U.S. patent application number 13/415703 was filed with the patent office on 2012-09-13 for flat heat pipe with sectional differences and method for manufacturing the same.
This patent application is currently assigned to COOLER MASTER CO., LTD.. Invention is credited to Chang-Yin CHEN, Lei-Lei LIU, Lin-Chuan YEN.
Application Number | 20120227933 13/415703 |
Document ID | / |
Family ID | 46794455 |
Filed Date | 2012-09-13 |
United States Patent
Application |
20120227933 |
Kind Code |
A1 |
CHEN; Chang-Yin ; et
al. |
September 13, 2012 |
FLAT HEAT PIPE WITH SECTIONAL DIFFERENCES AND METHOD FOR
MANUFACTURING THE SAME
Abstract
The present invention provides a flat heat pipe with sectional
differences and a method for manufacturing the same. The heat pipe
has a flat hollow pipe body. A working fluid is sealed in the pipe
body. The pipe body is provided along its length with a plurality
of flat sectional difference portions having different widths. A
connecting portion is formed between the sectional difference
portions. The inner wall of the pipe body is formed with a
plurality of grooves. The pitch between the grooves in the
sectional difference portion of a relatively large width is larger
than the pitch between the grooves in the sectional difference
portion of a relatively small width.
Inventors: |
CHEN; Chang-Yin; (New Taipei
City, TW) ; LIU; Lei-Lei; (Hui Zhou City, CN)
; YEN; Lin-Chuan; (New Taipei City, TW) |
Assignee: |
COOLER MASTER CO., LTD.
|
Family ID: |
46794455 |
Appl. No.: |
13/415703 |
Filed: |
March 8, 2012 |
Current U.S.
Class: |
165/104.21 ;
29/890.032 |
Current CPC
Class: |
B21D 53/06 20130101;
F28D 15/0233 20130101; B23P 15/26 20130101; H01L 2924/0002
20130101; F28D 15/046 20130101; H01L 23/427 20130101; Y10T 29/49384
20150115; Y10T 29/49353 20150115; H01L 2924/0002 20130101; Y10T
29/49385 20150115; B21D 22/025 20130101; B23P 2700/09 20130101;
H01L 2924/00 20130101 |
Class at
Publication: |
165/104.21 ;
29/890.032 |
International
Class: |
F28D 15/02 20060101
F28D015/02; B21D 53/02 20060101 B21D053/02 |
Foreign Application Data
Date |
Code |
Application Number |
Mar 10, 2011 |
TW |
100108124 |
Claims
1. A flat heat pipe with sectional differences, configured to have
a flat hollow pipe body, a working fluid being sealed in the pipe
body, the pipe body being provided along its length with a
plurality of flat sectional difference portions having different
widths, a connecting portion being formed between each sectional
difference portions, wherein an inner wall of the pipe body is
formed with a plurality of grooves, a pitch between the grooves in
the sectional difference portion of a relatively large width is
larger than a pitch between the grooves in the sectional difference
portion of a relatively small width.
2. The flat heat pipe with sectional differences according to claim
1, wherein the connecting portion is integrally formed between each
sectional difference portions to connect the respective sectional
difference portions.
3. The flat heat pipe with sectional differences according to claim
1, wherein the sectional difference portion having a relatively
large width is configured to act as an evaporating portion of the
heat pipe.
4. The flat heat pipe with sectional differences according to claim
1, wherein the sectional difference portion having a relatively
small width is configured to act as a heat-transmitting portion of
the heat pipe.
5. The flat heat pipe with sectional differences according to claim
1, wherein each of the grooves is formed with sintered powder.
6. A method for manufacturing a flat heat pipe with sectional
differences, including steps of: a) draw-forming a tubular hollow
pipe body, the pipe body having one outer diameter, forming a
plurality of grooves on an inner wall of the pipe body; b) making
the pipe body to have a plurality of outer diameters along its
length to thereby form a plurality of tubular sectional difference
portions on the pipe body; c) degassing the interior of the pipe
body into vacuum and sealing both ends of the pipe body; and (d)
pressing the respective sectional difference portions of the pipe
body into flat.
7. The method according to claim 6, wherein any one or part of the
sectional difference portions is narrowed by a pipe-narrowing
process in the step b).
8. The method according to claim 7, wherein an un-narrowed part of
the sectional difference portions is widened by a pipe-widening
process.
9. The method according to claim 6, wherein any one or part of the
sectional difference portions is widened by a pipe-widening process
in the step b).
10. The method according to claim 9, wherein an un-widened part of
the sectional difference portions is narrowed by a pipe-narrowing
process.
11. The method according to claim 6, wherein after the pipe body is
formed with the plurality of sectional difference portions in the
step b), metal powder is filled in each groove of the pipe body,
the metal powder is sintered to become sintered powder.
Description
BACKGROUND OF THE INVENTION
[0001] 1. Field of the Invention
[0002] The present invention relates to a heat pipe and a method
for manufacturing the same, and in particular to a flat heat pipe
with sectional differences in its width direction and a method for
manufacturing the same.
[0003] 2. Description of Prior Art
[0004] When the traditional tubular heat pipe is to be applied in
an electronic element for heat dissipation or applied in a place
with a limited height, the tubular heat pipe has to be made flat.
In addition, after the tubular heat pipe is pressed flat, the flat
surface is brought into thermal contact with a heat source in a
surface-to-surface contact relationship. The thus-formed contact
area is larger, so that the heat transfer efficiency of the flat
heat pipe is better.
[0005] After the traditional tubular heat pipe is sealed at its
ends, since the wick structure disposed in the heat pipe is often
formed of sintered powder or metallic meshes, such a wick structure
will make the flattening process of the heat pipe unsmooth.
Further, since the outer diameter of the traditional tubular heat
pipe is smaller, usually from 6 mm to 8 mm or so, the width of the
thus-formed flat heat pipe is not large enough to cover the surface
of a desired heat-generating element completely.
[0006] In view of the above, the present Inventor proposes a novel
and reasonable structure based on his expert knowledge and
deliberate researches.
SUMMARY OF THE INVENTION
[0007] The present invention is to provide a flat heat pipe with
sectional differences and a method for manufacturing the same. The
inner wall of a pipe body of the tubular heat pipe is formed with a
plurality of grooves in which a wick structure is formed. Further,
the pipe body is integrally formed with a plurality of sectional
difference portions having different outer diameters respectively.
By this structure, when the pipe body is pressed flat, the wick
structure formed in the grooves will not suffer damage. Further,
since the pitches between the grooves in the respective sectional
difference portions are different, an evaporating portion and a
heat-transmitting portion of the heat pipe can be reinforced based
on practical demands.
[0008] The present invention provides a flat heat pipe with
sectional differences, which has a flat hollow pipe body. A working
fluid is sealed in the pipe body. The pipe body is provided along
its length with a plurality of flat sectional difference portions
having different widths. A connecting portion is formed between the
sectional difference portions. The inner wall of the pipe body is
formed with a plurality of grooves. The pitch between the grooves
in the sectional difference portion of a relatively large width is
larger than the pitch between the grooves in the sectional
difference portion of a relatively small width.
[0009] The present invention provides a method for manufacturing a
flat heat pipe with sectional differences, including steps of:
[0010] a) draw-forming a tubular hollow pipe body, the pipe body
having one outer diameter, forming a plurality of grooves on an
inner wall of the pipe body;
[0011] b) making the pipe body to have a plurality of outer
diameters along its length to thereby form a plurality of tubular
sectional difference portions on the pipe body;
[0012] c) degassing the interior of the pipe body into vacuum and
sealing both ends of the pipe body; and
[0013] (d) pressing the respective sectional difference portions of
the pipe body into flat.
BRIEF DESCRIPTION OF DRAWING
[0014] FIG. 1 is a schematic view of showing the external
appearance of the flat heat pipe of the present invention;
[0015] FIG. 2 is a cross-sectional view taken along the line 2-2 in
FIG. 1;
[0016] FIG. 3 is a cross-sectional view taken along the line 3-3 in
FIG. 1;
[0017] FIG. 4 is a flow chart showing the method for manufacturing
the flat heat pipe of the present invention;
[0018] FIG. 5 is a schematic view showing the pipe body formed in a
step S1 of FIG. 4;
[0019] FIG. 6 is a schematic view showing the pipe body formed in a
step S2 of FIG. 4;
[0020] FIG. 7 is a schematic view showing the pipe body formed in a
step S3 of FIG. 4; and
[0021] FIG. 8 is a schematic view showing the internal structure of
the flat heat pipe with sectional differences according to another
embodiment of the present invention.
DETAILED DESCRIPTION OF THE INVENTION
[0022] In order to make the Examiner to better understand the
characteristics and technical contents of the present invention,
the detailed description relating thereto will be made with
reference to the accompanying drawings. However, the drawings are
illustrative only, but not used to limit the scope of the present
invention.
[0023] Please refer to FIG. 1, which is a schematic view showing
the external appearance of the flat heat pipe with sectional
differences according to the present invention. The present
invention provides a flat heat pipe with sectional differences and
a method for manufacturing the same. The flat heat pipe of the
present invention has a flat hollow pipe body 1. A working fluid
(not shown) is sealed in the pipe body 1. The pipe body 1 is
provided along its length with at least two flat sectional
difference portions 11, 12 of different widths. A sectional
difference is formed between the sectional difference portions 11,
12 in the width direction of the pipe body 1. A connecting portion
13 is integrally formed between the sectional difference portions
11, 12. Please also refer to FIGS. 2 and 3. The inner wall of the
pipe body 1 is formed with a plurality of grooves 10, 10'. The
pitch between the grooves 10 in the section difference portion 11
of a relatively large width is larger than the pitch between the
grooves 10' in the sectional difference portion 12 of a relatively
small width.
[0024] According to the above, in the present embodiment of the
present invention, the sectional difference portions 11, 12 include
a first sectional difference portion 11 and a second sectional
difference portion 12. The width of the first sectional difference
portion 11 is larger than the width of the second sectional
difference portion 12. Thus, it can be seen from FIGS. 2 and 3
that, the pitch between the grooves 10 of the first sectional
difference portion 11 is larger than the pitch between the grooves
10' of the second sectional difference portion 12.
[0025] Please refer to FIG. 4 again. The present invention further
includes a method for manufacturing a flat heat pipe with sectional
differences, which includes the following steps.
[0026] Please also refer to FIG. 5. In the step 51 of FIG. 4, a
hollow tubular pipe body 1 is formed by a draw-forming process. The
pipe body 1 has only one outer diameter, that is, the pipe body 1
has equal outer diameter throughout its length. During the
draw-forming process of the pipe body 1, the inner wall of the pipe
body 1 is formed with a plurality of grooves 10.
[0027] Please also refer to FIG. 6. In the step S2 of FIG. 4, a
pipe body 1 is made to have at least two outer diameters, whereby
the pipe body 1 is formed with a plurality of tubular sectional
difference portions 11 and 12. Any one or a part of the sectional
difference portions 11 and 12 is widen or narrowed by a
pipe-widening process or a pipe-narrowing process. In this way, the
pipe body 1 can be formed along its length with two sectional
difference portions 11, 12 of different outer diameters. In the
present embodiment of the present invention, the second sectional
difference portion 12 is narrowed by a pipe-narrowing process, so
that the outer diameter of the second sectional difference portion
12 is smaller than the outer diameter of the first sectional
difference portion 11. In this way, the pipe body 1 can be formed
with two sectional difference portions 11 and 12 of difference
diameters. Of course, the first sectional difference portion 11 may
be widened by a pipe-widening process. In other words, in the
present step, not only any one or part of the second sectional
difference portion 12 is narrowed, but also the first sectional
difference portion 11 may be widened. Alternatively, any one or
part of the first sectional difference portion 11 may be widened,
and the un-widened second sectional difference portion 12 is
narrowed. In this way, the difference between the outer diameters
of the first and second sectional difference portions 11, 12 can be
increased.
[0028] Please also refer to FIG. 7. In the step S3 of FIG. 4, the
interior of the pipe body is degassed to become vacuum and its both
ends are sealed. More specifically, a working fluid is sealed in
the pipe body, and the gas (usually the gas unable to be condensed)
is drawn out to become vacuum. The open end(s) of the pipe body is
pressed and sealed. Alternatively, the open end(s) of the pipe body
is sealed by a welding process.
[0029] In the step S1 of FIG. 4, finally, the sectional difference
portions 11, 12 of the pipe body 1 are pressed to become flat, so
that the flat heat pipe with sectional differences as shown in FIG.
1 can be obtained.
[0030] Further, as shown in FIG. 8, after the pipe body 1 is formed
with the plurality of sectional difference portions 11 and 12 in
the step S2, the grooves 10 in the pipe body 1 are filled with
metal powder. After subjected to a sintering process, the metal
powder in the grooves 10 becomes sintered powder, thereby
increasing its capillary force.
[0031] With the above constituents and steps, the flat heat pipe
with sectional differences and the method for manufacturing the
same can be obtained.
[0032] Thus, according to the present invention, since the pitch
between the grooves 10 in the sectional difference portion 11 of a
relatively large width is larger than the pitch between the grooves
10' in the sectional difference 12 of a relatively small width, the
sectional difference portion 11 having a relatively large width is
configured to act as an evaporating portion of the heat pipe, which
will be brought into thermal contact with a heat source. Such a
flat structure has an increased surface area, so that the contact
area with the heat source is also increased to dissipate more heat
per unit time. Further, the larger surface area can generate a
better heat-dissipating effect. The larger pitch between the
grooves 10 helps to store greater amount of working fluid and to
perform a heat-exchanging effect. The sectional difference portion
12 having a relatively small width is configured to act as a
heat-transmitting portion of the heat pipe because the
heat-transmitting portion does not need to have a large contact
area. On the other hand, such a heat-transmitting portion may have
to be bent or curved to dodge surrounding elements. Further,
heat-dissipating pieces (not shown) may be connected to the
heat-transmitting portion to increase its effect of condensing the
vapor-phase working fluid flowing there through. Moreover, the
dense grooves 10' in the sectional difference portion 12 helps to
increase the capillary force therein. Thus, the sectional
difference portion 12 having a relatively small width is suitable
for the heat-transmitting portion. Therefore, the evaporating
portion and the heat-transmitting portion of the flat heat pipe can
be reinforced based on the practical demands.
[0033] According to the above, the present invention really
achieves the desired objects and solves the problems in prior art.
Further, the present invention demonstrates novelty and inventive
steps, which conforms to the requirements for an invention
patient.
[0034] Although the present invention has been described with
reference to the foregoing preferred embodiments, it will be
understood that the invention is not limited to the details
thereof. Various equivalent variations and modifications can still
occur to those skilled in this art in view of the teachings of the
present invention. Thus, all such variations and equivalent
modifications are also embraced within the scope of the invention
as defined in the appended claims.
* * * * *