U.S. patent application number 16/549895 was filed with the patent office on 2019-12-12 for heat pipe.
The applicant listed for this patent is DELTA ELECTRONICS, INC.. Invention is credited to Chiu-Kung CHEN, Shih-Lin HUANG, Sheng-Hua LUO, Ti-Jun WANG.
Application Number | 20190376748 16/549895 |
Document ID | / |
Family ID | 56078967 |
Filed Date | 2019-12-12 |
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United States Patent
Application |
20190376748 |
Kind Code |
A1 |
HUANG; Shih-Lin ; et
al. |
December 12, 2019 |
HEAT PIPE
Abstract
A heat pipe comprises a tube and a wick structure. The tube
includes a hollow chamber and has two sealed ends along an axial
direction. The wick structure is disposed in the hollow chamber and
extended along the axial direction of the tube. The wick structure
has a first section near one of the sealed ends, a third section
near the other of the sealed ends, and a second section between the
first and third sections. The second section is greater than the
first and third sections.
Inventors: |
HUANG; Shih-Lin; (Taoyuan
City, TW) ; CHEN; Chiu-Kung; (Taoyuan City,, TW)
; LUO; Sheng-Hua; (Taoyuan City, TW) ; WANG;
Ti-Jun; (Taoyuan City, TW) |
|
Applicant: |
Name |
City |
State |
Country |
Type |
DELTA ELECTRONICS, INC. |
Taoyuan City |
|
TW |
|
|
Family ID: |
56078967 |
Appl. No.: |
16/549895 |
Filed: |
August 23, 2019 |
Related U.S. Patent Documents
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Application
Number |
Filing Date |
Patent Number |
|
|
14818716 |
Aug 5, 2015 |
|
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|
16549895 |
|
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Current U.S.
Class: |
1/1 |
Current CPC
Class: |
F28D 15/046 20130101;
F28D 15/0233 20130101 |
International
Class: |
F28D 15/04 20060101
F28D015/04 |
Foreign Application Data
Date |
Code |
Application Number |
Nov 28, 2014 |
CN |
201410709251.7 |
Claims
1. A heat pipe, comprising: a tube including a hollow chamber and
having two sealed ends along an axial direction; and a wick
structure disposed in the hollow chamber and extended along the
axial direction of the tube, wherein the wick structure has a first
section near one of the sealed ends, a third section near the other
of the sealed ends, and a second section between the first and
third sections; and the second section is greater than the first
and third sections.
2. The heat pipe as recited in claim 1, wherein the tube is
cylindrical, elliptic or rectangular.
3. The heat pipe as recited in claim 1, wherein the sections of the
wick structure along the axial direction of the tube have a
continuous edge.
4. The heat pipe as recited in claim 1, wherein the sections of the
wick structure along the axial direction of the tube have a
discontinuous edge.
5. The heat pipe as recited in claim 1, wherein the wick structure
includes at least a support portion pressing an inner wall of the
tube.
6. The heat pipe as recited in claim 1, wherein the wick structure
is disconnected to the two sealed ends of the tube in the axial
direction, and a cross-sectional area of the wick structure in the
axial direction is cross-shaped.
7. The heat pipe as recited in claim 1, wherein the wick structure
has a center part thicker than two adjacent parts of the wick
structure along a radial direction perpendicular to the axial
direction, and the center part does not contact an upper wall of
the tube.
8. A heat pipe, comprising: a tube including a hollow chamber and
having two sealed ends along an axial direction; and a wick
structure disposed in the hollow chamber and extended along the
axial direction of the tube, wherein the wick structure has a first
section near one of the sealed ends, a third section near the other
of the sealed ends, and a second section between the first and
third sections; and the second section is less than the first and
third sections.
9. The heat pipe as recited in claim 8, wherein the tube is
cylindrical, elliptic or rectangular.
10. The heat pipe as recited in claim 8, wherein the sections of
the wick structure along the axial direction of the tube have a
continuous edge.
11. The heat pipe as recited in claim 8, wherein the sections of
the wick structure along the axial direction of the tube have a
discontinuous edge.
12. The heat pipe as recited in claim 8, wherein the wick structure
includes at least a support portion pressing an inner wall of the
tube.
13. The heat pipe as recited in claim 8, wherein the wick structure
is disconnected to the two sealed ends of the tube in the axial
direction, and a cross-sectional area of the wick structure in the
axial direction is cross-shaped.
14. A heat pipe, comprising: a tube including a hollow chamber and
having two sealed ends along an axial direction; and a wick
structure disposed in the hollow chamber and extended along the
axial direction of the tube, wherein the wick structure has a first
section near one of the sealed ends, a third section near the other
of the sealed ends, and a second section between the first and
third sections; and the first section is greater than the second
section, and the second section is greater than the third
section.
15. The heat pipe as recited in claim 14, wherein the tube is
cylindrical, elliptic or rectangular.
16. The heat pipe as recited in claim 14, wherein the sections of
the wick structure along the axial direction of the tube have a
continuous edge.
17. The heat pipe as recited in claim 14, wherein the sections of
the wick structure along the axial direction of the tube have a
discontinuous edge.
18. The heat pipe as recited in claim 14, wherein the wick
structure includes at least a support portion pressing an inner
wall of the tube.
19. The heat pipe as recited in claim 14, wherein the wick
structure is disconnected to the two sealed ends of the tube in the
axial direction, and a cross-sectional area of the wick structure
in the axial direction is cross-shaped.
Description
CROSS REFERENCE TO RELATED APPLICATIONS
[0001] This application is a Continuation Application (CA) of an
earlier filed, pending, application, having application Ser. No.
14/818,716 and filed on Aug. 5, 2015, the content of which,
including drawings, is expressly incorporated by reference
herein.
BACKGROUND OF THE INVENTION
Field of Invention
[0002] The invention relates to a heat pipe and, in particular, to
a heat pipe with better performance.
Related Art
[0003] A conventional heat pipe is mainly composed of a sealed
metal pipe, a wick core structure inside the metal pipe and a
heat-transfer fluid filled in the metal pipe, and besides, a proper
vacuum degree is kept inside the metal pipe to lower down the
trigger-temperature-difference of the heat pipe. In the heat pipe,
the evaporator of the heat pipe is disposed at the heat source so
that the heat generated by the heat source can evaporate the fluid
(liquid phase) in the pipe into the vapor (vapor phase). The
generated vapor is driven by the vapor pressure difference to flow
to the condenser of the heat pipe and then condenses back to the
liquid phase after releasing the latent heat, and lastly is driven
by the capillarity to go back to the evaporator through the wick
core structure. Thereby, the heat pipe can transfer the heat to the
outside rapidly.
[0004] Due to its simple structure, high transfer performance and
low thermal resistance, the heat pipe has been applied to the
electronic field or other heat-dissipation fields for a long time.
However, because the electronic product is continuously enhanced in
portability, lightness and thinness, 4K image, 4G transmission and
more adding functions, the generated heat thereof is raised
increasingly. Therefore, the conventional heat pipe can't meet the
requirement of the high heat and high heat flux anymore.
Accordingly, the heat pipe needs to be further enhanced in
performance, for example, the manufacturing method of the wick core
needs to be improved so as to enhance the capillarity of the wick
structure.
[0005] The conventional wick core structure of the heat pipe is
made by disposing a core rod in the metal pipe to fix the metal
powder and also formed by the high sintering, so that the metal
powder can be attached to the whole or partial inner wall of the
metal pipe. However, the core rod has a high cost and may be
damaged during the process of the sintering or removing the core
rod, and even the wick structure will also be damaged. Therefore,
the performance of the heat pipe will be reduced.
[0006] Furthermore, the factors of the influence of the wick core
on the heat pipe performance mainly include: the thickness of the
sintering layer, porosity, permeability and powder diameter. The
above factors will affect the heat pipe during the water injection
process or the vacuum process and further affect the performance of
the heat pipe. In the heat pipe design, the thickness of the
sintering layer and the powder diameter can be determined by the
conventional method, but the porosity and permeability only can be
estimated by experience. If the data of the porosity and
permeability need to be obtained, they can be measured just after
the sintering process. In other words, the yield of the wick core
structure is still hard to be controlled accurately.
[0007] Although the wick core structure formed by the sintering has
been gradually replaced by the wick structure formed by the groove,
mesh or fine fiber in the current manufacturing of the thin-type
heat pipe, the capillarity of the wick structure formed by the
sintering is far greater than that of the wick structure formed by
the groove, in consideration of the heat transfer capability.
Besides, the heat resistance generated by the sintered-type heat
pipe is relatively lower. In other words, although the
sintered-type heat pipe has the insuperable problem, it still has
the space of development, in consideration of its advantage of the
heat transfer capability.
[0008] The wick core structure of a conventional heat pipe is
approximately formed as shown in FIGS. 1A and 1B, wherein FIG. 1A
is a schematic diagram of a part of the appearance of a
conventional heat pipe and FIG. 1B is a schematic sectional diagram
of the heat pipe in FIG. 1A in the radial direction. The heat pipe
H includes a pipe 1 and a wick structure 2. The pipe 1 has an
elliptic section and includes a hollow chamber 10, and the wick
structure 2 is disposed in the hollow chamber 10 and extended along
the axial direction D1 of the pipe 1. Otherwise, as shown in FIGS.
2A to 2H, the pipes 1a, 1b, 1c, 1d of the heat pipes H1, H2, H3, H4
all have rectangular sections, and besides, for the heat pipes H1,
H1, H2, H3, H4, each of the sections of the wick structures 2, 2a,
2b, 2c, 2d in the redial direction D2 of the pipes 1, 1a, 1b, 1c,
1d has a uniform shape and area between the two ends of each of the
pipes 1, 1a, 1b, 1c, 1d. However, in the practical applications,
the above-mentioned heat pipe form is hard to meet the
heat-dissipation requirements of different electronic devices, and
also the desired heat-dissipation effect can't be obtained.
[0009] Therefore, it is an important subject to provide a heat pipe
where the wick structure can be disposed according to the
performance requirement and the porosity and permeability of the
wick structure can be effectively controlled, so as to enhance the
yield and heat transfer performance of the heat pipe.
SUMMARY OF THE INVENTION
[0010] In view of the foregoing subject, an objective of the
invention is to provide a heat pipe where the wick structure can be
disposed according to the performance requirement and the porosity
and permeability of the wick structure can be effectively
controlled, so as to enhance the yield and heat transfer
performance of the heat pipe.
[0011] To achieve the above objective, a heat pipe according to the
invention comprises a pipe and at least a wick structure. The pipe
includes a hollow chamber. The wick structure is disposed in the
hollow chamber and extended along an axial direction of the pipe. A
section of the wick structure along the axial direction is not a
uniform section between two ends of the pipe.
[0012] In one embodiment, the pipe is a cylindrical pipe, an
elliptic pipe or a rectangular pipe.
[0013] In one embodiment, the wick structure is formed outside the
pipe.
[0014] In one embodiment, the section of the wick structure along
the axial direction of the pipe has a continuous edge.
[0015] In one embodiment, the section of the wick structure along
the axial direction of the pipe has a discontinuous edge.
[0016] In one embodiment, the heat pipe further comprises a
plurality of wick structures which are disposed adjacent to each
other in the pipe.
[0017] In one embodiment, each of the wick structures includes at
least a support portion pressing an inner wall of the pipe.
[0018] To achieve the above objective, a heat pipe according to the
invention comprises a pipe and at least a wick structure. The pipe
includes a hollow chamber. The wick structure is disposed in the
hollow chamber and extended along an axial direction of the pipe. A
section of the wick structure along a radial direction of the pipe
is not a uniform section.
[0019] To achieve the above objective, a heat pipe according to the
invention comprises a pipe and at least a wick structure. The pipe
includes a hollow chamber. The wick structure is disposed in the
hollow chamber and extended along an axial direction of the pipe. A
section of the wick structure along the axial direction is not a
uniform section between two ends of the pipe. A section of the wick
structure along a radial direction of the pipe is not a uniform
section.
[0020] Summarily, the wick structure of the heat pipe of this
invention can be varied in form along the axial direction of the
pipe so as to meet the structure requirement of the evaporator,
heat insulator and condenser of the heat pipe and can be adjusted
according to the space and performance of the pipe of the heat pipe
or according to the actual heat-dissipation requirement.
[0021] The conventional wick core structure of the heat pipe is
made by disposing a core rod in the metal pipe to fix the metal
powder and also formed by the high sintering, but the core rod has
a high cost and may be damaged during the process of the sintering
or removing the core rod, and even the wick structure may be also
damaged, so that the performance of the heat pipe is reduced.
However, the wick structure of this embodiment is formed on the
outside firstly, and the form of the wick structure can be designed
according to the performance requirement and won't be limited by
the core rod required for the conventional process. Besides,
favorably, the quality of the wick structure can be examined
outside the pipe firstly to eliminate the defective products in
advance so as to enhance the yield of the heat pipe.
BRIEF DESCRIPTION OF THE DRAWINGS
[0022] The invention will become more fully understood from the
detailed description and accompanying drawings, which are given for
illustration only, and thus are not limitative of the present
invention, and wherein:
[0023] FIG. 1A is a schematic diagram of a part of the appearance
of a conventional heat pipe;
[0024] FIG. 1B is a schematic sectional diagram of the heat pipe in
FIG. 1A in the radial direction;
[0025] FIGS. 2A, 2C, 2E, 2G are schematic diagrams of a part of the
appearances of different conventional heat pipes;
[0026] FIGS. 2B, 2D, 2F, 2H are schematic sectional diagram of the
heat pipes in FIGS. 2A, 2C, 2E, 2G in the radial direction;
[0027] FIG. 3A is a schematic diagram of the appearance of the heat
pipe of an embodiment of the invention;
[0028] FIG. 3B is a schematic sectional diagram of the heat pipe
taken along the line A-A in FIG. 3A;
[0029] FIGS. 3C and 3D are schematic sectional diagrams taken along
the line A-A of the heat pipe of FIG. 3A according to different
embodiments of the invention;
[0030] FIG. 4A is a schematic diagram of the appearance of the heat
pipe of another embodiment of the invention;
[0031] FIGS. 4B, 4C, 4D are schematic sectional diagrams of the
heat pipe in FIG. 4A taken along the line B-B according to
different embodiments;
[0032] FIG. 4E is a schematic sectional diagram of the heat pipe in
FIG. 4A taken along the line B'-B';
[0033] FIG. 5A is a schematic diagram of the appearance of the heat
pipe of another embodiment of the invention;
[0034] FIGS. 5B and 5D are schematic perspective sectional diagrams
of the heat pipe in FIG. 5A taken along the line C-C according to
different embodiments;
[0035] FIGS. 5C and 5E are schematic sectional diagrams of the heat
pipes of FIGS. 5B and 5D respectively;
[0036] FIG. 6A is a schematic diagram of a part of the appearance
of the heat pipe of an embodiment of the invention;
[0037] FIG. 6B is a schematic sectional diagram of the heat pipe in
FIG. 6A taken along the line D-D; and
[0038] FIG. 7 is a schematic sectional diagram of the heat pipe of
another embodiment of the invention.
DETAILED DESCRIPTION OF THE INVENTION
[0039] The present invention will be apparent from the following
detailed description, which proceeds with reference to the
accompanying drawings, wherein the same references relate to the
same elements.
[0040] FIG. 3A is a schematic diagram of the appearance of the heat
pipe of an embodiment of the invention, and FIG. 3B is a schematic
sectional diagram of the heat pipe taken along the line A-A in FIG.
3A. As shown in FIGS. 3A and 3B, in this embodiment, the heat pipe
H5 includes a pipe 1e and at least a wick structure 2e. A single
wick structure 2e is illustrated as an example herein. The pipe 1e
has a hollow chamber 10e, and the wick structure 2e is disposed in
the hollow chamber 10e and extended along the axial direction D1 of
the pipe 1e. The pipe 1e is a flat and cylindrical thin-type hollow
tube. The pipe 1e can be made by, for example, copper, silver,
aluminum, their alloy or other metal materials with well heat
transfer property. In the practical application, in addition to the
wick structure 2e, a working fluid (not shown) is also disposed in
the pipe 1e and can be any fluid helping the evaporation and heat
dissipation, such as inorganic compounds, alcohols, ketones, liquid
metal, refrigerant, organic compounds or their any mixture.
Moreover, the pipe 1e is not limited here in shape or dimensions,
which can be a cylindrical tube or rectangular tube and can be
determined according to the surrounding environment, space, heat
transfer requirement or temperature.
[0041] As shown in FIGS. 3A and 3B, the wick structure 2e of this
embodiment is formed outside the pipe 1e. In detail, the wick
structure 2e is formed outside the pipe 1e first, and can be formed
by the high sintering and/or injection molding, but this invention
is not limited thereto. Besides, before the wick structure 2e is
disposed to the pipe 1e, the porosity and permeability thereof are
properly controlled by the forming method so as to enhance the
capillarity of the wick structure, and therefore the amount of the
working fluid flowing back to the evaporator can be increased and
the maximum heat transfer amount (Qmax) of the heat pipe can be
effectively increased.
[0042] The conventional wick core structure of the heat pipe is
made by disposing a core rod in the metal pipe to fix the metal
powder and also formed by the high sintering, but the core rod has
a high cost and may be damaged during the process of the sintering
or removing the core rod, and even the wick structure may be also
damaged, so that the performance of the heat pipe is reduced.
However, the wick structure 2e of this embodiment is formed on the
outside firstly, and the form of the wick structure can be designed
according to the performance requirement and won't be limited by
the core rod required for the conventional process. Besides,
favorably, the quality of the wick structure 2e can be examined
outside the pipe 1e firstly to eliminate the defective products in
advance so as to enhance the yield of the heat pipe H5.
[0043] As shown in FIGS. 3A and 3B, in this embodiment, the section
P5 of the wick structure 2e along the axial direction D1 of the
pipe 1e has a discontinuous edge and is not a uniform section
between the two ends E1, E2 of the pipe 1e. In other words, the
section P5 can be divided into the sections P51, P52, P53 from one
end E1 of the pipe 1e to the other end E2, and the section P52 is
located between the sections P51 and P53. Besides, the section P52
has a greater area than the sections P51 and P53. In other words,
the middle region of the heat pipe H5 can be used as the evaporator
of the heat pipe, and in practice, this middle region can be
attached to the heat source so as to achieve a better
heat-dissipation effect.
[0044] In addition to the above-mentioned structure, the
discontinuous edge of the section of the wick structure along the
axial direction also can be applied to the cases of FIGS. 3C and
3D, which are schematic sectional diagrams taken along the line A-A
of the heat pipe of FIG. 3A according to different embodiments of
the invention. The appearance in FIG. 3A with the line A-A is just
for showing the position of the sections in FIGS. 3C and 3D, and
FIGS. 3C and 3D actually show the heat pipe structures of different
embodiments. As shown in FIGS. 3A, 3C, 3D, particularly, the
structures of the heat pipes H6, H7 are substantially the same as
the heat pipe H5 of the above embodiment, wherein each of the
sections P6, P7 of the wick structures 2f, 2g of the heat pipes H6,
H7 along the axial direction D1 of the pipes 1f, 1g is not a
uniform section between the two ends of each of the pipes 1f, 1g,
and besides, the sections of the wick structures 2f, 2g along the
axial direction of the pipes both have a discontinuous edge.
However, the section P6 of the heat pipe H6 has a less area at the
middle region between the two ends E1, E2 of the pipe 1f but has a
greater area at the ends E1, E2; and the section P7 of the heat
pipe H7 has a greater area at the end E1 of the pipe 1g but has a
less area at the end E2. In practice, the region of the section
with a greater area can be attached to the heat source so as to
achieve a better heat-dissipation effect.
[0045] The form of the edge of the section of the wick structure of
the above-mentioned heat pipes H5, H6, H7 is not meant to be
construed in a limiting sense. FIG. 4A is a schematic diagram of
the appearance of the heat pipe of another embodiment of the
invention, and FIGS. 4B, 4C, 4D are schematic sectional diagrams of
the heat pipe in FIG. 4A taken along the line B-B according to
different embodiments. As shown in FIGS. 4A to 4D, in the heat
pipes H8, H9, H10, the sections of the wick structures 2h, 2i, 2j
along the axial directions of the pipes 1h, 1i, 1j all have a
continuous edge. In other words, the edge of each of the sections
of the wick structures 2h, 2i, 2j has a smooth form without the
sectional difference. In comparison with the above embodiments,
since the heat pipes H8, H9, H10 of this embodiment have the
continuous edges, the less flow resistance can be generated and the
maximum thermal design power of the heat pipes H8, H9, H10 can be
thus enhanced.
[0046] Besides, the thickness variation along the axial direction
of the heat pipes H8, H9, H10 is shown as FIG. 4E, which is a
schematic sectional diagram of the heat pipe in FIG. 4A taken along
the line B'-B'. The wick structures 2h, 2i, 2j of the heat pipes
H8, H9, H10 have the thickness variation along the axial direction,
but this thickness variation is not meant to be construed in a
limiting sense and can be adjusted according to the change of the
heat source position.
[0047] In addition to the above embodiments, this invention further
includes the wick structures of other types. FIG. 5A is a schematic
diagram of the appearance of the heat pipe of another embodiment of
the invention, FIGS. 5B and 5D are schematic perspective sectional
diagrams of the heat pipe in FIG. 5A taken along the line C-C
according to different embodiments, and FIGS. 5C and 5E are
schematic sectional diagrams of the heat pipes of FIGS. 5B and 5D
respectively. The appearance in FIG. 5A with the line C-C is just
for showing the position of the sections in FIGS. 5B and 5D, and
FIGS. 5B and 5D actually show the heat pipe structures of different
embodiments. Particularly, like the heat pipe H5 of the above
embodiment, each of the sections of the wick structures 2k, 2m of
the heat pipes H11, H12 along the axial direction D1 of the pipes
1k, 1m is not a uniform section between the two ends of each of the
pipes 1k, 1m. In detail, the wick structures 2k, 2m both have a
varied thickness in the view of the heat pipes H11, H12 along the
radial direction. The thicker region (such as the region R1) can be
used to be attached to the portion of the heat source T having a
higher temperature, and the thinner region (such as the region R2)
can be used to be attached to the portion of the heat source T
having a lower temperature. In other words, the wick structures 2k,
2m of the heat pipes H11, H12 of this embodiment both have the
thickness variation along the redial direction. However, the
distribution and variation of the thickness of the wick structure
is not meant to be construed in a limiting sense, and the wick
structures 2k, 2m can be adjusted according to the space and
performance of the pipes 1k, 1m or the heat-dissipation
requirement. The related application will be illustrated
hereinafter.
[0048] In other embodiments, the embodiments of the heat pipes H8,
H9, H10 also can be combined with the embodiments of the heat pipes
H11, H12. For example, the wick structure of the heat pipe can be
adjusted in both of the axial and radial directions so as to meet
the actual heat-dissipation requirement, but this invention is not
limited thereto.
[0049] FIG. 6A is a schematic diagram of a part of the appearance
of the heat pipe of an embodiment of the invention, and FIG. 6B is
a schematic sectional diagram of the heat pipe in FIG. 6A taken
along the line D-D. As shown in FIGS. 6A and 6B, in comparison with
the above embodiments, the heat pipe H13 includes a larger pipe 1n.
In other words, the pipe 1n includes a larger hollow chamber 10n.
The heat pipe H13 includes a plurality of wick structures 2n
disposed adjacent to each other in the pipe 1n. Through the
disposition of a plurality of wick structures 2n, a flat heat pipe
H13 with a larger area can be formed. Besides, the wick structure
2n of this embodiment further includes at least a support portion
21n (herein for example, each of the wick structures 2n includes a
support portion 21n), and the support portion 21n has the same
material as the wick structure 2n. The support portion 21n presses
the inner wall of the pipe 1n to act as a support structure so as
to prevent the depression and deformation of the heat pipe H13.
[0050] In practice, the above different heat pipe structures can be
combined together to enhance the applicability of the heat pipe. As
shown in FIG. 7 where two heat pipes H11 disposed side by side to
form the heat pipe H14 for the illustrative purpose, when the heat
pipe H14 is viewed in the radial direction, the wick structure 2p
has a varied thickness. The thicker region (such as the region R3)
can act as the evaporator of the heat pipe H14 and the thinner
region (such as the region R4) can act as the condenser of the heat
pipe H14. In detail, the region R3 of the heat pipe H14 can be
disposed closer to the heat source T and the region R4 can be
disposed away from the heat source T. Since the thicker region of
the wick structure 2p has stronger capillarity, the working fluid
will be provided with a better capability of flowing back and the
thicker region can bear larger heat flux and temporary heat impact,
and therefore the heat pipe H14 can operate stably to avoid the
idle heating condition. In practice, a thin metal plate M (such as
a copper plate) can be disposed on the heat source T so as to
evenly disperse the heat of the heat source T and make an evener
heating surface.
[0051] Summarily, the wick structure of the heat pipe of this
invention can be varied in form along the axial direction of the
pipe so as to meet the structure requirement of the evaporator,
heat insulator and condenser of the heat pipe and can be adjusted
according to the space and performance of the pipe of the heat pipe
or according to the actual heat-dissipation requirement.
[0052] The conventional wick core structure of the heat pipe is
made by disposing a core rod in the metal pipe to fix the metal
powder and also formed by the high sintering, but the core rod has
a high cost and may be damaged during the process of the sintering
or removing the core rod, and even the wick structure may be also
damaged, so that the performance of the heat pipe is reduced.
However, the wick structure of this embodiment is formed on the
outside firstly, and the form of the wick structure can be designed
according to the performance requirement and won't be limited by
the core rod required for the conventional process. Besides,
favorably, the quality of the wick structure can be examined
outside the pipe firstly to eliminate the defective products in
advance so as to enhance the yield of the heat pipe.
[0053] Although the invention has been described with reference to
specific embodiments, this description is not meant to be construed
in a limiting sense. Various modifications of the disclosed
embodiments, as well as alternative embodiments, will be apparent
to persons skilled in the art. It is, therefore, contemplated that
the appended claims will cover all modifications that fall within
the true scope of the invention.
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