U.S. patent application number 11/012958 was filed with the patent office on 2006-02-16 for heat sink electronic components.
This patent application is currently assigned to HON HAI Precision Industry CO., LTD.. Invention is credited to Chun-Chi Chen, Meng Fu, Chi Liang, Shi-Wen Zhou.
Application Number | 20060032617 11/012958 |
Document ID | / |
Family ID | 35043971 |
Filed Date | 2006-02-16 |
United States Patent
Application |
20060032617 |
Kind Code |
A1 |
Chen; Chun-Chi ; et
al. |
February 16, 2006 |
Heat sink electronic components
Abstract
A heat sink for electronic component includes a base, a first
heat dissipation member coupled to the base, heat pipes embedded in
the base and a second heat dissipation member coupled to the base.
The base is made of a first metal material and includes a heat
absorbing portion having a bottom surface for contacting with the
electronic component and a heat conductive portion extending from a
top surface of heat absorbing portion. The first heat dissipation
member is made of a second metal material and coupled to the heat
absorbing portion of the base. The second heat dissipation member
is made of second metal material and coupled to the heat conductive
portion of the base. The first metal material differs from and has
higher heat conductivity than the second metal material.
Inventors: |
Chen; Chun-Chi; (Tu-Cheng,
TW) ; Zhou; Shi-Wen; (Shenzhen, CN) ; Liang;
Chi; (Shenzhen, CN) ; Fu; Meng; (Shenzhen,
CN) |
Correspondence
Address: |
MORRIS MANNING & MARTIN LLP
1600 ATLANTA FINANCIAL CENTER
3343 PEACHTREE ROAD, NE
ATLANTA
GA
30326-1044
US
|
Assignee: |
HON HAI Precision Industry CO.,
LTD.
Tu-Cheng City
TW
|
Family ID: |
35043971 |
Appl. No.: |
11/012958 |
Filed: |
December 14, 2004 |
Current U.S.
Class: |
165/104.33 ;
257/E23.088 |
Current CPC
Class: |
H01L 2924/0002 20130101;
F28F 3/02 20130101; H01L 2924/00 20130101; H01L 23/427 20130101;
F28D 15/0275 20130101; H01L 2924/0002 20130101 |
Class at
Publication: |
165/104.33 |
International
Class: |
F28D 15/00 20060101
F28D015/00 |
Foreign Application Data
Date |
Code |
Application Number |
Aug 14, 2004 |
CN |
200420083051.7 |
Claims
1. A heat sink for an electronic component comprising: a base made
of a first metal material and including a heat absorbing portion
which has a bottom surface for contacting with the electronic
component and a heat conductive portion extending from a top
surface of the heat absorbing portion; a first heat dissipation
member thermally coupled to the heat absorbing portion of the base
and made of a second metal material; and a second heat dissipation
member thermally coupled to the heat conductive portion of the
base; wherein the first metal material differs from the second
metal and has a higher heat conductivity than the second metal
material.
2. The heat sink as claimed in claim 1, wherein the first metal
material is copper, and the second metal material is aluminum.
3. The heat sink as claimed in claim 1, wherein the heat conductive
portion is perpendicular to the heat absorbing portion.
4. The heat sink as claimed in claim 1, further comprising at least
a heat pipe thermally coupling the heat absorbing portion to the
heat conductive portion.
5. The heat sink as claimed in claim 4, wherein the second heat
dissipation member comprises a plurality of fins perpendicular to
the heat conductive portion.
6. The heat sink as claimed in claim 1, wherein a plurality of fins
for increasing heat dissipation surface is formed on the first heat
dissipation member.
7. The heat sink as claimed in claim 1, further comprising a cover
body covering the second heat dissipation member.
8. A heat sink for a heat generating member comprising: a base
comprising a heat absorbing portion having a bottom surface for
contacting with the heat generating member and a heat conductive
portion extending from the heat absorbing portion away from the
heat generating member; a first heat dissipation member attached to
the heat absorbing portion and stretching in a plane parallel to
the bottom surface of the heat absorbing portion; at least one heat
pipe embedded in the base for transferring heat from the heat
absorbing portion to the heat conductive portion; and a second heat
dissipating member comprising a plurality of fins each contacting
with the heat conductive portion.
9. The heat sink as claimed in claim 8, wherein the base is made of
a first metal material with a first heat conductivity, and the
first heat dissipation member is made of a second metal material
with a second heat conductivity higher than the first metal
material.
10. The heat sink as claimed in claim 9, wherein the first metal
material is copper, and the second metal material is aluminum.
11. The heat sink as claimed in claim 8, wherein the base has an
inverted-T structure that comprises a horizontal heat absorbing
portion and an erect heat conductive portion.
12. The heat sink as claimed in claim 11, wherein the base defined
at least a groove extending from the heat absorbing portion to the
heat conductive portion for receiving said heat pipes.
13. The heat sink as claimed in claim 8, wherein a plurality of
fins is formed on the first heat dissipation member.
14. The heat sink as claimed in claim 8, further comprising a cover
body covering the second heat dissipation member.
15. The heat sink as claimed in claim 8, wherein each fin of the
second heat dissipation contacts with said heat pipe.
16. A heat dissipation assembly for a heat generating member
comprising: a base disposed next to said heat generating member and
having a heat absorbing portion to thermally contact with said heat
generating member; a first heat dissipation member thermally
contacting with said heat absorbing portion of said base and
defining a first heat dissipation area extending from said heat
absorbing portion of said base; and a second heat dissipation
member thermally contacting with a portion of said base other than
said heat absorbing portion and defining a second heat dissipation
area extending from said portion of said base and independent from
said first heat dissipation area.
17. The heat dissipation assembly as claimed in claim 16, wherein
said base is made by material different from at least one of said
first and second heat dissipation member.
18. The heat dissipation assembly as claimed in claim 16, wherein
said heat absorbing portion defines a surface to contact with said
heat generating member and said first dissipation area of said
first dissipation member is disposed by surrounding said
surface.
19. The heat dissipation assembly as claimed in claim 16, wherein
said portion of said base extends vertically from said heat
absorbing portion away from said heat generating member and said
second dissipation area of said second dissipation member is
disposed by surrounding said portion.
20. The heat dissipation assembly as claimed in claim 16, further
comprising a heat pipe attached to said base and extending from
said heat absorbing portion to said portion of said base, said heat
pipe having thermal contact with said base and at least one of said
first and second heat dissipation member.
Description
BACKGROUND OF THE INVENTION
[0001] 1. Technical Field
[0002] The present invention generally relates to a heat sink for
cooling heat-generating components, and particularly to a heat sink
for efficiently cooling electronic components.
[0003] 2. Related Art
[0004] In recent electronic apparatus, integrated circuit devices,
microprocessors and other related computer components are becoming
more and more powerful with increasing of capabilities, which
results in increasing of packaging densities and amounts of heat
generated by these components. Sizes of Packaged units and
integrated circuit devices are decreasing, while the amount of heat
generated by these components per unit volume, mass, surface area
or any other such metric is increasing. On the other hand, the heat
generating components including LSI (large scale integrated
circuit) are assembled in high packaging density on printed circuit
boards and many these printed circuit boards are inserted into a
cabinet with a small spacing. Therefore, the heat generation rate
within each electronic apparatus is strikingly increased. In recent
designs, the space for packaging each heat sink has become
narrower, and the heat radiation within the electronic apparatus
has become an extremely difficult problem.
[0005] Heat sinks are devices attached directly to electronic
components or other heat sources to enhance heat dissipation
thereof. A heat sink is generally designed with a base for
contacting with the heat source to absorb heat therefrom, and a
plurality of fins or other like element affixed on the base for
dissipating heat transferred from the base. The heat sink is often
designed with a greater volume, and made of a higher conductivity
material for a large capability of heat dissipation.
[0006] A conventional heat sink is made of aluminum. In order to
acquire a satisfied capability of heat dissipation, a great volume
of the heat sink is needed, which conflicts with the narrower and
narrower usable space. As an improvement of capability of heat
dissipation, copper preferred.
[0007] Another consideration when designing a heat sink is weight.
Although copper-based heat sinks may be preferred over aluminum due
to better heat transfer results, copper is a heavier material. A
whole copper heat sink will show a passive deflect on a printed
circuit board (PCB). The deflection of the PCB can cause component
damage as well as damage to the PCB traces and solder pads.
[0008] In order to dissipate continuously and effectively the heat
generated by the electronic apparatus, various designs bring out. A
typical heat sink is disclosed in Taiwan patent publication No.
326939. The heat sink comprises a T-shaped base made of a single
material and a heat dissipation member coupled with the base. The
heat generated by a heat source is absorbed by the base and then
transferred to the heat dissipation member and emitted to ambient
air. The above-mentioned problems exist in the same way. There is
not an all-sided settlement whether the heat sink is made of single
aluminum or single cooper. An improvement is needed.
[0009] Along with increasing of the heat generated, phase change
type products with great high heat conductivity, such as heat
pipes, have been widely applied to heat sinks for enhancing the
performance thereof. Heat pipes are hermetically sealed chambers,
inside of which has a wicking structure and fills with working
fluid. According to the principles of phase change heat transfer,
thermal energy enters an evaporative section of the heat pipe and
vaporizes the working fluid. The fluid moves through the heat pipe
to an area of lower temperature, and then condenses. After the
vapor condenses, the wicking structure draws the liquid back to the
evaporative section by capillary action within the wick. The cycle
is repeated continuously. Because of the rapid transport capability
of the vapor, heat pipes have a very high effective thermal
conductivity over large distances.
SUMMARY OF THE INVENTION
[0010] Accordingly, an object of the present invention is to
provide a heat sink for an electronic component, with an excellent
heat dissipating performance and a smaller weightiness and
volume.
[0011] It is accordingly another object of the present invention to
provide a heat sink incorporating heat pipes for heat dissipation
efficiency of the heat sink.
[0012] To achieve the above-mentioned objects, a heat sink is
applied. The heat sink comprises a base including a heat absorbing
portion having a bottom surface contacting with the electronic
component and a heat conductive portion extending from the surface
opposite to the bottom surface of heat absorbing portion. A first
heat dissipation member is coupled to the conductive portion of the
base.
[0013] As a specified embodiment, the base is made of a first metal
material, and the first heat dissipation member is made of a second
metal material. The first metal material differs from and has a
higher conductivity than the second metal material. Further, the
first metal material is copper and the second material is
aluminum.
[0014] And as another specified embodiment, at least a heat pipe is
embedded into the base and thermal couples the heat absorbing
portion to the heat conductive portion. At this circumstance, it is
not limited to that the second metal material differs from the
first metal material. The base with heat pipe embedded therein has
similarly higher equivalent heat conductivity than the first heat
dissipation made of single metal.
[0015] The foregoing and other objects and features of the
invention will become apparent from the following description of
preferred embodiments of the invention with reference to the
accompanying drawings, in which:
BRIEF DESCRIPTION OF THE DRAWINGS
[0016] FIG. 1 is an exploded perspective view of the heat sink as a
preferred embodiment of the present invention;
[0017] FIG. 2 is an exploded perspective view illustrating the base
and the first heat dissipation member in FIG. 1; and
[0018] FIG. 3 is a fully assembled view of FIG. 1.
DETAILED DESCRIPTION OF A PREFERRED EMBODIMENT
[0019] In the following detailed description of the embodiments,
reference is made to the accompanying drawings that illustrate
embodiment of the present invention and its practice. FIG. 1 is an
exploded perspective view of a heat dissipation assembly like a
heat sink 1 for a heat generating member like an electronic
component (not shown) in accordance with the present invention. The
heat sink 1 comprises an inverted T-shaped base 10, a first heat
dissipation member 20, several heat pipes 30, a second heat
dissipation member 40 and a cover body 50.
[0020] Referring to FIG. 2, the base 10 is made of a first metal
material with a first conductivity, copper being preferred, and
comprises a horizontal flat heat absorbing portion 12 which has a
bottom surface for contacting with the electronic component and a
top surface opposite to the bottom surface, and a heat conductive
portion 14 extending upwardly and perpendicularly from the middle
of the top surface of the heat absorbing portion 12. The heat
conductive portion 14 has two opposite side surfaces. Two pairs of
grooves 16 are defined in the top surface of the heat absorbing
potion 12 and extend to side faces of the heat conductive portion
14 to therefore become form of erect "L". That is, each groove 16
comprises a level portion 16A extending on the top surface of the
heat absorbing portion 12 and an erect portion 16B extending on one
side surface of the heat conductive portion 14. To optimize the
effect of heat transfer and meet the requirement of fabrication,
the two pairs of grooves are arrayed in a stagger manner on
opposite side surfaces of the heat conductive portion 14 and the
top surface of the heat absorbing portion 12.
[0021] Referring to FIG. 1 again, each heat pipe 30 has an L shape
and comprises a horizontal evaporative section 32 and a
condensative section 34 extending perpendicularly from one end of
the evaporative section 32. Each heat pipe 30 is so fitted into a
corresponding groove 16 that the evaporative section 32 is disposed
in the level portion 16A of the groove 16 and the condensative
section 34 is disposed in the erect portion 16B of the groove
16.
[0022] The first heat dissipation member 20 is a flat metal plate
defining an opening 22 therein. The heat absorbing portion 12 of
the base 10 is fittingly received in the opening 22 of the first
heat dissipation member 20 to thereby combine the base 10 with the
first dissipation member 20. The first heat dissipation member 20
extends in a plane parallel to the bottom face of the base 10. It
is preferable that the bottom face of the first heat dissipation
member 20 is coplanar with the bottom face of the base 10. A
plurality of fins 24 is formed on the top surface of the first heat
dissipation member 20 by and not limited to extrusion or soldering.
A significant characteristic of the first heat dissipation member
20 is that it is made of a second metal material differing from the
first metal material, aluminum being referred, with a second heat
conductivity lower than the first conductivity. Generally, the
second metal material is lighter than the first metal material.
[0023] The second heat dissipation member 40 comprises a group of
fins 42, generally made of aluminum, parallel to each other.
Pluralities of passages are formed between adjacent fins 42 and the
heat conductive portion 14 of the base 10. The second heat
dissipation member 40 is attached to the heat conductive portion 14
in a arrangement that the fins 42 are attached perpendicularly to
the side face of the heat conductive portion 14 of the base 10, and
thermally contact with the condensative sections 34 of the heat
pipes 30, by means of soldering, paste or the like.
[0024] Please refer to FIG. 3 together with FIG. 1, the cover body
50 has an inverted U shape and is fixed to the first heat
dissipation member 20 by screws. The cover body 50 covers the
second heat dissipation member 40 so as to construct the passages
between the fins 42 into ducts with two open ends. When a fan (not
shown) is mounted to one side of the second heat dissipation member
40 and orthogonal to the fins 42, the air flow provided by the fan
travels through the ducts so as to carry the heat accumulated at
the fins 42 out.
[0025] In the above description of the embodiments of the present
invention, the connection between the base 10 and the first heat
dissipation member 20, between the heat pipes 30 and the base 10,
and between the base 10 and the second heat dissipation member 40
can be accomplished in any known ways familiar to those of ordinary
skill in the art, such as highly thermally conductive epoxy,
soldering or only mechanical engagement.
[0026] It is obvious that the heat pipes 30 are not necessary for
the heat sink 1 under a condition that the first metal material
differs from and has a higher conductivity than the second metal
material. In the same way, it is not necessary that the first metal
material differs from and has a higher conductivity than the second
metal material when the heat pipes are applied. It is optimal that
both of those are provided. Due to significantly high heat
conductivity of the base with embedded heat pipe, the heat absorbed
by the heat absorbing portion 12 is quickly transferred to the heat
conductive portion 14 and there is a slight temperature difference
between the heat absorbing portion 12 and the heat conductive
portion 14. As a result, the heat absorbing portion 12 and the heat
conductive portion 14 has a nearly uniform temperature
distribution, which avails to improve efficiency of heat
dissipation of the heat sink 1.
[0027] The heat sink 1 has not a great volume and weight due to use
of two different metal material with different heat conductivity
and density. At the same time, the heat sink 1 minimizes its volume
and weight and increases heat dissipation performance. This effect
is further strengthened by the use of heat pipes 30.
[0028] It is recognized that the invention may be susceptible to
various other modifications and alternative constructions in view
of this disclosure. Although the invention has been shown and
described in detail herein by a preferred embodiment and certain
alternatives, it should be understood that there is no intention of
limiting the invention strictly to this. But rather it is the
intention to cover all such other modifications and alternative
constructions falling within the spirit and scope of the invention
as defined in the appended claims.
* * * * *