JP6044157B2 - Cooling parts - Google Patents

Description

  Embodiments relate to a cooling component for cooling a heat-generating component.

  In electronic devices and the like, the amount of heat released from the CPU is increasing as the performance of the CPU is improved. On the other hand, electronic devices are required to be reduced in size and thickness. In addition to reducing the thickness of electronic components such as a CPU, a heat sink for cooling the CPU is also required to be reduced in thickness. Many heat sinks have heat radiation fins for releasing heat to the surrounding air. By increasing the heat radiation efficiency of the heat radiation fin, the heat radiation fin can be reduced in size and thickness.

  FIG. 1 is a perspective view showing an example of a heat sink having a conventional radiation fin. FIG. 2 is a perspective view showing the inside of the electronic device in which the heat sink shown in FIG. 1 is incorporated.

  A heat sink 1 shown in FIG. 1 includes a base plate 3 provided with a die plate 2 that comes into contact with a heat-generating component such as a CPU, a heat radiating fin 5, and a heat pipe 4 that connects the die plate 2 and the heat radiating fin 5. As shown in FIG. 2, the base plate 3 is attached to the circuit board 11 so that the die plate 2 is in contact with the upper surface of the CPU (cooled component) mounted on the circuit board 11 of the electronic device 10. In FIG. 2, since the CPU is covered with the die plate 2, it does not appear in the figure.

  The heat radiating fins 5 attached to the heat pipe 4 extending from the die plate 2 are attached to the chassis of the electronic device 10. A fan 13 is provided in the vicinity of the radiating fin 5, and the radiating fin 5 is air-cooled by an air flow from the fan 13. The radiating fins 5 are formed by arranging a large number of thin metal plates (fins) at a predetermined pitch, and the air from the fan 13 flows between the fins of the radiating fins 5 and is discharged outside the casing of the electronic device.

  2 is, for example, a personal computer, and a large number of functional components such as a memory 14, a hard disk drive 15, and an optical disk drive 16 are accommodated in a housing.

  In the electronic device 10 configured as described above, the heat radiating fins 5 are components that occupy a relatively large volume. Therefore, by improving the heat dissipation efficiency of the heat dissipation fin 5 and reducing the size of the heat dissipation fin 5, it is possible to contribute to the reduction in size and thickness of the electronic device 10. Alternatively, by using the radiation fins 5 of the same size, it is possible to cool the component to be cooled (here, the CPU) more efficiently and lower the temperature.

  Thus, it has been proposed to improve the heat dissipation efficiency by devising the fin shape and arrangement of the heat dissipation fins (see, for example, Patent Documents 1 to 3).

Japanese Patent Laid-Open No. 01-215098 JP 2003-86742 A Registration No. 3148593

  FIG. 3 is a side view of the radiation fin 5 shown in FIG. In the radiating fin 5 incorporated in the heat sink 1 shown in FIG. 1, heat to be released from the radiating fin 5 is supplied to the side 5a to which the heat pipe 4 is attached. The heat is transmitted through the fin 5b formed by a thin metal plate, and reaches the side 5c opposite to the side 5a to which the heat pipe 4 is attached. Since part of the heat is released around the fin 5b while being transmitted through the fin 5b, the temperature of the side 5a to which the heat pipe 4 is attached is the highest, and the side 5c opposite to the side 5a to which the heat pipe 4 is attached. Is lower than the temperature of the side 5a to which the heat pipe 4 is attached.

  Since the heat radiation amount (heat radiation efficiency) is proportional to the temperature difference, the heat radiation efficiency on the side 5c opposite to the side 5a to which the heat pipe 4 is attached is lower than the heat radiation efficiency on the side 5a to which the heat pipe 4 is attached.

  Therefore, if the amount of heat transferred to the opposite side 5c of the side 5a to which the heat pipe 4 is attached is increased, the temperature of the opposite side 5c of the side 5a to which the heat pipe 4 is attached can be raised. Thereby, the heat radiation efficiency in the opposite side 5c of the side 5a to which the heat pipe 4 is attached can be increased, and as a result, the heat radiation efficiency in the entire heat radiation fin 5 can also be increased.

  However, in the conventional radiating fin, the thickness of the fin 5b and the pitch of the fin 5b are determined to be optimum values that increase the radiating efficiency based on the entire volume of the radiating fin 5 and the air flow passing between the fins 5b. Yes. That is, it is not considered to efficiently transfer heat to the opposite side 5c of the side 5a to which the heat pipe 4 is attached as described above.

According to the embodiment, an endothermic member that absorbs heat from the component to be cooled;
The heat absorbing member dissipates heat absorbed by the heat absorbing member, and a heat dissipating member in which a plurality of first fins extending in parallel with each other are provided, and a part of the first fin includes the first fin have a greater thickness than other portions of the first fin, said first fin are aligned at a predetermined interval, that overlap in contact with the plurality of said first fin, said first fin A cooling part is provided in which a portion is formed and a second fin extending perpendicularly to the extending direction of the first fin is provided .

  By partially increasing the thickness of the fin, the amount of heat transmitted from the heat supply side to the opposite side of the heat dissipation member can be increased, and the heat dissipation efficiency of the entire heat dissipation member can be improved.

It is a perspective view of a heat sink. It is a perspective view which shows the inside of the electronic device incorporating the heat sink shown in FIG. It is a side view of a radiation fin. It is a perspective view of the heat sink by one Embodiment. FIG. 5 is a perspective view showing a part of the inside of the electronic device in which the heat sink shown in FIG. 4 is incorporated. It is a perspective view of a radiation fin. It is a front view of a radiation fin. It is an exploded view of the bent metal plate for forming a thick fin part. It is a figure which shows the result of having calculated | required the cooling performance of the radiation fin by simulation.

  Next, embodiments will be described with reference to the drawings.

  FIG. 4 is a perspective view of a heat sink (cooling component) according to an embodiment. FIG. 5 is a perspective view showing a part of the inside of the electronic device in which the heat sink shown in FIG. 4 is incorporated. 4 and 5, parts that are the same as the parts shown in FIGS. 1 and 2 are given the same reference numerals.

  The heat sink 20 shown in FIG. 4 includes a base plate 3 (support member) provided with a die plate 2 (heat absorbing member) that contacts a heat-generating component such as a CPU and absorbs heat, a heat radiating fin 30 (heat radiating member), a die It has the heat pipe 4 (heat transfer member) which connects the plate 2 and the radiation fin 30. As shown in FIG. 5, the base plate 3 is attached to the circuit board 11 so that the die plate 2 is in contact with the upper surface of the CPU (cooled component) mounted on the circuit board 11 of the electronic device 10. The base plate 3 is a substantially triangular metal plate, and the die plate 2 is supported at the center thereof. At three corners of the base plate 3, screw insertion portions 3a into which screws 6 are inserted are provided as attachment portions for fixing the base plate 3 and fixing the die plate 2 on the CPU. Note that. In FIG. 5, the CPU that is an example of the component to be cooled is not shown in the drawing because it is covered with the die plate 2.

  One end 4 a of the heat pipe 4, which is an example of a heat transfer member, is connected to the die plate 2 supported by the base plate 3. The other end 4 b of the heat pipe 4 is connected to the radiation fin 30. The heat radiating fins 30 to which the heat pipes 4 are attached are attached to the housing or chassis of the electronic device 10. A fan 13 is provided in the vicinity of the radiating fin 30, and the radiating fin 30 is air-cooled by an air flow from the fan 13. Air sent out from the fan 13 flows between the fins of the heat radiating fins 30 and is discharged outside the casing of the electronic device 10.

  Next, the radiation fin 30 according to the present embodiment will be described in more detail. FIG. 6 is a perspective view of the radiation fin 30. FIG. 7 is a front view of the radiation fin 30. The heat radiating fin 30 as an example of the heat radiating member has a substantially rectangular parallelepiped shape, and includes a first surface 30a and a second surface 30b opposite to the first surface 30a. A plurality of first fins 32 are arranged in parallel with each other at a predetermined interval between the first surface 30a and the second surface 30b.

In the present embodiment, the second fin 34 is formed so as to extend in a direction orthogonal to the first fin 32 at a substantially central position between the first surface 30a and the second surface 30b. Yes. As will be described later, the second fin 34 is a part provided to form a part having a large thickness in a part of the first fin 32, and a direction orthogonal to the extending direction of the first fin 32. Extend to. In other words, the second fin 34 is a necessary part for manufacturing reasons. The other end 4 b of the heat pipe 4 is connected to the first surface 30 a of the heat radiating fin 30 and transferred in the heat pipe 4. Heat is transmitted to the first surface 30a. Therefore, when viewed from the radiation fins 30, the first surface 30 a is a heat supply surface to which heat is supplied from the heat pipe 4. Of course, even the heat supply surface releases heat to the surrounding air from the first surface 30a.

  Heat is supplied to the first surface 30b of the heat radiating fin 30 through the first fin 32 and the second fin 34, and the heat is released to the surrounding air. Therefore, the second surface 30b becomes a heat release surface. A part of heat is transferred from the first fin 32 and the second fin 34 to the surrounding air while being transmitted through the first fin 32 and the second fin 34.

  In this embodiment, the radiation fin 30 is formed by overlapping and joining a plurality of bent metal plates. The heat dissipating fins formed by joining together a plurality of metal plates have a well-known configuration as shown in FIG. 1, and here, in particular, a description of a manufacturing method for forming heat dissipating fins having a substantially rectangular parallelepiped shape by connecting metal plates. Is omitted.

  As the plurality of metal plates forming the heat radiation fins 30, for example, a copper plate or an aluminum plate having a high thermal conductivity and a high heat transfer rate can be used. The metal plate for forming the heat radiating fins 30 is not limited to a copper plate or an aluminum plate, and various materials such as an iron plate, a steel plate, and a material obtained by plating them can be used.

  In the present embodiment, each of the first fins 32 is divided into a fin portion 32a on the first surface 30a side and a fin portion 32b on the second surface 30b side, and the fin portion 32a and the fin portion 32b are aligned. Thus, each of the first fins 32 is formed. Moreover, the thick fin part 32c is formed as a part which the several fin part 32a overlapped and joined. The thick fin portion 32c extends from the first surface 30a toward the second surface 30b and extends to approximately the center between the first surface 30a and the second surface 30b.

  From the tip of the thick fin portion 32c, the second fin 34 extends in a direction perpendicular to the second fin 34. The second fin corresponds to a portion where a metal plate for forming the first fin 32 is bent to form a fin portion 32c in which the fin portions 32a are overlapped and thickened.

  In the present embodiment, in order to increase the heat radiation efficiency of the heat radiation fins 30, for example, a 0.2 mm metal plate is used, and the distance between the metal plates and the metal plate (that is, the pitch of the aligned first fins 32) is, for example, 1. 5 mm. The thickness of the metal plate (i.e., the thickness of the fin) and the interval between the metal plates (i.e., the pitch of the fins) are set to values that increase heat dissipation due to the airflow flowing between the fins.

  Considering the thickness dimension and the interval dimension of the metal plate as described above, the fin portion 32c having a thickness corresponding to one pitch is formed. For this purpose, the metal plates are bent so that the eight metal plates overlap to form the fin portion 32c.

  FIG. 8 is an exploded view of the bent metal plate for forming the thick fin portion 32c. The eight metal plates for forming the thick fin portions 32 c are metal plates on which fin portions 32 b that are lower portions of the first fins 32 are formed. Each of the eight metal plates is bent at the upper end of the fin portion 32b in a direction perpendicular to the fin portion 32b, and further, the fin portion 32c is bent in the same direction as the fin portion 32b.

  Each of the eight metal plates is bent at a lower end of the fin portion 32b in a direction orthogonal to the fin portion 32b to form a flat portion 32d. When the metal plates are overlaid, the flat portion 32 d is connected to become a flat surface, and forms the second surface 30 b of the radiating fin 30.

  Three metal plates each forming the fin portion 32a are arranged on the left and right sides of the fin portion 32c. The upper end of the fin portion 32a is bent in a direction orthogonal to the fin portion 32a to form a flat portion 32e. In addition, the upper end of the rightmost metal plate forming the fin portion 32c is bent in a direction orthogonal to the fin portion 32c to form a flat portion 32f. The planar portion 32e and the planar portion 32f are connected to each other when the metal plates are overlapped to form a first surface 30a of the radiating fin 30.

  As shown in FIG. 8, by bending and joining metal plates that are bent, eight fin portions 32b are formed, and one thick fin portion 32c is formed on the center thereof, and the thick fins Radiating fins 30 each having three fin portions 32a formed on both sides of the portion 32c are formed. The radiating fin 30 shown in FIG. 6 is formed by connecting five radiating fins formed of a metal plate shown in FIG.

  As described above, in the present embodiment, since the thick fin portion 32c is formed by increasing the thickness of a part of the first fin 32, the heat transfer area by the first fin 32 increases, and more A large amount of heat can be moved from the first surface 30a side to the second surface 30b side. As a result, the temperature on the second surface 30b side of the radiating fin 30 rises and approaches the temperature on the first surface 30a side, and the heat radiation efficiency on the second surface 30b side increases. Therefore, the heat radiation efficiency of the entire heat radiation fin 30 is improved and more heat can be released, so that the cooling efficiency of the heat sink 20 is improved. Thereby, the heat sink 20 can be reduced in size and thickness.

  More heat can be moved from the first surface 30a side to the second surface side, not only by increasing the heat transfer area, but also by making a part of the first fin 32 thicker. Has contributed. In heat transfer characteristics of heat transmitted through the plate-shaped member, there is a characteristic that the amount of heat transfer is larger on the inner side than on the surface side in the cross section of the member. If the fin is thin, more heat is transmitted near the surface. However, if the fin is thick, more heat is transmitted on the inside (portion closer to the center in the cross section) than on the surface, and the amount of heat transfer increases accordingly. Therefore, for example, heat transfer in a state where eight fins are overlapped and joined rather than heat transfer in a state where the eight fins are separated from each other increases the heat transferred inside the fins, and thus the heat transfer as a whole. The amount of heat will increase. In the present embodiment, since the thick fin portion 32c is formed by overlapping the eight metal plates, the amount of heat transfer can be increased, and the heat dissipation efficiency can be improved accordingly.

  The thick fin portion 32c may be provided at any position in the extending direction of the first fin, but is preferably extended from the first surface 30a on the heat supply side for transmitting more heat. In the present embodiment, the thick fin portion 32c extends to a substantially central position between the first surface 30a and the second surface 30b, but is not limited to the center and may be set as appropriate. preferable. If the thick fin portion 32c is too long, the portion through which air passes is reduced, and the heat dissipation efficiency is reduced accordingly. Therefore, it is preferable to appropriately set the heat dissipation efficiency in consideration of the entire heat dissipation fin. The same applies to the thickness of the thick fin portion 32c. If the thickness is large, the heat transfer efficiency in the fin portion 32c increases, but the portion through which air passes decreases, and the heat dissipation efficiency decreases accordingly. Therefore, it is preferable to set the thickness of the thick fin portion 32 c as appropriate while considering the heat radiation efficiency of the entire heat radiation fin 30.

  The second fin 34 is connected to the plurality of fin portions 32b while extending in a direction orthogonal to the thick fin portion 32c. Thereby, the heat transmitted through the thick fin portion 32c can be dispersed to the plurality of fin portions 32b, and the heat transfer from the thick fin portion 32c to the second surface 30b via the fin portion 32b is further improved. Be efficient.

  The aluminum plate (A1050) is used as a material for forming the fins, and the heat conduction is simulated by the heat dissipating fins 5 shown in FIG. 1 and the heat dissipating fins 30 according to the present embodiment shown in FIG. 4 and FIG. The temperature of the 1st surface 30a and the temperature of the 2nd surface 30b used as a thermal radiation surface were compared. In the simulation, the heat from the 35 W CPU is transferred by the heat pipe 4 and supplied to the radiation fins. The temperature around the heat radiating fins was 35 ° C.

  As a result of the simulation, in the radiating fin 5 shown in FIG. 1, the temperature of the first surface 30a on the heat supply side is 61.1 ° C., and the temperature of the second surface 30b on the radiating side is 51.4 ° C. There was a temperature difference of 9.7 ° C. On the other hand, in the radiation fin 30 according to the present embodiment shown in FIGS. 4 and 6, the temperature of the first surface 30a on the heat supply side is 59.1 ° C., and the temperature of the second surface 30b on the heat dissipation side is It was 53.5 ° C., and it was found that the temperature difference was reduced to 5.6 ° C. That is, in the radiation fin 30 according to the present embodiment shown in FIGS. 4 and 6, the provision of the thick fin portion 32 c reduces the thermal resistance between the first surface 30 a and the second surface 30 b, and It is considered that a large amount of heat is transmitted from the first surface 30a to the second surface 30b, and the temperature difference is reduced.

  Here, the cooling performance in the case of using the radiation fin 5 shown in FIG. 1 and the case of using the radiation fin 30 according to the present embodiment shown in FIGS. FIG. 9 shows the result of the cooling performance obtained by simulation.

  In the simulation, the structure shown in FIG. 1 (conventional FIN) and the structure shown in FIG. 4 and FIG. 6 are used for the heat radiating fins made of three types of metal plates: a copper plate (C1100), an aluminum plate (A1050), and an aluminum plate (A5052). The cooling performance by (new structure FIN) was determined. And the improvement rate of the cooling performance in the structure (new structure FIN) shown in FIG.4 and FIG.6 with respect to the cooling performance in the structure (conventional FIN) shown in FIG. 1 was calculated | required. The temperature Ta around the radiating fin was 35 ° C., and a 35 W CPU was used as a component to be cooled.

  When the copper plate (C1100) was used, the improvement rate of the cooling performance was 1.4%, and the cooling performance with the structure (new structure FIN) shown in FIGS. 4 and 6 was improved. When the aluminum plate (A1050) was used, the improvement rate of the cooling performance was 4.0%, and the cooling performance with the structure (new structure FIN) shown in FIGS. 4 and 6 was greatly improved. Further, when the aluminum plate (A5052) was used, the improvement rate of the cooling performance reached 5.7%, and the cooling performance with the structure (new structure FIN) shown in FIGS. 4 and 6 was further improved. . Such an improvement in cooling performance is presumed to be an effect due to the provision of the thick fin portion 32c.

  As a modification of the above-described embodiment, for example, the above-described embodiment can be applied to a cooling component that is directly mounted on a component to be cooled instead of a heat pipe type cooling component. In this case, since the cooling component is directly attached to the component to be cooled, the heat transfer component becomes unnecessary.

As described above, the present specification discloses the following matters.
(Appendix 1)
An endothermic member that absorbs heat from the component to be cooled;
A heat dissipating member that dissipates heat absorbed by the heat absorbing member and that is provided with a plurality of first fins extending in parallel with each other;
A part of the first fin has a larger thickness than the other part of the first fin.
(Appendix 2)
The cooling component according to appendix 1,
A heat transfer member that transfers heat absorbed by the heat absorption member to the heat dissipation member;
A part of the first fin is a cooling component provided on the side where the heat transfer member is connected in the extending direction of the first fin.
(Appendix 3)
The cooling component according to appendix 1 or 2,
The cooling component in which the first fins are aligned at a predetermined interval, and a plurality of the first fins come into contact with each other and overlap to form the part of the first fin.
(Appendix 4)
The cooling part according to any one of appendices 1 to 3,
A cooling component provided with a second fin extending perpendicularly to the extending direction of the first fin.
(Appendix 5)
The cooling component according to appendix 4,
The second fin is a cooling component that extends perpendicular to the first fin at a position corresponding to the end of the part of the first fin.
(Appendix 6)
The cooling component according to appendix 4 or 5,
The first fin and the second fin are cooling parts formed by bending a metal plate.
(Appendix 7)
The cooling component according to any one of appendices 1 to 6,
The heat transfer member is a cooling component that is a heat pipe.
(Appendix 8)
The cooling part according to any one of appendices 1 to 7,
The heat absorbing member is a cooling component that is a heat conductive metal plate.
(Appendix 9)
The cooling component according to any one of appendices 1 to 8,
A support member for supporting the heat absorbing member;
The said support member is a cooling device which has an attachment part which fixes so that the state which made the said heat absorption member contact the said to-be-cooled component may be maintained.

2 die plate 3 base plate 3a screw insertion hole 4 heat pipe 6 screw 10 electronic device 11 circuit board 13 fan 20 heat sink 30 heat radiating fin 30a first surface 30b second surface 32 first fin 32a fin portion 32b fin portion 32c meat Thick fin part 34 Second fin

Claims (3)

An endothermic member that absorbs heat from the component to be cooled;
A heat dissipating member that dissipates heat absorbed by the heat absorbing member and that is provided with a plurality of first fins extending in parallel with each other;
Part of the first fin, have a greater thickness than other portions of said first fin,
The first fins are aligned at a predetermined interval, and a plurality of the first fins come into contact with each other to form the part of the first fins.
A cooling component provided with a second fin extending perpendicularly to the extending direction of the first fin . The cooling component according to claim 1,
A heat transfer member that transfers heat absorbed by the heat absorption member to the heat dissipation member;
Wherein a portion of the first fin, said first fin the heat cooling parts transfer member is provided on the side connected in the extending direction of the. The cooling component according to claim 1 or 2,
The first fin is the first part of a metal plate including a first part and a second part connected via a bent portion, and the second fin is the first part of the metal plate. The cooling part which is 2 parts.

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