JPH10104375A - Heat sink and production method for the heat sink - Google Patents

Abstract

PROBLEM TO BE SOLVED: To obtain a heat sink superior in radiation effect by forming an aluminum radiation plate having comb shape fins and a thicker frame and fixing a plurality of the frames in molten aluminum alloy bath embedding in parallel. SOLUTION: A plurality of fins 2 made by grinding metal aluminum plate in equal intervals into long strips are arranged on a thicker frame 3 in equal intervals to make a comb shape radiation plate 1. A plurality of fins 2 of the radiation plate 1 are inserted inside the grooves of fixed metal mold, the frame 3 is positioned to insert in the cavity of the metal mold and then molten aluminum alloy is pressed in the cavity. The molten aluminum alloy is filled in the cavity while sinking the frame 3 and forms a base and heat sink. After cooling and solidifying this, the heat sink is taken out. By this method, heat sinks with various shapes which are superior in strength and heat conductivity can be obtained.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a heat sink and a method for manufacturing the heat sink, which is suitable as a heat radiating member for a personal computer, a semiconductor, or a small motor of a car, a motorcycle, an electric car, etc., is easy to handle, and has excellent heat radiating effects. And a method for easily manufacturing the heat sink.

[0002]

2. Description of the Related Art Conventionally, there has been known a method of integrally manufacturing metal aluminum, an aluminum alloy, or the like by an extrusion method.
A method of integrating a base and a heat sink by casting is known. Further, as for the heat sink, a plate which is cut into a plate and inserted into a base is known.
In the case of a large heat radiating plate having a large area of about m ² is the insert and base part in a mold part of or the heat radiating plate is manufactured integrally with base and the heat sink in die casting manually or automatically There is also known an insert fin method of solidifying by casting (Japanese Patent Application Laid-Open No. 57-193049). Furthermore, 1
It is also known to form a large number of comb-shaped fins arranged in the vertical and horizontal directions by cutting a lump in the vertical and horizontal directions.

[0003]

However, the conventional method of integrally manufacturing the base and the fin by extrusion or casting is as follows.
If the fins are long and there are many fins,
It is difficult to fill the entire fin with metallic aluminum, aluminum alloy melt, or the like due to poor flow of molten metal. In addition, when a fin obtained by cutting a plate-like object is inserted into a base, it takes time and effort to insert the fins one by one, and it takes time to mount the heat sink, which makes mass production of the heat sink practically difficult. Means for cutting comb-shaped fins that are arranged vertically and horizontally from the body have a problem that the spacing between the fins is large, the working time is long, and the heat radiation effect is poor.

As a result of research on the improvement of the above-mentioned conventional heat sink, the present invention is excellent in heat radiation effect, and is used as a heat sink for small parts such as personal computers and semiconductors, and also as a heat radiation member for small motors such as automobiles, motorcycles and electric vehicles. Another object of the present invention is to provide a heat sink and a method for manufacturing the same.

[0005]

According to a first aspect of the present invention, there is provided a heat sink comprising a fin formed in a comb shape and a heat radiating plate made of metal aluminum having a frame thicker than the fin at one end of the fin. In addition, a plurality of the frames are embedded and fixed in parallel in the molten aluminum alloy.

According to a second aspect of the present invention, there is provided a method for manufacturing a heat sink, comprising a fin formed in a comb shape and a comb-shaped radiator plate formed of a metal aluminum plate having a frame at one end of the fin having a thickness larger than the thickness of the fin. A plurality of fins are inserted into a mold, the frame of the heat sink is positioned in a cavity, an aluminum alloy melt is injected into the cavity, and the frame is buried and fixed in the aluminum alloy melt. .

[0007]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS As shown in FIG. 1, a radiator plate 1 according to the present invention has a plurality of strip-shaped fins 2 formed by cutting a metal aluminum plate at equal intervals, and is formed at one end of the fins 2 to be thicker than the fins. A plurality of fins 2 are arranged at equal intervals on the frame 3 and formed in a comb shape. However, the comb-shaped portion is not limited to this. If necessary, as shown in FIG. 2, even if small cylinders S are arranged at equal intervals on a frame as shown in FIG. 2, or as shown in FIG. The fin 2 may have a fenestration M formed therein.
The connecting portion between the fin 2 and the frame 3 of the heat sink 1 is such that one end of the fin 2 forms a tapered portion D and the other end of the tapered portion D is connected to the frame 3 as shown in FIG. As shown in FIG. 5, the fin 2 may be connected to the frame 3 via the tapered portion D.

Further, as will be described later, the shape of the frame does not necessarily have to be linear, but the frame may be appropriately formed into a curved shape in accordance with the purpose of use, the place of use, etc. The frame should be arranged in the normal direction, the frame should be parallel to the axis of the cylindrical base, and the fins should be arranged in the radial direction, or the fins of multiple parallel heat sinks should be arranged alternately Etc. can be arbitrarily set.

In other words, according to the first aspect of the present invention, since the frame of the heat sink is buried and fixed in the aluminum alloy melt serving as the base, the frame can serve as an anchor. There is no danger of falling off or falling off the device. In addition, the aluminum alloy used for the base must be one that can be joined and integrated with the frame of the heat sink, has high thermal conductivity and strength, and has good castability and is hard to corrode. It is necessary to use Si 6-7
% And an aluminum alloy for casting containing as little impurities as possible such as Cu is desirable.

FIGS. 6 to 8 show a mold for manufacturing the present invention. Next, the manufacturing method of the present invention will be described with reference to the drawings. In a mold composed of a fixed mold A and a movable mold B, a nest 4 is attached inside the fixed mold A and an nest 5 is attached inside the movable mold B. A plurality of spaces 6 into which a plurality of fins can be inserted in parallel are formed in the insert 4, and a cavity 7 into which a molten aluminum alloy can be injected is formed inside the insert 5. I have.
In addition, reference numeral 8 in FIG.
Is a piston, 10 is an overflow gutter, 11 is an extrusion pin, and 12 is an extrusion plate.

In FIG. 6, fins 2 of a plurality of radiating plates 1 formed in advance are inserted into nests 4 of a fixed die A, and a frame 3 of the radiating plate 1 is assembled with dies A and B. It is located in the cavity 7 when it is set. After inserting the fins 2 into the insert 4 and inserting the plurality of heat sinks 1 into the mold as described above, the insert 4 of the fixed mold A and the insert 5 of the movable mold B are assembled. Injection port 8 for molten aluminum alloy
And press-fit into the cavity 7 with the piston 9. still,
6 to 8, the insert 1 is attached to the fixed mold A and the insert 2 is attached to the moving mold B. However, the present invention is not limited to this. Alternatively, the insert 1 may be attached to the movable mold B.

The molten aluminum alloy injected into the cavity 7 is filled into the cavity 7 while burying the frames 3 of the plurality of heat sinks 1 inserted in the mold, forming the base 13 and forming a heat sink. The heat sink may be manufactured after cooling and solidification of the molten aluminum alloy.

That is, according to the method of the present invention, since the fins 2 of the heat sink 1 are connected and fixed by the frame 3, the fins 2 can be easily inserted into the mold with the frame 3,
Next, the molten aluminum alloy is injected into the mold to form the base 1.
3 to manufacture a heat sink.
The operation is simple and can be manufactured in a short time. For example, the injection of a molten aluminum alloy may be performed, for example, by adding 0.1 μm.
Injection can be performed at a high speed of 5 m / sec.
0 to 200 kg / cm ^2, which is suitable for mass production of heat sinks.

In the structure of the fins 2 and the frame 3 shown in FIG. 1, the radiating plate 1 is provided between the wall of the insert 4 space and the fins 2 and the frame 3 and the connection between the fins 2 and the frame 3. There is a possibility that the molten aluminum alloy may leak to the fin 2 side, and the molten aluminum alloy may not easily adhere to the fin 2 and the frame 3. Therefore, the taper shown in FIG. 4 or FIG. It is desirable to use a heat sink having a portion D and press-fit the fins 2 into the nest 4 space portion 3 so as to prevent the generation of minute gaps.

The fins 2 formed on the heat sink 1
Is caused by the flow of molten metal when the radiator plate 1 and the base 13 are integrally manufactured by a casting method as in the related art, because the metal aluminum plate is previously formed in a comb-like shape having an arbitrary size, shape, and number. The occurrence of defective fins can be largely eliminated.

FIG. 9 shows an example of a heat sink obtained by the method of the present invention.
.., 1 g are arranged in parallel with the base 13, and the frame of each heat sink 1 is embedded and fixed in the base 13. In this case, the heat sinks 1a, 1b,.
Since the interval b between the fins 2 and the length c of each fin 2 in each heat sink 1 can be formed to predetermined dimensions and sizes, they can be used as heat sinks for various computers.

Furthermore, by appropriately changing the shape of the cavity in the mold and the shape of the nest of the mold, heat sinks of various shapes can be manufactured simply and reliably. That is, FIG. 10 shows a case in which the fins 2 of the plurality of heat sinks 1 are arranged in the normal direction to the base 13 formed into a curved surface.
1 is a heat sink in which the fins 2 are arranged in the radial direction in parallel with the axis of the base 13 on which the heat sink 1 is formed in a cylindrical shape.
2, a heat radiating plate 1 having a long fin 2 is arranged at the center of the base 13, and a heat radiating plate 1 having a short fin 2 is gradually arranged toward both ends, and the tip of the fin 2 swells at the center of the base 13. The shape of the heat sink is respectively shown.

FIG. 13 shows a heat sink having a shape in which the tip of the fin 2 of the heat sink 1 draws a sine curve. In addition, a heat sink in which the substrate 13 has an arbitrary shape such as a rectangular shape, a triangular shape, and an elliptical shape. Therefore, a heat radiation member suitable not only as a heat sink for a personal computer and a semiconductor but also as a heat radiation member for a small motor such as an automobile, a motorcycle, and an electric vehicle can be easily provided.

Further, in the present invention, since the metal aluminum as the material of the heat sink and the aluminum alloy of the cast alloy serving as the base are the same aluminum-based metal, the heat sink 1 and the base 13 are well adapted to each other. Since the frame 3 of each heat radiating plate 1 is formed thicker than the thickness of each fin 2, the frame 3 is embedded in the base 13 in an anchor shape, so that the heat radiating plate 1 falls off the base 13 or falls off. There is no danger at all. The surface of the frame 2 of the heat sink 1 may be melted by contact with the molten aluminum alloy, and may be melted and integrated with the molten aluminum alloy.

[0020]

As described above, in the heat sink of the present invention, since the frame of the heat sink is embedded and fixed in an anchor shape in the base, there is no possibility that the heat sink falls off or falls off the base, and the heat sink is excellent in strength. In addition, the thermal conductivity is good. In addition, since the fins of the heat sink are formed in a desired shape in advance, the size and number of the fins can be appropriately selected as necessary, so that heat sinks of various shapes or small motors such as automobiles and motorcycles can be used. A heat sink for use.

Further, according to the method of the present invention, a frame having a thickness larger than the thickness of the fins of the heat radiating plate is formed on a heat radiating plate formed in a predetermined shape in advance, and a plurality of heat radiating plates are inserted into a mold. Is located in the cavity, and the molten aluminum alloy is injected into the cavity to bury the frame of the radiator plate in the molten aluminum alloy. In addition, the operation is simple and the processing can be performed in a short time, so that mass production can be achieved.

[Brief description of the drawings]

FIG. 1 is a perspective view of an example of a heat sink.

FIG. 2 is a perspective view of another example of a heat sink.

FIG. 3 is a partial front view of still another example of the heat sink.

FIG. 4 is a cross-sectional view of an example of a heat sink.

FIG. 5 is a sectional view of another example of a heat sink.

FIG. 6 is a longitudinal sectional view of an example of a mold used in the manufacturing method.

FIG. 7 is a plan view of a fixed mold of the same mold.

FIG. 8 is a plan view of a movable mold of the same mold.

FIG. 9 is a perspective view of an example of a heat sink according to the present invention.

FIG. 10 is a schematic side view of a heat sink having a base formed in a curved shape.

FIG. 11 is a schematic side view of a heat sink in which a base is formed in a cylindrical shape.

FIG. 12 is a schematic side view of another example of the heat sink.

FIG. 13 is a schematic side view of still another example of the heat sink.

[Explanation of symbols]

 1: heat radiating plate 2: fin 3: frame 4, 5: insert 6: space 7: cavity 8: injection port of molten aluminum alloy 9: piston 10: overflow gutter 11: extrusion pin 12: extrusion plate 13: base A : Fixed die B: Moving die D: Taper part M: Window part of fin S: Small cylindrical body

Claims (4)

[Claims] 1. A fin formed in a comb-like shape, and a radiator plate made of metal aluminum having a frame thicker than the fin at one end of the fin is formed. A heat sink, wherein a plurality of heat sinks are embedded and fixed in parallel. 2. The heat sink according to claim 1, wherein the lower part of the fin of the radiator plate is connected to the frame via a tapered portion that is gradually thickened. 3. A plurality of comb-shaped fins made of metal aluminum having a comb-teeth shape and a heat-dissipation plate made of metal aluminum having a frame thicker than the fin at one end of the fin. A method of manufacturing a heat sink, comprising: positioning a frame of the heat sink in a cavity; injecting a molten aluminum alloy into the cavity; and burying and fixing the frame in the molten aluminum alloy. 4. The method for manufacturing a heat sink according to claim 3, wherein the tapered portion of the heat sink according to claim 2 is press-fitted into an opening end of a nest space portion of a mold.