JP2010080564A - Liquid cooling system - Google Patents

Abstract

A plurality of heat generation sources having different heat generation amounts per unit time; a flow path plate having a heat reception flow path in thermal contact with the plurality of heat generation sources; at least one connected to the heat reception flow path In a liquid cooling system comprising a radiator; and a pump that circulates a refrigerant between the heat receiving flow path and the radiator; without relying on a complicated flow path lengthening and / or an increase in pump load capacity, in particular A liquid cooling system capable of efficiently cooling the maximum heat generation heat source is obtained.
A heat receiving flow path of a flow path plate with respect to a specific radiator as a reference, a front heat receiving flow path positioned in front of the radiator in a fluid flow direction, and a rear heat receiving flow positioned in the fluid flow direction rearward of the radiator A liquid cooling system that is divided into a path and the maximum heat generation heat source is brought into thermal contact with both the front heat receiving channel and the rear heat receiving channel.
[Selection] Figure 1

Description

  The present invention relates to a liquid cooling system for cooling a heating element (in particular, a heat generation source of a PC).

Recent notebook personal computers have not only a CPU but also a plurality of heating elements such as GPUs and chip sets, and how to effectively cool the plurality of heating elements is a technical problem. Notebook PCs with limited storage space for parts require a liquid cooling system that is thin overall and highly unity.
Japanese Patent Laid-Open No. 5-283571 JP 2003-75037 A JP 2005-222443 A JP 2005-228216 JP JP 2007-103702 JP 2007-272294 A

  Theoretically, in such a liquid cooling system, when the flow rate of the refrigerant (coolant) is constant, the cooling capacity is improved by taking a long heat receiving channel for receiving heat from the heat source and a heat releasing channel for radiating heat. Although it can be increased, in a small device such as a notebook PC, it is difficult to take a long flow path, a large pressure loss occurs, and a load on the pump increases.

  The present invention can efficiently cool, in particular, a heat source having the largest amount of heat generation among a plurality of heat sources without relying on a complicated flow path and / or increased load capacity of the pump. The purpose is to obtain a liquid cooling system.

  The present invention pays attention to a heat source having the largest heat generation amount among a plurality of heat generation sources, and the maximum heat generation heat source is received by the flow path before entering the radiator and the flow path after exiting the radiator. For example, it was made based on the viewpoint that efficient heat reception (cooling) can be performed.

  That is, the present invention provides a plurality of heat generation sources having different heat generation amounts per unit time; a flow path plate having a heat reception flow path that is in thermal contact with the plurality of heat generation sources; and connected to the heat reception flow path. In a liquid cooling system comprising at least one radiator; and a pump for circulating a refrigerant between the heat receiving flow path and the radiator, the heat receiving flow path is located forward of the radiator in the fluid flow direction with respect to the specific radiator. The heat receiving channel is divided into a front heat receiving channel positioned behind and a rear heat receiving channel positioned rearward in the fluid flow direction from the radiator, and the heat generating source having the largest heat generation amount among the plurality of heat generating sources is separated from the front heat receiving channel and the rear receiving channel. It is characterized by being in thermal contact with both of the heat flow paths.

  The amount of heat received from the maximum heat generation heat source of the front heat receiving channel and the rear heat receiving channel is practically different from each other in consideration of the amount of heat received from other heat sources.

  Of the plurality of heat sources, heat sources other than the maximum heat generation amount heat source can be brought into thermal contact with only one of the front heat receiving channel and the rear heat receiving channel.

  More specifically, when there are three heat sources, two heat sources other than the maximum heat generation heat source can be brought into thermal contact with the front heat receiving channel and the rear heat receiving channel, respectively.

  In the liquid cooling system of the present invention, it is preferable to provide a cooling fan for supplying cooling air to the radiator.

  For example, the heat source is a CPU, a GPU, and a chip set.

  In order to enable mounting on a small device such as a notebook PC, the pump can be a piezoelectric pump.

  In another aspect, the subject of the present invention covers electrical equipment (PC, video equipment, imaging equipment, lighting device, etc.) equipped with the above liquid cooling system.

  In the liquid cooling system of the present invention, the heat receiving flow path of the flow path plate is positioned with respect to a specific radiator as a front heat receiving flow path positioned in front of the radiator in the fluid flow direction, and positioned rearward in the fluid flow direction from the radiator. The heat generation source having the largest heat generation amount among the plurality of heat generation sources is brought into thermal contact with both the front heat reception flow channel and the rear heat reception flow channel. It can be cooled efficiently.

  1 to 5 show an embodiment of a liquid cooling system according to the present invention. In this embodiment, three heat generation sources CPU 21, GPU 22 and chip set 23 are placed on a single flow path plate (planar flow path plate) 10, and these CPU 21, GPU 22 and This is an embodiment in which a heat receiving flow path of a refrigerant (coolant) flowing in the lower part (or upper part) of the chip set 23 is formed. The calorific values per unit time of the CPU 21, GPU 22 and chipset 23 are, for example, 15W, 30W and 5W, and the GPU 22 is the maximum calorific value heat source. A heat spreader 21S, a heat spreader 22S, and a heat spreader 23S that transfer the heat of these heat sources to the flow path plate 10 are interposed between the CPU 21, the GPU 22, the chip set 23, and the flow path plate 10, respectively.

  The flow path plate 10 has a flat flow path 11. FIG. 3 shows an example of the structure of the flow path plate 10 composed of three laminated metal plates (for example, brazing sheets) 10a, 10b, 10c. The middle laminated plate 10b is closed by the front and back laminated plates 10a and 10c. A through hole 11t constituting the planar flow path 11 is formed. The flow path plate 10 can also be composed of two or four or more metal plates.

  The flow path plate 10 is divided into a heat receiving area having the CPU 21, the GPU 22 and the chip set 23 in the substantially right half of FIG. 1 and a heat dissipation drive area in the substantially left half, and the heat dissipation drive area includes the first radiator 31. A second radiator 32, a cooling fan (sirocco fan) 33, and a piezoelectric pump 40 are mounted. The first radiator 31 and the second radiator 32 are arranged at the corners of the flow path plate 10 in a positional relationship orthogonal to each other, and the cooling fan 33 is connected to the first radiator 31 and the second radiator 32. It arrange | positions in the enclosed space and gives a cooling wind to the 1st radiator 31 and the 2nd radiator 32. FIG. The passage plate 10 is formed with a through hole 12 (FIG. 1) through which cooling air from the cooling fan 33 passes. Although the first radiator 31 and the second radiator 32 are divided in the present embodiment, they may be integrally formed.

  The planar flow path 11 of the flow path plate 10 exits from the discharge port 41 of the piezoelectric pump 40 and flows above the chip set 23 and above the GPU 22, and then is folded back on the lower surface of the GPU 22, and again above the GPU 22 and the chip set 23. And enter the first radiator 31 and the second radiator 32. The flow path that enters the first radiator 31 from the discharge port 41 of the piezoelectric pump 40 is the front heat receiving flow path 11F that is positioned forward in the flow direction of the first radiator 31 and the second radiator 32, and this front heat receiving flow path. While the refrigerant flows through 11F, the heat of the chip set 23 and the heat of a part of the GPU 22 (approximately 1/3) are received.

  Each of the first radiator 31 and the second radiator 32 has outer flow paths 31a and 32a and inner flow paths 31b and 32b branched into a plurality of stages, and the front heat receiving flow path 11F includes the outer flow path 31a, After being cooled by flowing through 32a, after flowing over the CPU 21 and above the GPU 22, folded back above the GPU 22, and again flowing above the GPU 22 and above the CPU 21, the inner flow path 32b of the second radiator 32 is returned. And flows through the inner flow path 31 b of the first radiator 31 and returns to the suction port 42 of the piezoelectric pump 40. The flow path from the outer flow path 32a to the inner flow path 32b of the second radiator 32 is a rear heat receiving flow path 11R located at the rear of the first radiator 31 and the second radiator 32 in the flow direction. While the refrigerant flows through the heat flow path 11R, the heat of the CPU 21 and the heat of a part (generally 2/3) of the GPU 22 are received. In this embodiment, the front heat receiving flow path 11F and the rear heat receiving flow path 11R are arranged forward and rearward with the outer flow path 31a of the first radiator 31 or the outer flow path 32a of the second radiator 32 as a specific radiator. It is the heat receiving flow path located.

  In FIG. 1, for convenience of illustration, the front heat receiving flow path 11 </ b> F and the rear heat receiving flow path 11 </ b> R (and the flow path connecting the first and second radiators 31 and 32) are drawn with solid lines, and the flow paths 31 a in the radiators 31 and 32 are drawn. , 31b, 32a, 32b are drawn by broken lines.

  As described above, the planar flow path 11 of the flow path plate 10 is divided into the front heat receiving flow path 11F and the rear heat receiving flow path 11R that flow before and after the first radiator 31 and the second radiator 32. Since the heat flow path 11F and the rear heat receiving flow path 11R take away the heat of the GPU 22 which is the maximum heat generation amount heat source, the GPU 22 can be efficiently cooled. That is, since the refrigerant flowing through the front heat receiving flow path 11F is cooled when passing through the inner flow path 32b of the second radiator 32 and the inner flow path 31b of the first radiator 31, The part can be cooled. Then, the refrigerant whose temperature has been raised as a result is cooled when passing through the outer flow path 31a of the first radiator 31 and the outer flow path 32a of the second radiator 32, and then flows through the rear heat receiving flow path 11R, and the CPU 21 Since the remaining part of the GPU 22 can be cooled, the GPU 22 which is the maximum heat generation heat source can be efficiently cooled.

  Although this embodiment does not ask about the specific structure of the piezoelectric pump 40, the structure of the piezoelectric pump 40 shown in FIG. 4 is demonstrated. FIG. 4 is drawn with the vertical relationship reversed from FIG. The piezoelectric pump 40 has a split housing 40L and an upper housing 40U that make a pair. In the divided housing 40L, a discharge port 41 and a suction port 42 are bored in parallel to each other so as to be orthogonal to the plate thickness plane of the housing. A piezoelectric vibrator (diaphragm) 44 is sandwiched and supported between the divided housing 40L and the upper housing 40U via an O-ring 43, and a pump is interposed between the piezoelectric vibrator 44 and the divided housing 40L. Chamber P is configured. An atmospheric chamber A is formed between the piezoelectric vibrator 44 and the upper housing 40U.

The piezoelectric vibrator 44 is a unimorph type having a central shim 44a and a piezoelectric body 44b formed on one surface of the front and back of the shim 44a (upper surface in FIG. 4). A shim 44a faces the pump chamber P and comes into contact with the refrigerant. The shim 44a is made of a conductive metal thin plate material, for example, a spring metal material (conductive metal thin plate) such as stainless steel or 42 alloy having a thickness of about 30 to 300 μm. The piezoelectric body 44b is made of a piezoelectric material such as PZT (Pb (Zr, Ti) O ₃ ) having a thickness of about 50 to 600 μm, for example, and is polarized in the front and back directions. Such a piezoelectric vibrator is well known.

  The discharge port 41 and the suction port 42 of the divided housing 40L are provided with check valves (umbrellas) 45 and 46, respectively. The check valve 45 is a discharge-side check valve that allows a fluid flow from the pump chamber P to the discharge port 41 and does not allow the reverse fluid flow. The check valve 46 passes from the suction port 42 to the pump chamber P. This is a suction-side check valve that permits the fluid flow of the fluid and does not permit the reverse fluid flow.

  The check valves 45 and 46 have the same form, and are provided with umbrellas 45b and 46b made of an elastic material on perforated substrates 45a and 46a that are bonded and fixed to the flow path. Such a check valve (umbrella) itself is well known.

  In the piezoelectric pump 40 described above, when the piezoelectric vibrator 44 is elastically deformed (vibrated) in the forward and reverse directions, the suction-side check valve 46 is opened and the discharge-side check valve 45 is closed in the stroke in which the volume of the pump chamber P is increased. Therefore, the refrigerant flows into the pump chamber P from the suction port 42. On the other hand, in the process of reducing the volume of the pump chamber P, the discharge side check valve 45 is opened and the suction side check valve 46 is closed, so that the refrigerant flows out from the pump chamber P to the discharge port 41. Therefore, the pump action can be obtained by elastically deforming (vibrating) the piezoelectric vibrator 44 continuously in the forward and reverse directions.

  The 1st radiator 31 and the 2nd radiator 32 should just be what can cool the refrigerant | coolant which passes, and may be united. Further, the outer flow paths 31a and 32a and the inner flow paths 31b and 32b of the first and second radiators 31 and 32 are functionally independent radiators, and thus are configured as separate radiators. May be. The first radiator 31 and the second radiator 32 in the illustrated embodiment have substantially the same structure, and FIG. 5 shows an example of the structure. The radiator 31 (32) is formed by laminating a plurality of laminated flow path plates 33 (four stages in the illustrated example). A spacer 34 for ensuring a space (air flow gap) between the laminated flow path plates 33 is inserted between the four stages of the flow path plates 33. Each laminated flow path plate 33 includes three laminated plates (brazing sheets) 33a, 33b, and 33c. A through hole 33d that forms the outer flow path 31a (32a) and the inner flow path 31b (32b) is formed in the middle laminated plate 33b, and both end portions of all the through holes 33d are connected via the communication path 35. And communicated with the flat channel 11. Although not shown, a refrigerant reserve tank can be provided as appropriate in communication with the planar flow path 11.

  FIG. 6 shows a planar flow path example of the flow path plate of the liquid cooling system of the comparative example. In this comparative example, only the front heat receiving flow path 11 </ b> R that exits the discharge port 41 of the piezoelectric pump 40 and enters the first and second radiators 31 and 32, in the order of the CPU 21, the GPU 22, and the chip set 23, Has passed.

  7 shows that when the heat generation amount per unit time of the CPU 21, GPU 22 and chip set 23 is 15 W, 30 W and 5 W, respectively, and the discharge amount of the piezoelectric pump 40 is 30 ml / min, FIG. It is the graph which investigated the cooling performance in a liquid cooling system and the comparative example of FIG. The solid line in FIG. 7 shows the planar flow path 11 (front heat receiving flow path 11F and rear heat receiving flow path 11R from the discharge port 41 of the piezoelectric pump 40 to the outlet of the inner flow path 31b of the first radiator 32 in the liquid cooling system of FIG. ) In which the liquid temperature of the refrigerant (and the junction temperature (j temperature) of each heat generation source) is plotted, and the maximum temperature in the GPU 22 of the maximum heat generation heat source is suppressed to about 65 ° C. In FIG. 7, for convenience, the first radiator 31 and the second radiator 32 are regarded as one radiator, and in FIG. 7, the Rad1 in liquid temperature is the liquid at the inlet of the outer flow path 31 a of the first radiator 31. The Rad1 out liquid temperature indicates the liquid temperature at the outlet of the outer flow path 32a of the second radiator 32. Similarly, in FIG. 7, the Rad2 in liquid temperature indicates the liquid temperature at the inlet of the inner flow path 32 b of the second radiator 32, and the Rad2 out liquid temperature indicates the liquid temperature at the outlet of the inner flow path 31 b of the first radiator 31. Is shown.

  On the other hand, the broken line in FIG. 7 is a plot of the comparative example in FIG. 6, and the maximum temperature of the maximum heat generation amount heat source GPU 22 reaches about 80 ° C. That is, as in the present embodiment, the planar flow path 11 of the flow path plate 10 is divided into a front heat receiving flow path 11F and a rear heat receiving flow path 11R that flow before and after the first radiator 31 and the second radiator 32, When the GPU 22 that is the maximum heat generation amount heat source is cooled by the front heat receiving channel 11F and the rear heat receiving channel 11R, the GPU 22 can be efficiently cooled.

  In the above embodiment, the radiator is divided into the first and second radiators 31 and 32. However, the number may be one or three or more. In the above embodiment, the heat sources are the CPU 21, the GPU 22, and the chip set 23, and among them, the heat generation amount of the GPU 22 is the maximum. However, the present invention provides a plurality of heat sources having different heat generation amounts. The cooling system can be used in general.

It is a top view which shows one Embodiment of the liquid cooling system by this invention. It is a front view of FIG. It is sectional drawing which shows the flow-path structure of the flow-path board of FIG. It is sectional drawing which follows the IV-IV line of FIG. It is sectional drawing which follows the VV line of FIG. It is a flow path figure corresponding to Drawing 1 showing the liquid cooling system of a comparative example. It is a graph which shows the specific example of the cooling performance of the liquid cooling system by this invention.

Explanation of symbols

DESCRIPTION OF SYMBOLS 10 Flow path board 10a 10b 10c Laminate board 11 Plane flow path 11F Front heat receiving flow path 11R Back heat receiving flow path 11t Through-hole 21 CPU (Heat generation source)
22 GPU (Maximum calorific value heat source)
23 Chipset (heat source)
21S 22S 23S Heat spreader 31 First radiator 32 Second radiator 31a 32a Outer channel 31b 32b Inner channel 33 Cooling fan 40 Piezoelectric pump 41 Discharge port 42 Suction port 44 Piezoelectric vibrator 45 Suction side check valve 46 Discharge side reverse valve Stop valve

Claims (8)

Multiple heat sources with different amounts of heat generation per unit time;
A channel plate having a heat receiving channel in thermal contact with the plurality of heat sources;
At least one radiator connected to the heat receiving flow path; and a pump for circulating a refrigerant between the heat receiving flow path and the radiator;
In a liquid cooling system with
The heat receiving flow path is divided into a front heat receiving flow path positioned forward of the radiator in the fluid flow direction and a rear heat receiving flow path positioned rearward of the radiator in the fluid flow direction with respect to a specific radiator,
A liquid cooling system characterized in that a heat generating source having the largest heat generation amount among the plurality of heat generating sources is brought into thermal contact with both the front heat receiving channel and the rear heat receiving channel. 2. The liquid cooling system according to claim 1, wherein the amount of heat received from the heat generating source having the largest amount of heat generated in the front heat receiving channel and the rear heat receiving channel is different from each other. 3. The liquid cooling system according to claim 1, wherein a heat generation source other than the heat generation source having the largest heat generation amount among the plurality of heat generation sources is in thermal contact with only one of the front heat reception flow path and the rear heat reception flow path. Liquid cooling system. 4. The liquid cooling system according to claim 3, wherein there are three heat sources, and the two heat sources other than the heat source having the largest calorific value are in thermal contact with the front heat receiving channel and the rear heat receiving channel, respectively. Cold system. 5. The liquid cooling system according to claim 1, further comprising a cooling fan that supplies cooling air to the radiator. 6. The liquid cooling system according to claim 1, wherein the heat generation source includes a CPU, a GPU, and a chip set. 7. The liquid cooling system according to claim 1, wherein the pump is a piezoelectric pump. An electric device equipped with the liquid cooling system according to any one of claims 1 to 7.

Images