JP2002235990A - Method for fixing heat pipe to thermal transmittance member - Google Patents

Abstract

PROBLEM TO BE SOLVED: To fix a heat pipe rigidly to a thermal transmittance member without producing any deformation (strain) in it. SOLUTION: A heat pipe 5 having working liquid sealingly enclosed therein is inserted into and passed through a heat pipe insertion hole 1 of the thermal transmittance member 4 with a part of the heat pipe 5 being exposed. When the heat pipe 5 is thermoplastically deformed in its diametrically expanding direction, an exposed portion 6 of the heat pipe 5 is arranged at a heat pipe fixing hole 8 of a fixing jig 7, and the heat pipe 5 is heated to cause a thermoplastic deformation to be attained in a diametrically expanding direction. Since the exposed portion 6 of the heat pipe is fixed at the heat pipe fixing hole 8, the exposed portion 6 of the heat pipe is prevented from being deformed (strained). When the heat pipe fixing hole 8 is machined in a high precision, a size accuracy of the exposed portion 6 of the heat pipe is improved. Since the expanded diameter of the exposed portion 6 is restricted by the fixing hole 8, the heat pipe 5 is well expanded in its diameter within the heat pipe insertion hole 1, and an anti-pulling characteristic of the heat pipe 5 from within the insertion hole 1 is improved.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an improvement in a method for attaching a heat pipe to a heat transfer member.

[0002]

2. Description of the Related Art In many cases, a metal substrate or a heat transfer member having a radiating fin mounted on the metal substrate is used by burying a heat pipe in the metal substrate in order to improve heat dissipation. The method of embedding the heat pipe in a heat transfer member,
There are a method of shrinking the heat pipe into the heat pipe insertion hole of the heat transfer member, and a method of soldering the heat pipe to the heat pipe insertion hole of the heat transfer member. However, the former requires a high degree of dimensional accuracy, and the latter requires plating on both contact surfaces in order to improve solder wettability, and requires time and effort in soldering, and both methods are costly. There was a problem of becoming.

For this reason, as shown in FIG. 10, a heat pipe 5 is inserted into the heat pipe insertion hole 1 of the heat transfer member 4 in which the radiation fins 3 are brazed to the surface of the aluminum substrate 2 having the heat pipe insertion hole 1. The heat pipe 5 is inserted into the heating furnace 13 by heating while exposing a part to be an evaporating part or a condensing part, and is heated in the heating furnace 13. A method of deforming and embedding the heat pipe 5 in the insertion hole 1 has been proposed (Patent Document 2).
793978).

[0004]

However, this method is
The exposed portion 6 of the heat pipe may be unevenly deformed (warped) during heating or burst, resulting in a low production yield, and the heat pipe 5 may fall out of the insertion hole 1 during use. . The present invention has been made in view of such a situation, and an object of the present invention is to provide a method for firmly attaching a heat pipe to a heat transfer member without causing deformation (distortion) or the like.

[0005]

According to the first aspect of the present invention,
A part of the heat pipe is exposed and inserted into a heat pipe insertion hole of a heat transfer member through which a heat pipe filled with a working fluid is inserted, and the heat pipe is plastically deformed in a radially expanding direction, thereby forming the heat pipe. In the method of attaching a heat pipe to the heat transfer member embedded in the heat pipe insertion hole of the heat transfer member, the exposed portion of the heat pipe is arranged in a heat pipe fixing hole of a fixing jig, and then the heat pipe is heated. This is a method of attaching a heat pipe to a heat transfer member, wherein the heat pipe is plastically deformed in a diameter increasing direction.

The invention according to claim 2 is characterized in that the heat pipe is heated by a heating element provided in the fixing jig and is plastically deformed in a radially expanding direction. This is the method of mounting the heat pipe.

According to a third aspect of the present invention, at least a part of the inner surface of the heat pipe insertion hole of the heat transfer member has a surface roughness Ra.
3. The surface of the heat pipe is roughened so as to have a thickness of 0.1 to 40 μm to increase the frictional resistance between the heat pipe and the inner surface of the insertion hole, thereby making it difficult for the heat pipe to fall out of the insertion hole. This is a method of attaching a heat pipe to the heat transfer member.

According to a fourth aspect of the present invention, a concave portion is provided on an inner surface of the heat pipe insertion hole of the heat transfer member, and a surface layer of the heat pipe is expanded in the concave portion, or an inner surface of the heat pipe insertion hole of the heat transfer member. 3. The heat transfer member according to claim 1, wherein a convex portion is provided on the heat transfer member, and a surface layer of the heat pipe is swelled at a portion other than the convex portion, so that the heat pipe is hardly removed from the insertion hole. This is the method of mounting the heat pipe.

According to a fifth aspect of the present invention, a heat pipe in which a working fluid is sealed is inserted through a heat pipe insertion hole of a heat transfer member by exposing a part of the heat pipe, thereby expanding the diameter of the heat pipe. In a method of attaching a heat pipe to a heat transfer member for plastically deforming the heat pipe in a direction and burying the heat pipe in a heat pipe insertion hole of the heat transfer member, a plurality of radiating fins having holes formed in the exposed portion of the heat pipe are provided. And then heating the heat pipe to plastically deform it in the diameter-enlargement direction.

According to a sixth aspect of the present invention, the sectional shape of the heat pipe insertion hole of the heat transfer member and the portion embedded in the heat pipe insertion hole is elliptical. It is a method of attaching a heat pipe to the heat transfer member according to any one of 4, 4, and 5.

[0011]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS The present invention will be specifically described below with reference to the drawings. An aluminum substrate 2 having a heat pipe insertion hole 1 as shown in FIG.
The heat pipe 5 is inserted through the heat pipe insertion hole 1 of the heat transfer member 4 to which the radiation fin 3 is brazed on the surface of the heat transfer member 4 while exposing a portion to be an evaporating portion or a condensing portion, and then FIG. The exposed portion 6 of the heat pipe 1 is arranged in a heat pipe fixing hole 8 of a fixing jig 7 as shown in FIG. 1, and the whole is put into a heating furnace (not shown) and heated to heat the heat pipe 5. In this method, the heat pipe 5 is buried in the heat transfer member 4 by being plastically deformed in the radially expanding direction by the vapor pressure of the working fluid.

In this method, since the exposed portion 6 of the heat pipe 1 is fixed to the fixing hole 8 of the fixing jig 7 and heated, the exposed portion 6 may be deformed (warped) or burst during heating. Absent. Further, by processing the inner surface of the fixing hole 8 with high precision, it is possible to improve the dimensional accuracy of the exposed portion 6 of the heat pipe, such as the outer diameter, roundness, straightness, and arrangement pitch. Further, since the diameter of the exposed portion 6 is suppressed by the fixing hole 8, the diameter of the heat pipe 5 in the heat pipe insertion hole 1 of the heat transfer member 4 is favorably increased. Has improved anti-pulling resistance.
In all the drawings describing the embodiments, components having the same function are denoted by the same reference numerals, and repeated description thereof will be omitted.

According to a second aspect of the present invention, in the first aspect of the invention, the fixing jig is provided with a heating element (not shown), and only the exposed portion 6 of the heat pipe 5 is formed by the heating element. This is a method of attaching a heat pipe to a heat transfer member to be heated. In the present invention, only the exposed portion of the heat pipe 5 arranged in the fixing hole 8 of the fixing jig 7 is heated by the heating element provided in the fixing jig 7, so that the entire heat transfer member 4 including the heat hype 5 is heated. In comparison with the method, the heat pipe 5 can be heated and expanded in a short time, and the productivity is excellent. Equipment costs are also low. Further, the heating temperature can be controlled with high accuracy.

As the fixing jig 7, any fixing jig can be used, but a split mold (see FIG. 1) including an upper mold 14 and a lower mold 15 is preferable because of good workability. Although any heating element can be used as the heating element provided in the fixing jig 7, a resistance heating element is preferable because the temperature can be easily controlled.

According to a third aspect of the present invention, as shown in FIG. 2A, a roughened portion 16 is formed in which at least a part of the inner surface of the heat pipe insertion hole 1 of the heat transfer member 4 is roughened. ,
A heat pipe 5 is inserted through the insertion hole 1, the heat pipe 5 is heated, and the heat pipe is plastically deformed in a radially expanding direction as shown in FIG. 2 (b). Since the frictional resistance between the roughened portion 16 on the inner surface of the insertion hole 1 and the heat pipe 5 increases, the heat pipe 5 is harder to come out of the insertion hole 1.

In the present invention, the reason why the surface roughness Ra of the roughened portion 16 provided on at least a part of the inner surface of the insertion hole is defined to be 0.1 to 40 μm is that Ra is 0.1 μm.
If it is less than 40 μm, the effect cannot be obtained sufficiently, and if Ra exceeds 40 μm, the effect will be saturated, and additional work will be required for roughening. The longer the length of the roughened portion 16 on the inner surface of the insertion hole, the more difficult it is for the heat pipe to come off. However, if the length of the roughened portion 16 is about 2 mm, sufficient release resistance can be obtained. In addition, it is preferable that the length of the roughened portion 16 is shorter even in consideration of the labor for roughening.

In the present invention, the inner surface of the insertion hole is roughened to increase the frictional resistance with the heat pipe surface.
In the case where the intended pull-out resistance (pull-out resistance) is the same, the present invention can shorten the heating time as compared with the conventional method in which the inner surface of the insertion hole is not roughened. An arbitrary method such as an etching method and a mechanical processing method (for example, lathe processing and sanding) can be applied to the surface roughening. The roughening position is preferably near the entrance of the insertion hole for ease of processing.

As shown in FIG. 3, the invention according to claim 4 has open recesses 9 at both ends of the inner surface of the heat pipe insertion hole 1 of the heat transfer member 4 so that when the heat pipe 5 is heated and expanded in diameter, This is a mounting method in which the surface layer of the heat pipe 5 is swelled in the concave portion 9 and the heat pipe 5 is engaged with the insertion hole 1 of the heat transfer member 4 so that the heat pipe 5 is hard to come out of the insertion hole 1.

According to a fourth aspect of the present invention, as shown in FIG. 4, a closed recess 10 is provided at a required position on the inner surface of the heat pipe insertion hole 1 of the heat transfer member 4, and the surface of the heat pipe 5 is provided in the recess 10. And the heat pipe 5 is connected to the heat transfer member 4.
This is an attachment method in which the heat pipe 5 is hardly pulled out of the insertion hole 1 by being engaged with the insertion hole 1.

According to a fourth aspect of the present invention, as shown in FIG. 5, an open recess 9 is provided at one end of the heat pipe insertion hole 1 of the heat transfer member 4, and a fixing jig at the other end of the insertion hole 1 is provided. Tool 7
An open recess 11 is provided on the inner surface of the end of the fixing hole 8 on the heat transfer member 4 side, and the surface layer of the heat pipe 5 is swelled in the recesses 9 and 11, and the heat pipe 5 is inserted into the insertion hole 1 of the heat transfer member 4. This is a mounting method in which the heat pipe 5 is prevented from coming out of the insertion hole 1 by being engaged.

The recesses 9, 10, and 11 can be formed by any method such as cutting, pressing, and etching.
The location where the concave portion 10 is provided is arbitrary, but it is desirable that the vicinity of the entrance of the insertion hole 1 is easily processed.

According to a fourth aspect of the present invention, as shown in FIG. 6, a predetermined portion of the heat transfer member 4 is pressed by a press or the like to provide a convex portion 12 on the inner surface of the insertion hole 1 and the heat transfer member The heat pipe 5 is inserted into the heat pipe insertion hole 1 of the member 4,
The heat pipe 5 is heated and expanded to expand portions other than the protrusions 12, and the heat pipe 5 is engaged with the insertion hole 1 of the heat transfer member 4 so that the heat pipe 5 is hard to be pulled out of the insertion hole 1. This is the mounting method.

In addition, a concave portion may be provided on the inner surface of the fixing hole of the fixing jig, and the exposed portion of the heat pipe may be expanded in the concave portion, and the expanded portion may be used for positioning the heat transfer member. it can.

In the present invention, a heat transfer member is any heat conductive member having a heat pipe insertion hole such as a metal substrate having a heat pipe insertion hole, a member having a heat radiating fin provided on a metal substrate having a heat pipe insertion hole. Refers to members.

According to the present invention, by combining the inventions of the third and fourth aspects, the heat pipe can be buried more firmly in the insertion hole.

According to a fifth aspect of the present invention, as shown in FIG. 7, the exposed portion 6 of the heat pipe 5 is passed through a hole 24 formed in the radiation fin 23 so that the exposed portion 6 of the heat pipe 5 is expanded in the radial direction. Mounting of the heat pipe 5 to the heat transfer member 4 for suppressing the plastic deformation of the heat pipe 5 at the inner surface of the hole 24 formed in the heat radiation fin 23 and preventing the exposed portion 6 of the heat pipe 5 from being deformed (distorted) or ruptured upon heating. Is the way.

In the present invention, the hole diameter of the heat radiating fin 23 is made slightly larger than the outer diameter of the heat pipe 5, and the exposed portion 6 of the heat pipe 5 is inserted into the hole 24 formed in the heat radiating fin 23 before heating. It is preferable to make it easy to suppress the deformation (distortion) of the exposed portion of the heat pipe 5 at the time of heating.

In the present invention, in order to more reliably prevent the deformation (distortion) and rupture of the exposed portion of the heat pipe 5, the arrangement interval of the radiating fins 23 is narrowed and a thick radiating fin is used. As shown in the figure, a method of using the heat radiation fins 23 in which the holes 25 are burred, a method of disposing a metal pipe between the heat radiation fins 23, and the like are employed.

In this method, the exposed portion 6 of the heat pipe 5
Since the heat dissipating fins 23 are used to prevent deformation (distortion) or the like, the fixing jig is not required. Further, since the radiation fins 23 can be used as they are, there is no need to attach the radiation fins using a press-fitting machine in a later process, which is advantageous in terms of equipment and productivity. In this method, a separate heating means is required. However, the radiating fins 23 are usually made of a thin plate and have a small heat capacity, so that the heating can be performed quickly and the productivity is not hindered.

In the present invention, the shape of the heat pipe is arbitrary, but the cross section of the heat pipe insertion hole of the heat transfer member and the portion embedded in the insertion hole of the heat pipe is made elliptical so that the heat pipe has a circular cross section. When the outer peripheral length and the wall thickness of the heat pipe are the same as compared with the case, (1) the thickness of the heat transfer member can be reduced to save space, and (2) the heat pipe becomes plastic in the radially expanding direction. It becomes easy to deform, and the heating temperature when expanding the heat pipe can be lowered.

[0031]

The present invention will be described below in detail with reference to examples. (Example 1) As shown in FIG. 1, an aluminum plate (JISA1) having six heat pipe insertion holes having an inner diameter of 6.7 mm.
100, width 200 mm, thickness 10 mm)
This aluminum plate was cut into a length of 110 mm to form an aluminum substrate, and a corrugated fin having a height of 15 mm was brazed to the surface of the aluminum substrate to form a heat transfer member. Next, a heat pipe 5 having an outer diameter of 6.35 mm and a length of 220 mm is inserted into each of the insertion holes 6 to form an assembly. The exposed portion (length 110 mm) 6 of the heat pipe 5 of the assembly is removed. It is fixed to the fixing hole (inner diameter 6.50 mm) 8 of the two-part fixing jig 7, put into a heating furnace, heated at 300 ° C. for 20 minutes, and plastically deforms the heat pipe 5 in the radial direction to manufacture a heat sink. did.

COMPARATIVE EXAMPLE 1 As shown in FIG. 10, the assembly was placed in a heating furnace without using the fixing jig 7 and heated at 300.degree.
A heat sink was manufactured in the same manner as in Example 1, except that the heat pipe 5 was plastically deformed in the radial direction by heating for 0 minutes.

Each of the 20 obtained in Example 1 and Comparative Example 1
For each of the heat sinks, the appearance (existence of bending) and the dimensional accuracy (variation in outer diameter) of the exposed portion of the heat pipe were examined. As a result, each of the heat sinks of Example 1 (Example of the present invention) had a certain resistance to detachment, and was excellent in appearance and dimensional accuracy. That is, since the exposed part of the heat pipe was arranged and heated in the fixing hole (processed with high precision) of the fixing jig, there was no deformation (distortion) due to heat, and the appearance (straightness) was better than before heating. The outer diameter was increased to 6.50 mm in accordance with the shape of the fixing hole, but the dimensional accuracy of the exposed portion was extremely good because the inner diameter of the fixing hole was finished with high accuracy. On the other hand, the heat sinks of Comparative Example 1 (conventional method) had two inferior appearance, three inferior in dimensional accuracy, and one inferior in both appearance and dimensional accuracy, and the manufacturing yield was 70%. Has dropped.

Example 2 As shown in FIG. 1, an aluminum plate having six heat pipe insertion holes having an inner diameter of 6.7 mmφ (JISA1100, width 200 mm, thickness 10 mm)
Is extruded, and this aluminum plate is cut into a length of 110 mm to form an aluminum substrate.
Was brazed to form a heat transfer member.
Next, each of the insertion holes 6 has an outer diameter of 6.35 mm and a length of 2 mm.
The exposed part (length 110 mm) 6 of the heat pipe 5 is fixed to the fixing hole 8 of the two-part fixing jig 7 by inserting the 20 mm heat pipe 5, and the exposed part 6 is provided in the fixing jig 7. The heat pipe 5 was heated at 300 ° C. for 20 minutes by the resistance heating element, and the heat pipe 5 was plastically deformed in the radially expanding direction to produce a heat sink.

With respect to the 20 heat sinks obtained in Example 2, the appearance and dimensional accuracy of the exposed portions of the heat pipe were examined. All of them were good, and the pull-out resistance satisfied certain criteria. Since this method heats only the exposed portion of the heat pipe, it is more economical than the method using the heating furnace of Example 1, and the heating temperature can be easily controlled.
Further, the heating time could be shortened.

(Example 3) A heat sink is manufactured by the same method as in Example 1, except that the inner peripheral surface near the entrance of the heat pipe insertion hole of the heat transfer member is sanded and roughened to a length of 2 mm. did. The surface roughness (roughness in the length direction) Ra of the roughened portion was variously changed within the range of 0.1 to 40 μm.

(Comparative Example 2) Surface roughness (lengthwise roughness)
A heat sink was manufactured in the same manner as in Example 2 except that Ra was less than 0.1 μm or more than 40 μm.

With respect to each of the heat sinks manufactured in Example 2 and Comparative Example 2, the resistance of the heat pipe to the heat pipe through the aluminum substrate insertion hole was examined. The pull-out resistance was measured by fixing the aluminum substrate of the heat sink to one chuck of the tensile tester, performing a tensile test with one heat pipe sandwiched between the other chucks, and expressing the maximum load when the heat pipe comes off. Each of the three heat sinks was tested, and the average value is shown in Table 1. Table 1 also shows the surface roughness Ra. In addition, the roughness of the inner surface of the insertion hole (the roughness when the file is not filed) is usually about 0.08 to 0.1 μm.

[0039]

[Table 1]

As is clear from Table 1, N of the present invention example
o. All of Nos. 1 to 6 showed high pull-out resistance. This is because the surface roughness Ra of the inner surface of the insertion hole was appropriate, and sufficient frictional resistance occurred between the heat pipe and the inner surface of the insertion hole. On the other hand, in Comparative Example No. Sample No. 7 had a low surface roughness and thus had a low pull-out resistance. No. In No. 8, the effect of roughening the inner surface of the insertion hole is saturated.

Example 4 A heat sink was formed in the same manner as in Example 2 except that the open-type recess 9 shown in FIG. 3 was provided at both entrances of the insertion hole 1 on the inner surface of the heat pipe insertion hole of the heat transfer member. Was manufactured. The recess 9 had a length of 2 mm and a diameter of 6.9 mm. The anti-peeling power of this product was extremely high at 1330N.

It is needless to say that the effect of improving the penetration resistance by roughening the inner surface of the insertion hole or forming the concave portion (convex portion) can also be obtained when the heat pipe is expanded by heating in a heating furnace.

(Example 5) An exposed portion (110 m in length) of the heat pipe 5 of an assembled body manufactured in the same manner as in Example 1
m) Eight aluminum radiating fins (JISA1050, plate thickness: 0.2 mm) each having a 6.50 mm diameter hole formed by burring are inserted through 6 at intervals of 3 mm. The heat pipe 5 was plastically deformed in the diameter-expanding direction by heating for one minute to produce a heat sink.

For the twenty heat sinks obtained in Example 5, the presence or absence of deformation (distortion) of the heat pipe, the appearance of the joint between the heat pipe and the radiation fin (the presence or absence of deformation of the radiation fin), and the dimensional accuracy (outer diameter dimension) Was examined. As a result, no deformation (distortion) was observed in the heat pipe, and the appearance and dimensional accuracy of the joint between the heat pipe and the radiation fin were good. In addition, the pull-out resistance from the aluminum substrate insertion hole also satisfied a certain standard.

Example 6 As shown in FIG. 8, an aluminum plate having six heat pipe insertion holes 17 having an elliptical cross section (a short diameter of 3.2 mm and a long diameter of 8.7 mm) was extruded. Was cut into a length of 110 mm to form an aluminum substrate 18, and a corrugated fin 3 having a height of 15 mm was brazed to the surface of the aluminum substrate 18 to form a heat transfer member 19. Next, the portion arranged in the insertion hole 17 of the heat pipe having a circular cross section (outer diameter 6.35 mm) is pressed vertically to form an elliptical cross section (short diameter 3.0 mm, long diameter 8.5 mm). The elliptical section 21 of the heat pipe 20 is inserted into the insertion hole 17.
Through the heat pipe 20 of this assembly.
Aluminum radiating fins (J) with a 6.50 mm diameter hole formed by burring on the exposed part (length 110 mm)
ISA1050, plate thickness 0.2 mm) were inserted at an interval of 3 mm, placed in a heating furnace and heated at 270 ° C. for 20 minutes, and the heat pipe 5 was plastically deformed in the radial direction to produce a heat sink. The thickness of the aluminum substrate 18 was 3.3 mm thinner than the aluminum substrate of Example 5 because the short diameter of the through hole 17 was smaller than the diameter of the circular insertion hole.

For the twenty heat sinks obtained in Example 6, the presence or absence of deformation (distortion) of the heat pipe, the appearance of the joint between the heat pipe and the radiation fin (the presence or absence of deformation of the radiation fin), and the dimensional accuracy (outer diameter dimension) And the resistance of the heat pipe to the heat transfer member from the insertion hole was examined by the same method as in Example 5.

As a result, no deformation (distortion) was observed in the heat pipe, and the appearance and dimensional accuracy of the joint between the heat pipe and the radiation fin were good. Also, the withstand force from the aluminum substrate insertion hole satisfies a certain standard similarly to the case of the fifth embodiment. Thus, the heat transfer member (aluminum plate) having the heat pipe inserted into the heat pipe insertion hole with the elliptical cross section in comparison with the case of disposing the heat pipe in the circular cross section (Example 1) has a larger thickness. It can be seen that the heating temperature can be reduced when the heat pipe is plastically deformed in the radially expanding direction. In the sixth embodiment, only the portion embedded in the heat pipe insertion hole 17 has an elliptical shape, but the same effect can be obtained by making the entire heat pipe elliptical.

[0048]

As described above, according to the present invention, the exposed portion of the heat pipe is arranged in the heat pipe fixing hole of the fixing jig and fixed to expand the diameter of the heat pipe. (Distortion) is prevented. If the heat pipe fixing hole of the fixing jig is processed with high precision, the dimensional accuracy of the exposed portion of the heat pipe is improved. Also, since the diameter expansion of the exposed portion is suppressed by the fixing hole, the heat pipe in the heat pipe insertion hole of the heat transfer member is satisfactorily expanded,
The heat resistance of the heat pipe from the insertion hole is improved.
By performing the heating of the heat pipe by a heating element provided in the fixing jig, the time required for expanding the heat pipe 5 by heating is shortened, the productivity is increased, and the heating equipment is also reduced.
Temperature control can be performed with high accuracy.

When at least a part of the inner surface of the heat pipe insertion hole of the heat transfer member is roughened, frictional resistance is generated between the heat pipe and the roughened portion, so that the heat pipe can be more easily pulled out. When a concave portion or a convex portion is provided on the inner surface of the heat pipe insertion hole of the heat transfer member, the surface layer portion of the heat pipe that swells due to the heat expansion is engaged with the concave portion or the convex portion, and the heat pipe is resistant to slipping out. The properties are further improved. Therefore, it is possible to manufacture a heat sink in which the shape and dimensions of the exposed portion are excellent and the heat pipe does not come out of the insertion hole during use. Further, instead of the fixing jig, the heat pipe can be prevented from being deformed (distorted) even if the exposed portion of the heat pipe is suppressed by the inner surface of the hole formed in the heat radiating fin. There is no need to use a press-fitting machine, which is advantageous in terms of equipment and productivity.

When the heat pipe is embedded in the heat pipe insertion hole of the heat transfer member with an elliptical cross section, (1) the thickness of the heat transfer member can be reduced and the space can be saved as compared with the case where the heat pipe is embedded in a circular cross section. (2) The heat pipe is easily plastically deformed in the radially expanding direction, and the heating temperature when the heat pipe is plastically deformed can be lowered. Therefore, an industrially remarkable effect is achieved.

[Brief description of the drawings]

FIGS. 1A and 1B are an explanatory perspective view and an explanatory longitudinal sectional view, respectively, showing a first embodiment of the present invention.

FIGS. 2 (a) and 2 (b) are longitudinal sectional views showing a second embodiment of the present invention.

FIG. 3 is a longitudinal sectional view showing a third embodiment of the present invention.

FIG. 4 is a longitudinal sectional view showing a fourth embodiment of the present invention.

FIG. 5 is a longitudinal sectional view showing a fifth embodiment of the present invention.

FIG. 6 is a longitudinal sectional view showing a sixth embodiment of the present invention.

FIG. 7 is a longitudinal sectional view showing a seventh embodiment of the present invention.

FIG. 8 is a longitudinal sectional view showing an eighth embodiment of the present invention,
It is sectional drawing a and bb end view.

FIG. 9 is a perspective view showing the shape of a hole subjected to burring.

FIG. 10 is a perspective view illustrating a conventional method of attaching a heat pipe to a heat transfer member.

[Explanation of symbols]

REFERENCE SIGNS LIST 1 heat pipe insertion hole 2 aluminum substrate 3 radiating fin 4 heat transfer member 5 heat pipe 6 exposed portion of heat pipe 7 fixing jig 8 heat pipe fixing hole 9 open concave portion provided on inner surface of insertion hole of heat transfer member 10 heat transfer Closed recess provided on the inner surface of the insertion hole of the member 11 Open recess provided on the inner surface of the fixing hole of the fixing jig 12 Projection provided on the inner surface of the insertion hole of the heat transfer member 13 Heating furnace 14 Upper mold 15 of the fixing jig 15 Fixed Lower mold of jig 16 Roughened portion 17 Heat pipe insertion hole with elliptical cross section 18 Aluminum substrate with heat pipe insertion hole with elliptical cross section 19 Heat transfer member made of aluminum substrate with heat pipe insertion hole with elliptical cross section Reference Signs List 20 heat pipe having elliptical cross section 21 elliptical cross section of heat pipe 23 radiating fin 24 hole formed in radiating fin 25 burring processing on radiating fin More drilled holes

Claims (6)

[Claims] 1. A heat pipe in which a working fluid is sealed is inserted through a heat pipe insertion hole of a heat transfer member by exposing a part of the heat pipe, and the heat pipe is plastically deformed in a radially expanding direction. In the method of attaching a heat pipe to a heat transfer member in which the heat pipe is embedded in a heat pipe insertion hole of the heat transfer member, an exposed portion of the heat pipe is arranged in a heat pipe fixing hole of a fixing jig, and then the heat A method for attaching a heat pipe to a heat transfer member, wherein the heat pipe is heated and plastically deformed in a radially expanding direction. 2. The method according to claim 1, wherein the heat pipe is heated by a heating element provided on the fixing jig and is plastically deformed in a radially expanding direction. . 3. A friction resistance between the heat pipe and the inner surface of the insertion hole by roughening at least a part of the inner surface of the insertion hole of the heat pipe so that the surface roughness Ra is 0.1 to 40 μm. The method for mounting a heat pipe on a heat transfer member according to claim 1, wherein the heat pipe is hardly removed from the insertion hole. 4. A concave portion is provided on the inner surface of the heat pipe insertion hole of the heat transfer member, and a surface layer of the heat pipe is bulged in the concave portion, or a convex portion is provided on the inner surface of the heat pipe insertion hole of the heat transfer member. The method according to claim 1, wherein a surface layer of the heat pipe is swelled at a portion other than the convex portion, so that the heat pipe is hardly removed from the insertion hole. . 5. A heat pipe in which a working fluid is sealed is inserted through a heat pipe insertion hole of a heat transfer member by exposing a part of the heat pipe, and the heat pipe is plastically deformed in a radially expanding direction. In the method for attaching a heat pipe to a heat transfer member, wherein the heat pipe is embedded in a heat pipe insertion hole of the heat transfer member, the exposed portion of the heat pipe is passed through the holes of a plurality of perforated radiation fins, Then, the heat pipe is heated and plastically deformed in a radially expanding direction. 6. The heat pipe insertion hole of the heat transfer member and a cross-sectional shape of a portion embedded in the insertion hole of the heat pipe are elliptical.
The method for attaching a heat pipe to the heat transfer member according to any one of the above.