JPH01175298A - Cooling structure of electronic circuit - Google Patents

Abstract

PURPOSE:To obtain a well-balanced cooling effect, to decrease noise from a cooling machine and miniaturize the enclosure as well, by mounting a cooling plate which is in contact with a highly heat-generating element and is equipped with a liquid cooling medium passage and nozzles which blow air on a low heat-generating element. CONSTITUTION:A flat cooling plate 4 having water channels 4-1 inside the plate is mounted on an upper part of control IC 2 and is fixed at the lower side of a fixing plate 11. A sheet 6 is not only a superior thermal conductor but also a rubber elastic body and comes closely into contact with the lower side of the cooling plate 4 and the upper side of the control IC 2. Heat produced by the control IC 2 is conducted to the sheet 6 and is radiated from the lower side of the cooling plate 4 to water in the water channel 4-1. A plurality of air tubes 7 are mounted at the upper part of memory ICs 3 and nozzles 8 directed towards the memory ICs 3 are placed. Air is blown from the nozzles 8 to the memory ICs 3. The air tubes 7 are fixed at the fixing plate 11. As the cooling is a collision cooling system, its heat transfer coefficient is high and thus its circuit can be cooled by a small quantity of cooled air.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a cooling structure for electronic circuits such as computers.

[Conventional technology]

2. Description of the Related Art In recent years, various information processing devices such as computers have been required to have higher speeds and higher performance.

Along with this, in addition to the higher integration and speed of integrated circuit elements,
BACKGROUND OF THE INVENTION Integrated circuit elements are mounted at high density to reduce signal propagation delay time between integrated circuit elements.

On the other hand, in this type of information processing equipment, the heat dissipation (cooling) method of the integrated circuit elements has a large effect on the performance and reliability of the information processing equipment, so it is difficult to effectively radiate heat from the integrated circuit elements to the outside. This is an important issue.

For this reason, this type of information processing apparatus has conventionally been equipped with a cooling device for integrated circuit elements as shown in FIG. In the figure, the reference numeral 12 designates a frame into which a plurality of circuit boards 1 can be inserted and removed. A plurality of memory ICs 3 and control ICs 2 are mounted on the surface of the circuit board 1, and are cooled by a fan 13 installed on the left side of the frame 12. The outside air is sucked in from the left side of the fan 13 and blown to the memory IC 3 and control IC 2, and the frame 1
Exhaust air to the right side of 2. Here, since the memory IC3 is a MOS, the amount of heat generated is relatively small, but the control IC2 has high integration and high speed in order to exchange signals with the host device at high speed, so the amount of heat generated is significantly larger than that of the memory IC3. It has become.

[Problem that the invention seeks to solve]

By the way, since this type of cooling device for integrated circuit elements is air-cooled, that is, it is cooled by blowing air, its cooling capacity is low, and although it can cool the memory IC3, which generates a small amount of heat, the amount of heat generated is low. big control IC2
The problem was that it could not be cooled sufficiently. Also control I
If the fan 13 is made large in order to cool the memory IC 3, the memory IC 3 will be overcooled, resulting in an imbalance. A large fan generates more noise during operation and requires a larger installation space, resulting in an increase in the size of the equipment housing. Furthermore, when installing a heat sink on the control IC 2, the temperature may not be lowered unless the mounting interval of the circuit board 1 is increased, which is an obstacle to high-density packaging.

The present invention was developed in view of the above circumstances, and is capable of responding to high-density mounting of integrated circuit elements on circuit boards, while also suppressing the noise generated during fan operation to reduce the noise generated during fan operation.
The present invention provides a cooling structure for electronic circuits such as integrated circuit elements, which can cool k-product circuit elements in a well-balanced manner and can reduce the size of equipment casings.

[Means for solving problems]

The present invention provides a cooling structure for an electronic circuit that cools high heat generation elements and low heat generation elements mounted on a circuit board attached to a frame, including: a fixing plate attached to the frame so as to face the circuit board; A cooling plate is attached to the fixing plate and has a flow path through which a liquid refrigerant flows inside and comes in contact with the high heat generation element through a sheet of an elastic material with good thermal conductivity; and an air pipe provided with a plurality of nozzles that blow air toward the low heat generation element.

〔Example〕

Next, the present invention will be explained with reference to the drawings.

FIGS. 1(a) and 1(b) are a longitudinal sectional view and an AA sectional view, respectively, of an embodiment of the present invention.

A plurality of circuit boards 1 are housed horizontally in the frame 12 so as to be freely inserted and removed, and a plurality of control ICs 2 are arranged in the center of the surface of the circuit board 1.
However, memory IC3 is arranged at both ends. The former has a significantly large calorific value, while the latter has a relatively small amount of heat. As means for cooling these ICs, firstly, a flat cooling plate 4 having a water channel 4-1 therein is provided above the control IC 2. The cooling plate 4 is fixed to the lower surface of a flat fixed plate 11 fixed to the frame 12 by screws 11-1 with screws 4-2. However, the screws 4-2 are loosely tightened so that the cooling plate 4 can be moved up and down a little.

Further, the cooling plate 4 is held in the circuit board 1 by the slider 10 and is pressed against the control IC 2 via the sheet 6. The sheet 6 is a good heat conductor and a rubber-like elastic body, and is in close contact with the lower surface of the cooling plate 4 and the upper surface of the control IC 2. The cooling plate 4 has a water inlet pipe 5-1 and a water outlet pipe 5-2 on one side, and when water flows into the water channel 4-1 from the water inlet pipe 5-1, the heat generated in the control IC 2 is transferred to the sheet. 6, and is radiated from the lower surface of the cooling plate 4 to the water in the water channel 4-1.

Since water has a higher cooling capacity than air, the temperature of the control IC 2 can be kept low. Although this embodiment shows an example in which water is used, the present invention is not limited to this, and for example, fluorocarbon liquid may be used as the refrigerant.

Second, a plurality of air pipes 7 are provided above the memory IC 3 as cooling means for the memory IC 3 which generates a relatively small amount of heat.

The air pipe 7 has an air port 9 at one end, is connected to a blower (not shown), and is closed at the other end. The air pipe 7 is bent into a meandering shape as shown in the figure, and is arranged on the left and right parts of the circuit board 1 where the memory ICs 3 are mounted. Furthermore, the air pipe 7 is provided with a nozzle 8 directed toward the memory IC 3.
Air is blown from the nozzle 8 onto the memory IC 3. FIG. 2 is a view taken along arrow B-B in FIG. 1(a), and the memory I
Air is blown over all of C3.

This shows that a plurality of nozzles 8 are provided as shown in FIG.

Air pipe 7 is attached to fixing plate 11 with bracket 7-1 and screw 7-2.
Fixed by

As mentioned above, the memory IC 3 is cooled by air blown from the nozzle 8, and the air is exhausted from side to side through holes provided in the frame 12. Since this embodiment uses an impingement cooling method, it is not possible to cool conventional electronic circuits. Compared to convection-based structures, it has a higher heat transfer coefficient and can be cooled with a small amount of cold air.

With this configuration, even when the circuit board 1 is removed from the frame 12, it is separated from the cooling mechanism by pulling out the slider 10, so that the circuit board 1 can be easily inserted and removed.

〔Effect of the invention〕

As explained above, the present invention provides a first method in which a cooling plate is brought into close contact with a high heat generating element such as a control IC that generates a large amount of heat mounted on a circuit board via an elastic sheet, and a refrigerant is flowed inside the cooling plate. By providing an air pipe with a nozzle on a low heat generation element such as a memory IC that generates a small amount of heat, and providing a second cooling means that cools with the air blown out from the nozzle, it is possible to optimize the temperature according to the amount of heat generated. This allows for balanced cooling. Even if the amount of heat generated increases, there is no need to increase the size of the cooling mechanism; by adjusting the amount of refrigerant and air, electronic circuits such as ICs can be kept at a low temperature, allowing for high-density mounting and downsizing of equipment. can be achieved.

Furthermore, since the low heat generation elements are cooled by an impingement cooling method, the cooling efficiency is good, and since air is distributed in parallel to each element group, a small flow rate is required. Therefore, a small fan is required, and the noise comes only from the nozzle, so low noise can be achieved.

[Brief explanation of the drawing]

Figures 1 (a> and (b) are a longitudinal cross-sectional view and an A-A cross-sectional view of an embodiment of the present invention, respectively, and Figure 2 is a B--B in Figure 1.
B sectional view and FIGS. 3(a) and 3(b) are a longitudinal sectional view and a CC sectional view of a conventional electronic circuit cooling structure, respectively. DESCRIPTION OF SYMBOLS 1...Circuit board, 2...Control ICl3...Memory IC14...Cooling plate, 4-1...Waterway, 4-2...
・Screw, 5-1...Water inlet pipe, 5-2...Water outlet pipe, 6...Seat, 7...Air pipe, 7-1...Bracket, 7-2... Screw, 8... Nozzle, 9...
Air inlet, 10...Slider, 11...Fixing plate,
11-1... Screw, 12... Frame, 13...
fan.

Claims (1)

[Claims] In an electronic circuit cooling structure that cools high heat generation elements and low heat generation elements mounted on a circuit board attached to a frame, a fixing plate attached to the frame so as to face the circuit board; A cooling plate is attached to the high heat generating element through a sheet of an elastic material having good thermal conductivity, and has a flow path through which liquid refrigerant flows inside; 1. A cooling structure for an electronic circuit, comprising: an air pipe provided with a plurality of nozzles that blow out air toward a heating element.