JP2008225731A - Liquid cooling system - Google Patents

Abstract

[PROBLEMS] To provide a liquid cooling system capable of efficiently radiating heat when there are a plurality of heating elements, and has excellent unit properties that do not require a tube body as a whole, facilitating thermal coupling of each heating element plane, Provided is a liquid cooling system having good shape following to each heating element.
A heat dissipating sheet having a pair of heat conductive metal plates 10U, 10L superposed and having a circulation channel between the pair of heat conductive metal plates, a plurality of heat receiving areas partitioned on the heat dissipating sheet 10, A plurality of heating elements installed on each heat receiving area via heat spreaders 101H, 102H, and 103H made of a heat transfer material, inlet holes 12 positioned at both ends of the circulation channel, opened on the surface of the heat dissipation sheet, and Liquid cooling having an outlet hole 13, a discharge port and a suction port communicating with the inlet hole and the outlet hole, and a radiator 20 continuous with the circulation path of the pump 20 and the heat radiating sheet 10 installed on the heat radiating sheet 10 system.
[Selection] Figure 1

Description

  The present invention relates to a thin liquid cooling (water cooling) system, and more particularly to a liquid cooling system suitable for use in a notebook personal computer having a plurality of heating elements (heating sources).

Recent notebook personal computers have not only a CPU but also a plurality of heating elements such as a GPU and a chip set, and how to effectively cool the plurality of heating elements is a technical problem. In notebook computers with limited storage space for components, a liquid cooling system that is thin overall and highly unity is required.
JP 2005-166030 A JP 2004-211932 A JP 2003-324174 A JP 2003-124670 A JP 2002-94277 A Japanese Patent Laid-Open No. 2002-94276 Japanese Patent Application No. 2006-285842

  However, the conventional product is equipped with a pump, a heat absorption part, a heat radiation part (radiator), etc. separately, and requires a tube to connect each element. The amount of evaporation of the liquid was large, and there was a problem in assemblability. Further, in a notebook personal computer having a plurality of heating elements, a heat dissipation structure that can dissipate heat more efficiently is desired.

  Accordingly, an object of the present invention is to obtain a liquid cooling system having a high unit property capable of efficiently radiating heat when a plurality of heating elements are present. Another object of the present invention is to provide a liquid cooling system that is excellent in unit properties that do not require a tube body as a whole system and that can suppress the evaporation amount of the cooling liquid.

  The liquid cooling system according to the present invention has a pair of heat conductive metal plates stacked, and a heat dissipation sheet having a circulation channel between the pair of heat conductive metal plates; a plurality of heat receiving areas partitioned on the heat dissipation sheet; A plurality of heating elements installed on each heat receiving area via heat spreaders made of a heat transfer material; inlet holes and outlet holes located at both ends of the circulation flow path opened on the surface of the heat radiating sheet; It has a discharge port and a suction port communicating with the hole and the outlet hole, and has a pump installed on the heat radiation sheet; and a radiator continuous with the circulation flow path of the heat radiation sheet.

  It is preferable to set the plurality of heat receiving areas through an easily deformable portion formed on the heat dissipation sheet. In one embodiment, the easily deformable portion can be a slit formed in at least one of a pair of heat conductive metal plates constituting the heat radiating sheet.

  In one mode, the heat dissipation sheet and the radiator can be formed in a plane U shape, and a fan that supplies cooling air to the radiator can be disposed in the U shape space.

  The heat sink and the heating element can be positioned on one surface of the heat dissipation sheet, and the pump can be positioned on the other surface.

  The inlet and outlet holes of the circulation channel are formed as cylindrical projections on the heat dissipation sheet, and the discharge port and suction port of the pump are connected to the discharge channel holes and outlet hole cylindrical projections communicating with the inlet hole cylindrical projection. It is good to form as a suction port hole which communicates.

  If the pump is a piezoelectric pump, a thin liquid cooling system can be obtained.

  The liquid cooling system of the present invention is useful when the heating element includes the CPU and GPU of a notebook computer.

  In one aspect, the radiator has a plurality of stacked flow path units, and each flow path unit includes an inlet hole and an outlet hole, and a cooling flow path connecting the inlet hole and the outlet hole.

  More specifically, each flow path unit is configured by laminating and combining a pair of flow path plates that form a liquid flow path bent at least once in a U shape, for example, An inlet hole and an outlet hole are formed.

  More specifically, the pair of flow path plates constituting each flow path unit has a plane symmetrical shape that is symmetric with respect to the overlapping surface, a flow path recess having a plane U shape, and one end of the flow path recess. The inlet hole and the outlet hole formed at the other end may be formed.

  In the liquid cooling system of the present invention, a plurality of heating elements are installed through a heat spreader in a plurality of heat receiving areas partitioned on the radiation sheet, a pump is installed on the radiation sheet, and a radiator is connected. Therefore, it has high unit property, and a plurality of heating elements can be efficiently cooled by one pump and a radiator. Moreover, the evaporation amount of the cooling liquid can be suppressed, and a cooling system excellent in maintainability can be provided.

  As shown in FIGS. 1 to 3, the liquid cooling system unit 100 according to the present embodiment includes a heat radiating sheet 10, a piezoelectric pump 20, a radiator 40, and a cooling fan (sirocco fan) 50 as main components, and includes a CPU 101, a GPU 102, The three heat sources of the chip set 103 are cooled.

  The heat-dissipating sheet 10 is composed of a pair of superposed heat conductive metal plates 10U and 10L. On the sheet 10, through a counter slit (deformable part) 10a (by) three planar rectangular heat receiving areas A , B, and C are set. On the surface opposite to the upper heat transfer substrate 10U of the lower heat transfer metal plate 10L, the CPU 101, the GPU 102, and the chip set 103 are placed on the heat receiving areas A, B, and C through the heat spreaders 101H, 102H, and 103H, respectively. Is mounted (contacted).

  Each of the heat conductive metal plates 10U and 10L of the heat radiating sheet 10 is made of a metal material mainly composed of SUS, copper or aluminum, and the lower heat conductive metal plate 10U has a flow path constituting the circulation flow path 11. A recess 11a is formed. The depth of the channel recess 11a is, for example, about 0.5 mm.

  A channel blocking projection 11b is formed in the channel recess 11a (circulation channel 11), and the front and rear of the channel blocking projection 11b constitute a channel start end 11c and a channel end 11d. . The flow path start end 11c communicates with the heat absorption areas C, B, and A in the order of the heat absorption forward flow path 11e, the heat absorption return flow path 11f, and the heat absorption areas A, B, and C, and the heat absorption return flow path 11g. After reaching the inflow end 11h, the discharge end 11i from the radiator 40 continues to the flow path end 11d. Although the flow path is illustrated in a simplified manner, the flow path can be appropriately meandered to increase the flow path length.

  An inlet protrusion (inlet hole) 12 and an outlet protrusion (outlet hole) 13 communicating with the circulation flow path 11 are formed on the heat conductive metal plate 10U so as to correspond to the flow path start end 11c and the flow path end 11d. An outlet protrusion (outlet hole) 14 and an inlet protrusion (inlet hole) 15 are formed corresponding to the radiator inflow end 11h and the radiator discharge end 11i. The inlet protrusion 12 and the outlet protrusion 13 communicate (fit) with a discharge port (hole) 34 and a suction port (hole) 35 of the piezoelectric pump 20, respectively.

  The piezoelectric pump 20 is installed on the upper heat conductive substrate 10U of the heat radiating sheet 10. That is, the piezoelectric pump 20 is located on one surface of the heat dissipation sheet 10, and the CPU 101, GPU 102, and chip set 103 are located on the other surface. According to this arrangement, planar overlap with the cooling fan is allowed, cooling efficiency is improved, and the planar size of the entire liquid cooling system unit 100 can be suppressed. Further, if the piezoelectric pump 20 and the radiator 40 are arranged on the lower side in FIG. 1, the pump can be configured on the same surface as the heat source, so that the upper surface of the liquid cooling system unit 100 can be made flat. Therefore, the liquid cooling system unit 100 can be efficiently arranged.

  Although this invention does not ask | require the structure of pump (piezoelectric pump) 20 itself, the piezoelectric pump 20 of embodiment is demonstrated about FIG.5 and FIG.6. The piezoelectric pump 20 has a lower housing 21 and an upper housing 22 in order from the bottom.

  The lower housing 21 is provided with the discharge port 34 and the suction port 35 in parallel to each other so as to be orthogonal to the plate thickness plane of the housing. A piezoelectric vibrator (diaphragm) 28 is sandwiched and supported between the lower housing 21 and the upper housing 22 via an O-ring 29, and a pump is interposed between the piezoelectric vibrator 28 and the lower housing 21. Chamber P is configured. An atmospheric chamber A is formed between the piezoelectric vibrator 28 and the upper housing 22.

The piezoelectric vibrator 28 is a unimorph type having a shim 28a at the center and a piezoelectric body 28b formed by laminating on the front and back surfaces of the shim 28a (upper surface in FIG. 6). A shim 28a faces the pump chamber P and comes into contact with the liquid. The shim 28a is made of a conductive metal thin plate material, for example, a metal thin plate formed of stainless steel having a thickness of about 50 to 300 μm, 42 alloy, or the like. The piezoelectric body 28b is made of, for example, PZT (Pb (Zr, Ti) O ₃ ) having a thickness of about 300 μm, and is polarized in the front and back directions. Such a piezoelectric vibrator is well known.

  The discharge port 34 and the suction port 35 of the lower housing 21 are provided with check valves (umbrellas) 32 and 33, respectively. The check valve 32 is a suction-side check valve that allows a fluid flow from the suction port 35 to the pump chamber P and does not allow the reverse fluid flow. The check valve 33 transfers from the pump chamber P to the discharge port 34. This is a discharge-side check valve that allows the fluid flow of the fluid but does not permit the reverse fluid flow.

  The check valves 32 and 33 have the same configuration, and are provided with umbrellas 32b and 33b made of an elastic material on perforated substrates 32a and 33a that are bonded and fixed to the flow path. Such a check valve (umbrella) itself is well known.

  In the piezoelectric pump 20 described above, when the piezoelectric vibrator 28 is elastically deformed (vibrated) in the forward and reverse directions, the suction-side check valve 32 is opened and the discharge-side check valve 33 is closed in the process of expanding the volume of the pump chamber P. Therefore, the liquid flows into the pump chamber P from the suction port 35 (the outlet protrusion 13 of the heat dissipation sheet 10). On the other hand, in the process of reducing the volume of the pump chamber P, the discharge-side check valve 33 is opened and the suction-side check valve 32 is closed, so that liquid is supplied from the pump chamber P to the discharge port 34 (the inlet protrusion 12 of the heat radiation sheet 10). Leaks. Therefore, the pump action is obtained by causing the piezoelectric vibrator 28 to be elastically deformed (vibrated) continuously in the forward and reverse directions, and the liquid is received from the flow path start end 11 c of the circulation flow path 11 of the heat dissipation sheet 10 to the heat receiving area A. , B, C endothermic forward flow path 11e, endothermic return flow path 11f, and endothermic return flow path 11g, and after absorbing heat, reach the radiator inflow end 11h and enter the radiator 40. The liquid that radiates heat by circulating through the radiator 40 is discharged to the radiator discharge end 11i and returns to the flow path end 11d.

  The radiator 40 is directly connected to the outlet protrusion (exit hole) 14 and the inlet protrusion (inlet hole) 15 of the heat radiating sheet 10 (without passing through the tube body). As shown in FIGS. 7 to 9, the radiator 40 of this embodiment includes a flow path unit 41 that is stacked in a plurality of stages. Each flow path unit 41 has the same structure except for the uppermost flow path unit 41.

  Each flow path unit 41 is constituted by a pair of flow path plates 42U and 42L that are coupled in an overlapping manner. The flow path plates 42U and 42L are made of, for example, a press-formed product of a metal material (brazing sheet) having excellent heat conductivity, and have a symmetrical shape (same single shape) with respect to the overlapping surface (laminated surface). Yes. FIG. 10 shows a single shape of the flow path plate 42U (42L). The flow path plate 42U (42L) has an elongated shape, and has a flat joint surface 45 at the periphery of the planar U-shaped flow path recess 46. Spacer portions 47S and 48S are formed at both ends of the U-shaped channel recess 46 (the end opposite to the U-shaped folded portion) so as to protrude outward from the U-shaped channel recess 46 portion. An inlet hole 47 and an outlet hole 48 are formed in the spacer portions 47S and 48S.

  The flow path plates 42U and 42L are overlapped with each other so that the flow path recess 36 faces outward, and the joint surfaces 45 are joined by brazing, for example. Then, a flat U-shaped coolant flow path 11X is formed by the U-shaped flow path recesses 46 protruding in the opposite directions of the upper and lower sides. In addition, the spacer portions 47S (48S) of the upper and lower flow path units 41 are in contact with each other so that the inlet holes 47 and the outlet holes 47 of the upper and lower flow path units 41 communicate with each other. A cooling air passage space S (FIG. 9) is formed between the superimposed flow path units 41. An inlet hole 47 (outlet hole 48) is not formed in the spacer portion 47S (48S) of the flow path plate 42U above the uppermost flow path unit 41.

  The outlet protrusion (exit hole) 14 and the inlet protrusion (inlet hole) 15 formed on the heat conductive metal plate 10U are fitted into the inlet hole 47 and the outlet hole 48 of the lowermost flow path unit 41, respectively, from the radiator inflow end 11h. A plurality of layers of radiator flow paths reaching the radiator discharge end 11i are formed.

  The heat dissipating sheet 10 and the radiator 40 have a generally U-shaped planar shape, and the cooling fan (sirocco fan) 50 is disposed in the U-shaped space. The cooling air blowing direction W (FIGS. 1 and 3) of the cooling fan (sirocco fan) 50 is directed toward the radiator 40, and the cooling air passes through the space S between the flow path units 41 to flow path units. The liquid flowing in 41 is cooled. According to such a planar arrangement, the wind generated from the cooling fan 50 can be efficiently applied to the cooling system unit 100, so that space saving can be achieved.

  In the liquid cooling system unit 100 having the above-described configuration, heat receiving areas A, B, and C are defined on a single heat radiation sheet 10 (made of a continuous metal material). ), GPU 102 (heat sink 102H) and chipset 103 (heat sink 103H) are mounted. Further, the piezoelectric pump 20 and the radiator 40 are coupled to the heat radiating sheet 10, and all circulation channels are formed without using a flexible tube body. Since the heat receiving areas A, B, and C are defined by facing slits (deformable portions) 10a, even if there is a step between the CPU 101 (heat sink 101H), GPU 102 (heat sink 102H), and chipset 103 (heat sink 103H). Each heat receiving area can be flexibly deformed and can follow the steps, thereby facilitating thermal coupling to each heating element plane.

  The liquid discharged from the discharge port 34 of the piezoelectric pump 20 enters the circulation flow path 11 (flow path start end 11c) from the inlet protrusion 12 of the heat conductive metal plate 10U, and the heat absorption flow path 11e in the heat receiving areas A, B, and C. , 11f, 11g, and after absorbing heat from the CPU 101, GPU 102, and chipset 103, reaches the outlet projection 14 of the heat dissipation sheet 10 at the radiator inflow end 11h. The liquid reaching the outlet projection 14 enters the cooling channel 11X from the inlet hole 47 of each channel unit 41 of the radiator 40, exits from the outlet hole 48, and is then discharged from the inlet projection 15 to the radiator discharge end 11i. Return to the road end 11d. The liquid that has reached the channel end 11d returns to the piezoelectric pump 20 from the inlet protrusion 12 and repeats the same circulation. The liquid passing through the cooling flow path 11X in the radiator 40 is sufficiently cooled by the cooling air from the cooling fan (sirocco fan) 50.

  In the above embodiment, the easily deformable part is formed in the heat dissipation sheet 10 by the opposing slit (deformable part) 10a, but the easily deformable part may be formed by a thin part. Further, in the illustrated example, the opposing slit (deformable part) 10a is formed in both of the heat conductive metal plates 10U and 10L, but the opposing slit (deformable part) 10a may be formed only in one.

It is a disassembled perspective view which shows one Embodiment of the liquid cooling system by this invention. It is a disassembled perspective view of the thermal radiation sheet | seat of FIG. It is the same top view. FIG. 4 is a side view of FIG. 3. It is a top view of a piezoelectric pump single-piece | unit. It is sectional drawing which follows the VI-VI line of FIG. It is a perspective view of a radiator simple substance. It is sectional drawing which follows the VIII-VIII line of FIG. 7 is a cross-sectional view taken along line IX-IX. It is a top view of the channel plate simple substance which comprises each channel unit of a radiator.

Explanation of symbols

100 Liquid cooling system unit 101 CPU
102 GPU
103 Chipset 101H 102H 103H Heat spreader 10 Heat radiation sheet 10a Opposing slit (deformable part)
10U 10L Heat transfer metal plate 11 Circulation flow path 11a Flow path recess 11b Flow path blocking projection 11c Flow path start end 11d Flow path end 11e 11f 11g Heat absorption flow path 11h Radiator inflow end 11i Radiator discharge end 11X Cooling flow path 12 Inlet protrusion ( Inlet hole)
13 Exit protrusion (exit hole)
14 Exit protrusion (exit hole)
15 Entrance protrusion (inlet hole)
20 Piezoelectric pump (pump)
21 Lower housing 22 Upper housing 28 Piezoelectric vibrator (diaphragm)
28a shim 28b piezoelectric body 29 O-ring 32 check valve 32a perforated substrate 32b umbrella 33 reverse support valve (umbrella)
33a Perforated base 33b Umbrella 34 Discharge port 35 Suction port P Pump chamber A Atmosphere chamber 40 Radiator 41 Channel unit 42L Channel plate 42U Channel plate 45 Joint surface 46 U-shaped channel recess 47 Inlet hole 47S 48S Spacer 48 Outlet hole 50 Cooling fan (sirocco fan)

Claims (11)

A heat-dissipating sheet having a pair of heat conductive metal plates superposed and having a circulation channel between the pair of heat conductive metal plates;
A plurality of heat receiving areas partitioned on the heat dissipation sheet;
A plurality of heating elements installed on each heat receiving area through heat spreaders made of heat transfer materials;
An inlet hole and an outlet hole located at both ends of the circulation channel, which are opened on the surface of the heat dissipation sheet;
A pump having a discharge port and a suction port communicating with the inlet hole and the outlet hole, and installed on the heat dissipation sheet;
And a radiator continuous to the circulation flow path of the heat dissipation sheet;
A liquid cooling system comprising: 2. The liquid cooling system according to claim 1, wherein the plurality of heat receiving areas are partitioned and set via an easily deformable portion formed in the heat dissipation sheet. The liquid cooling system according to claim 2, wherein the easily deformable portion is a slit formed in at least one of a pair of heat conductive metal plates constituting the heat radiating sheet. 4. The liquid cooling system according to claim 1, wherein the heat dissipating sheet and the radiator have a planar U shape, and a fan for supplying cooling air to the radiator is provided in the U shape space. Liquid cooling system in place. 5. The liquid cooling system according to claim 1, wherein the heat sink and the heating element are positioned on one surface of the heat dissipation sheet, and the pump is positioned on the other surface. 6. The liquid cooling system according to any one of claims 1 to 5, wherein the inlet hole and the outlet hole of the circulation flow path are formed as cylindrical protrusions on the heat radiating sheet, and the discharge port and the suction port of the pump are A liquid cooling system formed as a discharge port hole communicating with the inlet hole cylindrical protrusion and a suction port hole communicating with the outlet hole cylindrical protrusion. 7. The liquid cooling system according to claim 1, wherein the pump is a piezoelectric pump. The liquid cooling system according to claim 1, wherein the heating element includes a CPU and a GPU of a notebook computer. 9. The liquid cooling system according to claim 1, wherein the radiator includes a plurality of stacked flow path units, and each flow path unit includes an inlet hole and an outlet hole, and the inlet hole and the outlet. A liquid cooling system with a cooling channel that connects holes. 10. The liquid cooling system according to claim 9, wherein each flow path unit is formed by laminating a pair of flow path plates that form a liquid flow path bent at least once in a U shape, and the pair of flow path plates. And a liquid cooling system in which the inlet hole and the outlet hole are formed. The radiator according to claim 9 or 10, wherein the pair of flow path plates constituting each flow path unit has a plane symmetrical shape that is symmetrical with respect to the overlapping surface, and a flow path recess having a planar U shape, A liquid cooling system having the inlet hole and the outlet hole formed at one end and the other end of the channel recess.