U.S. patent application number 12/869930 was filed with the patent office on 2012-03-01 for flat heat pipe with composite capillary structure.
This patent application is currently assigned to FORCECON TECHNOLOGY CO., LTD.. Invention is credited to Yen-Chen Chen, Sin-Wei HE, Ming-Cyuan Shih.
Application Number | 20120048516 12/869930 |
Document ID | / |
Family ID | 45695581 |
Filed Date | 2012-03-01 |
United States Patent
Application |
20120048516 |
Kind Code |
A1 |
HE; Sin-Wei ; et
al. |
March 1, 2012 |
FLAT HEAT PIPE WITH COMPOSITE CAPILLARY STRUCTURE
Abstract
A flat heat pipe with a composite capillary structure has a flat
pipe with a flat and enclosed hollow pipe body including a top
wall, a bottom wall, two lateral walls and a chamber. The flat pipe
has an evaporation section and a condensation section. The
elongated mesh grid is located onto either of the top and bottom
walls in the chamber. The elongated mesh grid is extended from the
evaporation section to the condensation section. The long porous
sintered structure is located adjacent at least one lateral wall in
the chamber. The long porous sintered structure is extended from
the evaporation section to the condensation section. The porous
sintered structure and the elongated mesh grid are prefabricated
into a composite capillary structure. The flat heat pipe presents
excellent diversion effect and stable positioning with its better
vapor diversion space and simple manufacturing process.
Inventors: |
HE; Sin-Wei; (Jhudong,
TW) ; Chen; Yen-Chen; (Dadu, TW) ; Shih;
Ming-Cyuan; (Jhubei, TW) |
Assignee: |
FORCECON TECHNOLOGY CO.,
LTD.
Chu Pei City
TW
|
Family ID: |
45695581 |
Appl. No.: |
12/869930 |
Filed: |
August 27, 2010 |
Current U.S.
Class: |
165/104.26 |
Current CPC
Class: |
F28D 15/0233 20130101;
F28D 15/046 20130101 |
Class at
Publication: |
165/104.26 |
International
Class: |
F28D 15/04 20060101
F28D015/04 |
Claims
1. A flat heat pipe with composite capillary structure, comprising:
a flat pipe, made of metal into a flat and enclosed hollow pipe
body having a top wall, a bottom wall, two lateral walls and a
chamber; the flat pipe having an evaporation section and a
condensation section, and both ends of the flat pipe are enclosed;
moreover, the chamber is at an evacuation state; alternatively, the
chamber of the flat pipe is filled with working fluid; an elongated
mesh grid, made of metal, located in the chamber of the flat pipe;
the elongated mesh grid is extended from the evaporation section to
the condensation section of the flat pipe; a long porous sintered
structure, made of metal, located onto either position in the
chamber of the flat pipe; the long porous sintered structure is
extended from the evaporation section to the condensation section
of the flat pipe; the porous sintered structure and the elongated
mesh grid are prefabricated securely into a composite capillary
structure, and the composite capillary structure is placed between
the top and bottom walls of the chamber of the flat pipe.
2. The structure defined in claim 1, wherein a local hollowed
portion is formed at the central section of the elongated mesh grid
between the evaporation section and condensation section of the
flat pipe; moreover, a coupling surface of sintered structure is
reserved at the central section of the elongated mesh grid for
coupling the long porous sintered structure.
3. The structure defined in claim 1, wherein a single or a
plurality of spacing notches is arranged at local section of the
elongated mesh grid, in response to the bending state of the
elongated mesh grid.
4. The structure defined in claim 1, wherein at least a depressed
portion is formed at the local or central section of the long
porous sintered structure; said depressed portion is configured
into either of an inclined, bended or stepped surface.
5. The structure defined in claim 1, wherein the long porous
sintered structure is located adjacent to two lateral walls, or one
lateral wall, or at a spacing with the lateral wall in the chamber
of the flat pipe.
6. The structure defined in claim 1, wherein the inner wall of the
flat pipe is provided with a smooth surface or a grooved capillary
structure.
7. The structure defined in claim 1, wherein said corrugated
surface expanded portions are formed onto one or two sides of the
long porous sintered structure, so as to improve the evaporation
effect of the working fluid for the long porous sintered
structure.
8. The structure defined in claim 1, wherein the and the elongated
mesh grid is placed between the top and bottom walls of the chamber
of the flat pipe, and at one is placed at the interval space
between the top and bottom walls.
9. The structure defined in claim 1, wherein the molding process of
the flat heat pipe comprises the following steps: (a) preparing a
round pipe, one end pre-closed and the other end in open state; (b)
preparing an elongated mesh grid; (c) preparing a metal powder
grain of long porous sintered structure, and covering it onto the
elongated mesh grid in a sintering mould; (d) fixing the long
porous sintered structure onto the surface of the elongated mesh
grid by means of sintering, so to as prefabricate a composite
capillary structure; (e) placing the prefabricated composite
capillary structure into the round pipe; (f) pressing the round
pipe already placed into the composite capillary structure, and
convert the round pipe into a flat pipe, meanwhile enabling the
composite capillary structure to be located in the flat pipe
adjacent to the internal plane of the flat pipe; (g) filling
working fluid into the flat pipe and then evacuating said flat pipe
for sealing.
10. The structure defined in claim 9, wherein the elongated mesh
grid of the composite capillary structure is bent to form a bending
portion before the composite capillary structure is placed into the
round pipe; then the round pipe is pre-pressed and bent to convert
the round pipe into an embryo flat pipe, but the degree of pressing
only reaches 60-90% of the preset degree; the composite capillary
structure is then placed into the embryo flat pipe; then the embryo
flat pipe is pressed again to convert itself into a flat pipe,
meanwhile enabling the bending portion of the elongated mesh grid
to be extended into a straight or nearly straight shape.
11. The structure defined in claim 9, wherein the round pipe is
pre-pressed to convert into an embryo flat pipe, with the flat
cross section pressed by full or partial section.
12. The structure defined in claim 9, wherein the composite
capillary structure and the flat pipe are mated by means of
sintering before the flat pipe is filled with working fluid and
evacuated for sealing.
Description
CROSS-REFERENCE TO RELATED U.S. APPLICATIONS
[0001] Not applicable.
STATEMENT REGARDING FEDERALLY SPONSORED RESEARCH OR DEVELOPMENT
[0002] Not applicable.
NAMES OF PARTIES TO A JOINT RESEARCH AGREEMENT
[0003] Not applicable.
REFERENCE TO AN APPENDIX SUBMITTED ON COMPACT DISC
[0004] Not applicable.
BACKGROUND OF THE INVENTION
[0005] 1. Field of the Invention
[0006] The present invention relates generally to a flat heat pipe,
and more particularly to an innovative one which is configured with
a composite capillary structure and fabricated by mould
pressing.
[0007] 2. Description of Related Art Including Information
Disclosed Under 37 CFR 1.97 and 37 CFR 1.98
[0008] The heat pipe is structurally configured with a capillary
structure to enhance condensate return flow effectively.
[0009] A single capillary structure is employed by the conventional
heat pipe to facilitate the condensate return flow, while a
composite capillary structure has been developed by the industrial
operators to improve the diversion effect.
[0010] Despite that said composite capillary structure can realize
better condensate diversion effect, a larger problem is encountered
for its manufacturing process, especially when it is applied to
flat heat pipe. This is because the flat heat pipe is generally
made of round pipes by means of mould pressing, the capillary
structure in the pipe, whether in the form of mesh structure or
sintered structure, is vulnerable to deformation, deflection and
loosening during the flattening or evacuation sealing process. This
results in serious problems such as: relatively higher defects and
difficulty in quality control of finished products. But said
composite capillary structure is involved with the mating accuracy
and robustness of two capillary structures, so it is understood
that the design problems become more complex and difficult with
possible higher defects in the manufacturing and poorer industrial
benefits.
[0011] Moreover, the thickness and space of the flat heat pipe is
much less than that of the round pipe, so the vapor diversion space
is reduced considerably. With the introduction of a composite
capillary structure, the vapor diversion space will be further
lessened for the given volume and thickness in the flat heat pipe,
thus affecting its heat conduction effect.
[0012] Thus, to overcome the aforementioned problems of the prior
art, it would be an advancement if the art to provide an improved
structure that can significantly improve the efficacy.
[0013] Therefore, the inventor has provided the present invention
of practicability after deliberate experimentation and evaluation
based on years of experience in the production, development and
design of related products.
BRIEF SUMMARY OF THE INVENTION
[0014] For the condensate diversion effect: with the structural
configuration of the composite capillary structure wherein the
elongated mesh grid is mated with the long porous sintered
structure, the combined diversion structure could help realize
satisfactory diversion effect.
[0015] For the positioning of the composite capillary structure:
the elongated mesh grid provides an expanded positioning base for
the long porous sintered structure, so that the composite capillary
structure can be positioned securely. The porous sintered structure
and elongated mesh grid are combined and secured to form a
composite capillary structure, which is placed inside the chamber
of the flat pipe, so that the composite capillary structure can be
assembled to the flat pipe easily, and achieve high stability and
quality.
[0016] For the vapor diversion space: given the fact that the
elongated mesh grid is thin-profiled and the long porous sintered
structure is located adjacent to the flat pipe's lateral wall, the
present invention can provide maximum vapor diversion space for
optimized heat conductance performance.
[0017] For the manufacturing process: the composite capillary
structure of the present invention (composed of elongated mesh grid
and a long porous sintered structure) is mated with the flat heat
pipe in such a manner that the heat pipe is pre-pressed
preliminarily and the elongated mesh grid is bent. When the
composite capillary structure is placed, the heat pipe is pressed
in place. With this configuration, it is possible to provide a
simple and stable manufacturing process for mating the flat heat
pipe with the composite capillary structure.
[0018] Although the invention has been explained in relation to its
preferred embodiment, it is to be understood that many other
possible modifications and variations can be made without departing
from the spirit and scope of the invention as hereinafter
claimed.
BRIEF DESCRIPTION OF THE SEVERAL VIEWS OF THE DRAWINGS
[0019] FIG. 1 shows an upper perspective view of the preferred
embodiment of the flat heat pipe of the present invention.
[0020] FIG. 2 shows a partially exploded perspective view of the
preferred embodiment of the present invention.
[0021] FIG. 3 shows a sectional view of the preferred embodiment of
the present invention.
[0022] FIG. 4 shows another sectional view of the preferred
embodiment of the present invention (sectional state of flat heat
pipe).
[0023] FIG. 5 shows a sectional view of another preferred
embodiment of the long porous sintered structure of the present
invention.
[0024] FIG. 6 shows another sectional view of the preferred
embodiment of the long porous sintered structure of the present
invention (sectional state of flat heat pipe).
[0025] FIG. 7 shows a schematic view of the present invention
wherein the elongated mesh grid is provided with a local hollowed
portion.
[0026] FIG. 8 shows a schematic view of the present invention
wherein the elongated mesh grid is provided with a notch.
[0027] FIG. 9 shows sectional view of another preferred embodiment
of the long porous sintered structure of the present invention.
[0028] FIG. 10 shows a perspective view of the preferred embodiment
in FIG. 9.
[0029] FIG. 11 shows a schematic view of the present invention
wherein the long porous sintered structure is provided with a
depressed portion.
[0030] FIG. 12 shows a schematic view of the present invention
wherein a grooved capillary structure is formed onto the inner wall
of the flat pipe.
[0031] FIG. 13 shows a schematic view of the molding process of the
present invention.
[0032] FIG. 14 shows a schematic view of the other molding process
of the present invention.
[0033] FIG. 15 shows a schematic view of the present invention
wherein the embryo flat pipe is pre-pressed and converted from the
round pipe is arranged at a local section.
[0034] FIG. 16 shows another schematic view of the long porous
sintered structure of the present invention.
[0035] FIG. 17 shows another schematic view of the elongated mesh
grid of the present invention.
DETAILED DESCRIPTION OF THE INVENTION
[0036] FIGS. 1-4 depict preferred embodiments of a flat heat pipe
of the present invention with a composite capillary structure,
which, however, are provided for only explanatory objective for
patent claims.
[0037] Said flat heat pipe A comprises a flat pipe 10, made of
metal into a flat and enclosed hollow pipe body, having a top wall
11, a bottom wall 12, two lateral walls 13, 14 and a chamber 15.
The flat pipe 10 has an evaporation section 16 and a condensation
section 17, and both ends of the flat pipe 10 are enclosed (shown
by C1, C2 in FIG. 1). Moreover, the chamber 15 is at an evacuation
state. Alternatively, the chamber 15 of the flat pipe 10 is filled
with working fluid.
At least one elongated mesh grid 20, made of metal, is located onto
either of the top and bottom walls 11, 12 in the chamber 15 of the
flat pipe 10. The elongated mesh grid 20 is extended from the
evaporation section 16 to the condensation section 17 of the flat
pipe 10.
[0038] At least one long porous sintered structure 30, made of
metal, is located onto either position in the chamber 15 of the
flat pipe 10 (the long porous sintered structure 30 of the
preferred embodiment is divided into two parts adjacent to two
lateral walls 13, 14). The long porous sintered structure 30 is
extended from the evaporation section 16 to the condensation
section 17 of the flat pipe 10.
[0039] Moreover, the porous sintered structure 30 and the elongated
mesh grid 20 are prefabricated securely into a composite capillary
structure B, and the composite capillary structure B is placed
between the top and bottom walls 11, 12 of the chamber 15 of the
flat pipe 10.
[0040] Referring to FIG. 7, a local hollowed portion 21 is formed
at the central section of the elongated mesh grid 20 between the
evaporation section 16 and condensation section 17 of the flat pipe
10. Moreover, a coupling surface of sintered structure 22 is
reserved at the central section of the elongated mesh grid 20 for
coupling the long porous sintered structure 30. In this preferred
embodiment, the elongated mesh grid 20 can be further shrunk to
provide a larger vapor diversion space in response to the
space-saving flat heat pipe, provided that the mating state of the
long porous sintered structure 30 is not affected.
[0041] Referring to FIG. 8, a single or a plurality of spacing
notches 23 (V-shaped or straight pattern) is arranged at local
section of the elongated mesh grid 20, in response to the bending
state of the elongated mesh grid 20. When the elongated mesh grid
20 is bent in tune with the flat heat pipe, the bending portion
permits one to prevent the corrugation with the configuration of
said notch 23. The mesh structure will generate a corrugated
surface at the bending portion without the design of notch.
[0042] Referring also to FIGS. 9 and 10, the long porous sintered
structure 30 is located within the chamber 15 of the flat pipe 10
at a spacing with the lateral walls 13, 14. With this
configuration, a vapor channel is formed between the long porous
sintered structure 30 and lateral walls 13, 14 to improve the
diversion effect. Also, the cross section of the long porous
sintered structure 30 of the preferred embodiment is of a
rectangular shape.
[0043] Referring to FIG. 11, at least one depressed portion 31 is
formed at the local or central section of the long porous sintered
structure 30. With the configuration of the depressed portion 31,
the space of the vapor channel can be increased, and the long
porous sintered structure 30 can be locally released to meet the
bending state of the long porous sintered structure 30 when the
flat heat pipe is bent. Furthermore, said depressed portion 31 is
configured into either of an inclined, bended or stepped
surface.
[0044] Of which, the inner wall of the flat pipe 10 is of a smooth
surface (shown in FIG. 4). Alternatively, referring to FIG. 12, the
inner wall of the flat pipe 10 is provided with a grooved capillary
structure 18. A satisfactory condensate diversion effect can be
realized via the configuration of said grooved capillary structure
18.
[0045] Based on above-specified structural configuration for the
flat heat pipe of the present invention with a composite capillary
structure, the molding process of the preferred embodiment is
described in the following steps (referring to FIG. 13): [0046] (a)
Prepare a round pipe 10B, one end pre-closed and the other end in
open state; [0047] (b) Prepare at least an elongated mesh grid 20;
[0048] (c) Prepare at least a metal powder grain 30B of long porous
sintered structure, and cover it onto the elongated mesh grid 20 in
a sintering mould 40; [0049] (d) Fix the long porous sintered
structure 30 onto the surface of the elongated mesh grid 20 by
means of sintering, so to as prefabricate a composite capillary
structure B; [0050] (e) Place the prefabricated composite capillary
structure B into the round pipe 10B; [0051] (f) Press the round
pipe 10B already placed into the composite capillary structure B,
and convert the round pipe 10B into a flat pipe 10D, meanwhile
enabling the composite capillary structure B to be located in the
flat pipe 10D adjacent to the internal plane of the flat pipe 10D;
[0052] (g) Enable mating of the composite capillary structure B and
flat pipe 10D by means of sintering; [0053] (h) Fill working fluid
into the flat pipe 10D and then evacuate it for sealing.
[0054] Alternatively, another molding process of the preferred
embodiment is described in the following steps (referring to FIG.
14): [0055] (a) Prepare a metal round pipe 10B, one end pre-closed
and the other end in open state; [0056] (b) Prepare at least an
elongated mesh grid 20; [0057] (c) Prepare at least a metal powder
grain 30B of long porous sintered structure, and cover it onto the
elongated mesh grid 20 in a sintering mould 40; [0058] (d) Fix the
long porous sintered structure 30 onto the surface of the elongated
mesh grid 20 by means of sintering, so to as prefabricate a
composite capillary structure B; [0059] (e) Bend the elongated mesh
grid 20 of the composite capillary structure B so as to form a
bending portion on the elongated mesh grid 20; [0060] (f) Pre-press
the round pipe 10B for the first time to convert the round pipe 10B
into an embryo flat pipe 10C, but the degree of pressing only
reaches 60%-90% of the preset degree; [0061] (g) Place the
composite capillary structure B into the round pipe 10C obtained in
aforementioned step (d); [0062] (h) Press again the embryo flat
pipe 10C already placed into the composite capillary structure B,
and convert it into a shaped flat pipe 10D, meanwhile enabling the
long porous sintered structure 30 of the composite capillary
structure B to be located onto the lateral wall of the flat pipe
10D adjacent to the internal plane of the flat pipe 10D, and also
enabling the bending portion 24 of the elongated mesh grid 20 to be
extended into a straight or nearly straight shape; [0063] (i)
Enable mating of the composite capillary structure B and flat pipe
10D (by means of sintering); [0064] (j) Fill working fluid into the
flat pipe 10D and then evacuate it for sealing, thereby fabricating
a finished flat heat pipe of present invention with composite
capillary structure.
[0065] In the above methods, the long porous sintered structure 30
of the composite capillary structure B is preferably fixed at two
sides on the surface of the elongated mesh grid 20.
[0066] Moreover, for the embryo flat pipe 10C pre-pressed by the
round pipe 10B, its flat cross section is pressed by full section.
Alternatively, referring to FIG. 15, the flat cross section is
pressed by partial section. The pre-pressed flat cross section is
used for preventing overturn and displacement of composite
capillary structure B not yet sintered.
[0067] Referring to FIG. 16, corrugated surface expanded portions
32 (rectangular, bended, stepped and reversed shapes) are formed
onto one or two sides of the long porous sintered structure 30, so
the evaporation effect of the working fluid for the long porous
sintered structure 30 can be improved to obtain better heat
conduction efficiency.
[0068] Referring to FIG. 17, said elongated mesh grid can be placed
in the interval space between the top and bottom walls 11, 12 of
the chamber 15 of the flat pipe 10.
* * * * *