U.S. patent application number 14/423002 was filed with the patent office on 2015-08-06 for heat sink.
This patent application is currently assigned to FURUKAWA ELECTRIC CO., LTD.. The applicant listed for this patent is FURUKAWA ELECTRIC CO., LTD.. Invention is credited to Kenya Kawabata, Yasumi Sasaki.
Application Number | 20150219400 14/423002 |
Document ID | / |
Family ID | 50883461 |
Filed Date | 2015-08-06 |
United States Patent
Application |
20150219400 |
Kind Code |
A1 |
Sasaki; Yasumi ; et
al. |
August 6, 2015 |
HEAT SINK
Abstract
A heat sink that can reduce a load imposed on a heat pipe and
enhance a heat transfer efficiency from a heating body to a heat
radiation fin is provided. The heat sink has a base plate 21 having
a heat receiving portion to which a semiconductor device 11 is
thermally connected, a heat pipe disposed on the base plate 21
while partially brought into contact with the heat receiving
portion, and a heat radiation fin arranged to be stacked on the
base plate 21 and the heat pipe 22. The base plate 21 is formed of
a metal plate and has an opening portion 35 at the site
corresponding to the heat receiving portion, and the heat receiving
plate 36 which is formed of a metal plate having higher thermal
conductivity than the base plate 21 is arranged to form
substantially the same plane with the base plate 21.
Inventors: |
Sasaki; Yasumi; (Tokyo,
JP) ; Kawabata; Kenya; (Tokyo, JP) |
|
Applicant: |
Name |
City |
State |
Country |
Type |
FURUKAWA ELECTRIC CO., LTD. |
Tokyo |
|
JP |
|
|
Assignee: |
FURUKAWA ELECTRIC CO., LTD.
Tokyo
JP
|
Family ID: |
50883461 |
Appl. No.: |
14/423002 |
Filed: |
December 4, 2013 |
PCT Filed: |
December 4, 2013 |
PCT NO: |
PCT/JP2013/082635 |
371 Date: |
February 20, 2015 |
Current U.S.
Class: |
165/104.26 |
Current CPC
Class: |
H01L 2924/0002 20130101;
F28D 15/0233 20130101; H01L 21/4882 20130101; H01L 2924/00
20130101; F28D 15/04 20130101; F28D 15/0275 20130101; H01L 23/427
20130101; F28F 1/32 20130101; H01L 2924/0002 20130101 |
International
Class: |
F28D 15/02 20060101
F28D015/02; F28D 15/04 20060101 F28D015/04 |
Foreign Application Data
Date |
Code |
Application Number |
Dec 6, 2012 |
JP |
2012-267171 |
Claims
1. A heat sink comprising: a base plate having a heat receiving
portion to which a heating body is thermally connected; a heat pipe
disposed on the base plate while partially brought into contact
with the heat receiving portion; and a heat radiation fin disposed
to be stacked on the base plate and the heat pipe, wherein the base
plate is formed by folding a metal plate, and has a groove portion
on which the heat pipe is mounted, and a mount portion which is
located at both the sides of the groove portion and on which the
heat radiation fin is mounted, an opening portion is formed at a
site corresponding to the heat receiving portion of the groove
portion, and a surface of the groove portion and a back surface of
the mount portion are formed at the same height, and the heat
receiving portion formed of a metal plate having higher thermal
conductivity than the base plate is placed at the opening portion
so that one surface of the heat receiving plate and a surface of
the base plate on which the heat pipe is mounted form substantially
the same plane.
2. (canceled)
3. The heat sink according to claim 1, wherein the heat receiving
plate is fixed to the back surface of the mount portion.
4. The heat sink according to claim 1, wherein the heat radiation
fin has a plurality of fin plates equipped side by side, and the
fin plates are arranged along an extension direction of the heat
pipe.
5. The heat sink according to claim 1, wherein the heat radiation
fin has a plurality of reception grooves for receiving the heat
pipe on a surface thereof which confronts the base plate, and a leg
portion that comes into contact with the surface of the base plate
is equipped between the reception grooves.
6. The heat sink according to claim 3, wherein the heat radiation
fin has a plurality of fin plates equipped side by side, and the
fin plates are arranged along an extension direction of the heat
pipe.
7. The heat sink according to claim 3, wherein the heat radiation
fin has a plurality of reception grooves for receiving the heat
pipe on a surface thereof which confronts the base plate, and a leg
portion that comes into contact with the surface of the base plate
is equipped between the reception grooves.
8. The heat sink according to claim 4, wherein the heat radiation
fin has a plurality of reception grooves for receiving the heat
pipe on a surface thereof which confronts the base plate, and a leg
portion that comes into contact with the surface of the base plate
is equipped between the reception grooves.
Description
TECHNICAL FIELD
[0001] The present invention relates to a heat sink having a heat
pipe disposed in a base plate.
BACKGROUND ART
[0002] There is generally known a heat sink that has a base plate
having a heat receiving portion to which a heating body is
thermally connected, a heat pipe disposed in the base plate so as
to come into partial contact with the heat receiving portion, and a
heat radiation fin which is thermally connected to the heat pipe
(see Patent Document 1, for example).
PRIOR ART
Patent Document
[0003] Patent Document 1: Japanese Patent No. 4,999,060
SUMMARY OF THE INVENTION
Problem to be Solved by the Invention
[0004] In order to efficiently transfer heat from the heating body
to the heat radiation fin through the heat pipe in this type of
heat sink, the base plate which is brought into contact with the
heat pipe is desired to be formed of a material having excellent
thermal conductivity (for example, copper, copper alloy or the
like). However, when the whole body of the base plate is formed of
copper or copper alloy, the amount of copper to be used increases,
and causes a problem that the weight and the manufacturing cost
increase.
[0005] Furthermore, heat sinks are strongly required to be designed
in compact size. However, when the heat radiation fin is mounted
while stacked on the base plate, the heat pipe is sandwiched
between the base plate and the heat radiation fin, and thus it is
desired to reduce a load applied to the heat pipe.
[0006] The present invention has been implemented to solve the
above problem, and has an object to a heat sink that can reduce a
load applied to a heat pipe, and also enhance the heat transfer
efficiency from a heating body to a heat radiation fin.
Means of Solving the Problem
[0007] The specification of this application contains the whole
content of Japanese Patent Application No. 2012-267171 filed on
Dec. 6, 2012.
[0008] In order to attain the above object, according to the
present invention, a heat sink comprises a base plate having a heat
receiving portion to which a heating body is thermally connected, a
heat pipe disposed on the base plate while partially brought into
contact with the heat receiving portion, and a heat radiation fin
disposed to be stacked on the base plate and the heat pipe, wherein
the base plate is formed of a metal plate and has an opening
portion at a site corresponding to the heat receiving portion, and
the heat receiving portion formed of a metal plate having higher
thermal conductivity than the base plate is placed at the opening
portion so that one surface of the heat receiving plate and a
surface of the base plate on which the heat pipe is mounted form
substantially the same plane.
[0009] In the above construction, the base plate may be formed by
folding a metal plate to have a groove portion on which the heat
pipe is mounted, and a mount portion which is formed at both the
sides of the groove portion and on which the heat radiation fin is
mounted, the opening portion is equipped in the groove portion, and
the surface of the groove portion and the back surface of the mount
portion are formed at the same height. Furthermore, the heat
receiving plate may be fixed to the back surface of the mount
portion.
[0010] Furthermore, the heat radiation fin may have a plurality of
fin plates equipped side by side, and the fin plates may be
arranged along an extension direction of the heat pipe. the heat
radiation fin has a plurality of reception grooves for receiving
the heat pipe on a surface thereof which confronts the base plate,
and a leg portion that comes into contact with the surface of the
base plate may be equipped between the reception grooves.
Effect of the Invention
[0011] According to the present invention, the base plate is formed
of the metal plate and has the opening portion at the site
corresponding to the heat receiving portion. The heat receiving
portion which is formed of a metal plate having higher thermal
conductivity than the base plate is equipped at the opening
portion. Therefore, heat from a heating body can be efficiently
transferred to the heat radiation fin through the heat receiving
portion and the heat pipe. Furthermore, the heat receiving plate is
arranged within substantially the same plane (substantially
in-plane) as the surface of the base plate on which the heat pipe
is mounted, and thus occurrence of a step on the base plate can be
prevented. Even when the heat radiation fin is arranged to be
stacked on the base plate and the heat pipe, an excessively load
can be prevented from being imposed on the heat pipe.
BRIEF DESCRIPTION OF THE DRAWINGS
[0012] FIG. 1 is an exploded perspective view showing a heat sink
according to a first embodiment.
[0013] FIG. 2 is a perspective view showing the external appearance
of the heat sink.
[0014] FIG. 3 is a side view showing the heat sink.
[0015] FIG. 4 is a side cross-sectional view of the heat sink.
[0016] FIG. 5 is a plan view of a base plate before press
forming.
[0017] FIG. 6 is a side view showing a heat sink according to
another embodiment.
[0018] FIG. 7 is a side cross-sectional view of the heat sink.
MODES FOR CARRYING OUT THE INVENTION
[0019] A first embodiment according to the present invention will
be described hereunder with reference to the drawings.
First Embodiment
[0020] FIG. 1 is an exploded perspective view showing a heat sink
10 according to a first embodiment, and FIG. 2 is a perspective
view showing the external appearance of the heat sink 10.
[0021] The heat sink 10 is used for an electronic device such as a
personal computer or the like, for example, and it is thermally
connected to a semiconductor device (heating body) 11 such as CPU
or the like mounted on a circuit board (not shown) to cool the
semiconductor device 11.
[0022] As shown in FIG. 1, the heat sink 10 has a flat-plate type
base plate 21, plural (three in this embodiment) heat pipes 22 are
arranged side by side on the base plate 21, and plural (two in this
embodiment) heat radiation fins 23 are arranged side by side while
stacked on the base plate 21 and the heat pipes 22. That is, in
this construction, the heat pipes 22 are sandwiched and held
between the base plate 21 and the heat radiation fins 23 as shown
in FIG. 2.
[0023] The base plate 21 is formed by folding a metal plate of
aluminum or the like through press forming. As shown in FIG. 1, the
base plate 21 has a wide groove portion 31 extending in the
longitudinal direction (in the direction of Y in FIG. 1)
substantially at the center in the short-length direction (in the
direction of X in FIG. 6), and a pair of bank portions (mount
portions) which are disposed at both the sides of the groove
portion 31 and formed to be higher than the groove portion 31.
These bank portions 32 are formed at substantially the same height
position, and each of the edge portions 33 thereof is folded
downwards. The heat pipes 22 are mounted on the groove portion 31,
and the heat radiation fins 23 are mounted on the bank portions
32.
[0024] Hole portions 34 are formed at two positions of each bank
portion 32 (totally, four positions). These hole portions 34 are
holes through which fixing screws for fixing the heat sink 10 to a
circuit board penetrate.
[0025] The groove portion 31 is placed substantially at the center
in the width direction of the base plate 21, but the present
invention is not limited to this style. The groove portion 31 may
be placed at any position in the width direction.
[0026] This type of base plate may be formed not only by folding a
metal plate, but also by a die-casting method, an extrusion molding
method or a cutting method. However, the die-casting method and the
extrusion molding method need a cost for dies or molds, and thus
these methods are not suitable for small production. Even the
cutting method has a problem that a processing cost and a material
cost are increased. Furthermore, since a die-cast product is
generally inferior to a metal plate in thermal conductivity, the
cooling performance is fluctuated in accordance with the difference
in thermal conductivity of the base plate when the other conditions
are identical.
[0027] On the other hand, according to this construction, the base
plate 21 is formed by folding a metal plate through press forming.
This construction can enhance the thermal conductivity of the base
plate 21 itself, and also reduce the manufacturing cost as compared
with the foregoing methods. Furthermore, the groove portion 31 and
the edge portions 33 which are folded in the base plate 2 function
as reinforcing ribs, so that the base plate 21 can be configured to
be light and thin while securing stiffness.
[0028] In this construction, the base plate 21 has an opening
portion 35 substantially at the center in the longitudinal
direction of the groove portion 31 (the position corresponding to a
heat receiving portion to be thermally connected to the
semiconductor device 11), and a heat receiving plate 36 which is
formed of metal having higher thermal conductivity (for example,
copper) than the base plate 21 is mounted at the opening portion
35. The semiconductor device 11 is connected to the back surface
(lower surface in FIG. 1) 36A of the heat receiving plate 36, and
the heat receiving plate 36 is fixed while the heat pipes 22 are
partially brought into contact with the surface (upper surface in
FIG. 1) 36B of the heat receiving plate 36.
[0029] In the construction, heat generated from the semiconductor
device 11 is transferred to the heat pipes 22 through the heat
receiving plate 36. Since the heat receiving plate 36 is formed of
the metal having higher thermal conductivity than the base plate
21, the heat of the semiconductor device 11 can be rapidly
transferred to the heat radiation fins 23 through the heat
receiving plate 36 and the heat pipes 22, and the cooling
performance of the heat sink 10 can be enhanced. Furthermore, the
weight can be reduced, and the costs for materials and
manufacturing can be more greatly reduced as compared with a case
where the whole body of the base plate 21 is formed of copper.
[0030] The heat pipes 22 are members for diffusing the heat
received by the heat receiving plate 36 to the heat radiation fins
23. For example, the heat pipe 22 is formed by encapsulating
operating fluid such as water or the like under pressure-reduced
state in a hermetically sealed container which is formed of metal
having excellent thermal conductivity such as copper or the like or
formed of alloy of the metal. The container is configured in a flat
shape to reduce the height (thickness) thereof and secure a large
contact area with the base plate 21 and the heat radiation fins 23.
The heat pipes 22 are fixed to the groove portion 31 of the base
plate 21 and the heat receiving plate 36 by soldering, brazing or
the like.
[0031] The heat radiation fin 23 serves to discharge the heat
transferred through the heat pipes 22 into air, and is configured
to have the substantially half length of the heat pipes 22. Two
heat radiation fins 23 are arranged side by side in the extension
direction of the heat pipes 22. The heat radiation fins 23 are
formed in a region containing an area just above the heat receiving
plate 36, and exist over a broad area on the base plate 21. The
number of the heat radiation fins 23 to be arranged may be
arbitrarily changed in accordance with the length of the heat pipes
22, and it is needless to say that they may be configured as a
single heat radiation.
[0032] Each heat radiation fin 23 has plural fin plates 43 each of
which is formed to have a substantially U-shaped cross-section by
folding an upper edge 41 and a lower edge 42 of a metal plate 40 of
aluminum or the like substantially in parallel to each other, for
example.
[0033] These fin plates 43 are arranged side by side in the
extension direction of the heat pipes 22, and the respective fin
plates 43 are fixed integrally with one another by soldering, for
example. Air is allowed to flow through the gap between the
adjacent fin plates 43. Therefore, the heat transferred to the heat
pipes 22 can be diffused to the whole bodies of the heat radiation
fins 23, and this heat can be heat-exchanged with air flowing
through the gap between the fin plates 43, whereby the heat can be
radiated.
[0034] Reception grooves 24 in which the heat pipes 22 are received
are formed on the lower surface (confronting surface) 23A of the
heat radiation fin 23 which confronts the base plate 21 and the
heat pipes 22. The reception groove 24 is formed in conformity with
the outer shape of the heat pipe 22, and enhances the thermal
transfer area between the heat pipe 22 and the heat radiation fin
23.
[0035] A leg portion 25 is equipped between the respective
reception grooves 24, and these leg portions 25 come into contact
with the surface of the groove portion 31 of the base plate 21 (the
surface on which the heat pipes 22 are mounted) 31A when the heat
radiation fins 23 are mounted on the bank portions 32 of the base
plate 21, whereby thermal conduction can be directly performed from
the base plate 21 to the heat radiation fins 23 through the leg
portions 25, and the load of the heat radiation fins 23 is
supported by the leg portions 25, thereby reducing the load applied
to the heat pipes 22.
[0036] In this embodiment, the heat radiation fins 23 are fixed to
the base plate 21 and each heat pipe 22 by soldering or the like,
whereby the heat sink 10 is integrally configured. Furthermore, the
heat radiation fins 23 are equipped with cut-out portions at the
positions corresponding to the hole portions 34 formed in the base
plate 21.
[0037] In the heat sink 10 described above, in order to enhance the
thermal conductivity of the base plate 12 with an inexpensive
construction, the base plate 21 is formed by folding a metal plate,
the opening portion 35 is formed at the position corresponding to
the heat receiving portion which is thermally connected to the
semiconductor device 11, and the heat receiving plate 36 formed of
metal having higher thermal conductivity than the base plate 21 is
disposed at the opening portion 35.
[0038] The heat sink 10 is configured by stacking the heat
radiation fins 23 on the base plate 21, and thus the heat pipes 22
are sandwiched between the base plate 21 and the heat radiation
fins 23. Therefore, it is desired to reduce the load of the heat
radiation fins 23 imposed on the heat pipes 22.
[0039] Therefore, in this construction, the heat receiving plate 36
is disposed so that no step or a remarkably slight step exists
between the surface (upper surface; one surface in the FIG. 36B of
the heat receiving plate 36 and the surface (upper surface in the
FIG. 31A of the groove portion 31 of the base plate 21, that is,
the surface 36B of the heat receiving plate 36 and the surface 31A
of the groove portion 31 of the base plate 21 are arranged to form
substantially the same plane (are arranged substantially within the
same plane).
[0040] Specifically, as shown in FIG. 3, the base plate 21 is
formed by folding the metal plate so that the surface 31A of the
groove portion 31 and the back surfaces (lower surfaces in FIG. 3)
of the bank portions 32 are located at the same height position,
and the heat receiving plate 36 is configured to be larger in width
than the groove portion 31 and fixed to the back surfaces 32A of
the bank portions 32 by soldering or the like.
[0041] Accordingly, the surface 36B of the heat receiving plate 36
and the surface 31A of the groove portion 31 can form substantially
the same plane (be arranged within substantially the same plane)
and the heat receiving plate 36 can be arranged at the opening
portion 35 of the base plate 21 by a simple work of applying the
heat receiving plate 36 to the opening portion 35 from the side of
the back surfaces 32A of the bank portions 32 and fixing the heat
receiving plate 36 to the back surfaces 32A as shown in FIG. 4.
Therefore, the step between the heat receiving plate 36 and the
base plate 21 can be prevented, and even when the heat radiation
fins 23 are stacked and arranged on the base plate 21 and the heat
pipes 22, an excessively load can be prevented from being imposed
on the heat pipes 22.
[0042] Next, a method of forming the base plate 21 will be
described.
[0043] FIG. 5 is a plan view before press forming of the base plate
21.
[0044] First, a metal plate is punched out to have an outer shape
shown in FIG. 5, and an opening portion 35 and hole portions 34 are
formed at predetermined positions.
[0045] Subsequently, the punched metal plate is folded to have a
desired shape by press forming. Specifically, the punched metal
plate is mountain-folded along lines 50 extending thereon while the
lines 50 are spaced inwards from the edges of the metal plate by a
predetermined distance, and lines 51 extending along the edge
portions 35A of the opening portion 35, and also valley-folded
along lines 52 extending thereon while the lines 52 are spaced
inwards from the lines 51 by a predetermined distance, thereby
forming the base plate 21.
[0046] In this case, recess portions 35B extending outwards from
the edge portions 35A are formed at the four corners of the edge
portions 35A of the opening portion 35. Accordingly, when the metal
plate is folded along the lines 51, spreading at the four corners
of the opening portion 35 can be prevented, and the metal plate can
be accurately folded along the edge portions 35A of the opening
portion 35.
[0047] As described above, the heat sink according to this
embodiment comprises the base plate 21 having the heat receiving
portion to which the semiconductor device 11 is thermally
connected, heat pipes 22 disposed on the base plate 21 while
partially coming into contact with the heat receiving portion, and
the heat radiation fins 23 disposed to be stacked on the base plate
21 and the heat pipes 22, the base plate 21 is formed of a metal
plate and has the opening portion 35 at the site corresponding to
the heat receiving portion, and the heat receiving plate 36 formed
of a metal plate having higher thermal conductivity than the base
plate 21 is equipped at the opening portion 35. Therefore, heat
from the semiconductor device 11 can be efficiently transferred to
the heat radiation fins 23 through the heat receiving plate 36 and
the heat pipes 22. Furthermore, the heat receiving plate 36 forms
substantially the same plane with (is arranged within substantially
the same plane as) the surface 31A of the base plate 21 on which
the heat pipes 22 are mounted. Therefore, occurrence of a step on
the base plate 21 is prevented, and even when the heat radiation
fins 23 are arranged to be stacked on the base plate 21 and the
heat pipes 22, an excessive load can be prevented from being
applied to the heat pipes 22.
[0048] According to this embodiment, the base plate 21 is formed by
folding the metal plate, and has the groove portion 31 on which the
heat pipes 22 are mounted, and the bank portions 32 which are
mounted at both the sides of the groove portion 31 and on which the
heat radiation fins 23 are mounted. The opening portion 35 is
formed in the groove portion 31, and the surface 31A of the groove
portion 31 and the back surfaces 32A of the bank portions 32 are
formed at the same height. Therefore, the heat receiving plate 36
can be disposed at the opening portion 35 of the base plate 21 so
that the surface 36B of the heat receiving plate 36 and the surface
31A of the groove portion 31 form substantially the same plane (are
arranged within substantially the same plate) by s simple work of
applying the heat receiving plate 36 from the side of the back
surfaces 32A of the bank portions 32 to the opening portion 35 and
fixing the heat receiving plate 36 to the back surfaces 32A.
[0049] According to this embodiment, since the heat receiving plate
36 is fixed to the back surfaces 32A of the bank portions 32, the
fixing structure can be simplified, and the fixed portion is not
exposed to the outside, so that the external appearance of the heat
sink 10 can be enhanced.
[0050] Furthermore, according to this embodiment, the heat
radiation fin 23 has plural fin plates 43 arranged side by side,
and these fin plates 43 are arranged along the extension direction
of the heat pipes 22. Therefore, heat transferred through the heat
pipes 22 can be diffused to each of the fin plates 43, and the heat
can be heat-exchanged with air flowing through the gap between the
fin plates 43 to be radiated.
[0051] Still furthermore, according to this embodiment, the heat
radiation fin 23 has the plural reception grooves 24 for
accommodating the heat pipes 22 on the lower surface 23A thereof
which confronts the base plate 21, and the leg portions 25 which
come into contact with the surface 31A of the groove portion 31 of
the base plate 21 are equipped between the reception grooves 24A.
Therefore, when the heat radiation fins 23 are mounted on the bank
portions 32 of the base plate 21, the leg portions 25 come into
contact with the surface 31A of the groove portion 31 of the base
plate 21, whereby thermal conduction can be directly performed from
the base plate 21 through the leg portions 25 to the heat radiation
fins 23. Furthermore, the load of the heat radiation fins 23 can be
supported by the leg portions 25, and thus the load imposed on the
heat pipes 22 can be reduced.
Second Embodiment
[0052] Another embodiment of the heat sink will be described. The
heat sink 100 of the second embodiment is different from the first
embodiment in the shape of the base plate. In the second
embodiment, only the structural difference will be described. The
same constituent elements are represented by the same reference
numerals, and the descriptions thereof are omitted.
[0053] FIG. 6 is a side view showing the heat sink 100 according to
the second embodiment, and FIG. 7 is a side cross-sectional view
showing the heat sink 100.
[0054] The base plate 121 of this embodiment is formed by a metal
plate which has not been subjected to the folding (bending) work.
In this embodiment, the heat receiving plate 36 is formed to have
substantially the same size as the opening portion 135 formed in
the base plate 121 and the heat receiving plate 36 is fixed to the
opening portion 135 so that the surface 36B of the heat receiving
plate 36 and the surface (upper surface in FIG. 6) 121A of the base
plate 121 form substantially the same plane (are arranged within
substantially the same plane).
[0055] Specifically, a backing pad is disposed at the surface 121A
side of the base plate 121 (the surface on which the heat pipes 22
are mounted), and the base plate 121 and the heat receiving plate
36 are fixed to each other from the back surface 121B side of the
base plate 121 by soldering or the like while the surface 36B of
the heat receiving plate 36 is brought into contact with the
backing plate. In this construction, a higher skill is needed to
fix the heat receiving plate as compared with the first embodiment.
However, the surface 36B of the heat receiving plate 36 and the
surface 121A of the base plate 121 can form substantially the same
plane (be arranged within substantially the same plane).
[0056] According to this embodiment, the thickness of the base
plate 121 can be reduced, and thus the heat sink 100 can be
configured to be thin.
[0057] The present invention has been specifically described on the
basis of the embodiments. However, the present invention is not
limited to the above embodiments, and the embodiments may be
modified without departing from the subject matter of the present
invention.
[0058] For example, in the above embodiments, the three heat pipes
22 are mounted on the base plate 21, 121, but the number of heat
pipes 22 may be arbitrarily changed. The heat pipe 22 is configured
to be flat, but it may be configured in a round shape.
[0059] In the above embodiments, the opening portion 35, 135 is
equipped substantially at the center of the base plate 21, 131.
However, the present invention is not limited to this style, and
the locating position thereof may be changed in accordance with the
position of the semiconductor device 11 mounted in the circuit
board. Furthermore, in the above embodiments, the semiconductor
device 11 mounted on the circuit board is set as a heating body.
However, the present invention is not limited to this style.
DESCRIPTION OF REFERENCE NUMERALS
[0060] 10, 100 heat sink [0061] 11 semiconductor device (heating
body) [0062] 21, 121 base plate [0063] 22 heat pipe [0064] 23 heat
radiation fin [0065] 23A lower surface (confronting surface) [0066]
24 reception groove [0067] 25 leg portion [0068] 31 groove portion
[0069] 31A, 121A surface (surface on which heat pipes are arranged)
[0070] 32 bank portion [0071] 32A back surface [0072] 35, 135
opening portion [0073] 36 heat receiving plate [0074] 36B surface
[0075] 43 fin plate
* * * * *