U.S. patent application number 12/494339 was filed with the patent office on 2010-08-26 for heat pipe and manufacturing method thereof.
This patent application is currently assigned to FURUI PRECISE COMPONENT (KUNSHAN) CO., LTD.. Invention is credited to YI-SHIH HSIEH, YONG-JIAN WANG.
Application Number | 20100212871 12/494339 |
Document ID | / |
Family ID | 42620744 |
Filed Date | 2010-08-26 |
United States Patent
Application |
20100212871 |
Kind Code |
A1 |
HSIEH; YI-SHIH ; et
al. |
August 26, 2010 |
HEAT PIPE AND MANUFACTURING METHOD THEREOF
Abstract
A heat pipe includes a sealed hollow casing, a wick structure
lining an inner surface of the casing and a working medium
contained in an interior of the casing. The casing includes an
elongated main body having an elongated opening extending axially
in the main body and a transparent cover fixed onto the main body
and sealing the opening of the main body. The wick structure is
provided by only lining an inner surface of the main body of the
casing.
Inventors: |
HSIEH; YI-SHIH; (Tu-Cheng,
TW) ; WANG; YONG-JIAN; (Shenzhen City, CN) |
Correspondence
Address: |
PCE INDUSTRY, INC.;ATT. Steven Reiss
288 SOUTH MAYO AVENUE
CITY OF INDUSTRY
CA
91789
US
|
Assignee: |
FURUI PRECISE COMPONENT (KUNSHAN)
CO., LTD.
KunShan City
CN
FOXCONN TECHNOLOGY CO., LTD.
Tu-Cheng
TW
|
Family ID: |
42620744 |
Appl. No.: |
12/494339 |
Filed: |
June 30, 2009 |
Current U.S.
Class: |
165/104.26 ;
29/890.032 |
Current CPC
Class: |
H01L 23/427 20130101;
Y10T 29/49353 20150115; F28D 15/0233 20130101; H01L 2924/0002
20130101; H01L 2924/0002 20130101; H01L 2924/00 20130101; H01L
23/467 20130101; F28F 2220/00 20130101; F28F 2255/00 20130101; F28D
15/046 20130101; F28F 1/24 20130101 |
Class at
Publication: |
165/104.26 ;
29/890.032 |
International
Class: |
F28D 15/04 20060101
F28D015/04; B21D 53/06 20060101 B21D053/06 |
Foreign Application Data
Date |
Code |
Application Number |
Feb 20, 2009 |
CN |
200910300496.3 |
Claims
1. A heat pipe comprising: a sealed hollow casing comprising an
elongated main body having an elongated opening extending axially
in the main body and a transparent cover fixed onto the main body
and sealing the opening of the main body; a wick structure lining
an inner surface of the main body of the casing; and a working
medium contained in an interior of the casing.
2. The heat pipe as described in claim 1, wherein the transparent
cover is made of glass or acryl.
3. The heat pipe as described in claim 1, wherein a cross-section
of the casing is "D" shaped.
4. The heat pipe as described in claim 1, wherein a cross-section
of the main body is "C" shaped, and the transparent cover is
planar.
5. The heat pipe as described in claim 1, wherein an outline of the
opening has two linear portions extending axially and parallel to
each other and two arced portions respectively connected between
two opposite ends of the two linear portions.
6. The heat pipe as described in claim 1, wherein a width of the
opening is smaller than a diameter of the main body of the
casing.
7. A method of manufacturing a heat pipe, comprising: providing a
rudimentary rounded hollow pipe body with a wick structure lining
against an inner surface thereof; cutting a part of the pipe body
along an axial direction of the pipe body out of the pipe body, an
opening being formed on a remaining part of the pipe body;
releasing residual stresses of the remaining part of the pipe body;
providing a transparent cover having a shape corresponding to the
opening of the main body, and affixing the cover to the remaining
part of the pipe body for sealing the opening, cooperatively the
remaining part of the pipe body and the cover forming a casing;
injecting a working medium into the casing; and vacuuming and
hermetically sealing the casing.
8. The heat pipe as described in claim 7, wherein the pipe body is
made of copper or aluminum, and the transparent cover is made of
glass or acryl.
9. The heat pipe as described in claim 7, wherein the part has a
cross-section smaller than a half cross-section of the pipe
body.
10. The heat pipe as described in claim 7, wherein the transparent
cover is plate shaped.
11. The heat pipe as described in claim 10, wherein a cross-section
of the casing is "D" shaped.
Description
BACKGROUND
[0001] 1. Technical Field
[0002] The disclosure relates to heat pipes, and more particularly
to a heat pipe that states of a working medium contained in the
heat pipe is visible and a manufacturing method thereof.
[0003] 2. Description of Related Art
[0004] With continuing development of the electronic technology,
electronic components such as CPUs generate more and more heat that
is required to be dissipated immediately. Heat pipes are commonly
used for cooling the electronic components for their excellent heat
transfer performances.
[0005] Commonly, a heat pipe includes a sealed aluminum or copper
container with an internal surface lined with a capillary wick mesh
and a working medium contained in the container. When used, one end
of the heat pipe is thermally attached to an electronic component
to absorb heat therefrom, and the other end of the heat pipe is
thermally connected to the heat sink. As the heat pipe absorbs heat
at the one end thereof, the working medium is vaporized, and a
pressure gradient is formed in the heat pipe. This pressure
gradient forces the vapor to flow along the heat pipe from the one
end to the other end where the vapor condenses and gives out its
latent heat of vaporization. The working medium is then returned
back to the one end of the heat pipe via the capillary forces
developed in the wick mesh. Thus, the heat generated by the
electronic component can be rapidly transferred to the heat sink
via the heat pipe for further dissipating to ambient air.
[0006] Since the container is made of aluminum or copper, states of
the working medium in the container is not visual observation from
outside of the heat pipe during operation of the heat pipe. The
states of the working medium in the container can only be deduced
by phase change theory, which is not convenient for real-time
observation or real-time monitoring a working process of the heat
pipe. Furthermore, an aging degree of the heat pipe is unable to
judge. After the heat pipe being used a period of time, the heat
pipe usually results in overheat and even in damage of the
electronic component before the users know an excessive aging of
the heat pipe.
[0007] It is thus desirable to provide a heat pipe which can
overcome the described limitations.
BRIEF DESCRIPTION OF THE DRAWINGS
[0008] FIG. 1 is an isometric, assembled view of a heat dissipation
device according to an exemplary embodiment of present
disclosure.
[0009] FIG. 2 is an isometric, assembled view of a heat pipe of the
heat dissipation device of FIG. 1.
[0010] FIGS. 3A-3C are views respectively showing steps of a
manufacturing method of the heat pipe of FIG. 2.
DETAILED DESCRIPTION
[0011] Reference will now be made to the drawing figures to
describe the present heat dissipation device and heat pipe thereof
in detail.
[0012] FIG. 1 illustrates a heat dissipation device in accordance
with an exemplary embodiment of the disclosure. The heat
dissipation device is for dissipating heat generated by an
electronic component 20. The heat dissipation device includes a fin
unit 30, a heat pipe 10 thermally connecting the electronic
component 20 to the fin unit 30, and a centrifugal fan 40 for
providing an airflow flowing through the fin unit 30 to take heat
away.
[0013] Referring to FIG. 2, the heat pipe 10 includes a sealed
hollow casing 11, a wick structure 12 formed on an inner surface of
the casing 11, and a working medium 17 contained in an interior of
the casing 11. The heat pipe 10 includes an evaporating section 13,
an adiabatic section 15 and a condensing section 14 along an axial
direction of the casing 11. The adiabatic section 15 is located
between the evaporating section 13 and the condensing section
14.
[0014] A cross-section of the casing 11 is substantially "D"
shaped. The casing 11 includes an elongated main body 111 having an
elongated opening 110 extending from the evaporating section 13 to
the condensing section 14 and a transparent cover 112 for
hermetically sealing the opening 110 of the main body 111.
[0015] A cross-section of the main body 111 is about "C" shaped.
The main body 111 is made of high thermally conductive material
such as copper or aluminum. The opening 110 is defined in a top
side of the main body 111 and extends along the axial direction of
the main body 111. An outline of the opening 110 includes a first
linear portion 114, a second linear portion 115 parallel to the
first linear portion 114, and first and second arced portions 116,
117 respectively connected between two opposite ends of the first
and second linear portions 114, 115. A length of the opening 110
substantially equals to a length of the main body 111. However, a
width of the opening 110, i.e., a distance between the first and
second linear portions 114, 115, is smaller than a diameter of the
main body 111. The wick structure 12 is only provided lining an
inner surface of the main body 111 of the casing 11. The wick
structure 12 includes a plurality of micro grooves defined in the
inner surface of the main body 111. The micro grooves are evenly
arranged along a circumference direction of the main body 111 of
the casing 11. Each of the micro grooves extends along the axial
direction of the main body 111 from the evaporating section 13 to
the condensing section 14. Alternatively, the wick structure 12 can
be other known type wicks, such as screen mesh, sintering powders,
etc.
[0016] The transparent cover 112 is a rectangular flat plate. The
transparent cover 112 is made of transparent materials such as
acryl, glass or the like. A size of the transparent cover 112 is
slightly larger than that of the opening 110 of the main body 111
for hermetically covering on the opening 110 of the main body 111.
Alternatively, the size of the transparent cover 112 can be equal
to that of the opening 110. The transparent cover 112 and the main
body 111 cooperatively define a sealed space in the interior of the
casing 11 with the wick structure 12 and working medium 17 received
therein.
[0017] The working medium 17 can be water, alcohol or methanol. The
wick structure 12 is saturated with the working medium 17, which
acts as a heat carrier when undergoing phase transitions between
liquid state and vaporous state during operation of the heat pipe
10. The working medium 17 and the wick structure 12 contained in
the interior of the casing 11 are visually observable from the top
side of the heat pipe 10 via the transparent cover 112.
[0018] Referring back to FIG. 1, when assembled, the fin unit 30 is
arranged at an air outlet 42 of the centrifugal fan 40. The fin
unit 30 defines a slot 32 at a middle of a top surface thereof. The
slot 32 has a shape and a size respectively corresponding to a
shape and a size of the main body 111 of the casing 11 of the heat
pipe 10. The condensing section 14 and the adiabatic section 15 of
the heat pipe 10 are receiving in the slot 32, with an outer
surface of the main body 111 at the condensing and adiabatic
sections 14, 15 contacting with the top surface of the fin unit 30
around the slot 32. The transparent cover 112 protrudes out of the
slot 32 of the fin unit 30 and faces a top side of the heat
dissipation device. An outer surface of another end of the main
body 111 corresponding to the evaporation section 13 of the heat
pipe 10 is thermally contacted with a top surface of the electronic
component 20.
[0019] During operation, the main body 111 at the evaporation
section 13 of the heat pipe 10 absorbs heat from the electronic
component 20, the working medium 17 is vaporized to vapor, and a
pressure gradient is formed in the interior of the casing 11. This
pressure gradient forces the vapor to flow along the casing 11 from
the evaporating section 13 to the condensing section 14, where the
vapor condenses back to liquid and gives out its latent heat of
vaporization. The liquid is then returned back to the evaporating
section 13 under a capillary force of the wick structure 12 of the
heat pipe 10. Such a process is repeated so that heat is
continuously transferred from the evaporating section 13 into the
condensing section 14. Thus, the heat generated by the electronic
component 20 is rapidly transferred to the fin unit 30 via the heat
pipe 10 for further dissipating to the ambient air by the airflow
generated by the fan 40.
[0020] Due to the transparent cover 112 formed on the top side of
the casing 111, a phase changing process of the working medium 17
in the interior of casing 111, i.e., the working medium 17
vaporized to vapor at the evaporating section 13 to flow towards
the condensing section 14 along the casing 111, and then condensed
back to liquid at the condensing section 14 to flow back towards
the evaporating section 13 under the capillary force of the wick
structure 12, is visually observable from the top side of the heat
pipe 10. Thus, it is intuitively to know a working principle of the
phase transition of the working medium 17 in the interior of the
casing 111 of the heat pipe 10 and accurately to know a working
process of the heat pipe 10. Therefore, the heat pipe 10 can be
better used in educational training for learners or in researching
and experimenting for researchers. Furthermore, the phase changing
process of the working medium 17 in the interior of the heat pipe
10 can be recorded by a video camera or camcorder from outside of
the heat pipe 10 via the transparent cover 112, which provides more
intellectualized, more convenient, and highly effective learning
for more learners and researchers. Moreover, users can well know a
working performance of the heat pipe 10 by observing speed of the
phase changing process of the working medium 17 via the transparent
cover 112 and easily judge an aging degree of the heat pipe 10
after the heat pipe 10 has been used a period of time. Thus, the
users can easily judge whether the heat pipe 10 needs to be
replaced or repaired to ensure that the electronic component 20 can
always work normally.
[0021] FIGS. 3A-3C respectively show steps for a manufacturing
method of the heat pipe 10. Referring to FIG. 3A, a rudimentary
rounded hollow pipe body 60 with wick structure lining against an
inner surface thereof is provided. The pipe body 60 is made of high
thermally conductive material such as copper or aluminum. A cross
section of the pipe body 60 is annular. One end of the pipe body 60
is enclosed, and the other end of the pipe body 60 is open.
Referring to FIG. 3B, a top part 62 of the pipe body 60 is cut off
from the pipe body 60 along an axial direction of the pipe body 60
via a cutting process. An opening 110 is thus formed on a remaining
part 64 of the pipe body 60 along a cut plane of the pipe body 60.
The remaining part 64 forms the main body 111 of the casing 11 of
the heat pipe 10 of FIG. 2. The top part 62 has an arced
cross-section which is smaller than a half cross-section of the
pipe body 60. Then, residual stresses of the remaining part 64 of
the pipe body 60 caused by the cutting process are released by
stress relief annealing. Referring to FIG. 3C, a transparent cover
112 having a shape corresponding to the opening 110 of the main
body 111 of the casing 11 is provided. The transparent cover 112 is
fixedly affixed to the main body 111 by sealant and thus seals the
opening 110, to thereby form the casing 11 of the heat pipe 10 of
FIG. 2. Subsequently, the working medium 17 such as water, alcohol
or methanol, is injected into the casing 11 via the open end, and
finally, the casing 11 is vacuumed and the open end of the casing
11 is hermetically sealed so as to form the heat pipe 10 with the
transparent cover 112 arranged on the top side thereof as shown in
FIG. 2.
[0022] It is to be understood, however, that even though numerous
characteristics and advantages of the disclosure have been set
forth in the foregoing description, together with details of the
structure and function of the embodiments, the disclosure is
illustrative only, and changes may be made in detail, especially in
matters of shape, size, and arrangement of parts within the
principles of the invention to the full extent indicated by the
broad general meaning of the terms in which the appended claims are
expressed.
* * * * *