JP2000349480A - Cooler of heat generating element - Google Patents

Abstract

PROBLEM TO BE SOLVED: To cool respective heat generating elements at a uniform temperature, by covering with a sealing case the plurality of heat generating elements mounted on a printed circuit board, and by forming in the sealing case independent shunts of each other for the respective heat generating elements. SOLUTION: On one surface of a printed circuit board 1, a plurality of heat generating elements 2 are mounted to form independent cooling shunts 8 of each other for these respective heat generating elements by partition plates 7 formed on the rear side of a sealing case 3. Further, the temperatures of the cooling liquids flowing in these respective cooling shunts 8 are so set to the same temperature of 25 deg.C in the states of them contacting with the respective heat generating elements 2 that the junction temperatures of all the heat generating elements 2 are maintained resultly at the same temperature of 70 deg.C. Thereby, there is completely no possibility of the heat generating elements 2 malfunctioning partially due to the temperature differences among them to constitute a highly reliable cooler.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a heating element cooling device applied to a large-scale electronic device, and more particularly to a heating element cooling device for cooling a plurality of heating elements with a common insulating cooling liquid.

[0002]

2. Description of the Related Art FIGS. 5 and 6 show the structure of a conventional heating element cooling device. In the drawing, reference numeral 1 denotes a printed circuit board. In this example, as shown in FIG. 6, an example is shown in which the heating element 2 is mounted on both the front side 1A and the back side 1B of the printed circuit board 1. As the heating element 2, for example, a large-scale semiconductor device called an LSI or the like, a semiconductor switch element used in a power system, or a semiconductor device forming a delay circuit that needs to maintain a constant temperature can be considered.

[0003] A sealed case 3 is placed over a mounting portion of the heating element 2. The sealed case 3 can be formed by die-casting made of aluminum, for example, and is composed of case halves 3A and 3B that are in contact with the front side and the back side of the printed circuit board 1. The case halves 3A and 3B are used to form the printed circuit board 1.
Are sandwiched to form the sealed case 3. Case half 3
O-ring M on the contact surface between A, 3B and printed circuit board 1
(See FIG. 6). A smooth surface such as, for example, a gold plating layer (not particularly shown) is formed on the surface of the printed circuit board 1 at the contact position of the O-ring M, and the O-ring M is pressed against this plating layer to form a liquid-tight structure.

In the sealed case 3, a cooling liquid having a high insulating property such as perfluorocarbon is injected into an inlet 4 and an outlet 5.
It is a structure to flow between. That is, the coolant circulation path 10 is connected to the inlet 4 and the outlet 5. The coolant circulation path 10 cools and circulates the coolant. Coolant circulation circuit 10
Is composed of a heat exchanger 11 and a pump 12, and has a structure in which the coolant is cooled mainly by the heat exchanger 11, returned to a predetermined temperature, and circulated. Connectors J for electrically connecting the heating elements 2 to the outside at both ends of the printed circuit board 1
1, J2 are attached.

[0005]

The conventional sealed case 3 has a common flow path 6 for a plurality of heating elements 2 and has a structure in which a cooling liquid flows through the flow path 6. Therefore, the temperature of the coolant inside the sealed case 3 is, for example, 2 at the inlet 4 side.
For example, a temperature difference of about 5 ° C. and about 35 ° C. is generated at the discharge port 5 side, so that the heating element 2 generates a temperature difference in the contacting coolant depending on its position.
Has the disadvantage that a temperature difference is given between them. That is, assuming that the heating element 2 is an LSI, the LSI
Is disadvantageous in that a temperature difference is given to each device according to its position, and a difference occurs in operating conditions.

SUMMARY OF THE INVENTION An object of the present invention is to provide a heating element cooling device having a structure using a sealed case and circulating a cooling liquid to suppress a rise in temperature, in which a plurality of heating elements can be cooled to a uniform temperature. Is intended to be provided.

[0007]

According to the present invention, a plurality of heating elements mounted on a printed circuit board are covered with a sealing case, and a cooling element is provided in the heating element cooling device having a structure in which a cooling liquid flows in the sealing case. The present invention is characterized in that an independent branch channel is formed for a heating element.

According to the structure of the present invention, the temperature of the coolant flowing in contact with each heating element is the same. As a result,
The advantage is obtained that the plurality of heating elements can be maintained at the same temperature and the operating conditions can be uniform regardless of the difference in position.

[0009]

FIG. 1 shows an embodiment of the present invention. In this embodiment, as shown in FIG.
An embodiment in which a plurality of heat generating elements 2 are mounted on one surface of the device will be described. The present invention is characterized in that a partition plate 7 is formed on the back side of the sealed case 3A, and an independent branch channel 8 is formed for each heating element 2 by the partition plate 7. The partition plate 7 may be formed integrally with the case halves 3A and 3B, or may be configured by mounting a metal plate on the printed circuit board 1.

By adopting a structure provided with the partition plate 7,
The temperature of the cooling liquid flowing through each branch channel 8 becomes the same temperature of, for example, 25 ° C. in a state of being in contact with each heating element 2. As a result, the junction temperature of all the heating elements 2 can be maintained at the same temperature of, for example, 70 ° C., so that an advantage that operating conditions can be uniformed is obtained. FIG. 3 shows a case where the heating elements 2 are mounted on both surfaces of the printed circuit board 1.
Also in this case, the partition plates 7 are formed on both of the case halves 3A and 3B which are in contact with both surfaces of the printed circuit board 1, and the dividing channels 7 are formed by the partition plates 7.

As described above, when the heating elements 2 are mounted on both sides of the printed board 1, holes 1A and 1B are formed in the printed board 1 as shown in FIG. 4, and insulating cooling is performed through the holes 1A and 1B. By flowing the liquid, the cooling liquid can flow over both surfaces of the printed circuit board 1.

[0012]

As described above, according to the present invention, an independent branch channel 8 is formed by each partition plate 7 and a cooling liquid is flowed into each of the branch channels 8 so that all the heating elements 2 are separated. It can be operated under the condition of the same temperature.
Therefore, there is no possibility that a malfunction occurs partially due to a temperature difference, and an advantage that a highly reliable device can be configured can be obtained.

[Brief description of the drawings]

FIG. 1 is a plan view for explaining an embodiment of the present invention.

FIG. 2 is a cross-sectional view taken along line AA of FIG.

FIG. 3 is a sectional view showing a modified embodiment of the present invention.

FIG. 4 is a sectional view taken along the line BB shown in FIG. 3;

FIG. 5 is a plan view for explaining a conventional technique.

FIG. 6 is a sectional view taken along the line CC shown in FIG. 5;

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Printed circuit board 2 Heating element 3 Sealed case 3A, 3B Sealed case half 4 Inlet 5 Discharge port 7 Partition plate 8 Branch flow path

Claims (4)

[Claims] 1. A heating element cooling apparatus having a structure in which a plurality of heating elements mounted on a printed circuit board are covered with a sealing case, and an insulating cooling liquid is flowed in the sealing case to cool the plurality of heating elements. In the sealed case, a plurality of partition plates are provided, a plurality of independent flow paths are formed in the sealed case by the plurality of partition plates, and the heating element is arranged in each of the plurality of flow channels. A cooling device for a heating element, comprising: 2. A heating element cooling device according to claim 1, wherein a plurality of heating elements are mounted on one surface of said printed circuit board, and said heating elements are covered with a sealed case having said shunt channel formed therein. A cooling device for a heating element, comprising: 3. The heat-generating element cooling device according to claim 1, wherein a heat-generating element is mounted on both the front surface and the rear surface of said printed circuit board, and said branch channel is formed on both of said heat-generating element mounting surfaces. A heating element cooling device characterized by having a structure covered with a heating element. 4. The cooling device according to claim 1, wherein the sealing case has an inlet and an outlet for an insulating cooling liquid, and the insulating cooling injected from the inlet. The heating element has a structure in which the liquid flows toward the discharge port through each of the branch channels, and the insulating coolant discharged from the discharge port is cooled by a heat exchanger and circulates in a circulation path injected into the injection port. Cooling system.