JPS59152695A - Method of cooling printed board - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to an improvement in a method for cooling a printed circuit board mounted in an electronic device.

First, a conventional cooling method will be briefly explained using FIG. In the figure, /1) is a printed circuit board guide, and there is a guide groove (2) for inserting the printed circuit board (2).
3), and is connected to the chassis +41 with screws or the like.

At the rear of the printed circuit board guide (1), there is a connector (
A motherboard (6) having a motherboard (5) is installed, and a printed circuit board connector (7) at the rear end of said printed circuit board (2).
It is designed to mate with the

Each of the printed circuit board guides (1) has ventilation holes (8
), and a fan (not shown) provided below the printed circuit board guide (1) blows cooling air between the printed circuit boards (2) to cool them down.

However, the above-mentioned method of cooling a printed circuit board has the following drawbacks.

First, because the conventional method uses forced air convection using a fan, its heat exchange capacity is limited.

It has become impossible to obtain the amount of heat exchange required to deal with the high heat generation density that has accompanied the recent increase in the integration density of electrical components and miniaturization of devices, and the reliability of electronic devices has deteriorated. This had the drawback of causing a major problem.

Also, when one device is used in a place with a bad environment.

Since the conventional method uses forced convection of cooling air introduced from outside the device, even if the air is purified to some extent by an air filter, dust gradually accumulates around the printed circuit board (2). As a result, during the second inspection of equipment maintenance, during the process of attaching and detaching the printed circuit board (2), dust entered the mating contacts of the connector (5) and the printed circuit board connector (7), causing malfunctions, poor connections, etc. to cause.

It also has drawbacks such as troublesome maintenance to prevent clogging of the air filter, resulting in a decrease in reliability and maintainability as an electronic device.

This invention was made to improve the above-mentioned conventional drawbacks, and will be explained in detail below with reference to embodiments shown in FIGS. 2 to 4.

In the figure, (1) is a printed circuit board guide.

As shown in FIG. 3, which is a partial cross-sectional view of FIG.

The thin movable part (9), which is formed into a U-shape by a thin sheet of metal that can be expanded, is attached to the inner surface, and the thick fixed part of the ring is attached to the outer surface. There is a liquid inlet hole (ID) at its rear as shown in the figure.

It has a liquid discharge hole +la at the front. OJ is the high temperature side manifold, and (14) is the low temperature side manifold.

As shown in FIG. 3, each is joined to match the liquid inlet hole fil) and the liquid discharge hole α2 of the printed circuit board guide (1), and can be provided as an external function through the piping joint 051 and the piping hole, respectively. A certain heat dissipation part,
and connected to the pump.

The printed circuit board (2) is provided with heat transfer planes (17+) on both ends of the printed circuit board (2) in the insertion direction to conduct heat from the electrical components, as shown in Fig. 4. As shown in FIG. 3, the heat transfer plane 0 is in surface contact with the thin movable portion (9).

The decoy is a cooling liquid, and the above piping Oe and piping joint l-
The cooling liquid 0 gJ that has entered the manifold 04 on the low temperature side through f151 is divided into the plurality of printed circuit board guides (1) through the liquid inlet hole (11) and reaches the liquid discharge hole α2. In the meantime, the above heat transfer plane 0
71 and the thin-walled movable part (9), the heat from the electrical components of the printed circuit board (2) is transferred to the high-temperature side manifold 03). 05) and piping 161 to an external heat radiating section, and is circulated by a pump.

The pump is turned on by a switch installed near the insertion part of the printed circuit board (2).

The switch can be turned OFF when the printed circuit board (2) is attached or removed, and the switch can be turned ON after it is mounted in a fixed position.

According to the cooling method of this printed circuit board as explained above, it is a 9 indirect conduction liquid cooling type, and when heat exchange is truly required during normal operation of 9 devices by operating a switch, the cooling liquid (181 Due to the inflow of water, the thin movable part (9)
By applying liquid pressure to push and spread the heat transfer plane from the inside, the contact surface pressure between the thin movable part (9) and the heat transfer plane 0η increases, resulting in a reduction in contact thermal resistance and more effective heat exchange. By being able to do this, it is possible to obtain a larger amount of heat exchange than with conventional methods, and to be able to fully respond to the high heat generation density that comes with the high integration of one part and the miniaturization of equipment. This makes it possible to improve the reliability of the electronic device.

In addition, since it is a two-direction conductive liquid cooling system, there is no need to introduce air from outside the nine devices, making it possible to have two devices in a sealed structure, which eliminates malfunctions and poor connections due to dust that occur with conventional methods. .

The hassle of air filter maintenance is eliminated, and reliability and maintainability as a single device can be improved.

[Brief explanation of the drawing]

Figure 1 is a diagram showing the conventional cooling method for printed circuit boards, Figure 2
The figure shows a method for cooling a printed circuit board according to the present invention.
3 is a partial sectional view of FIG. 2, and FIG. 4 is a detailed view of the printed circuit board in FIG. 2, where (1) is a printed circuit board guide and (2) is a printed circuit board. (3) is the guide groove, C4) is the chassis, and (5) is the connector. (6) is the motherboard, and (7) is the printed circuit board connector. (8) is a ventilation hole, (9) is a thin movable part, 001 is a thick fixed part, +3υ is a liquid inlet hole, 0'A is a liquid discharge hole, 0
31 is the high temperature side manifold, 041 is the low temperature side manifold, Q51 is the piping joint I-, 061 is the piping,
071 is a heat transfer plane. The decoy is a coolant. Note that the same or corresponding parts in the two figures are designated by the same reference numerals. Agent Makoto Kuzuno - 1st figure nail 2rR happy 4 N 7

Claims (1)

[Claims] A heat transfer plane for guiding heat from electrical components. Inserting a printed circuit board having a printed circuit board on both sides of both end portions in the insertion direction into a printed circuit board guide having a U-shaped cross section, a thin movable portion on the inner surface side, and a thick fixed portion on the outer surface side, Cooling fluid is poured into the printed circuit board guide from a manifold connected to the printed circuit board guide using a pump linked with an external switch, and the thin wall expands due to the internal hydraulic pressure, causing the heat transfer plane and the thin movable section to flow together. Increase the contact pressure between. A method for cooling an indirect conduction liquid-cooled printed circuit board, characterized in that the contact portion is used as a heat transfer path.