Electricity: conductors and insulators – With fluids or vacuum – With cooling or fluid feeding – circulating or distributing
Patent
1994-03-29
1996-12-10
Thomas, Laura
Electricity: conductors and insulators
With fluids or vacuum
With cooling or fluid feeding, circulating or distributing
361709, 361720, H05K 720
Patent
active
055833160
DESCRIPTION:
BRIEF SUMMARY
TECHNICAL FIELD
The present invention relates to a cooling device for cooling a heat-generating element or a heat-generating unit, that is, a heat sink system, more particularly relates to a heat-generating element cooling device for cooling a heat-generating element or heat-generating unit such as a high density integrated circuit package.
BACKGROUND ART
Relative small sized, but multi-functional and high performance electronic equipment such as personal computers (PCs), work stations, and other desktop type or desk-side type computers make use of high density integrated circuit packages. These become local sources of heat. Usually, heat-radiating fins are provided individually or in common for such high density integrated circuit packages. Use is made of natural cooling by natural ventilation or forced cooling by common cooling fins for the equipment as a whole so as to cool the same along with other elements and units.
Some recent high integration LSI packages give off several watts of heat. Further, along with the rise of the clock frequency used, the amount of heat generated increases. In particular, it is sometimes not possible to obtain sufficient cooling with the above type of usual heat sink in the case of an LSI package generating from 5 to 6 or more watts of heat. As the cooling fans for forced cooling, use is made of, for example, 60 to 80 mm square sized fans for the above-mentioned desktop type personal computers or 120 mm square sized fans for desk-side type computers, operated at a considerably high speed of, for example, 3000 to 5000 rpm. Use of ones with more powerful cooling capacities is not possible in view of the size of the equipment, costs, and noise.
That is, if the fans are made larger in size, the size of the equipment increases accompanying this, the costs increase, and the noise increases as well, but the cooling capacity does not increase commensurate with the same. Further, even if a number of fans are used arranged in series or in parallel, the size of the equipment and the costs increase in accordance with this, but the resultant amount of cooling air does not similarly multiply. Further, operating the fan at a higher speed is difficult in view of the noise. Also, even if a large sized fan is operated at a low speed, the merits in terms of cooling effect and noise commensurate with the demerits of the equipment size and costs cannot be obtained. For these reasons, as a result, it is not possible to supply sufficient cooling air for the heat sink of a high heat generating LSI package for example as mentioned above.
For example, a conventional example of the case of cooling a printed circuit board mounted in high density mounting electronic equipment is shown in FIG. 1. In this conventional example, cooling fans 17 are arranged in a shelf 15 of the electronic equipment for cooling the printed circuit boards 16, 16 . . . housed in the shelf 15. When heat-generating elements 1 are mounted on the printed circuit boards 16, 16 . . . , it is necessary to increase the efficiency of cooling the heat-generating elements 1 by affixing known heat sinks provided with a plurality of heat-radiating fins to the heat-generating elements 1.
Note that in FIG. 1, 19 shows connectors for mounting the printed circuit boards 16 to a back panel, while 20 shows an air duct.
The main object of a heat sink is to increase the heat conducting area. If trying to obtain a high heat radiating effect, the height of the heat-radiating fins must be made greater or the interval between the heat-radiating fins must be made narrower, but in an actual board, this would lead to a reduction in the mounting density and an increase in the fluid resistance and thus would cause the problem, it has been pointed out, of not being able to obtain the required performance.
Further, even with cooling by a cooling fan 17, it is not possible to cool just a specific heat-generating element 1 on a spot basis. When a certain air speed or more is already obtained, there is the problem that the demerit of the greater noise bec
REFERENCES:
patent: 3566958 (1971-03-01), Zelina
patent: 4469970 (1994-09-01), Neumann
patent: 4568846 (1986-02-01), Kapadia
patent: 4835658 (1989-05-01), Bonnefoy
patent: 4940085 (1990-07-01), Nelson et al.
patent: 4949219 (1990-08-01), Moriizumi et al.
patent: 5309983 (1994-05-01), Bailey
patent: 5365400 (1994-11-01), Ashiwake et al.
patent: 5384687 (1995-01-01), Sano
Kerjilian, Q. K. et al; "Heat-pipe cooled stacked electronis wafer package"; IBM Technical Disclosure Bulletin: vol. 18, No. 12: May 1976: p. 3982.
Patent Abstracts of Japan, vol. 8, No. 181 (E-261) [1618], 21 Aug. 1984 & JP-A-59 072968 (Fanuc) 25 Apr. 1984.
Patent Abstracts of Japan, vol. 8, No. 161 (E-257) [1598], 26 Jul. 1984 & Japan-A-59 059057 (Fanuc) 4 Apr. 1984.
`An enchantment of heat sink using air collector and duct` Research Disclosure No. 330, Oct. 1991, Emsworth, GB, p. 813, XP265060, *the whole document*.
`Air-cooling modular package` IBM Technical Disclosure Bulletin, vol. 21, No. 11, Apr. 1979, New York, pp. 4485-4486, U. P. Hwang et al.
Kitahara Takashi
Shimanuki Tadayoshi
Machtinger Marc D.
PFU Limited
Thomas Laura
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