JP7087126B1 - Electronics - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an electronic device and a cooling module provided with a cooling module capable of reducing the thickness while ensuring the cooling capacity. An electronic device includes a housing and a cooling module provided in the housing to cool a heating element. The cooling module is formed of a cooling fin, a blower fan that blows air to the cooling fin, and a carbon fiber reinforced resin in which carbon fiber is impregnated with a matrix resin, and is a plate that thermally connects the heating element and the cooling fin. It has a heat conductive member in the shape of. In the heat conductive member, the first portion on the heating element side is thermally connected to the heating element, and the second portion on the cooling fin side is thermally fixed to the cooling fin by sandwiching a metal layer in between. It is connected. In the blower fan, one surface of the fan housing that houses the impeller rotatably is closed by a heat conductive member. [Selection diagram] FIG. 4

Description

The present invention relates to an electronic device provided with a cooling module.

An electronic device such as a notebook PC houses a heating element such as a CPU. In such an electronic device, a cooling module is mounted in the housing, and the heat generated by the heating element can be diffused and dissipated to the outside.

Japanese Patent No. 6469183

The cooling module is generally configured to transfer the heat of the heating element to the cooling fins by a heat transport device such as a vapor chamber or a heat pipe, and discharge the heat to the outside of the housing by using a blower fan. Usually, the heat transfer device is laminated on the upper surface of the cooling fin and the blower fan adjacent thereto.

By the way, the blower fan is one of the thickest components of the cooling module. Therefore, the laminated portion of the heat transport device and the blower fan increases the thickness of the entire cooling module, and also hinders the thinning of the housing. However, if the blower fan is made too thin, the amount of blown air will decrease and the cooling performance of the cooling module will decrease.

The present invention has been made in consideration of the above-mentioned problems of the prior art, and an object of the present invention is to provide an electronic device provided with a cooling module capable of reducing the thickness while ensuring the cooling capacity.

The electronic device according to the first aspect of the present invention includes a housing, a heating element provided in the housing, and a cooling module provided in the housing to cool the heating element, and the cooling module. Is formed of a cooling fin, a blower fan that blows air to the cooling fin, and a carbon fiber reinforced resin in which carbon fibers are impregnated with a matrix resin, and thermally connects the heating element and the cooling fin. It has a plate-shaped heat conductive member, and the heat conductive member is thermally connected to the heat generating body by arranging the first portion on the heating body side so as to cover the heating body, and the cooling is performed. The second portion on the fin side is thermally connected to the cooling fin by being fixed to the cooling fin with a metal layer sandwiched between them, and the blower fan is one surface of a fan housing rotatably accommodating the impeller. Is closed by the heat conductive member.

According to one aspect of the present invention, it is possible to reduce the thickness while ensuring the cooling capacity.

FIG. 1 is a schematic plan view of an electronic device according to an embodiment as viewed from above. FIG. 2 is a bottom view schematically showing the internal structure of the housing. FIG. 3 is a bottom view of the cooling module. FIG. 4 is a schematic side sectional view of the cooling module and the motherboard. FIG. 5 is a schematic side sectional view of the cooling module according to the first modification. FIG. 6 is a schematic side sectional view of the cooling module according to the second modification. FIG. 7 is a schematic side sectional view of the cooling module according to the third modification. FIG. 8 is a schematic bottom view showing a configuration example in which the CPU, the cooling fins, and the blower fan are arranged side by side.

Hereinafter, suitable embodiments of the electronic device and the cooling module according to the present invention will be described in detail with reference to the accompanying drawings.

FIG. 1 is a schematic plan view of the electronic device 10 according to the embodiment, looking down from above. As shown in FIG. 1, the electronic device 10 is a clamshell notebook PC in which a display housing 12 and a housing 14 are relatively rotatably connected by a hinge 16. The electronic device according to the present invention may be a mobile phone, a smartphone, a portable game machine, or the like, in addition to a notebook PC.

The display housing 12 is a thin flat box body. A display 18 is mounted on the display housing 12. The display 18 has a display unit 18a for displaying an image and a touch panel unit 18b for touch operation. The display unit 18a is composed of, for example, an organic EL (OLED: Organic Light Emitting Diode) or a liquid crystal display. The touch panel unit 18b may be omitted.

Hereinafter, for the housing 14 and each component mounted on the housing 14, the front side is the front side, the back side is the rear side, and the width is based on the state in which the display housing 12 is opened and the display 18 is visually recognized as shown in FIG. The direction will be referred to as left and right, and the thickness direction will be referred to as up and down.

The housing 14 is a flat box body. A hinge 16 is connected to the rear end of the housing 14. The housing 14 is composed of an upper cover member 14a forming the upper surface and four peripheral side surfaces, and a lower cover member 14b forming the lower surface. A keyboard 20 and a touch pad 21 are provided on the upper surface of the housing 14. A cooling module 22 according to this embodiment is mounted inside the housing 14.

FIG. 2 is a bottom view schematically showing the internal structure of the housing 14. FIG. 2 is a view of the inside of the housing 14 from the inner surface side of the upper cover member 14a with the lower cover member 14b removed.

As shown in FIG. 2, a motherboard 24, a battery device 26, various electronic components such as a display board 28 and a touch panel board 29, and a cooling module 22 are mounted inside the housing 14.

The battery device 26 is a rechargeable battery that serves as a power source for the electronic device 10. The display board 28 is a sub-board for controlling the image display on the display unit 18a. The display board 28 is electrically connected to the display unit 18a via the flexible board 28a extending between the housings 12 and 14. The touch panel board 29 is a sub-board for controlling the touch panel unit 18b. The touch panel substrate 29 is electrically connected to the touch panel portion 18b via the flexible substrate 29a extending between the housings 12 and 14. The display board 28 and the touch panel board 29 are arranged on the rear side of the motherboard 24 and are connected to the motherboard 24.

The motherboard 24 is a printed circuit board on which a CPU (Central Processing Unit) 30, a communication module 31, a DC / DC converter 32, an SSD (Solid State Drive) 33, and the like are mounted. The motherboard 24 is arranged below the keyboard 20 and is screwed to the bottom surface of the keyboard 20 and the top cover member 14a. In the motherboard 24, the upper surface 24a serves as a mounting surface for the upper cover member 14a, and the lower surface 24b serves as a mounting surface for electronic components such as the CPU 30 and the communication module 31. Some of the electronic components may be mounted on the upper surface 24a. The motherboard 24 has a substantially T-shape in a plan view, and extends to the left and right at the rear of the housing 14.

The CPU 30 performs operations related to the main control and processing of the electronic device 10. The CPU 30 is a heating element having the largest amount of heat generated among the electronic components mounted in the housing 14. The communication module 31 is a device that processes information for wireless communication transmitted and received via an antenna (not shown) mounted on the display housing 12 and the housing 14. The DC / DC converter 32 converts the voltage of the DC power supplied from the battery device 26 into the voltage required for each electronic component such as the CPU 30. The SSD 33 is a storage device using a semiconductor memory. The communication module 31, the DC / DC converter 32, and the SSD 33 are heating elements having a heat generation amount next to that of the CPU 30. On the motherboard 24, the CPU 30, the DC / DC converter 32, and the SSD 33 are arranged side by side in a substantially horizontal row, and the communication module 31 is arranged on the front side of the CPU 30. Needless to say, the arrangement of the CPU 30 and the like can be changed as appropriate.

The cooling module 22 is a cooling device that absorbs and diffuses heat generated by a heating element such as a CPU 30, a communication module 31, a DC / DC converter 32, and an SSD 33, and further discharges the heat to the outside of the housing 14. Of course, the electronic component to be cooled of the cooling module 22 may be other than the CPU 30, the communication module 31, the DC / DC converter 32, and the SSD 33, and for example, various arithmetic units such as a GPU (Graphics Processing Unit) and images for a camera. Various heating elements such as chips and parts that generate heat during the operation of the electronic device 10 can be exemplified.

FIG. 3 is a bottom view of the cooling module 22. FIG. 4 is a schematic side sectional view of the cooling module 22 and the motherboard 24. In FIG. 4, in order to clarify the function of the cooling module 22, the cooling fins 38 and the blower fan 39 are shown side by side in the left-right direction, and the communication module 31 is shown side by side on the left side of the CPU 30.

As shown in FIGS. 2 to 4, the cooling module 22 includes a heat conductive member 34, a metal plate 36 integrally formed with a metal frame 35, a heat diffusion member 37, a cooling fin 38, and a blower fan 39. To prepare for.

First, the heat conductive member 34 is a heat conductive plate that extends between the CPU 30 and the cooling fins 38 and transports the heat from the CPU 30 to the cooling fins 38. The heat conductive member 34 has, for example, a substantially crank shape in a plan view. The heat conductive member 34 is a plate-shaped member formed of a carbon fiber reinforced resin in which a carbon fiber 34a is impregnated with a matrix resin, for example, a thermoplastic resin such as an epoxy resin or a thermosetting resin. The heat conductive member 34 of the present embodiment is formed of, for example, a pitch-based carbon fiber reinforced resin using pitch-based carbon fiber 34a made from coal tar pitch or petroleum pitch. Pitch-based carbon fiber reinforced resin has high rigidity and has the characteristic that it is not easily deformed even if the plate thickness is thin.

The carbon fibers 34a are arranged along the direction in which the fiber direction is directed from the CPU 30 toward the cooling fins 38. The straight line shown by the broken line in FIGS. 3 and 4 schematically shows the arrangement of the carbon fibers 34a. In this configuration example, since the cooling fin 38 is located on the rear right side when viewed from the CPU 30, the fiber axis of the carbon fiber 34a is along a direction gradually inclined to the left side from the rear to the front. For example, as shown in FIG. 8, in a configuration in which the CPU 30 is arranged side by side with the cooling fins 38 and the blower fan 39, the carbon fibers 34a are arranged so as to extend along the left-right direction.

In the heat conductive member 34, the first portion 34b on the CPU 30 side is arranged so as to cover the CPU 30, and the second portion 34c on the cooling fin 38 side is joined to the lower surface of the cooling fin 38. The heat conductive member 34 functions as a cover plate in which the third portion 34d between the first portion 34b and the second portion 34c closes one surface of the blower fan 39.

The first portion 34b is thermally connected to the CPU 30 with the metal plate 36 and the heat receiving member 30a interposed therebetween. The heat receiving member 30a is a small plate made of a metal having a high thermal conductivity such as copper or aluminum. The heat receiving member 30a may be omitted. The CPU 30 is connected to a position where the heat conductive member 34 and the metal plate 36 overlap with the heat conductive member 34 in the stacking direction (vertical direction).

The second portion 34c is fixed to the cooling fin 38 with the metal layer 40 interposed therebetween. The metal layer 40 is a thin layer made of a metal having a high thermal conductivity such as copper or aluminum. The metal layer 40 is formed on the upper surface 34e of the heat conductive member 34 by, for example, attaching a metal film, metal vapor deposition, metal coating, or the like. The metal layer 40 is an intermediate member for firmly fixing the cooling fins 38 to the upper surface 34e of the heat conductive member 34 made of the carbon fiber reinforced resin. In the configuration example shown in FIG. 4, the metal layer 40 is formed on a part of the upper surface 34e of the heat conductive member 34, that is, a portion where the cooling fin 38 and the blower fan 39 are fixed.

Next, the metal plate 36 is a plate formed of a metal having a high thermal conductivity such as aluminum, copper, or stainless steel. The metal plate 36 extends in the left-right direction and has a larger outer shape than the heat conductive member 34 and the heat diffusion member 37. The metal plate 36 is a support member for connecting the CPU 30 and the heat diffusion member 37 to the heat conduction member 34. The right side portion of the lower surface 36a of the metal plate 36 is fixed to the upper surface 34e of the heat conductive member 34. Since the metal plate 36 abuts on the heat conductive member 34 with a relatively large surface area, it can be fixed to the heat conductive member 34 by using, for example, a heat conductive adhesive or double-sided tape. The CPU 30 (heat receiving member 30a) and the heat diffusion member 37 are fixed to the upper surface 36b of the metal plate 36. By connecting the heat receiving member 30a to the metal plate 36, the heat receiving member 30a can be connected to the heat conductive member 34 made of carbon fiber reinforced resin with high heat transfer efficiency.

The metal frame 35 is a part of the metal plate 36, and the metal plate 36 is formed in a portion protruding from the outer edge portion of the heat conductive member 34. The metal frame 35 is provided so as to surround the left edge portion and the leading edge portion of the first portion 34b of the heat conductive member 34 in a plan view, and has a substantially crank shape in a plan view. The metal frame 35 is a portion that supports the heat diffusion member 37. The metal frame 35 has cutout holes 35a formed in various places of the metal plate 36 for weight reduction, forming a grid pattern.

Next, the heat diffusion member 37 is a member for cooling the communication module 31, the DC / DC converter 32, and the SSD 33, which are heating elements next to the CPU 30. The heat diffusion member 37 extends over substantially the entire surface of the metal frame 35 portion and a part of the portion that overlaps the heat conductive member 34 in the vertical direction in the upper surface 36b of the metal plate 36. It has a crank shape. The heat diffusion member 37 is fixed to the upper surface 36b with an adhesive, double-sided tape, or the like. The heat diffusion member 37 may be fixed on the lower surface 36a of the metal plate 36 (metal frame 35) so as to be aligned with the heat conduction member 34.

The heat diffusion member 37 is formed by melting a resin containing a carbon isotope containing graphene (including, for example, graphite, carbon nanotubes, fullerenes, etc.), heating and compressing the resin, and curing the resin into a plate shape. be. That is, the heat diffusion member 37 has high thermal conductivity, but is slightly fragile and has low strength. Therefore, the heat diffusion member 37 is entirely supported and reinforced by the metal frame 35. The heat diffusion member 37 may be made of a metal such as copper or aluminum as long as it is made of a material having high thermal conductivity. The heat diffusion member 37 is arranged so as to cover the communication module 31, the DC / DC converter 32, the SSD 33, and the like.

Next, the cooling fins 38 are arranged facing the exhaust port formed on the outer wall (rear wall in the present embodiment) of the housing 14. The cooling fin 38 is formed by forming a plurality of slits penetrating in and out of the housing 14 in a block of metal having high thermal conductivity such as aluminum, copper, or stainless steel.

As described above, the cooling fins 38 are fixed to the second portion 34c of the heat conductive member 34 via the metal layer 40. The heat conductive member 34 made of the carbon fiber reinforced resin has a matrix resin exposed on the surface including the upper surface 34e. Therefore, it is difficult to weld the metal cooling fin 38 to the upper surface 34e with the original material as it is. Therefore, the cooling fins 38 are firmly fixed to the upper surface 34e of the heat conductive member 34 by being joined to the metal layer 40 by welding or the like.

Next, the blower fan 39 is attached to the upper surface 36b of the metal plate 36 at a position between the cooling fin 38 and the CPU 30 (heat receiving member 30a). The blower fan 39 is close to the cooling fins 38, and the air sucked from the inside of the housing 14 is discharged to the outside of the housing 14 through the slits of the cooling fins 38.

As shown in FIG. 4, the blower fan 39 has a substantially bathtub-shaped fan housing 39b in which the impeller 39a is rotatably accommodated and supported. Since the lower surface of the fan housing 39b is open, in the case of a general fan, this opening is closed with a metal cover plate. On the other hand, in the fan housing 39b of the present embodiment, the opening on the lower surface is closed by the third portion 34d of the heat conductive member 34. As a result, the blower fan 39 can be made thinner by the amount of the cover plate, or the impeller or the like can be made larger by the amount of the cover plate even if the thickness is the same. The fan housing 39b may not have a bathtub shape, but may have a configuration in which the upper surface opening of a ring-shaped plate orbiting the side surface is closed with a cover plate.

As described above, the cooling module 22 of the present embodiment includes a heat conductive member 34 that absorbs heat generated by the CPU 30, which is the largest heating element, and transports it to the cooling fins 38. That is, in the heat conductive member 34 made of carbon fiber reinforced resin, the first portion 34b is thermally connected to the CPU 30, and the second portion 34c is fixed to the cooling fin 38 via the metal layer 40. Therefore, the heat generated by the CPU 30 is transferred from the heat receiving member 30a to the heat conductive member 34 and efficiently transferred to the cooling fins 38. At this time, the heat conductive members 34 are arranged along the direction in which the fiber direction of the carbon fibers 34a is directed from the CPU 30 toward the cooling fins 38. Therefore, the heat conductive member 34 can carry out heat transport more efficiently. The arrow shown by the alternate long and short dash line in FIG. 4 schematically shows the heat transfer.

At this time, the cooling fins 38 are fixed to the heat conductive member 34 via the metal layer 40. Therefore, the metal cooling fins 38 can be fixed to the heat conductive member 34 made of the carbon fiber reinforced resin with high strength and high heat transfer coefficient. As a result, when the heat generated by the CPU 30 is transferred from the heat receiving member 30a to the heat conductive member 34, it is efficiently transferred to the cooling fins 38.

By the way, in the cooling module 22, the thermal conductivity of the heat conductive member 34 is about 300 (W / mK). The thermal conductivity of the graphene plate forming the heat diffusion member 37 is about 1600 (W / mK). When the metal plate 36 is copper, the thermal conductivity is about 400 (W / mK). That is, since the heat conductive member 34 is made of carbon fiber reinforced resin, the heat conductivity is lower than that of the heat diffusion member 37, a general heat pipe, or the like.

However, the heat conductive member 34 of the present embodiment also functions as a cover plate that closes the opening of the fan housing 39b of the blower fan 39 by the third portion 34d, in addition to the function as the heat transport means. Therefore, the heat conductive member 34 is required to have not only high thermal conductivity but also high strength as a cover plate. Therefore, in the present embodiment, by forming the heat conductive member 34 with a high-strength carbon fiber reinforced resin, both functions are compatible at a high level.

Here, the plate thickness of the heat conductive member 34 is, for example, 0.3 mm. The thickness of the metal layer 40 is, for example, 0.01 mm. The plate thickness of the metal plate 36 is, for example, 0.1 mm. Since the metal frame 35 is a part of the metal plate 36, its plate thickness is 0.1 mm. The plate thickness of the heat diffusion member 37 is, for example, 0.3 mm. The plate thickness of the blower fan 39 and the cooling fin 38 is, for example, 3 mm. That is, a cover plate having a thickness of about 0.3 mm is usually attached to such a blower fan having a plate thickness of about 3 mm. However, the cooling module 22 can eliminate the thickness of the cover plate by using the heat conductive member 34, which is a heat transport means, for the cover plate. As a result, if the cooling module 22 has the same plate thickness, the blower fan 39 can be made larger by the amount of the cover plate, or the blower fan 39 can be made thinner by the amount of the cover plate. As described above, the heat conductive member 34 contributes not only to the cooling module 22 but also to the thinning of the housing 14. Further, since the heat conductive member 34 is made of carbon fiber reinforced resin, it is advantageous in terms of weight reduction as compared with the metal cover plate.

In the cooling module 22 of the present embodiment, a heat diffusion member 37 is further provided on the upper surface 34e of the heat conduction member 34 via a metal plate 36, and another heating element (communication module 31 or the like) is attached to the heat diffusion member 37. Covering. As a result, the cooling module 22 can efficiently absorb the heat of not only the CPU 30 but also other heating elements such as the communication module 31 by the heat diffusion member 37, diffuse the heat, and dissipate the heat. Moreover, the heat diffusion member 37 partially overlaps with the heat conduction member 34 in the vertical direction with the metal plate 36 interposed therebetween. Therefore, a part of the heat of the communication module 31 or the like is efficiently transported to the cooling fins 38 via the heat conductive member 34, so that higher heat dissipation performance can be obtained.

FIG. 5 is a schematic side sectional view of the cooling module 22A according to the first modification. FIG. 5 is an enlarged view of only a portion having a configuration different from that of the cooling module 22 of FIG. 4, and the same applies to FIGS. 6 and 7.

The cooling module 22A shown in FIG. 5 is provided so that the metal layer 40 covers substantially the entire surface of the upper surface 34e of the heat conductive member 34. As a result, the metal plate 36 can be joined to the metal layer 40 by welding or the like. Like the cooling module 22A shown in FIG. 5, the heat conductive member 34 may include a metal layer 41 that covers the lower surface 34f thereof. The metal layer 41 may have the same structure as the metal layer 40. As a result, at the time of manufacture of the cooling module 22A, the metal layer 40 can be easily formed by applying metal vapor deposition or metal coating to the entire outer surface of the heat conductive member 34. Of course, in the cooling module 22A shown in FIG. 5, the metal layer 41 may be omitted (see also the cooling module 22C shown in FIG. 7).

FIG. 6 is a schematic side sectional view of the cooling module 22B according to the second modification.

The cooling module 22B shown in FIG. 6 is provided only in a portion where the metal layer 40 overlaps with the cooling fins 38. That is, in the blower fan 39, the lower surface opening of the fan housing 39b is directly closed by the upper surface 34e of the heat conductive member 34. In this cooling module 22B, since the metal layer 40 does not intervene between the blower fan 39 and the heat conductive member 34, the blower fan 39 can be made thinner or larger by the thickness of the metal layer 40. It will be possible.

FIG. 7 is a schematic side sectional view of the cooling module 22C according to the third modification.

The cooling module 22C shown in FIG. 7 does not include the metal plate 36 (metal frame 35) and the heat diffusion member 37, or is configured to be separated from the heat conduction member 34. Similar to the cooling module 22A shown in FIG. 5, the cooling module 22C is provided so that the metal layer 40 covers substantially the entire surface of the upper surface 34e of the heat conductive member 34. The heat receiving member 30a of the CPU 30 is connected to the metal layer 40. That is, the heat receiving member 30a can be connected to the heat conductive member 34 made of carbon fiber reinforced resin with high heat transfer efficiency by being connected to the metal layer 40.

It should be noted that the present invention is not limited to the above-described embodiment, and of course, the present invention can be freely changed without departing from the gist of the present invention.

10 Electronic equipment 12 Display housing 14 Housing 22, 22A-22C Cooling module 30 CPU
31 Communication module 32 DC / DC converter 33 SSD
34 Heat conduction member 36 Metal plate 37 Heat diffusion member 38 Cooling fin 39 Blower fan 40, 41 Metal layer

Claims (2)

It ’s an electronic device,
With the housing
A heating element provided in the housing and
A cooling module provided in the housing and cooling the heating element,
Equipped with
The cooling module is
With cooling fins
A blower fan that blows air to the cooling fins,
A plate-shaped heat conductive member formed of a carbon fiber reinforced resin in which carbon fibers are impregnated with a matrix resin and thermally connecting between the heating element and the cooling fins.
Have,
The heat conductive member is thermally connected to the heating element by arranging the first portion on the heating element side so as to cover the heating element, and the second portion on the cooling fin side has a metal layer in between. By sandwiching and fixing to the cooling fin, it is thermally connected to the cooling fin.
In the blower fan, one surface of the fan housing that rotatably accommodates the impeller is closed by the heat conductive member.
A second heating element is further provided in the housing.
The cooling module further
A metal plate fixed to the same surface as the cooling fins with respect to the heat conductive member,
A plate-shaped heat diffusion member fixed to the fixed surface of the metal plate to the heat conductive member or the back surface thereof and arranged so as to cover the second heating element.
Have,
The heat diffusion member partially overlaps with the heat conduction member in the stacking direction of the heat conduction member and the metal plate.
The heating element is characterized in that it is connected to the back surface of the metal plate with respect to the heat conductive member with a heat receiving member sandwiched between them, and overlaps with the heat conductive member in the stacking direction. Electronic equipment. The electronic device according to claim 1.
The heat conductive member is an electronic device characterized in that the fiber direction of the carbon fiber is along the direction from the first portion to the second portion.

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