U.S. patent application number 12/698998 was filed with the patent office on 2011-05-12 for plate-type heat pipe.
This patent application is currently assigned to FU ZHUN PRECISION INDUSTRY (SHEN ZHEN) CO., LTD.. Invention is credited to Chuen-Shu Hou, Jiang-Jun Hu, Chao Xu.
Application Number | 20110108243 12/698998 |
Document ID | / |
Family ID | 43973273 |
Filed Date | 2011-05-12 |
United States Patent
Application |
20110108243 |
Kind Code |
A1 |
Hou; Chuen-Shu ; et
al. |
May 12, 2011 |
PLATE-TYPE HEAT PIPE
Abstract
An exemplary plate-type heat pipe includes a hermetic container,
working fluid contained in the container, a first wick portion and
two second wick portions formed on inner surfaces of the container.
The container includes an evaporating plate and a condensing plate
facing each other. The evaporating plate includes a heat absorbing
portion, two transition portions extending outwardly and upwardly
from opposite ends of the heat absorbing portion, respectively, and
two extending portions extending outwardly from outer ends of the
transition portions, respectively. The first wick portion is formed
on an inner surface of the heat absorbing portion. The second wick
portions are formed on inner surfaces of the transition portions,
respectively. The third wick portions are formed on inner surfaces
of the extending portions, respectively. The third wick portions
define capillary pores and a plurality of holes therein.
Inventors: |
Hou; Chuen-Shu; (Tu-Cheng,
TW) ; Hu; Jiang-Jun; (Shenzhen City, CN) ; Xu;
Chao; (Shenzhen City, CN) |
Assignee: |
FU ZHUN PRECISION INDUSTRY (SHEN
ZHEN) CO., LTD.
Shenzhen City
CN
FOXCONN TECHNOLOGY CO., LTD.
Tu-Cheng
TW
|
Family ID: |
43973273 |
Appl. No.: |
12/698998 |
Filed: |
February 2, 2010 |
Current U.S.
Class: |
165/104.26 |
Current CPC
Class: |
F28D 15/046
20130101 |
Class at
Publication: |
165/104.26 |
International
Class: |
F28D 15/02 20060101
F28D015/02 |
Foreign Application Data
Date |
Code |
Application Number |
Nov 12, 2009 |
CN |
200910309578.4 |
Claims
1. A plate-type heat pipe comprising: a condensing plate; an
evaporating plate cooperating with the condensing plate to define a
hermetic container, the evaporating plate comprising a heat
absorbing portion and two extending portions located at opposite
sides of the heat absorbing portion; working fluid contained in the
container; and a first wick portion formed on an inner surface of
the heat absorbing portion, and two second wick portions formed on
inner surfaces of the extending portions, respectively, the second
wick portions defining a plurality of holes therein.
2. The plate-type heat pipe of claim 1, wherein the holes are
through holes, each of which extends through a thickness of the
corresponding second wick portion.
3. The plate-type heat pipe of claim 2, wherein a number of
auxiliary wick portions are received in the through holes,
respectively, and contact the inner surfaces of the extending
portions.
4. The plate-type heat pipe of claim 3, wherein each of the
auxiliary wick portions is thinner than the second wick portion,
and comprises a first side contacting the inner surface of the
corresponding extending portion of the evaporating plate and an
opposite second side.
5. The plate-type heat pipe of claim 4, wherein a cross-section of
each of the auxiliary wick portions is a rectangle, the second side
being parallel to the first side.
6. The plate-type heat pipe of claim 4, wherein a cross-section of
each of the auxiliary wick portions is a trapezoid, the second side
being aslant relative to the first side.
7. The plate-type heat pipe of claim 6, wherein the auxiliary wick
portions are all oriented toward the same direction.
8. The plate-type heat pipe of claim 4, wherein the second side of
each of the auxiliary wick portions is concave, and a thickness of
each of the auxiliary wick portions gradually increases from a
central portion thereof to each of opposite ends thereof.
9. The plate-type heat pipe of claim 1, wherein the evaporating
plate further comprises two transition portions extending upwardly
and outwardly from opposite edges of the heat absorbing portion and
connecting with the two extending portions, respectively, and two
third wick portions are formed on inner surfaces of the transition
portions, respectively.
10. The plate-type heat pipe of claim 1, wherein the evaporating
plate further comprises two sidewalls extending upwardly from outer
ends of the two extending portions, respectively, and connecting
with the condensing plate, and two fourth wick portions are formed
on inner surfaces of the sidewalls, respectively.
11. The plate-type heat pipe of claim 10, wherein a wick member is
adhered on an inner surface of the condensing plate and connects
with the fourth wick portions.
12. The plate-type heat pipe of claim 1, wherein a plurality of
holes is defined in the first wick portion.
13. A plate-type heat pipe comprising: a hermetic container
comprising an evaporating plate and a condensing plate facing each
other, the evaporating plate comprising a heat absorbing portion
adapted for contacting a heat-generating component, two transition
portions extending aslant from opposite lateral sides of the heat
absorbing portion, respectively, and two extending portions
extending outwardly from outer sides of the transition portions,
respectively, the extending portions being closer to the condensing
plate than the heat absorbing portion; working fluid contained in
the container; and a wick member formed on an inner surface of the
evaporating plate, comprising a first wick portion formed on an
inner surface of the heat absorbing portion, two second wick
portions formed on inner surfaces of the transition portions,
respectively, and two third wick portions formed on inner surfaces
of the extending portions, respectively, the third wick portions
defining a plurality of holes.
14. The plate-type heat pipe of claim 13, wherein the holes extends
through the third wick portions in the thickness direction of the
third wick portions.
15. The plate-type heat pipe of claim 14, wherein a plurality of
auxiliary wick are arranged in the holes of the third wick portions
and contacts the inner surfaces of the extending portions.
16. The plate-type heat pipe of claim 15, wherein each of the
auxiliary wicks is thinner than the third wick portion.
17. The plate-type heat pipe of claim 15, wherein the evaporating
plate further comprises two sidewall extending upwardly from outer
ends of the extending portions, respectively and connect opposite
ends of the condensing plate, respectively, two fourth wick portion
are formed on inner surfaces of the sidewalls.
18. The plate-type heat pipe of claim 17, wherein another wick
member is adhered on an inner surface of the condensing plate and
connects with the fourth wick portions to form a continuous wick on
an inner surface of the container.
19. The plate-type heat pipe of claim 13, wherein the first wick
portion is thinner than second wick portion and the third wick
portion.
20. The plate-type heat pipe of claim 19, wherein a plurality of
holes is defined in the first wick portion.
Description
BACKGROUND
[0001] 1. Technical Field
[0002] The present disclosure relates to heat pipes and, more
particularly, to a plate-type heat pipe having good heat
dissipation efficiency and stable and reliable performance.
[0003] 2. Description of Related Art
[0004] Generally, plate-type heat pipes efficiently dissipate heat
from heat-generating components such as a central processing unit
(CPU) of a computer. A conventional plate-type heat pipe comprises
a top plate and a bottom cover hermetically contacting the top
plate to form a container. A wick structure is adhered to an inner
surface of the bottom cover. Working fluid is contained in the
container. All parts of the wick structure have the same thickness.
When the bottom cover of the plate-type heat pipe absorbs heat of
the heat-generating component, the working fluid is vaporized to
absorb the heat of the bottom cover.
[0005] If the wick structure is too thick, a part of the vaporized
working fluid is retarded by the wick structure when the vaporized
working fluid is escaping from the wick structure toward the top
plate. Therefore, a plurality of bubbles is formed in and on the
wick structure. The bubbles tend to block pores of the wick
structure, and retard the flow of condensed working fluid into the
wick structure. When this happens, the amount of condensed working
fluid contained in the wick structure decreases. What working fluid
there is in the wick structure may absorb the heat of the bottom
cover too slowly, whereby heat is accumulated on the bottom cover,
and the plate-type heat pipe overheats. Conversely, if the wick
structure is too thin, the working fluid contained in the wick
structure is liable to be dried off altogether. When this happens,
the plate-type heat pipe will be destroyed.
[0006] What is needed, therefore, is a plate-type heat pipe having
good heat dissipation efficiency and stable, reliable
performance.
BRIEF DESCRIPTION OF THE DRAWINGS
[0007] In the drawings, all the views are schematic.
[0008] FIG. 1 is a cross-sectional view of a plate-type heat pipe
in accordance with a first embodiment of the present disclosure,
the plate-type heat pipe including an evaporating plate having two
extending portions, and two wick portions arranged on the extending
portions.
[0009] FIG. 2 is an isometric view of part of one of the wick
portions arranged on the corresponding extending portion of FIG.
1.
[0010] FIG. 3 is an enlarged, cross-sectional view of part of the
wick portion and extending portion of FIG. 2, taken along line
III-III thereof.
[0011] FIG. 4 is similar to FIG. 3, but showing part of an
extending portion arrangement of an evaporating plate of a
plate-type heat pipe in accordance with a second embodiment of the
present disclosure, with a wick portion and a number of auxiliary
wick portions received in the wick portion.
[0012] FIG. 5 is similar to FIG. 3, but showing part of an
extending portion arrangement of an evaporating plate of a
plate-type heat pipe in accordance with a third embodiment of the
present disclosure, with a wick portion and a number of auxiliary
wick portions received in the wick portion.
[0013] FIG. 6 is similar to FIG. 3, but showing part of an
extending portion arrangement of an evaporating plate of a
plate-type heat pipe in accordance with a fourth embodiment of the
present disclosure, with a wick portion and a number of auxiliary
wick portions received in the wick portion.
[0014] FIG. 7 is an isometric view of a wick member of an
evaporating plate of a plate-type heat pipe in accordance with a
fifth embodiment of the present disclosure.
DETAILED DESCRIPTION
[0015] Referring to FIGS. 1-2, a plate-type heat pipe in accordance
with a first embodiment of the present disclosure is shown. The
plate-type heat pipe includes a hermetic container 10, a continuous
wick structure 30 mounted on an inner surface of the container 10,
and working fluid (not shown) contained in the container 10.
[0016] The container 10 is made of copper, aluminum, or an alloy
thereof. The container 10 includes an elongated condensing plate 11
and a bowl-shaped evaporating plate 13 integrally formed as a
single, one-piece, monolithic body without any seams. The
evaporating plate 13 absorbs heat of heat-generating components
(not shown) such as electronic devices. Then the condensing plate
11 dissipates the heat, transferred from the evaporating plate 13,
to the ambient environment. In alternative embodiments, the
elongated condensing plate 11 and the bowl-shaped evaporating plate
13 can be distinct pieces, with the bowl-shaped evaporating plate
13 hermetically contacting the condensing plate 11.
[0017] The evaporating plate 13 includes an elongated heat
absorbing portion 131, two transition portions 133, two extending
portions 134, and two sidewalls 135. The two transition portions
133 extend upwardly and outwardly from opposite lateral edges of
the heat absorbing portion 131, respectively, and are symmetrically
opposite each other. The two extending portions 134 extend
outwardly along opposite horizontal directions from outer edges of
the transition portions 133, respectively. The sidewalls 135 extend
upwardly from outer edges of the extending portions 134,
respectively. The sidewalls 135 are perpendicular to the extending
portions 134. The extending portions 134 are parallel to the heat
absorbing portion 131, and are closer to the condensing plate 11
than the heat absorbing portion 131. In the illustrated embodiment,
top ends of the sidewalls 135 are integrally formed with two ends
of the condensing plate 11. That is, the evaporating plate 13 and
the condensing plate 11 are a single body of the same material
without any seams. In other embodiments, the evaporating plate 13
and the condensing plate 11 can be separate bodies hermetically
connected together.
[0018] The wick structure 30 is made of sintered metallic powder,
and includes an elongated first wick member 31 and a second wick
member 33. The first wick member 31 is adhered to an inner surface
of the condensing plate 11. The second wick member 33 is adhered to
an inner surface of the evaporating plate 13. The second wick
member 33 is adapted for providing a capillary force to draw
condensed working fluid from the first wick member 31 back toward a
middle portion of the second wick member 33. Opposite ends of the
second wick structure 33 interconnect opposite ends of the first
wick member 31, respectively, thereby forming the continuous wick
structure 30.
[0019] Referring also to FIG. 3, the second wick member includes an
elongated first wick portion 331, two second wick portions 333, two
third wick portions 335, and two fourth wick portions 337. The
first wick portion 331, the second wick portions 333, and the third
wick portions 335 are spaced from the first wick member 31.
[0020] The first wick portion 331 is adhered to an inner surface of
the heat absorbing portion 131 of the evaporating plate 13. The
second wick portions 333 extend upwardly and outwardly from
opposite ends of the first wick portion 331, respectively, and are
symmetrically opposite each other. The second wick portions 333 are
adhered to inner surfaces of the transition portions 133 of the
evaporating plate 13. The first wick portion 331 is thinner than
each of the second wick portions 333 and each of the third wick
portions 335. Thus, in general, the working fluid contained in the
first wick portion 331 is vaporized faster than working fluid at a
comparable location in a conventional plate-type heat pipe.
Accordingly, the heat of the heat absorbing portion 131 is
transferred quickly. The third wick portions 335 are horizontal,
and extend outwardly from the second wick portions 333,
respectively. The third wick portions 335 are adhered to inner
surfaces of the extending portions 134 of the evaporating plate 13.
The fourth wick portions 337 are adhered to inner surfaces of the
sidewalls 135 of the evaporating plate 13, and perpendicularly
connect outer ends of the third wick portions 335,
respectively.
[0021] Each of the third wick portions 335 defines a plurality of
rectangular or square through holes 3353 therein. In the
illustrated embodiment, the through holes 3313 are arranged in a
regular m.times.n array. The working fluid contained in the first
wick portion 331 absorbs the heat of the heat absorbing portion 131
quickly, and then is vaporized. The vaporized working fluid moves
to the first wick member 31 to dissipate the heat, and condenses at
the first wick member 31. The fourth wick portions 337, third wick
portions 335, and second wick portions 333 cooperatively guide the
condensing working fluid contained in or accumulated on the first
wick member 31 back to the first wick portion 331. Because the
through holes 3353 are defined in the third wick portions 335, a
portion of the condensing working fluid is contained in the through
holes 3353. Thus, the amount of working fluid contained in the
second wick member 33 is increased relative to working fluid at a
comparable location in a conventional plate-type heat pipe. The
working fluid contained in the through holes 3353 can ensure that a
quantity of the condensing working fluid in the first wick portion
331 is sufficient even though evaporation of the working fluid in
the first wick portion 331 is faster. Therefore, the plate-type
heat pipe avoids becoming dried off. Thus, the plate-type heat pipe
has stable, reliable performance. In alternative embodiments, the
through holes 3353 can be triangular, circular, oval-shaped,
elliptical, etc.
[0022] Referring to FIG. 4, this shows an extending portion
arrangement of a plate-type heat pipe in accordance with a second
embodiment of the present disclosure. A third wick portion 335 and
a plurality of auxiliary wick portions 332 are adhered to an inner
surface of an extending portion 134. The plate-type heat pipe in
accordance with the second embodiment, is substantially the same as
that shown in FIG. 1, except the auxiliary wick portions 332.
Therefore a detailed description of most parts of the structure of
the plate-type heat pipe in accordance with the second embodiment
is omitted. In the illustrated embodiment, the auxiliary wick
portions 332 fill bottom ends of through holes 3353, respectively.
Bottom end surfaces of the auxiliary wick portions 332 and a bottom
surface of the third wick portion 335 are coplanar with one
another, and are adhered to the inner surface of the extending
portion 134. The auxiliary wick portions 332 have the same
thickness, and are much thinner than the third wick portion 335.
For example, each auxiliary wick portion 332 is less than half the
thickness of the third wick portion 335.
[0023] Because the auxiliary wick portions 332 are much thinner
than the third wick portion 335, a majority of each of the through
holes 3353 is available to accommodate working fluid. The
condensing working fluid is contained in pores of the second wick
member 33 and the upper portions of the through holes 3353 not
occupied by the auxiliary wick portions 332. Therefore, a quantity
of the condensing working fluid in the second wick member 33 is
increased relative to working fluid at a comparable location in a
conventional plate-type heat pipe. In addition, a capillary force
of the second wick member 33 is improved because of the auxiliary
wick portions 332 filling the bottoms of the through holes 3353 of
the third wick portion 335. Therefore, the condensed working fluid
flows back to the first wick portion 331 more quickly. Thus, stable
and reliable performance of the plate-type heat pipe can be
ensured.
[0024] Referring to FIG. 5, this shows an extending portion
arrangement of a plate-type heat pipe in accordance with a third
embodiment of the present disclosure. A third wick portion 335 and
a plurality of auxiliary wick portions 334 are adhered to an inner
surface of an extending portion 134. A difference between the
plate-type heat pipe of the third embodiment and the plate-type
heat pipe shown in FIG. 4 is only in the shape of the auxiliary
wick portions 334. In the third embodiment, a cross-section of each
of the auxiliary wick portions 334 is a trapezoid. Each auxiliary
wick portion 334 has a smaller end, and a larger end opposite to
the smaller end. The smaller ends of the auxiliary wick portions
334 are all oriented toward the same direction. A top side of each
auxiliary wick portion 334 is aslant, and a bottom side of each
auxiliary wick portion 334 is horizontal and adhered to the inner
surface of the extending portion 134. The larger ends of the
auxiliary wick portions 334 are all thinner than the third wick
portion 335.
[0025] Referring to FIG. 6, this shows an extending portion
arrangement of a plate-type heat pipe in accordance with a fourth
embodiment of the present disclosure. A third wick portion 335 and
a plurality of auxiliary wick portions 336 are adhered to an inner
surface of an extending portion 134. A difference between the
plate-type heat pipe of the fourth embodiment and the plate-type
heat pipe shown in FIG. 4 is only in the shape of the auxiliary
wick portions 336. In the fourth embodiment, a cross-section of
each of the auxiliary wick portions 336 has a top side being
concave, and a bottom side being horizontal. The bottom sides are
adhered to the inner surface of the extending portion 134. A
thickness of each auxiliary wick portion 336 gradually increases
from a central portion thereof to each of opposite ends thereof.
The opposite ends of the auxiliary wick portions 336 are all
thinner than the third wick portion 335.
[0026] Referring to FIG. 7, this shows a second wick member 73 of a
plate-type heat pipe of a fifth embodiment of the present
disclosure. The second wick member 73 is similar to the second wick
member 33 of the first embodiment, except that a plurality of
rectangular or square through holes 7313 is defined in a first wick
portion 731. Therefore the vaporized working fluid in the first
wick portion 731 escapes from the first wick portion 731 via the
through holes 7313 quickly. Accordingly, unlike in conventional
plate-type heat pipes, few or even no bubbles accumulate in the
first wick portion 731 when the plate-type heat pipe is in
operation. Thus, the heat dissipation efficiency of the plate-type
heat pipe is improved.
[0027] 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.
* * * * *