is a cross-sectional view of the heat pipe in Embodiment 1 of the present invention.

FIG. 1: shows the figure which looked inside the heat pipe from the top, and FIG. 2 shows sectional drawing observed from the heat pipe edge part.

The heat pipe 1 is composed of an upper plate 3, a lower plate 4, a single or plural intermediate plates 5, a vapor diffusion path 6, and a capillary flow path 7. The lower plate 4 is opposed to the upper plate 3, and the single or plural intermediate plates 5 are laminated between the upper plate 3 and the lower plate 4. The main body part 2 is formed by lamination | stacking and joining of the upper board 3, the lower board 4, and the intermediate board 5, and has the internal space which can enclose the refrigerant | coolant 11. As shown in FIG. The heat pipe 1 can cool the heat generating element by vaporization and condensation of the refrigerant enclosed in the internal space.

The vapor diffusion path 6 is formed by the notch 8, and the capillary flow path 5 is formed by the internal through hole 9.

The vapor diffusion path 6 diffuses the vaporized refrigerant. The vaporized refrigerant diffuses in at least one direction in the planar direction and the thickness direction via the vapor diffusion path 6. In particular, the vapor diffusion path 6 is formed from the upper plate 3 to the lower plate 4, and at least a portion of the vapor diffusion path 6 is provided to at least a portion of the upper plate 3 and the lower plate 4. Since it communicates with the recessed part 12 formed, the refrigerant | coolant which receives the heat from a heat generating body and vaporizes diffuses three-dimensionally along a planar direction and a thickness direction.

As is apparent from FIG. 1, the vapor diffusion path 6 is formed from the first end 15 toward the second end 16. Therefore, the vapor diffusion path 6 diffuses the vaporized refrigerant from the first end 15 toward the second end 16. In other words, the heat pipe 1 has a heat diffusion characteristic from the end portion 15 toward the end portion 16.

The capillary flow path 7 refluxes the cooled, condensed refrigerant. The capillary flow path 7 refluxes the condensed refrigerant in the vertical direction or the vertical and planar directions. That is, the capillary flow path 7 moves the condensed refrigerant three-dimensionally in the same manner as the vapor diffusion path 6. At this time, at least a part of the capillary flow path 7 communicates with a part of the concave part 12 so that the condensed refrigerant moves from the concave part 12 of the upper plate 3 to the capillary flow path 7 or vice versa. Therefore, the refrigerant can also move in the vertical direction. Similarly, since the capillary flow path 7 is formed two-dimensionally in the internal space, the refrigerant can also move in the planar direction. As described above, the capillary flow path 7 also refluxs the condensed refrigerant three-dimensionally.

Further, since the capillary flow path 7 is formed over the first end 15 and the second end 16 so as to match the shape of the vapor diffusion path 6, the capillary flow path 7 is the second end 16. ), The condensation refrigerant is refluxed toward the first end 15.

The diffusion of the vaporized refrigerant and the reflux of the condensed refrigerant proceed between the first end 15 and the second end 16 so that the heat from the heating element disposed at the first end 15 is efficiently cooled. . The heat from the heating element received by the first end 15 diffuses from the first end 15 to the second end 16. Since heat spreads from the first end 15 to the second end 16, this diffusion is as if proceeded using the entire heat pipe 1. In addition, since diffusion is performed three-dimensionally throughout the heat pipe 1, the vaporized refrigerant is easy to cool. This is because the vaporized refrigerant moves using the entire heat pipe 1, and the contact area with the members (upper plate 3, lower plate 4 and side surfaces) connected to the outside becomes wider.

Similarly, the capillary flow path 7 moves the condensed refrigerant from the second end 16 to the first end 15, so that the condensed refrigerant is supplied to the first end 15. Since the capillary flow path 7 is separated from the vapor diffusion path 6, the capillary flow path 7 can reflux the condensed refrigerant without being disturbed by the vapor that diffuses. Therefore, the reflux of the condensed refrigerant also proceeds at a high speed. As a result of this, the condensation refrigerant is repeatedly supplied to the first end portion 15 on which the heating element is arranged.

Particularly in this case, not only the steam diffusion path 6 is formed from the first end 15 toward the second end 16, but also the capillary flow path 7 is adapted to correspond to the vapor diffusion path 6 position. Since it is formed toward the first end 15 from 16, a plurality of vapor diffusion passages 6 and capillary flow passages 7, which may be a plurality of passages, are formed at the first end 15 and the second end 16. It is formed between. Further, as shown in FIG. 1, the vapor diffusion path between the first end 15 and the second end 16 so that one vapor diffusion path 6 and one capillary flow path 7 are adjacent to each other side by side. 6 and the capillary flow path 7 are alternately positioned in parallel to diffuse vaporization refrigerant from the first end 15 to the second end 16 and from the second end 16 to the first end 15. Balance of reflux of condensed refrigerant is achieved. In the cooling of the heating element by the heat pipe, not only the diffusion of the vaporized refrigerant but also the efficient reflux of the condensed refrigerant is required.

From this configuration, a vapor diffusion path 6 and a capillary flow path 7 are formed over the first end 15 and the second end 16 (in particular, a plurality of vapor diffusion paths 6 and a plurality of capillary tubes). Each of the flow paths 7 are alternately formed side by side, and in the first embodiment, the heat pipe 1 can cool the heat generating element disposed at the end with high efficiency. Of course, since the whole heat pipe 1 can be cooled, there is no useless portion and no extra mounting space is required.

In this case, as is apparent from FIG. 1, the heat pipe 1 is thin in shape of a flat plate but may have various shapes such as circular, elliptical, and polygonal. Of course, it can be curved.

In addition, the heat pipe 1 is not specifically limited in size. However, in actual use, it may be appropriate to be within a predetermined size range.

As an example, the heat pipe 1 has a rectangle of 20 mm 20 mm square or 200 mm 200 mm square or more, and has a thickness of 1 mm or more and 5 mm or less. Such predetermined size is determined from the size of the electronic component that is the cooling target heating element, the ease of mounting on the circuit board, and the like. Since the heat pipe 1 has a size mentioned as an example in this case, the mounting and cooling balance can be properly achieved.

Of course, the size of the heat pipe 1) is not limited to this size, and can be determined according to various requirements such as manufacturing requirements, usage requirements, and mounting requirements.

Next, the detailed description of each part is also demonstrated with reference to FIGS. 3 is an exploded sectional view of the heat pipe in Embodiment 1 of the present invention.

In the present case, the first end 15 and the second end 16 are used as " first " and " second " for convenience and are not particularly distinguished. It is only to define the side in which the heating element is arrange | positioned as a 1st.

Top plate

The upper plate 3 is flat and has a predetermined shape and area.

The top plate 3 is formed of metal, resin, or the like, but is formed of metal of high thermal conductivity or high rust resistance (durability) such as copper, aluminum, silver, aluminum alloy, iron, iron alloy, stainless steel, etc. It is preferable. In addition, the top plate 3 may have various shapes such as rectangular, rhombus, circular, elliptical, polygonal and the like.

The upper plate 3 preferably has a concave portion 12 which communicates with at least a portion of the vapor diffusion path 6 and the capillary flow path 7 on one surface facing the intermediate plate 5. Since the concave portion 12 communicates with the capillary flow path 7, condensation refrigerant can be transferred from the upper plate 3 to the capillary flow path 7. On the other hand, since the recessed portion 12 communicates with the vapor diffusion path 6, the vaporized refrigerant easily comes into contact with a large area on the surface of the upper plate 3, and heat dissipation of the vaporized refrigerant is promoted. Further, since the recessed portion 12 communicates with the vapor diffusion path 6, the vaporized refrigerant diffuses not only in the planar direction but also in the thickness direction (vertical direction), and the vaporized refrigerant diffuses in three dimensions.

It is preferable that the upper plate 3 has a protrusion or an adhesive portion to be joined to the intermediate plate 5. The upper plate 3 is called "upper" for convenience; It does not have to be physically in the upper position, nor is it specifically distinguished from the lower plate 4. In addition, the upper plate 3 may be a surface in contact with the heating element, or may be a surface facing the heating element.

In addition, the upper plate 3 may be provided with a coolant injection port 10. When the upper plate 3, the intermediate plate 5, and the lower plate 4 are laminated and joined together, an internal space is formed. Since it is necessary to enclose a coolant in such an internal space, the coolant is filled from the injection port 10 after joining the upper plate 3 or the like. The inlet 10 is filled with a refrigerant and sealed to seal the internal space.

In this case, the coolant may be sealed from the inlet 10 after lamination, and the coolant may be sealed when the upper plate 3, the lower plate 4, and the intermediate plate 5 are laminated.

Bottom plate

The lower plate 4 is interposed with the single or plural intermediate plates 5 while facing the upper plate 3.

The lower plate 4 is made of metal, resin, or the like, but is made of metal of high thermal conductivity or high rust resistance (durability) such as copper, aluminum, silver, aluminum alloy, iron, iron alloy, stainless steel. desirable. In addition, the top plate 3 may have various shapes such as rectangular, rhombus, circular, elliptical, polygonal, etc .; However, since the main body portion 2 is formed while facing the top plate 3, it is preferable to have the same shape and area as the top plate 3.

The lower plate 4 preferably has a concave portion 12 communicating with the vapor diffusion path 6 and the capillary flow path 7 on one surface of the lower plate 4 that faces the intermediate plate 5. Since the concave portion 12 communicates with the capillary flow path 7, the condensed refrigerant is easily transferred from the upper plate 3 to the capillary flow path 7. In contrast, since the concave portion 12 communicates with the vapor diffusion path 6, the vaporized refrigerant easily comes into contact with a large area on the surface of the upper plate 3, and heat dissipation of the vaporized refrigerant is promoted. In addition, since the recess 12 communicates with the vapor diffusion path 6, the vaporized refrigerant diffuses not only in the planar direction but also in the thickness direction (vertical direction), and the vaporized refrigerant diffuses in three dimensions. This has the same meaning as that in which the recessed portion 12 is provided in the upper plate 3.

The lower plate 4 is called "lower" for convenience; It is not physically present at the lower position, and is not particularly distinguished from the upper plate 3.

It is preferable that the lower plate 4 is provided with a protrusion or an adhesive portion to be joined to the intermediate plate 5.

In addition, the lower plate 4 may or may not be in contact with the heating element.

Midboard

The intermediate plate 5 is composed of one or more members. In FIG. 3, the heat pipe 1 has four intermediate plates 5. The intermediate plates 5 are laminated between the upper plate 3 and the lower plate 4.

The intermediate plate 5 is formed of metal, resin, or the like, but is preferably formed of a metal having high thermal conductivity or high rust resistance (durability) such as copper, aluminum, silver, aluminum alloy, iron, iron alloy, or stainless steel. . In addition, the intermediate plate 5 may have various shapes such as rectangular, rhombus, round, oval, or polygonal; Since it forms between the upper board 3 and the lower board 4, and forms the main-body part 2, it is preferable that it is the same shape as the upper board 3 and the lower board 4. As shown in FIG. Also, because of being sandwiched between the upper plate 3 and the lower plate 4, the area of the intermediate plate 5 may be the same as or slightly smaller than the upper plate 3 and the lower plate 4.

In addition, the intermediate plate 5 may have protrusions or adhesive portions used when bonding with the upper plate 3 and the lower plate 4. In addition, the intermediate plate 5 has an internal through hole 9 having a small cross-sectional area. These inner through holes 9 form a capillary flow path 7.

Finally, the intermediate plate 5 is laminated and bonded between the upper plate 3 and the lower plate 4 to form the body portion 2. The number of intermediate plates 5 may be singular or plural. In this case, in order to form the capillary flow path 7 which has a smaller cross-sectional area as follows, it is preferable that the number of the intermediate plates 5 is plural.

Main body  And end

The main body portion 2 is formed by stacking and joining the upper plate 3, the lower plate 4 and the upper plate 3, and the intermediate plate 5 sandwiched between the lower plate 4. The main body part 2 is a part which becomes the basic body of the heat pipe 1. The main body 2 has an inner space, and a refrigerant is sealed in the inner space. In addition, the internal space is provided with a vapor diffusion path 6 and a capillary flow path 7.

That is, the main body part 2 functions as a heat pipe in the heat pipe 1.

The first end 15 is one end of the main body 2, and the second end 16 is located at an end of the position opposite to the first end 15 (that is, on the side opposite to the first end 15). End). The vapor diffusion path 6 is formed toward the second end 16 from the first end 15.

In this case, in the 1st end part 15 and the 2nd end part 16, the "end part" does not mean only the strict cross section of the main body part 2, but refers to the position of the surface part of the main body part 2 surface. That is, the position around the end in the main body 2 is referred to as an end.

In addition, the opposite state knitting between the first end 15 and the second end 16 may be different from that shown in FIG. 1. In the main body 2, even when a metal plate or the like extends or protrudes from the first end 15 or the second end 16, the inner space end of the main body 2 has an extended plate end that protrudes. If not, it may be regarded as an end.

Intermediate Plate, Steam diffusion furnace  And Capillary flow path

Next, the vapor diffusion path 6 and the capillary flow path 7 will be described. The intermediate plate 5 forms a vapor diffusion path 6 for diffusing the vaporized refrigerant in at least one direction in the planar direction and the thickness direction, and a capillary flow path 7 for refluxing the condensed refrigerant in the vertical direction or the vertical and planar directions. do.

First, the vapor diffusion path 6 will be described.

The intermediate plate 5 has a notch 8 and an internal through hole 9.

The notch part 8 forms the vapor diffusion path 6. In the case where the intermediate plate 5 is laminated between the upper plate 3 and the lower plate 4, the cutout portion 8 forms a gap. This gap becomes the vapor diffusion path (6).

In this case, since the notch part 8 forms a gap from the lower plate 4 to the upper plate 3, the vapor diffusion path 6 is formed from the lower plate 4 to the upper plate 3. . In addition, since the vapor diffusion path 6 communicates with the recesses 12 formed in the upper plate 3 and the lower plate 4, the vaporized refrigerant is transferred from the vapor diffusion path 6 to the recesses 12. I can move it. The vaporized refrigerant that has reached the recess 12 can move back to the vapor diffusion path 6. As described above, the vaporized refrigerant diffuses from the first end 15 toward the second end 16 while diffusing not only in the planar direction but also in the thickness direction.

As described above, the vapor diffusion path 6 is formed from the first end 15 to the second end 16. Since the capillary flow path 7 is formed in the portions other than the vapor diffusion path 6, the vapor diffusion path 6 and the capillary flow path 7 are alternately arranged in parallel in the interior of the main body 2, like horizontal stripes. do.

The heat pipe 1 has, as an example, a vapor diffusion path 6 extending from the first end 15 to the second end 16 as shown in FIG. 1. That is, the cross-sectional area of the vapor diffusion path 6 in the planar direction on the second end 16 side is wider than the cross-sectional area of the vapor diffusion path 6 in the plane direction on the first end 15 side. The shape and structure of this vapor diffusion path 6 are determined by the notch part 8 of the intermediate plate 5.

As described above, the heat pipe 1 is formed from the first end 15 to the second by the vapor diffusion path 6 having a shape in which the cross-sectional area is widened from the first end 15 to the second end 16. It has a heat spreading characteristic towards the end 16. In this case in FIG. 1, the vapor diffusion path 6 has an expanded shape towards the end; From the first end 15 to the second end 16, there may be bending and inflection, and there may be a change in cross-sectional area change.

Next, the capillary flow path 7 will be described.

The intermediate plate 12 has an inner through hole 9. The inner through hole 9 is a minute through hole and forms a capillary flow path 7 through which the condensed refrigerant flows. In the case where the intermediate plate 5 has a cutout portion 8 as shown in FIG. 3, an inner through hole 9 is formed in a portion other than the cutout portion 8.

Here, when the intermediate | middle plate 5 is single, the internal through hole 9 provided in the intermediate | middle plate 5 turns into the capillary flow path 7 as it is.

On the contrary, in the case where there are a plurality of intermediate plates 5, only a part of the inner through holes 9 provided in each of the plurality of intermediate plates 5 overlaps, and has a cross-sectional area smaller than the cross-sectional area of the inner through holes 9 in the plane direction. A capillary flow path 7 is formed. As described above, in the case where there are a plurality of intermediate plates 5, since the capillary flow path 7 having a cross-sectional area smaller than the cross-sectional area of the inner through hole 9 itself is formed, the condensed refrigerant in the capillary flow path 7 Can be refluxed more effectively. Since the capillary cross-sectional area is small, liquid movement by capillary phenomenon is promoted.

Here, each of the intermediate plates 5 is provided with a plurality of internal through holes 9. The plurality of inner through holes 9 may form a capillary flow path 7 having a plurality of flow paths.

The inner through hole 9 penetrates from the surface of the intermediate plate 5 to the back side, and the shape may be formed into a circular oval, an ellipse, or a rectangle. Or it may be a slit (slit) shape.

The inner through hole 9 may be formed by excavation, press, wet etching, dry etching, or the like.

When the number of the intermediate plates 5 is plural, the inner through holes 9 are provided in each of the plurality of intermediate plates 5. Here, since the plurality of intermediate plates 5 are laminated so that only a part of these internal through holes 9 overlap each other, the position of the internal through holes 9 should be appropriately lightened for each adjacent intermediate plate 5. (shift) For example, the position of the internal through hole 9 in the predetermined intermediate plate 5 and the position of the internal through hole 9 in the other intermediate plate 5 adjacent to the intermediate plate 5 may be defined as the internal through hole ( 9) Only part of the cross section is moved to overlap. As described above, when the plurality of intermediate plates 5 are laminated by the position of the inner through holes 9 in each adjacent intermediate plate 5 being cross-sectional area in the planar direction of the inner through holes 9. A capillary flow path 7 having a smaller cross-sectional area is formed.

When the plurality of intermediate plates 5 are stacked, the capillary flow path 7 is configured so that a part of the inner through holes 9 overlap, and has a cross-sectional area smaller than the cross-sectional area in the planar direction of the inner through holes 9. Holes having a cross-sectional area smaller than the cross-sectional area of the inner through hole 9 are stacked in the vertical direction of the heat pipe 1, and the holes in the vertical direction are connected to each other, so that a vertical flow path is formed. In addition, since a stepped hole is formed in the vertical direction, a flow path that can flow not only in the vertical direction but also in the planar direction is formed. The flow paths formed in these vertical and planar directions are considerably smaller in cross section and reflux the condensed refrigerant in the vertical direction or in the vertical and planar directions. Moreover, since the capillary flow path 7 communicates with the recessed part 12, the refrigerant | coolant cooled and condensed in the recessed part 12 moves from the recessed part 12 to the capillary flow path 7, and it is a capillary tube as it is. It is refluxed through the flow path (7). Thus, since the recessed part 12 and the capillary flow path 7 communicate, the reflux of a condensation refrigerant | coolant is accelerated | stimulated.

In addition, when a part of the inner through hole 9 is formed so as to overlap and a capillary flow path 7 having a smaller cross-sectional area than the inner through hole 9 is formed, the capillary flow path 7 is not directly processed. There is also an advantage that can be easily produced.

In addition, although the capillary flow path 7 refluxs the condensed refrigerant, it is also possible to pass the vaporized refrigerant.

In addition, it is preferable that the capillary flow path 7, the corner part of the recessed part 12, or the corner part of the notch part 8 is chamfered or rounded. The cross section of the capillary flow path 7 may have various cross-sectional shapes such as hexagon, circle, oval, rectangle, polygon, and the like. The cross-sectional shape of the capillary flow path 7 is determined according to the shape of the inner through hole 9 and the superposition method between the inner through holes 9. The cross sectional area is also determined in the same manner.

Manufacturing process

Next, the heat pipe (1) manufacturing process is demonstrated.

The upper plate 3, the lower plate 4, and the intermediate plate 5 are laminated and joined to form a heat pipe 1.

The manufacturing process will be described with reference to FIG. 3.

Each of the upper plate 3, the lower plate 4 and the plurality of intermediate plates 5 (four intermediate plates 12 in FIG. 3) are aligned at positions that can overlap at the same position. In addition, the plurality of intermediate plates 12 are aligned at positions where only a part of each of the inner through holes 9 provided in each of the plurality of intermediate plates 5 can overlap.

At least one of the upper plate 3, the lower plate 4 and the plurality of intermediate plates 5 has a joining protrusion.

The top plate 3, the bottom plate 4 and the plurality of intermediate plates 5 are arranged, aligned and laminated, and are directly joined by a heat press and integrated. At this time, each member is directly joined by the joining protrusion.

Here, direct bonding refers to pressure heat treatment in which the surfaces of two members to be joined are in close contact, and strongly bonds between atoms based on the force between atoms acting between the surfaces, without using an adhesive. It is possible to integrate the faces of the two members. At this time, the bonding projection achieves strong bonding.

As a condition of direct bonding in a heat press, the press pressure is preferably in the range of 40 kg / cm 2 to 150 kg / cm 2 and the temperature is in the range of 250 to 400 ° C.

Next, the refrigerant is injected through the injection hole 10 provided in the upper plate 3 or the lower plate 4. After that, the injection port 10 is sealed and the heat pipe 1 is completed. In this case, the refrigerant filling is carried out under vacuum or reduced pressure. Under vacuum or reduced pressure, the internal space of the heat pipe 1 is in a vacuum or reduced pressure state to fill the refrigerant. Under reduced pressure, there is an advantage that the vaporization and condensation temperature of the refrigerant is lowered, and the repeated vaporization and condensation of the refrigerant is activated.

Behavior description

Next, the operation of the heat pipe 1 will be described.

4 is an inner view of a heat pipe in Embodiment 1 of the present invention. The heat pipe 1 of FIG. 4 is provided with the vapor diffusion path 6 and the capillary flow path 7 of the same shape as FIG. A plurality of heat generators 20 are disposed at the first end 15 of the body portion 2.

Here, the heat generating body 20 is a small brightness | luminance high brightness LED etc. of a large heat generating amount. In the high-brightness LED, a plurality of elements are often used, such as an electric decoration or a headlamp of an automobile, and as shown in FIG. 4, a plurality of heating elements 20 are often disposed at the first end 15.

Each of the heating elements 20 arranged at the first end 15 generates heat. The heat pipe 1 receives heat from the heat generator 20 using the upper plate 3 or the lower plate 4 at the first end 15. The refrigerant vaporizes at the first end portion 15 by the heat sequence. When the refrigerant vaporizes, the heat of the heat generator 20 is deodorized. The vaporized refrigerant diffuses the vapor diffusion path 6 in the plane and thickness directions. Since the vapor diffusion path 6 is formed to extend from the first end 15 to the second end 16 as shown in FIG. 4, the vaporized refrigerant diffuses toward the second end 16 at high speed. do.

The vaporized refrigerant diffuses into the vapor diffusion path 6 and contacts the upper plate 3 and the lower plate 4 in a large area including the recesses 12 and the like due to the diffusion. Although not shown in FIG. 4, the vaporized refrigerant is cooled by a fin, a cooling fan, a liquid cooling jacket, or the like provided around the surface of the heat pipe 1 or around the second end 16. Upon cooling, the vaporized refrigerant condenses. The condensed refrigerant flows back from the second end 16 through the capillary flow path 7 in the vertical, vertical, and planar directions. Once refluxed, the condensed and liquefied refrigerant again reaches the first end 15. The refrigerant reaching the first end 15 vaporizes heat again from the heating element 20 and vaporizes, and the vaporized refrigerant diffuses from the first end 15 to the second end 16 through the vapor diffusion path 6. do.

As described above, in the heat pipe 1 according to the first embodiment, the plurality of vapor diffusion paths 6 and the capillary flow paths (from the first end 15 to the second end 16 of the main body part 2 ( 7) alternately arranged in parallel. Further, the cross-sectional area of the vapor diffusion path 6 at the second end 16 is wider than the cross-sectional area of the vapor diffusion path 6 at the first end 15 where the heating element is disposed, so that the vaporized refrigerant The diffusion rate is faster. One example of the vapor diffusion path 6 is a vapor diffusion path 6 having an expanded shape from the first end 15 to the second end 16, as shown in Figs.

The capillary flow path 7 is formed in a region other than the vapor diffusion path 6 formed. According to the researches of the inventors, in cooling of the heating element resulting from thermal diffusion and thermal diffusion from end to end, it is preferable to balance the diffusion rate of the vaporized refrigerant while giving priority to the reflux of the condensation refrigerant. Therefore, by the vapor diffusion path 6 and the capillary flow path 7 of the shapes shown in FIGS. 1 and 4, the heat pipe 1 gives priority to diffusion of the vaporized refrigerant over reflux of the condensed refrigerant. In the vapor diffusion path 6 having an expanded shape from the first end 15 to the second end 16, which is the arrangement position of the heating element, the moving space of the vaporized refrigerant is moved from the first end 15 to the second end 16. The vapor diffusion path 6 is likely to diffuse the vaporized refrigerant because it gradually widens over the gap. As a result, the diffusion rate of the vaporized refrigerant is increased, and the heat pipe 1 is excellent in thermal diffusion and cooling of the heating element arranged at the first end 15.

In addition, since the cooling ability of the heating element disposed at the end is excellent, there is an advantage that an extra mounting space is not required in an electronic device including a heat pipe. 5 is an internal view of a part of the electronic apparatus according to the first embodiment of the present invention. In FIG. 5, a part of projection part, such as a projector, is shown, for example.

The electronic device 30 includes a box 33, a control device 31, a projection lens 32, and a heating element 20 and a heating element 20, which are light emitting elements that project light onto the projection lens 32. Is further provided with a heat pipe (1) for cooling. The heat generating body 20 is disposed at the first end 15 of the heat pipe 1.

Since the lens 32 needs to receive light from the light emitting element which is the heat generating body 20, it is preferable that the heat generating body 20 is arranged on the substantially centerline of the lens 32. As shown in FIG. In addition, since the controller 31 needs to perform various kinds of control based on the light or the image received from the lens 32, the controller 31 needs to face a part of the lens 32. have. Therefore, as shown in Fig. 5, in the region facing the lens 32, a space for mounting the heating element 20 and the control device 31 is required.

In the present case, if the heat pipe for cooling the heating element 20 is of the type of heat diffusion from the center to the periphery, or of a type having a form divided into a heat receiving portion and a heat conducting portion, in the region facing the lens 32, Heat pipes take up a lot of mounting space. If so, the mounting area of the control device 31 is insufficient or adversely affects the projection to the lens 32.

On the contrary, since the heat pipe 1 can spread | diffuse heat from the 1st end part 15 to the 2nd end part 16 in Example 1, the heat generating body 20 is arrange | positioned at the 1st end part 15. FIG. can do. As a result, when the heating element 20 is almost on the center line of the lens 32, the first end 15 of the heat pipe 1 may also exist in a similar position. That is, as shown in Fig. 5, the heat pipe 1 only needs space for mounting below the centerline of the lens 32.

As described above, in the first embodiment, the heat pipe 1 has an advantage of not requiring an extra mounting space when mounted on an electronic device.

Variant

Next, a modification of the heat pipe 1 will be described. Fig. 6 is an inner view showing a modification of the heat pipe in the first embodiment of the present invention.

In the heat pipe 1 shown in FIG. 6, the width of the vapor diffusion path 6 at the first end 15 and the width of the vapor diffusion path 6 at the second end 16 are substantially the same. In addition, the vapor diffusion path 6 may have the same width from the first end 15 to the second end 16.

Also in this case, the heat pipe 1 has a heat spreading characteristic from the first end 15 to the second end 16. In addition, the capillary flow path 7 is formed in portions other than the vapor diffusion path 6. In addition, the vapor diffusion path 6 may be curved from the first end 15 to the second end 16, have a bent portion, or may have some difference in width. As described above, based on the vapor diffusion path 6 and the corresponding capillary flow path 7 of substantially the same width from the first end 15 to the second end 16, the heat pipe 1, The heat spreading property from the first end 15 to the second end 16 is excellent. As a result, it is possible to cool in a state where a small, high heat generating element such as a high-brightness LED or the like is arranged at the end.

As described above, the heat pipe 1 (including the modification) in Example 1 satisfies all of the following points. (1) It is easy to mount the light emitting element which is a heating element at the end. (2) Even if it mounts to the edge part, it does not occupy too much mounting space as a whole. (3) Inhibitors are small in the diffusion and transfer of heat (the entire heat pipe 1 is used to diffuse the vaporized refrigerant and reflux the condensed refrigerant, and heat does not need to be conducted to individual members such as pipes along the way. because). (4) The entire heat pipe can be used to diffuse and transport heat (consisting of a vapor diffusion path (6) and a capillary flow path (7) throughout the heat pipe, the vapor diffusion path (6) and a capillary flow path) (7) is arranged to be balanced). (5) The diffusion of the vaporized refrigerant and the reflux of the condensed refrigerant proceed in three dimensions using the entire heat pipe. (Because the vapor diffusion path 6 diffuses the vaporized refrigerant in the plane and thickness directions, and the capillary flow path 7 refluxs the condensed refrigerant in the vertical, vertical, and planar directions).

As a result, unlike the prior art, it is possible to arrange and cool a heating element which is particularly small and has a limited placement position, such as a light emitting element.

In addition, the heat pipe 1 is provided with the vapor-diffusion path 6 and the capillary flow path 7 which are alternately arrange | positioned in the main-body part 2, Even when several heat generating bodies 20 are arrange | positioned, Each of the heating elements 20 can be cooled.

Example 2

Next, Example 2 will be described.

In Example 2, the experimental result regarding the superiority of the heat pipe 1 is demonstrated.

The inventors experimented with the shapes of the vapor diffusion path 6 and the capillary flow path 70 provided in the heat pipe 1 to determine which shape is optimal.

The inventors ran simulations on the heat pipes of Examples 1-3. According to this simulation result, what kind of shape of heat pipe was optimal was examined. 7 is a schematic diagram representing three examples. In FIG. 7, Example 1, Example 2, and Example 3 are shown from the left.

Example 1

The heat pipe 40 of Example 1 has a vapor diffusion passage 6 in which the width gradually narrows from the first end 15 to the second end 16 and a corresponding capillary flow passage 7 (first end). The capillary flow path 7 which gradually widens from 15 to the 2nd end 16 is provided.

Example 2

In the same manner as shown in FIG. 1, the heat pipe 41 of Example 2 is a vapor diffusion path 6 which gradually widens from the first end 15 to the second end 16 and corresponding thereto. The capillary flow path 7 (capillary flow path 7 which becomes narrow gradually from the 1st end part 15 to the 2nd end part 16) is provided. That is, the heat pipe 41 is equipped with the vapor diffusion path 6 which is wider in the 2nd end part 16 than the width in the 1st end part 15. As shown in FIG.

Example 3

In the same way as shown in FIG. 6, the heat pipe 42 of Example 3 extends from the first end 15 to the second end 16 with the same steam diffusion path 6 and the corresponding width. The capillary flow path 7 (capillary flow path 7 of the same width from the 1st end 15 to the 2nd end 16) is provided. That is, the heat pipe 42 is provided with the vapor diffusion path 6 and the capillary flow path 7 which the width | variety in the 1st edge part 15 and the width | variety in the 2nd edge part 16 are substantially the same.

In all the heat pipes of Examples 1-3, the vapor diffusion path 6 and the capillary flow path 7 are formed such that heat diffusion is directed from the first end 15 to the second end 16.

Experimental conditions

It carried out under the following experimental conditions.

Heat source: A heat source having a size of 2 X 7 mm is disposed about the center of the first end 15

Thermal bonding agent: thermal grease (PA-080 manufactured by INEX Co., Ltd.) is used

Heat dissipation: The heat dissipation side is forced air cooling by spot cooler (Crisp manufactured by Daikin Industries, Ltd.)

Top surface temperature distribution measurement: Top surface temperature distribution measurement by thermography (TVS-200 manufactured by Nippon Avionics Co., Ltd.)

Heater output of heat source: carried out in two cases

Case 1: Heat equivalent to the heat output of a high-brightness LED mounted at 1W (= 1MW / ㎡)

Case 2: Discharge to Ts = 90 ° C.

Comparative object: Examples 1-3 In order to grasp the temperature change state of the heat pipe, the copper plate is set as the comparison object.

Under the above conditions, the heat source was disposed almost at the center of the first end 15 of the heat pipe of each of Examples 1-3 and the heat diffusion state was measured.

FIG. 8 is a temperature distribution diagram of the heat pipe surface of Example 1-3 of Inventive Example 2 in Case 1. FIG. 8 shows the temperature state of the heat pipe surface measured by the simulation in Case 1. FIG. Also, in order to confirm the temperature distribution of the heat pipes of Examples 1-3, the copper plate is set as a comparison object.

As is apparent from FIG. 8, in contrast to the copper plate as a comparative example, the Example 1-3 heat pipes have a small difference in temperature and ambient temperature near the center, and the Example 1-3 heat pipes have a high heat diffusion capability.

In addition, among the three examples, the heat pipe 40 of Example 1 appears to have the most constant surface temperature. However, in the case of the experimental results of Case 2, it is considered that it is dry out, and as a result, the temperature appears to be constant or low.

9 is a temperature distribution diagram of the heat pipe surface of Example 1-3 of Example 2 of the present invention in Case 2. FIG.

As apparent from Fig. 9, the upper surface temperature of the heat pipe 40 of Example 1 is low, and it is considered that this is drying out. That is, the refrigerant vaporizes but cannot condense, and cannot reach the upper surface of the heat pipe 40 (i.e., the vaporized refrigerant containing heat remains in the interior space, and the heat cannot reach the upper surface, Cotton temperature is thought to be abnormally low). This is considered to be a suitable result even if the upper surface temperature is lower than that of the copper plate as a comparative example.

On the other hand, in each of the heat pipes 41 and 42 of Examples 2 and 3, the difference in the upper surface temperature is not so large, as is also apparent from FIG. Moreover, since the temperature of a heat source part is higher than surroundings, the copper plate which is a comparative example does not spread | disperse heat sufficiently. On the contrary, since the heat distribution of the heat pipes of Examples 1 and 2 is constant, heat is sufficiently diffused.

Next, in Fig. 10, a plurality of samples are produced for each of Examples 1-3, and the result regarding how much the temperature decrease in the center of the upper surface becomes as compared with the copper plate. FIG. 10 is an explanatory diagram showing experimental results in Example 2. FIG.

As is apparent from FIG. 10, the effect of Example 1 is low, but the effect of Examples 2 and 3 is high. Comparing Examples 2 and 3, the effect of Example 3 is slightly higher, and when the heating element is disposed at the first end 15, it is also considered that the heat pipe 42 shown in Example 3 is optimal. However, the difference from Examples 2 and 3 is not large, and either the heat pipe 41 of Example 2 or the heat pipe 42 of Example 3 may be used according to the characteristics of the heating element to be cooled.

As described above, in the cooling of the heating element disposed at the end from the above experiment, the vapor diffusion path 6 having a shape that gradually widens or has substantially the same width from the first end 15 to the second end 16. And it turns out that the heat pipe which has the capillary flow path 7 corresponding to the shape of the vapor diffusion path 6 is suitable.

Example 3

Next, Example 3 will be described.

Fig. 11 is a perspective view of a heat pipe in Embodiment 3 of the present invention. In Example 3, the heat pipe is curved.

The heat pipe 50 having a curved shape is laminated between the curved upper plate 51, the curved lower plate 52 facing the upper plate 51, the upper plate 51 and the lower plate 52. At the same time, a main body portion 54 having a single or a plurality of curved intermediate plates 53 forming at least a portion of the vapor diffusion passage and the capillary flow passage is provided. 11 shows an external perspective view of the heat pipe 50, so that the inside thereof is not visible. Therefore, although the vapor diffusion path and the capillary flow path cannot be shown in FIG. 11, the inside of the main body portion 54 has a vapor diffusion path and the capillary flow path formed as described in the first embodiment.

As is apparent from FIG. 11, the main body portion 54 has a curved shape as a whole. As described above, the heat pipe 50 having a curved shape can be easily mounted even in a narrow space or a complicated space.

For example, as shown in FIG. 12, the heat pipe 50 which has a curved shape can utilize the curved shape, and can cool the heat generating body 55 which exists in the position which is difficult to arrange | position. 12 is a mounting diagram of a heat pipe having a curved shape in Embodiment 3 of the present invention.

If the heating element 55 is disposed at the first end of the heat pipe 50, the heat pipe 50 diffuses heat from the first end to the second end (arrow in the figure). The fan 58 blows air with respect to a 2nd end, and cools a 2nd end. Since the second end is cooled, the vaporized refrigerant condenses, and the condensed refrigerant is refluxed from the second end to the first end (in the opposite direction to the arrow in the figure).

As described above, since the heat pipe 1 described in Example 1 is replaced with the curved heat pipe 50, even in a mounted state in which it is difficult to arrange the heating element 55 or the heat pipe, the heat pipe 50 is provided at the end portion. The heating element 55 arranged can be cooled.

In the present case, the state in which the heat pipe 55 is difficult to mount is, for example, when the mounting substrate or the other device 56 exists next to the heat pipe 55, as shown in FIG. Fig. 13 is a mounting diagram of a heat pipe having a curved shape according to the third embodiment of the present invention.

Next, the heat pipe 50 which has a curved shape is demonstrated in detail.

14 is an exploded view of a heat pipe in Embodiment 3 of the present invention. With reference to FIG. 14, the heat pipe 50 which has a curved shape is demonstrated in detail.

Between the curved top plate 51 and the curved bottom plate 52, the curved intermediate plate 53 is inserted and laminated. The intermediate plate 53 has a cutout portion 60 and an inner through hole 61, the cutout portion 60 forms a vapor diffusion path 64, and the inner through hole 61 has a capillary flow path. Form 65. In addition, at least a part of the upper plate 51 and the lower plate 52 has a recess 62.

At least one of the upper plate 51, the lower plate 52 and the intermediate plate 53 has a protrusion 63, and when the upper plate 51, the lower plate 52 and the intermediate plate 53 are joined, The projection 63 functions as an adhesive. If they are joined using the projections 63, such as an adhesive, a body portion 54 having a curved shape is formed, and a vapor diffusion path 64 and a capillary flow path 65 are formed therein. As described above, since the curved upper plate 51, the lower plate 52 and the intermediate plate 53 are joined, a heat pipe 50 having a curved shape is formed. The heat pipe 50 encloses a refrigerant inside, the vaporized refrigerant diffuses into the main body portion 54 via the vapor diffusion path 64, and the condensed refrigerant is refluxed through the capillary flow path 65. . By repeated vaporization and condensation of the refrigerant, the heat pipe 50 having a curved shape can cool the heating element.

As described above, the curved upper plate 51, the lower plate 52, and the intermediate plate 53 are laminated and bonded to obtain a heat pipe 50 having a curved shape.

Except for the curved shape, the upper plate 51, the lower plate 52, and the intermediate plate 53 have the same structure and function as those described in the first embodiment.

As described above, the heat pipe having excellent heat spreading from the first end to the second end may have a curved shape, and the heating element disposed at the end may be used while utilizing the advantage of increasing flexibility in mounting due to the curved shape. It has the advantage that the cooling is excellent.

Example 4

Next, Example 4 will be described.

In Example 4, the electronic device which mounts the heat pipe described in Examples 1-3 is demonstrated.

An example of an electronic device is shown in FIG. 15. Fig. 15 is a perspective view of an electronic device according to a fourth embodiment of the present invention. The electronic device 82 is an electronic device that is required to be thin and small, such as a vehicle television and a personal monitor.

The electronic device 82 includes a display 83, a light emitting element 84, and a speaker 85. The heat pipe 1 is stored inside such an electronic device 82 to cool the heating element.

The above-mentioned heat pipe 1 can be used to realize cooling of the heating element without hindering miniaturization and thinness of the electronic device. In particular, the heat pipe 1 can cool the heating element mounted at an end portion such as an LED required for the display 83. Therefore, the heat pipe 1 can be mounted without the need for cooling performance and extra mounting space.

From this point of view, the heat pipe 1 is replaced by a heat dissipation fin or a liquid cooling device mounted in a notebook personal computer, a portable terminal, a computer terminal, or the like, or used in a light, engine, control computer portion of an automobile or industrial device. The mounted heat dissipation frame, the cooling device, or the like can be preferably replaced. Since the heat pipe 1 has a higher cooling capacity than the heat radiating fin and the heat radiating frame which are conventionally used, miniaturization can be achieved. Furthermore, it can be applied flexibly to the heating element, and various electronic components can be targeted for cooling. As a result of this, the heat pipe 1 has a wide application range.

In addition, it is to be understood that the heat pipes and electronic devices described in Examples 1 to 4 are examples illustrating the scope of the present invention, and include modifications and variations within the scope of the present invention.

While preferred examples of the invention are shown and described, those skilled in the art will be able to devise various modifications without departing from the spirit and scope of the description and the appended claims.

Claims (19)

Top plate;
A bottom plate opposite the top plate;
Single or plural intermediate plates stacked between the upper and lower plates;
A main body portion formed by laminating an upper plate, a lower plate and an intermediate plate and capable of encapsulating a refrigerant;
A vapor diffusion furnace capable of diffusing the vaporized refrigerant;
A capillary flow path capable of refluxing the condensation refrigerant,
The steam diffusion path is formed from the first end of the main body portion toward the second end facing the first end. The heat pipe according to claim 1, wherein the width at the second end of the vapor diffusion path is wider than the width at the first end. The heat pipe of claim 2, wherein the vapor diffusion path extends from the first end to the second end. The heat pipe according to claim 3, wherein the intermediate plate has a cutout portion and an inner through hole, the cutout portion forms a vapor diffusion path, and the inner through hole forms a capillary flow path. The heat pipe according to claim 4, wherein the number of the intermediate plates is plural, and the inner through holes provided in each of the plurality of the intermediate plates overlap only a part of the caps, and a capillary flow path having a cross-sectional area smaller than the cross-sectional area in the horizontal direction of the inner through holes is formed. . The heat pipe according to claim 5, wherein each of the upper plate and the lower plate further includes a recess communicating with at least a portion of the capillary flow passage and the vapor diffusion passage. The heat pipe according to claim 6, wherein the vapor diffusion path diffuses the vaporized refrigerant in the planar direction and the thickness direction, and the capillary flow path refluxs the condensed refrigerant in the vertical, vertical, and planar directions. The heat pipe according to claim 7, wherein the heat generating element is mountable at the first end, and is capable of diffusing heat of the heat generating element from the first end to the second end. The heat pipe according to claim 1, wherein the width at the second end of the vapor diffusion path is about the same as the width at the first end. The heat pipe according to claim 9, wherein the intermediate plate has a cutout portion and an inner through hole, wherein the cutout portion forms a vapor diffusion path, and the inner through hole forms a capillary flow path. 11. The heat pipe according to claim 10, wherein the number of the intermediate plates is plural, and the inner through holes provided in each of the plurality of intermediate plates overlap only a part, and a capillary flow path having a cross-sectional area smaller than the cross-sectional area in the horizontal direction of the inner through holes is formed. . The heat pipe according to claim 11, wherein each of the upper plate and the lower plate further includes a recess communicating with at least a portion of the capillary flow passage and the vapor diffusion passage. The heat pipe according to claim 12, wherein the vapor diffusion path diffuses the vaporized refrigerant in the planar direction and the thickness direction, and the capillary flow path refluxs the condensed refrigerant in the vertical, vertical, and planar directions. The heat pipe according to claim 13, wherein the heat generating element is mountable at the first end, and is capable of diffusing heat of the heat generating element from the first end to the second end. The heat pipe according to claim 1, wherein the intermediate plate has a cutout portion and an inner through hole, the cutout portion forms a vapor diffusion path, and the inner through hole forms a capillary flow path. 16. The heat pipe according to claim 15, wherein the number of the intermediate plates is plural, and the inner pipes provided in each of the plurality of intermediate plates are partially overlapped, and a capillary flow path having a cross-sectional area smaller than the cross-sectional area of the inner through-hole horizontal direction is formed. . The heat pipe according to claim 16, wherein each of the upper plate and the lower plate further includes a recess communicating with at least a portion of the capillary flow passage and the vapor diffusion passage. 18. The heat pipe according to claim 17, wherein the vapor diffusion path diffuses the vaporized refrigerant in the planar direction and the thickness direction, and the capillary flow path refluxs the condensed refrigerant in the vertical, vertical, and planar directions. 19. The heat pipe according to claim 18, wherein the heat generating element is mountable at the first end and can diffuse the heat of the heat generating element from the first end to the second end.

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