U.S. patent application number 14/477879 was filed with the patent office on 2016-03-10 for heat pipe with complex capillary structure.
The applicant listed for this patent is Asia Vital Components Co., Ltd.. Invention is credited to Ching-Hang Shen.
Application Number | 20160069616 14/477879 |
Document ID | / |
Family ID | 55437192 |
Filed Date | 2016-03-10 |
United States Patent
Application |
20160069616 |
Kind Code |
A1 |
Shen; Ching-Hang |
March 10, 2016 |
HEAT PIPE WITH COMPLEX CAPILLARY STRUCTURE
Abstract
A heat pipe with complex capillary structures includes a tubular
body in which a first capillary section and a second capillary
section are disposed. The tubular body has a chamber and a bottom
wall disposed under the chamber. The chamber is sequentially
divided into an evaporation section, a transfer section and a
condensation section. The first capillary section is a knitted mesh
body attached to the bottom wall of the evaporation section of the
tubular body. The second capillary section is a braid body
extending in axial direction of the tubular body from the
evaporation section through the transfer section to the
condensation section. The second capillary section in the
evaporation section is overlapped on the first capillary section.
Accordingly, the heat pipe has an ultrathin structure, while still
able to transfer heat at higher efficiency.
Inventors: |
Shen; Ching-Hang; (New
Taipei City, TW) |
|
Applicant: |
Name |
City |
State |
Country |
Type |
Asia Vital Components Co., Ltd. |
New Taipei City |
|
TW |
|
|
Family ID: |
55437192 |
Appl. No.: |
14/477879 |
Filed: |
September 5, 2014 |
Current U.S.
Class: |
165/104.26 |
Current CPC
Class: |
F28D 15/046 20130101;
F28D 15/0233 20130101 |
International
Class: |
F28D 15/02 20060101
F28D015/02; F28F 13/18 20060101 F28F013/18; F28D 15/04 20060101
F28D015/04 |
Claims
1. A heat pipe with complex capillary structures, comprising: a
tubular body having a chamber and a bottom wall disposed under the
chamber, the chamber being sequentially divided into an evaporation
section, a transfer section and a condensation section, a first
capillary section being attached to the bottom wall of the
evaporation section of the tubular body, the first capillary
section being a knitted mesh body formed of multiple fiber wires
interlaced with each other; and a second capillary section, which
is a braid body formed of multiple strands or bundles of fiber
wires interlaced and tangled with each other, the second capillary
section extending in axial direction of the tubular body from the
evaporation section through the transfer section to the
condensation section.
2. The heat pipe as claimed in claim 1, wherein the second
capillary section in the evaporation section is overlapped on the
first capillary section.
3. The heat pipe as claimed in claim 2, wherein the fiber wires of
the first and second capillary sections are made of metal material
or nonmetal material such as fiber glass or fiber carbon.
4. The heat pipe as claimed in claim 3, wherein the first and
second capillary sections are made of the same material or
different materials.
5. The heat pipe as claimed in claim 3, wherein the density of the
first capillary section is smaller than or larger than the density
of the second capillary section.
6. The heat pipe as claimed in claim 1, wherein the evaporation
section has an inner surface on an inner side of the bottom wall
and an outer surface on an outer side of the bottom wall, the outer
surface being removably in contact with a heat generation
component.
7. The heat pipe as claimed in claim 6, wherein the second
capillary section is positioned at the center of the chamber.
8. The heat pipe as claimed in claim 6, wherein the second
capillary section is positioned on one side of the chamber.
9. The heat pipe as claimed in claim 8, further comprising another
second capillary section positioned on the other side of the
chamber.
10. The heat pipe as claimed in claim 6, wherein the first
capillary section is attached to and coated on the inner surface of
the evaporation section.
11. The heat pipe as claimed in claim 10, wherein the tubular body
has two sidewalls, the first capillary section having a left side
and a right side in adjacency to the two sidewalls of the tubular
body respectively, the left and right sides defining a first
width.
12. The heat pipe as claimed in claim 11, wherein the second
capillary section has a left side and a right side, the left and
right sides defining a second width, the second width being smaller
than the first width.
13. The heat pipe as claimed in claim 2, wherein at least one face
of the tubular body in adjacency to the chamber is a free face.
Description
BACKGROUND OF THE INVENTION
[0001] 1. Field of the Invention
[0002] The present invention relates generally to a heat pipe with
capillary structures, and more particularly to a heat pipe with
complex capillary structures composed of different capillary
structures.
[0003] 2. Description of the Related Art
[0004] There is a trend to miniaturize various electronic and
electrical apparatuses such as computers and intelligent electronic
apparatuses. Therefore, these apparatuses have become thinner and
thinner. Also, the performances of these apparatuses have become
higher and higher. This means that the internal heat transfer
components and heat dissipation components of these apparatuses
must be miniaturized and thinned in adaptation to the miniaturized
apparatuses to meet the requirements of consumers.
[0005] A heat pipe is a heat conduction component with excellent
heat conductivity. The heat pipe has heat conductivity several
times to several tens times that of copper, aluminum or the like.
Therefore, the heat pipe serves as a cooling component applied to
various electronic apparatuses.
[0006] There are many manufacturing methods for the conventional
heat pipe structures. For example, in a conventional manufacturing
method of the heat pipe, metal powder is filled into a hollow
tubular body. Then the metal powder is sintered to form a capillary
structure layer on the inner wall face of the tubular body. Then
the tubular body is vacuumed and filled with the working fluid and
then sealed. Alternatively, a metal-made mesh body is placed into a
tubular body. The mesh capillary structure body will naturally
stretch and outward extend to attach to the inner wall face of the
tubular body to form a capillary structure layer. Then the tubular
body is vacuumed and filled with the working fluid and then sealed.
On the demand of the electronic equipment for slim configuration,
the heat pipe must be made with the form of a flat plate.
[0007] The flat-plate heat pipe has a thinned structure. However,
such flat-plate heat pipe has a shortcoming. That is, in the
conventional flat-plate heat pipe, the metal powder is sintered to
form a capillary structure layer on the inner wall face of the
tubular body. The sintered body is fully coated on the inner wall
face of the tubular body. When the tubular body is compressed and
flattened, the capillary structures, (that is, the sintered metal
powder or the mesh capillary structure body) on two sides of the
compressed face in the flat-plate heat pipe are likely to damage
due to compression. After damaged, the capillary structures will
detach from the inner wall face of the flat-plate heat pipe. In
this case, the heat transfer performance of the flat-plate heat
pipe will be greatly deteriorated or even the flat-plate heat pipe
will be disabled. Moreover, the thin flat-plate heat pipe is
applied to an intelligent mobile phone, a tablet or an ultrathin
notebook computer. However, the capillary structures such as the
sintered metal powder or the mesh capillary structure body or the
channeled structure is fully coated on the wall face of the
flat-plate heat pipe. As a result, the thickness of the wall of the
flat-plate heat pipe plus the thickness of the capillary structures
fully coated on the wall face of the flat-plate heat pipe will lead
to a considerable total thickness of the flat-plate heat pipe.
Under such circumstance, the heat pipe can be hardly truly thinned
and applied to the intelligent mobile phone, the tablet and the
ultrathin notebook computer or other portable electronic
apparatuses.
SUMMARY OF THE INVENTION
[0008] It is therefore a primary object of the present invention to
provide a heat pipe with complex capillary structures. A capillary
structure is disposed in the tubular body of the heat pipe in the
longitudinal direction to provide axial transfer effect. Another
large-area capillary structure is disposed on the bottom of one end
of the tubular body to provide radial transfer effect.
[0009] It is a further object of the present invention to provide
the above heat pipe in which a first capillary structure coated on
an inner face of the evaporation section opposite to the outer
heated face of the evaporation section. In addition, a second
capillary structure extends from the evaporation section to the
condensation section and is overlapped on and connected with the
first capillary structure. Accordingly, the working fluid can
axially flow from the condensation section along the second
capillary structure back to the evaporation section. Then the
working fluid can be radially spread along the first capillary
structure to the entire inner surface of the evaporation section.
Therefore, on the demand of the electronic apparatus for extremely
thinned structure, the heat pipe of the present invention has an
ultrathin structure, while still able to bear the high heat of the
heat source to transfer the heat at higher efficiency.
[0010] To achieve the above and other objects, the heat pipe with
complex capillary structures of the present invention includes a
tubular body having a chamber and a bottom wall disposed under the
chamber. The chamber is sequentially divided into an evaporation
section, a transfer section and a condensation section. A first
capillary section is attached to the bottom wall of the evaporation
section of the tubular body. The first capillary section is a
knitted mesh body formed of multiple fiber wires interlaced with
each other. The heat pipe further includes a second capillary
section, which is a braid body formed of multiple strands or
bundles of fiber wires interlaced and tangled with each other. The
second capillary section extends in axial direction of the tubular
body from the evaporation section through the transfer section to
the condensation section.
[0011] In the above heat pipe, the second capillary section in the
evaporation section is overlapped on the first capillary
section.
[0012] In the above heat pipe, the fiber wires of the first and
second capillary sections are made of metal material or nonmetal
material such as fiber glass or fiber carbon.
[0013] In the above heat pipe, the first and second capillary
sections are made of the same material or different materials.
[0014] In the above heat pipe, the density of the first capillary
section is smaller than or larger than the density of the second
capillary section.
[0015] In the above heat pipe, the evaporation section has an inner
surface on an inner side of the bottom wall and an outer surface on
an outer side of the bottom wall, the outer surface being removably
in contact with a heat generation component.
[0016] In the above heat pipe, the second capillary section is
positioned at the center of the chamber.
[0017] In the above heat pipe, the second capillary section is
positioned on one side of the chamber.
[0018] The above heat pipe further includes another second
capillary section positioned on the other side of the chamber.
[0019] In the above heat pipe, the first capillary section is
attached to and coated on the inner surface of the evaporation
section.
[0020] In the above heat pipe, the first capillary section has a
left side and a right side in adjacency to two sidewalls of the
tubular body respectively. The left and right sides define a first
width.
[0021] In the above heat pipe, the second capillary section has a
left side and a right side. The left and right sides define a
second width. The second width is smaller than the first width.
[0022] In the above heat pipe, at least one face of the tubular
body in adjacency to the chamber is a free face.
BRIEF DESCRIPTION OF THE DRAWINGS
[0023] The structure and the technical means adopted by the present
invention to achieve the above and other objects can be best
understood by referring to the following detailed description of
the preferred embodiments and the accompanying drawings,
wherein:
[0024] FIG. 1 is a top view of the heat pipe of the present
invention;
[0025] FIG. 2 is a sectional view taken along line A-A' of FIG. 1,
showing the evaporation section of the heat pipe of the present
invention;
[0026] FIG. 3 is a sectional view showing the first and second
capillary structures of the present invention;
[0027] FIG. 4 is a sectional view taken along line B-B' of FIG. 1,
showing the condensation section of the heat pipe of the present
invention;
[0028] FIG. 5 is a sectional view showing that the second capillary
section of the present invention is positioned in the chamber of
the tubular body in another position; and
[0029] FIG. 6 is a sectional view showing that the second capillary
section of the present invention is positioned in the chamber of
the tubular body in still another position.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
[0030] The embodiments of the present invention will be described
hereinafter with reference to the drawings, wherein the same
components are denoted with the same reference numerals.
[0031] Please refer to FIGS. 1 to 3. FIG. 1 is a top view of the
heat pipe of the present invention. FIG. 2 is a sectional view
taken along line A-A' of FIG. 1, showing the evaporation section of
the heat pipe of the present invention. FIG. 3 is a sectional view
showing the first and second capillary structures of the present
invention. According to the drawings, the heat pipe 10 of the
present invention includes a tubular body 11 having an evaporation
section 101, a transfer section 102 and a condensation section 103.
The evaporation section 101 and the condensation section 103 are
positioned at two ends of the tubular body 11. The transfer section
102 is positioned in the middle of the tubular body 11 in
communication with the evaporation section 101 and the condensation
section 103. In this embodiment, the heat pipe 10 is, but not
limited to, an elongated body. Alternatively, the heat pipe 10 can
be an L-shaped or U-shaped body according to the use
requirement.
[0032] Referring to FIGS. 2 and 3 as well as FIG. 1, the tubular
body 11 has a top wall 111, a bottom wall 112 and two sidewalls
113, 114. The top wall 111 is oppositely spaced from the bottom
wall 112. The two sidewalls 113, 114 are positioned between the top
wall 111 and the bottom wall 112. The top wall 111, the bottom wall
112 and the two sidewalls 113, 114 together define a chamber 115.
The chamber 115 is sequentially divided into the evaporation
section 101, the transfer section 102 and the condensation section
103. A working fluid (not shown) is contained in the chamber 115.
For example, the working fluid is, but not limited to, pure water,
inorganic compound, alcohol group, ketone group, liquid metal,
coolant, organic compound or a mixture thereof. The evaporation
section 101 has an inner surface 1011 on an inner side of the
bottom wall 112 in adjacency to the chamber 115 and an outer
surface 1012 on an outer side of the bottom wall 112 opposite to
the inner surface 1011. The outer surface 1012 is removably in
contact with a heat generation component (such as a CPU). The heat
generated by the heat generation component can be transferred
through the bottom wall 112 into the chamber 115 of the evaporation
section 101.
[0033] A first capillary section 12 and a second capillary section
13 are disposed in the chamber 115. When the working fluid in the
chamber 115 of the evaporation section 101 is heated to change into
vapor, the vapor passes through the transfer section 102 to the
condensation section 103 to be cooled into liquid. Then, by means
of the capillary attraction of the first and second capillary
sections 12, 13, the liquid flows back to the evaporation section
101. Accordingly, the liquid-vapor phase change of the working
fluid is circulated between the evaporation section 101 and the
condensation section 103 to achieve convection effect and the
object of heat transfer.
[0034] It should be noted that in order to extremely thin the heat
pipe, at least one face of the tubular body 11 in adjacency to the
chamber is a free face. The first capillary section 12 is only
attached to the bottom wall 112 of the evaporation section 101 of
the tubular body 11. That is, the first capillary section 12 is
only attached to and coated on the inner surface 1011 of the
evaporation section 101. Therefore, the inner surfaces of the top
wall 111 and the two sidewalls 113, 114 of the evaporation section
101 in adjacency to the chamber 115 are free faces. In addition,
the inner surfaces of the top wall 111 and the two sidewalls 113,
114 of the transfer section 102 and the condensation section 103 in
adjacency to the chamber 115 are also free faces without any
characteristic or structure such as channeled structure or sintered
texture. The first capillary section 12 has a right side 122 and a
left side 121 near the two sidewalls 113, 114 of the tubular body
11 respectively. The left and right sides 121, 122 define a first
width b1. The first capillary section 12 is a knitted mesh body
formed of multiple fiber wires interlaced with each other. In this
embodiment, the first capillary section 12 is a mesh body formed of
longitudinal and latitudinal fiber wires interlaced with each
other. The first capillary section 12 has excellent radial
capillary attraction.
[0035] The second capillary section 13 is disposed in an axial
(longitudinal) direction of the tubular body 11. That is, the
second capillary section 13 extends from the evaporation section
101 through the transfer section 102 to the condensation section
103. In the evaporation section 101, the second capillary section
13 is overlapped on the first capillary section 12. The overlapping
sections of the first and second capillary sections 12, 13 are
tightly mated with each other to ensure that the capillary transfer
path is continued without interruption. The second capillary
section 13 has a left side 131 and a right side 132. The left and
right sides 131, 132 define a second width b2 smaller than the
first width b1 of the first capillary section 12. In this
embodiment, the second capillary section 13 is positioned at the
center of the chamber 115. Therefore, the spaces of the chamber 115
are positioned between upper side of the second capillary section
13 and the top wall 111 and between the left and right sides 131,
132 of the second capillary section 13 and the two sidewalls 113,
114 of the tubular body. These spaces form the flow passage of the
working fluid. The second capillary section 13 is a braid body
formed of multiple strands or bundles of fiber wires interlaced and
tangled with each other. Accordingly, the second capillary section
13 is a solid capillary structure with excellent axial capillary
attraction.
[0036] Especially, the fiber wires of the first and second
capillary sections 12, 13 are made of metal material or nonmetal
material such as fiber glass or fiber carbon. In a preferred
embodiment, the first and second capillary sections 12, 13 are made
of the same material. In another preferred embodiment, the first
and second capillary sections 12, 13 are made of different
materials. In addition, the diameters of the fiber wires of the
first and second capillary sections 12, 13 can be equal or unequal
to each other.
[0037] It should be noted that the density of the first and second
capillary sections 12, 13 can be adjusted as necessary. The density
of the first capillary section 12 can be larger than, smaller than
or equal to the density of the second capillary section 13. In the
case that the density of the first capillary section 12 is larger
than or smaller than the density of the second capillary section
13, the capillary transfer forces of the first and second capillary
sections 12, 13 for the working fluid in the chamber are different.
In the case that the density of the first capillary section 12 is
equal to the density of the second capillary section 13, the
capillary transfer forces of the first and second capillary
sections 12, 13 for the working fluid are equal to each other.
[0038] FIG. 4 is a sectional view taken along line B-B' of FIG. 1,
showing the condensation section of the heat pipe of the present
invention. Also referring to FIG. 1, the second capillary structure
13 is disposed on the inner face of the bottom wall 112 in
adjacency to the chamber 115 and extends through the transfer
section 102 of the tubular body 11 to the condensation section
103.
[0039] When the working fluid in the evaporation section 101 is
heated and evaporated into vapor, the vapor with the heat passes
through the transfer section 102 to the condensation section 103 to
be cooled into liquid. Then, via the axially arranged second
capillary section 13, the liquid quickly flows back to the
evaporation section 101. Then, via the first capillary section 12,
the working fluid is radially spread to the entire inner surface
1011 of the evaporation section 101.
[0040] Please now refer to FIGS. 5 and 6. FIG. 5 is a sectional
view showing that the second capillary section of the present
invention is positioned in the chamber of the tubular body in
another position. FIG. 6 is a sectional view showing that the
second capillary section of the present invention is positioned in
the chamber of the tubular body in still another position. As shown
in FIG. 5, in another embodiment, the second capillary section 13
can be alternatively disposed on one side of the chamber 115, such
as the right side of the chamber 115 in adjacency to the sidewall
113 of the tubular body 11. Alternatively, as shown in FIG. 6, two
second capillary sections 13a, 13b are disposed on two sides of the
chamber 115, such as the left and right sides of the chamber 115 in
adjacency to the sidewalls 113, 114 of the tubular body 11
respectively.
[0041] In conclusion, on the demand of the electronic apparatus for
extremely thinned structure, the heat pipe of the present invention
has an ultrathin structure, while still able to bear the high heat
of the heat source to transfer the heat at higher efficiency.
Therefore, the heat pipe of the present invention is applicable to
various electronic apparatuses and handheld apparatuses such as
mobile phones, tablets, PDA, digital displays and ultrathin
notebook computers to effectively solve the heat dissipation
problem of these apparatuses.
[0042] The present invention has been described with the above
embodiments thereof and it is understood that many changes and
modifications in the above embodiments can be carried out without
departing from the scope and the spirit of the invention that is
intended to be limited only by the appended claims.
* * * * *