US20120227935A1

US20120227935A1 - Interconnected heat pipe assembly and method for manufacturing the same

Info

Publication number: US20120227935A1
Application number: US13/045,737
Authority: US
Inventors: Yu-Po HUANG
Original assignee: Kunshan Jue Chung Electronics Co
Current assignee: KUNSHAN JUE-CHUNG ELECTRONICS Co Ltd; Kunshan Jue Chung Electronics Co
Priority date: 2011-03-11
Filing date: 2011-03-11
Publication date: 2012-09-13

Abstract

The present invention relates to an interconnected heat pipe assembly and a method for manufacturing the same. The interconnected heat pipe assembly includes a first heat pipe and a second heat pipe. The first heat pipe comprises a first pipe, a first wick structure and a first working fluid. The first pipe has a hollow chamber and an opening. The first wick structure is arranged on inner walls of the hollow chamber. The first working fluid is filled in the hollow chamber. The second heat pipe is disposed through the opening in the first pipe with a portion of the second heat pipe being received in the hollow chamber. An air channel is formed between outer walls of the second heat pipe and inner walls of the first pipe. The present invention can conduct heat to a long distance and has an increased heat-conducting efficiency.

Description

BACKGROUND OF THE INVENTION

1. Field of the Invention
The present invention relates to a heat pipe assembly, in particular to an interconnected heat pipe assembly and a method for manufacturing the same.
2. Description of Prior Art
A heat pipe includes a sealed pipe, a wick structure arranged on an inner wall of the sealed pipe, and a working fluid filled in the sealed pipe. In use, one end of the heat pipe brought into thermal contact with a heat source is called as a heat-absorbing section (evaporating end), and the other end of the heat pipe away from the heat-absorbing end is called a heat-releasing section (condensing end). The heat generated by the heat source is absorbed by the working fluid in the heat-absorbing section of the heat pipe, so that the liquid-phase working fluid in the heat-absorbing section turns into a vapor phase. The vapor-phase working fluid flows toward the heat-releasing section due to a temperature difference in the heat pipe. The vapor-phase working fluid releases its latent heat to return to a liquid phase. The liquid-phase working fluid flows back to the heat-absorbing section along the wick structure inside the heat pipe. With the circulation and liquid-vapor phase change of the working fluid in the heat pipe, the heat generated by the heat source can be conducted from the heat-absorbing section to the heat-releasing section.
With the advancement of science and technology, the operating performance of electronic elements is increased greatly. As a result, the amount of heat generated by the electronic elements per unit of time is also increased substantially. Thus, when the working fluid in the heat-absorbing section of the heat pipe absorbs such a large amount of heat, the working fluid in the heat-absorbing section evaporates completely. However, the evaporating rate of the working fluid in the heat-absorbing section is much larger than the condensing rate of the working fluid in the heat-releasing section. Thus, the heat-absorbing section of the heat pipe may dry out after working for a period of time. In order to solve this problem, it is necessary to increase the size of the heat pipe so as to increase the volume of the working fluid contained therein. As a result, the electronic elements having such a large-sized heat pipe cannot be made more compact.
On the other hand, since the vapor-flowing rate in the heat pipe is larger than the liquid-reflowing rate in the wick structure, such a difference in rate becomes significant in a heat pipe of a long distance. As a result, the dry-out problem becomes more serious in a long heat pipe. Thus, it is an important issue for those skilled in this art to design a long heat pipe. On the other hand, the effective region of the heat pipe concentrates on the heat-absorbing section and the heat-releasing section only, and the rest portion of the heat pipe seems to serve as a transferring section. Thus, the heat-conducting efficiency of the whole heat pipe is restricted.
Therefore, it is an important issue for the present Inventor to solve the above-mentioned problems.

SUMMARY OF THE INVENTION

The present invention is to provide an interconnected heat pipe assembly, which is capable of conducting heat in a long distance and has an increased heat-conducting efficiency.
The present invention provides an interconnected heat pipe assembly, including:
a first heat pipe comprising a first pipe, a first wick structure and a first working fluid, the first pipe having a hollow chamber, the first wick structure being arranged on at least one inner wall of the hollow chamber, the first working fluid being filled in the hollow chamber; and
a second heat pipe comprising a second pipe, a second wick structure and a second working fluid, a portion of the second heat pipe being received and sealed in the hollow chamber of the first pipe, an air channel being formed between an outer wall of the second heat pipe and an inner wall of the first pipe.
The present invention is to provide a method for manufacturing an interconnected heat pipe assembly which is capable of conducting heat in a long distance and has an increased heat-conducting efficiency.
The present invention provides a method for manufacturing an interconnected heat pipe assembly, including steps of:
a) providing a first pipe, both ends of the first pipe being formed into a first degassing port and an opening;
b) providing a first wick structure, arranging the first wick structure on an inner wall of the first pipe;
c) providing a second heat pipe, disposing the second heat pipe through the opening of the first pipe with a portion of the second heat pipe being received in the first pipe;
d) providing a soldering apparatus, soldering a connecting portion between the opening of the first pipe and the second heat pipe by the soldering apparatus;
e) providing a first working fluid, filling the first working fluid into the first pipe through the first degassing port; and
f) providing a degassing and soldering apparatus, degassing the first pipe and then sealing the first degassing port to form a first heat pipe by the degassing and soldering apparatus.
The present invention provides a method for manufacturing an interconnected heat pipe assembly, including steps of:
a) providing a first pipe, both ends of the first pipe being formed into an opening and a second opening, the first pipe being provided with a degassing tube;
b) providing a first wick structure, arranging the first wick structure on an inner wall of the first pipe;
c) providing a second heat pipe, disposing the second heat pipe through the opening of the first pipe with a portion of the second heat pipe being received in the first pipe and the other portion of the second heat pipe penetrating the opening to form a second degassing port;
d) providing a third heat pipe, disposing the third heat pipe through the second opening of the first pipe with a portion of the third heat pipe being received in the first pipe and the other portion of the third heat pipe penetrating the second opening to form a third degassing port;
e) providing a soldering apparatus, soldering a connecting portion between the opening of the first pipe and the second heat pipe as well as a connecting portion between the second opening of the first pipe and the third heat pipe by the soldering apparatus;
f) providing a working fluid, filling the working fluid into the first pipe through the degassing tube, filling the working fluid into the second pipe through the second degassing port, filling the working fluid into the third pipe through the third degassing port; and
g) providing a degassing and soldering apparatus, degassing and sealing the first pipe, the second pipe and third pipe to form a first heat pipe, a second heat pipe and a third heat pipe respectively by the degassing and soldering apparatus.
According to another feature of the present invention, the present invention provides a pressing tool to press the first heat pipe and the second heat pipe to be flat. In this way, the second heat pipe is configured to support the inner walls of the first heat pipe.
In comparison with prior art, the present invention has the following advantageous features.
A portion of the second heat pipe is inserted into the first heat pipe in such a manner that an air channel is formed between outer walls of the second heat pipe and inner walls of the first heat pipe. The working fluid is filled in the hollow chamber of the heat pipe and the second heat pipe. The working fluid in the first heat pipe and the working fluid in the second heat pipe are respectively subjected to liquid/vapor phase change. Thus, the dry-out phenomenon occurred in conventional single heat pipe will not happen in the present invention. In other words, the working fluid in the first heat pipe and the working fluid in the second heat pipe can be used for heat exchange sufficiently. Further, the first heat pipe and the second heat pipe are formed with an independent hollow chamber respectively. Therefore, the interconnected heat pipe assembly of the present invention exhibits a larger heat-conducting efficiency than the conventional single heat pipe.
According to still another feature of the present invention, a pressing tool is used to press the first heat pipe and the second heat pipe to be flat with the second heat pipe being configured to support the inner walls of the first heat pipe. Thus, the flattened first heat pipe has a larger contact area than a conventional tubular heat pipe, thereby increasing the heat-conducting efficiency thereof. Further, the flattened first heat pipe reduces the overall thickness of the interconnected heat pipe assembly, thereby conforming to the requirements for compact design.

BRIEF DESCRIPTION OF DRAWING

FIG. 1 is a perspective view showing a first pipe of the present invention;

FIG. 2 is a side cross-sectional view showing that a core rod is disposed in the first pipe of the present invention;

FIG. 3 is a side cross-sectional view showing that the core rod is disposed in the first pipe of the present invention and a first wick structure is formed;

FIG. 4 is a side cross-sectional view showing the first heat pipe of the present invention;

FIG. 5 is a schematic view showing that a second heat pipe is to be disposed in the first pipe of the present invention;

FIG. 6 is a perspective view showing that the second heat pipe has been inserted into the first heat pipe of the present invention;

FIG. 7 is a side cross-sectional view showing that the second heat pipe has been inserted into the first heat pipe of the present invention;

FIG. 8 is a side cross-sectional view showing that a working fluid is filled in the first heat pipe of the present invention, and the first heat pipe and the second heat pipe are degassed;

FIG. 9 is a side cross-sectional view showing that the first heat pipe and the second heat pipe of the present invention are sealed;

FIG. 10 is a perspective view of FIG. 9;

FIG. 11 is a perspective view showing a second embodiment of the present invention;

FIG. 12 is an end cross0sectional view showing the second embodiment of the present invention;

FIG. 13 is a perspective view showing a third embodiment of the present invention;

FIG. 14 is a cross-sectional view of FIG. 13;

FIG. 15 is a perspective view showing a fourth embodiment of the present invention; and

FIG. 16 is a cross-sectional view of FIG. 15.

DETAILED DESCRIPTION OF THE INVENTION

The detailed description and technical contents of the present invention will become apparent with the following detailed description with reference to the accompanying drawings. It is noteworthy to point out that the drawings is provided for illustration only, but not intended to limit the scope of the present invention.
Please refer to FIGS. 1 to 10, which show the first embodiment of the present invention. The present invention provides an interconnected heat pipe assembly 1 and a method for manufacturing the same. In order to better understand the construction of the interconnected heat pipe assembly 1, the method of the present invention is described as follows according to the sequence of steps.
The method for manufacturing an interconnected heat pipe assembly of the present invention includes steps as follows.
a) providing a first pipe, both ends of the first pipe being formed into a first degassing port and an opening;
In the step a), as shown in FIG. 1, a first pipe 10 is provided, which is a hollow pipe having two open ends. Then, one end (left end in FIG. 1) of the first pipe 10 is narrowed to form a first degassing port 11. As shown in FIG. 2, a core rod W is disposed through the opening 12 into the first pipe 10. The profile and outer diameter of the core rod 100 are designed to be slightly smaller than the profile and inner diameter of the first pipe 10, thereby generating a gap between the first pipe 10 and the core rod 100.
b) providing a first wick structure, arranging the first wick structure on an inner wall of the first pipe;
In the step b), as shown in FIG. 3, the gap between the first pipe 10 and the core rod 100 is filled with a first wick structure 13. The first wick structure 13 is made by sintering metal powder at high temperature, thereby forming a porous first wick structure 13 on at least one inner wall of the first pipe 10. Of course, the first wick structure 12 may be made by other materials such as metallic woven meshes to have a spring-like, a groove-like, a post-like and a net-like construction. After the core rod 100 is removed, the first pipe 10 is formed with a hollow chamber 14 and the opening 12 away from the first degassing port 11. Further, one end of the first pipe 10 adjacent to the opening 12 is formed with a first tapered section 121.
c) providing a second heat pipe, disposing the second heat pipe through the opening of the first pipe with a portion of the second heat pipe being received in the first pipe;
In the step c), as shown in FIGS. 5 and 6, a second pipe 20 is provided. The outer diameter of the second pipe 20 is smaller than the inner diameter of the opening 12 of the first pipe 10, so that the second pipe 20 can be disposed through the opening 12 into the first pipe 10 with a portion of the second pipe 20 being received in the first pipe 10. Before disposing the second pipe 20 into the first pipe 10, the left end of the second pipe 20 is sealed first, and the right end of the second pipe 20 is narrowed to form a second degassing port 21. Then, by using a common method for manufacturing a heat pipe, metal powder is filled in the second degassing port 21 and sintered at high temperature, thereby forming a porous second wick structure 22 (FIG. 7) in the second pipe 20. Of course, the second wick structure 22 may be made by other materials such as metallic woven meshes having a spring-like, a groove-like, a post-like and a net-like construction.
d) providing a soldering apparatus, soldering and sealing a connecting portion between the opening of the first pipe and the second heat pipe by the soldering apparatus.
In the step d), as shown in FIG. 7, after the second pipe 20 is inserted into the hollow chamber 14 of the first pipe 10, a soldering apparatus (not shown) is used to solder and seal the opening 12 of the first pipe 10, thereby sealing the first tapered section 121 of the first pipe 10 and the second pipe 20 together at the opening 12.
e) providing a first working fluid, filling the first working fluid in the first pipe via the first degassing port; and f) providing a degassing and soldering apparatus, degassing and sealing the first pipe to form a first heat pipe by the degassing and soldering apparatus.
In the steps e) and f), as shown in FIG. 8, a first working fluid 15 and a second working fluid 23 (such as water) are filled in the first pipe 10 via the first degassing port 11 and filled in the second pipe 20 via the second degassing port 21. Then, a degassing and soldering apparatus (not shown) is used to degas the first pipe 10 and the second pipe 20. Finally, the first degassing port 11 and the second degassing port 21 are soldered and sealed to form a first heat pipe 100 shown in FIG. 9 and a second heat pipe 200 shown in FIG. 10 respectively. A portion of the second heat pipe 200 is received and sealed in the hollow chamber 14 in such a manner that an air channel S₁₂is formed between an outer wall of the second heat pipe 200 and an inner wall of the first pipe 10. In addition to water, the first working fluid 15 and the second working fluid 23 may be any one selected from a group including inorganic compounds, alcohols, ketones, liquid metals, coolants, organic compounds and mixtures thereof.
Of course, it can be contemplated that the second pipe 20 may be made into the second heat pipe 200 first, and then it is disposed into the first pipe 10. Next, the connecting portion between the second heat pipe 200 and the first pipe 10 is soldered and sealed. Finally, the first pipe 10 is subjected to the filling of the first working fluid 15, the degassing and soldering to finish the first heat pipe 100. In this way, the interconnected heat pipe assembly 1 of the present invention can be also achieved.
Please refer to FIG. 9. The heat-conducting principle of the interconnected heat pipe assembly 1 of the present invention will be described. When a section of the first heat pipe 100 near the first degassing port 11 is adhered to a heat source (not shown), the heat generated by the heat source is absorbed by the section of the first heat pipe 100, so that the first working fluid 15 inside the section of the first heat pipe 100 absorbs the heat to evaporate. Then, the vapor-phase first working fluid 15 flows toward the air channel S₁₂and heat-exchanges with a portion of the second heat pipe 200 overlapped with the first heat pipe 100, so that the vapor-phase first working fluid 15 in the air channel S₁₂releases its latent heat to condense. Then, the condensed working fluid 15 flows back to the section of the first heat pipe 100 near the first degassing port 11. At the same time, the second working fluid 23 in the portion of the second heat pipe 200 overlapped with the first heat pipe 100 absorbs the heat released from the vapor-phase first working fluid 15 to evaporate. Then, the vapor-phase second working fluid 23 flows toward another portion of the second heat pipe 200 near the second degassing port 21 and releases its latent heat to return to liquid phase. In this way, the heat generated by the heat source can be conducted from the first heat pipe 100 to the second heat pipe 200 and finally dissipated to the outside. Thus, if a plurality of heat-dissipating fins (not shown) is connected to the portion of the second heat pipe 200 near the second degassing port 21, the heat generated by the heat source can be quickly conducted from the first heat pipe 100 to the second heat pipe 200 and dissipated to the outside via the heat-dissipating fins.
Please refer to FIG. 11, which shows the second embodiment of the present invention. The difference between the second embodiment and the first embodiment lies in that: each of the first heat pipe 100 and the second heat pipe 200 in the first embodiment is formed into a tubular shape. In the second embodiment, a pressing tool (not shown) is provided to press the first heat pipe 100 and the second heat pipe 200 to be flat, thereby obtaining a flat first heat pipe 100′ and a flat second heat pipe 200′. The steps of the method in the second embodiment are substantially the same as those of the method in the first embodiment except for an additional step of pressing the first heat pipe 100 and the second heat pipe 200 into a flat heat pipe 100′ and a flat second heat pipe 200′. Although FIG. 11 shows that the first heat pipe 100′ and the second heat pipe 200′ are pressed to be flat in their whole length, it can be contemplated that the pressing may be performed on only a portion of the first heat pipe 100′ and the second heat pipe 200′.
It can be seen from FIG. 12 that, after pressing, the vertical outer walls of the first pipe 10′ expand laterally, thereby increasing the contact area between the vertical outer walls of the first pipe 10′ and a heat source (not shown) greatly. Thus, the heat generated by the heat source can be conducted from the first heat pipe 100′ to the second heat pipe 200′ more quickly. On the other hand, after pressing, the vertical inner walls of the first pipe 10′ are brought into tight contact with the vertical outer walls of the second heat pipe 200′, that is, the vertical outer walls of the second heat pipe 200′ are brought into tight contact with the first wick structure 13′ inside the first pipe 10′, thereby increasing the supporting strength of the interconnected heat pipe assembly V. Since the first pipe 10′ is pressed to be flat, two air channels S₁₂′ are formed between the lateral inner walls of the first pipe 10′ and the lateral outer walls of the second heat pipe 200′.
Please refer to FIGS. 13 and 14, which show the interconnected heat pipe assembly 1 a of the third embodiment of the present invention. The difference between the third embodiment and the second embodiment lies in that: the third embodiment further comprises a third heat pipe 300′ connected to the second heat pipe 200′ and away from the first heat pipe 100′. The size of the third heat pipe 300′ is larger than that of the second heat pipe 200′, thereby forming the interconnected heat pipe assembly 1 a having a “big-small-big” construction.
In the interconnected heat pipe assembly 1 a, the steps of the method for manufacturing the first heat pipe 100′ and the second heat pipe 200′ are substantially the same as those in the previous embodiments, and thus the redundant description is omitted for clarity. In the following, only the method for manufacturing the third heat pipe 300′ is described.
A third pipe 30′ and a third wick structure 35′ are provided. The third wick structure 35′ is arranged on an inner wall of the third pipe 30′. The third pipe 30′ has a chamber 33′ and a pipe hole 32′. One end of the second heat pipe 200′ away from the first heat pipe 100′ is disposed through the pipe hole 32′ into the third pipe 30′, so that the other portion of the second heat pipe 200′ is received and sealed in the chamber 33′. An air channel S₂₃′ is formed between the outer wall of the other portion of the second heat pipe 200′ and the inner wall of the third pipe 30′. One end of the third pipe 30′ away from the pipe hole 32′ is narrowed to form a third degassing port 31′. The third pipe 30′ is formed with a third tapered section 321′ near the pipe hole 32′. The soldering apparatus is used to seal the third pipe 30′ and the second heat pipe 200′, so that the third tapered section 321′ and the second heat pipe 200′ are soldered together at the pipe hole 32′. A third working fluid 36′ is provided and filled in the third pipe 30′. The degassing and soldering apparatus is used to degas the third pipe 30′ and seal the third degassing port 31′, thereby finishing the third heat pipe 300′. A pressing tool is provided to press at least one portion of the first heat pipe 100′, the second heat pipe 200′ and the third heat pipe 300′ to be flat.
The interconnected heat pipe assembly 1 a of the second embodiment has a primary advantage of further extending the length of the second heat pipe 200′ for heat conduction to a longer distance. The third heat pipe 300′ is put on a portion of the second heat pipe 200′. An air channel S₂₃′ is also formed between the third heat pipe 300′ and the second heat pipe 200′ like the first embodiment. The portion of the second heat pipe 200′ located in the third heat pipe 300′ serves as a heat-releasing section for heat-exchanging with the third heat pipe 300′. Thus, the heat is dissipated to the outside via the outer surface of the third heat pipe 300′. In other words, the third heat pipe 300′ not only increases the heat-conducting length of the second heat pipe 200′, but also increases the heat-dissipating area of the second heat pipe 200′. Thus, the heat-dissipating effect is improved greatly.
Please refer to FIGS. 15 and 16, which show the interconnected heat pipe assembly 1 b of the fourth embodiment of the present invention. The difference between the fourth embodiment and the second embodiment lies in that: the fourth embodiment further comprises a third heat pipe 300″ connected to the first heat pipe 100″ and away from the second heat pipe 200″. The size of the third heat pipe 300″ is smaller than that of the first heat pipe 100″. In other words, two open ends of the big first heat pipe 100″ are inserted by a small second heat pipe 200″ and a small third heat pipe 300″ respectively, thereby forming an interconnected heat pipe assembly 1 b having a “small-big-small” construction.
The method of the third embodiment is described as follows. First, a first pipe 10″ is provided. The middle section of the first pipe 10″ is provided with a degassing tube 11″. Both ends of the first pipe 10″ are formed with an opening 12″ and a second opening 16″. The first pipe 10″ is formed with a tapered section 161″ near the second opening 16″. Then, a first wick structure 13″ is filled into the first pipe 10″ and sintered to be adhered onto inner walls of the first pipe 10″. Then, a second pipe 20″ and a third pipe 30″ are provided. A second wick structure 22″ is arranged on inner walls of the second pipe 20″, and a third wick structure 35″ is arranged on inner walls of the third pipe 30″. The second pipe 20″ is narrowed to form a second degassing port 21″, and the third pipe 30″ is narrowed to form a third degassing port 31″. The second pipe 20″ is disposed through the opening 12″ into the first heat pipe 10″, and the third pipe 30″ is disposed through the second opening 16″ into the first heat pipe 10″. The second pipe 20″ and the first tapered section 121″ are soldered together at the opening 12″. The third pipe 30″ and the tapered section 161″ are soldered together at the second opening 16″. The first working fluid 15″ is filled in the first pipe 10″ via the degassing tube 11″. The second working fluid 23″ is filled in the second pipe 20 “ via the second degassing port 21”. The third working fluid 36″ is filled in the third pipe 30″ via the third degassing port 31″. The first pipe 10″, the second pipe 20″ and the third pipe 30″ are respectively degassed via the first degassing port 11″, the second degassing port 21″ and the third degassing port 31″, thereby finishing the first heat pipe 100″, the second heat pipe 200″ and the third heat pipe 300″. Finally, a pressing tool is provided to press at least one portion of the first heat pipe 100″, the second heat pipe 200″ and the third heat pipe 300″. After pressing, air channels S₁₂″ are formed between the lateral inner walls of a portion of the first pipe 10″ and the lateral outer walls of the second heat pipe 200″. Air channels S₁₃″ are formed between the lateral inner walls of the other portion of the first pipe 10″ and the lateral outer walls of the third heat pipe 300″.
It can be seen from FIG. 16 that, when the first heat pipe 100″ is brought into thermal contact with a heat source, the heat pipe 100″ absorbs the heat of the heat source to evaporate the first working fluid within the first pipe 100″, thereby heating a portion of the second heat pipe 200″ and a portion of the third heat pipe 300″ within the first heat pipe 100″. As a result, a section of the second heat pipe 200″ near the second degassing port 21″ and a section of the third heat pipe 300″ near the third degassing port 31″ serve as a heat-releasing section respectively. In other words, the interconnected heat pipe assembly 1 b can conduct the heat of a heat source located in the center of the assembly 1 b to its both ends.
Of course, those skilled in this art can easily contemplate to connect at least one heat pipe 100″ to the interconnected heat pipe assembly 1 b shown in FIG. 15 to form a four-piece or five-piece interconnected heat pipe assembly.
Although the present invention has been described with reference to the foregoing preferred embodiments, it will be understood that the invention is not limited to the details thereof. Various equivalent variations and modifications can still occur to those skilled in this art in view of the teachings of the present invention. Thus, all such variations and equivalent modifications are also embraced within the scope of the invention as defined in the appended claims.

Claims

1. An interconnected heat pipe assembly, including:

a first heat pipe comprising a first pipe, a first wick structure and a first working fluid, the first pipe having a hollow chamber, the first wick structure being arranged on at least one inner wall of the hollow chamber, the first working fluid being filled in the hollow chamber; and

a second heat pipe comprising a second pipe, a second wick structure and a second working fluid, a portion of the second heat pipe being received and sealed in the hollow chamber of the first pipe, an air channel being formed between an outer wall of the second heat pipe and an inner wall of the first pipe.

2. The interconnected heat pipe assembly according to claim 1, wherein the first pipe is provided with an opening, one end of the first pipe near the opening is formed with a first tapered section, the other end of the first pipe away from the opening is formed with a first degassing port, the first tapered section and a portion of the second heat pipe are soldered together at the opening.

3. The interconnected heat pipe assembly according to claim 2, wherein the other portion of the second heat pipe penetrates the opening to form a second degassing port.

4. The interconnected heat pipe assembly according to claim 3, wherein the first heat pipe and the second heat pipe are pressed to be flat in such a manner that vertical inner walls of the first pipe are brought into tight contact with vertical outer walls of the second heat pipe, the air channel is formed between lateral inner walls of the first pipe and lateral outer walls of the second heat pipe.

5. The interconnected heat pipe assembly according to claim 4, further comprising a third heat pipe connected to the second heat pipe and away from the first heat pipe.

6. The interconnected heat pipe assembly according to claim 5, wherein the third heat pipe comprises a third pipe and a third wick structure arranged on an inner wall of the third pipe, the third pipe has a chamber and a pipe hole, one end of the second heat pipe away from the first heat pipe is disposed through the pipe hole into the third pipe with the other portion of the second heat pipe being received and sealed in the chamber, an air channel is formed between outer walls of the other portion of the second heat pipe and inner walls of the third pipe.

7. The interconnected heat pipe assembly according to claim 6, wherein one end of the third pipe near the pipe hole is formed with a third tapered section, the other end of the third pipe away from the pipe hole is formed with a third degassing port, the third tapered section and the second heat pipe are soldered together at the pipe hole.

8. The interconnected heat pipe assembly according to claim 4, further comprising a third heat pipe connected to the first heat pipe and away from the second heat pipe.

9. The interconnected heat pipe assembly according to claim 8, wherein one end of the first pipe away from the opening is formed with a second opening, the third heat pipe comprises a third pipe and a third wick structure arranged on an inner wall of the third pipe, the third heat pipe is disposed through the second opening into the first pipe with a portion of the third heat pipe being received and sealed in the hollow chamber, another air channel is formed between outer walls of the third heat pipe and inner walls of the first pipe.

10. The interconnected heat pipe assembly according to claim 9, wherein one end of the first pipe near the second opening is formed with a tapered section, a middle portion of the first pipe is provided with a degassing tube, the tapered section and the third heat pipe are soldered together at the second opening, the other portion of the third heat pipe penetrates the second opening to form a third degassing port.

11. A method for manufacturing an interconnected heat pipe assembly, including steps of:

a) providing a first pipe, both ends of the first pipe being formed into a first degassing port and an opening;

b) providing a first wick structure, arranging the first wick structure on an inner wall of the first pipe;

c) providing a second heat pipe, disposing the second heat pipe through the opening of the first pipe with a portion of the second heat pipe being received in the first pipe;

d) providing a soldering apparatus, soldering a connecting portion between the opening of the first pipe and the second heat pipe by the soldering apparatus;

e) providing a first working fluid, filling the first working fluid into the first pipe through the first degassing port; and

f) providing a degassing and soldering apparatus, degassing the first pipe and then sealing the first degassing port to form a first heat pipe by the degassing and soldering apparatus.

12. The method according to claim 11, further including a step of providing a pressing tool, and pressing at least one portion of the first heat pipe and the second heat pipe to be flat by the pressing tool.

13. The method according to claim 11, further including steps of:

g) providing a third pipe, both ends of the third pipe being formed with a third degassing port and a pipe hole;

h) providing a third wick structure, arranging the third wick structure on an inner wall of the third pipe;

j) narrowing the third degassing port, disposing a portion of the second heat pipe away from the first pipe through the pipe hole into the third pipe;

j) soldering a connecting portion between the third pipe and the second heat pipe by the soldering apparatus;

k) providing a third working fluid, filling the third working fluid into the third pipe; and

1) degassing the third pipe via the third degassing port by the degassing and soldering apparatus, sealing the third pipe by the soldering apparatus to form a third heat pipe.

14. The method according to claim 13, further including a step of providing a pressing tool, and pressing at least one portion of the first heat pipe, the second heat pipe and the third heat pipe to be flat by the pressing tool.

15. A method for manufacturing an interconnected heat pipe assembly, including steps of:

a) providing a first pipe, both ends of the first pipe being formed into an opening and a second opening, the first pipe being provided with a degassing tube;

c) providing a second heat pipe, disposing the second heat pipe through the opening of the first pipe with a portion of the second heat pipe being received in the first pipe and the other portion of the second heat pipe penetrating the opening to form a second degassing port;

d) providing a third heat pipe, disposing the third heat pipe through the second opening into the first pipe with a portion of the third heat pipe being received in the first pipe and the other portion of the third heat pipe penetrating the second opening to form a third degassing port;

e) providing a soldering apparatus, soldering a connecting portion between the opening of the first pipe and the second heat pipe as well as a connecting portion between the second opening of the first pipe and the third heat pipe by the soldering apparatus;

f) providing a working fluid, filling the working fluid into the first pipe through the degassing tube, filling the working fluid in the second pipe through the second degassing port, filling the working fluid in the third pipe through the third degassing port; and

g) providing a degassing and soldering apparatus, degassing and sealing the first pipe, the second pipe and third pipe to form a first heat pipe, a second heat pipe and a third heat pipe respectively by the degassing and soldering apparatus.

16. The method according to claim 15, further including a step of: providing a pressing tool, and pressing at least one the first heat pipe, the second heat pipe and the third heat pipe to be flat by the pressing tool.