JP2006216906A - Liquid-cooing system and electronic device having the same - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a liquid-cooling system capable of efficiently liquid-cooling a plurality of heat-generating elements in a chassis and an electronic device having the liquid-cooling system. <P>SOLUTION: A plurality of heat-receiving elements 3, fixed in close connection with a plurality of heat-generating elements 2, are connected to a heat-radiating unit 4 and a circulating pump 5 through pipes 6 and tubes 7. A piping system is constructed, such that at least one heat-receiving element 3 is connected in parallel to the other heat-receiving elements or elements 3, so that pipe resistance is reduced to allow the cooling medium, filled in the piping to fully circulate, even if a small circulating pump 5 is employed. <P>COPYRIGHT: (C)2006,JPO&NCIPI

Description

  The present invention relates to a technique for efficiently cooling a plurality of heat generating components provided in a device.

Conventionally, as for a cooling system that circulates a refrigerant by connecting a heat generating portion and a heat radiating portion in an annular shape with a tube, a technique for liquid cooling a heat generating body in a notebook personal computer disclosed in Patent Document 1 is known. Yes. This Patent Document 1 describes a coolant pump in which a coolant is circulated by connecting a ring between at least one heat generating portion including a CPU and a heat radiating portion in a ring shape. The suction side is connected to the heat radiation side of the tube through which the coolant circulates, and the discharge side of the coolant pump is connected to the heat receiving side of the tube through which the coolant circulates. Here, the heat generating part, the heat radiating part, and the coolant pump are connected in series by a tube.
JP 2003-263244 A (2nd page, FIG. 1)

However, when a liquid cooling system having only a serial circulation path disclosed in Patent Document 1 is applied to a device having a plurality of heat generating sections, a circulation path is formed so as to pass through all of the plurality of heat generating sections. Since the refrigerant passing through the heat generating part is warmed and the temperature rises, and the refrigerant inlet side in the heat generating part is the upstream side and the outlet side is the downstream side, the refrigerant temperature on the downstream side is high, There is a possibility that other heat generating parts arranged on the downstream side of the heat generating part may not be sufficiently cooled.
In other words, since the cooling measures are usually performed after the arrangement of the parts is determined from the design and electrical / mechanical aspects, the circulation path of the refrigerant to the heat-generating parts is restricted and the circulation path tends to be long. There is a disadvantage that the cooling efficiency becomes insufficient and the heat-strict heat generating component cannot be arranged downstream.
In addition, when there are multiple heat generating parts, connecting these heat generating parts and heat radiating parts in series will increase the pipe resistance, making it a large capacity pump to ensure the required flow rate, or increasing the pipe diameter. This was inconvenient for downsizing the housing.

  In view of this point, the present invention proposes a liquid cooling system capable of efficiently cooling a plurality of heating elements and an electronic device having the liquid cooling system.

  In order to solve the above-described problems, the present invention provides a liquid cooling system having a plurality of heat generating units, a heat receiving unit that absorbs heat from the heat generating unit, a refrigerant that takes heat away from the heat receiving unit by heat exchange, and heat from the refrigerant. The heat-dissipating part that dissipates heat by exchange, the heat-receiving part and the heat-dissipating part are connected, and the filled refrigerant is configured to be circulated, and at least one heat-receiving part among the plural heat-receiving parts provided These are connected by piping in parallel with other heat receiving parts.

  Further, the present invention is the liquid cooling system described above, wherein the refrigerant is circulated by a pump arranged in a pipe.

  Further, according to the present invention, in the liquid cooling system described above, a pipe is provided with a refrigerant flow rate adjusting mechanism.

  According to the liquid cooling system of the present invention configured as described above, since the refrigerant path is connected in parallel to the plurality of heat generating units, the heat generating unit can be efficiently cooled and the length of each of the plurality of paths is Therefore, unnecessary piping can be suppressed and pressure loss due to piping resistance can be reduced, and the circulation pump can be downsized.

  In order to solve the above problems, the present invention provides an electronic device having a liquid cooling system that cools a plurality of heat generating components, a heat receiving portion that absorbs heat from the heat generating portion, and a refrigerant that removes heat from the heat receiving portion through heat exchange. A heat dissipating part that dissipates heat by heat exchange from the refrigerant, and a pipe that connects the heat receiving part and the heat dissipating part and that allows the filled refrigerant to circulate freely. One heat receiving part is connected by piping in parallel with the other heat receiving part.

  In addition, the present invention is an electronic device having the liquid cooling system described above, wherein the refrigerant is circulated by a pump disposed in a pipe.

  Furthermore, the present invention is an electronic apparatus having the above-described liquid cooling system, wherein a pipe is provided with a refrigerant flow rate adjusting mechanism.

  According to the electronic apparatus having the liquid cooling system of the present invention configured as described above, since the refrigerant path is connected in parallel to the plurality of heat generating units, the heat generating unit can be efficiently cooled and each of the plurality of heat generating units can be cooled. Since the length of the path is suppressed and unnecessary piping can be suppressed, pressure loss due to piping resistance can be reduced, and a small circulation pump can be provided, and the housing can be made smaller. .

  According to the liquid cooling system of the present invention, the heat generating portion can be efficiently cooled, space can be saved, and the cost can be improved.

  According to the electronic apparatus having the liquid cooling system of the present invention, the housing can be reduced in size by saving the space of the components of the liquid cooling system, and the pump driving voltage can be suppressed because a small circulation pump is sufficient. Noise reduction and long-term reliability can be improved.

Hereinafter, an example of the best mode for carrying out the liquid cooling system and the electronic apparatus having the liquid cooling system of the present invention will be described with reference to FIGS.
FIG. 1 is a perspective view of a casing having the liquid cooling system of this example, and a plurality of heating elements provided in the casing are cooled by a circulating refrigerant. Here, examples of the refrigerant used in the liquid cooling system include pure water and water containing antifreeze.
In FIG. 1, reference numeral 1 denotes a casing, and two heating elements 2 to be cooled are provided in the casing 1. And in order to cool each of this heat generating body 2 and 2, a liquid cooling system is comprised by the two heat receiving parts 3 and 3 mounted in the housing | casing 1, the thermal radiation part 4, the pump 5, the pipe 6, and the tube 7. FIG. The

  As shown in FIG. 1 and FIG. 2, the heat receiving unit 3 is tightly fixed so as to be in thermal contact with the heating element 2, and reduces heat resistance in heat transfer from the heating element 2 to the heat receiving unit 3. Therefore, a heat transfer sheet or heat transfer grease (not shown) is interposed between the heating element 2 and the heat receiving portion 3. As shown in FIG. 2, the heat receiving section 3 has a space formed therein, and holes are provided at both ends so that the refrigerant 8 can flow, and pipes 6 and 6 described later are joined to the holes. The The heat receiving portion 3 is made of metal in order to effectively transfer the heat transferred from the heating element 2 to the refrigerant 8 so that the heat receiving surface of the heat receiving portion 3 can make sufficient contact with the heating element 2. It is formed.

As shown in FIG. 1, the heat dissipating unit 4 is for radiating heat from the refrigerant 8 which is transmitted from the heating element 2 via the heat receiving unit 3 and is warmed, and has good heat conductivity to increase the heat dissipating efficiency. It is desirable to make it from a metal, and a space is formed inside, and holes are provided at both ends so that the coolant 8 can flow. Here, as shown in FIG. 3, a plurality of walls 9 are provided in the space inside the heat radiating section 4 so that heat exchange with the inner wall of the heat radiating section 4 is facilitated as much as possible when the refrigerant 8 flows.
Further, in order to efficiently transmit heat from the heat radiating part 4 to the outside air, as shown in FIG. 1, an aluminum material is used to increase the surface area by attaching a plurality of fins to the outer surface of the heat radiating part 4 and to increase the heat radiation efficiency by radiation. It is desirable to use alumite treatment.
The heat dissipating section 4 can store a large volume of refrigerant, and also has a function of a reserve tank with respect to natural reduction of the refrigerant due to evaporation or the like.

The pipe 6 shown in FIG. 1 for connecting the heat receiving part 3, the heat radiating part 4, and the pump 5 is made of metal, and the tube 7 is made of resin having flexibility such as rubber. The flexible resin tube 7 is used when all metal pipes 6 are used. When the force of displacement is applied due to impact or vibration, local stress concentration occurs, leading to breakage and liquid leakage. This is because a resin tube having flexibility in place is used to buffer the force of misalignment so that stress is not concentrated.
Here, the pipe 6 is directly joined to the component as shown in FIG. 2 or connected to the component via a pipe joint. The tube 7 includes a pipe joint and a flexible resin tube connected to the pipe joint.

In the liquid cooling system of this example, as shown in FIG. 1, the two heat receiving portions 3, 3 are connected to each other in parallel by a pipe 6 and a tube 7. And when the refrigerant | coolant 8 with which the inside was filled is conveyed by the drive of the pump 5, the refrigerant | coolant 8 is shunted by the branch of piping downstream of the pump 5, receives heat from the heat generating body 2 through two heat receiving parts, Thereafter, the divided refrigerant 8 is integrated and supplied to the heat radiating section 4 to circulate.
That is, the refrigerant 8 is heated by the circulation of the refrigerant 8 in the order of the heat receiving part 3 → the refrigerant 8 → the heat radiating part 4 and the inner wall 9 → the outer wall fin of the heat radiating part 4 → the outside air. Then, the heat generating element 4 continues to be cooled by the circulating refrigerant 8 while the electronic device is being started and cooled.

Thus, in the liquid cooling system shown in FIG. 1, since the heat receiving parts 3 and 3 are connected in parallel to the pump 5, the two heating elements 2 and 2 are only cooled substantially in the same manner as compared with the case of series connection. In addition, since the piping resistance viewed from the pump 5 is substantially halved, it is not necessary to make the pump 5 large.
Since the flow rate is determined by the pipe line resistance and the capacity of the pump 5, the capacity and arrangement of the pump 5 and the specifications of the pipe 6 and the tube 7 are determined so that a necessary and sufficient flow rate can be secured.
The required flow rate required for each heat receiving unit for a plurality of heating elements is given by the following equation.
Required flow rate ≧ Total calorific value / (Refrigerant density x Refrigerant specific heat x Refrigerant temperature difference)
Here, ≧ is because there is a heat transfer loss between the heating element 2 and the refrigerant 8, and it is necessary to make the flow rate larger than the value estimated on the right side.

According to the cooling system of this example configured as described above, since the refrigerant 8 cooled by the heat radiating unit 4 is branched and flowed to each of the plurality of heat receiving units 3, the heating element 2 can be efficiently cooled. . In addition, since the length of each of the plurality of paths is suppressed and unnecessary piping can be suppressed, compared to the case where the plurality of heat receiving portions 3 are connected in series, in the parallel connection as in this example, the pressure loss due to the piping is reduced. Since the size is reduced and the load is reduced, a small pump 5 having a small capacity can be adopted, and the cooling system can be configured in a space-saving manner and can be made economical.
In addition, according to the electronic apparatus having the liquid cooling system of this example, not only can the housing be reduced in size by saving the space of the cooling system components, but also the circulating pump can be reduced in size so that the pump drive voltage is suppressed. This can reduce noise and improve long-term reliability.

In addition, when it has more heat generating bodies 2 than this with respect to the example of FIG. 1 having two heat generating elements 2, for example, as shown in FIG. 4, a plurality of heat receiving portions 3 may be connected in series. In this case, it is assumed that the heat generating element 2 disposed on the downstream side of the heat receiving unit 3 connected in series has a smaller amount of heat generation than the heat generating element 2 closely fixed to the heat receiving unit 3 disposed on the upstream side. . In general, when a plurality of heat receiving portions 3 are connected in series, the pipe resistance tends to increase and the flow rate tends to decrease. Therefore, the pipe diameter and the capacity of the circulation pump 5 are determined so that a necessary and sufficient refrigerant flow rate can be secured.
In addition, when a plurality of heating elements 2 are mounted in a narrow area due to the component layout, a plurality of heating elements 2 are closely fixed to one heat receiving portion 3 and cooled as shown in FIG. Good.

In addition, the piping system is not constituted by the pipe 6 or the tube 7, but as shown in FIGS. 6 and 7, the plate-like plate 10 made of a metal such as aluminum or magnesium or an alloy thereof that can be reduced in weight even if it is relatively thick. A circulation path 11 for the refrigerant 8 may be provided inside, and the heating element 2 may be fixed and fixed to a predetermined position of the plate 10 via a heat transfer sheet or the like.
In addition, as a structure of the plate 10, even if it is comprised by the single member shown in FIG. 6, it may be comprised by the several member shown in FIG. As shown in FIG. 7, in the plate 10 having a structure divided into a plurality of members, the flow path is shortened for each member unit, so that the production becomes easy.
Further, in order to increase the heat radiation amount as a whole, as shown in FIG. 8, heat radiation fins may be attached to the heat receiving portion 3 so that heat can be radiated from the heat receiving portion 3 itself.

Further, a plurality of pumps 5 may be used in order to secure a necessary flow rate in the heat receiving portions 3 and 3, for example, the arrangement of the pumps 5 is connected to each of the heat receiving portions 3 and 3 provided in parallel as shown in FIG. Or can be connected in series as shown in FIG.
When it is desired to accurately control the flow rate of each refrigerant 8 in the heat receiving unit 3, the pump 5 is connected to each heat receiving unit 3 shown in FIG. 9, and when the flow rate is simply increased, the refrigerant 8 is arranged in parallel as shown in FIG. The pumps 5 and 5 are connected in series to the heat receiving portions 3 and 3.

Further, in order to optimize the flow rate of the refrigerant 8 in each heat receiving unit 3, a flow rate control unit 13 may be provided in a pipe connected to each heat receiving unit 3 as shown in FIGS. 9 and 10.
As an example of the flow rate control unit 13, an orifice is provided in a part of the flow path with respect to the diameter of the pipe, or a pipe diameter is adjusted to be a desired flow rate by providing a smaller diameter part than the inner diameter of the pipe. A simple configuration may be used. The part shown in FIG. 11 is an example of the flow rate control unit 13 in which a small-diameter portion is provided in a pipe line, and screw holes for connecting pipe joints are provided on both sides of the part as shown in FIGS. 11A and 11B. A channel having a small diameter is formed in the substantially central portion.
Another example of the flow rate control unit 13 may include a detector that converts the flow rate of the refrigerant 8 into an electrical signal. In the flow rate control unit 13 having a detector, the pump drive voltage can be controlled so as to obtain a desired flow rate based on the detected electrical signal.

Further, in the example of FIG. 1, the heat radiating unit 4 is shown as being one surface in one housing, but the heat radiating portion 4 may be configured by a plurality of surfaces and attached to a single housing in a plurality.
Furthermore, in the above example, the tube 7 has been described as being made of a flexible resin. However, the present invention is not limited to this, and a flexible tube spirally or waved one by one to a metal such as a thin stainless steel pipe may be used. Although there is no particular mention of the joint, a bite joint, a face seal joint, or the like can be used.

  Of course, the liquid cooling system and the electronic device having the liquid cooling system of the present invention are not limited to the above-described examples, and can take various other configurations without departing from the gist of the present invention.

It is a schematic diagram which shows the example of embodiment of the electronic device which has this invention liquid cooling system and a liquid cooling system. It is a cross-sectional schematic diagram explaining the structure of the heat receiving part of the example of FIG. It is a cross-sectional schematic diagram explaining the structure of the thermal radiation part of the example of FIG. It is a schematic diagram which shows the example of the other form of the piping system of this invention liquid cooling system. It is a schematic diagram which shows the example of the other form of the heat receiving part of this invention liquid cooling system. It is a schematic diagram which shows the example of the other form of the piping system of this invention liquid cooling system. It is a schematic diagram which shows the example of the other form of the piping system of this invention liquid cooling system. It is a schematic diagram which shows the example of the other form of the heat receiving part of this invention liquid cooling system. It is a schematic diagram which shows the example of the other form of the piping system of this invention liquid cooling system. It is a schematic diagram which shows the example of the other form of the piping system of this invention liquid cooling system. It is a schematic diagram explaining the example of the structure of the flow control unit of the example of FIG.9 and FIG.10.

Explanation of symbols

2 ... heating element, 3 ... heat receiving part 3, 4 ... heat dissipation part, 5 ... circulation pump, 6 ... pipe, 7 ... tube

Claims (6)

In a liquid cooling system having a plurality of heat generating parts,
A heat receiving part that absorbs heat from the heat generating part;
A refrigerant that removes the heat from the heat receiving portion by heat exchange;
A heat dissipating part that dissipates the heat from the refrigerant by heat exchange;
The heat receiving portion and the heat radiating portion are connected to each other, and the filled refrigerant is configured to be freely circulated.
The liquid cooling system, wherein at least one of the plurality of the heat receiving units provided is connected by the pipe in parallel with the other heat receiving units. The liquid cooling system according to claim 1,
A liquid cooling system in which the refrigerant is circulated by a pump disposed in the pipe. The liquid cooling system according to claim 1,
A liquid cooling system comprising a flow rate adjusting mechanism for the refrigerant in the pipe. In an electronic device having a liquid cooling system for cooling a plurality of heat generating components,
A heat receiving part that absorbs heat from the heat generating part;
A refrigerant that exchanges heat and removes the heat from the heat receiving unit;
A heat dissipating part that dissipates the heat from the refrigerant by heat exchange;
The heat receiving portion and the heat radiating portion are connected to each other, and the filled refrigerant is configured to be freely circulated.
An electronic apparatus having a liquid cooling system, wherein at least one of the plurality of the heat receiving portions provided is connected to the other heat receiving portions in parallel with the pipe. In the electronic device which has the liquid cooling system of Claim 4,
An electronic apparatus having a liquid cooling system, wherein the refrigerant is circulated by a pump disposed in the pipe. In the electronic device which has the liquid cooling system of Claim 4,
An electronic apparatus having a liquid cooling system, wherein the pipe is provided with a flow rate adjusting mechanism for the refrigerant.

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