JPH10319156A - Method and device for manufacturing heat sink - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a method and a device for manufacturing a heat sink with a narrow pitch between fin bodies easily and positively. SOLUTION: A plurality of fin bodies 12 are pinched among a plurality of spacers 13, one edge part of the fin bodies 12 is allowed to project from each spacer 13, and the fin body 12 and the spacer 13 are adhered each other. The edge part of the projecting fin body 12 is accommodated in a cavity 22, at the same time a molten metal 23 that is a material for forming a base at the cavity 22 is injected, and the edge part of each fin body 12 is packed by the molten metal 23 to solidify it, thus assembling the base and each fin body 12 in one piece.

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 increasing a heat exchange area in various types of heat exchange equipment and heat transfer devices.

[0002]

2. Description of the Related Art In heat-related equipment such as heat pipes,
It is well known that a heat sink is provided to increase the heat exchange area by increasing the heat radiation area or heat absorption area.

FIG. 8 and FIG. 9 show an example thereof. The heat sink 1 shown in FIG. 8 has a configuration in which a plurality of flat fin bodies 2 parallel to each other are provided in an upright state on the upper surface of a flat base 3, and is extruded using, for example, an aluminum alloy as a material. It is manufactured by a molding method. FIG.
Has a configuration in which the fin body 2 is formed in a cylindrical shape by replacing the fin body 2 with a flat plate shape, and is manufactured by, for example, forging using a copper alloy as a material.

Here, the above-mentioned extrusion or forging is a method of integrally processing the fin main body 2 and the base 3 from a single material. Therefore, as shown in FIG. The fin body 2 to be obtained has a minimum thickness (t) of about 2 mm and a thickness (t) of 2 mm.
The height (h) of the fin main body 2 when the height is set to 20 mm is limited to about 20 mm at the maximum. Therefore, the ratio (C) between the thickness (t) and the height (h) of the fin body 2 in these manufacturing methods is expressed as C = h / t ≦ 20/2 = 10. Further, the pitch (p) between the fin bodies 2 is required to be at least 5 mm or more.

As described above, in the conventional heat sink 1 obtained by the manufacturing method by extrusion molding or forging, the fin body 2 cannot be formed thin and high, and the fin body provided with respect to the surface area of the base 3 is not provided. 2
Because the number (number) of is small, there is a disadvantage that the heat exchange area is restricted.

Therefore, as a means for solving the above problems, a heat sink employing a pressure casting method has been proposed, and this will be briefly described with reference to FIGS. 11 and 12. FIG. A linear holding groove 5 is provided on the bottom surface of the upper mold 4 (movable mold).
Are formed in parallel with each other, and these holding grooves 5 are formed, for example, with aluminum (A).
The upper ends of the fin bodies 6 each made of a rolled sheet made of l) are held in a fitted state. The lower end of each fin body 6 protrudes about 1 to 2 mm into the lower mold 7, and this dimension is
Insertion depth.

On the other hand, the bottom surface of the lower die 7 (fixed die) is formed as a flat surface. The lower die 7 is provided with a pressurizing plunger 10 configured to press the molten metal 9 of Cu, which is the material of the base 8, upward from below. Then, when the pressure plunger 10 is moved toward the upper mold 4 from the above state and pressure is applied to the molten metal 9, about 1 to 2 mm of the lower end of each fin body 6 is covered with the molten metal 9. Then, after the molten metal 9 is solidified, if a washing step or the like is performed as usual, the heat sink 11 having the configuration shown in FIG. 13 is completed.

According to this kind of manufacturing method by pressure casting, a ready-made rolled plate is adopted as the fin body 6, so that both the thinness and the height of the fin body 6 are more compatible than the manufacturing method by forging or extrusion. In addition to being possible, the pitch of each fin body 6 can be set narrow. As a result, the heat exchange area of the heat sink 11 can be made larger than that of the above-described conventional heat sink.

[0009]

In the above pressure casting method, the number of the fin bodies 6 and the pitch between the fin bodies 6 are determined by the holding grooves 5 formed in the upper die 4.
Is determined in accordance with the interval. Therefore, when manufacturing a plurality of types of heat sinks having different numbers of fins 6 or different pitches, it is necessary to prepare an upper die corresponding to each heat sink, and therefore, there has been an inconvenience of increasing the manufacturing cost. Further, even if the interval between the holding grooves 5 is formed as narrow as possible, there is a limit in the processing accuracy.
It was difficult to manufacture a heat sink 11 having a pitch of 2 mm or less.

Further, in the above-mentioned pressure casting method, the fin body 6 is merely fitted tightly into the holding groove 5, and the fin body 6 is caused by a difference in the coefficient of thermal expansion between the upper mold 4 itself and the rolled plate itself. There is a possibility that a small gap may be formed between the two, and the molten metal may enter there. In such a case, not only the expected product is not obtained, but in an extreme case, the upper mold may be damaged. was there.

The present invention has been made in view of the above circumstances, and provides a method and an apparatus for manufacturing a heat sink capable of easily and reliably manufacturing a heat sink having a narrow pitch between fin bodies.

[0012]

Means for Solving the Problems and Action Therefor To achieve the above object, the invention described in claim 1 comprises a plurality of fin bodies sandwiched between a plurality of spacers, respectively. The fin body and the spacer are brought into close contact with each other with one end protruding from each spacer, the end of the protruded fin body is accommodated in the cavity, and the base material is formed in the cavity. The method is characterized in that the molten metal is poured, the ends of the fin bodies are wrapped with the molten metal, and the molten metal is solidified, whereby the base and the fin bodies are integrally assembled.

According to the first aspect of the present invention, the pitch between the fin bodies can be arbitrarily set according to the thickness or thickness of the spacer itself or the number of the spacers. Can be manufactured.

According to a second aspect of the present invention, while holding one end of each of the plurality of fin bodies, the other end of each of the fin bodies is wrapped with a molten metal as a material of the base. In a heat sink manufacturing apparatus for manufacturing a heat sink in which the fin body is provided in an upright state, a plurality of fin bodies are alternately arranged with a plurality of spacers, and the other end of the fin body protrudes from the spacer. In this state, the other end portion of the fin body tightened with the spacer interposed is housed in a liquid-tight state, and the molten metal is injected under pressure. And a casting mold.

Therefore, according to the second aspect of the present invention, the fin main body and the spacer are housed in the casting mold alternately with each other and in a state where they are integrally fastened. Then, when the molten metal is solidified while pressure is poured into the casting mold, the protruding end of each fin body is cast-molded. That is, a heat sink having a configuration in which a plurality of fin bodies are provided upright on the surface of the base is completed.

In this case, there is no gap between the edge of each fin body and the casting mold and between the edge of each spacer and the casting mold. Since there is no gap between them, burrs and the like do not occur on the surface of the solidified molten metal, that is, the intended heat sink can be easily and reliably manufactured.

Further, in manufacturing a plurality of types of heat sinks having different pitches, the apparatus can be shared, so that the manufacturing cost can be reduced as compared with the related art.

Further, according to a third aspect of the present invention, in the heat sink manufacturing apparatus according to the second aspect, each of the spacers is engaged with the casting mold in a direction intersecting with a tightening direction of the tightening means. It is characterized in that an engaging means for combining and integrating is provided.

Therefore, according to the third aspect of the present invention, the state in which the respective fin bodies are integrally assembled by the molten metal,
If the fin body and the casting mold are separated from each other in the surface direction of the fin body, the movement of each spacer in the direction away from the casting mold is prevented by the engagement means, so that only each spacer remains in the casting mold. That is, the plurality of spacers can be removed from the fin body at a time, and therefore, the manufacture of the heat sink is further simplified as compared with the second aspect of the present invention.

[0020]

Next, an embodiment of the present invention will be described with reference to the drawings. FIG. 1 is a view showing a fin main body. The fin main body 12 is, for example, a rectangular flat plate made of aluminum (Al) or an Al alloy. FIG. 2 is a schematic view showing the spacer 13. The spacer 13 shown here is, for example, a flat plate made of Al or an Al alloy, and has the same width as the fin body 12. In addition, engagement protrusions 14 protruding in the width direction from a substantially central position in the height direction are formed at the left and right edges of the spacer 13 in FIG. These engaging projections 14 have a rectangular shape.

FIG. 3 is a schematic view showing the casting mold 15. The casting mold 15 shown here includes, as an example, a bottom portion 16 that forms a flat surface, an engaging wall portion 17 that rises vertically from the left and right edges of the bottom portion 16 in FIG. And a wall 18 which is connected to the inner edge of the engaging wall 17 and rises vertically from the bottom. The wall 18 has a flat surface.

On the surfaces of the respective engaging walls 17 which face each other, there are formed engaging grooves 19 which are directed horizontally to the surface of the bottom 16 in the depth direction in FIG. These engagement grooves 19 are linear grooves formed by recessing the surface of the engagement wall 17 into a rectangular shape. Therefore,
The engagement groove 19 and the engagement protrusion 14 correspond to the engagement means of the third aspect of the present invention. The heights of the engaging wall portions 17 and the wall portions 18 are the same, and the interval between the engaging wall portions 17 is the same as the width dimension of the fin body 12.

Therefore, the surface of the engaging wall 17 and the bottom 1
The projection shape of the surface 8 in the direction of the groove 18 is the spacer 1
3 corresponds to the projected shape in the thickness direction. The projection shape of the upper portion of the engagement wall portion 17 in the direction of the groove portion 18 in FIG. 3 from the engagement groove portion 19 is the same as the projection shape in the thickness direction of the fin body 12 in the state shown in FIG. Match.

Here, a procedure for attaching the fin body 12 and the spacer 13 having the above-described configuration to the casting mold 15 will be described. First, the engaging projection 14 of the spacer 13 is fitted into the engaging groove 19 of the casting mold 15 and is slid until it comes into contact with the wall 18, and then the fin body 12 is brought into surface contact with the spacer 13. It is arranged between the engaging walls 17. Thereafter, the required number of fin bodies 12 and spacers 13 are alternately attached in the same manner as described above (see FIG. 4).

In this case, the upper edge of each spacer 13 is flush with the upper edges of the engaging wall 17 and the wall 18. On the other hand, the upper edge of each fin body 12 slightly protrudes from the upper edges of the engaging wall portion 17 and the wall portion 18, and this dimension is determined by the insertion depth of the fin body 12 with respect to the base described later. become.

Further, the outer surface of the wall 18 of the casting mold 15 and the side surface of the spacer 13 are clamped by the clamper 20. As a result, each fin body 12 and each spacer 13 are tightened in the thickness direction, and the three members are integrally fixed. Therefore, the clamper 20 corresponds to the fastening means according to the second aspect of the present invention.

Next, the fin body 12 is assembled with the base 5. The casting mold 15 to which the plurality of fin bodies 12 and the spacers 13 are attached as described above is
In the cavity 22. More specifically, the casting mold 15 is held in a state where the end face of each spacer 13 faces in parallel to the bottom face of the cavity 22 forming a flat surface. The distance between the end surface of the spacer 13 and the bottom surface of the cavity 22 corresponds to the thickness of the base 25. Further, copper (Cu), which is a material of the base 25, is
5 is provided with a pressure plunger 24 configured to press the melt 23 upward from below in FIG.

From the above state, as shown in FIG. 6, the pressure plunger 24 is moved in the direction of the arrow toward the casting mold 15 to apply pressure to the molten metal 13. Then, the protruding lower end of each fin body 12 and each spacer 1
3 is covered with the molten metal 23. Fin body 12
When the lower end portion contacts the molten metal 23 of Cu, the surface of the fin body 12 is melted because the melting point of Al is lower than the melting point of Cu. Then, when the material of the molten metal 23 and the material of the fin main body 12 are solidified together, the plurality of fin main bodies 12 are cast-in by the base 25 and both are integrally connected.

In this case, since a clamping force in the thickness direction of the fin body 12 is exerted by the clamper 20,
Even if there is a difference in the coefficient of thermal expansion between the fin body 12 and the spacer 13, the molten metal 24 does not enter between the spacer 13 and the fin body 12 and between the spacer 13 and the wall 18. Since the edge of the spacer 13 is in close contact with the surface of the engagement wall portion 17 of the casting mold 15, the molten metal 24 enters between the casting mold 15 and the edge of the spacer 13 and the edge of the fin body 12. do not do.

Next, from the casting mold 15 to the heat sink 2
Take out the finished product of 6. That is, after the members such as the casting mold 15 and the base 25 are sufficiently cooled, the clamper 20
Is removed, and the base 25 and the casting mold 15 are separated from each other in the surface direction of the fin body 12. As described above, each of the spacers 1 is provided in the engagement groove 19 of the casting mold 15.
Since the engaging projections 14 are locked, and the spacer 13 is prevented from moving in the above-described direction, the base 25 and the fin body 12 that are integrally assembled are taken out of the casting mold 15. , Each spacer 13 is a casting mold 1
Remains within 5. Thus, the plurality of fin bodies 12 and the spacers 13 arranged alternately can be separated by one operation.

Further, if the heat sink 26 taken out of the casting mold 15 is washed and inspected according to the usual manner, a series of manufacturing operations is completed, the pitch between the fin bodies 12 is narrower than before, and the base 25 has a smaller pitch. The heat sink 26 having no burrs on the surface can be obtained. As shown in FIG. 7, the heat sink 26 is provided on a top surface of a flat plate-shaped Cu base 24 with a plurality of Al
The fin body 12 is provided with a narrow pitch.

As described above, according to the above-described specific example, the pitch of the fin body 12 can be arbitrarily set using the spacer 13 made of an existing rolled plate.
By preventing the infiltration of the molten metal 23 between the fin body 12 and the fin body 12 and between the fin body 12 and the casting mold 15, the heat sink 26 having a narrower pitch than in the related art can be easily and reliably manufactured. Furthermore, since a plurality of types of heat sinks 26 having different pitches can be manufactured using the same casting mold 15, the manufacturing cost as a whole can be reduced.

In the above-described specific example, the flat fin body 12 is exemplified. However, the present invention is not limited to the above-described specific example. Or it may be prismatic. Note that the fin body 12 and the reinforcing plate are not limited to rolled materials, and those formed by cutting or those formed by casting can be adopted. Further, the material of the fin body 12 and the base 25 is C
Although u and Al have been exemplified, the invention is not limited thereto, and for example, graphite, magnesium, or the like may be employed.

[0034]

As is apparent from the above description, according to the manufacturing method of claim 1, a plurality of fin bodies are sandwiched between a plurality of spacers, and one end of each fin body is separated from each spacer. The fin body and the spacer are brought into close contact with each other in a state where the fin body is also protruded, and the end of the protruded fin body is accommodated in the cavity, and the molten metal of the material forming the base is injected, and each fin body is The ends of the fins are wrapped in a molten metal, and the molten metal is solidified to assemble the base and each fin body together, so that the pitch between the fin bodies can be set arbitrarily by the spacer. Can be easily and reliably manufactured.

According to the manufacturing apparatus of the present invention, the plurality of spacers alternately arranged with the plurality of fin bodies and the fin body with the other end of the fin body protruding from the spacers. And a casting means in which the other end of the fin body tightened with the spacer interposed is housed in a liquid-tight state and the molten metal is injected under pressure. Thus, a heat sink having a narrow pitch between the fin bodies can be easily and reliably manufactured. Further, in manufacturing a plurality of types of heat sinks having different pitches, the apparatus can be shared, so that the manufacturing cost as a whole can be reduced.

Further, as described in the third aspect, by providing engaging means for engaging the respective spacers with the casting mold in a direction intersecting with the tightening direction of the tightening means to provide an integral unit, Can be separated at a time from the spacers and the fin body
This has the advantage that the manufacture of the heat sink is simpler.

[Brief description of the drawings]

FIG. 1 is a schematic view showing a fin body.

FIG. 2 is a schematic view showing a spacer.

FIG. 3 is a schematic view showing a casting mold.

FIG. 4 is a schematic view showing a state in which a fin body and a spacer are attached to a casting mold.

FIG. 5 is a schematic view showing a state where a casting mold is housed in a cavity.

FIG. 6 is a schematic view showing a pressure casting step.

FIG. 7 is a schematic view showing a completed heat sink.

FIG. 8 is a schematic view showing an example of a conventional heat sink.

FIG. 9 is a schematic view showing another example of a conventional heat sink.

FIG. 10 is a schematic diagram showing the relationship between the thickness and height of a fin body in a conventional heat sink.

FIG. 11 is a schematic diagram showing a state before pressing in a conventional example employing a pressure casting method.

FIG. 12 is a schematic diagram showing a state during pressurization in the manufacturing method.

FIG. 13 is a sectional view showing a heat sink manufactured by a pressure casting method.

[Explanation of symbols]

12: Fin body, 13: Spacer, 14: Engagement projection, 15: Cast-in mold, 19: Engagement groove, 20
... Clamper, 22 ... Cavity, 23 ... Molten metal, 2
5: Base, 26: Heat sink.

Continuation of front page (72) Inventor Yoshihiro Nagaki 1-5-1, Kiba, Koto-ku, Tokyo Inside Fujikura Co., Ltd.

Claims (3)

[Claims] A plurality of fin bodies are sandwiched between a plurality of spacers, and the fin bodies and the spacers are brought into close contact with each other with one end of each fin body protruding from each spacer. The protruding end of the fin body is accommodated in the cavity, and the molten metal of the base forming material is injected into the cavity, and the end of each fin body is wrapped with the molten metal, and the molten metal is further solidified. A method of manufacturing a heat sink, wherein the base and each fin body are integrally assembled. 2. The fin body is provided upright on the surface of the base by wrapping the other end of the plurality of fin bodies in a molten state as a material of the base while holding one end of the plurality of fin bodies. A heat sink manufacturing apparatus for manufacturing a heat sink, comprising: a plurality of fin bodies and a plurality of spacers alternately arranged; and a state in which the other end of the fin body is projected from the spacer. And a casting mold in which the other end of the fin body tightened with the spacer interposed is housed in a liquid-tight state and the molten metal is injected under pressure. An apparatus for manufacturing a heat sink. 3. An engaging means for engaging each of said spacers with said casting mold in a direction intersecting with a tightening direction of said tightening means, respectively, is provided. 3. The apparatus for manufacturing a heat sink according to claim 2.