US20120247735A1

US20120247735A1 - Heat sink

Info

Publication number: US20120247735A1
Application number: US13/455,717
Authority: US
Inventors: Shinichi Ito; Kenya Kawabata; Shinichi Furumoto
Original assignee: Furukawa Electric Co Ltd
Current assignee: Furukawa Electric Co Ltd
Priority date: 2010-02-26
Filing date: 2012-04-25
Publication date: 2012-10-04
Also published as: CN102484105A; WO2011105364A1; JPWO2011105364A1; TWI458927B; TW201144737A; JP5684228B2

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.

Description

TECHNICAL FIELD

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

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.
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.
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.
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.
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.
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.
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

PL1: Japanese Patent Application Laid-Open No. 2009-198173
PL2: Japanese Patent Application Laid-Open No. H10 (1998)-107192

SUMMARY OF INVENTION

Technical Problem

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.
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.
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

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.
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.
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.
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.
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.
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.
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.
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.
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

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

FIG. 1 is a perspective view for explaining an aspect of a heat sink of the present invention;

FIG. 2 is a view illustrating a back surface of the heat sink according to the aspect of the present invention;

FIG. 3 is a top view of the heat sink according to the aspect of the present invention;

FIG. 4 is a front view of the heat sink according to the aspect of the present invention;

FIG. 5 is a lateral view of the heat sink according to the aspect of the present invention;

FIG. 6 is a perspective view for explaining a heat sink according to another aspect of the present invention;

FIG. 7 is a view illustrating a back surface of the heat sink according to the other aspect of the present invention;

FIG. 8 is a top view of the heat sink according to the other aspect of the present invention;

FIG. 9 is a front view of the heat sink according to the other aspect of the present invention;

FIG. 10 is a lateral view of the heat sink according to the other aspect of the present invention; and

FIGS. 11A, 11B and 11C are cross-sectional views for explaining shapes of thin-plate fins of the present invention.

DESCRIPTION OF EMBODIMENTS

With reference to the drawings, description is made about a heat sink according to the present invention.
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.
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.
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.
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.
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.
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.
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.
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.
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.
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.
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.
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.
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.
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.
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.
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.
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.
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.
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.
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.
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.
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.
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.
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.
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).
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.
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.
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.
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

1 heat sink
2-1, 2-2 first heat transfer plate member
3 second heat transfer plate member
4 second heat dissipating fin section
5 first heat dissipating fin section
6 heat transfer block
6-1, 6-2 end block part
7-1 to 7-5 heat pipe
8 fixing part
9-1, 9-2 cover
10 heat receiving section
20 heat generating component

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.