JPH09138091A - Radiating plate - Google Patents

Abstract

PROBLEM TO BE SOLVED: To improve the radiating effect of a low-cost heat sink by providing a plurality of radiating pins on the one surface of a base plate and forming the pins in the sections into a star shape. SOLUTION: Many radiating pins 3 are provided on the one surface of a base plate 2. The pins 3 exhibit substantially star-shaped section with protrusions 3A provided at each five positions of the peripheries, thereby forming larger surface areas as compared with prior art. An intermediate radiating pin 4 is provided substantially at the center of the heat sink 1 in such a manner that the pin 4 is formed thicker than the pin 3 to increase the surface area by providing a recess 4C of predetermined shape at the end and providing a plurality of the protrusions 3A on the peripheries. Thus, the radiating effect of the heat sink can be improved. Accordingly, if it is mounted at an IC for generating a large quantity of heat, the rise of the temperature of the IC due to the natural radiation can be prevented.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a heat radiating plate suitable for a heating element such as a semiconductor, especially for an integrated circuit equipped with a semiconductor that generates a large amount of heat.

[0002]

2. Description of the Related Art In recent years, there have been increasing numbers of ICs having microminiature electronic circuits in which elements including a large number of semiconductors and internal wiring are combined as a single solid by a special method. In particular, ICs having a small shape and capable of high-speed arithmetic processing have been developed and used, and many of these ICs generate a large amount of heat in the process of operation. When such a semiconductor is operated, there is a problem that the operation of the semiconductor itself becomes unstable due to the generated heat, and the semiconductor is destroyed when the temperature of the semiconductor rises.

Therefore, a heat sink for cooling the semiconductor is used as an IC.
The heat of the IC is transferred to the heat dissipation plate, the heat of the heat dissipation plate and the air are exchanged, and the heat of the semiconductor is released into the air. This prevents instability or destruction of the semiconductor due to temperature rise. As is well known, the larger the contact area between the heat sink and the air, the larger the heat exchange area between the heat sink and the air, and the higher the heat exchange rate.

That is, the larger the surface area of the heat radiating plate, the more the heat of the IC can be radiated into the air. Therefore, heat sinks such as ICs that have semiconductors that have large shapes such as power transistors and rectifiers that generate a large amount of heat have been thin plate-shaped with a predetermined interval on one surface of a base plate that has been conventionally made of metal such as aluminum. There are many fins. By providing a large number of thin plate fins, the contact area between the heat dissipation plate and the air is increased, and the heat dissipation efficiency of the heat dissipation plate is improved. In this case, the heat sink is mainly formed by die casting, aluminum extrusion (press molding), and cutting.

In addition, the heat sink of the IC, which is small in size and performs high-speed arithmetic processing, is provided with a large number of thin round pillars or prismatic heat dissipation pins arranged in a grid pattern instead of the thin plate fins. The contact area with is further improved to obtain greater heat dissipation efficiency. Since the heat dissipation pin of this heat dissipation plate is thin and the number is large, the surface area of the heat dissipation plate can be increased,
For example, a large number of heat dissipation pins are formed on one surface of the base plate by cutting a square of about 1 mm to 2 mm with a length of about 10 mm, or by drilling a hole on one surface of the base plate and implanting a thin long columnar heat dissipation pin. Is forming.

In this case, the heat radiation plate is cut with a milling machine or the like to provide a large number of square heat radiation pins in each row in the vertical and horizontal directions, which takes a lot of time and labor for cutting. In addition, when cutting a heat dissipation pin to process a long and narrow heat dissipation pin, the heat dissipation pin may be bent or chipped from the middle during cutting, making it difficult to process a thin and long prismatic heat dissipation pin, and it takes a lot of time. However, there was a cost increase.

For this reason, in recent years, as described below, a method has been developed in which elongated heat dissipation pins can be easily formed with a simpler structure. In other words, in this case, make a casting mold with many round holes that form thin and long radiating pins,
The heat-melted aluminum material is poured into this casting die to integrally form the base plate and the plurality of heat-radiating pins to manufacture a heat-radiating plate. As a result, a plurality of thin and long heat dissipation pins are formed on one surface of the base plate.

[0008]

However, when the heat dissipation plate is machined, the shape of the heat dissipation pin is generally rectangular in cross section, and the cross section of the heat dissipation pin in the casting die is generally round. It was The surface area of the heat dissipation plate is determined by the thickness and number of the heat dissipation pins. If the heat dissipation pin is thick, the strength of the heat dissipation pin increases, but the surface area of the heat dissipation plate decreases. If the heat dissipation pin is thin, the surface area of the heat dissipation plate can be increased, but the strength is weakened and the heat dissipation pin is damaged. Therefore, there has been a demand for the development of a heat radiating plate which is not damaged and is inexpensive and has improved heat radiation efficiency.

The present invention has been made to solve the problems of the prior art, and an object of the present invention is to improve the heat dissipation efficiency of the heat sink and to provide an inexpensive heat sink.

[0010]

That is, the heat radiating plate 1 of the invention of claim 1 has a plurality of heat radiating pins 3 ...
In the heat dissipation plate provided with, the cross section of the heat dissipation pins 3 ... Has a star shape.

According to a second aspect of the present invention, there is provided a heat radiating plate 1 having a plurality of heat radiating pins 3 ... 3A
... is provided.

According to the third aspect of the present invention, there is provided a heat dissipation plate 1 having a plurality of heat dissipation pins 3 ... Provided on one surface of a base plate 2. The fins 3B are provided.

A heat sink plate 1 according to a fourth aspect of the present invention is the heat sink plate according to the first, second or third aspect, wherein a recess 3C is provided at the tip of the heat sink pin 3.

Furthermore, the heat dissipation plate 1 of the invention of claim 5 is the heat dissipation plate according to claim 1, claim 2, claim 3 or claim 4, which is formed by casting an aluminum material.

Furthermore, the heat dissipation plate 1 of the invention of claim 6 is
In the above-mentioned claim 1, claim 2, claim 3 or claim 4, the heat dissipation plate 1 is formed by press molding an aluminum material.

[0016]

Next, an embodiment of the present invention will be described in detail with reference to the drawings. FIG. 1 is a front view of a heat sink 1 of the present invention, and FIG.
Is a side view of the heat dissipation plate 1 of the present invention, FIG. 3 is a front view of the heat dissipation pin 3 of the present invention, FIG. 4 is a side view of the heat dissipation pin 3 of the present invention, and FIG.
Shows cross-sectional views of the die-cast molding die 10 of the heat dissipation plate 1 of the present invention, respectively. For example, the heat radiating plate 1 radiates heat generated from a semiconductor having an integrated circuit such as an IC into the air to cool the semiconductor, and a large number of base plates 2 are arranged on one surface of the base plate 2 at a predetermined interval. It is composed of heat dissipation pins 3 ...

The heat radiating plate 1 fixes the base plate 2 to an IC (not shown), transfers the heat of the semiconductor to the heat radiating pins 3, and radiates the heat into the air from the heat radiating pins 3, and is made of an aluminum material having a high thermal conductivity and a light weight. It is made of metal. A large number of heat dissipation pins 3 to be described later are provided on one surface of the base plate 2, and the other surface of the base plate 2 is configured to be in close contact with the surface of an IC or the like for easy attachment. Further, the base plate 2 is provided with a mounting hole (not shown when mounting with an adhesive) (not shown) for mounting and fixing to an IC or the like at a predetermined position.

On the other hand, the heat radiating pins 3 are provided on the one surface of the base plate 2 at a predetermined interval so as to project in a grid pattern (FIGS. 1 and 12) or a staggered pattern (FIG. 10).
Is about 8.5 mm long and the tip size is about 1.5 m
m, the size of the base plate 2 side is about 2.5 mm, and a slope with a thinner tip than the base plate 2 side is provided. By providing this gradient, the heat dissipation pin 3 is formed so as to be easily released from the mold during molding.

The heat dissipating pin 3 has five protrusions 3 around it.
A has a substantially star-shaped cross section, and has a very large surface area with respect to a conventional heat dissipation pin having a substantially circular column or prism. Further, a middle heat radiating pin 4 is provided at a substantially central portion of the heat radiating plate 1 (FIG. 1). The middle heat radiating pin 4 is formed thicker than the heat radiating pin 3 and has a recess 4C having a predetermined shape at its tip. Along with the provision of multiple protrusions 3A
・ ・ Is provided. The middle heat dissipation pin 4 also has an extremely large surface area due to the plurality of protrusions 3A provided around the middle heat dissipation pin 4.

Further, between the heat radiating pins 3 of the heat radiating plate 1 (FIGS. 10 and 12), the heat radiating pins 3 are located from the base plate 2 side.
... Slightly protruding to the side (length about 3 mm, diameter 2.5 mm)
The contact pins 5 ... Are provided. This contact pin 5
.. is a portion where an extruding pin of a die (not shown) for releasing the heat radiating plate 1 from the die after molding comes into contact. In this case, the base plate 2 may be directly pressed by the push-out pin of the mold without providing the contact pins 5 ...

Next, the manufacturing procedure of the heat sink 1 will be described with reference to FIG. The die casting mold 10 is a cavity side mold 10A.
And a core-side mold 10B, the core-side mold 10
A mold 11 for the heat dissipation plate 1 is attached to B. The heat radiating plate 1 is formed in the mold 11 of the heat radiating plate 1.
3 and a vacuum chamber 12 are provided.
The tip of the radiation pin molding portion 13 communicates with the vacuum chamber 12, and the vacuum chamber 12 is provided with a breathable material (not shown).

The breathable material is made of a material that allows air to easily pass therethrough, while the molding material (aluminum or the like) for the heat dissipation plate 1 does not easily pass therethrough. A pipe 14 is connected to one side of the vacuum chamber 12, and a vacuum pump (not shown) is connected to the pipe 14 via a limit switch (not shown). A pipe 15 is connected to the other side of the vacuum chamber 12, and a compressed air discharge device (not shown) is also connected to the pipe 15 via a limit switch (not shown).

When molding the heat dissipation plate 1, first, the molding die 11 of the heat dissipation plate 1 is heated to a temperature at which it can be molded by a heater (not shown). Next, a mold release material (spray oil or the like) (not shown) for easily taking out the heat sink 1 is applied to the molding die 11 of the heat sink 1, and the molds (cavity side die 10A and core side die 10B) are attached. close. Then, while closing the limit switch of the pipe 15 connected to the other side of the vacuum chamber 12,
The limit switch of the pipe 14 connected to one side is opened, and the air is sucked and extracted by the vacuum pump. As a result, the vacuum chamber 12 and the molding die 11 for the heat sink 1 are evacuated.

Next, a material (not shown) (in this case, an aluminum material) melted at + 680 ° C. to + 700 ° C. is filled into the molding die 11 by applying a predetermined pressure using a hydraulic cylinder (not shown). At this time, since the inside of the die 11 is in a vacuum, the molten aluminum material can be easily filled, and the tips of the respective radiating pin forming portions 13 ...
Since it is in communication with 2, the molten aluminum material is filled in each of the radiation pin molding portions 13 ...

As a result, the melted aluminum material easily flows into the tips of the radiation pin molding portions 13 ... Further, the melted aluminum material is blocked by the breathable material provided in the vacuum chamber 12, and does not flow into the vacuum chamber 12 any more. Then, when the filling of the aluminum material is completed, the die casting mold 10 is cooled by a cooling device (not shown).
As a result, the molding die 11, the product (radiation plate 1) in the die 11 and the runner portion are cooled.

The die casting mold 10 is cooled in a state where the aluminum material in the mold 11 is solidified by cooling for a predetermined time.
The cavity side mold 10A and the core side mold 10B are opened, the vacuum pump is stopped, and the limit switch of the one pipe 14 is closed. Next, the limit switch of the other pipe 15 is opened and compressed air is blown into the vacuum chamber 12 for a predetermined time from the compressed air discharge device.

A push-out pin (not shown) is provided between the tip of the middle heat dissipation pin 4 and each heat dissipation pin 3 formed on the base plate 2 of the heat dissipation plate 1 (each contact pin 5 ... In FIGS. 10 and 12). (Ejector pin) Push out the heat sink 1 from the die 11 and take it out. In this case, the push-out pin has a shape matching the recess 4C provided at the tip of the middle heat dissipation pin 4.

Further, when the cavity side mold 10A and the core side mold 10B of the die casting mold 10 are opened, compressed air is blown into the vacuum chamber 12 so that the heat radiating plate 1 can be molded with a large number of molds (11). The radiation pin molding portion 13 ... Or the breathable material etc.) is blown away with dust such as aluminum dust and carbon to prevent the molding die 11 and the breathable material from being clogged with dust. The heat sink 1 and the molding die 11 are cooled. Then, after taking out the heat sink 1 from the molding die 11, deburring formed in a parting part or the like at the time of molding, or I of the base plate 2 is removed.
Predetermined post-processing such as finishing of the mounting surface of C is performed.
As a result, the plurality of heat dissipation pins 3 ... Are integrally formed on the base plate 2 to complete the heat dissipation plate 1.

Since the heat dissipation plate is molded by the die casting mold 10 without using a conventional resin mold, the shape of the heat dissipation pin 3 can be easily made into a star shape without deformation of the mold. Can be molded. Thereby, the heat dissipation plate 1 can be manufactured in an extremely short time, and the production efficiency can be improved.
Moreover, the surface area of the heat dissipation pin 3 can be made large, and the heat dissipation efficiency can be improved.

Next, an example of using the heat sink 1 will be described. First, when fixing the heat radiation plate 1 with an IC attached to an electric circuit (not shown), the IC, the heat radiation plate 1 and the heat radiation plate 1 may be fixed with each other, or the heat radiation plate may be fixed. The other side of the base plate 2 of No. 1 is closely attached, and a screw is inserted into a mounting hole (not shown) and fixed. In this case, the base plate 2 of the heat dissipation plate 1 and the IC are fixed to each other via grease or the like suitable for heat dissipation in order to increase adhesion.

When the IC (semiconductor) is operated in this state, the IC gradually generates heat and its temperature rises. However, since the radiator plate 1 is closely attached to the IC, the temperature of the semiconductor that has risen due to heat generation is increased. The heat is transferred to the heat dissipation plate 1 and each heat dissipation pin 3
... is transmitted to. In this case, the radiating pins 3 ... Have a star-shaped cross section (in this case, the protrusions 3A are provided at five places), and the middle radiating pin 4 has a large number of protrusions (in this case, the protrusions 3 in this case).
(A is provided at 10 places) and the concave portion 4C is provided at the tip to increase the surface area. Therefore, the heat transmitted from the IC can be easily released into the air.

In this way, since the surface area of the heat dissipation pin 3 is increased to improve the heat dissipation efficiency of the heat dissipation plate 1, even if the semiconductor heats up, the operation of the semiconductor itself becomes unstable, and the temperature of the semiconductor itself becomes unstable. It is possible to prevent the trouble that the semiconductor rises and the semiconductor is destroyed. Particularly, since the heat dissipation pin 3 is formed in a star shape and the recess 4C is provided at the tip of the middle heat dissipation pin 4 to increase the surface area of the heat dissipation pin 3 and the middle heat dissipation pin 4, the IC is transmitted to the heat dissipation plate 1. The generated heat can be radiated into the air very efficiently. Therefore, the heat dissipation efficiency of the heat dissipation plate 1 can be further improved.

Next, a heat dissipation pin 3 having another shape will be described with reference to FIGS. 6 to 9. In FIG. 6, a plurality of protrusions 3A ... (4 places in the embodiment) are provided on the side of the heat dissipation pin 3 to form a cross-shaped cross section. Further, in FIG. 7, a plurality of protrusions 3A ... (5 protrusions in the embodiment) are provided on the side of the heat dissipation pin 3 to form a starfish-shaped cross section. As a result, the surface area of the heat dissipation pin 3 is made extremely large and the heat dissipation efficiency of the heat dissipation plate 1 is greatly improved. This heat dissipation pin 3 is connected to the base plate 2 as described above.
A large number of them are provided in a grid pattern at predetermined intervals so as to project on one surface.

Similar to the above, the length of the radiation pin 3 is about 8.5 mm, the size of the tip is about 1.5 mm, and the size on the base plate 2 side is about 2.5 mm. It is formed so that the tip has a narrower slope so that it can be easily released from the mold after molding. Thus, the plurality of heat dissipation pins 3 ... Can be easily formed on the heat dissipation plate 2, and the heat dissipation plate 1 can be manufactured in a short time.

Further, in FIG. 8, a plurality of heat dissipation fins 3B ... (Five places in the embodiment) are provided on the heat dissipation pin 3, whereby the surface area of the heat dissipation pin 3 is further increased and the heat dissipation efficiency of the heat dissipation plate 1 is greatly increased. Has improved. As described above, a large number of the heat radiating pins 3 are provided on one surface of the base plate 2 in a grid pattern at predetermined intervals. The length of the heat dissipation pin 3 is, for example, about 8.5 mm, the size of the tip is about 1.5 mm, and the size of the base plate 2 side is about 2.5 mm, so that the tip is thinner than the base plate 2 side. A slope is provided so that the mold can be easily released from the mold. As a result, a plurality of heat dissipation pins 3,
・ ・ Can be easily molded.

Further, in FIG. 9, the radiation pin 3 is provided with a plurality of radiation fins 3B ... (16 places in the embodiment) so that the radiation pin 3 has a larger surface area to radiate the radiation of the radiation plate 1. Greatly improves efficiency. As described above, a large number of the heat radiating pins 3 are provided on one surface of the base plate 2 in a grid pattern at predetermined intervals. The length of the heat dissipation pin 3 is about 8.5 mm, and the size on the tip side is about 1.5
mm, the length is about 4 mm, and the base plate 2 side is provided with a slope like the heat dissipation pin. This allows the mold to be released more easily than the mold.

As described above, the heat dissipation pin 3 of the heat dissipation plate 1 has a star-shaped or cross-shaped cross section, and a plurality of protrusions 3A.
.. or a plurality of heat radiation fins 3B ... Are provided around the heat radiation pin 3, so that the heat radiation efficiency of the heat radiation plate 1 is significantly improved. Therefore, it is possible to prevent the problem that the operation of the semiconductor itself becomes unstable due to the heat generation, the problem that the semiconductor is destroyed by the temperature rise, and the like.

On the other hand, the heat dissipating pin 3 of the heat dissipating plate 1 is manufactured in an aluminum casting mold not shown, and the heat dissipating plate 1 is cast by this aluminum casting mold. Since the molten aluminum metal is poured into the aluminum casting mold, and is cooled and solidified, a plurality of heat dissipation pins 3 ... Can be formed on one surface of the base plate 2 in a short time. In this case, the radiating pin 3 is formed in a star-shaped cross-section, a cross-shaped cross-section, and a 100-foot cross-section, and a recess 4C of a predetermined shape is formed at the tip of the radiating pin 3.
Is provided. Thereby, the radiation pin 3 having an extremely large surface area can be formed.

As described above, by forming the plurality of heat dissipation pins 3 ... By casting, the heat dissipation plate 1 can be formed in an extremely short time. Therefore, a large labor cost such as manufacturing the heat sink 1 by cutting and manufacturing the heat sink 1 by a molding die as in the prior art is not required, so that the manufacturing cost of the heat sink 1 can be extremely reduced.

The heat radiating pin 3 of the heat radiating plate 1 is press-molded with a press die (not shown). Since such a press die is simply processed by inserting a predetermined aluminum plate and applying a strong pressure, a plurality of heat dissipation pins 3 ... Can be formed on one surface of the base plate 2 in a short time. In this case, the radiating pin 3 is formed in a star-shaped cross-section, a cross-shaped cross-section, and a 100-foot cross-section, and a recess 4C having a predetermined shape is provided at the tip of the radiating pin 3. Thereby, the radiation pin 3 having an extremely large surface area can be formed.

As described above, the heat dissipation plate 3 can be formed in an extremely short time by forming the heat dissipation pin 3 by applying a strong pressure with the press die. Therefore, a large labor cost such as manufacturing the heat sink 1 by cutting and manufacturing the heat sink 1 by a molding die as in the prior art is not required, so that the manufacturing cost of the heat sink 1 can be extremely reduced.

Although the dimensions of the heat dissipation plate 1 and the heat dissipation pin 3 are described in the embodiments, the present invention is not limited to this, and if the heat dissipation effect by the heat dissipation pin 3 can be obtained even if it is smaller than the described size or larger than the described size. The invention is effective. Also, the middle heat dissipation pin 4
Although the recess 4C is provided at the tip of the above, the present invention is not limited to this, and the surface area of the heat dissipation pin 3 may be increased by providing a not shown recess at the tip of the heat dissipation pin 3.

Further, although the protrusions are provided at four or five places around the heat radiating pin 3, the present invention is not limited to this, and the number of protrusions may be more or less than four or five. Further, although the fins are provided around the heat radiating pin 3 at five locations or at 16 locations, the number of protrusions is not limited to this and may be more or less than 5 locations or 16 locations.

Further, the heat sink 1 of the present invention has been described by naturally radiating the heat transmitted from the IC into the air from the plurality of heat radiating pins, but the present invention is not limited to this. It goes without saying that further improvement in heat radiation performance can be expected by using it for a heat radiation plate using a flow fan or the like. Furthermore, although the heat dissipation plate 1 of the present invention is applied to heat dissipation of a semiconductor such as an IC in the embodiments, the present invention is effective for any heating element such as other brakes.

[0045]

As described in detail above, according to the first aspect of the invention, since a plurality of heat dissipation pins provided on one surface of the base plate of the heat dissipation plate have a star-shaped cross section, heat dissipation of a round pillar or a prism having the same thickness is performed. It is possible to make the surface area of the heat dissipation pin extremely large with respect to the pin. Thereby, the heat dissipation efficiency of the heat dissipation plate can be significantly improved. Therefore, a large amount of heat is generated I
When attached to C or the like, it is possible to prevent the temperature of the IC from rising due to natural heat dissipation.

Further, according to the invention of claim 2, since a plurality of protrusions are provided around a plurality of heat dissipation pins provided on one surface of the base plate of the heat dissipation plate, a heat dissipation pin of a round pillar or a prism having the same thickness can be provided. On the other hand, the surface area of the heat dissipation pin can be made extremely large. Thereby, the heat dissipation efficiency of the heat dissipation plate can be significantly improved. Therefore, when attached to an IC or the like that generates a large amount of heat, it is possible to prevent the temperature of the IC from rising due to natural heat dissipation.

According to the invention of claim 3, since a plurality of fins are provided around a plurality of heat dissipation pins provided on one surface of the base plate of the heat dissipation plate, a heat dissipation pin of a round pillar or a prism having the same thickness can be used. On the other hand, the surface area of the heat dissipation pin can be made extremely large. Thereby, the heat dissipation efficiency of the heat dissipation plate can be significantly improved. Therefore, an IC that generates a large amount of heat
When it is attached to the same or the like, it is possible to prevent the temperature of the IC from rising due to natural heat dissipation.

Further, in the heat dissipation plate 1 of the invention of claim 4, in the above-mentioned claim 1, claim 2 or claim 3, since the recess is provided at the tip of the heat dissipation pin, the surface area of the heat dissipation pin should be further increased. Is possible. As a result, the heat dissipation efficiency of the heat dissipation plate can be further greatly improved. Therefore, when attached to an IC or the like that generates a large amount of heat, it is possible to prevent the temperature of the IC from rising due to natural heat dissipation.

Further, according to the invention of claim 5, in the above-mentioned claim 1, claim 2, claim 3 or claim 4,
Since the heat sink is formed by casting an aluminum material to form the heat sink, the heat sink can be manufactured in an extremely short time. Therefore, a large amount of heat sinks can be cast and molded in a short period of time, and the manufacturing cost of the heat sinks can be reduced.

Further, according to the invention of claim 6, in claim 1, claim 2, and claim 3, since the heat sink is press-molded, the heat sink can be molded in an extremely short time. . Therefore, a large amount of heat sinks can be press-molded in a short period of time, and the manufacturing cost of the heat sinks can be reduced.

[Brief description of the drawings]

FIG. 1 is a front view of a heat sink of the present invention.

FIG. 2 is a side view of a heat sink of the present invention.

FIG. 3 is a front view of a heat dissipation pin of the present invention.

FIG. 4 is a side view of the heat dissipation pin of the present invention.

FIG. 5 is a cross-sectional view of a molding die for a heat sink of the present invention.

FIG. 6 is a front view of another heat dissipation pin of the present invention.

FIG. 7 is a front view of another radiation pin.

FIG. 8 is a front view of another radiation pin.

FIG. 9 is a front view of yet another heat dissipation pin.

FIG. 10 is a front view of a heat dissipation plate in which other heat dissipation pins are arranged in a staggered pattern.

11 is a side view of the heat sink of FIG.

FIG. 12 is a front view of a heat dissipation plate in which other heat dissipation pins are arranged in a grid pattern.

13 is a side view of the heat sink of FIG.

[Explanation of symbols]

 1 heat sink 2 base plate 3 heat sink pin 3A protrusion 3B heat sink fin 4 middle heat sink pin 10 die casting mold 12 vacuum chamber 13 heat sink pin molding part

Claims (6)

[Claims] 1. A heat dissipation plate having a plurality of heat dissipation pins provided on one surface of a base plate, wherein the heat dissipation pin has a star-shaped cross section. 2. A heat dissipation plate having a plurality of heat dissipation pins provided on one surface of a base plate, wherein a plurality of protrusions are provided around the heat dissipation pins. 3. A heat dissipation plate having a plurality of heat dissipation pins provided on one surface of a base plate, wherein a plurality of heat dissipation fins are provided around the heat dissipation pins. 4. The heat radiating plate according to claim 1, wherein the heat radiating pin has a recess at its tip. 5. The heat radiating plate according to claim 1, 2, 3, or 4, wherein the heat radiating plate is formed by casting an aluminum material. 6. The heat dissipation plate according to claim 1, wherein the heat dissipation plate is a press-molded aluminum material.