U.S. patent application number 13/455717 was filed with the patent office on 2012-10-04 for heat sink.
This patent application is currently assigned to FURUKAWA ELECTRIC CO., LTD.. Invention is credited to Shinichi Furumoto, Shinichi ITO, Kenya Kawabata.
Application Number | 20120247735 13/455717 |
Document ID | / |
Family ID | 44506770 |
Filed Date | 2012-10-04 |
United States Patent
Application |
20120247735 |
Kind Code |
A1 |
ITO; Shinichi ; et
al. |
October 4, 2012 |
HEAT SINK
Abstract
The heat sink has a first heat transfer plate member that has
one surface thermally connected to a heat generating component and
is thermally connected to a first heat dissipating fin section
having thin plate fins; a second heat transfer plate member that
has one surface thermally connected to a second heat dissipating
fin section having thin plate fins; a heat pipe section that is
provided between an opposite surface of the first heat transfer
plate member and an opposite surface of the second heat transfer
plate member to be thermally connected thereto; and a heat transfer
block that is thermally connected to a side surface and an upper
surface of the heat pipe section and arranged to sandwich the heat
pipe section between the heat transfer block and the second heat
transfer plate member.
Inventors: |
ITO; Shinichi; (Tokyo,
JP) ; Kawabata; Kenya; (Tokyo, JP) ; Furumoto;
Shinichi; (Tokyo, JP) |
Assignee: |
FURUKAWA ELECTRIC CO., LTD.
Tokyo
JP
|
Family ID: |
44506770 |
Appl. No.: |
13/455717 |
Filed: |
April 25, 2012 |
Related U.S. Patent Documents
|
|
|
|
|
|
Application
Number |
Filing Date |
Patent Number |
|
|
PCT/JP2011/053827 |
Feb 22, 2011 |
|
|
|
13455717 |
|
|
|
|
Current U.S.
Class: |
165/104.21 |
Current CPC
Class: |
H01L 2924/0002 20130101;
H01L 23/4006 20130101; H01L 23/467 20130101; F28D 15/0275 20130101;
H01L 23/427 20130101; H01L 2924/00 20130101; H01L 2924/0002
20130101 |
Class at
Publication: |
165/104.21 |
International
Class: |
F28D 15/02 20060101
F28D015/02; F28F 7/00 20060101 F28F007/00 |
Foreign Application Data
Date |
Code |
Application Number |
Feb 26, 2010 |
JP |
2010-041467 |
Claims
1. A heat sink comprising: a first heat transfer plate member that
has one surface thermally connected to a heat generating component
and is thermally connected to a first heat dissipating fin section
having thin plate fins; a second heat transfer plate member that
has one surface thermally connected to a second heat dissipating
fin section having thin plate fins; a heat pipe section that is
provided between an opposite surface of the first heat transfer
plate member and an opposite surface of the second heat transfer
plate member to be thermally connected thereto; and a heat transfer
block that is thermally connected to a side surface and an upper
surface of the heat pipe section and arranged to sandwich the heat
pipe section between the heat transfer block and the second heat
transfer plate member.
2. The heat sink of claim 1, wherein the heat pipe section
comprises a plurality of heat pipes arranged side by side, at least
one of the heat pipes has a bent part, and the heat transfer block
is arranged to be thermally connected to side surfaces of outermost
heat pipes of the heat pipes section and upper surfaces of the heat
pipes.
3. The heat sink of claim 2, wherein the thin plate fins of the
first heat dissipating fin section are arranged in parallel to each
other and vertical to the surface of the first heat transfer plate
member and spaced from each other by a predetermined distance along
a width direction of the first heat transfer plate member at a
longitudinal end or over the surface of the first heat transfer
plate member.
4. The heat sink of claim 2, wherein the thin plate fins of the
second heat dissipating fin section are arranged in parallel to
each other and vertical to the surface of the second heat transfer
plate member and provided in a longitudinal direction and almost
over the surface of the second heat transfer plate member.
5. The heat sink of any one of claims 2 to 4, wherein each of the
heat pipes has a planular shape, the heat pipes are arranged in
parallel to each other and in contact with each other at least at
center thereof, and the bent part of the heat pipe is arranged
along an end of the second heat transfer plate member on which the
second heat dissipating fin section is arranged.
6. The heat sink of any one of claims 2 to 4, wherein each of the
heat pipes has a planular shape, the heat pipes are arranged in
parallel to each other and spaced from each other so as to be out
of contact from each other, and the bent part of the heat pipe is
arranged along an end of the second heat transfer plate member on
which the second heat dissipating fin section is arranged.
7. The heat sink of any one of claims 2 to 4, wherein one of the
heat pipes has straight shape, the heat pipe having straight shape
is arranged at center along a longitudinal direction of the second
heat transfer plate member, and other heat pipes are arranged
symmetric or asymmetric with respect to the heat pipe having
straight shape.
8. The heat sink of any one of claims 1 to 4, further comprising a
fixing portion for fixing the first heat transfer plate member and
the second heat transfer plate member at a peripheral part of the
heat sink while the heat pipe section is sandwiched between the
first heat transfer plate member and the second heat transfer plate
member.
Description
TECHNICAL FIELD
[0001] The present invention relates to a heat sink used for
cooling a component to be cooled in an electronic device, for
example, a heat-generating component such as CPU or MPU.
BACKGROUND ART
[0002] Recent years have seen significant advances in enhancing of
the performance and downsizing of various electric or electronic
devices such as personal computers. However, enhancement of the
performance of CPU, MPU and the like mounted on a notebook PC,
laptop and desktop PC causes an increase in heat generation.
Meanwhile, glowing demands for downsizing of the electric or
electronic devices require space saving in the electronic or
electronic devices.
[0003] Cooling of a higher-performance heat-generating component
such as CPU or MPU is always one of most important technical
problems. Besides, also in electric or electronic devices other
than computers, cooling of a higher-performance heat-generating
component or element becomes one of most important problems in view
of the demands for space saving in the electric or electronic
devices.
[0004] As a method of cooling an electronic component mounted in
the electric or electronic device, there is known a method of
directly cooling a component to be cooled by a cooler mounted on
the component to be cooled. As such a cooler mounted on the
component to be cooled, a heat sink is often used which is composed
of a base plate that is a plate member made of a material having
excellent heat conductivity such as copper or aluminum and thin
plate fins bonded to one surface of the base plate.
[0005] The above-mentioned method of dissipating heat of the
component to be cooled by the thin plate fins provided on the base
plate as a heat receiving section to receive heat from the
component to be cooled is generally used as a heat dissipater of an
electric device. In the conventional art, the heat sink (heat
dissipater) having the base plate and heat dissipating fins
provided on the base plate has been often made of extruded aluminum
with which the base plate and the heat dissipating fins are formed
integrally with each other, but now, copper is used to enhance the
heat dissipating performance.
[0006] The copper is excellent in heat conductivity. However, when
the base plate is large or the heat source is provided at one side
of the base plate, the heat spread effect (effect of heat transfer
to the entire part of the base plate) is not enough. In such a
case, the heat dissipating performance is improved by providing the
base plate with a heat pipe or a vapor chamber thereby to enhance
the spread effect of heat transfer to the base plate entirely and
enhance the heat dissipating performance.
[0007] The vapor chamber is high-cost and it is necessary to
include hole forming for mounting screws in first designing, which
causes a problem of loss of design flexibility. Besides, the case
of burying the heat pipes in the copper block, machining is
required such as cutting of grooves to bury the heat pipes, which
causes a problem of high cost. In order to solve these problems,
there is adopted a configuration in which heat pipes are sandwiched
between two plate members of the first plate member and the second
plate member. With this configuration, machining such as cutting
for fixing the heat pipes can be eliminated thereby to achieve cost
cutting. Further, a space is created around the heat pipes, which
leads to reduction in the weight of the base part and total weight
reduction.
[0008] Inside the heat pipe to move heat to a desired position, a
space is provided as a fluid path of working fluid. The working
fluid accommodated in the space is moved or phase-changed by
evaporating, compressing or the like so that the heat moves. That
is, at the heat absorbing side of the heat pipe, the working fluid
is evaporated by heat generated by the component to be cooled
transferred in a material of the heat pipe case, and its vapor is
moved to the heat dissipating side of the heat pipe. At the heat
dissipating side, the vapor of the working fluid is cooled and
returned to a liquid state again. In this way, the working fluid
returned into the liquid state moves to the heat absorbing side
again (back-flow). Such phase transformation and movement of the
working fluid causes heat movement.
CITATION LIST
Patent Literature
[0009] PL1: Japanese Patent Application Laid-Open No. 2009-198173
[0010] PL2: Japanese Patent Application Laid-Open No. H10
(1998)-107192
SUMMARY OF INVENTION
Technical Problem
[0011] When the heat pipes are sandwiched between the two plate
members that are the first plate member and the second plate
member, the ends of the heat pipes are spread in only one of the
width and longitudinal directions. However, at the part where the
plural heat pipes are in contact with the component to be cooled,
they are gathered at the center so as to move the heat efficiently
from the component to be cooled. Therefore, the space is created at
the side surfaces of the heat pipes and the heat cannot be
transferred sufficiently to the heat dissipating fins positioned
corresponding to the space, which causes a problem of insufficient
heat dissipation.
[0012] Further, if a metal block is buried in the entire part of
the heat sink for the purpose of transferring heat to the space at
the side surfaces of the heat pipes, the steps of cutting or
machining of the grooves for burying the heat pipes as described
above become complicated and the cost becomes problematically
high.
[0013] Accordingly, the present invention aims to provide a
high-performance heat sink that that has reduced machining
processes, light-weight and reduced costs and is capable of
improving heat dissipating performance.
Solution to Problem
[0014] The inventors of the present invention have studied
diligently to solve the conventional problems. As a result, they
have found that heat can be effectively dissipated in end
directions and side surface direction of the heat pipes by
transferring the heat via the heat pipes and the first plate member
at the ends of the heat pipes and thermally connecting the metal
block with excellent heat conductivity at the side surfaces of the
heat pipes, without need to use a metal block all over the heat
sink.
[0015] A first aspect of the present invention is a heat sink
comprising: a first heat transfer plate member that has one surface
thermally connected to a heat generating component and is thermally
connected to a first heat dissipating fin section having thin plate
fins; a second heat transfer plate member that has one surface
thermally connected to a second heat dissipating fin section having
thin plate fins; a heat pipe section that is provided between an
opposite surface of the first heat transfer plate member and an
opposite surface of the second heat transfer plate member to be
thermally connected thereto; and a heat transfer block that is
thermally connected to a side surface and an upper surface of the
heat pipe section and arranged to sandwich the heat pipe section
between the heat transfer block and the second heat transfer plate
member.
[0016] The heat sink according to a second aspect of the present
invention is characterized in that the heat pipe section comprises
a plurality of heat pipes that are arranged side by side (arranged
in a line), at least one of the heat pipes has a bent part, and the
heat transfer block is arranged to be thermally connected to side
surfaces of outermost heat pipes of the heat pipes and upper
surfaces of the heat pipes.
[0017] The heat sink according to a third aspect of the present
invention is characterized in that the thin plate fins of the first
heat dissipating fin section are arranged in parallel to each other
and vertical to the surface of the first heat transfer plate member
and spaced from each other by a predetermined distance along a
width direction of the first heat transfer plate member at a
longitudinal end or over the surface of the first heat transfer
plate member.
[0018] The heat sink according to a fourth aspect of the present
invention is characterized in that the thin plate fins of the
second heat dissipating fin section are arranged in parallel to
each other and vertical to the surface of the second heat transfer
plate member and provided in a longitudinal direction and almost
over the surface of the second heat transfer plate member.
[0019] The heat sink according to a fifth aspect of the present
invention is characterized in that each of the heat pipes has a
planular shape, the heat pipes are arranged in parallel to each
other and in contact with each other at least at center thereof,
and the bent part of the heat pipe is arranged along an end of the
second heat transfer plate member on which the second heat
dissipating fin section is arranged.
[0020] The heat sink according to a sixth aspect of the present
invention is characterized in that each of the heat pipes has a
planular shape, the heat pipes are arranged in parallel to each
other and spaced from each other so as to be out of contact from
each other, and the bent part of the heat pipe is arranged along an
end of the second heat transfer plate member on which the second
heat dissipating fin section is arranged.
[0021] The heat sink according to a seventh aspect of the present
invention is characterized in that one of the heat pipes, which is
arranged at a center along a longitudinal direction, is formed
linearly, and the heat pipes, except for the linear (straight) one
at the center, are arranged symmetric or asymmetric with respect to
the center and linear heat pipe arranged along a longitudinal
direction of the second heat transfer plate member.
[0022] The heat sink according to an eighth aspect of the present
invention is characterized by further comprising a fixing portion
for fixing the first heat transfer plate member and the second heat
transfer member at a peripheral part of the heat sink while the
heat pipe section is sandwiched between the first heat transfer
plate member and the second heat transfer plate member.
Advantageous Effects of Invention
[0023] According to the present invention, the heat sink is
configured to sandwich the heat pipes between two plate members
that are the first plate member and second plate member, and at
least one heat pipe is elongated in the longitudinal direction or
ends of plural heat pipes are spread in the longitudinal direction
and width direction, parts of the heat pipes in contact with a
component to be cooled are set at the center and the block having
excellent heat conductivity is arranged at a space formed at the
side surfaces of the heat pipes. With this structure, it is
possible to transfer the heat to the heat dissipating fins at the
position corresponding to the space sufficiently, thereby improving
the heat dissipating performance.
BRIEF DESCRIPTION OF DRAWINGS
[0024] FIG. 1 is a perspective view for explaining an aspect of a
heat sink of the present invention;
[0025] FIG. 2 is a view illustrating a back surface of the heat
sink according to the aspect of the present invention;
[0026] FIG. 3 is a top view of the heat sink according to the
aspect of the present invention;
[0027] FIG. 4 is a front view of the heat sink according to the
aspect of the present invention;
[0028] FIG. 5 is a lateral view of the heat sink according to the
aspect of the present invention;
[0029] FIG. 6 is a perspective view for explaining a heat sink
according to another aspect of the present invention;
[0030] FIG. 7 is a view illustrating a back surface of the heat
sink according to the other aspect of the present invention;
[0031] FIG. 8 is a top view of the heat sink according to the other
aspect of the present invention;
[0032] FIG. 9 is a front view of the heat sink according to the
other aspect of the present invention;
[0033] FIG. 10 is a lateral view of the heat sink according to the
other aspect of the present invention; and
[0034] FIGS. 11A, 11B and 11C are cross-sectional views for
explaining shapes of thin-plate fins of the present invention.
DESCRIPTION OF EMBODIMENTS
[0035] With reference to the drawings, description is made about a
heat sink according to the present invention.
[0036] The heat sink according to an aspect of the present
invention has a first heat transfer plate member that is thermally
connected at one surface to a heat generating component and also
thermally connected to a first heat dissipating fin section
composed of thin plate fins, a second heat transfer plate member
that is thermally connected at one surface to a second heat
dissipating fin section composed of thin plate fins, a heat pipe
section that is provided between the opposite surface of the first
heat transfer plate member and the opposite surface of the second
heat transfer plate member and thermally connected to them and a
heat transfer block that is thermally connected to an upper
surfaces and side surfaces of the heat pipe section and thermally
arranged so as to sandwich the heat pipe section between the heat
transfer block and the second heat transfer plate member.
[0037] FIG. 1 is a perspective view for explaining one aspect of
the heat sink of the present invention. FIG. 2 is a back-surface
view of the heat sink according to the one aspect of the present
invention. As illustrated in FIGS. 1 and 2, in the heat sink
illustrated in FIG. 1, two first heat transfer plate members 2-1,
2-2 and the heat transfer block 6 therebetween are provided
thermally connected to each other at the back surface side. The
heat transfer block 6 has end block parts 6-1, 6-2 that have
excellent heat transfer property and located at two side ends and a
heat receiving section 10 that connects the end block parts 6-1,
6-2 to each other and these are formed integrally. The end block
parts 6-1, 6-2 of the heat transfer block 6 have thick blocks and
the heat receiving section 10 that connects the end block parts to
each other is thinner than the end block parts 6-1, 6-2. A
relatively thinner plate connecting part is provided at the
position of the heat receiving section 10 of the heat transfer
block 6 and the heat receiving section 10 may be thermally bonded
thereon. The heat receiving section 10 is connected to the heat
generating component 20 (see FIG. 5) as a heat source.
[0038] As illustrated in FIG. 1, at the upper surface side of the
heat sink 1, the second heat transfer plate member 3 is provided so
as to face the heat transfer block 6 and the first heat transfer
plate members 2-1, 2-2. Between the first heat transfer plate
members 2-1, 2-2, the heat transfer block 6 and the second heat
transfer plate member 3, as indicated by the broken line in FIG. 2,
the heat pipe section comprising the plural heat pipes 7-1 to 7-5
is sandwiched therebetween and thermally connected thereto.
[0039] The upper and lower surfaces of the plural heat pipes 7-1 to
7-5 are in contact with the first heat transfer members 2-1, 2-2
and the heat receiving section 10 and thermally connected thereto.
Besides, each of the end block parts 6-1, 6-2 of the heat transfer
block 6 takes the shape of a thicker block, and the side surfaces
of the end block parts 6-1, 6-2 are in contact with side surfaces
of the outmost heat pipes 7-5, 7-1 and thermally connected
thereto.
[0040] At an end of the surface of the first heat transfer plate
member 2-1 (lower side in FIG. 1) that is out of contact with the
heat pipe, a first heat dissipating fin section 5 made of a
plurality of thin plate fins arranged at a predetermined pitch (fin
pitch) is thermally bonded to the first heat transfer plate member
2-1. Further, at the surface of the second heat transfer plate
member 3 (upper side in FIG. 1) out of contact with the heat pipe,
a second heat dissipating fin section 4 having plural thin plate
fins arranged at a predetermined fin pitch is thermally bonded to
the second heat transfer plate member 3.
[0041] The first heat dissipating fin section 5 bonded to the first
heat transfer plate member 2-1 and the second heat dissipating fin
section 4 bonded to the second heat transfer plate member 3 need
not to be formed integrally by extrusion and may be formed by
bonding plural fins to the heat transfer plate members at a desired
fin pitch.
[0042] As described above, between the heat receiving section 10 of
the heat transfer block 6 and the second heat transfer plate member
3, and between the first heat transfer plate members 2-1, 2-2 and
the second heat transfer plate member 3, the plural heat pipes 7-1
to 7-5 are sandwiched and thermally connected thereto. In the
aspect illustrated in FIG. 2, the five heat pipes are arranged side
by side. The shape of each heat pipe is preferably determined so as
to increase the contact surface between the second heat transfer
plate member 3 and the first heat transfer plate members 2-1, 2-2,
the heat transfer block 6. In the aspect of FIG. 2, it is
preferably planular (flat). The plural heat pipes 7-1 to 7-5 are
arranged in such a manner that the side surfaces are in contact
with each other with no space created therebetween at the position
between the heat transfer block 6 and the longitudinally center
part of the second heat transfer plate member 3.
[0043] Further, the plural heat pipes 7-1 to 7-5, except the heat
pipe 7-3 arranged at the center, are arranged so as to be spread in
the width direction of the first and second heat transfer plate
members at the side of the first heat dissipating fin section 5.
Particularly, an end of each of the heat pipes 7-2, 7-4 is bent at
right angles and extends in the width direction along the first
heat dissipating fin section. An end of each of the other heat
pipes 7-1, 7-5 is arranged in such a manner as to be spread in the
width direction of the second heat transfer plate member so that
the heat is transferred in the width direction of the heat transfer
plate member to the entire thin plate fins bonded to the second
heat transfer plate member 3.
[0044] The plural heat pipes 7-1 to 7-5 are thermally connected and
vertically sandwiched between the first heat transfer plate members
2-1, 2-2 and the second heat transfer plate member 3, except at the
position of the heat transfer block 6. Besides, the plural heat
pipes 7-1 to 7-5 are arranged with no space therebetween and in
contact with each other at the center parts thereof in the width
direction at the position of the heat transfer block 6 and they are
vertically sandwiched between and thermally connected to the second
heat transfer plate member 3 and the heat receiving section 10. The
outermost heat pipes 7-1, 7-5 are in contact at side surfaces
thereof with the end block parts 6-2, 6-1 of the heat transfer
block 6.
[0045] The surface of the heat receiving section 10 of the heat
transfer block 6 which is out of contact with the heat pipes 7-1 to
7-5 forms a heat receiving surface that is connected to the heat
source and the heat received by the heat receiving surface is
transferred to the heat pipes 7-1 to 7-5. With such a
configuration, the heat received by the heat receiving surface of
the heat receiving section 10 is transferred via the heat transfer
block 6 to the lower surfaces and side surfaces of the plural heat
pipes, thereby enabling efficient heat transfer to the heat pipes.
Here, the heat pipes are preferably arranged with side surfaces in
contact with each other, but they may be arranged in parallel out
of contact with a space therebetween. If the heat pipes are
arranged out of contact, the heat receiving section 10 is used to
transfer heat to each of the heat pipes.
[0046] In the aspect illustrated in FIG. 2, the end block parts
6-1, 6-2 of the heat transfer block 6 are arranged in contact with
side surfaces of the center straight parts of the outermost heat
pipes 7-1, 7-5 out of the heat pipes 7-1 to 7-5 arranged side by
side. The end block parts 6-1, 6-2 are connected by the heat
receiving section 10, which is arranged to be thermally connected
to the upper surfaces of the center parts of the heat pipes. That
is, as described above, the plural heat pipes 7-1 to 7-5 are
sandwiched between the first heat transfer plate members 2-1, 2-2
and the second heat transfer plate member 3 except at the position
of the heat transfer block 6 where they are sandwiched vertically
and horizontally between the heat transfer block 6 and the second
heat transfer plate member 3.
[0047] The upper surfaces of the end block parts 6-1 and 6-2 are
bonded to the second heat transfer plate member 3 by soldering or
the like. With this bonding, the heat from the heat receiving
section 10 can be transferred to the second heat transfer plate
member 3 efficiently. Here, the end block parts 6-1, 6-2 and the
second heat transfer plate member 3 are separate from the first
heat transfer members 2-1, 2-2 and the first heat transfer plate
members 2-1, 2-2 and the second heat transfer plate member 3 are
preferably fixed at the contact portion (for example, fixing parts
8 at the four corners) by solder bonding or the like. Besides, it
is also preferable that the first heat transfer plate members 2-1,
2-2 and the heat transfer block 6 are bonded at the contact portion
to each other by soldering.
[0048] Heat transferred to the heat receiving section 10 from the
heat generating component (heat source) is transferred from the
back surface of the heat receiving section 10 to the plural heat
pipes and diffused in the lateral direction to the end block parts
6-1, 6-2. That is, the heat transferred from the heat generating
component to the heat receiving section 10 is transferred to the
plural heat pipes 7-1 to 7-5 that are in direct contact with the
opposite surface to the heat receiving surface of the heat
receiving section 10. Then, the heat of the heat receiving section
10 is transferred to the end block parts 6-1, 6-2 and then to the
side surfaces of the heat pipes 7-1, 7-5. Further, the end block
parts 6-1, 6-2 and the heat pipes are thermally connected to the
second heat transfer plate member 3 and heat received by the heat
receiving section 10 is transferred via them to the almost entire
part of the second heat transfer plate member 3. Consequently, the
heat is transferred to the second heat dissipating fin section 4
having plural thin plate fins bonded to the almost entire part of
the upper surface of the second heat transfer plate member 3 and
dissipated from the heat dissipating fins to the outside of the
heat sink.
[0049] FIG. 3 is a top view of the heat sink according to one
aspect of the present invention. As illustrated in FIG. 3, thin
plate fins arranged in parallel at a predetermined fin pitch are
bonded to the almost entire part of one surface of the second heat
transfer plate member 3 (upper surface in FIG. 3) except fixing
parts 8 at four corners for fixing the first heat transfer plate
members 2-1, 2-2 and the second heat transfer plate member 2-3.
[0050] A first cover 9-1 is provided at one end of the second heat
dissipating fin section 4 and a second cover 9-2 is provided at
each side of the center part of the heat sink 10. The first and
second covers 9-1, 9-2 are used as covers when packaging the heat
sink of the present invention. Preferably they have cushioning
properties and may be made of porous resin or sponge, for
example.
[0051] FIG. 4 is a front view of the heat sink according to the one
aspect of the present invention. As illustrated in FIG. 4, at an
end of the opposite surface of the first heat transfer plate member
2-1 (lower side in FIG. 4) to the surface that is in contact with
the heat pipes, the first heat-dissipating fin section 5 composed
of thin plate fins is arranged to be thermally connected to the
end. The plural thin plate fins of the first heat dissipating fin
section are arranged along the longitudinal direction of the first
heat transfer plate members 2-1, 2-2.
[0052] A second heat dissipating fin section 4 composed of thin
plate fins is arranged as thermally connected to almost entire
surface of a surface of the second heat transfer plate member 3
(upper side in FIG. 4) opposite to the surface in contact with the
heat pipes. The plural thin plate fins of the second heat
dissipating fin section 4 are also arranged along the longitudinal
direction of the second heat transfer plate member 3.
[0053] The first heat dissipating fin section 5 and the second heat
dissipating fin section 4 are formed at a desired fin pitch on the
first heat transfer plate members 2-1, 2-2 and the second heat
transfer plate member 3, respectively. Between the first heat
transfer plate members 2-1, 2-2 and the second heat transfer plate
member 3, a plurality of heat pipes 7-1 to 7-5 arranged side by
side each other are sandwiched as thermally connected thereto.
[0054] Around the center part of the second heat transfer plate
member 3 in the longitudinal direction, the plural heat pipes 7-1
to 7-5 are arranged in contact with each other with no space
therebetween. The center part of the plural heat pipes is thermally
connected to the heat transfer block 6 having excellent heat
transfer performance. In the heat transfer block 6, the heat
receiving section 10 at the center part and both-sides end block
parts 6-1, 6-2 made of metal having excellent heat transfer
performance are formed integrally. Heat transferred from the
heat-generating component (heat source) to the heat receiving
section 10 of the heat transfer block 6 as a heat receiving surface
is transferred to the plural heat pipes 7-1, 7-2, 7-3, 7-4, 7-5 and
end block parts 6-1, 6-2. The heat is then, transferred to the
almost entire area in the vertical and horizontal directions of the
second heat transfer plate member 3 by the plural heat pipes 7-1 to
7-5 and end block parts 6-1, 6-2.
[0055] FIG. 5 is a lateral view of the heat sink illustrated in
FIG. 1. At an end of the surface (lower side in FIG. 5), out of
contact with heat pipes, of the first heat transfer plate members
2-1, 2-2, the first heat-dissipating fin section 5 composed of
thin-plate fins is arranged as thermally connected thereto. Between
the first heat transfer plate members 2-1, 2-2, the heat transfer
block 6 is arranged as thermally connected thereto. On one of
surfaces that is out of contact with the heat pipe of the second
heat transfer plate member 3 (upper side in FIG. 5), the second
heat-dissipating fin section 4 comprising thin-plate fins is
arranged almost entirely and thermally connected thereto.
[0056] FIGS. 6 to 10 are views for explaining a heat sink according
to another aspect of the present invention. FIG. 6 is a perspective
view, and FIG. 7 is a back side view. FIG. 7 is a top view. FIG. 9
is a front view and FIG. 10 is a lateral view. The details are the
same as those described with reference to FIGS. 1 to 5 except
covers 9-1, 9-2 that cover a part of the heat dissipating fins.
[0057] The first heat transfer plate members 2-1, 2-2 and the
second heat transfer plate member 3 are thermally connected to the
first heat dissipating fin section 5 and the second heat
dissipating fin section 4, and fixed by a fixing section 8
sandwiching the heat pipes 7-1 to 7-5 arranged side by side. The
plural heat pipes are arranged to be thermally connected at their
center parts to the heat transfer block 6 made of metal with
excellent heat transfer property. The heat transfer block 6 has end
block parts 6-1, 6-2 which are formed at both sides and made of
metal with excellent heat transfer property and the heat receiving
section 10, and the end block parts 6-1, 6-2 and the heat receiving
section 10 are formed integrally.
[0058] The heat transfer block 6 comprises the block parts 6-1, 6-2
and the heat receiving section 10. The block parts 6-1, 6-2 are
arranged in contact with the linear side surfaces at the centers of
the outermost two heat pipes 7-1, 7-5 and the heat receiving
section 10 is contact with the upper surface at the center of the
plural heat pipes 7-1 to 7-5. The heat generated by the heat
generating component is diffused in the lateral direction by such a
heat transfer block 6 above. Consequently, the heat is diffused
entirely to the heat sink and dissipated via the heat dissipating
fins to the outside of the heat sink.
[0059] FIGS. 11A, 11B and 11C are cross-sectional views for
explaining a shape of thin-plate fins of the heat sink of the
present invention that are bonded to a heat transfer plate member
(2-1, 2-2 or 3). The thin-plate fins may have various shapes in
accordance with conditions of place, placable space and the like of
the heat sink. Beside, variously-shaped thin-plate fins may be
combined freely.
[0060] In the aspect illustrated in FIG. 11A, plural thin plate
fins, each of which has a U-shaped cross section having a bottom
surface, a vertical surface and an upper surface, are arranged in
the lateral direction and in parallel to each other to be the heat
dissipating fin section 4. In this aspect, the plural bottom
surfaces are arranged in parallel to form a flat heat receiving
surface, to which the first heat transfer plate members 2-1, 2-2 or
the second heat transfer plate member 3 is connected. At the same
time, upper surfaces of the plural heat dissipating fins arranged
in parallel with each other form a flat surface. The thin plate
fins are connected, for example, by soldering, brazing or any other
well-known technique (this also goes for the other examples).
[0061] In the aspect illustrated in FIG. 11B, plural thin plate
fins, each of which has an L-shaped cross section having a bottom
surface and a vertical surface, are arranged in the lateral
direction and side by side each other to form the heat dissipating
fin section 4. Also in this aspect, the plural bottom surfaces are
arranged side by side to form a flat heat receiving surface and the
heat dissipating fin section 4 is open at the upper side.
[0062] In the aspect illustrated in FIG. 11C, the plural thin plate
fins, each of which has a U-shaped cross section having a bottom
surface, a vertical surface and an upper surface, and the plural
thin plate fins, each of which has an L-shaped cross section having
a bottom surface and a vertical surface, are combined appropriately
to form be the heat dissipating fin section 4. Combination is not
limited to the example shown in the figure, and any other
combination may be adopted. For example, combination may be such
that the heat dissipating fin sections 4, which are described with
reference to FIG. 11C, are arranged at both ends and the heat
dissipating fin section, which is described with reference to FIG.
11A, is arranged at the center.
[0063] The thin plate fins according to the aspects illustrated in
FIGS. 11A to 11C are fixed and bonded at bottom surfaces to the
first heat transfer plate 2 or second heat transfer plate 3 by
soldering, brazing or the like. Here, the thin plate fins according
to the aspects illustrated in FIGS. 11A to 11C may be combined
appropriately, including different-shape thin plate fins, on the
both surfaces of the second heat transfer plate member 3 and the
first heat transfer plate members 2-1 and 2-2. For example, the
thin plate fins are mounted on the lower surface of the first heat
transfer plate member 2-1 as illustrated in FIG. 11A and the thin
plate fins may be mounted on the upper surface of the second heat
transfer plate member 3 as illustrated in FIG. 11B.
[0064] As described above, according to the present invention, it
is possible to provide a high-performance heat sink that is
manufactured by a smaller number of mechanical works, light weight
and low-cost and capable of enhancing the heat-dissipating
performance.
REFERENCE NUMERALS
[0065] 1 heat sink [0066] 2-1, 2-2 first heat transfer plate member
[0067] 3 second heat transfer plate member [0068] 4 second heat
dissipating fin section [0069] 5 first heat dissipating fin section
[0070] 6 heat transfer block [0071] 6-1, 6-2 end block part [0072]
7-1 to 7-5 heat pipe [0073] 8 fixing part [0074] 9-1, 9-2 cover
[0075] 10 heat receiving section [0076] 20 heat generating
component
* * * * *