JP2007100992A - Flexible heat pipe and method of manufacturing it - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a flexible heat pipe having flexibility and preventing fluctuation of a pressure in a container even when it is relatively frequently bent, and excellent in reliability, and also to provide a method of manufacturing it. <P>SOLUTION: The flexible heat pipe is provided with: an operating fluid; a flow passage body 11 having a vapor flow passage 12 of the operating fluid and a capillary tube flow passage 13; and a container 16 for enclosing the operating fluid and the flow passage body 11. The container 16 is in a hollow shape having one closed end in a predetermined region of both ends, and comprises a laminated metal tube 17 equipped with: a first metal tube 19 which is thin and flexible; and a second metal tube 20 which is thicker than the first metal tube 19 and rigid. An intermediate part 18 of the container 16 is provided with: the first metal tube 19; and a resin film 21 formed on an outer surface of the first metal tube 19. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

  The present invention relates to a flexible heat pipe that has flexibility and can be bent repeatedly and a method for manufacturing the same.

  In recent years, the development of electronic devices for information communication has been remarkable, and in particular, personal computer-related devices have been miniaturized at the same time as higher performance, and countermeasures against heat radiation are important due to the increase in heat generation and heat generation density due to miniaturization. It has become a challenge. Also, the use of semiconductor lasers for optical disks and the like has become common, and it is also required to efficiently cool such semiconductor lasers.

  Conventionally, cooling of personal computers, particularly CPUs, has been performed using heat pipes. This heat pipe usually uses a container made of a metal pipe such as copper. However, a metal pipe container is inflexible and has a low degree of freedom in shape. For this reason, when it is used for an electronic device that is small and mounted at a high density, the arrangement is restricted, and it is difficult to install the electronic device at an optimal position.

  On the other hand, a flexible sheet-like heat pipe has been proposed (see, for example, Patent Document 1). The proposed heat pipe has a configuration as shown in FIG. FIG. 5 is a cross-sectional view of the heat pipe in the width direction.

  In the sheet-like heat pipe 61, a working fluid (not shown) is enclosed in a sheet-like container 64 made of an elongated film formed by bonding two films 62 such as metal foils with a sealant layer 63. In addition, the inside of the sheet-like container 64 is partitioned into a plurality of vapor channels 66 by a plurality of spacers 65, and a capillary channel 67 for refluxing the working fluid is formed on the upper and lower surfaces of each vapor channel 66. Become. The sheet-like heat pipe 61 is used with one end portion in the longitudinal direction in close contact with the heat generating portion of the electronic device and the other end portion in close contact with the heat radiating portion. The heat generating unit is, for example, a CPU of an electronic device. In addition, fins are usually used for the heat dissipation part, and there are many methods in which the fins are air-cooled by a fan.

Note that in a general heat pipe, in the heat generating part of an electronic device, the working liquid evaporates at one end to become steam, and this steam passes through the steam channel 66 in the heat pipe 61 to the other end. Moving. The other end is in close contact with the heat radiating portion, and the vapor is cooled and condensed to return to the liquid (working fluid). This working fluid flows back to one end again through the capillary channel 67 in the heat pipe 61. By repeating the movement of the working fluid by evaporation and condensation and capillary action, the heat generated in the heat generating part of the electronic device can be radiated very efficiently.
JP 2001-165854 A

  The conventional heat pipe shown as the above example is formed into a sheet using a film material as a container. For this reason, it is thin, lightweight and flexible, and can be used for a movable part. For example, the heat generated by the CPU of the notebook personal computer can be transferred to the heat radiating portion provided on the display side via the hinge portion to be radiated or the like.

  On the other hand, for example, a semiconductor laser used in an optical pickup which is a recording unit of a disk recording apparatus has an increased amount of heat generation due to higher output, and is required to dissipate heat efficiently. The following points are required for cooling such an apparatus. That is, the optical pickup to which the semiconductor laser is attached needs to be moved to a predetermined track position on the disk. Therefore, sufficient flexibility is required for the heat pipe for cooling. Furthermore, it is also required that the heat pipe performance is not deteriorated due to fluctuations in the pressure in the container even if the bending is repeated.

  On the other hand, the heat pipe is formed by laminating two films such as metal foils with a sealant layer. Therefore, when repeatedly bent, the sealing performance of the sealant layer deteriorates and air or the like A phenomenon that gas flows into the container is likely to occur. That is, this heat pipe has a configuration in which both end portions in the width direction are sealed by the sealant layer over the entire longitudinal direction, and a seal portion is also provided in a region that receives bending. Therefore, the seal performance of the seal portion is likely to deteriorate due to frequent bending. As a result, a predetermined pressure cannot be maintained inside the container, and there is a problem that it is difficult to ensure reliability by greatly degrading the performance of the heat pipe.

  The present invention was made in order to solve the problems of the conventional heat pipe, has flexibility, and is less likely to cause fluctuations in pressure inside the container even when subjected to relatively frequent bending. An object of the present invention is to provide a flexible heat pipe excellent in reliability and a manufacturing method thereof.

  In order to solve the above-described problems, a flexible heat pipe according to the present invention includes a working fluid, a flow passage body having a vapor flow path and a capillary flow passage for the working liquid, and a container enclosing the working liquid and the flow path body. The container has a first metal tube having a hollow shape in which one end portion is closed and a thickness that is thinner than the first metal tube and a second thickness that is thicker than the first metal tube. The middle part of the container is composed of a first metal pipe and a resin film formed on the outer surface of the first metal pipe.

  By adopting such a configuration, the middle part of the container has a thin and flexible first metal tube and a resin film laminated structure, and the evaporation part and the condensation part at both ends are thick. Since it can be comprised by the 2nd metal pipe which has rigidity, it can be easily attached to a heat generating object, a radiation fin, etc., and the heat pipe excellent in flexibility can be obtained. Furthermore, since there are no seals at both ends in the width direction of the container, the container can be kept airtight even when it is repeatedly bent. As a result, a flexible heat pipe with excellent reliability can be realized even when it is repeatedly bent.

  Moreover, in the said structure, the resin film may be formed also in the laminated metal pipe | tube of the intermediate part side of a container. By setting it as this structure, the intensity | strength of the boundary part of a laminated metal tube and a 1st metal tube can be enlarged. As a result, even if this region is subjected to stress during bending, the first metal tube can be prevented from cracking or breaking.

  In the above configuration, the first metal tube and the second metal tube may be made of a combination of materials that etch the second metal tube and do not etch the first metal tube. By adopting this configuration, it is possible to easily perform etching for making the middle portion of the container only the first metal tube.

  Moreover, in the said structure, you may provide a resin film further on the internal surface of the 1st metal tube of the intermediate part of a container. With this configuration, the bending resistance of the intermediate portion can be further improved.

  Further, the flexible heat pipe of the present invention includes a working fluid, a flow passage body having a vapor passage and a capillary passage for the working fluid, and a container enclosing the working fluid and the passage body, A first metal tube having a hollow shape in which one end is closed in a predetermined region at both ends and having a thin thickness and flexibility, and a thicker and more rigid first metal tube than the first metal tube. Two metal pipes are laminated and joined at least partially, and an intermediate portion of the container includes a first metal pipe and a resin film formed on the outer surface of the first metal pipe. Consists of configuration.

  By adopting such a configuration, the middle part of the container has a laminated structure of a first metal tube having flexibility and a resin film, and the evaporation part and the condensation part at both end parts are at least rigid. Therefore, it is possible to obtain a heat pipe that can be easily attached to a heat generating object, a heat radiating fin, or the like and has excellent flexibility. In addition, since there are no seal portions at both ends in the width direction of the container, even if bending is repeated, gas such as air does not flow into the container. As a result, a flexible heat pipe with excellent reliability can be realized even when used in a state where it is repeatedly bent.

  Moreover, in the said structure, the resin film may be formed also in the area | region which covers the junction part of a 1st metal tube and a 2nd metal tube. By adopting this configuration, even if stress acts on the first metal tube at the joint between the first metal tube and the second metal tube, it is possible to prevent the first metal tube from cracking or breaking. .

  Moreover, in the said structure, you may provide a resin film further on the internal surface of the 1st metal tube of the intermediate part of a container. With this configuration, the bending resistance of the intermediate portion can be further improved.

  Moreover, in the said structure, the cross-sectional shape of the width direction of a container may be a flat structure. By adopting such a configuration, close contact with a heat generating object, a heat radiating fin, or the like can be ensured, and better flexibility can be obtained.

  Also, the manufacturing method of the flexible heat pipe of the present invention is a laminated metal tube comprising a first metal tube having a small thickness and flexibility, and a second metal tube having a thickness larger than that of the first metal tube and having rigidity. The step of applying a resist film that is not attacked by a chemical solution for etching to a predetermined length region at both ends of the metal layer and the second metal tube in a region where the resist film of the laminated metal tube is not applied are selectively etched. A step of removing, a step of forming a resin film on the outer surface of the first metal tube excluding the evaporating part and the condensing part, a working liquid, a vapor flow path and a capillary flow path of the working liquid inside the laminated metal pipe The method includes a step of enclosing the flow path body having a step, and a step of sealing both ends in the longitudinal direction of the laminated metal tube and setting the reduced pressure state.

  By such a method, the evaporating part and the condensing part are composed of a rigid second metal tube, and the intermediate part is a simple flexible heat pipe composed of a flexible first metal tube and a resin film. It can be manufactured by a manufacturing process.

  In the flexible heat pipe manufacturing method of the present invention, a thick and rigid second metal tube is joined to a predetermined length region at both ends of the thin and flexible first metal tube. A step of forming a resin film on the outer surface of the first metal tube excluding the evaporating part and the condensing part, and a working liquid and a vapor flow path and a capillary flow path for the working liquid inside the laminated metal pipe The method includes a step of enclosing the flow channel body and a step of sealing both ends in the longitudinal direction of the laminated metal tube and setting the reduced pressure state.

  In the above method, the first metal tube and the second metal tube may be joined by any one of adhesive bonding, solder bonding, thermocompression bonding, or ultrasonic bonding.

  By such a method, the evaporating part and the condensing part are composed of a rigid second metal tube, and the intermediate part is a simple flexible heat pipe composed of a flexible first metal tube and a resin film. It can be manufactured by a manufacturing process. Furthermore, in the case of the present invention, since the second metal tube can be bonded by bonding, soldering, thermocompression bonding, ultrasonic bonding, or the like instead of processing such as etching, the manufacturing equipment cost is reduced. be able to.

  According to the present invention, since the seal portions are not provided at both ends in the width direction of the container, the airtightness can be maintained even if the container is repeatedly bent. In addition, since the second metal tube having rigidity is arranged in the evaporating part and the condensing part, it can be easily attached to a heat generating object, a heat radiating fin or the like. Furthermore, since the second metal tube is in direct contact with the heat generating object, the heat radiating fin, etc., heat can be transferred more efficiently. As a result, there is a great effect that a flexible heat pipe having excellent flexibility and good heat pipe performance can be obtained.

  Hereinafter, embodiments of the present invention will be described with reference to the drawings. In addition, about the same element, the same code | symbol is attached | subjected and description may be abbreviate | omitted.

(First embodiment)
1A and 1B are diagrams showing a configuration of a flexible heat pipe 10 according to a first embodiment of the present invention. FIG. 1A is a cross-sectional view taken along a longitudinal center line, and FIG. It is sectional drawing of the width direction in a line part.

  The flexible heat pipe 10 of the present embodiment encloses a working fluid (not shown), a flow passage body 11 having a vapor passage 12 and a capillary passage 13 for the working fluid, and the working fluid and the flow passage body 11. And a container 16 to be used. Then, the container 16 has a predetermined area at both ends thereof, a hollow shape in which one end is closed, a thin thickness, and a flexible first metal tube 19 and a first metal tube 19. It consists of a laminated metal tube 17 with a thick and rigid second metal tube 20, and an intermediate portion 18 of the container 16 is formed on the first metal tube 19 and the outer surface of the first metal tube 19. The resin film 21 is provided.

  In addition, in the portion of the flow path body 11 located in the intermediate portion 18 of the container 16, struts 14 for holding the vapor flow path 12 are arranged at regular intervals even in a bent or decompressed state.

  Hereinafter, the configuration will be described in more detail with reference to FIG. The flexible heat pipe 10 of the present embodiment includes a laminated metal tube 17 in which a first metal tube 19 having a small thickness and flexibility is clad on the inner surface side of a second metal tube 20 having a large thickness and rigidity. And using the container 16 having a configuration in which the second metal tube 20 of the intermediate portion 18 is removed by etching and the resin film 21 is formed on the outer surface of the first metal tube 19 exposed by this etching. It is.

  The thickness of the first metal tube 19 is preferably in the range of about 10 μm to 100 μm, for example, and the thickness of the second metal tube 20 is preferably in the range of about 0.2 mm to 1 mm, for example. Then, in the intermediate portion 18 of the container 16, the second metal tube 20 is removed by etching, and a resin film 21 made of, for example, polyimide resin is formed on the exposed outer surface of the first metal tube 19. . In the flexible heat pipe 10 of the present embodiment, the resin film 21 is also formed on the laminated metal tube 17 on the intermediate portion 18 side of the container 16. As the resin film 21, a film-like resin may be bonded with an adhesive or the like. Thus, since the intermediate part 18 of the container 16 is comprised by the 1st metal pipe 19 and the resin film 21 which have flexibility, airtightness is hold | maintained by the 1st metal pipe 19, and the resin film 21 Thus, repeated bending resistance can be maintained.

  A sealing portion 24 is provided at one end of the laminated metal tube 17 and hermetically sealed at the end. The sealing portion 24 is formed by thermocompression bonding or the like after the flow path body 11 and the working fluid are sealed in the container 16 and brought into a predetermined reduced pressure state.

  If the first metal tube 19 is made of copper, for example, and the second metal tube 20 is made of aluminum, only the aluminum can be selectively etched when the second metal tube is removed by etching.

  Moreover, ethanol, water, chlorofluorocarbon, etc. with a low saturated vapor pressure can be used as the working fluid. Furthermore, as the capillary flow path 13 of the flow path body 11, a metal fiber, a nonwoven fabric, etc. can be used. Moreover, the support | pillar 14 will not be restrict | limited especially if it is a comparatively big material, It is desirable to fix to the predetermined position of the flow-path body 11 previously. In addition, since this support | pillar 14 is arrange | positioned in the steam flow path 12, it is requested | required to arrange | position so that the flow of a steam may not be prevented.

  The flexible heat pipe 10 according to the present embodiment has the above-described configuration, and the regions of the laminated metal pipes 17 provided at both ends are an evaporation unit and a condensation unit. The evaporating unit is fixed in close contact with, for example, a semiconductor laser, and the condensing unit is fixed in close contact with the heat radiating fins or the casing. The intermediate portion 18 of the container 16 can move flexibly with the movement of the semiconductor laser. Moreover, in the intermediate portion 18, the first metal tube 19 mainly acts on hermetic sealing, and the resin film 21 acts to suppress the occurrence of cracks and the like on the first metal tube 19 against bending and the like. As a result, even if the heat generating object is movable, it has repeated bending resistance and can efficiently dissipate the heat generated by transmitting it to the heat radiating fins or the housing disposed in the fixed portion. .

  Further, even if there is a difference in height between the heat generating object and the heat radiating fin or the housing or the case where the heat generating object cannot be arranged in the same direction, the flexible heat pipe 10 of the present embodiment can be used as the container 16. Since the intermediate portion 18 can be freely bent and disposed, the intermediate portion 18 can also be used for a heating object of an electronic device that is small and mounted with high density.

  FIG. 2 is a cross-sectional view of main processes for explaining the method for manufacturing the flexible heat pipe 10 according to the present embodiment. In addition, although FIG. 2 shows a cross-sectional view along the center line in the longitudinal direction of the flexible heat pipe 10, the intermediate portion is shown in a reduced scale.

  As shown in FIG. 2A, a laminated metal in which a first metal tube 19 made of copper and having a thickness of about 35 μm and a second metal tube 20 made of aluminum and having a thickness of about 350 μm are clad. A tube 17 is prepared. Such a laminated metal tube 17 can be manufactured by forming copper on the inner surface of the second metal tube 20 made of, for example, aluminum by a plating method. The cross-sectional shape in the width direction of the laminated metal tube 17 is a flat shape as shown in FIG. Alternatively, the above-described thickness can be obtained by drawing a pipe clad with copper and aluminum by drawing.

  Next, as shown in FIG. 2B, the reinforcing plate 26 is inserted into the laminated metal tube 17. The reinforcing plate 26 has substantially the same shape as the inner surface of the laminated metal tube 17 and is intended to prevent the intermediate portion 18 from being easily bent when the second metal tube 20 is removed by etching. Further, as shown in the drawing, a resist film 28 that is not attacked by the liquid for etching the second metal tube 20 is formed in the region to be left as the state of the laminated metal tube 17. In the case of the present embodiment, since the second metal tube 20 is aluminum, it can be etched by a mixed solution of phosphoric acid, nitric acid and acetic acid. For this solution, a commonly used photoresist can be used as the resist film 28.

  Next, as shown in FIG. 2C, the second metal tube 20 in the intermediate region is removed by etching. In this case, only the aluminum can be etched by immersing the laminated metal tube 17 in the mixed solution of phosphoric acid, nitric acid and acetic acid. Then, after confirming that the copper surface of the first metal tube 19 is exposed, the etching is finished. Thereafter, the resist film 28 is removed.

  Next, as shown in FIG. 2D, a resin film 21 is formed on the exposed first metal tube 19 and a part of the second metal tube 20 in the vicinity thereof. The resin film 21 can be formed, for example, by applying liquid polyimide and drying. Or you may adhere | attach a film-form resin sheet with an adhesive agent. The intermediate portion 18 of the container 16 is formed by the first metal tube 19 and the resin film 21. And the basic structure of the container 16 is obtained by forming the intermediate part 18.

  Next, as shown in FIG. 2 (e), the reinforcing plate 26 is pulled out and the flow path body 11 is inserted. The channel body 11 has substantially the same shape as the inner surface shape of the laminated metal tube 17, and a capillary channel 13 is provided on the surface side in contact with the first metal tube 19, and a region surrounded by the capillary channel 13 is a vapor. This is the flow path 12. The struts 14 are arranged in the steam channel 12 at a constant pitch. As described above, the capillary channel 13 can be made of, for example, metal fiber or non-woven fabric, and has flexibility. Further, the support posts 14 are arranged at a predetermined pitch at predetermined positions of the flow path body 11. Therefore, the flow path body 11 also has flexibility and can be easily inserted into the container 16.

  Thereafter, one end of the laminated metal tube 17 is subjected to, for example, thermocompression bonding to form a sealing portion 24. In this state, the inside of the container 16 is sufficiently evacuated to remove the gas adsorbed inside. Thereafter, the working fluid is injected, and the other end of the laminated metal tube 17 is similarly subjected to, for example, thermocompression bonding to form the sealing portion 24. Thereby, the flexible heat pipe 10 of this Embodiment shown in FIG. 1 is produced.

  In the present embodiment, the first metal tube 19 is clad on the inner surface side of the second metal tube 20, but may be clad on the outer surface side of the second metal tube 20. . In this case, the first metal tube 19 can be formed not only by a plating method but also by a physical film forming method such as a vapor deposition method or a sputtering method or a thermal spraying method.

  In the present embodiment, the resin film 21 is formed on the outer surface of the first metal tube 19 of the intermediate portion 18 of the container 16, but a resin film may also be formed on the inner surface. By doing in this way, the bending tolerance of an intermediate part can be improved further. As a method for forming a resin film on the inner surface, a protective film or a protective sheet is provided in advance on the evaporation section and the condensation section, and then immersed in a resin liquid to be a resin film.

(Second Embodiment)
3A and 3B are diagrams showing the configuration of the flexible heat pipe 30 according to the second embodiment of the present invention, in which FIG. 3A is a cross-sectional view taken along the center line in the longitudinal direction, and FIG. It is sectional drawing of the width direction in a line part.

  The flexible heat pipe 30 of the present embodiment encloses a working fluid (not shown), a flow passage body 31 having a vapor passage 32 and a capillary passage 33 for the working fluid, and the working fluid and the flow passage body 31. Container 35. The container 35 has a first metal tube 38 having a hollow shape with one end closed in a predetermined region at both ends thereof, a thin thickness and a flexibility, and the first metal tube 38. The second metal tube 36 having a larger thickness and rigidity is laminated and joined at least partially. Further, the intermediate portion 37 of the container 35 is configured to include a first metal tube 38 and a resin film 39 formed on the outer surface of the first metal tube 38.

  Furthermore, the flexible heat pipe 30 of the present embodiment is also formed in a region where the resin film 39 covers the joint portion 41 between the first metal tube 38 and the second metal tube 36. The cross-sectional shape of the container 35 in the width direction is a flat structure.

  In addition, in the portion of the flow path body 31 located in the intermediate portion 37 of the container 35, struts 34 for holding the vapor flow path 32 are arranged at regular intervals even in a bent or decompressed state. One end portion of the second metal tube 36 is hermetically sealed by the sealing portion 40.

  Hereinafter, the configuration will be described in more detail with reference to FIG. In the flexible heat pipe 30 of the present embodiment, the first metal tube 38 having a small thickness and flexibility is joined to a part of the outer surface of the second metal tube 36 having a large thickness and rigidity. By the joint portion 41, the first metal tube 38 and the second metal tube 36 are joined in an airtight state. In addition, you may join so that most outer surfaces of the 2nd metal pipe 36 may be covered.

  Further, a resin film 39 is formed on the outer surface of the first metal tube 38 including the joint portion 41. The resin film 39 can be formed by using the same material and manufacturing method as those in the first embodiment, and thus description thereof is omitted. The thickness of the first metal tube 38 is preferably in the range of about 10 μm to 100 μm, for example, and the thickness of the second metal tube 36 is preferably in the range of about 0.2 mm to 1 mm, for example.

  A sealing portion 40 is provided at one end portion of the second metal tube 36, and hermetic sealing is performed at the end portion. The sealing portion 40 is formed by thermocompression bonding or the like after the flow path body 31 and the working fluid are sealed in the container 35 and brought into a predetermined reduced pressure state.

  For example, copper can be used for both the first metal tube 38 and the second metal tube 36. Then, if a gold film is formed on one side and a tin film is formed on the other side in the region that becomes the joint portion 41 of the first metal pipe 38 and the second metal pipe 36, hermetic sealing is easily performed by thermocompression bonding. be able to. Alternatively, if a gold film is formed on both surfaces, hermetic sealing can be performed by ultrasonic bonding. Or you may join by soldering. Furthermore, you may join by an adhesive agent.

  Moreover, ethanol, water, chlorofluorocarbon, etc. with a low saturated vapor pressure can be used as the working fluid. Furthermore, as the capillary flow path 33 of the flow path body 31, a metal fiber, a nonwoven fabric, etc. can be used. Moreover, the support | pillar 34 will not be restrict | limited especially if it is a material with comparatively big rigidity, It is desirable to fix to the predetermined position of the flow-path body 31 previously. In addition, since this support | pillar 34 is arrange | positioned in the steam flow path 32, it is requested | required to arrange | position so that a flow of steam may not be prevented.

  The flexible heat pipe 30 of the present embodiment has the above-described configuration, and the regions of the second metal pipes 36 provided at both ends serve as an evaporation unit and a condensation unit. For example, the evaporation unit is fixed in close contact with the semiconductor laser, and the condensing unit is fixed in close contact with the heat radiation fin. The intermediate portion 37 of the container 35 can move flexibly with the movement of the semiconductor laser. Thereby, even if the heat generating object is movable, the heat generated from the heat generating object can be efficiently transmitted to the heat dissipating fins arranged in the fixed portion to be dissipated.

  Even if there is a difference in height between the heat generating object and the heat radiating fins, or when the heat dissipating object and the heat dissipating fins cannot be arranged in the same direction, the intermediate portion 37 of the container 35 can be used in the flexible heat pipe 30 of the present embodiment. Can be freely bent and placed, so that it can also be used for a heat generating object of an electronic device that is small and mounted with high density.

  FIG. 4 is a cross-sectional view of main processes for explaining the method for manufacturing the flexible heat pipe 30 according to the present embodiment. 4 shows a cross-sectional view along the center line in the longitudinal direction of the flexible heat pipe 30, the intermediate portion is shown in a reduced scale.

  As shown in FIG. 4A, a first metal tube 38 made of, for example, copper and having a thickness of about 35 μm is prepared.

  Next, as shown in FIG. 4B, a part of the second metal tube 36 is inserted into both ends of the first metal tube 38. In this case, if the inner diameter of the first metal tube 38 is slightly smaller than the outer diameter of the second metal tube 36 and the first metal tube 38 is heated to increase the spreadability, the first metal tube 38 is brought into close contact. Cheap. In this state, thermocompression bonding or ultrasonic bonding is performed, and the sealing portion 41 is hermetically sealed. It is also possible to perform hermetic sealing by fixing by soldering or adhesive. In this case, the inner diameter of the first metal tube 38 may be larger than the outer diameter of the second metal tube 36.

  Next, as shown in FIG. 4C, a resin film 39 is formed so as to cover the exposed first metal tube 38 and the joint portion 41. Since the resin film 39 can be formed using the material and the manufacturing method described in the first embodiment, description thereof is omitted. By forming the resin film 39, the basic configuration of the container 35 can be obtained.

  Next, as shown in FIG. 4D, the flow path body 31 is inserted. In the channel body 31, the steam channel 32 is slightly narrowed in the inner surface region of the second metal tube 36, and the steam channel 32 is widened by the thickness of the second metal tube 36 in the intermediate portion 37. If the capillary channel 33 and the support column 34 are made of an elastic material, even if the capillary channel 33 and the column 34 are inserted through the inner diameter portion of the second metal tube 36, the first metal tube is formed at the intermediate portion 37 of the container 35. It can be made to contact the inner surface of 38.

  Thereafter, one end of the second metal tube 36 is subjected to, for example, thermocompression bonding to form the sealing portion 40. In this state, the inside of the container 35 is sufficiently evacuated to remove the gas adsorbed inside. Thereafter, the working fluid is injected, and the end of the other end of the second metal tube 36 is similarly thermocompression-bonded to form the sealing portion 40. Thereby, the flexible heat pipe 30 of this Embodiment shown in FIG. 3 is produced.

  As described above, in the manufacturing method of the present embodiment, the end portion of the first metal tube 38 that is thin and flexible is joined to the end portion of the second metal tube 36 that is thicker and more rigid. A joining portion 41 is formed, and a resin film 39 is further formed on the first metal tube 38 and the joining portion 41. As a result, a flexible heat pipe having flexibility and being easy to be in close contact with the heat generating object and the heat radiating fins and having good heat conduction can be manufactured by a simple manufacturing process.

  In the present embodiment, the resin film 39 is formed on the outer surface of the first metal tube 38 of the intermediate portion 37 of the container 35. However, a resin film may be formed on the inner surface. By doing in this way, the bending tolerance of an intermediate part can be improved further. As a method for forming a resin film on the inner surface, a protective film or a protective sheet is provided in advance on the evaporation section and the condensation section, and then immersed in a resin liquid to be a resin film.

  The flexible heat pipe of the present invention comprises a metal tube having rigidity and good heat conductivity at the evaporation part and the condensation part at both ends, and a thin and flexible metal tube and a resin film at the middle part. Therefore, it is possible to prevent deterioration of the cooling performance due to leakage or the like even under use conditions in which bending is performed relatively frequently. Therefore, in an electronic device or the like, a movable heating object or the like can be efficiently cooled, which is useful in various electronic device fields.

It is a figure which shows the structure of the flexible heat pipe concerning the 1st Embodiment of this invention, (a) is sectional drawing cut | disconnected along the centerline of a longitudinal direction, (b) is the width direction in an AA line part. Cross section of Sectional drawing of the main process for demonstrating the manufacturing method of the flexible heat pipe concerning the embodiment It is a figure which shows the structure of the flexible heat pipe concerning the 2nd Embodiment of this invention, (a) is sectional drawing cut | disconnected along the centerline of a longitudinal direction, (b) is the width direction in a BB line part. Cross section of Sectional drawing of the main process for demonstrating the manufacturing method of the flexible heat pipe concerning the embodiment Sectional view in the width direction of a conventional heat pipe

Explanation of symbols

DESCRIPTION OF SYMBOLS 10,30 Flexible heat pipe 11,31 Flow path body 12,32 Steam flow path 13,33 Capillary flow path 14,34 Post column 16,35 Container 17 Laminated metal pipe 18,37 Middle part 19,38 1st metal pipe 20 , 36 Second metal tube 21, 39 Resin film 24, 40 Sealing portion 26 Reinforcing plate 28 Resist film 41 Joint portion

Claims (11)

Hydraulic fluid,
A flow path body having a vapor flow path and a capillary flow path for the hydraulic fluid;
A container enclosing the hydraulic fluid and the flow path body;
The container has a first metal tube having a hollow shape in which one end is closed in a predetermined region at both ends thereof, and a second metal having a thickness greater than that of the first metal tube. It consists of a laminated metal tube with a tube,
The flexible heat pipe according to claim 1, wherein an intermediate portion of the container includes a first metal tube and a resin film formed on an outer surface of the first metal tube. 3. The flexible heat pipe according to claim 1, wherein the resin film is also formed on the laminated metal tube on an intermediate portion side of the container. 2. The first metal tube and the second metal tube are made of a combination of materials that etch the second metal tube and do not etch the first metal tube. Or the flexible heat pipe of Claim 2. The flexible heat pipe according to any one of claims 1 to 3, wherein a resin film is further provided on an inner surface of the first metal tube in an intermediate portion of the container. Hydraulic fluid,
A flow path body having a vapor flow path and a capillary flow path for the hydraulic fluid;
A container enclosing the hydraulic fluid and the flow path body;
The container has a hollow shape in which one end is closed in a predetermined region at both ends of the container, and the first metal tube having a small thickness and flexibility is thicker than the first metal tube. A rigid second metal tube is laminated and bonded at least partially;
The flexible heat pipe according to claim 1, wherein an intermediate portion of the container includes a first metal tube and a resin film formed on an outer surface of the first metal tube. The flexible heat pipe according to claim 5, wherein the resin film is also formed in a region that covers a joint portion between the first metal tube and the second metal tube. The flexible heat pipe according to claim 5 or 6, wherein a resin film is further provided on an inner surface of the first metal tube at an intermediate portion of the container. The flexible heat pipe according to any one of claims 1 to 7, wherein a cross-sectional shape of the container in the width direction is a flat structure. Etching is performed in a predetermined length region at both end portions of a laminated metal tube composed of a first metal tube having a small thickness and flexibility and a second metal tube having a thickness larger than that of the first metal tube and having rigidity. Applying a resist film that is not affected by chemicals for use;
Selectively etching away the second metal tube in a region where the resist film of the laminated metal tube is not applied;
Forming a resin film on the outer surface of the first metal tube excluding the evaporation section and the condensation section;
Enclosing a working liquid and a flow path body having a vapor flow path and a capillary flow path of the working liquid inside the laminated metal tube;
A method of manufacturing a flexible heat pipe, comprising: sealing both ends of the laminated metal tube in the longitudinal direction and setting a reduced pressure state. Joining a second metal tube having a large thickness and rigidity to a predetermined length region at both ends of the first metal tube having a small thickness and flexibility;
Forming a resin film on the outer surface of the first metal tube excluding the evaporation section and the condensation section;
Enclosing a working liquid and a flow path body having a vapor flow path and a capillary flow path of the working liquid inside the laminated metal tube;
A method of manufacturing a flexible heat pipe, comprising: sealing both ends of the laminated metal tube in the longitudinal direction and setting a reduced pressure state. 11. The bonding between the first metal tube and the second metal tube is any one of bonding by an adhesive, bonding by soldering, bonding by thermocompression bonding, or bonding by ultrasonic waves. The manufacturing method of the flexible heat pipe of description.

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