U.S. patent application number 12/392083 was filed with the patent office on 2010-04-29 for method for manufacturing a plate-type heat pipe.
This patent application is currently assigned to Foxconn Technology Co., Ltd.. Invention is credited to Chuen-Shu Hou.
Application Number | 20100101761 12/392083 |
Document ID | / |
Family ID | 42116359 |
Filed Date | 2010-04-29 |
United States Patent
Application |
20100101761 |
Kind Code |
A1 |
Hou; Chuen-Shu |
April 29, 2010 |
METHOD FOR MANUFACTURING A PLATE-TYPE HEAT PIPE
Abstract
A method for manufacturing a plate-type heat pipe including
providing a mold including a first cavity and a plurality of second
cavities located above and communicating with the first cavity and
depositing cores into the first cavity. First and second metal
powder are injected into the mold by using a double-mode injection
molder. The first metal powder securely adheres to the cores, and
the second metal powder fills up the first and second cavities
except the first metal powder located, thereby forming a green
piece. The cores are removed from the green piece to define
chambers in the green piece. The green piece is heated to obtain a
sintered product with an outer wall, fins extending from the outer
wall and a wick structure adhering inner surfaces of the outer
wall.
Inventors: |
Hou; Chuen-Shu; (Tu-Cheng,
TW) |
Correspondence
Address: |
PCE INDUSTRY, INC.;ATT. Steven Reiss
288 SOUTH MAYO AVENUE
CITY OF INDUSTRY
CA
91789
US
|
Assignee: |
Foxconn Technology Co.,
Ltd.
Tu-Cheng
TW
|
Family ID: |
42116359 |
Appl. No.: |
12/392083 |
Filed: |
February 24, 2009 |
Current U.S.
Class: |
165/104.26 ;
29/890.032 |
Current CPC
Class: |
F28D 15/0233 20130101;
Y10T 29/49353 20150115; B21D 53/02 20130101 |
Class at
Publication: |
165/104.26 ;
29/890.032 |
International
Class: |
F28D 15/00 20060101
F28D015/00; B21D 53/02 20060101 B21D053/02 |
Foreign Application Data
Date |
Code |
Application Number |
Oct 24, 2008 |
CN |
200810305183.2 |
Claims
1. A method for manufacturing a plate-type heat pipe comprising:
providing a mold comprising a first cavity and a plurality of
second cavities located at a top of the first cavity and
communicating with the first cavity; depositing a plurality of
cores into the first cavity of the mold; filling a first metal
powder and a second metal powder respectively into the first and
second cavities of the mold in such a manner that the first metal
powder covers the cores, and the second metal powder fills the
first and second cavities except the first metal powder located,
thereby forming a green piece; removing the cores from the green
piece to define a plurality of chambers therein; sintering the
green piece with the chambers defined therein to obtain a sintered
workpiece, wherein the sintered workpiece has an outer wall and a
plurality of fins extending upwardly from a top side of the outer
wall; vacuuming the chambers; injecting a working fluid into the
chambers via a port in the sintered workpiece; and sealing the port
of the sintered workpiece.
2. The method for manufacturing a plate-type heat pipe as in claim
1, the first and second metal powder are filled in the mold by
using a double-mode injection molder.
3. The method for manufacturing a plate-type heat pipe as in claim
1, wherein each of the second cavities of the mold has one of
following configurations: a cuboidal configuration, a cone-shaped
configuration, a round rod-shaped configuration, a rectangular
rod-shaped configuration, a rhombus rod-shaped configuration and a
circular frustum-shaped configuration, and the second cavities are
spaced from each other.
4. The method for manufacturing a plate-type heat pipe as in claim
3, wherein each of the second cavities has a configuration of a
rhombus rod-shaped configuration, the second cavities are arranged
in a matrix having a plurality of rows and columns, a space between
two neighboring second cavities of a same column is smaller than
that between two neighboring second cavities of a same row.
5. The method for manufacturing a plate-type heat pipe as in claim
1, wherein the second cavities of the mold are arranged in to a
matrix.
6. The method for manufacturing a plate-type heat pipe as in claim
1, wherein the first cavity of the mold is cuboidal.
7. The method for manufacturing a plate-type heat pipe as in claim
6, wherein the cores disposed in the first cavity of the mold are
spaced from each other.
8. The method for manufacturing a plate-type heat pipe as in claim
1, wherein a particle size of the first metal powder is larger than
that of the second metal powder.
9. The method for manufacturing a plate-type heat pipe as in claim
1, wherein each of the cores is made of one of a polymer material
and a waxy material.
10. The method for manufacturing a plate-type heat pipe as in claim
1, wherein each of the cores is removed from the green piece by one
of thermal cracking and chemical reaction.
11. A plate-type heat pipe comprising: a hermetic outer wall; a
plurality of spaced fins extending upwardly from a top surface of
the outer wall, wherein the outer wall and the fins are of a same
metal and integrally formed as a single piece; a wick structure
contacting with inner surfaces of the outer wall; at least a
chamber defined in the wick structure; and a working liquid
received in the at least a chamber.
12. The plate-type heat pipe as in claim 11, wherein a plurality of
spaced supporting poles is formed by the wick structure and located
between top and bottom ends of the outer wall.
13. The plate-type heat pipe as in claim 12, wherein the supporting
poles and the wick structure are porous.
14. The plate-type heat pipe as in claim 11, wherein each of the
fins has one of following configurations: a cuboidal configuration,
a cone-shaped configuration, a round rod-shaped configuration, a
rectangular rod-shaped configuration, a rhombus rod-shaped
configuration and a circular frustum-shaped configuration, and the
fins are spaced from each other.
15. The plate-type heat pipe as in claim 14, wherein each of the
fins has a configuration of a rhombus rod-shaped configuration, the
fins are arranged in a matrix having a plurality of rows and
columns, a space between two neighboring fins of a same column is
smaller than that between two neighboring fins of a same row.
Description
BACKGROUND OF THE INVENTION
[0001] 1. Field of the Invention
[0002] The disclosure relates to a method for manufacturing a
plate-type heat pipe, and more particularly to a method for
manufacturing a plate-type heat pipe which utilizes technologies of
metal injection molding and powder sintering.
[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 case formed by stamping a metal sheet to have an engaging plate
and a base plate defining a trough. A plurality of fins is welded
on a top surface of the engaging plate. The case contains working
fluid therein. A wick structure is laid on an inner wall of the
base plate and an inner wall of the engaging plate. The base plate
and the engaging plate are assembled together by welding. It is
difficult to precisely weld the base plate and the engaging plate
together, whereby the base plate and the engaging plate may not be
hermetically connected together, or the welding strength is not
sufficient to meet the required value. In addition, the welded
connection between the engaging plate and the fins has a thermal
resistance hindering a smooth and efficient heat transfer from the
engaging plate to the fins.
[0005] It is therefore desirable to provide a method for
manufacturing a plate-type heat pipe overcoming the shortcomings of
the conventional art.
BRIEF DESCRIPTION OF THE DRAWINGS
[0006] Many aspects of the present embodiments can be better
understood with reference to the following drawings. The components
in the drawings are not necessarily drawn to scale, the emphasis
instead being placed upon clearly illustrating the principles of
the present embodiments. Moreover, in the drawings, like reference
numerals designate corresponding parts throughout the several
views.
[0007] FIG. 1 is a cross-sectional view showing a mold for forming
a plate-type heat pipe in accordance with a first embodiment of the
disclosure.
[0008] FIG. 2 is a cross-sectional view of a green piece for
forming the plate-type heat pipe in accordance with the first
embodiment of the disclosure, wherein the green piece is formed by
and removed from the mold of FIG. 1.
[0009] FIG. 3 is a cross-sectional view of a plate-type heat pipe
in accordance with the first embodiment of the disclosure.
[0010] FIG. 4 is a cross-sectional view of a plate-type heat pipe
in accordance with a second embodiment of the disclosure.
[0011] FIG. 5 is a perspective view showing fins of a plate-type
heat pipe in accordance with a third embodiment of the
disclosure.
[0012] FIG. 6 is a perspective view showing fins of a plate-type
heat pipe in accordance with a fourth embodiment of the
disclosure.
[0013] FIG. 7 is a perspective view showing fins of a plate-type
heat pipe in accordance with a fifth embodiment of the
disclosure.
[0014] FIG. 8 is a perspective view showing fins of a plate-type
heat pipe in accordance with a sixth embodiment of the
disclosure.
[0015] FIG. 9 is a perspective view showing fins of a plate-type
heat pipe in accordance with a seventh embodiment of the
disclosure.
DETAILED DESCRIPTION OF THE INVENTION
[0016] Referring to FIGS. 1-3, a method for manufacturing a
plate-type heat pipe 10 in accordance with a first embodiment of
the disclosure will be explained in the following. Firstly, a mold
90 is provided. The mold 90 consists of an upper half (not labeled)
and a lower half (not labeled), wherein when the mold 90 is closed
as shown in FIG. 1, the mold 90 defines therein a large, cuboidal
first cavity 91 and a number of small, cuboidal second cavities 93
located at a top of the first cavity 91 and communicating with the
first cavity 91. The first and second cavities 91, 93 cooperatively
define a cavity which has structure and size corresponding to those
of the plate-type heat pipe 10.
[0017] Secondly, a plurality of spaced cores 30 of a material
releasable by thermal cracking reaction or chemical reaction is
deposited into the first cavity 91 of the mold 90. Each core 30 has
a cuboidal configuration and a number of pores therein. A web (not
shown) extends through the cores 30 to connect the cores 30
together as a single unit.
[0018] Thirdly, a first metal powder with particle diameter from 5
.mu.m to 90 .mu.m and a second metal powder with particle diameter
from 50 .mu.m to 150 .mu.m are respectively injected into the first
and second cavities 91, 93 of the mold 90 using two injection
systems with opposite injection directions. As a result, the second
metal powder covers the cores 30 and fills the pores of the cores
30, and the first metal powder fills the first and second cavities
91, 93 of the mold 90 except the second metal powder located,
thereby forming a green piece. The injection systems is in a
double-mode injection molder (not shown).
[0019] Fourthly, the cores 30 are removed from the green piece by
thermal cracking reaction or chemical reaction, thereby defining a
number of hollow, cuboidal chambers 15 in the green piece.
[0020] Finally, the green piece with the chambers 15 defined
therein undergoes a series of processes to become the plate-type
heat pipe 10. The green piece is disposed in a sintering oven and
sintered at a high temperature, whereby the first and second metal
powders are bound together to obtain a sintered workpiece. The
chambers 15 are vacuumed and filled with a working fluid (not
shown) such as water, alcohol, methanol, or the like, via a port in
the workpiece. Finally, the port in the workpiece is hermetically
sealed. As a result, the desired plate-type heat pipe 10 is
obtained and includes a tight, hermetic outer wall 11, a plurality
of cuboidal fins 13 extending upwardly from a top surface of a side
of the outer wall 11, and a wick structure 14 thermally contacting
with inner surfaces of the outer wall 11. The wick structure 14
includes a number of supporting poles 17 between top and bottom
ends of the outer wall 11 to enhance the strength of the plate-type
heat pipe 10. In this state, the outer wall 11 and the fins 13 are
made of the first metal powder, and the wick structure 14 including
the supporting poles 17 is made of the second metal powder.
[0021] Each of the cores 30 is comprised of a polymer or waxy
material. After the cores 30 are removed, the green piece defines
the chambers 15 to receive the working fluid (not shown) therein.
The supporting poles 17 and the wick structure 14 are porous and
communicate with each other, therefore the working fluid can
quickly flow from a top end of the wick structure 14 to a bottom
end of the wick structure 14 along lengthways directions of the
supporting poles 17. The fins 13 integrate with the outer wall 11
of the plate-type heat pipe 10. Thus, heat resistance between the
fins 13 and the outer wall 11 is significantly reduced relative to
the conventional plate-type heat pipe. The heat dissipation
efficiency of the plate-type heat pipe 10 is accordingly
improved.
[0022] Referring to FIG. 4, a plate-type heat pipe 20 is
manufactured using the method previously described. The plate-type
heat pipe 20 is similar to the plate-type heat pipe 10. Difference
between the plate-type heat pipes 10, 20 is that each of the
chambers 25 of the plate-type heat pipe 20 has a configuration
different from that of each of the chambers 15 of the plate-type
heat pipe 10. Each of the chambers 25 of the plate-type heat pipe
20 has a trapezoid cross section with a larger top side and a
smaller bottom side. Meanwhile, each chamber 15 of the plate-type
heat pipe 10 has a rectangular cross section. A configuration of
each of the chambers 25 is identical to that of each of the cores
for forming a corresponding chamber 25. Thus, the cores in this
embodiment each have a configuration of a trapezoid block.
[0023] Referring to FIG. 5, a top portion of the outer wall 31 and
fins 33 of a plate-type heat pipe 30 are shown. The plate-type heat
pipe 30 is manufactured using the method described in the first
embodiment. Difference between the plate-type heat pipes 10, 30 is
that a configuration of each of the fins 33 of the plate-type heat
pipe 30 is different from that of each of the fins 13 of the
plate-type heat pipe 10. In this embodiment, each of the fins 33
has a configuration of a cone. Bottom ends of the fins 33 each
having the largest area for a corresponding fin 33 can absorb heat
of the plate-type heat pipe 30 quickly.
[0024] Referring to FIG. 6, fins 43 of a plate-type heat pipe 40
are shown. The plate-type heat pipe 40 is manufactured using the
method described in the first embodiment. Difference between the
plate-type heat pipes 30, 40 is that the configuration of each of
the fins 33 of the plate-type heat pipe 30 is different from that
of each of the fins 43 of the plate-type heat pipe 40. In this
embodiment, each of the fins 43 has a configuration of a round
rod.
[0025] Referring to FIG. 7, fins 53 of a plate-type heat pipe 50
are shown. The plate-type heat pipe 50 is manufactured using the
method described in the first embodiment. Difference between the
plate-type heat pipes 30, 50 is that the configuration of each of
the fins 33 of the plate-type heat pipe 30 is different from that
of each of the fins 53 of the plate-type heat pipe 50. In this
embodiment, each of the fins 53 has a configuration of a
rectangular rod. The fins 53 are arranged in a matrix on a top
portion of the outer wall.
[0026] Referring to FIG. 8, fins 63 of a plate-type heat pipe 60
are shown. The plate-type heat pipe 60 is manufactured using the
method described in the first embodiment. Difference between the
plate-type heat pipes 50, 60 is that the configuration of each of
the fins 53 of the plate-type heat pipe 50 is different from that
of each of the fins 63 of the plate-type heat pipe 60. In this
embodiment, each of the fins 63 has a configuration of a rhombus
rod. The fins 63 are arranged into a matrix with a plurality of
rows and columns. Two neighboring fins 63 of a same column is
spaced a distance smaller than that between two neighboring fins 63
of a same row.
[0027] Referring to FIG. 9, fins 73 of a plate-type heat pipe 70
are shown. The plate-type heat pipe 70 is manufactured using the
method described in the first embodiment. Difference between the
plate-type heat pipes 30, 70 is that the configuration of each of
the fins 33 of the plate-type heat pipe 30 is different from that
of each of the fins 73 of the plate-type heat pipe 70. In this
embodiment, each of the fins 73 has a configuration of a circular
frustum. Bottom end is larger than top end of each of the fins
73.
[0028] In this disclosure, configuration and size of each of the
fins are decided by those of each of the second cavities 93 of the
mold 90. As long as the configuration and size of the second cavity
93 of the mold 90 are changed, various plate-type heat pipes with
various fins can be obtained. Similarly, structure and size of the
outer wall 11, the wick structure 14 and the supporting poles 17
can be varied by changing structure and size of the first cavity 91
and the cores 30.
[0029] It is believed that the present embodiments and their
advantages will be understood from the foregoing description, and
it will be apparent that various changes may be made thereto
without departing from the spirit and scope of the invention or
sacrificing all of its material advantages, the examples
hereinbefore described merely being preferred or exemplary
embodiments of the invention.
* * * * *