JP2012243806A - Heat sink and electronic device using the same - Google Patents

Abstract

PROBLEM TO BE SOLVED: To reduce stagnation of air on a lateral face of a heat sink.SOLUTION: A heat sink 1 comprises: a heat dissipation member 15 which promotes the heat radiation from a heating element; and an air blower 2 which generates cooling air A to be circulated through the heat dissipation member 15. The air blower 2 is configured such that the cooling air A is circulated not only in the inside of an outer edge of the heat dissipation member 15 but also in the outside of the outer edge. A position X on a rotation shaft 12 of the air blower 2 is deviated from a center position Y of a cooling region located in the inside of the outer edge of the heat dissipation member 15.

Description

  The present invention relates to a heat sink for cooling a heating element mounted on an electronic device.

  In an electronic device such as a computer, a heat sink is used to cool a heating element such as a CPU. A general heat sink realizes a cooling action by forcibly convection of air by rotation of a fan or the like inside the electronic device.

  The heat sink according to Patent Document 1 is connected to the heat receiving part so as to form a first air flow path, and the heat from the heat receiving part is transferred to the first air flow path, with the object of increasing heat dissipation efficiency at a low cost. A first heat dissipating part that dissipates heat by air passing through the air, and a second air flow path that is spaced apart from the heat receiving part and into which the air in the first air flow path can flow in and is narrower than the first air flow path. And a second heat radiating portion connected to the first heat radiating portion and radiating heat from the first heat radiating portion.

  Further, Patent Documents 2 to 5 are disclosed as other prior arts related to a heat sink.

International Publication No. 2002/054490 Japanese Patent Laid-Open No. 2002-134973 JP 2003-282801 A JP 2007-172076 A JP 2009-076708 A

  FIG. 4 illustrates an internal configuration of an electronic device on which the heat sink 101 is mounted. The heat sink 101 according to this example is mounted on the mother board 103 in the tower type computer 102 and has a main purpose of cooling the main CPU 104. The motherboard 103 is fixed parallel to the side surface of the casing 105 (perpendicular to the ground). The heat sink 101 is disposed so as to cover the upper surface of the main CPU 104 and is fixed to the mother board 103. A graphic board 106 is fixed to the motherboard 103. The graphic board 106 is arranged perpendicular to the motherboard 103 (parallel to the ground). The graphic board 106 is equipped with a CPU 107 as a heating element.

  The heat sink 101 includes a blower unit 111 and a heat dissipation unit 112. The blower unit 111 includes a fan and the like, and generates cooling air in the direction of arrow B. The heat dissipation unit 112 includes fins and the like, and is thermally connected to the main CPU 104 through a member having high thermal conductivity. Cooling air generated by the blower unit 111 circulates inside the heat radiating unit 112 and is discharged outside the casing 105 via the exhaust unit 115.

  In the heat sink 101 shown in FIG. 4, all the intake air B <b> 1 sucked by the blower unit 111 is discharged into the heat radiating unit 112 and becomes cooling air B. With such a structure, there is a tendency for local air stagnation to occur in the side surface portion of the heat sink 101 with less air flow. For this reason, as in this example, when a heat generating element such as the graphic board 106 is present on the side surface of the heat sink 101, heat stagnation may occur in a portion indicated by a region S in FIG. 4.

  Such problems caused by local air stagnation cannot be solved even with the configurations disclosed in Patent Documents 1 to 5.

  Then, this invention makes it a subject to reduce the stagnation of the air in the side part of a heat sink.

  One aspect of the present invention includes a heat dissipating member for promoting heat dissipation of a heat generating element and a blower that generates cooling air flowing through the heat dissipating member. It is a heat sink comprised so that it may distribute | circulate not only inside but the said outer edge part.

  Another embodiment of the present invention is an electronic device including at least one heat generating element and the heat sink.

  According to the present invention, the cooling air generated by the blower circulates not only inside the heat radiating member but also outside thereof, so that the air fluidity at the side surface of the heat sink is improved. Thereby, even if a heat generating element is arrange | positioned at the side part of a heat sink, the stagnation of a heat | fever is prevented and sufficient cooling effect can be acquired.

It is a perspective view which shows the structure of the heat sink which concerns on Embodiment 1 of this invention. It is the perspective view which looked at the heat sink shown in FIG. 1 from diagonally right rear. It is a figure which shows the internal structure of the electronic device carrying the heat sink which concerns on Embodiment 1. FIG. It is a figure which illustrates the internal structure of the electronic device carrying a heat sink.

Embodiment 1
Embodiments of the present invention will be described below with reference to the drawings. 1 and 2 show the configuration of the heat sink 1 according to Embodiment 1 of the present invention. The heat sink 1 includes a blower unit 2, a heat radiating unit 3, and a fixed unit 4.

  The blower unit 2 includes a multiblade fan (hereinafter abbreviated as a fan) 11, a rotating shaft 12 to which the fan 11 is fixed, a driving mechanism (not shown) that rotates the rotating shaft 12, a fan guard 13, and the like. In the present embodiment, cooling fan is generated in the direction of arrow A as the fan 11 rotates.

  The heat radiating unit 3 includes a plurality of fins 15, heat conducting members 16, 17 and the like. Each fin 15 is made of a material having a high thermal conductivity such as aluminum and has a laminated structure. A space is formed between the fins 15, and the cooling air from the blower unit 2 passes through the space. The heat conductive members 16 and 17 thermally connect the heat generating elements and the fins 15 and are made of a material having a high thermal conductivity like the fins 15. When the heat conducting members 16 and 17 come into contact with the heat generating elements, the heat of the heat generating elements is efficiently transmitted to the fins 15.

  The fixing unit 4 fixes the blower unit 2 and the heat radiating unit 3 to a predetermined member, for example, a substrate on which a heating element such as a CPU is mounted. The fixed unit 4 according to the present embodiment has four leg portions 19.

  1 and 2, the alternate long and short dash line X indicates the position of the rotating shaft 12 of the blower unit 2 (hereinafter referred to as the rotational axis position X), and the alternate long and short dash line Y indicates the laminated region of the fins 15 of the heat dissipation unit 3. The position of a line passing through the center of (cooling region) and parallel to the flow direction of the cooling air is shown (hereinafter referred to as cooling region center position Y). In the heat sink 1 according to the present embodiment, the rotation axis position X and the cooling region center position Y do not coincide with each other, and there is a shift of the distance L between them. In the present embodiment, the rotation axis position X is shifted to the left with respect to the cooling region center position Y (relative to the traveling direction of the cooling air). 2, the outer edge portion 21 of the fan 11 of the blower unit 2 is exposed to the outside from the outer edge portion 22 of the fin 15 of the heat radiating unit 3.

  Due to the positional relationship between the air blowing unit 2 and the heat radiating unit 3 as described above, the cooling air discharged from the air blowing unit 2 is the internal cooling air A1 that circulates inside the fin 15 of the heat radiating unit 3 and the outer edge portion of the fin 15. The air is diverted to the external cooling air A <b> 2 that circulates outside of 22.

  FIG. 3 shows the internal structure of a computer (electronic device) 30 on which the heat sink 1 is mounted. The computer 30 includes a casing 31, a motherboard 32, a graphic board 33, an exhaust unit 34, a power supply unit 35, a drive bay 36, a connector 37, the heat sink 1, and the like.

  The mother board 32 is fixed in the casing 31 in parallel with the side surface of the casing 31 (perpendicular to the ground). A main CPU 41, which is a heat generating element, a heat sink 1, a memory 42, a graphic board 33, and the like are fixed to the motherboard 32. The main CPU 41 is a main cooling target of the heat sink 1. The heat sink 1 is disposed so as to cover the main CPU 41, and is fixed to the mother board 32 by the legs 19. At this time, the heat conducting members 16 and 17 come into contact with the main CPU 41.

  The graphic board 33 is fixed perpendicularly to the motherboard 32 (parallel to the ground). The graphic board 33 is equipped with a CPU 45 that is a heat generating element. The CPU 45 is located on the side of the heat sink 1 through which the external cooling air A2 flows.

  The exhaust unit 34 is for exhausting the air inside the casing 32 to the outside. The present invention does not require a limitation on the configuration of the exhaust unit 34. For example, a general exhaust unit 34 including a fan, an electric motor, a control circuit, and the like can be used. In the present embodiment, the exhaust unit 34 is disposed at a position where the internal cooling air A1 and the external cooling air A2 discharged from the heat sink 1 are efficiently discharged.

  With the above configuration, the external cooling air A <b> 2 circulates in the vicinity of the CPU 45 that is a heat generating element of the graphic board 33. As a result, air in the vicinity of the CPU 45 is prevented from stagnation and a good cooling effect is obtained.

  As described above, by using the heat sink 1 according to the present embodiment, it is possible to eliminate local stagnation of air inside the computer 30 without requiring additional or increased blowing mechanisms.

  The present invention is not limited to the above-described embodiment, and can be appropriately changed without departing from the spirit of the present invention.

  For example, although FIG.1 and FIG.2 was shown as a concrete form of a heat sink, the component of this invention should not be interpreted limitedly to forms, such as the ventilation unit 2, the thermal radiation unit 3, etc. of the figure. The present invention can be applied to any form of blower that generates cooling air and any form of heat radiation member (unit) having a heat radiation effect.

  In the above embodiment, only the rotation axis position X and the cooling region center position Y are shifted as a method for generating the external cooling air A2, but the present invention is not limited to this method. Absent. For example, it is conceivable to make the diameter of the fan 12 larger than the outer diameter of the heat dissipation unit 3.

  Furthermore, although the tower-type computer 30 has been illustrated as an example of the electronic device using the heat sink, it is obvious that the heat sink according to the present invention can be used for various other electronic devices. The heat sink according to the present invention can be used in various devices that employ a forced convection type cooling mechanism.

1 Heat sink 2 Blower unit (blower)
3 Heat dissipation unit (heat dissipation member)
4 fixed unit 11 (multi-blade) fan 12 rotating shaft 13 fan guard 15 fin 16 heat conduction plate 17 heat conduction bridge 19 leg 30 computer (electronic equipment)
31 Casing 32 Motherboard 33 Graphic Board 34 Exhaust Unit 35 Power Supply Unit 36 Drive Bay 37 Connector 41 Main CPU
42 memory 45 CPU
A1 Internal cooling air A2 External cooling air X Rotating shaft position Y Cooling area center position

Claims (8)

A heat dissipating member for promoting heat dissipation of the heating element;
A blower for generating cooling air flowing through the heat dissipating member;
With
The blower is configured such that the cooling air circulates not only inside the outer edge of the heat dissipation member but also outside the outer edge.
heatsink. The blower has a fan member and a rotating shaft that rotates the fan member,
The rotating shaft is offset from the center of the cooling region inside the outer edge of the heat dissipation member;
The heat sink according to claim 1. The flow direction of the cooling air is parallel to the surface to which the heat generating member is fixed.
The heat sink according to claim 1 or 2.   The electronic device which has at least one said heat generating element and the heat sink as described in any one of Claims 1-3. A first heating element and a second heating element;
The first heating element is directly cooled by the heat dissipation member of the heat sink,
The second heat generating element is disposed on a side through which cooling air flowing outside the outer edge of the heat sink flows.
The electronic device according to claim 4. The first heating element is an element fixed to the first substrate;
The second heat generating element is an element fixed to a second substrate erected on the first substrate.
The electronic device according to claim 5. The first substrate is a motherboard;
The electronic device according to claim 6. The second substrate is a graphic board;
The electronic device according to claim 7.

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