JPH08195453A - Heat dissipation plate - Google Patents

Abstract

PURPOSE: To enhance heat dissipation efficiency by arranging heat dissipation pins at a predetermined interval on multiple imaginary lines extending radially from the center of a base thereby improving ventilation between the heat dissipation pins. CONSTITUTION: The heat dissipation plate 1 for dissipating heat generated from a semiconductor including an integrated circuit, e.g. an IC, into the air and cooling the semiconductor comprises a base 2 and multiple pins 3,... arranged at a predetermined interval on one side of the base 2. The base 2 of the heat dissipation plate 1 for absorbing heat from the semiconductor and transmitting the heat to the heat dissipation pins 3 is secured to the semiconductor and made of a light metal having high thermal conductivity, e.g. aluminum. The base 2 is arranged, on one side thereof, with multiple heat dissipation pins 3 and can be fixed, on the other side thereof, to one side of an IC, for example. The multiple heat dissipation pins 3 are arranged, at a predetermined interval, on a large number of imaginary lines 4 extending radially from the center of the base 2 and the lengths of heat dissipation pins 3 corresponding to alternate imaginary lines 4,... are differentiated (i.e., long heat dissipation pins 3A and short heat dissipation pins 3B).

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION The present invention relates to a heating element such as a semiconductor,
In particular, the present invention relates to a heat sink suitable for an integrated circuit including 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. Further, the semiconductor of this IC generates a large amount of heat in the process of operating, and when the temperature rises, the operation of the semiconductor itself becomes unstable. Then, if the temperature of the semiconductor further rises, the semiconductor will be destroyed. Therefore, a heat sink that cools the semiconductor is attached to the IC, heat is exchanged between the heat sink and the air to release the heat of the semiconductor into the air, and the semiconductor is prevented from becoming hot and unstable in operation or destroyed. There is.

A conventional heat dissipation plate is provided with a large number of thin plate fins at a predetermined interval on one surface of a base made of metal such as aluminum, which makes the contact area between the heat dissipation plate and air wide. To improve the heat dissipation performance, especially for ICs equipped with semiconductors that generate a large amount of heat,
Instead of the thin plate fins, a large number of elongated heat dissipation pins are arranged and attached in a grid pattern to further increase the contact area between the heat dissipation plate and air to obtain a larger heat dissipation effect.

In the case of such (the latter) heat dissipation plate, conventionally, a large number of thin and long heat dissipation pins were formed by cutting on one surface of the base, but in that case, a milling machine or the like is used to cut each row vertically and horizontally. It takes a lot of time and labor for cutting, and one side is a square with a length of 1 mm to 2 mm and a length of 1
When a heat dissipation pin having a length of 0 mm or more is cut, it is difficult to realize stable processing because the heat dissipation pin is bent or chipped during cutting.

Therefore, in recent years, a method has been developed in which a thin and long radiating pin can be easily formed with a simpler structure as described below. That is, in this case, a mold provided with a large number of thin and long holes is made of resin, and the heat-melted aluminum is poured into the mold to integrally form the radiation pin with the base. Then, the resin mold is melted and removed with a predetermined chemical to obtain a heat dissipation plate in which thin and long heat dissipation pins are formed in a grid pattern on one surface of the base.

The radiator plate is attached to the IC in a heat exchange manner, and an axial fan (propeller fan) is usually attached to the tip of the radiator pin. When the radiator plate is air-cooled to cool the semiconductor, When air is blown onto the heat sink to cool it, the heated air is diffused around the semiconductor and IC
The heat of the surrounding parts causes the temperature to rise, resulting in unstable operation or destruction. Therefore, generally, for cooling the heat dissipation plate, a method is adopted in which the air around the heat dissipation plate is moved toward the center of the base, and the air is sucked and discharged to the outside. In addition, since the surface area of the heat dissipation plate is larger when the heat dissipation pins provided on the heat dissipation plate of a limited size are thin and long and densely arranged, the density of the heat dissipation pins increases as the size of the IC decreases. Tended to be accelerated.

[0007]

When air is sucked by the fan, the air around the radiator plate flows toward the center of the base. That is, the sucked air flows from the outside toward the center on the imaginary line radiating from the center of the base of the heat radiating plate while exchanging heat with the heat radiating pin. On the other hand, in the conventional heat radiating plate, a large number of heat radiating pins are arranged in a grid pattern on one surface of the base, so that the resistance of the heat radiating pin to the flow of air increases. In particular, as described above, when the density of the heat radiating pins is high, the heat radiation performance is lowered due to the deterioration of ventilation, or the level of the heat is reached, and the noise is increased.

Further, when the air is sucked by the axial fan, the air flows while swirling toward the center of the base, so that the air resistance is further increased.

The present invention has been made in order to solve the problems of the prior art, and it is an object of the present invention to provide a heat dissipation plate having improved heat dissipation efficiency by improving ventilation between the heat dissipation pins. And

[0010]

That is, the heat radiating plate 1 according to the invention of claim 1 has a large number of heat radiating pins 3 ...
The heat dissipating pins 3 are arranged at predetermined intervals on a large number of virtual lines 4 ... Emitted from the center of the base 2.

According to a second aspect of the present invention, there is provided a heat radiating plate 1 having a large number of heat radiating pins 3 on one surface of a base 2.
A large number of virtual lines 4 that radiate spirally from the center of the base 2.
The heat radiation pins 3 are arranged on the upper side at a predetermined interval.

Further, the heat radiating plate 1 of the invention of claim 3 is the same as in each of the above inventions, in which the length of each of the heat radiating pins 3 ...

Further, the heat dissipation plate 1 of the invention of claim 4 is the heat dissipation plate 3 according to the invention of claim 1 or 2,
.. The cross-sectional shape of the tree is leaf-shaped, and the virtual lines 4 ...
・ It is oriented in the direction of extension.

[0014]

According to the heat radiating plate 1 of the invention of claim 1, since the heat radiating pins 3 ... Are arranged on a large number of virtual lines 4 ... The heat radiating pins 3 are arranged along the flow of air toward the center of the base (or from the center of the base 2 to the outside). Therefore, the ventilation resistance of the air flowing between the heat radiating pins 3 can be remarkably reduced, and the air flow can be made extremely smooth to improve the heat radiation efficiency.

According to the heat radiating plate 1 of the invention of claim 2, since the heat radiating pins 3 ... Are arranged on a large number of spiral virtual lines 4 ... Radiating from the center of one surface of the base 2, Especially when an axial fan is used, the heat dissipation pins 3 ... Are arranged along the air flow from the outside toward the center of the base 2 (or from the center of the base 2) while swirling. Become. Therefore, the ventilation resistance of the air flowing between the heat radiating pins 3 can be remarkably reduced, and the air flow can be made extremely smooth to further improve the heat radiation efficiency.

According to the heat dissipation plate 1 of the third aspect of the present invention, in addition to the above respective inventions, the length of a large number of the heat dissipation pins 3 provided on one surface of the base 2 has height differences. , A heat dissipation pin 3 at the air inlet (or outlet) to the heat dissipation plate 1
・ The density of can be made sparse and the ventilation performance can be further improved.

Further, according to the heat dissipation plate 1 of the invention of claim 4, in addition to the invention of claim 1 or 2, each heat dissipation pin 3 is provided.
The cross-sectional shape of ... Is made to be a leaf shape, and the heat dissipation pins 3 ... Are oriented in the extending direction of the virtual lines 4 ... In addition to being able to reduce the amount of heat, heat can be efficiently radiated from the edge portion of the leaf shape, and the heat radiation efficiency can be further improved.

[0018]

Embodiments of the present invention will now be described in detail with reference to the drawings. 1 is a front view of a heat sink 1 of the present invention, FIG. 2 is a side view of the heat sink 1 of the present invention, and FIG. 3 is a cross-sectional view of a die casting mold 10 of the heat sink 1 of the present invention. 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 the base 2 and a large number of heat radiating pins arranged on one surface of the base 2 at a predetermined interval. It consists of 3 ...

The base 2 of the heat radiating plate 1 is for absorbing the heat of the semiconductor and transmitting it to the heat radiating pin 3 and fixing it to the semiconductor, and is made of a metal such as aluminum having a high thermal conductivity and a light weight. A large number of heat dissipation pins 3 to be described later are provided on one surface of the base 2, and the other surface of the base 2 can be easily attached to one surface of an IC or the like. And
A mounting hole (not shown) for mounting on an IC or the like is provided in the base 2 at a predetermined position.

The heat dissipation pins 3 are provided so as to protrude from the center of the base 2 on a plurality of virtual lines 4 ... Further, there is a height difference (indicated by a long radiating pin 3A and a short radiating pin 3B) in the length of the radiating pins 3 ... Corresponding to the alternate virtual lines 4 ...
A is, for example, a quadrangle (diamond in the example) having a side of 1 mm to 2 mm and a length of 20 mm to 30 mm, and the short heat dissipation pin 3B is a quadrangle (diamond in the example) having a side of 1 mm to 2 mm and a length of 10 mm to 25 mm. Is the length.

Next, the procedure for forming 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. Then, the heat dissipation pin portion 13 of the molding die 11 of the heat dissipation plate 1
A vacuum chamber 12 is provided so as to communicate with the tip of the vacuum chamber 12, and the vacuum chamber 12 is provided with a breathable material (not shown).
Air easily passes through this breathable material, but the molding material (aluminum or the like) of the heat dissipation plate 1 does not easily pass through. A pipe 14 equipped with a vacuum pump (not shown) is connected to one of the vacuum chambers 12 via a limit switch (not shown), and the other end of the vacuum chamber 12 is a pipe 15 for discharging compressed air via a limit switch (not shown). Are connected.

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 (not shown) for easily taking out the heat sink 1 is applied to the molding die 11 of the heat sink 1, and the die (cavity side die 10A and core side die 10A
Close B). Then, the limit switch of the pipe 15 connected to the other side of the vacuum chamber 12 is closed, the limit switch of the pipe 14 connected to one side is opened, and the air in the vacuum chamber 12 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) (aluminum in this case) melted at + 680 ° C. to + 700 ° C. is applied with a predetermined pressure using a hydraulic cylinder or the like (not shown) to form the molding die 1.
Fill within 1. At this time, since the inside of the mold 11 is in a vacuum state, the molten aluminum material can be easily filled, and the radiation pin portions 13 ... Easily flows into the tips of the heat dissipation pin 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.

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. Then, the cavity side mold 10A of the die casting mold 10 is cooled in a state where the aluminum in the mold 11 is solidified by cooling for a predetermined time.
Then, the core side mold 10B is opened, the vacuum pump is stopped, and the limit switch of the one pipe 14 is closed. Then, the limit switch of the other pipe 15 is opened to blow compressed air into the vacuum chamber 12 for a predetermined time, and the radiator plate 1 is pushed out from the mold 11 by an ejector pin (not shown).
The heat sink 1 is taken out.

Further, by blowing compressed air into the vacuum chamber 12, dust (aluminum material residue, etc.) adhered to the molding die 11, particularly a large number of the radiation pin portions 13 ... Or the breathable material when the radiation plate 1 is molded. (For example, carbon) to prevent the dust from adhering to the molding die 11, the breathable material, etc. and clogging, and at the same time, the heat sink 1 and the molding die 1
Cool 1st etc. Then, the heat sink 1 is taken out from the molding die 11 and subjected to a predetermined process such as deburring that has been performed during molding or finishing of the contact surface between the base 2 surface and the IC to complete the heat sink 1.

According to the die-cast molding die 10 as described above, since the heat sink 1 can be molded without using a conventional resin mold, there is no need to melt the resin, and the manufacturing cost is greatly reduced. Can be planned.

Next, an example of using the heat sink 1 will be described. First, a predetermined IC or the like is attached to an electric circuit (not shown), and the other surface of the base 2 of the heat dissipation plate 1 is closely attached to a predetermined position of the IC to fix the attachment hole with a screw (not shown). Then, a suction type axial fan (not shown) is made to face the center of one surface of the base 2 of the heat radiating plate 1, and a small clearance is provided between the tip of the heat radiating pin 3 ... To install.

When a switch (not shown) of the electric circuit is turned on, the semiconductor operates to generate heat, and at the same time the fan also operates to rotate, so that the air around the radiator plate 1 is rotated by a large number of radiator pins 3. Aspirate through. The sucked air flows from the outside of the heat dissipation plate 1 toward the center of the base 2,
At this time, since the heat dissipation pins 3 ... Are arranged on a large number of virtual lines 4 ... Radiating from the center of one surface of the base 2, the heat dissipation pins 3 ... Are arranged along the air flow. Will be.

Therefore, the ventilation resistance of the air flowing between the heat radiating pins 3 is remarkably reduced, the air flow becomes extremely smooth, and the heat from the semiconductor is smoothly dissipated. Problems such as unstable operation and damage of the semiconductor can be prevented.

In particular, in the case of FIG. 1, the density of the heat radiating pins 3, ... Is sparse in the outer peripheral portion of the base 2 which is the inlet of the air flow, and the heat radiating pins 3 ,. Therefore (radiation pins 3A, 3B), the density of the radiation pins 3 at the outlet of the air flow is also sparse. Therefore, air easily enters or exits the heat dissipation plate 1, so that the ventilation performance can be further improved.

Next, in FIG. 4 to FIG. 6, a large number of radiating pins 3 radiating spirally (right-handed or left-handed) from the center of the base 2 ... ... is provided. And each radiation pin 3 ...
Are directed in the direction of extension of the virtual lines 4 ..., and the height difference between the heat radiation pins 3 ... Corresponding to the alternate virtual lines 4 ... Is indicated by the heat radiation pins 3A (long ones and heat radiation pins 3B, short ones). ) Is attached.

Here, when the axial fan rotates, air is actually sucked in a vortex along the rotation, but in the present invention, the radiation pins 3 ... Are radiated from the center of one surface of the base 2. Since they are arranged on a large number of vortex-shaped imaginary lines 4 ..., the radiating pins 3 ... Are arranged along the air flow from the outside toward the center of the base 2 while swirling as described above. become. Therefore, the ventilation resistance of the air flowing between the heat radiating pins 3 is remarkably reduced, the air flow is made extremely smooth, and the heat radiation efficiency is further improved, and the noise can be reduced.

In particular, the cross-sectional shape of each of the heat radiating pins 3 ... Is a leaf shape, and the heat radiating pins 3 ...
Since it is oriented in the extending direction of, the air resistance that collides with the heat dissipation pins 3 ... Can be further reduced, and heat can be efficiently dissipated from the edge portion of the leaf shape, and the heat dissipation efficiency can be improved. It is possible to further improve.

Further, as shown in FIG. 7 and FIG.
Is radiated from the center of one surface of the base 2 with a number of virtual lines 4
... A large number of long radiating pins 3A arranged above
, And a short radiating pin 3C having a cylindrical shape (in this case, a square shape may be used) provided between the radiated radiating pin 3A and a rough portion on the outer side. In this case, as shown in FIG. 1, the heat dissipation pins 3 are denser, and the heat dissipation area of the heat dissipation plate 1 is further increased.

Further, in the above embodiment, a large number of heat radiation pins 3 are arranged on the virtual line 4 ...
.. are arranged and the heat radiation pins 3 corresponding to the alternate virtual lines 4 ... Are provided with different heights. However, this is not restrictive, and the heat radiation pin 3 in the central portion of the base 2 is arranged as shown in FIG. The ventilation resistance may be lowered by lowering it and the outer peripheral portion may be raised by lowering it. Further, as shown in FIG. 10, the radiating pin 3 at the center of the base 2 may be raised and the outer peripheral portion may be lowered to reduce the ventilation resistance.

In the embodiment, the radiating pins 3 ... Are formed in the shape of a square (diamond), circle or leaf, but the present invention is not limited to this and the present invention is also effective. Is. Further, in the embodiment, the case where the suction type axial flow fan is used has been described, but the present invention is effective even if it is a discharge type axial flow fan. Further, in the embodiment, the heat sink 1
Although the axial fan is provided so as not to come into contact with the heat dissipation pin 3 so as to face the center of one surface of the base 2, the present invention is not limited to this. The present invention is also effective when the heat dissipation plate 1 and the fan are integrated by installing a small fan in this mounting hole.

Further, although only the forced air cooling by the fan has been described in the embodiment, it is needless to say that even if the heat is radiated by natural convection, the air flow can be smoothed and the heat radiation performance can be improved. Further, although the heat dissipation plate 1 of the present invention is applied to the heat dissipation of the semiconductor in the embodiment, the present invention is effective for any heating element such as other brakes.

[0038]

As described in detail above, according to the invention of claim 1, since the heat dissipation pins are arranged on a large number of imaginary lines radiating from the center of one surface of the base, from the outside to the center of the base (or the center of the base). The heat radiating pins are arranged along the flow of air from the outside (to the outside). Therefore, the ventilation resistance of the air flowing between the heat radiating pins can be remarkably reduced, and the air flow can be made extremely smooth to improve the heat radiation efficiency.

According to the second aspect of the present invention, since the heat radiation pins are arranged on a large number of vortex-shaped virtual lines radiating from the center of one surface of the base, the whirlpool is generated when the axial fan is used. The heat dissipation pins are arranged along the air flow from the outside to the center of the base (or from the center of the base to the outside). Therefore, the ventilation resistance of the air flowing between the heat radiating pins can be significantly reduced, and the air flow can be made extremely smooth to further improve the heat radiation efficiency.

Further, according to the invention of claim 3, in addition to the above-mentioned inventions, since the length of a large number of heat radiation pins provided on one surface of the base has height differences, the air inlet to the heat radiation plate (or The density of the radiation pins at the outlet) can be made sparse, and the ventilation performance can be further improved.

Furthermore, according to the invention of claim 4, in addition to the invention of claim 1 or claim 2, the cross-sectional shape of each radiating pin is made into a leaf shape, and each radiating pin is arranged in the extending direction of the imaginary line. Since it is oriented, it is possible to further reduce the air resistance that collides with the heat dissipation pin, and it is possible to efficiently dissipate heat from the edge portion of the leaf shape, and it is possible to further improve heat dissipation efficiency.

[Brief description of 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 cross-sectional view of a molding die for a heat dissipation plate of the present invention.

FIG. 4 is a front view of a heat dissipation plate in which leaf-shaped heat dissipation pins are arranged spirally.

5 is a front view of a heat dissipation plate in which the leaf-shaped heat dissipation pins of FIG. 4 are arranged in an opposite spiral shape.

6 is a side view of the heat sink of FIGS. 4 and 5. FIG.

FIG. 7 is a front view of a heat dissipation plate in which a heat dissipation pin is provided on a rough portion outside the heat dissipation pin.

FIG. 8 is a side view of the heat dissipation plate of FIG.

FIG. 9 is a side view of a heat dissipation plate in which a heat dissipation pin on the outer periphery is high and a center is low.

FIG. 10 is a side view of a heat dissipation plate in which a heat dissipation pin on the outer circumference is low and a center is high.

[Explanation of symbols]

 1 heat sink 2 base 3 heat sink pin 4 virtual line 10 die casting mold 12 vacuum chamber 13 heat sink pin section

Claims (4)

[Claims] 1. A heat dissipation plate having a large number of heat dissipation pins provided on one surface of a base, wherein the heat dissipation pins are arranged at predetermined intervals on a plurality of virtual lines radiating from the center of the base. 2. A heat dissipation plate having a large number of heat dissipation pins provided on one surface of a base, wherein the heat dissipation pins are arranged at predetermined intervals on a plurality of virtual lines radiating spirally from the center of the base. Board. 3. The heat radiating plate according to claim 1, wherein the length of each heat radiating pin is different in height. 4. The cross-sectional shape of each radiating pin is a leaf shape,
The radiator plate according to claim 1 or 2, wherein the radiator plate is oriented in the extending direction of the virtual line.