U.S. patent application number 12/238441 was filed with the patent office on 2010-04-01 for heat dissipation device.
This patent application is currently assigned to FU ZHUN PRECISION INDUSTRY (SHEN ZHEN) CO., LTD.. Invention is credited to RUI-HUA CHEN, XUE-WEN PENG.
Application Number | 20100079941 12/238441 |
Document ID | / |
Family ID | 42057245 |
Filed Date | 2010-04-01 |
United States Patent
Application |
20100079941 |
Kind Code |
A1 |
PENG; XUE-WEN ; et
al. |
April 1, 2010 |
HEAT DISSIPATION DEVICE
Abstract
A heat dissipation device includes a first heat sink, a second
heat sink juxtaposed with the first heat sink and a plurality of
heat pipes thermally connecting the first heat sink and the second
heat sink. The first heat sink includes a plate-like spreader used
for contacting with a first electric component and a honeycomb-like
first fin unit thermally attached on the spreader. The spreader is
a flat heat pipe. The heat pipes each include a flat plate-shaped
evaporating section sandwiched between the spreader and the first
fin unit of the first heat sink and a condensing section extending
in the second heat sink. Due to a provision of the honeycomb-like
first fin unit, the heat dissipation area of the first heat sink
greatly increases.
Inventors: |
PENG; XUE-WEN; (Shenzhen
City, CN) ; CHEN; RUI-HUA; (Shenzhen City,
CN) |
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: |
42057245 |
Appl. No.: |
12/238441 |
Filed: |
September 26, 2008 |
Current U.S.
Class: |
361/679.52 |
Current CPC
Class: |
H01L 23/467 20130101;
H01L 2924/00 20130101; H01L 23/427 20130101; H01L 2924/0002
20130101; H01L 2924/0002 20130101 |
Class at
Publication: |
361/679.52 |
International
Class: |
H05K 7/20 20060101
H05K007/20 |
Claims
1. A heat dissipation device, comprising: a first heat sink
comprising a plate-shaped spreader which is a flat heat pipe with a
work fluid filled therein, adapted for contacting with a first
heat-generating electronic component, and a honeycomb-shaped first
fin unit thermally attached to the spreader; a second heat sink
juxtaposed with the first heat sink; and a plurality of heat pipes
thermally connecting the first heat sink and the second heat sink,
the heat pipes each comprising a flat plate-shaped evaporating
section sandwiched between the spreader and the first fin unit of
the first heat sink, a condensing section extending in the second
heat sink and a connecting section formed between corresponding
evaporating and condensing sections, the connecting section
comprising a first portion close to the evaporating section and a
second portion close to the condensing section, the first portion
being located at a plane different from that of the second
portion.
2. The heat dissipation device as claimed in claim 1, wherein the
first portion of the connecting section is perpendicular to the
evaporating section of the each heat pipe.
3. The heat dissipation device as claimed in claim 2, wherein the
first portion of the connecting section of the each heat pipe is
parallel to a lateral side of the first and second heat sinks.
4. The heat dissipation device as claimed in claim 2, wherein the
first fin unit of the first heat sink defines a receiving groove in
a bottom thereof and the evaporating sections of the heat pipes are
received in the receiving groove.
5. The heat dissipation device as claimed in claim 4, wherein top
surfaces of the evaporating sections of the heat pipes are coplanar
with a bottom surface of the first fin unit of the first heat
sink.
6. The heat dissipation device as claimed in claim 5, wherein the
second heat sink comprises a honeycomb-shaped second fin unit and
the condensing sections of the heat pipes are extended in a top
portion of the second fin unit of the second heat sink.
7. The heat dissipation device as claimed in claim 6, wherein the
second heat sink comprises a base and the second fin unit is
thermally attached to the base.
8. The heat dissipation device as claimed in claim 1, wherein the
first heat sink further comprises a frame and the spreader is
thermally attached to the frame.
9. The heat dissipation device as claimed in claim 8, wherein the
frame defines a cutout through a side thereof and the spreader has
a sealed tube extending outwardly from a side thereof, the sealed
tube being extended through the cutout of the frame when the
spreader is mounted on the frame.
Description
BACKGROUND OF THE INVENTION
[0001] 1. Field of the Invention
[0002] The present invention relates generally to heat dissipation
devices, and more particularly to a heat dissipation device having
excellent heat dissipating efficiency.
[0003] 2. Description of Related Art
[0004] Computer electronic components, such as central processing
units (CPUs), generate great amounts of heat during normal
operation thereof. If the heat is not properly dissipated, it can
deteriorate an operational stability of the electronic components
and damage associated electronic devices. Thus the heat must be
removed quickly to ensure normal operation of these electronic
components. A heat dissipation device is often attached to a top
surface of a CPU to remove heat therefrom.
[0005] Conventionally, a heat dissipation device attached to a CPU
includes a solid base, a plurality of fins arranged on the base,
and a plurality of heat pipes extending in the base and the fins. A
plurality of grooves is defined in the base, and a plurality of
holes is defined in the fins. Each heat pipe has a bent
configuration and includes an evaporating section received in a
corresponding groove of the base and a condensing section extending
from the evaporating section. The condensing section is inserted in
a corresponding hole of the fins. However, the heat originating
from the CPU is directly absorbed by a middle part of the base and
cannot quickly spread to other parts of the base. This results in
an overheating of the middle part of the base, while the other
parts of the base have a lower temperature relative to the middle
part. The fins on the other parts of the base away from the middle
part are not efficiently used. The heat dissipating efficiency of
the heat sink needs to be improved through sufficient use of all of
the fins on the base. Additionally, the fins of a conventional heat
sink which have the fins extending upwardly and perpendicularly
from the base thereof, do not have a sufficiently large
heat-dissipation area to remove heat from the CPU; thus, the heat
dissipating efficiency of the heat dissipation device is poor.
[0006] What is needed, therefore, is a heat dissipation device with
an enhanced heat dissipation performance.
SUMMARY OF THE INVENTION
[0007] According to a preferred embodiment of the present
invention, a heat dissipation device includes a first heat sink, a
second heat sink juxtaposed with the first heat sink, and a pair of
heat pipes thermally connecting the first and second heat sinks.
The first and second heat sinks are for attaching to first and
second CPUs, respectively. The first heat sink includes a
plate-shaped spreader thermally attached to the first CPU and a
honeycomb-like first fin unit thermally attached on the spreader.
The heat pipes each include an evaporating section received in the
first fin unit and tightly sandwiched between the spreader and the
first fin unit and a condensing section extending in the second
heat sink. The spreader is a flat heat pipe. Due to a provision of
the honeycomb-like first fin unit, the heat-dissipation area of the
first heat sink is greatly increased and the heat dissipating
efficiency of the heat dissipation device is accordingly
enhanced.
[0008] Other advantages and novel features of the present invention
will become more apparent from the following detailed description
when taken in conjunction with the accompanying drawings.
BRIEF DESCRIPTION OF THE DRAWINGS
[0009] Many aspects of the present apparatus 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 apparatus. Moreover, in the drawings, like reference
numerals designate corresponding parts throughout the several
views.
[0010] FIG. 1 is an assembled, isometric view of a heat dissipation
device in accordance with a preferred embodiment of the present
invention.
[0011] FIG. 2 is an exploded, isometric view of the heat
dissipation device in FIG. 1.
[0012] FIG. 3 is a front view of a first fin unit of the heat
dissipation device in FIG. 1.
DETAILED DESCRIPTION OF THE INVENTION
[0013] Referring to FIGS. 1-3, a heat dissipation device in
accordance with a preferred embodiment of the present invention
comprises a first heat sink 10, a second heat sink 20 juxtaposed
with the first heat sink 10 and a pair of heat pipes 30 thermally
connecting the first and second heat sinks 10, 20 together. The
first and second heat sinks 10, 20 are adapted for removing heat
from first and second heat-generating electronic components such as
a first and second CPUs 52, 54 mounted on a print circuit board 50
and spaced from each other.
[0014] The first heat sink 10 comprises a rectangular frame 12, a
plate-shaped spreader 14 thermally attached on the frame 12 by
soldering and a first fin unit 16 soldered on a top surface of the
spreader 14. The frame 12 defines four through holes 120 in
alignment with four fixing holes 510 defined in the print circuit
board 50 surrounding the first CPU 52, for extension of fasteners
80 therethrough to secure the frame 12 to the print circuit board
50. A cutout 122 is defined through a middle portion of a short
side of the frame 12. The spreader 14 is substantially a
rectangular flattened heat pipe, having a lighter weight and better
heat transferring capability than a solid metallic plate such as a
copper plate with an equal volume. The spreader 14 defines a cavity
(not shown) therein and contains working fluid in the cavity. The
working fluid has phase change when it works. A sealed tube 140
extends outwardly and horizontally from a short lateral side of the
spreader 14 through the cutout 122 of the frame 12, when the
spreader 14 is mounted on the frame 12. The first fin unit 16 is a
honeycomb-like structure and formed by stacking formed metal sheets
with high heat conductivity such as formed aluminum or copper
sheets, wherein each formed metal sheet has a hexagonal cross
section. An air passage 160 is defined in each formed metal sheet,
extending from a front side to a rear side of the first fin unit
16. Understandably, the shape of the cross sections of the air
passages 160 can be other shapes in an alternative embodiment. A
receiving groove 162 with a rectangular cross-section is defined in
a bottom of the first fin unit 16 and parallel to the short lateral
sides of the first fin unit 16. The receiving groove 160 is
constructed for receiving the heat pipes 30 therein.
[0015] The second heat sink 20 comprises a rectangular base 22 and
a second fin unit 24 thermally attached on a top surface of the
base 22 by soldering. Understandably, the base 22 can be a vapor
chamber with work fluid filled therein in an alternative
embodiment. In the present embodiment, the base 22 is a thin plate
made of copper or copper alloy. The base 22 defines four mounting
holes 220 in four corners thereof, for extension of the fasteners
80 therethrough to mount the base 22 on the second CPU 54 mounted
on the print circuit board 50. The second fin unit 24 is also a
honeycomb-like structure and formed by stacking formed aluminum or
copper sheets each with a hexagonal cross section. The second fin
unit 24 also defines a plurality of air passages (not labeled) in
the second fin unit 24 and parallel to the air passages 160 of the
first fin unit 16 of the first heat sink 10. The second fin unit 24
has a height much larger than that of the first fin unit 16 of the
first heat sink 10. A pair of receiving holes 240 with circular
cross sections are defined in a top portion of the second fin unit
24 and spaced from each other, for accommodating the heat pipes 30
therein.
[0016] Each of the heat pipes 30 has a flat-shaped evaporating
section 32, a round condensing section 34 and a connecting section
36 formed between the evaporating section 32 and the condensing
section 34. The evaporating section 32 has a flat top surface (not
labeled) and a flat bottom surface (not labeled) opposite to the
flat top surface, for providing a larger contacting area, when the
evaporating sections 32 of the heat pipes 30 are received in the
receiving groove 162 and thermally attached to the bottom surface
of the first fin unit 16 and the top surface of the spreader 14.
The flat bottom surfaces of the evaporating sections 32 of the heat
pipes 30 are attached and soldered on the top surface of a middle
of the spreader 14 of the first heat sink 10. The condensing
sections 34 are engagingly received in the receiving holes 240 of
the second fin unit 24 of the second heat sink 20. The connecting
sections 36 each comprises a first portion 360 located adjacent to
the evaporating sections 32 and a second portion 362 located
adjacent to the condensing sections 34. The first portions 360 of
the connecting sections 36 are juxtaposed to each other and
parallel to a front side of the first and second heat sinks 10, 20.
The first portions 360 are vertical to the evaporating sections 32
and located in a different plane from the second portions 362.
[0017] In operation, the heat dissipating device is mounted on the
print circuit board 50 by the fasteners 80 received in the through
holes 120, the mounting holes 220 and the fixing holes 510. The
spreader 14 of the first heat sink 10 is kept in intimate contact
with the first CPU 52 and absorbs heat generated by the first CPU
52. Due to the excellent heat conductivity of the spreader 14, the
heat from the first CPU 52 is quickly transferred to all parts of
the spreader 14, and then evenly and effectively distributed to the
whole first fin unit 16 and finally brought into ambient air. As
the heat pipes 30 are thermally connected with the first and second
heat sinks 10, 20, part of the heat from first CPU 52 is
transferred to the top portion of the second fin unit 24 of the
second heat sink 20 by the heat pipes 30. The base 22 of the second
heat sink 20 is thermally attached to the second CPU 54 and absorbs
heat generated by the first CPU 52. The heat from the second CPU 54
is transferred upwardly from the bottom portion to the top portion
of the second fin unit 24 of the second heat sink 20. Thus, the
heat from the part of the first CPU 52 and the second CPU 54 can be
evenly distributed in the second fin unit 24 to sufficiently use
every part of the second fin unit 24.
[0018] As each of the first and second fin units 16, 24 has a
honeycomb-like structure, a heat-dissipation area of each of the
first and second heat sinks 10, 20 is larger than that of a
conventional heat sink in a equal volume. Moreover, due to an
existence of the spreader 14, the heat from the first CPU 52 is
transferred to the spreader 14 and evenly distributed in the first
fin unit 16 via the spreader 14, thereby enabling the first fin
unit 16 to be effectively utilized.
[0019] It is believed that the present invention and its 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.
* * * * *