JPS5917559B2 - Cooling methods for electronic equipment - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a cooling method for electronic devices using a jet stream.

■0 In semiconductor-based electronic devices, in order to improve performance or downsize, it is necessary to improve the degree of integration.
It is necessary to increase packaging density, and the accompanying increase in thermal density requires higher cooling capacity.

As a conventional cooling method for electronic devices, the one shown in FIG. 54 is known, for example. In the figure, 1-1 to 1-3 are printed boards equipped with electronic components, 2-1,
2-2 indicates a cooling fan. Although the printed circuit board is not shown, it is mounted on a rack. As shown by the arrow, in this type of parallel airflow cooling method, the airflow passes between the printed boards
The limit is c to 20 m/sec, and since a large fan is used, noise problems arise. In addition, the heat transfer coefficient of parallel airflow is from several tens to hundreds of tens of thousands KC0j/771
It has a disadvantage that the cooling capacity is smaller than that of liquid cooling.Furthermore, as can be seen from Fig. 4, the upper printed board groups 1-1 and 1-2 are Since the parts are cooled by the air flow warmed by the lower printed board group 1-3, the temperature of the parts increases as the air temperature rises, and the parts are not cooled sufficiently.

A liquid cooling system in which a cooling plate is attached to a printed board and the cooling plate is cooled with a cooling medium does not have the above-mentioned drawbacks, but it does have problems in terms of cost and maintenance.

The present invention is based on the above consideration, and an object of the present invention is to provide a cooling method for electronic devices that has excellent cooling capacity and is easy to maintain.

Therefore, the electronic device cooling method of the present invention includes an electronic device configured by mounting a plurality of electronic components on a substrate and having a surface parallel to the surface of the substrate, and a plurality of dinit flow jetting nozzles. A dinit header configured from an isobaric container and a piping system for supplying compressed gas to the dinit header, the dinit header is arranged so as to overlap the board of the electronic device, and the dinit header is arranged to overlap with the board of the electronic device. The dinit stream ejected from a plurality of dinit stream jetting nozzles is made such that a free dinit stream portion of the dinit stream has a vertical component with respect to the surface of the substrate, and is sprayed onto a locally temperature-rising portion of the electronic device. It is characterized by this. ? The present invention will be explained below with reference to the drawings. FIG. 1 is a perspective view of one embodiment of the present invention, and FIG. 2 is a block diagram of air source equipment.

In Figure 1, 1 is a printed circuit board, 3 is an electronic component, and 4 is a printed circuit board.
5 indicates a dinit header, 5 indicates an isobaric container, 6 indicates a nozzle, and 7 indicates an air introduction pipe. The electronic component 3 is, for example, an IC.
The size of the chip, which is a chip or an IC package and is a heating element, is 1 mm square to several mm square.

The air introduced from the air introduction pipe 7 is ejected from the nozzle 6 as a dinit flow. The cross-sectional shape of the nozzle 6 can be circular, slit, or irregularly shaped, such as a cross. The dinit stream is blown directly onto the electronic component 3, which is the area where the local temperature rises. One nozzle 6 is used for one part.
Alternatively, a plurality of nozzles 6 may be provided to correspond to one electronic component in consideration of clogging of the nozzles 6. Further, if the IC chip, that is, the electronic component 3 is small, one nozzle 6 may correspond to a plurality of electronic components. The dinit flow consists of a free dinit flow section, an impinging dinit flow section, and a wall dinit flow section, but does the free dinit flow section mean that the dinit flow collides with a wall? The impingement dinit flow section refers to the dinit flow section at the collided section, and the wall dinit flow section refers to the dinit flow section that flows along the wall after the collision.
The most heat is removed from the electronic component 3 in the impingement dinit flow section. By vertically spraying the dinit flow, the air boundary layer on the surface of the cooling object becomes thinner, so the heat transfer coefficient of the dinit flow is from several hundred to several thousand K? /IHr・
℃, which is an order of magnitude higher than the heat transfer coefficient of parallel air flow.
When the dinit flow is blown perpendicularly to the substrate 1, the maximum cooling efficiency is obtained when the distance between the substrate 1 and the nozzle 6 is H and the nozzle diameter is D.

Of course, the dinit stream may be sprayed obliquely onto the substrate 1 in order to perform the exhaust smoothly. FIG. 5 is an explanatory diagram of a second embodiment of the present invention.

In the case shown in FIG. 1, the dinit stream is directly blown onto the electronic components 3, but if the substrate 1 is made of a material with good thermal conductivity, such as alumina porcelain or beryllia porcelain, the dinit stream is blown directly onto the electronic components 3. Instead of spraying, it is also possible to spray the dinit stream onto the back surface of the substrate 1. At this time, it goes without saying that if the dinit stream is sprayed at a position corresponding to the mounting position of the electronic component 3 or a group of electronic components 3, the electronic component 3 can be efficiently cooled.

In addition, in the one shown in FIG. 1, the nozzle 6 is provided only on one side of the isobaric container 5, but the nozzle 6 is provided on both sides.
The dinit flow may be sprayed onto two substrates 1 using two headers.

Note that when air is blown out from the nozzle 6 as a dinit flow, the air temperature decreases due to adiabatic expansion. All you have to do is increase the pressure difference.
Of course, it is also possible to configure the board and the header integrally, and in this case, it becomes possible to remove the board while cooling it during maintenance or the like.

Figure 2 shows the air source equipment used in the present invention.
8 is an intake filter, 9 is a compressor and a compressor, 10
11 represents a pressure gauge, 11 represents an air chamber 12 represents a distributor, and 13 represents a valve. The air is purified by an intake air filter 8, compressed by a compressor or compressor 9, and stored in an air chamber 11. air chamber 1
1 is read by a pressure gauge 10. Air in the air chamber 11 is sent to each unit via a valve 13. Each unit has a distributor 12 which distributes air to each header. When the air is compressed by the compressor 9, the air temperature rises, and in order to dissipate the heat of the air whose temperature has increased to the outside, a heat radiation fin (not shown) may be provided in the middle of the piping. FIG. 3 shows another embodiment of the header, in which 5' indicates a pipe-shaped isobaric container.

The difference from the one in Fig. 1 is that the one in Fig. 1 has one box-shaped isobaric vessel 5, whereas the one in Fig. 3 has a plurality of pipe-shaped isobaric vessels 5'. This is the only point that has .
FIG. 6 is a sectional view of a third embodiment of the present invention.

In the same figure, reference numeral 14 indicates a dinit film having a double-layered intake and exhaust part.
15 is an exhaust pipe, 16 is an air introduction pipe, 17 is an intake chamber, 18 is an exhaust chamber, 19 is a partition, 20 is a nozzle, and 21 is an opening. A plurality of nozzles 20 protrude from the partition wall 19. The ends of these nozzles 20 protrude outward from the upper surface of the dinit header 14 and face the electronic components 3 mounted on the board 1. A plurality of openings 16 are provided in the top surface of the dinit header 14. Pressurized air introduced into the intake chamber 17 from the air introduction pipe 16 is blown onto the electronic component 3 through each nozzle 20 . Air warmed by the heat of the electronic component 3 enters the exhaust chamber 18 through the opening 21 and is exhausted through the exhaust pipe 16. ? As is clear from the above explanation, the electronic equipment cooling method of the present invention has the following advantages: (a) dinit flow provides heat conductivity comparable to liquid cooling, which is close to the limit value of air cooling, and (b) special refrigerant is used. (c) The piping system for air distribution can be separated from the board, making it easy to maintain; (d) The rise in air temperature inside the rack can be ignored, and all parts can be cooled with air at a constant temperature. (e) It is possible to intensively cool the localized temperature-rising parts of semiconductor chips, etc., (f) as a result, higher packaging density is allowed compared to conventional air-cooled mounting, and (g) the overall system configuration is simplified. It has excellent effects such as being able to be made compact and compact.

[Brief explanation of the drawing]

Fig. 1 is a perspective view of one embodiment of the present invention, Fig. 2 is a block diagram of the air source equipment, Fig. 3 is a side view of another example of the header, and Fig. 4 is a perspective view of one embodiment of the present invention.
5 is an explanatory diagram of a conventional example of a cooling system for an electronic device, FIG. 5 is an explanatory diagram of a second embodiment of the present invention, and FIG. 6 is a partially sectional view of a third embodiment of the present invention. 1... Printed circuit board, 3... Electronic components, 4... Dinit header, 5... Equal pressure container, 6... Nozzle , 7... Air introduction pipe, 14... Genit header having two-layer intake and exhaust part, 15... Exhaust pipe, 16...
Air introduction pipe, 17...Intake pipe, 18...
- Exhaust chamber, 19... partition, 20... nozzle, 21... opening.

Claims (1)

[Claims] 1. An electronic device configured by mounting a plurality of electronic components on a substrate and having a surface parallel to the surface of the substrate, and an isobaric container provided with a plurality of jet stream ejection nozzles. a jet header and a piping system for supplying compressed gas to the jet header, the jet header is arranged so as to overlap the substrate of the electronic device, and a plurality of jet streams are ejected from the jet header. An electronic device characterized in that the jet stream ejected from the nozzle is configured such that a free jet stream part of the jet stream has a vertical component with respect to the surface of the substrate, so that the jet stream is blown onto a locally increased temperature area of the electronic device. Equipment cooling method. 2. The method of cooling an electronic device according to claim 1, wherein the jet header is constructed and arranged to spray one or more jet streams onto each electronic component. 3. The electronic device according to claim 1, wherein the jet header is configured and arranged to spray one or more jet streams to the backside position of the board corresponding to the mounting position of each electronic component. Equipment cooling method. 4. The method for cooling an electronic device according to claim 1, wherein the jet head is constructed and arranged to spray one jet stream onto a plurality of electronic components. 5. The jet head according to claim 1, wherein the jet head is configured and arranged to spray one jet stream onto the back side area of the board corresponding to the mounting area of one group of electronic components. Cooling method for electronic equipment.