JPH0362039B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a forced air cooling structure in an electronic device such as an information processing device.

[Conventional technology]

Conventionally, when a device is configured with a large number of elements such as an information processing device, as shown in FIG.
In many cases, a structure is adopted in which an electronic circuit package mounted on a printed board 1b is arranged three-dimensionally. Fifth
In the example shown in the figure, the electronic circuit package 1 is housed in the frame 7 by stacking four units 21 as electronic circuit units arranged on the motherboard 3 via the connectors 2. Air blowing units 4 and 5 equipped with a plurality of blowers 6, such as axial type blowers, are arranged above and below the frame 7, respectively, and covers 8 are fixed to the frame 7 at each stage. The lower blower unit 4 sends outside air into the apparatus, and the upper blower unit 5 exhausts air warmed by the element 1a inside the apparatus to the outside of the apparatus, thereby cooling the element 1a so as not to exceed a specified temperature. Figure 6 shows the BB cross section of Figure 5.
The wind flows from the bottom to the top as shown by the arrow. here
Each time it passes through the electronic circuit package 1 in stages (a) to (d), ΔT ₁ , ΔT ₂ ,
ΔT ₃ , ΔT ₄ temperature increases. Therefore, the temperature T ₄ of the electronic circuit package 1 located in the (2) stage takes in the air warmed by the element groups in the (a), (b), and (c) stages mounted upwind from itself. Therefore, the temperature T ₄ is expressed by the following equation.

T ₄ =T ₀ +∆T ₀ +∆T ₁ +∆T ₂ +∆T ₃ +∆T ₄ …(1) Here, T ₀ is the temperature of the air that the device takes in from the outside,
ΔT ₀ is the temperature rise due to heat from the blower. In this way, the temperature of the electronic circuit package 1 at the top level is the sum of the temperature rises from the bottom level, so
The cooling performance was very inefficient, and it was necessary to send a large amount of air into the device in order to maintain the element 1 at a specified temperature or lower and to realize a highly reliable device.

[Problems to be solved]

However, this led to an increase in the size of the blower 6 and increased noise generated by the blower 6. Naturally, due to the capacity and noise limitations of the blower 6, there was a problem in that it was not possible to cool elements that generated a large amount of heat, and this became a major obstacle in the design of the device, which aimed to increase the packaging density and improve the performance.

[Means for solving problems]

The present invention solves the above problems,
A plurality of electronic circuit units each having at least a heating element are housed in a frame in a predetermined direction in a multi-stage manner, and blowers are disposed at both ends of the frame in the predetermined direction, and A cooling structure for an electronic circuit device in which a group of circuit parts is covered with a duct, and the pair of blowers blows air into the duct to cool the group of electronic circuit parts, wherein a hole is provided in the middle of the duct, and the pair of blowers blows air into the duct to cool the group of electronic circuit parts. Accordingly, the duct is configured to send air from both ends of the frame toward the holes, or from the holes toward both ends of the frame.

〔Example〕

Next, the embodiment will be described with reference to FIGS. 1 to 4.

1 and 2 are respectively a perspective view of an electronic device to which an embodiment of the cooling structure for an electronic device according to the present invention is applied, a longitudinal sectional view taken along line A-A in FIG.
4 are a perspective view and a cross-sectional view, respectively, of the electronic device to which another embodiment of the above cooling structure is applied.

In the figure, a unit 21 serving as an electronic circuit section, which is made up of an electronic circuit package 1 in which an element 1a is mounted on a printed board 1b and arranged on a motherboard 3 via a connector 2, is housed in a frame 7 in a multi-stage manner, and air blowing units are arranged above and below. 4 and 5 and the cover 8 is fixed to the frame 7 is the same as the conventional system described above. However, in the present invention, the upper blower unit 5 is installed upside down compared to the conventional case, so that the blower 6 causes the air to flow from top to bottom. Further, a hole 9 is provided in the cover 8 at the center of the stage, and flat guide plates 8a and 8b are attached diagonally to the cover 8 at an acute angle as shown in FIG. 2 on the back side of the cover 8. Further, a flat partition plate 8c is provided at the boundary between the (b) stage and (c) stage at right angles to the frame frame 7.

Next, using FIG. 2, the flow and temperature of the wind will be explained. The wind flows as shown by the arrow. That is, after the heat is transferred from bottom to top over the electronic circuit packages 1 in the lower stages (a) and (b) by the lower air blower unit 4, the direction is corrected at right angles by the guide plate 8b and the partition plate 8c. and is exhausted from the hole 9.
On the other hand, for the electronic circuit packages 1 in the upper (C) and (D) tiers, the air flows from top to bottom by the upper blower unit 5, and is directed outward through the holes 9 by the guide plate 8a and the partition plate 8c, as in the lower tier. Exhausted. Note that the blower unit 4,
The ventilation resistance of the electronic circuit package group for No. 5 is the same as the conventional one, and the same air volume can be obtained.
Each temperature rise ΔT ₀ to ΔT ₄ shown in the figure is the same value as the conventional one. The maximum temperature is indicated on the electronic circuit package 1 mounted in stages (B) and (C), and the temperature is
When T ₂ and T ₃ are assumed, it is expressed by the following formula.

T ₂ =T ₀ +ΔT ₀ +ΔT ₁ +ΔT ₂ …(2) T ₃ =T ₀ +ΔT ₀ +ΔT ₄ +ΔT ₃ …(3) Compared to equation (1) described in the conventional technology, T ₂ is (ΔT ₃ +ΔT ₄ ), T ₃ is smaller by the value of (ΔT ₁ +ΔT ₂ ). That is, this shows that the influence of temperature rise due to the electronic circuit package 1 located upwind has become smaller than in the past. The first embodiment described so far is an example of a three-dimensionally arranged structure, but the second embodiment is an example of a two-dimensionally arranged planar mounting shown in FIGS. 3 and 4. shows.

A unit 13 is constructed by mounting a large number of elements 11 as electronic circuit parts each having a heat sink 11a on a printed board 12, and a blower 14 such as a cross-flow fan that generates flat air on the left and right sides of this unit 13, 15 is attached.

The left blower 14 directs the wind from left to right,
The right blower 15 is installed so that the air flows from right to left.
Further, a flat guide plate 16a, 1 has a hole 17 in the center and is installed obliquely inside near the hole 17.
6b and a duct 16 having a plate-shaped partition plate 16c which divides the hole into two and is attached at right angles, covers the element 11. Here, the wind flows from the left and right toward the center as shown by the arrows in FIG.
The direction is corrected by the partition plate 16b and the partition plate 16c, and the air is exhausted from the hole 17. The highest temperature appears on the elements at positions (c) and (d), but for the same reason as the embodiments shown in Figs. 1 and 2, the effect of temperature increase due to heat in the element 11 located upwind is Since the temperature can be reduced, it is possible to keep the temperature lower than before. That is, in each of the above embodiments, the number of electronic circuits arranged in series per cooling system is halved compared to the conventional unidirectional air blowing system, and therefore the temperature rise is also reduced to halved. This shows that while using the same blower as the conventional blower and maintaining the same noise level as the conventional blower, it has a cooling capacity that generates about twice as much heat. Although this embodiment is an example in which air is sent into the equipment unit,
A similar effect can be obtained with a structure in which all flows are reversed, such as exhausting air from inside the device.

〔Effect of the invention〕

As explained above, in the present invention, a group of electronic circuits is wrapped in a frame and a duct, and air blowers provided at both ends of the frame cool the group by blowing air between the ends and between the holes in the middle of the duct. Therefore, it is possible to reduce the number of electronic circuit groups lined up per wind cooling system, thereby suppressing the temperature rise of the electronic circuit groups, improving performance, and relatively reducing the size of the equipment. This has the effect of reducing the size, improving the packaging density of the electronic circuit group, and widening the range of applications.

[Brief explanation of drawings]

1 and 2 are respectively a perspective view of an electronic device to which an embodiment of the cooling structure for an electronic device according to the present invention is applied, a longitudinal sectional view taken along line A-A in FIG.
5 and 4 are a perspective view, a cross-sectional view, and a cross-sectional view, respectively, of the electronic device to which another embodiment of the cooling structure is applied.
6 are a perspective view of an electronic device to which a conventional electronic device cooling structure is applied, and B--B in FIG. 5, respectively.
It is a longitudinal sectional view along line B. 1...Electronic circuit package, 1a, 11... Element,
1b, 12...Printed board, 2...Connector, 3...Motherboard, 4,5...Blower unit, 6,14,
15...Blower, 7...Frame, 8...Cover, 8a, 8
b, 16a, 16b...Guidance plate, 9, 17...Hole, 8
c, 16c...Partition plate, 11a...Heat sink, 1
3, 21...unit, 16...duct.

Claims (1)

[Claims] 1. A plurality of electronic circuit units each having at least a heating element are housed in a frame in a multi-stage manner in a predetermined direction, and blowers are disposed at both ends of the frame in the predetermined direction, and A cooling structure for an electronic circuit device in which a group of electronic circuit parts is covered with a duct, and the pair of blowers blows air into the duct to cool the group of electronic circuit parts. By the blower,
A cooling structure for an electronic device, characterized in that the duct is configured to send air from both ends of the frame toward the holes, or from the holes toward both ends of the frame.