JP2009169873A - Cooling structure of computer - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To realize a structure which supplies the most suitable cooling air quantity at a computer system in which a plurality of cases where a plurality of high heating parts are mounted on the same board are mounted in parallel. <P>SOLUTION: The pressure loss of the part with a high load at a heating element on a board 8 is lowered and the pressure loss of the part with a low load at the heating element on the board 8 is raised by installing the air quantity regulating plate 9 consisting of two directional shape-memory alloy which works by temperature of mounted heat sink 2 at intake side or exhaust side. Thus, not only the most suitable cooling air quantity in a case 1 is supplied but also the passing air quantity of the case can be regulated according to necessary cooling air quantity due to load unevenness of a plurality of cases 1 mounted in parallel. <P>COPYRIGHT: (C)2009,JPO&INPIT

Description

  The present invention relates to a method for controlling the air volume particularly for improving the efficiency of cooling each blade in a blade server system and reducing the fan noise of the system.

  In recent years, due to the high heat generation accompanying the improvement in the operation speed of LSIs mounted on electronic computers typified by servers and the like, cooling of devices has become a problem. At the same time, the rise of high-density mounting computers such as blade servers is also a very big problem in terms of device cooling and device noise. In particular, the blade server market used to be a system in which blades with low-heat-generating processors mounted alone were densely integrated, but in recent years, a blade configuration with multiple high-heat-generating and high-performance processors mounted. It has become.

  In order to solve the above problems, high performance fans and high cooling efficiency heat sinks have been developed. Japanese Patent Application Laid-Open No. 2005-286268 discloses a method in which a pressure loss body made of a shape memory alloy is disposed in the exhaust portion of a CPU package of an electronic computer, and the passing air volume of the CPU package is adjusted by the exhaust temperature of the apparatus.

JP 2005-286268 A

  High-performance fans and high-cooling efficiency heat sinks are effective means for all blades installed in the equipment, but blades with low operating rates are overcooled, increasing noise and power. Will be invited. Further, the method disclosed in Japanese Patent Application Laid-Open No. 2005-286268, which is one of the conventional proposals, is a method of changing the pressure loss of the package depending on the exhaust temperature and reducing the air volume when the exhaust temperature is low. When the method is applied to a computer system having two or more high heating elements on one board, a plurality of problems occur.

  In the case of a substrate having two or more high heating elements, their load factors are not necessarily the same, and there are variations, so some heating elements may be hot even if the exhaust temperature is low, The system cannot cool this. If there is not a sufficient distance from the plurality of heating elements, the exhaust temperature will not be uniform and the transformation temperature will not be stable. Furthermore, many blade servers and the like have many connectors mounted on the exhaust part, and are difficult to apply due to physical limitations. Therefore, it is necessary to solve the above-mentioned problem for cooling a system represented by a recent blade server, in which a plurality of high heat generating elements exist on a substrate.

  In order to solve the above problems, the air volume control method according to the present invention includes one or a plurality of shape memory alloy plates that operate according to the heat sink temperature used for cooling the heating element, and gradually reduces the pressure loss. The amount of air passing through the heat sink is adjusted by changing it.

  According to the present invention, the cooling air balance of a plurality of high heating elements mounted on a single substrate can be made efficient. In addition, the pressure loss of the entire computer in which a plurality of housings having the substrates are arranged in parallel can be improved at the same time. In addition, the above efficiency can reduce noise and save power.

  An embodiment of the present invention will be described below with reference to the drawings.

  FIG. 1 shows a form of a blade server on which the heat sink of the present invention is mounted, and FIG. 2 is a perspective view of the inside of the blade housing. A plurality of blade casings 1 including a heat sink 2 for cooling a heating element on a substrate 8 are mounted in parallel and connected to the platter 4 by a connector 3 existing on the substrate 8 inside each blade. Yes. Further, a cooling fan 5 is disposed on the rear side of the platter 4 to supply the cooling air 6 to the entire apparatus and exhaust the exhaust air 7 to the outside of the apparatus. In the present embodiment, four heat sinks 2 for processors, which are high heating elements, are mounted, and are all arranged in parallel for efficient cooling. Further, air volume adjusting plates 9a and 9b using a shape memory alloy are thermally bonded to each heat sink 2. In the present embodiment, one air volume adjusting plate is joined to the base portion on the exhaust side of the heat sink 2, but a plurality of plates having different transformation temperatures may be connected in combination on the heat sink upper part or on the inlet side. For the LSI 10, the HDD 11, the memory 12, and the bus converter 13 that are small heat generating portions on the substrate 8, no air volume adjusting plate is installed.

  When all of the four high heat generation processors are equally loaded, all the air volume adjustment plates do not prevent the cooling air from passing through. However, when some of the processors are in a low load state, the load is low. At the processor position, the air volume adjusting plate 9b is brought into a state to increase the pressure loss. For this reason, it becomes possible to supply more cooling air to other high-load processors. Furthermore, since the pressure loss in units of blades varies depending on the load state by adjusting the pressure loss, the air volume distribution between the blades is also made efficient.

  Conventionally, if the load of even one of the processors increases, it is necessary to increase the number of rotations of the cooling fan 5, so that even when the load viewed from the entire apparatus is low, there is a case where the number of rotations of the fan increases. Even if the fan control is performed, it is conceivable that the apparatus noise does not decrease as expected. By applying the above method to this problem, it is possible to operate at a lower fan speed.

  In general, an apparatus in which a plurality of processors are mounted on a board as shown in FIG. 2 does not necessarily use all the processors, and the number of processors mounted differs depending on the application. In this case, since the heat sink 2 is not required for the socket in which the processor is not mounted, a dummy having the same pressure loss is necessary. However, when the processor is added, this is removed, and surplus parts are generated. In this embodiment, a structure that is mounted with or without a processor, has an air volume adjustment function when the processor is mounted, and functions as a heat sink dummy when not mounted will be described with reference to the drawings.

  FIG. 3 shows an embodiment of the present invention in which the air volume adjustment function is integrated with the heat sink dummy. Two processors inside the blade are installed, and the remaining two are not installed. On the exhaust side of the heat sink 2, a structure 14 made of a bidirectional shape memory alloy that operates at a certain temperature is disposed. When the structure 14 is mounted on the processor, when the temperature of the heat sink 2 is changed from a high temperature to a low temperature exceeding the transformation temperature, the structure 14 changes to a structure that closes the cooling air like the structure 14a. Increase. In addition, when the processor is not mounted, the temperature remains low, so that the flow path is blocked like the structure 14c and serves as a dummy.

  4 and 5 are cross-sectional views of the structure 14a when the heat sink 2 is mounted and the structure 14c when not mounted. A spacer 15 that maintains a constant distance from the heat sink base is joined to the structure. The spacer 15 has a function of conducting the heat sink base temperature to the structure 14, thereby improving the transformation temperature detection accuracy of the structure 14a. Further, the structure 14 a is fixed to the stud 17 press-fitted into the housing 1 using the fixing screw 16 of the heat sink 2. When the processor is not mounted, the structure 14 c is fixed to the stud 17 with the screw 18.

  In a high-density server system that is expected to expand further in the future, especially high-performance blade servers with multiple processors per blade, more efficient air volume distribution can be expected to further reduce noise. It is expected to be applied to a cooling method for high-density, high-reliability electronic computers.

The schematic of the whole apparatus in a claim. The example of mounting of the air volume adjustment board joined to the heat sink in Example 1. FIG. The example of mounting of the air volume adjusting plate also serving as a dummy in the second embodiment. Schematic of the example of the fixing method of the air volume adjustment board which served as the dummy at the time of heat sink mounting. Schematic of the example of the fixing method of the air volume adjusting plate which served as the dummy at the time of heat sink non-mounting.

Explanation of symbols

  DESCRIPTION OF SYMBOLS 1 ... Board fixing housing, 2 ... Heat sink for high heating element, 3 ... Connector, 4 ... Platter, 5 ... Cooling fan, 6 ... Inlet cooling air, 7 ... Exhaust air, 8 ... Main board, 9 ... Heat sink Bonded air volume adjusting plate, 10 ... LSI, 11 ... HDD, 12 ... Memory, 13 ... Bus converter, 14 ... Air volume adjusting plate that also serves as heat sink dummy, 15 ... Spacer, 16 ... Heat sink fixing screw, 17 ... Stud, 18 ... Air volume adjustment plate fixing screw.

Claims (4)

  In an electronic apparatus having a substrate having two or more highly heat-generating parts and a plurality of cases surrounding the substrate arranged in parallel, and having a fan for cooling the system by passing cooling air through the case An electronic computer characterized by dynamically controlling the amount of air flowing through the heat generating portion by means of an air flow control plate made of a bidirectional shape memory alloy that operates according to a heat sink temperature used for cooling the heat generating portion on the substrate.   2. The computer according to claim 1, wherein the air volume distribution corresponding to the load factor of a plurality of heating elements inside the substrate is possible by adjusting the pressure loss by the dynamic fluctuation of the air volume control plate shape.   2. The computer according to claim 1, wherein the air volume can be distributed according to the load variation between the casings arranged in parallel by adjusting the pressure loss by the air volume control plate.   4. The structure according to claim 1, wherein the structure has an air volume adjusting function when the heat sink is mounted, and functions as a heat sink dummy when not mounted.

Images