JP2004221604A - Cooling device - Google Patents

Abstract

An object of the present invention is to provide a cooling device excellent in heat radiation performance for cooling various electronic components such as semiconductor elements housed in a housing of a personal computer, especially a notebook personal computer.
The heat pipe includes a heat pipe thermally connected to a heat generating component, and a heat radiating section including a fan and a fin portion adjacent to the heat pipe or connected by a duct. The heat radiation side 100 of the heat pipe 10 is connected to the fin portion 20 so as to cross the direction in which exhaust gas passes through the fin portion 20, and a part of the heat radiation portion 40 including the heat pipe 10 is connected to the fan 30. The cooling device 70 located above the air suction port.
[Selection diagram] Fig. 1

Description

  The present invention relates to a cooling device for cooling various electronic components such as semiconductor devices housed in a housing of a personal computer, especially a notebook personal computer.

  2. Description of the Related Art In recent years, in various electric and electronic devices such as personal computers, cooling of a semiconductor element and the like provided therein has attracted attention as an important technical problem. Various methods are known for cooling a heat-generating component such as a semiconductor element provided in a housing. For example, as a method for cooling various components provided inside an electric / electronic device, there is a forced air cooling system using a fan. This is a method in which forced air cooling is performed by introducing and exhausting outside air into a housing of an electric / electronic device using a fan.

  Such a method has an advantage that the internal components are collectively cooled by suppressing a rise in the ambient temperature in the housing, but the cooling of specific components, that is, components that particularly require cooling is likely to be insufficient. In recent years, electric and electronic devices have also been reduced in size, and the internal space of the housing has been increasingly restricted. As described above, when the internal space is limited, it is difficult to realize a sufficient cooling function by the forced air cooling system as described above.

  Therefore, a method of attaching the fan 34 to a specific heat-generating component 50 that needs to be cooled in an electric / electronic device 90 (for example, a notebook personal computer) as shown in FIG. Have been. There is also known a method of arranging a heat sink 350 between a heat generating component 50 and a fan 35 in an electric / electronic device 91 as shown in FIG. According to such a method, there is an advantage that a heat-generating component requiring cooling can be efficiently cooled.

  In addition, a system that does not use a fan as shown in FIG. 10 is also known (Patent Document 2). This cooling method includes a metal plate 83 and a heat pipe 16, and the heat of the heat generating component 50 is transmitted to the metal plate 83 and radiated. The heat pipe 16 plays a role of dispersing the heat of the heat generating component 50 to a wide area of the metal plate 83.

JP-A-3-096258 JP-A-8-255858

  Each of the cooling methods shown in FIGS. 8 to 10 is effective, but it is not easy to achieve higher cooling performance. In the cooling method as shown in FIG. 10, it is difficult to increase the amount of heat radiation from the metal plate 83. Also in the cooling method as shown in FIGS. 8 and 9, since electric and electronic devices tend to be downsized, convection of air by the fans 34 and 35 does not easily occur, and thus it is difficult to increase the air volume by the fans 34 and 35. . Further, since the temperature of the air sucked by the fans 34 and 35 is increased, it is difficult to expect a large cooling effect.

  In addition, as shown in FIGS. 8 and 9, when the fans 34 and 35 are arranged close to the heat-generating components 50 and 50, there is a problem that dust and dirt easily accumulate on the heat-generating components 50 and 50. For example, when the heat generating components 50, 50 are semiconductor elements, there is a problem that if dust or dust accumulates on the circuit board, it may cause a trouble such as an electric short circuit.

  Therefore, recently, as shown in FIG. 7, a method has been proposed and put to practical use in which the heat generating component 50 and the fan 30 are separated to some extent, and heat is transferred using the heat pipe 15 between the heat generating component 50 and the fan 30. In this drawing, the heat of the heat generating component 50 is once received by the heat transfer block 60, and the heat is further transmitted to the heat pipe 15 and transferred to the fan 30. When the heat is dissipated from the fan 30, the heat generating component 50 is cooled. With this method, dust and dirt are less likely to be deposited on the heat-generating component than when the heat-generating component and the fan are close to each other.

  Further, the cooling method using the heat pipe 15 and the fan 30 as shown in FIG. 7 is also effective when the heat-generating component 50 cannot be arranged close to the fan 30 due to the mounting space of the heat-generating component 50. is there. That is, it is naturally desirable that the fan 30 is installed near the outer wall of the housing of the electric / electronic device, but the heat generating component 50 to be cooled is not always arranged near the outer wall of the housing. In such a case, if the cooling method shown in FIG. 7 is used, the degree of freedom in mounting and disposing the heat-generating component 50 is increased.

  In the case of the cooling method as shown in FIG. 7, in order to enhance the cooling performance of the heat generating component 50, the heat of the heat generating component 50 carried by the heat pipe 15 is radiated more efficiently at the fan 30. There was a need and therefore its development was desired.

  The invention has a heat pipe thermally connected to a heat-generating component, and a heat-dissipating portion including a fan and a fin portion adjacent to or connected to the heat pipe by a duct. The heat radiation side of the heat pipe is connected to the fin portion so as to cross the direction passing through the portion, and a part of the heat radiation portion including the heat pipe is located above the air suction port of the fan, It is a cooling device.

  In the cooling device according to the aspect of the invention, it is preferable that the housing that forms the fan and the fin unit be integrated.

  The cooling device of the present invention realizes excellent heat dissipation performance. In addition, by applying the heat pipe, it is not necessary to arrange the heat-generating component to be cooled and the fan close to each other, so that the fan can be arranged at a position where the heat radiation performance is further improved, and high heat radiation performance can be realized. Further, the accumulation of dust and dust by the fan can be suppressed. Thus, the cooling device of the present invention is excellent.

  An embodiment of the present invention will be described with reference to FIG. FIG. 1A is a perspective view, and FIG. 1A is a front view of a partial cross section. The illustrated cooling device 70 is provided in an electric or electronic device such as a personal computer. The heat generating component 50 to be cooled is connected to the heat transfer block 60. One end of the heat pipe 10 is joined or embedded in the heat transfer block 60. Reference numeral 101 in the figure denotes a heat absorbing side of the heat pipe 10.

  The heat absorbed from the heat absorbing side 101 of the heat pipe 10 is transmitted along the longitudinal direction of the heat pipe 10 and is radiated by the heat radiating portion 100 (FIG. 1A). The radiator 40, which is provided with the fins 20 in close proximity to the fan 30, allows the air sucked from above the fan 30 to pass through the fin element 201 of the fin 20, which is the side surface of the fan 30, as shown in the figure. The air flows so as to be exhausted.

  The fin unit 20 is preferably covered with covers 202 and 203 except for the inlet side 204 and the outlet side 205 of the air sent from the fan 30 (see FIG. 1A). The fin portion 20 may be formed by covering a fin element 201 made of, for example, a corrugated fin formed by corrugating an aluminum sheet with aluminum covers 202 and 203. The fin portion 20 is provided immediately after the outlet of the fan 30, and the wind passes through the fin element 201 at high speed and is discharged.

  The heat radiation side 100 of the heat pipe 10 is connected to the fin portion 20 so as to cross the direction in which exhaust air from the fan 30 passes through the fin portion 20. In the example of this figure, the heat radiation side 100 of the heat pipe 10 is fixed using the cover 203 on the upper surface.

  The cooling device 70 having the above-described configuration is provided in an electric / electronic device such as a personal computer as described above. Most of the heat of the heat generating component 50 passes through the heat transfer block 60 and moves to the heat radiating section 40 by the heat pipe 10 where the heat is radiated.

  Since the heat radiation side 100 of the heat pipe 10 is connected to the fin portion 20 so as to traverse the direction in which the exhaust air from the fan 30 passes through the fin 20, the heat radiation side 100 Heat is transmitted efficiently. Although heat is also transmitted to the covers 202 and 203, these covers 202 and 203 are preferably formed of aluminum having good heat conductivity. In addition, it is more preferable that the housing 32 of the fan 30 and the fin portion 20 be integrated, for example, because the heat transfer area of the heat radiating portion 40 is increased.

  In the heat radiating portion 40, the wind sent from the fan 30 passes through the fin portion 20 at a high speed, so that the heat transferred to the heat radiating portion 40 by the heat pipe 10 is effectively radiated. Thus, the heat generating component 50 can be cooled with high cooling performance.

  Further, since the cooling device 70 of the present invention transfers the heat of the heat generating component 50 to be cooled to the heat radiating unit 40 by the heat pipe 10 and radiates the heat, the heat generating component 50 can be set by appropriately setting the route of the heat pipe 10. There is an advantage that the degree of freedom in designing the position of the heat radiating section 40 and the position of the heat radiating section 40 is increased.

  The forced circulation of air by the fan 30 constituting the heat radiating portion 40 can cause dust and dirt to accumulate on the peripheral portion thereof. However, as in the cooling device 70 shown in FIG. It is desirable to place them apart from each other to a certain extent because the accumulation of dust and dust on the heat-generating component 50 is suppressed.

Note that it is desirable to secure a certain space in front of the air suction port 31 of the fan 30 in order to efficiently suck air. Although h shown in FIG. 1 (a) is a gap constituting the space, if the heat pipe 10 is arranged in this gap space, space efficiency will be excellent. Therefore, the connection between the heat pipe 10 and the fin portion 20 is preferably located above the air suction port of the fan 30.

The present invention will be described based on examples.
Example 1
A cooling device 70 having a configuration as shown in FIG. 1 was prepared. In this embodiment, a rubber heater having a size of 20 mm × 20 mm was attached in place of the heat-generating component 50. Each of the housings constituting the fin portion 20 and the fan 30 is made of aluminum having excellent thermal conductivity. The heat transfer block 60 is also made of aluminum. Now, with the fan 30 operating at the rated voltage, the rubber heater was energized with a constant power of 8 W or 12 W to measure the thermal resistance.

The thermal resistance was measured by measuring the temperature at the position indicated by ★ in FIG. 1 (A) (at a position approximately 5 mm from the rubber heater, such as being attached to the heat-generating component 50) and the temperature of the air blown by the fan 30. The difference was calculated as the value divided by the heat input. Table 1 shows the results.

  As a comparative example, as shown in FIG. 6 (heating parts are not shown), the thermal resistance was measured in the same manner as described above for an example in which the heat pipe 15 was attached to the fan 30. In the above-described embodiment of the present invention, an L-shaped heat pipe 10 is used as the heat pipe 10 and its heat radiation side is attached to the fin portion 20 so as to cross the direction in which exhaust air from the fan 30 passes through the fin portion 20. However, in the comparative example as shown in FIG. 6, a linear heat pipe 15 was used and attached to the fan 30. The results are also shown in Table 1.

  It can be seen from Table 1 that the example of the present invention is a cooling device that has significantly lower thermal resistance than the comparative example and can achieve excellent heat dissipation performance.

Example 2
A cooling device 71 having a configuration as shown in FIG. 2 was prepared. Illustration of the heat generating component is omitted. The heat transfer block 60 and the radiator 40 (the fan 30 and the fins 20) are the same as in the example of FIG. 1, but the heat transfer block 60 is attached to the heat pipe 11 not at one end but at substantially the center. A heat radiating plate 80 was attached to the heat pipe 11 on the side opposite to the heat radiating portion 40. Reference numeral 81 in the figure denotes a mounting bracket.

  In the case of this example of the present invention, in addition to the heat radiation at the heat radiation part 40 provided with the fan 30, there is also the heat radiation by the heat radiation plate 80, so that a higher heat radiation performance is realized.

  Further, the operation of the fan 30 can be stopped when the amount of heat radiated by the heat radiating plate 80 is sufficiently large, and the operating load of the fan 30 can be reduced. For example, a system that controls the operation of the fan 30 to start when the temperature of a heat-generating component (not shown) (connected to the heat transfer block 60) becomes equal to or higher than a predetermined temperature may be adopted. This extends the life of the fan 30 and also contributes to a reduction in power costs. When the cooling device 71 is applied to, for example, a notebook computer, the heat radiation plate 80 is preferably provided below the keyboard.

  By the way, it is desirable to secure a certain space in front of the suction port 31 of the fan 30 in order to efficiently suck air. H shown in FIG. 1A is a gap constituting the space. The same thermal resistance measurement as in Example 1 (power supplied to the rubber heater was 12 W) was performed in Example 2, but the size of the gap h was changed. Table 2 shows the results.

表２の結果から、吸い込み口の隙間ｈが１ｍｍのときに比べ、３ｍｍのときは熱抵抗が０．２℃／Ｗ程度低い値になった。これは実際の発熱部品の温度差に換算すると２．５℃程度に相当する。従って、隙間ｈはある程度確保することが放熱性能の観点で望ましいことが判る。尚、ヒートパイプ１１として、例えば径３ｍｍ程度のものを用いたとすると、そのヒートパイプ１１の配置スペースとして、この隙間を利用するとスペース効率の観点で望ましい。

From the results in Table 2, when the gap h between the suction ports was 1 mm, the thermal resistance was about 0.2 ° C./W lower when the gap was 3 mm. This is equivalent to about 2.5 ° C. in terms of the actual temperature difference between the heat-generating components. Therefore, it is understood that it is desirable to secure the gap h to some extent from the viewpoint of heat radiation performance. When a heat pipe 11 having a diameter of, for example, about 3 mm is used, it is desirable to use the gap as a space for disposing the heat pipe 11 from the viewpoint of space efficiency.

  Although not shown, if a heat pipe is separately attached to the heat radiating plate 80 to improve the heat uniformity, or if a flat heat pipe is used instead of the heat radiating plate 80, the heat radiating property is further improved.

Example 3
A third embodiment is an example in which the cooling device 71 of the second embodiment shown in FIG. 2 is improved and a heat radiating plate 82 extending to the fan 30 and the fin portion 20 is applied (see FIG. 3). The heat pipe 12 was fixed by a structure sandwiched between the heat transfer block 61 and the heat dissipation plate 82. Further, the heat pipe 12 crosses the heat dissipation plate 82 from below to above. Although not shown, as the fin element of the fin portion 20, an offset fin made of three layers made of aluminum was applied. When the heat radiation performance of the cooling device 72 was examined, it was confirmed that higher heat radiation performance was realized by applying the heat radiation plate 82 extending to the fan 30 and the fin portion 20.

  The heat dissipation plates 81 and 82 in the second and third embodiments described above can not only enhance the heat dissipation performance but also have a function as an electromagnetic shield in some cases.

Example 4
In the above embodiment, the direction of exhaust by the fan is one direction, but this direction may be multiple directions. FIGS. 4 and 5 show a case where the heat pipes are arranged in two directions. In this case, as shown in FIG. Also, as shown in FIG. 5, separate heat pipes 14, 140 can be attached to the fin portions 22, 220 in each direction.

1A and 1B are a perspective view and a partial cross-sectional front view illustrating an example of a configuration of a cooling device according to the present invention. It is a perspective view explaining other examples of the composition of the cooling device concerning the present invention. It is a perspective view explaining other examples of the composition of the cooling device concerning the present invention. 9 is a main part of another example of the configuration of the cooling device according to the present invention. 9 is a main part of another example of the configuration of the cooling device according to the present invention. It is a perspective view explaining the example of composition of the cooling device of a comparative example. It is a perspective view explaining the example of a structure of the conventional cooling device. It is a perspective view explaining the example of a structure of the conventional cooling device. It is a perspective view explaining the example of a structure of the conventional cooling device. It is a perspective view explaining the example of a structure of the conventional cooling device.

Explanation of reference numerals

REFERENCE SIGNS LIST 10 heat pipe 100 heat radiation side 101 heat absorption side 20 fin part 201 fin element 202 cover 203 cover 204 entry side 205 exit side 30 fan 31 suction port 32 housing 40 heat radiation part 50 heat generating component 60 heat transfer block 70 cooling device 11 heat pipe 80 Heat dissipating plate 71 Cooling device 12 Heat pipe 61 Heat transfer block 82 Heat dissipating plate 72 Cooling device 13 Heat pipe 21 Fin unit 31 Fan 14 Heat pipe 140 Heat pipe 22 Fin unit 220 Fin unit 32 Fan 15 Heat pipe 34 Fan 90 Electric / electronic equipment 35 fan 350 heat sink 91 electric / electronic device 16 heat pipe 83 metal plate 92 electric / electronic device

Claims (2)

A heat pipe thermally connected to the heat-generating component, and a heat radiator having a fan and a fin portion adjacent thereto or connected by a duct, and a direction in which exhaust air from the fan passes through the fin portion. A cooling device, wherein a heat radiating side of the heat pipe is connected to the fin portion so as to cross, and a part of a heat radiating portion including the heat pipe is located above an air suction port of the fan. The cooling device according to claim 1, wherein a housing constituting the fan and the fin portion are integrated.

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