U.S. patent application number 12/620571 was filed with the patent office on 2011-03-03 for heat dissipation device.
This patent application is currently assigned to FU ZHUN PRECISION INDUSTRY (SHEN ZHEN) CO., LTD.. Invention is credited to JER-HAUR KUO, FANG-XIANG YU.
Application Number | 20110048682 12/620571 |
Document ID | / |
Family ID | 43623109 |
Filed Date | 2011-03-03 |
United States Patent
Application |
20110048682 |
Kind Code |
A1 |
YU; FANG-XIANG ; et
al. |
March 3, 2011 |
HEAT DISSIPATION DEVICE
Abstract
A heat dissipation device includes a heat pipe and a heat sink.
The heat sink defines a through hole with a diameter slightly
smaller then an outer diameter of the heat pipe. The heat pipe is
fixedly engaging in the through hole of the heat sink via
interference fit. The heat pipe includes a tube defining an
interspace therein, a first wick formed on an inner surface of the
tube, working fluid received in the interspace of the tube, and a
retaining structure. The retaining structure is received in the
interspace of the tube and abuts the first wick of the tube to
enhance a rigidity of the tube. A second wick is formed on an outer
surface of the retaining structure and connects with the first wick
of the tube.
Inventors: |
YU; FANG-XIANG; (Shenzhen
City, CN) ; KUO; JER-HAUR; (Tu-Cheng, TW) |
Assignee: |
FU ZHUN PRECISION INDUSTRY (SHEN
ZHEN) CO., LTD.
Shenzhen City
CN
FOXCONN TECHNOLOGY CO., LTD.
Tu-Cheng
TW
|
Family ID: |
43623109 |
Appl. No.: |
12/620571 |
Filed: |
November 17, 2009 |
Current U.S.
Class: |
165/104.26 ;
165/185 |
Current CPC
Class: |
G06F 1/20 20130101; F28D
15/0283 20130101; F28D 15/046 20130101; H01L 23/427 20130101; F28F
1/14 20130101; H01L 2924/0002 20130101; H01L 2924/0002 20130101;
H01L 2924/00 20130101 |
Class at
Publication: |
165/104.26 ;
165/185 |
International
Class: |
F28D 15/04 20060101
F28D015/04; F28F 7/00 20060101 F28F007/00 |
Foreign Application Data
Date |
Code |
Application Number |
Aug 31, 2009 |
CN |
200910306391.9 |
Claims
1. A heat dissipation device, comprising: a heat sink defining a
through hole therein; and a heat pipe having an outer diameter
slightly larger than a diameter of the through hole of the heat
sink and being fixedly engaging in the through hole via
interference fit, the heat pipe comprising a tube defining an
interspace therein, a first wick formed on an inner surface of the
tube, working fluid received in the interspace of the tube, and a
retaining structure received in the interspace of the tube and
abutting the first wick on the tube to enhance a rigidity of the
tube, and a second wick being formed on an outer surface of the
retaining structure.
2. The heat dissipation device of claim 1, wherein the heat sink
comprises a main body and a plurality of dissipation fins, the main
body being a quadrangular prism, the through hole being defined in
a center of the main body, the plurality of dissipation fins
extending generally away from a middle of the main body.
3. The heat dissipation device of claim 2, wherein four ribs
respectively extend from four corners of the main body, the
dissipation fins at each lateral side of the main body are
perpendicular to that lateral side of the main body and are located
between two corresponding neighboring ribs, and outer ends of the
dissipation fins at each lateral side of the main body and outer
ends of the two corresponding neighboring ribs are coplanar.
4. The heat dissipation device of claim 1, wherein the retaining
structure comprises two plates perpendicularly crossing each other,
lateral edges of each plate abutting the first wick, the interspace
of the tube being separated into four axial channels by the
retaining structure, and the second wick being formed on an outer
surface of each plate.
5. The heat dissipation device of claim 1, wherein the retaining
structure comprises four plates, one of the four plates
perpendicularly crossing the other three plates, lateral edges of
each plate abutting the first wick, the interspace of the tube
thereby being separated into eight axial channels by the retaining
structure, the second wick being formed on an outer surface of each
plate.
6. The heat dissipation device of claim 1, wherein the retaining
structure comprises a hollow core and a plurality of supporting
fins extending from an outer circumferential surface of the core,
lateral edges of each of the supporting fins abutting the first
wick, the second wick being formed on an outer surface of each
supporting fin and the outer circumferential surface of the
core.
7. The heat dissipation device of claim 6, wherein the core has a
uniform outer diameter smaller than an inner diameter of the tube,
each supporting fin being rectangular, a third wick being arranged
in the core for providing a path for condensed working fluid to
flow back to a vaporizing region of the interspace, and a channel
being defined between each two neighboring supporting fins for
moving of vaporized working fluid.
8. The heat dissipation device of claim 6, wherein the core has an
outer diameter gradually decreasing from bottom to top, a maximum
outer diameter of the core being substantially equal to an inner
diameter of the tube, each supporting fin being triangular, a
channel being defined inside the core for moving of vaporized
working fluid.
9. The heat dissipation device of claim 6, wherein the core
comprises an upper portion and a lower portion, the lower portion
having an outer diameter gradually decreasing from bottom to top,
the upper portion having a uniform outer diameter being not larger
than a minimum outer diameter of the lower portion, a maximum outer
diameter of the lower portion being approximately the same as an
inner diameter of the tube, a channel being defined in the core for
moving of vaporized working fluid, each supporting fin comprising
an upper section being rectangular and a lower section being
triangular.
10. The heat dissipation device of claim 9, wherein the outer
diameter of the upper portion of the core is smaller than the
minimum diameter of the lower portion of the core, a generally
annular step being formed at a top of the lower portion of the
core, the step adjoining an outer periphery of a bottom of the
upper portion of the core.
11. The heat dissipation device of claim 1, wherein the tube of the
heat pipe is open at two opposite ends thereof, two caps being
fixed onto the two opposite ends of the tube to seal the tube, the
retaining structure having a length in an axial direction smaller
than that of the tube, the retaining structure attaching to one of
the two caps and spaced a distance from the other one of the two
caps, a third wick being formed on the one of the two caps and
connecting with the first wick and the second wick.
12. A heat pipe comprising: a tube defining an interspace therein;
a first wick formed on an inner surface of the tube; working fluid
received in the interspace of the tube; and a retaining structure
received in the interspace of the tube and abutting the first wick
of the tube to enhance a rigidity of the tube, and a second wick
being formed on an outer surface of the retaining structure and
connecting with the first wick of the tube.
13. The heat dissipation device of claim 12, wherein the retaining
structure comprises two plates perpendicularly crossing each other,
lateral edges of each plate abutting the first wick, the interspace
of the tube being separated into four axial channels by the
retaining structure, and the second wick being formed on an outer
surface of each plate.
14. The heat dissipation device of claim 12, wherein the retaining
structure comprises four plates, one of the four plates
perpendicularly crossing the other three plates, lateral edges of
each plate abutting the first wick, the interspace of the tube
thereby being separated into eight axial channels by the retaining
structure, the second wick being formed on an outer surface of each
plate.
15. The heat dissipation device of claim 12, wherein the retaining
structure comprises a hollow core and a plurality of supporting
fins extending from an outer circumferential surface of the core,
lateral edges of each of the supporting fins abutting the first
wick, the second wick being formed on an outer surface of each
supporting fin and the outer circumferential surface of the
core.
16. The heat dissipation device of claim 15, wherein the core has a
uniform outer diameter smaller than an inner diameter of the tube,
each supporting fin being rectangular, a third wick being arranged
in the core for providing a path for condensed working fluid to
flow back to a vaporizing region of the interspace, and a channel
being defined between each two neighboring supporting fins for
moving of vaporized working fluid.
17. The heat dissipation device of claim 15, wherein the core has
an outer diameter gradually decreasing from bottom to top, a
maximum outer diameter of the core being substantially equal to an
inner diameter of the tube, each supporting fin being triangular, a
channel being defined inside the hollow core for moving of
vaporized working fluid.
18. The heat dissipation device of claim 15, wherein the core
comprises an upper portion and a lower portion, the lower portion
having an outer diameter gradually decreasing from bottom to top,
the upper portion having a uniform outer diameter being not larger
than a minimum outer diameter of the lower portion, a maximum outer
diameter of the lower portion being approximately the same as an
inner diameter of the tube, a channel being defined in the core for
moving of vaporized working fluid, each supporting fin comprising
an upper section being rectangular and a lower section being
triangular.
19. The heat dissipation device of claim 18, wherein the outer
diameter of the upper portion of the core is smaller than the
minimum diameter of the lower portion of the core, a generally
annular step being formed at a top of the lower portion of the
core, the step adjoining and an outer periphery of a bottom of the
upper portion of the core.
20. The heat dissipation device of claim 12, wherein the tube of
the heat pipe is open at two opposite end thereof, two caps being
fixed onto the two opposite ends of the tube to seal the tube, the
retaining structure having a length in an axial direction smaller
than that of the tube, the retaining structure attaching to one of
the two caps and spaced a distance from the other one of the two
caps, a third wick being formed on the one of the two caps and
connecting with the first wick and the second wick.
Description
BACKGROUND
[0001] 1. Technical Field
[0002] The disclosure generally relates to heat dissipation
devices, and more particularly to a heat dissipation device
incorporating an improved heat pipe.
[0003] 2. Description of Related Art
[0004] With the continuing development of electronics technology,
electronic components such as central processing units (CPUs) used
in computers are generating more and more heat which is required to
be dissipated immediately. A heat dissipation device is usually
adopted for cooling the electronic component.
[0005] Typically, a heat dissipation device includes a heat pipe
and a fin-type heat sink. The heat pipe includes a sealed tube, a
wick structure attaching to an inner surface of the tube, and
working fluid received in the tube. One end of the heat pipe forms
an evaporation end and attaches to an electronic component to
absorb heat therefrom, and an opposite end of the heat pipe forms a
condensation end and extends through the heat sink to transfer the
heat of the electronic component to the heat sink for further
dissipation. Usually, the condensation end of the heat pipe is
inserted into the heat sink by way of interference fit, therefore
the condensing end of the heat pipe can be maintained in intimate
contact with the heat sink. Thus the heat of the electronic
component can be timely transferred from the condensation end of
the heat pipe to the heat sink.
[0006] However, in many cases, the tube of the heat pipe may deform
during assembly of the heat pipe into the heat sink, and thus the
wick structure attached on the tube may be damaged or destroyed.
For example, narrow gaps are usually formed between the tube and
the wick structure. It is well known that, in the heat pipe, the
wick structure not only provides a capillary force for drawing
condensed working fluid from the condensation end back to the
evaporation end, but also provides a heat transfer path between the
tube and the working fluid contained in the tube. Therefore, if the
wick structure is damaged or destroyed, a heat transfer capability
of the heat pipe may be greatly impaired. Accordingly, a heat
dissipation efficiency of the heat dissipation device is
reduced.
[0007] For the foregoing reasons, therefore, there is a need in the
art for a heat dissipation device incorporating a heat pipe which
can overcome the limitations described.
BRIEF DESCRIPTION OF THE DRAWINGS
[0008] FIG. 1 is an assembled, isometric view of a heat dissipation
device in accordance with a first embodiment.
[0009] FIG. 2 is an exploded view of a heat pipe of the heat
dissipation device of FIG. 1.
[0010] FIG. 3 is an assembled view of the heat pipe of FIG. 2, but
with two end caps thereof being omitted.
[0011] FIG. 4 is a schematic view of a wick structure of a heat
pipe according to a second embodiment.
[0012] FIG. 5 shows a wick structure according to a third
embodiment.
[0013] FIG. 6 shows a wick structure according to a fourth
embodiment.
[0014] FIG. 7 shows a wick structure according to a fifth
embodiment.
DETAILED DESCRIPTION
[0015] Referring to FIG. 1, a heat dissipation device according to
a first embodiment includes a heat sink 10 and a heat pipe 20.
[0016] The heat sink 10 overall has a substantially rectangular
configuration. The heat sink 10 includes a main body 12, and a
plurality of dissipation fins 14 extending outwardly generally away
from a middle of the heat sink 10. The main body 12 is a
quadrangular prism, and defines an approximately rectangular top
surface, an opposite rectangular bottom surface, and four
rectangular side surfaces between the top surface and the bottom
surface. A through hole 124 extends through the main body 12 along
an axial direction of the main body 12 from the bottom surface to
the top surface of the main body 12. The through hole 124 is
substantially located at a center of the main body 12. A cross
section of the through hole 124 is circular.
[0017] Four ribs 16 extend outwardly from four corners of the main
body 12, respectively, i.e., from junctions of the four side
surfaces of the main body 12. The dissipation fins 14 are formed at
all four lateral sides of the main body 12. Each dissipation fin 14
is plate-shaped. The dissipation fins 14 at each lateral side of
the main body 12 are located between two neighboring ribs 16, and
have outer ends coplanar with outer ends of the two neighboring
ribs 16. The dissipation fins 14 at left and right lateral sides of
the main body 12 are parallel to each other, while perpendicular to
the left and the right lateral sides of the heat sink 10. The
dissipation fins 14 at front and rear lateral sides of the main
body 12 are parallel to each other, while perpendicular to the
front and rear lateral sides of the heat sink 10. Thus, the
dissipation fins 14 at the left and right lateral sides of the main
body 12 are perpendicular to the dissipation fins 14 at the front
and rear lateral sides of the main body 12.
[0018] In this embodiment, the heat pipe 20 is a round-type heat
pipe 20, and has an outer diameter slightly larger than a diameter
of the through hole 124 of the main body 12 of the heat sink 10.
Referring also to FIGS. 2 and 3, the heat pipe 20 includes a tube
26, a bottom cap 22, a top cap 24, working fluid (not shown), and a
retaining structure 28. The tube 26, the bottom cap 22 and the top
cap 24 cooperatively form a sealed interspace 268 in the heat pipe
20, the sealed interspace 268 receiving the working fluid and the
retaining structure 28 therein.
[0019] The tube 26 is cylindrical. An outer diameter of the tube 26
is slightly larger than the diameter of the through hole 124 of the
main body 12 of the heat sink 10. A first wick 260 is provided on
an entire inner surface of the tube 26, in the form of a layer. The
first wick 260 is for providing a capillary force to draw back
condensed working fluid. Both of the bottom cap 22 and the top cap
24 are disk-shaped. A diameter of each of the bottom cap 22 and the
top cap 24 is equal to the outer diameter of the tube 26. The
bottom cap 22 and the top cap 24 respectively couple to a bottom
end 262 and a top end 264 of the tube 26, thereby forming the
interspace 268. The bottom cap 22 has a planar-shaped bottom
surface 222 and an opposite top surface. A third wick 220 is
provided on the top surface of the bottom cap 22, in the form of a
layer. The top cap 24 has a top surface 240 and an opposite bottom
surface. An annular protrusion 242 extends upwardly from a center
of the top surface 240 of the top cap 24. An aperture (not shown)
extends through the top cap 24 and communicates with the protrusion
242.
[0020] In this embodiment, the retaining structure 28 includes two
plates 282, 284. The two plates 282, 284 are substantially the same
as each other. Each of the plates 282, 284 is elongated,
rectangular and thin. A width of each plate 282, 284 is
substantially the same as an inner diameter of the tube 26, and a
length of each plate 282, 284 is a little shorter than a length of
the tube 26 in an axial direction of the tube 26. The two plates
282, 284 perpendicularly cross each other, and thus the retaining
structure 28 has a profile like a cross. A second wick 280 is
formed on an outer surface of each plate 282, 284, in the form of a
layer. In this embodiment, the first wick 260 of the tube 26, the
third wick 220 of the bottom cap 22, and the second wick 280 of the
retaining structure 28 are sintered powder. Alternatively, the
wicks 260, 220, 280 of the tube 26, the bottom cap 22, and the
retaining structure 28 can be screen mesh or fine grooves. The
wicks 260, 220, 280 of the tube 26, the bottom cap 22, and the
retaining structure 28 can all be of the same type, or can be of
different types.
[0021] When the heat dissipation device is assembled, the retaining
structure 28 is arranged in the tube 26 with a bottom end thereof
being at the same level as the bottom end 262 of the tube 26. Since
the width of each plate 282, 284 of the retaining structure 28 is
approximately the same as the inner diameter of the tube 26, each
of the two plates 282, 284 abuts the first wick 260 of the tube 26
at opposite two lateral edges thereof. Accordingly, the second wick
280 on the retaining structure 28 is connected to the first wick
260 of the tube 26. The bottom cap 22 is coupled to the bottom end
262 of the tube 26 and is fixed onto the tube 26 by soldering. The
third wick 220 on the bottom cap 22 is thus connected to the first
wick 260 of the tube 26 and the second wick 280 of the retaining
structure 28. Similarly, the top cap 24 is coupled and fixed onto
the top end 264 of the tube 26 by soldering. Since the retaining
structure 28 is shorter than the tube 26, the top cap 24 spaces a
distance from a top end of the retaining structure 28.
[0022] Then working fluid is injected into the tube 26 via the
protrusion 242 and the aperture of the top cap 24. Finally, air is
evacuated from the tube 26, and the protrusion 242 is sealed to
form the heat pipe 20. The sealed interspace 268 formed in the heat
pipe 20 between the top cap 24, the bottom cap 22 and the tube 26
is separated into four channels 266 by the two plates 282, 284 of
the retaining structure 28 received in the interspace 268. In this
embodiment, the four channels 266 are the same as each other. Each
of the channels 266 extends along the axial direction of the tube
26, and communicates the other channels 266 over the top end of the
retaining structure 28.
[0023] When assembling the heat pipe 20 to the heat sink 10, the
heat pipe 20 is vertically inserted into the through hole 124 of
the heat sink 10 until the bottom surface of the bottom cap 22 of
the heat pipe 20 is at the same level as the bottom surface of the
heat sink 10. Since the heat pipe 20 has the retaining structure 28
arranged therein, a rigidity of the tube 26 of the heat pipe 20 is
enhanced. That is, the tube 26 of the heat pipe 20 resists
deformation during assembly even though the outer diameter of the
heat pipe 20 is slightly larger than the diameter of the through
hole 124 of the heat sink 10. Thus damage to or destruction of the
first wick 260 of the tube 26 of the heat pipe 20 is avoided.
[0024] During operation of the heat dissipation device, the bottom
surface of the bottom cap 22 of the heat pipe 20 attaches to an
electronic component tightly to absorb heat therefrom, and thereby
rapidly transfers the heat to the working fluid in the heat pipe
20. The working fluid vaporizes immediately and flows upwardly
along the channels 266 to dissipate the heat to the heat sink 10.
Since the first wick 260 on the tube 26 of the heat pipe 20 is
intact and fully functional, the first wick 260 not only can
provide a capillary force for drawing condensed working fluid back
to a bottom of the heat pipe 20, but also can provide a heat
transfer path between the tube 26 and the working fluid. In
addition, the second wick 280 on the retaining structure 28 also
can provide a capillary force for drawing back condensed working
fluid. Therefore, the heat of the electronic component can be
timely transferred to the heat sink 10 by the heat pipe 20.
[0025] FIG. 4 shows a retaining structure 28a according to a second
embodiment. In this embodiment, the retaining structure 28a
includes four plates, i.e., a first plate 284, a second plate 282,
a third plate 286 and a fourth plate 288. A wick 280 in the form of
a layer is provided on an outer surface of each of the four plates
282, 284, 286, 288. The first plate 284 and second plate 282 are
the same as the two plates 282, 284 of the retaining structure 28
of the first embodiment. The third plate 286 and the fourth plate
288 are identical to each other. The third plate 286 and the fourth
plate 288 are arranged at opposite sides of the first plate 284,
and are equidistantly spaced from the first plate 284. Both the
third plate 286 and the fourth plate 288 perpendicularly cross the
second plate 282. Thus the first plate 284, the third plate 286 and
the fourth plate 288 are parallel to each other, and all are
perpendicular to the second plate 282.
[0026] A length of each of the third plate 286 and the fourth plate
288 is the same as that of the first plate 284 and the second plate
282, i.e., the four plates 282, 284, 286, 288 have the same length.
A width of each of the third plate 286 and the fourth plate 288 is
less than that of each of the first plate 284 and the second plate
282. Lateral edges of the first plate 284, the second plate 282,
the third plate 286 and the fourth plate 288 are located on an
imaginary cylinder, which has a diameter approximately the same as
the inner diameter of the tube 26. Thus when the retaining
structure 28a is assembled into the tube 26 of the heat pipe 20,
lateral edges of all of the four plates 282, 284, 286, 288 attach
to the first wick 260 of the tube 26 to enhance the rigidity of the
tube 26. The interspace 268 of the heat pipe 20 is thus separated
into eight channels 266a by the four plates 282, 284, 286, 288, for
vaporized working fluid flowing upwardly in order to dissipate
heat.
[0027] FIG. 5 shows a retaining structure 28b according to a third
embodiment. In this embodiment, the retaining structure 28b
includes a hollow core 281, and a plurality of supporting fins 282b
extending radially from an outer circumferential surface of the
core 281. Similar to the previous embodiment, a wick 280 in the
form of a layer is provided on an outer surface of each supporting
fin 282b, and on the outer circumferential surface of the core 281.
In addition, an additional wick 285 is arranged inside the core
281, for providing an additional path for condensed working fluid
to flow back to the bottom of the heat pipe 20. The core 281 has an
outer diameter smaller than the inner diameter of the tube 26. The
supporting fins 282b are identical to each other, and are evenly
angularly spaced from each other around the outer surface of the
core 281. Each supporting fin 282b is rectangular. Lateral edges of
the supporting fins 282b are located on an imaginary cylinder,
which has a diameter substantially the same as the inner diameter
of the tube 26. In this embodiment, there are eight supporting fins
282b formed around the core 281. When the retaining structure 28b
is assembled into the tube 26, all of the eight supporting fins
282b abut the tube 26, and eight channels 266b are defined in the
heat pipe 20 between neighboring supporting fins 282b for moving of
vaporized working fluid.
[0028] FIG. 6 shows a retaining structure 28c according to a fourth
embodiment. The retaining structure 28c of this embodiment includes
a core 281c and a plurality of supporting fins 282c. A wick 280 in
the form of a layer is provided on an outer surface of each of the
supporting fins 282c, and on an outer circumferential surface of
the core 281c. The core 281c is hollow, and is in the shape of a
frustum of a circular cone. An outer diameter of the core 281c
gradually decreases from bottom to top; and an inner diameter of
the core 281c gradually decreases from bottom to top, corresponding
to the outer diameter. Thus the core 281c defines a passage 283c
therein, with a diameter of the passage 283c gradually decreasing
from bottom to top. A maximum outer diameter of the core 281c at
the bottom is substantially the same as the inner diameter of the
tube 26.
[0029] The supporting fins 282c are formed on the outer
circumferential surface of the core 281c, and are identical to each
other. Each supporting fin 282c is triangular. A with of the
supporting fin 282c as measured in a radial direction gradually
decreases from top to bottom. A lateral edge of each supporting fin
282c is vertical. When the retaining structure 28c is assembled
into the tube 26, the lateral edges of all of the supporting fins
282c abut the tube 26 to enhance the rigidity of the tube 26. In
addition, since the core 281c at the bottom end has the outer
diameter approximately equal to the inner diameter of the tube 26,
the bottom end of the core 281c can also abut the tube 26. The
passage 283c in the core 281c acts as a convergent channel for
moving of vaporized working fluid. Thus the vaporized working fluid
flowing in the passage 283c of the core 281c and the condensed
wording fluid flowing in the wick 280 on the retaining structure
28c and in the first wick 260 on the tube 26 are isolated from each
other by the core 281c, and interaction between the vaporized
working fluid and condensed wording fluid is avoided. Accordingly,
a heat transfer capability of the heat pipe 20 with the retaining
structure 28c is enhanced.
[0030] FIG. 7 shows a retaining structure 28d according to a fifth
embodiment. The retaining structure 28d of this embodiment includes
a hollow core 281d, and a plurality of supporting fins 282d around
the core 281d. A wick 280 in the form of a layer is provided on an
outer surface of each supporting fin 282d, and on an outer
circumferential surface of the core 281d. In this embodiment, the
core 281d includes an upper portion 287d and a lower portion 289d.
The lower portion 289d of the core 281d has an outer diameter
gradually decreasing from bottom to top, while the upper portion
287d of the core 281d has a uniform outer diameter. A maximum outer
diameter of the lower portion 289d of the core 281d is at the
bottom of the core 281d, and is substantially equal to the inner
diameter of the tube 26. A minimum outer diameter of the lower
portion 289d of the core 281d is at a top of the lower portion 289d
of the core 281d, and is larger than the diameter of the upper
portion 287d of the core 281d. A generally annular, horizontal step
285d is formed at the top of the lower portion 289d of the core
281d. The step 285d surrounds and adjoins an outer periphery of a
bottom of the upper portion 287d of the core 281d.
[0031] The supporting fins 282d are identical to each other. A
lateral edge of each supporting fin 282d is vertical. All of the
lateral edges of the supporting fins 282d are located on an
imaginary cylinder, which has a diameter approximately the same as
the inner diameter of the tube 26. Each supporting fin 282d
includes an upper section 29 extending radially and outwardly from
the upper portion 287d of the core 281d, and a lower section 30
extending radially and outwardly from the lower portion 289d of the
core 281d. The upper section 29 of each supporting fin 282d is
rectangular, while the lower section 30 of each supporting fin 282d
is triangular. When the retaining structure 28d is assembled into
the tube 26, lateral edges of the supporting fins 282d abut the
first wick 260 of the tube 26 to enhance the rigidity of the tube
26. The bottom end of the core 281d abuts the tube 26, and the
hollow core 281d defines a channel 283d therein for moving of
vaporized working fluid.
[0032] It is to be understood, however, that even though numerous
characteristics and advantages of various embodiments have been set
forth in the foregoing description, together with details of the
structures and functions 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 disclosure to the full extent indicated by the
broad general meaning of the terms in which the appended claims are
expressed.
* * * * *