U.S. patent application number 12/465648 was filed with the patent office on 2010-06-10 for heat spreader and heat dissipation device using same.
This patent application is currently assigned to FU ZHUN PRECISION INDUSTRY (SHEN ZHEN) CO., LTD.. Invention is credited to SHUN-YUAN JAN, XIAN-MIN JIN, JER-HAUR KUO, FANG-XIANG YU.
Application Number | 20100139888 12/465648 |
Document ID | / |
Family ID | 42229771 |
Filed Date | 2010-06-10 |
United States Patent
Application |
20100139888 |
Kind Code |
A1 |
JIN; XIAN-MIN ; et
al. |
June 10, 2010 |
HEAT SPREADER AND HEAT DISSIPATION DEVICE USING SAME
Abstract
A heat dissipation fan includes a fan frame, a bearing assembly,
a stator and a rotor. The fan frame includes a base and a central
tube. The central tube includes an open top end and an open bottom
end. The base defines a receiving concave at a bottom surface
thereof. The receiving concave communicates with the central hole.
A top wall is formed by the base over the concave. A sidewall is
formed between the top wall and the bottom surface of the base and
surrounds the concave. A plurality of first locking units extend
from the top wall into the receiving concave. The bearing assembly
includes an oil sealing cover for sealing the open bottom end of
the central tube. The oil sealing cover includes a plurality of
second locking units which are detachably interlocked with the
first locking units to mount the oil sealing cover to the base.
Inventors: |
JIN; XIAN-MIN; (Shenzhen
City, CN) ; YU; FANG-XIANG; (Shenzhen City, CN)
; JAN; SHUN-YUAN; (Tu-Cheng, TW) ; KUO;
JER-HAUR; (Tu-Cheng, TW) |
Correspondence
Address: |
PCE INDUSTRY, INC.;ATT. Steven Reiss
288 SOUTH MAYO AVENUE
CITY OF INDUSTRY
CA
91789
US
|
Assignee: |
FU ZHUN PRECISION INDUSTRY (SHEN
ZHEN) CO., LTD.
Shenzhen City
CN
FOXCONN TECHNOLOGY CO., LTD.
Tu-Cheng
TW
|
Family ID: |
42229771 |
Appl. No.: |
12/465648 |
Filed: |
May 14, 2009 |
Current U.S.
Class: |
165/80.3 ;
165/185 |
Current CPC
Class: |
H01L 23/427 20130101;
H01L 23/467 20130101; F28F 3/12 20130101; H01L 2924/0002 20130101;
H01L 2924/0002 20130101; H01L 2924/00 20130101; F28F 3/02
20130101 |
Class at
Publication: |
165/80.3 ;
165/185 |
International
Class: |
F28F 13/00 20060101
F28F013/00; F28F 7/00 20060101 F28F007/00 |
Foreign Application Data
Date |
Code |
Application Number |
Dec 8, 2008 |
CN |
200810306050.7 |
Claims
1. A heat dissipation device comprising: a heat spreader comprising
a main plate and an end cover coupling to one lateral side of the
main plate, the main plate defining a plurality of parallel through
holes therein, each of the through holes having an open end facing
the lateral side of the main plate, a plurality of wick structures
being respectively disposed in the through holes, the end cover
sealing the open ends of the through holes to form a plurality of
hermetical channels in the spreader, a working medium being
contained in each of the channels; and a plurality of fins arranged
on a surface of the main plate perpendicular to the lateral
side.
2. The heat dissipation device of claim 1, wherein each of the
through holes has a second open end facing another lateral side of
the main plate opposite to the lateral side, the heat spreader
further comprising a second end cover located at the another
lateral side of the main plate for sealing the second open ends of
the through holes, each of the end covers comprising a plurality of
connecting portions received in the open ends of the through holes,
respectively.
3. The heat dissipation device of claim 2, wherein each of the
connecting portions has a diameter lager than a diameter of each of
the through holes, the end covers connected with the main plate by
interference fit between the connecting portions and the open ends
of the through holes.
4. The heat dissipation device of claim 2, wherein each of the
connecting portions has a diameter smaller than a diameter of each
of the through holes, the end covers connected with the main plate
by soldering filled between each connecting portion and an inner
surface of the main plate at the open ends of a corresponding
through hole.
5. The heat dissipation device of claim 2, wherein the main plate
defines a first and a second receiving grooves at the two lateral
sides thereof, respectively, each of the through holes
communicating the first receiving groove with the second receiving
groove, each of the end covers comprising a sealed portion received
in a corresponding one of the first and the second receiving
grooves, the connecting portions extending from the sealed portions
into the through holes.
6. The heat dissipation device of claim 5, wherein each of the
receiving grooves is rectangular, the through holes are arranged in
the main plate side by side, a height of the receiving groove is
larger than a diameter of each of the through holes, and a length
of the receiving groove is larger than a width of an occupying area
of the through holes.
7. The heat dissipation device of claim 1, wherein each of the fins
comprises a plate-shaped main body extending upwardly from the top
surface of the main plate, the main body being parallel to the
through holes.
8. The heat dissipation device of claim 1, wherein each of the fins
comprises a main body and a flange extending perpendicularly from a
bottom end of the main body to a neighboring fin, the flanges
cooperatively forming a planar surface contacting the top surface
of the main plate.
9. A heat spreader comprising: a main plate defining a plurality of
parallel through holes in an interior thereof, each of the through
holes communicated with two opposite lateral sides of the main
plate; two end covers located at the two lateral sides of the main
plate, each of the end covers comprising a plurality of connecting
portions received in distal ends of the through holes for sealing
the through holes; a plurality of wick structures disposed in the
through holes and contacting an inner surface of the main plate;
and a working medium being contained in each of the through
holes.
10. The heat spreader of claim 9, wherein the main plate defines
two receiving grooves at the two lateral sides of the main plate,
respectively, distal ends of each through hole communicated with
the two receiving grooves respectively, each of the end covers
comprising a sealed portion received in a corresponding receiving
groove.
11. The heat spreader of claim 10, wherein the connecting portions
extend from one surface of the sealed portion facing the main plate
towards the distal ends of the through holes, respectively.
12. The heat spreader of claim 10, wherein each of the receiving
grooves is rectangular, each of the sealed portions has a shape and
a size corresponding to those of the each of the receiving grooves.
Description
BACKGROUND
[0001] 1. Technical Field
[0002] The present disclosure relates to heat spreaders, and more
particularly to a heat spreader for transferring heat of a heat
generating electronic component and a heat dissipation device using
same.
[0003] 2. Description of Related Art
[0004] Nowadays, heat sinks are used in electronic products for
dissipating heat generated by electronic components such as CPUs.
Typically, a heat spreader made of metals having a high thermal
conductivity is configured for distributing and transferring heat
from the CPU to the heat sink. The heat spreader is arranged to
have an intimate contact with the electronic component and absorbs
heat therefrom.
[0005] However, the electronic components are made to be more
powerful while occupying a smaller size. Thus, a contacting area
between the electronic component and the heat spreader is decreased
as the size of the electronic component decreases. Therefore, a
heat flux density between a contacting portion of the heat spreader
and other portions of the heat spreader is increased. As the CPU
operates faster and faster, and, therefore generates larger and
larger amount of heat, the conventional heat spreader, which
transfers heat via heat conduction means, cannot transfer heat to
the heat sink uniformly to meet the increased heat dissipating
requirement of the CPU.
[0006] For the foregoing reasons, therefore, there is a need in the
art for a heat spreader which overcomes the above-mentioned
problems.
BRIEF DESCRIPTION OF THE DRAWINGS
[0007] FIG. 1 is an assembled, isometric view of a heat dissipation
device in accordance with a first embodiment.
[0008] FIG. 2 is an exploded view of the heat dissipation device of
FIG. 1.
[0009] FIG. 3 is a cross-section of the heat dissipation device of
FIG. 1, taken along line III-III thereof.
[0010] FIG. 4 is an exploded view of a heat spreader of a heat
dissipation device in accordance with a second embodiment.
[0011] FIG. 5 is a cross-section of a heat dissipation device in
accordance with a third embodiment.
DETAILED DESCRIPTION
[0012] Reference will now be made to the drawing figures to
describe the present heat dissipation device in detail.
[0013] Referring to FIGS. 1 and 2, a heat dissipation device 10 in
accordance with a first embodiment of the disclosure is shown. The
heat dissipation device 10 is mounted on a heat generating
electronic component 40 such as a CPU (central processing unit), a
North Bridge chip or an LED (light emitting diode) to dissipate
heat therefrom. The heat dissipation device 10 includes a heat
spreader 20 and a heat sink 30 mounted on the heat spreader 20.
[0014] The heat spreader 20 has a flat type configuration and is
rectangular shaped when viewed from above. The heat spreader 20
includes a main plate 21 and a first and a second end covers 23
located at front and rear sides of the main plate 21, respectively.
The main plate 21 has a flat rectangular bottom surface 212 (FIG.
3) contacting the electronic component 40 and an opposite top
surface 211. The main plate 21 defines a plurality of through holes
25 in an interior thereof. The through holes 25 are parallel to and
spaced from each other. The through holes 25 are arranged side by
side along a left-to-right direction of the main plate 21. Each of
the through holes 25 has a circular cross section and includes an
evaporator section at a middle portion of the main plate 21 and two
condenser sections adjacent to the front and rear sides of the main
plate 21, respectively. A first and a second receiving grooves 24
are defined at the front and rear sides of the main plate 21,
respectively. The receiving grooves 24 are concaved inwardly from
the front and rear sides of the main plate 21. Each of the through
holes 25 extends horizontally along a front-to-rear direction of
the main plate 21 to communicate the first receiving groove 24 with
the second receiving groove 24. An annular wick structure 26 (FIG.
3) is disposed in each of the through holes 25 and contacts an
inner surface of the main plate 21. The wick structures 26 are
selected from a porous structure such as grooves, sintered powder,
screen mesh, or bundles of fiber to provide capillary force in the
through holes 25. The through holes 25 can be provided with
different kinds of wick structure therein, according to the actual
heat dissipation requirement. Each of the receiving grooves 24 is
rectangular and elongated. A diameter of each of the through holes
25 is smaller than a height of the receiving grooves 24. A width of
an occupying region of the through holes 25 along the left-to-right
direction of the main plate 21 is smaller than a length of the
receiving groove 24.
[0015] Each of the end covers 23 includes a rectangular sealed
portion 231 and a plurality of connecting portions 233 extending
horizontally from an inner side surface of the sealed portion 231
towards the main plate 21. The sealed portion 231 of each end cover
23 has a size substantially equal to a size of each of the first
and the second receiving grooves 24 of the main plate 21. Each of
the connecting portions 233 is column. The connecting portions 233
of each of the end covers 23 are paralleled to and spaced from each
other. The connecting portions 233 are arranged along a
left-to-right direction of the inner side surface of the sealed
portion 231 and face the through holes 25 correspondingly. Number
of the connecting portions 233 of each of the end covers 23 equals
to the number of the through holes 25 of the main plate 21. A
diameter of each of the connecting portions 233 is slightly larger
than the diameter of each of the through holes 25. The connecting
portions 233 of the end covers 23 can be inserted into distal ends
of the through holes 25, respectively. Thus, the end covers 23
connect with the main plate 21 by interference fit of the
connecting portions 233 in the through holes 25. Accordingly, the
distal ends of each through hole 25 are sealed by the connecting
portions 233 of the end covers 23, respectively.
[0016] Alternatively, the diameter of each of the connecting
portions 233 can be slightly smaller than the diameter of each of
the through holes 25. Solders can be sprayed on an outer surface of
connecting portions 233 or the inner surface of the main plate 21
at the distal ends of the through holes 25, thus the end covers 23
and the main plate 21 can be connected with each other by
soldering. A plurality of hermetical channels are thus formed in
the interior of the main plate 21 by the through holes 25. The wick
structures 26 are layered on the inner surfaces of the hermetically
channels. Subsequently, the hermetically channels are evacuated and
then injected with working medium 29 therein which has a lower
boiling point and is compatible with the wick structures 26. The
working medium 29 can be selected from a liquid such as water,
alcohol, or methanol.
[0017] The heat sink 30 includes a plurality of parallel fins 31
arranged side by side on the top surface 211 of the base plate 21.
Each of the fins 31 extends along the same direction as the through
holes 25. That is, each of the fins 31 extends along the
front-to-rear direction of the main plate 21. Referring to FIG. 3,
each of the fins 31 includes a plate-shaped main body 311 and a
flange 312 extending perpendicularly from a bottom end of the main
body 311 to a neighboring fin 31. The flanges 312 cooperatively
form a planar bottom surface at a bottom side of the heat sink 30
for increasing a contacting area between the top surface 211 of the
main plate 21 and the heat sink 30.
[0018] In operation of the heat dissipation device 10, the
electronic component 40 is disposed under and has an intimate
contact with a central portion of the bottom surface 212 of the
main plate 21. A substantially rectangular shaped heating area 27
is formed at the central portion of the bottom surface 212 of the
heat spreader 20, absorbing heat from the electronic component 40.
A spreading area 28 surrounding the heating area 27 is thus formed
at an outer periphery of the heat spreader 20 for transferring the
heat to the heat sink 30 and dissipating the heat to surrounding
environment.
[0019] The working medium 29 contained in the evaporator sections
of the through holes 25 corresponding to the heating area 27
vaporizes due to the heat absorbed from the electronic component
40. The vapor then spreads to fill the hermetically channels of the
main plate 21, and wherever the vapor comes into contact with the
condenser sections of the through holes 25 corresponding to the
spreading area 28 of the main plate 21, it releases its latent heat
of vaporization and condenses. Simultaneously, the vapor moves
upwardly to transfer the heat to the fins 31 above the heating area
27. The heat is therefore spread on the entire heat spreader 20
quickly and uniformly, and thus can be evenly transferred to each
fin 31 of the heat sink 30 for dissipating to surrounding
environment. The condensate returns to the heating area 27 due to
the capillary forces generated by the wick structures 26.
Thereafter, the condensate continues to vaporize and condense,
thereby removing the heat generated by the electronic component
40.
[0020] In the present heat spreader 20, the main plate 21 defines
the plurality of through holes 25 containing working fluid and wick
structure 26 therein, the heat generated by the heat generating
electronic component 40 can be quickly absorbed by the working
medium 29 contained in through holes 25, since the lowest heat
resistance between the electronic component 40 and the main plate
21 and the large contacting areas between wick structures 26 and
the main plate 21. The through holes 25 and the wick structures 26
thereof help the working medium 29 contained in the main plate 21
to horizontally move in the main plate 21 from the heating area 27
of the heat spreader 20 to the spreading area 28 due to their low
heat resistance. The through holes 25 and the wick structures 26
thereof also help the heat transfer to the fins 31 on the top
surface 211 of the heat spreader 20 with low heat resistance, and
therefore mounts of heat generated by the electronic component 40
is quickly and effectively transferred to different portions of the
heat sink 30 far from the electronic component 40. This increases
the heat transfer capability of the heat spreader 20 greatly, and
thereby increasing the heat dissipation efficiency of the heat
dissipation device 10.
[0021] FIG. 4 is an exploded view of a heat spreader 20a in
accordance with a second embodiment of the disclosure, differing
from the previous heat spreader 20 only in that a main plate 21a
defines one receiving groove 24 at a front side and forms a close
surface at a rear side, through holes 25a defined in an interior of
the main plate 21a each have an open end communicated with the
receiving groove 24 and a close end corresponding to the close rear
surface, and accordingly only one end cover 23 is in included at
the front side of the main plate 21a for sealing the open ends of
the through holes 25a.
[0022] FIG. 5 is a cross-section of a heat dissipation device 10b
in accordance with a third embodiment of the disclosure, differing
from the previous heat dissipation device 10 only in that the fins
31b and the main plate 21b of the heat spreader 20b are integrally
formed by extrusion, and each of the fins 31b includes a
plate-shaped main body 311b extending upwardly and perpendicularly
from a top surface 211b of the main plate 21b. In the present heat
dissipation device 10b, lower heat resistance between the main
plate 21b and the fins 31b can be obtained, and thus heat transfer
to the fins 31b on the top surface 211b of the main plate 21b can
be very quick for further increasing the heat dissipation
efficiency of the heat dissipation device 10b.
[0023] It is to be understood, however, that even though numerous
characteristics and advantages of the disclosure have been set
forth in the foregoing description, together with details of the
structure and function 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 invention to the full extent indicated by the
broad general meaning of the terms in which the appended claims are
expressed.
* * * * *