JPH0864731A - Heat conducting member and cooler and electronic apparatus employing the same - Google Patents

Abstract

PURPOSE: To provide a heat conducting member which has a flexible structure which can follow the variation of a distance between a heat generating member and a heat radiation member and produces a proper pressing force and can transmit the heat with a low thermal resistance and an electronic apparatus employing the heat conducting member. CONSTITUTION: A flat spring 5 which is spread in a surface direction so as to produce a force against the contact plane is enclosed in a bag of a flexible film 6 with grease 4 having a high thermal conductivity to provide a heat conducting member 1. The heat conducting member 1 is provided between a heat generating member 21 mounted on a wiring board 2 and a heat radiation member 3. The flat spring 5 is made of copper system alloy. The fluid grease 4 is enclosed in the bag of the flexible film 6.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a heat-conducting member and a cooling device and an electronic device using the same, and more particularly to a heat-dissipating member interposed between a heat-generating member and a heat-dissipating member. The present invention relates to a heat conducting member that transfers heat to a member to keep the heat generating member at a predetermined temperature, a cooling device using the same, and an electronic device.

[0002]

2. Description of the Related Art As a conventional heat conducting member, Japanese Patent Application Laid-Open No. 61-61
As described in JP-A-244050, JP-A-56-125896, and JP-A-4-48797, an example in which a metal plate is shaped like a leaf spring and is interposed between a heat generating member and a heat radiating member to cool it It is shown. In addition, JP-A-55-1
As described in JP-A-25699 and JP-A-63-28098, an example in which an elastic resin is interposed between a heat-generating member and a heat-dissipating member and cooled is shown. Further, Japanese Patent Application Laid-Open No. 2-166755 discloses an example in which a grid-like groove is provided in a gel-like resin and the resin is brought into contact with a small force.

[0003]

In the above-mentioned conventional leaf spring structure, it is necessary to reduce the thickness of the metal plate in order to bring them into contact with each other with a small force. Along with this, the cross-sectional area of the leaf spring is reduced, the thermal resistance between the heat generating member and the heat radiating member is increased, and sufficient cooling performance cannot be obtained. On the other hand, in the example of using the elastic resin, when the distance between the heat generating member and the heat radiating member changes due to external impact or thermal deformation, even if the resin itself has elasticity,
The structure is such that the entire contact surface is not deformed in the thickness direction unless a large force is applied, which causes a problem of damaging the heat generating member. Furthermore, the distance between the heat-generating member and the heat-dissipating member is such that the displacement cannot be followed when the distance becomes large, and there is a problem that heat cannot be transferred if a gap is created on the contact surface. JP-A-2-166
In the example described in Japanese Patent No. 755 publication, a groove is formed on the surface in order to solve this problem, but it is necessary to increase the groove width in order to relax the force, and as a result, a disconnection that contributes to heat conduction. There is a problem that the area becomes small and sufficient cooling performance cannot be obtained. Further, in the example using the resin having elasticity, when there is a temperature distribution in the contact surface of the heat generating member,
Since the thermal conductivity is relatively small, heat was not diffused in the surface direction, and the cross section of the thermal conductive member was not effectively utilized.

A first object of the present invention is to use a heat conducting member having a flexible structure which follows the fluctuation of the distance between the heat generating member and the heat radiating member and generates an appropriate pressing force, and the heat conducting member. To provide a cooling device and an electronic device.

A second object of the present invention is to provide a heat conducting member which has a flexible structure and which conducts heat with a small thermal resistance by diffusing the heat in the contact surface direction of the heating member, a cooling device using the same, and an electronic device. To provide equipment.

A third object of the present invention is to provide a heat conducting member capable of simultaneously achieving the first and second objects, a cooling device using the same, and an electronic apparatus.

[0007]

In order to achieve the first object, the heat conducting member of the present invention is interposed between a heat generating member and a heat radiating member to radiate heat generated by the heat generating member. A heat-conducting member for transferring heat to a flexible film formed in a bag shape, a liquid medium having fluidity enclosed in the bag-shaped film, and the film. And a spring member that generates a pressing force.

Further, the heat conducting member is one in which a liquid medium having fluidity and a spring member are housed in a concave portion formed in the heat radiating member, and the heat conducting member is sealed in the film by a flexible film. The spring member is configured to generate a pressing force against the film.

Further, the spring member is a leaf spring and is provided with a plurality of tongue pieces. Further, the flexible film is formed into a film shape by a resin layer having a relatively high melting point on the outer side, an aluminum foil layer on the middle side, and a resin layer having a lower melting point than the resin of the outermost layer on the inner side. The films are adhered to each other by heat fusion.

In order to achieve the second object, the heat conducting member of the present invention is interposed between a heat generating member and a heat radiating member and transfers heat generated by the heat generating member to the heat radiating member. A member, wherein the heat-conducting member generates a flexible film formed in a bag shape, a liquid medium having a high heat conductivity enclosed in the bag-shaped film, and a pressing force to the film. And a spring member having a high thermal conductivity and having a surface extending in a direction parallel to the contact surface with the heat generating member.

Further, a plurality of the heat generating members are mounted, and a plurality of tongue pieces of the spring member are formed at positions corresponding to the plurality of heat generating members. The thickness of the heat conducting member is 5 mm or less. Further, the liquid medium is Zn in silicon oil.
It is a mixture of O, diamond, or metal particles. In addition, two fins are provided, the two fins are arranged in combination, and the combination of the surfaces is filled with the gel resin.

In order to achieve the third object, the heat conducting member of the present invention is interposed between a heat generating member and a heat radiating member and transfers heat generated in the heat generating member to the heat radiating member. A member, wherein the heat conducting member has a flexible film formed in a bag shape, and spreads in a direction parallel to a contact surface between the liquid medium having high heat conductivity and the heat generating member. It is characterized in that a fin having a surface base and a spring member having a high thermal conductivity for generating a pressing force against the film are enclosed in the bag-shaped film.

Further, the heat conducting member is interposed between the plurality of heat generating members and the heat radiating member and transfers the heat generated in the plurality of heat generating members to the heat radiating member, wherein the heat conducting member is the plurality of heat conducting members. A flexible film formed in a bag shape that contacts the heat generating member, a liquid medium having high heat conductivity enclosed in the bag film, and the film corresponding to each of the plurality of heat generating members. And a spring member having a high thermal conductivity and having a surface that spreads in a direction parallel to a contact surface with the heat generating member that generates the pressing force.

Further, the heat-conducting member has a part of a fin having a base whose surface extends in a direction parallel to a contact surface with the heat-generating member, and is inserted into the gel-like resin so that the bottom of the fin has a space. It is characterized in that it is molded.

Further, the heat conducting member is provided with a metal plate having a surface extending in a direction parallel to the contact surface with the heat generating member in the gel-like resin, and part of the uneven portion formed on the heat radiating member is provided. It is characterized in that it is formed by being inserted into a gel-like resin so that the bottom of the uneven portion has a space.

In order to achieve the above-mentioned objects 1 to 3, the cooling device of the present invention has the heat conducting member according to any one of claims 2, 3, 5 and 6 in the direction parallel to the heat generating member side. The present invention is characterized in that a spring member or base having an expanding surface is arranged and is interposed between the heat generating member and the heat radiating member.

In order to achieve the above objects 1 to 3, an electronic device according to the present invention is an electronic device in which an electronic circuit board having a plurality of semiconductor elements mounted thereon and its peripheral devices are housed in a housing having a metal surface. In the above, the heat conducting member according to any one of claims 1 to 13 is interposed between the semiconductor element and the metal surface of the housing.

Further, in an electronic device in which an electronic circuit board on which a plurality of semiconductor elements are mounted and its peripheral devices are housed in a metal casing, a specific semiconductor element is mounted on the electronic circuit board on which the semiconductor elements are mounted. The heat conducting member according to any one of claims 1 to 13 is interposed between the specific semiconductor element and the metal wall surface of the housing. It is characterized by that.

[0019]

The heat conducting member of the present invention and the electronic equipment using the same have the following actions because they are configured as described above.

The heat conducting member has flexibility because the fluid grease is enclosed in a flexible film bag. Also, because the leaf spring is enclosed, even if the distance between the heat generating member and the heat radiating member changes due to external impact or thermal deformation due to the pressing force of the leaf spring, it will follow it and generate heat with an appropriate force. It is pressed against the member and the heat dissipation member.
Further, since the leaf spring has a metal surface that spreads in the contact surface direction with the heat generating member, heat is diffused in the contact surface direction by the metal having high thermal conductivity. For this reason, the entire cross section of the heat conducting member contributes to heat conduction, the heat is transmitted from the heat generating member to the heat radiating member with a small thermal resistance due to the high thermal conductivity of the heat conductive grease, and the heat generating member is efficiently cooled.

Further, since a part of the fin is made to penetrate into the resin having high heat conductivity and is molded, the distance between the heat generating member and the heat radiating member is applied from the outside due to impact or thermal deformation. The gel-like resin is deformed in the shearing direction even if it is changed by the above-mentioned method, so that it is easily deformed and has a spring property. On the other hand, the conduction distance is shortened because the fin portion is embedded in the resin. Furthermore, since the area of the fin portion is expanded, the area that contributes to heat conduction is large, and the fin has a much higher thermal conductivity than gel-like resin, so heat is transmitted from the heat generating member to the heat radiating member with a small thermal resistance. The heat generating member is efficiently cooled.

Further, since the heat conducting member is interposed between the wiring board on which a plurality of heat generating members are mounted and the metal casing wall, even if the heights of the heat generating members vary, heat is generated by each heat generating member. The member and the metal housing wall are efficiently and thermally connected to each other, and due to the high thermal conductivity of the metal housing, the heat is widely diffused to the housing wall and high heat dissipation performance is obtained. Therefore, the heating element can be cooled efficiently.

[0023]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS A first embodiment of the present invention will be described with reference to FIGS. FIG. 1 is a cross-sectional view of the electronic device of this embodiment, and FIG.
5 to FIG. 5 are vertical sectional views of the heat conducting member.

The present embodiment shows an example in which a heat conducting member is applied to cooling an electronic device, and as can be seen from FIG. 1 showing the overall configuration of the electronic device, the electronic device of the present embodiment has a wiring. The semiconductor element 21 of the substrate 2 having a particularly large heat generation amount
The surfaces on which a and 21b are mounted are installed so as to face the metal housing 39, and the heat conduction member 1 is interposed between the surfaces of the semiconductor elements 21a and 21b and the metal housing. A claw 38 is provided on the wall of the housing 39, and the claw 38 prevents the heat conducting member 1 from falling off.

The heat conducting member 1 is constructed as follows. As shown in FIG. 2, the heat conductive member 1 includes a flexible film 6 formed in a bag shape, a grease 4 having fluidity and high heat conductivity, and a contact surface with respect to the contact surface. It is formed by enclosing a leaf spring 5 having a spread in the surface direction so as to generate a force in the pushing direction. The heat conducting member 1 is interposed between the heat generating electronic component 21 mounted on the wiring board 2 and the heat radiating member 3. The heat dissipating member 3 is composed of a metal wall forming a housing, a heat dissipating fin, or the like. The thermally conductive grease 4 is obtained by mixing particles of ZnO, diamond, or metal in silicone oil.
The flexible film 6 has a multi-layer structure. The outer side is a resin layer having a relatively high melting point, the middle is an aluminum foil layer, and the inner side is a resin layer having a lower melting point than the resin of the outermost layer, and is formed into a film shape. The films are adhered to each other by heat fusion of the resin layer. The aluminum foil has a barrier property against the oil component of grease. The leaf spring 5 is formed of a copper alloy plate such as phosphor bronze or brass, and is formed by bending both ends of the plate into a U shape. The reason why the material is a copper-based metal is that the spring itself also has high heat conduction by such a configuration. The plate thickness of the plate spring 5 is selected according to the pressing force of the plate spring 5, but a plate spring having a thickness of about 0.5 mm or less is used. In addition, the end portion is folded back to form the folded portion 51.
The folded portion 51 is provided with a function of a stopper so that the leaf spring 5 does not deviate from the elastic deformation range due to extreme deformation.

The heat-conducting member 1 of this embodiment has a flexible film 6
Since the grease having fluidity is enclosed in the bag, it has flexibility. Further, since the leaf spring 5 is enclosed, the heat generating electronic component 21 is pressed by the pressing force of the leaf spring 5.
Even if the distance between the heat radiating member 3 and the heat radiating member 3 changes due to an external impact or thermal deformation, the change in the distance is followed and the heat generating electronic component 21 and the heat radiating member 3 are pressed with appropriate force. Further, since the leaf spring 5 is formed to have a metal surface that spreads in the contact surface direction, heat is diffused in the contact surface direction through the metal surface having high thermal conductivity. Therefore, the entire cross section in the contact surface direction of the metal surface contributes to heat transfer, and the heat conduction of the heat conduction member 3 and the heat conduction grease having high heat conductivity from the heat generating electronic component 21 to the heat radiation member 3 with a small heat resistance. Since heat is transmitted, the heat-generating electronic components are efficiently cooled.

FIG. 3 shows a modification of the heat conducting member. This example has the same configuration as that of FIG. 2, but the tongue portion 5a of the leaf spring 5 is
To increase the heat transfer by the heat conduction of the spring itself and further reduce the thermal resistance. Leaf spring 5
May form a plurality of tongue pieces 5a from one plate,
In this case, the tongue piece 5a is formed by folding it back from the center of the plate. In addition, in the leaf spring as described in FIG.
It may be formed by joining the tongue pieces 5a later. Leaf spring 5
When the number of the tongue pieces 5a is increased, the pressing force increases. Therefore, in order to properly adjust the pressing force, it is necessary to reduce the plate thickness. Since the spring constant of the leaf spring 5 is proportional to the cube of the plate thickness, for example, when the number of tongues 5a is doubled, the spring force doubles at the same plate thickness. To set the same spring force as the example, the leaf spring 5a
The plate thickness of 0.79 times. In this case, since the plate thickness is only 0.79, the heat conduction of the plate spring 5 itself does not decrease so much, and the effect of reducing the thermal resistance as described above is not so impaired. In addition, when the heat generation amount of the heat generating electronic component is relatively small, the heat conduction member may be configured by only the leaf spring 5.

In the example shown in FIG. 1, the bottom surface of the housing is used as a heat radiation surface. However, for example, the metal plate 63 supporting the keyboard 36 is used as a heat radiation surface. The wiring board 2 and the heat conducting member 1 may be installed so as to be used.

FIG. 4 shows a modification of the heat conducting member.
In this example, in the same manner as the embodiment shown in FIG. 2, in the flexible film 6 formed in a bag shape, together with the grease 4 having fluidity and high thermal conductivity, the same area as that of the heat-generating electronic component or its The metal fins 7 having the bases having the above contact areas are combined so that the fins face each other. In this embodiment, the coil spring 8 is provided at the center of the fins 7.
The leaf springs 52 are brought into contact with the base portions at both ends of the to seal. Here, aluminum, copper, or the like is used as the metallic fin 7. Both the coil spring 8 and the leaf spring 52 may be provided, or either one may be provided.

According to the present embodiment, the heat conducting member 1 has flexibility as described in the embodiment shown in FIGS. 2 and 3, and is appropriately pressed between the heat generating electronic component and the heat radiating member. Power is gained. Further, since the fin 7 has a base portion that spreads in the contact surface direction, heat is diffused in the contact surface direction by the metal having a high thermal conductivity, so that the heat conducting member contributes to the heat conduction and at the fin portion. The area has been expanded,
Highly efficient heat transfer can be obtained. The smaller the gap between the fins is, the shorter the heat conduction distance becomes, so the heat conduction performance is improved, but the flexibility is lowered. Therefore, the fin thickness appropriate for the mounting condition of the heat-generating electronic component in the equipment is required. , Number of sheets,
The inter-fin gap is selected.

FIG. 5 shows a modification of the heat conducting member.
In this example, one heat conducting member 1 is interposed between a plurality of heat generating electronic components 21 and 22 mounted on the wiring board 2 and having different heights, and a plurality of heat conducting members 1 having different heights. This is an example of a case where the heat-generating electronic components are collectively cooled. The structure of the heat conduction member 1 is the same as that of the embodiment shown in FIG. 1, but one leaf spring 5 provided on the heat dissipation member 3 side is provided with a plurality of tongue pieces at positions corresponding to the heat generating electronic components 21 and 22. 5a, 5b,
5c is provided to generate a pressing force on each of the heat generating electronic components 21 and 22. The tongues 5a, 5b, 5c have a structure in which each part of the leaf spring 5 which is a single metal plate is folded back in a U shape, or a plurality of tongues 5a, 5b are provided on the leaf spring 5 which is a single metal plate. It may have a structure in which 5c are joined.

According to the present embodiment, even when a plurality of heat-generating electronic components having different heights are mounted on the wiring board 2, it is possible to efficiently cool them collectively.

A second embodiment of the present invention will be described with reference to FIGS. 6 and 7 are vertical cross-sectional views of the heat conducting member of this embodiment.

As can be seen from FIG. 6, the heat conducting member of this embodiment has the same structure as that of the embodiment shown in FIG. 5, but the wiring board 2, the plurality of semiconductor chips 23 and 24, the heat conducting member 1, It is an example of a multi-chip module configured by a radiation fin 31. The multi-chip module of this embodiment is
A plurality of semiconductor chips 23, 24 having different sizes or heights are mounted on the wiring board 2 to form an electronic circuit, and the radiation fins 31 are fixed to the wiring board 2.
Between the semiconductor chips 23, 24 and the radiation fin 31,
The heat conduction member 1 is installed. As in the embodiment shown in FIG. 4, the heat conduction member 1 has a plurality of tongue pieces 5a, 5b, 5c on one leaf spring 5 at positions corresponding to semiconductor chips.
Is provided to generate a pressing force on each of the semiconductor chips 23 and 24. The tongues 5a, 5b, and 5c have a structure in which each part of the leaf spring 5 that is a single metal plate is folded back in a U shape, or a structure in which a plurality of tongues are joined to a leaf spring that is a single metal plate. It can be one. According to the present embodiment, even in a module in which a plurality of semiconductor chips having different heights are mixed, the heat generated in all the semiconductor elements can be efficiently transferred to the heat radiation fins and efficiently cooled. Therefore, it is not necessary to individually attach a radiation fin to each semiconductor element, and a simple structure can be obtained.

FIG. 7 shows a modification. In this example, the radiation fin 31 and the heat conducting member 1 are integrated. A recess is formed at the bottom of the heat dissipation fin 3, and the heat conductive grease 4 and the leaf spring 5 having a plurality of tongue pieces are provided in this recess.
Is installed and sealed by the flexible film 6. The heat conductive grease 4, the leaf spring 5, and the flexible film 6 have the same configurations as those of the embodiments described above. According to this embodiment, even when the flatness of the surface of the heat generating member is not formed uniformly, or when a plurality of heat generating members are arranged side by side as shown in FIG. 6, for example, a simple structure is provided. It can be cooled simply by attaching one radiating fin.

In the embodiments shown in FIGS. 2 to 7, the example in which the heat conductive grease is applied is shown, but a liquid such as silicone oil having a high heat conductivity may be used.

A third embodiment of the present invention will be described with reference to FIGS. 8 to 10 are vertical cross-sectional views of the heat conducting member of this embodiment.

As can be seen from FIG. 8, the heat conducting member 1 is
A metal fin 41 is provided on a metal base having a contact surface that is as large as or larger than the area of the heat-generating electronic component 21.
The fin 41 is formed by molding so that a part of the fin 41 is inserted into the gel-like resin 10 having high thermal conductivity. The heat conducting member 1 is interposed between the heat generating electronic component 21 mounted on the wiring board 2 and the heat radiating member 3.
Here, a space 42 is formed between the gel-like resin 10 and the bottom portion of the fin 41 so that the deformation of the gel-like resin 10 can be absorbed. In the present embodiment, the fin 41 is molded so that a part of the fin 41 is inserted into the gel resin 10 having high thermal conductivity. Therefore, the distance between the heat generating electronic component 21 and the heat radiating member 3 is added from the outside. Even if it changes due to impact or thermal deformation, the gel-like resin is deformed in the shearing direction, so that it is easily deformed and has a spring property.
On the other hand, the conduction distance is shortened by configuring the fin 41 portion so as to enter into the gel-like resin 10. Since the fin 41 portion is provided, the area is expanded and the area contributing to heat conduction is increased. Since the fins 41 have much higher thermal conductivity than the gel resin 10, the heat is transmitted from the heat generating electronic component 21 to the heat radiating member 3 with a small thermal resistance, and the heat generating electronic component 21 can be cooled efficiently.

FIG. 9 shows a modification. This example has the same configuration as that of the embodiment shown in FIG. 8, except that metallic fins 41 are arranged on both sides of the gel-like resin 10, and the fins 41 are partially covered with the gel-like resin 10 from both sides of the gel-like resin 10. The fins 41 are formed so as to be engaged with each other. Also in this embodiment, the gel resin 10 and the fins 41 are used.
A space 42 is formed between the gel resin 1 and the bottom.
It can absorb 0 deformation. According to the present embodiment, the fins 41 have much higher thermal conductivity than the gel resin 10, so that the conduction distance is determined only by the gap between the fins, and the area contributing to heat conduction can be significantly increased. Therefore, heat can be transferred with a small heat resistance. As the shape of the fin 41 shown in FIGS. 8 and 9, a parallel plate fin or a pin-shaped fin is applied. Further, by forming the tips of the fins 41 at acute angles, it is possible to make the fins 41 highly flexible.

Although the thermal resistance can be reduced by reducing the gap between the fins 41,
You will lose flexibility. Therefore, by reducing the width of the fin (in the case of a pin-shaped fin, the diameter of the pin corresponds to this), the fact that the thermal conductivity of the fin is much larger than that of the gel-like resin is used to improve the thermal resistance. Can be very flexible without increasing. In addition,
Appropriate dimensions are selected according to the amount of heat generated by the heat-generating electronic components.

FIG. 10 shows a further modified example. This example
An uneven portion is formed on the heat dissipation member 3, and the uneven portion of the heat dissipation member 3 is formed so as to fit into the gel-like resin 10, and the gel-like resin 10 side is mounted on the wiring board 2.
It is pressed against 1. In the vicinity of the contact surface of the gel-like resin 10 with the heat-generating electronic component 21, the metal plate 1 spread in the contact surface direction.
1 is provided. Here, the uneven portion formed on the heat dissipation member 3 preferably has a sharp tip.

Also in this embodiment, as in the embodiment shown in FIGS. 8 and 9, even if the distance between the heat-generating electronic component 21 and the heat radiating member 3 changes due to external impact or thermal deformation,
Since the deformation of the gel-like resin 10 is the deformation of the uneven portion of the heat dissipation portion 3 in the shearing direction, it can be easily deformed and has a spring property. Further, since the metal surface is spread in the contact surface direction, the heat is diffused in the contact surface direction by the metal having high thermal conductivity. Therefore, the entire cross section of the heat conducting member in the contact surface direction contributes to heat transfer, the heat is transmitted from the heat generating electronic component to the heat radiating member with a simple structure and a small thermal resistance, and the heat generating electronic component is efficiently cooled.

A fourth embodiment of the present invention will be described with reference to FIG. FIG. 11 is a partial cross-sectional view of the electronic device of this embodiment.

Although this embodiment shows an example in which the heat conducting member is applied to the cooling of electronic equipment, in the present embodiment, among the wiring boards 2 constituting the electronic equipment, a semiconductor element having a particularly large heat generation amount. The electronic circuit part on which 21a and 21b are mounted is separated as another board 60, and both are electrically connected by a connector 61. A plurality of semiconductor elements can be mounted in the separated electronic circuit section in consideration of the operating speed of the circuit. The substrate 60 including the high heat generating portion is installed with the semiconductor element surface having a particularly large heat generation facing the metal casing 39.
The heat conducting member 1 is interposed between the semiconductor element surface and the metal casing 39. Although FIG. 11 shows an example in which the bottom surface of the housing 39 is used as the heat radiation surface, the top surface or the side surface of the housing 39 may be used as the heat radiation surface if the space is large.

According to the present embodiment, since the plurality of heat generating members and the metal casing wall are connected by the flexible heat conducting member, even if there is a variation in height among the heat generating members, the respective heat generating members are different. And the metal housing wall are efficiently and thermally connected. Further, due to the high thermal conductivity of the metal case, the heat is widely diffused to the case wall to obtain high heat dissipation performance, and the case wall is not locally heated to a high temperature.

In the embodiment described above, an example of cooling the heat-generating electronic components of the electronic equipment has been shown, but the invention can also be applied to cooling equipment having a heat-generating member other than the electronic equipment.

[0047]

As described above, according to the present invention,
Firstly, a heat conducting member capable of conducting heat with a small thermal resistance of a flexible structure that follows the fluctuation of the distance between the heat generating member and the heat radiating member and generates an appropriate pressing force, and an electronic device using the same. Can be provided.

Secondly, it is possible to provide a heat conducting member which has a flexible structure and conducts heat with a small heat resistance by diffusing the heat in the contact surface direction of the heat generating member, and a cooling device and electronic equipment using the heat conducting member.

Thirdly, the heat conducting member has flexibility because the fluid grease is filled in the flexible film bag. Further, since the leaf spring is enclosed, even if the distance between the heat generating member and the heat radiating member changes due to the pressing force of the leaf spring, it is possible to follow it and press it with an appropriate force. Further, since the leaf spring has a metal surface that spreads in the contact surface direction, heat is diffused in the contact surface direction due to the large thermal conductivity of the metal, and the entire cross section of the heat conducting member contributes to heat conduction. Thereby, heat can be transmitted from the heat generating member to the heat radiating member with a small heat resistance.

[0050]

[Brief description of drawings]

FIG. 1 is a perspective view of an electronic device that is a first embodiment of the present invention.

FIG. 2 is a vertical cross-sectional view of a heat conducting member of this embodiment.

FIG. 3 is a vertical cross-sectional view of a heat conducting member of this embodiment.

FIG. 4 is a vertical cross-sectional view of a heat conducting member of this embodiment.

FIG. 5 is a vertical cross-sectional view of a heat conducting member of this embodiment.

FIG. 6 is a vertical cross-sectional view of a heat conducting member showing a second embodiment of the present invention.

FIG. 7 is a vertical cross-sectional view of the heat conducting member of the present embodiment.

FIG. 8 is a vertical cross-sectional view of a heat conducting member showing a third embodiment of the present invention.

FIG. 9 is a vertical cross-sectional view of the heat conducting member of the present embodiment.

FIG. 10 is a vertical cross-sectional view of a heat conducting member of this embodiment.

FIG. 11 is a perspective view of an electronic device according to a fourth embodiment of the present invention.

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 1 ... Thermal conductive member, 2 ... Wiring board, 3 ... Heat dissipation member, 4 ... Thermal conductive grease, 5 ... Leaf spring, 6 ... Flexible film,
7 ... Fins, 10 ... Gel resin, 21 ... Heat-generating electronic components,
31, 41 ... Fins, 39 ... Metal casing.

Continued Front Page (72) Inventor Susumu Iwai 810 Shimoimaizumi, Ebina, Kanagawa Pref., Office Systems Division, Hitachi, Ltd.

Claims (16)

[Claims] 1. A heat-conducting member interposed between a heat-generating member and a heat-dissipating member for transmitting heat generated by the heat-generating member to the heat-dissipating member, wherein the heat-conducting member is formed in a bag shape. A heat-conducting member comprising a flexible film, a liquid medium having fluidity enclosed in the bag-shaped film, and a spring member for generating a pressing force against the film. 2. A heat conducting member which is interposed between a heat generating member and a heat radiating member and which transfers heat generated in the heat generating member to the heat radiating member, wherein the heat conducting member is formed in a bag shape. A flexible film, a liquid medium having a high thermal conductivity enclosed in the bag-shaped film, and a surface having a surface that spreads in a direction parallel to a contact surface that generates a pressing force against the film and the heating member. A heat-conducting member, comprising: a spring member having heat conductivity. 3. A heat conducting member which is interposed between a heat generating member and a heat radiating member and which transfers heat generated in the heat generating member to the heat radiating member, wherein the heat conducting member is formed in a bag shape. A liquid medium having a flexible film, having a high thermal conductivity, a fin having a base having a surface extending in a direction parallel to the contact surface with the heat generating member, and a high pressing force for the film. A heat-conducting member formed by enclosing a spring member having heat conductivity in the bag-shaped film. 4. A heat conducting member which is interposed between a heat generating member and a heat radiating member and which transfers heat generated in the heat generating member to the heat radiating member, the heat conducting member being formed on the heat radiating member. A liquid medium having fluidity and a spring member are housed in the concave portion and enclosed by a flexible film in the film, and the spring member is configured to generate a pressing force against the film. A heat conduction member characterized by the above. 5. A heat-conducting member interposed between a plurality of heat-generating members and a heat-dissipating member for transmitting heat generated by the plurality of heat-generating members to the heat-dissipating member, wherein the heat-conducting member is a plurality of the heat-conducting members. A flexible film formed in a bag shape that contacts the heat generating member, a liquid medium having high heat conductivity enclosed in the bag film, and the film corresponding to each of the plurality of heat generating members. And a spring member having a high thermal conductivity, the surface having a surface that spreads in a direction parallel to the contact surface with the heat generating member and that generates the pressing force. 6. A heat conducting member interposed between a heat generating member and a heat radiating member for transmitting heat generated in the heat generating member to the heat radiating member, the heat conducting member having a contact surface with the heat generating member. A heat-conducting member, characterized in that a part of a fin having a base whose surface extends in a parallel direction is inserted into a gel-like resin so that the bottom of the fin has a space. 7. A heat-conducting member interposed between a heat-generating member and a heat-dissipating member, for transmitting heat generated by the heat-generating member to the heat-dissipating member, the heat-conducting member being contained in a gel resin. Provide a metal plate having a surface extending in a direction parallel to the contact surface with
Further, the heat conducting member is characterized in that a part of the uneven portion formed on the heat dissipating member is inserted into the gel resin so that the bottom of the uneven portion has a space, and is molded. 8. The heat conducting member according to claim 1, wherein the spring member is a leaf spring and is provided with a plurality of tongue pieces. 9. The heat generating member according to claim 8, wherein a plurality of the heat generating members are mounted, and a plurality of tongue pieces of the spring member are formed at positions corresponding to the plurality of heat generating members. Heat conduction member. 10. The flexible film comprises a resin layer having a relatively high melting point on the outer side, an aluminum foil layer on the middle side, and a resin layer having a lower melting point than the resin of the outermost layer on the inner side in the form of a film. The heat conductive member according to claim 1, wherein the films are adhered to each other by heat fusion of the resin layer. 11. The heat conducting member according to claim 1, wherein the thickness of the heat conducting member is 5 mm or less. 12. The liquid medium is Z in silicone oil.
The heat conducting member according to claim 1, wherein nO, diamond, or metal-based particles are mixed. 13. The heat conducting member according to claim 6, wherein two fins are provided, the two fins are arranged in combination, and the gel resin is filled in the combined portion of the faces. 14. A heat-conducting member according to claim 2, wherein a heat-radiating member is provided with a spring member or a base having a surface extending in the parallel direction on the heat-generating member side. A cooling device characterized by being interposed between a member and a member. 15. An electronic device in which an electronic circuit board on which a plurality of semiconductor elements are mounted and peripheral devices thereof are housed in a housing having a metal surface, and the heat conducting member according to claim 1 is used. An electronic device characterized by being interposed between the semiconductor element and a metal surface of the housing. 16. An electronic device in which an electronic circuit board on which a plurality of semiconductor elements are mounted and peripheral devices thereof are housed in a metal housing, and a specific semiconductor element is mounted on the electronic circuit board on which the semiconductor elements are mounted. The heat conducting member according to any one of claims 1 to 13 is interposed between the specific semiconductor element and the metal wall surface of the housing. An electronic device characterized by the above.