JPH1174428A - Heat sink and its manufacture - Google Patents

Abstract

PROBLEM TO BE SOLVED: To make feasible high performance cooling, by a method wherein heat radiating pieces boring a plurality of aperture parts are numerously juxta posed on a flat plate making the aperture parts oppose to one another, so that the heat radiating piece walls may be thinned to expand the heat transfer area while precisely assuring omnidirectional ventilation. SOLUTION: A heat sink 1 is formed of heat radiating pieces 3 boring a plurality of aperture parts 4 jaxtaposed in a plurality of lines on a flat plate 2. In such a constitution, the aperture parts 4 of adjacent heat radiating pieces 3 are oppositely positioned with one another while the aperture parts 4 of numerously juxtaposed heat radiating pieces 3 are communicated in the rectangular direction to the heat radiating pieces 3. Through these procedures, ventilation in either direction to the heat radiating pieces 3 or the rectangular direction to the heat radiating pieces 3 can be precisely taken so as to increase the heat radiating performance. Furthermore, the heat radiating pieces 3 and the flat plate 2 formed of aluminum are integrally molded, thereby making feasible miniaturizing and light-weighting of the same 3 and 2.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a heat sink for cooling a semiconductor element or a printed circuit board, and more particularly to a thin and lightweight heat sink having an improved heat radiation effect and a method of manufacturing the same.

[0002]

2. Description of the Related Art For example, a heat sink is used to radiate heat generated inside a semiconductor element or the like and to lower a junction temperature to an operating temperature range of the semiconductor element.

[0003] Conventionally, as a heat sink, from the viewpoint of small size, light weight and heat radiation characteristics, for example, as shown in FIG. Is used. Typically, extruded heat sinks are
Coloring process (dyeing, secondary electrolytic coloring, etc.) without surface treatment, anodized, or after anodizing
Is used in a state where it has been surface-treated black.

The semiconductor element is fixed to the surface of the flat plate 17 on the side opposite to the fins 18, and heat generated inside the semiconductor element is radiated through the fins 18 by natural air cooling and forced cooling. Even in the extruded heat sink made of the shape shown in FIG. 12, a high heat radiation effect is exhibited, and the weight is reduced by reducing the thickness w of the fins 18 serving as the heat radiation pieces or by narrowing the fin distance d. In addition, it is possible to improve the heat dissipation performance, but it is difficult to reduce the thickness of the fin to less than 1 mm, for example, in terms of extrudability, and there is a limit in terms of size and weight reduction.

[0005]

SUMMARY OF THE INVENTION The present invention has been made to solve the above-mentioned conventional problems in a heat sink made of an extruded aluminum material.
It is an object of the present invention to provide a heat sink and a method of manufacturing the heat sink, in which the heat radiating piece is thinned, a heat transfer area is enlarged, and ventilation from any direction can be accurately captured to perform high-performance cooling.

[0006]

According to the present invention, there is provided a heat sink in which a plurality of heat radiating pieces having a plurality of openings are arranged on a flat plate such that the openings face each other. It is characterized by being. A second feature is that the heat radiating piece and the flat plate are made of aluminum, and the heat radiating piece and the flat plate are integrally formed.

A method for manufacturing a heat sink according to the present invention comprises:
An aluminum or aluminum alloy profile having an upper wall portion and a lower wall portion and having a plurality of openings vertically arranged through a partition wall portion between the upper wall portion and the lower wall portion is extruded. One of the upper wall and the lower wall of the extruded profile and the partition are cut by a predetermined width at an interval in the lateral direction, and the heat radiation pieces having a plurality of openings are formed so that the openings face each other. A first feature is that a large number of such shapes are arranged on a flat plate.

Further, after a corrugated plate formed into a corrugated shape is inserted in the longitudinal direction of the flat tube into a flat tube formed by bending a plate material and integrated, the flat tubes are spaced apart in the horizontal direction. Radiating piece that has been cut by a predetermined width to form a plurality of openings,
A second feature is that a large number of the openings are formed on a flat plate so as to face each other.

[0009]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS In the present invention, as shown in FIGS. 1 to 3, a plurality of heat radiating pieces 3 having a plurality of openings 4 are arranged on a flat plate 2 in a plurality of rows. Is formed. Reference numerals 5, 6, and 7 denote an upper edge, a middle edge, and a side edge, respectively, that define a plurality of openings 4 provided in the heat radiation piece 3.

The openings 4, 4 of the adjacent heat dissipating pieces 3, 3 are located opposite to each other, and the openings of a large number of heat dissipating pieces are preferably connected to the heat dissipating pieces at right angles to each other. With such an arrangement of the heat radiating pieces and the openings, it is possible to accurately detect the airflow in any of the direction of the heat radiating piece and the direction perpendicular to the heat radiating piece, thereby improving the heat radiating performance. From the viewpoint of miniaturization and weight reduction, it is preferable that the heat radiation piece 3 and the flat plate 2 are made of aluminum, and these are integrally formed.

In the heat sink 1 shown in FIGS. 1 to 3, the openings 4 of the heat radiating pieces 3 are provided in one row. For example, as shown in FIG. 4, the openings 4 of the heat radiating pieces 3 may be provided in two rows. Also, as shown in FIG. 5, a ridge 12 may be provided inside the opening 4 to enhance the heat radiation effect. The ridge is the upper edge 5
Can also be provided outside. Further, as shown in FIG. 6, the opening 4 can be formed by the meandering intermediate edge 13. Can be selected appropriately.

As shown in FIG. 5, a preferred embodiment for manufacturing the heat sink 1 shown in FIGS. 1 to 5 includes an upper wall 9 and a lower wall 10 and an upper wall 9 and a lower wall 10 as shown in FIG. An aluminum profile 8 in which a plurality of openings 4 are arranged in a vertical direction (X direction) through a partition 11 is extruded.

Next, as shown in FIG. 8, the upper wall portion 9 and the partition wall portion 11 of the extruded profile 8 are spaced from each other in the lateral direction (Y direction) by a distance d.
And shaping is performed in parallel with a predetermined width w. As a result, the lower wall portion 10 remains without being cut, and this forms the flat plate 2, and the heat radiation piece 3 having the plurality of openings 4 formed therein.
However, the heat sink 1 having a shape arranged in parallel on the flat plate 2 so that the openings 4 face each other is formed.

A preferred embodiment for manufacturing the heat sink shown in FIG. 6 is to first form a flat tube 14 by bending a plate material such as aluminum as shown in FIG. The corrugated plate 15 made of aluminum or the like is vertically inserted into the flat tube 14, and the end 14 of the flat tube 14 is formed by brazing, welding, or the like.
A and 14B are joined, and the corrugated plate 15 is connected to the flat tube 1
4 and are integrated with each other.

Next, as shown in FIG.
The flat tube 14 fitted with the extruded section 8 shown in FIG.
As in the case of (1), shaping is performed in parallel with a predetermined width w at intervals d in the horizontal direction (Y direction). As a result, the lower wall portion of the flat tube 14 remains without being cut, and this forms the flat plate 2, and the heat radiation piece 3 having the plurality of openings 4 formed therein is
The heat sink 1 having a shape arranged in parallel on the flat plate 2 so that the openings 4 face each other is formed.

In this case, the aluminum plate material forming the flat tube 14 is made of an aluminum alloy core material of Al-Si type,
It is composed of a brazing sheet clad with an Al-Si-Mg brazing material, and the brazing material is formed on both sides of a plate material or a flat tube 1.
4 so as to be clad on the inner surface side, the aluminum plate is bent into the shape shown in FIG. 9, an aluminum corrugated plate 15 shown in FIG. 10 is inserted, fixed with a jig, and brazed. By performing brazing (flux brazing or brazing without flux) by charging the furnace, the joining of the butted ends 14A and 14B of the flat tubes and the joining of the corrugated plate 14 into the flat tubes can be performed simultaneously. it can.

Alternatively, a plurality of heat sinks 16 made of a conventional extruded aluminum material as shown in FIG. 12 are laminated and integrated in a plurality of stages, and then formed in a horizontal direction in accordance with the method shown in FIG. It is possible to manufacture the heat sink of the present invention.

[0018]

Hereinafter, examples of the present invention will be described in comparison with comparative examples. Example An aluminum alloy profile (A6063S) having the shape shown in FIG.
-T5 material, dimensions: height 5 mm, width 100 mm, wall thickness 0.5 mm, number of openings 22), and extrude the extruded profile in the lateral direction (Y direction) as shown in FIG. )
Shaping was performed in parallel at an interval of 5 mm and a width of 1 mm.

As a result, on a flat plate having a thickness of 0.5 mm,
The heat dissipating piece 3 (thickness 1) in which 22 openings 4 surrounded by a 0.5 mm thick upper wall, lower wall and partition are arranged in a line in a row.
mm) were formed side by side at 5 mm intervals.

On the other hand, for comparison, an extruded aluminum alloy material having the shape shown in FIG. 12 (A6063S-T5 material, dimensions: width W is 100 mm, and fin thickness w is 1.2 m at the base)
m, the tip 1 mm, the fin interval d was 5 mm, and the fin height was 8 mm).

Both were 200 mm in length, after anodic oxidation treatment, dyed and black-finished the surface, mounted the semiconductor element on the flat plate surface opposite to the radiating piece and the fin, and compared the heat radiating performance by natural air cooling. The heat sink according to the present invention showed several times the performance improvement compared with the comparative product.

[0022]

According to the present invention, there is provided a heat sink which has a large heat transfer area, has no directivity on the heat radiating surface, can accurately detect ventilation from any direction, and can expect an extremely excellent heat radiating effect. Is done.

Since the hollow extruded material of the flat porous tubular material can be used as the material, it can be made thinner than a conventional flat plate with fins by solid extrusion, and the thickness of the wall portion is less than 1 mm, for example, 0.2 to 0. Since it is possible to manufacture a heat sink having a size of about 0.5 mm, further reduction in size and weight of the heat sink can be expected. Also, since the heat sink of the present invention is thin,
Since the bending process can be easily performed, the installation space can be reduced by, for example, bending the end of the heat sink.

Further, according to the heat sink of the present invention,
Since sufficiently high heat radiation performance can be obtained by natural air cooling, it is maintenance-free and advantageous in cost. According to the forced cooling, a higher heat radiation effect can be obtained. In addition, since it can be manufactured by a combination of extrusion and cutting, it is excellent in mass productivity.

[Brief description of the drawings]

FIG. 1 is a partial perspective view showing one embodiment of a heat sink according to the present invention.

FIG. 2 is a front view of FIG.

FIG. 3 is a side view of FIG. 1;

FIG. 4 is a front view showing another embodiment of the heat sink according to the present invention.

FIG. 5 is a front view showing still another embodiment of the heat sink according to the present invention.

FIG. 6 is a front view showing still another embodiment of the heat sink according to the present invention.

FIG. 7 is a partial perspective view showing an extruded material serving as a material for manufacturing a heat sink according to the present invention.

FIG. 8 is a partial perspective view showing a process of manufacturing the heat sink of the present invention by cutting the extruded material of FIG. 5;

FIG. 9 is a front view showing the formation of a flat tube for manufacturing the heat sink of the present invention.

FIG. 10 is a partial perspective view of a corrugated plate for manufacturing the heat sink of the present invention.

FIG. 11 is a partial perspective view showing a process of manufacturing a heat sink of the present invention by cutting a flat tube having a corrugated plate attached thereto.

FIG. 12 is a partial perspective view showing an example of a conventional heat sink.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Heat sink 2 Flat plate 3 Heat dissipation piece 4 Opening 5 Upper edge 6 Intermediate edge 7 Side edge 8 Shaped material 9 Upper wall 10 Lower wall 11 Partition 12 Protrusion 13 Meandering intermediate edge 14 Flat tube 15 Corrugated plate 16 Extruded material 17 Flat plate 18 Fin

Claims (4)

[Claims] 1. A heat sink, wherein a plurality of heat radiating pieces having a plurality of openings are arranged on a flat plate so that the openings face each other. 2. The heat radiation piece and the flat plate are made of aluminum (including an aluminum alloy; the same applies hereinafter), and the heat radiation piece and the flat plate are integrally formed.
The described heat sink. 3. An aluminum profile having an upper wall portion and a lower wall portion and having a plurality of openings extending in the vertical direction between the upper wall portion and the lower wall portion through a partition wall portion, is extruded. One of the upper wall portion and the lower wall portion of the extruded profile and the partition wall portion are cut by a predetermined width at an interval in the horizontal direction, and the heat radiation pieces having a plurality of openings are formed so that the openings face each other. A method of manufacturing a heat sink, wherein a large number of heat sinks are formed in parallel on a flat plate. 4. A corrugated corrugated corrugated plate is inserted into a flat tube formed by bending a plate material in the longitudinal direction of the flat tube and integrated, and the flat tubes are spaced apart in the horizontal direction. A plurality of heat dissipating pieces, each of which is cut by a predetermined width to form a plurality of openings, are arranged side by side on a flat plate such that the openings face each other.