JP2002111259A - Radiator for electronic appliance - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a radiator for electronic appliances which is small-sized and has a high radiating effect. SOLUTION: The radiator for electronic appliances so has parallel-flat- plate-form radiating fins 3 and the group of fin pieces 7 as to make attachable a heat generating body to the portion provided with the group of the fin pieces.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a heat radiator for an electronic device used for heat radiation of a high heat component, a high heat unit, and the like used in the electronic device.

[0002]

2. Description of the Related Art In recent years, electronic devices have been reduced in size and weight, and the mounting density of electronic components has been increased.
The amount of heat generated has increased with the increasing functionality of electronic units.
In order to maintain and stabilize the performance of electronic components and electronic units, cooling is indispensable, and heat-generating components and heat-generating units that require cooling are mounted on a radiator provided with radiating fins. If there are a large number of heat-generating components and heat-generating units that require cooling, they are collectively mounted on a radiator having large parallel plate-shaped heat-radiating fins.

With reference to FIGS. 12 and 13, a radiator of a conventional electronic device will be described.

In FIG. 1, reference numeral 1 denotes a radiator, which is formed of an aluminum material or the like. The radiator 1 includes a base 2 and fins 3 provided in parallel with the base 2 at a predetermined pitch. A heating element 4 such as an electronic component or an electronic unit is fixed to the base 2 with a bolt or the like.

The heat generated from the heating element 4 is transmitted to the fins 3 via the base 2 and is radiated from the surface of the fins 3. If the heat release is not sufficient, a cooling fan 5 is provided to perform forced air cooling.

The cooling fan 5 is provided at one end of the radiator 1.
Are provided, and the direction of the fins 3 is parallel to the blowing direction of the cooling fan 5.

The heat from the heating element 4 is transmitted to the fins 3 via the base 2, and the cooling air blown from the cooling fan 5 passes through the grooves 6 between the fins 3. Thereby, heat is transferred from the fins 3 to the cooling air, and the heat radiation amount of the radiator 1 increases.

[0008]

When the cooling air passes through the groove 6 formed by the fins 3, 3, the cooling air easily flows in the center of the groove 6 due to the flow path resistance, and the air velocity passing near the surface is low. Become slow. For this reason, a temperature boundary layer is formed along the surface of the fin 3, and this temperature boundary layer reduces the heat transfer coefficient between the fin 3 and the cooling air, so that the heat radiation effect from the fin 3 is reduced. Further, the temperature boundary layer tends to become thicker as the flow rate of the cooling air decreases, and the fins 3
When the length was longer, the temperature boundary layer became thicker on the downstream side, and the heat radiation effect was also reduced.

Next, the heat radiation capacity of the radiator 1 largely depends on the heat radiation area, but it is conceivable to narrow the pitch of the fins 3 in order to increase the heat radiation area. When the pitch is reduced and the width of the groove 6 is reduced, the flow path resistance increases,
The flow rate of the cooling air decreases, and the heat transfer coefficient decreases. Further, the proximity of the fins 3 may cause the temperature boundary layers to overlap. Therefore, there is a limit to reducing the pitch of the fins 3.

Further, auxiliary means such as a heat pipe may be provided to increase the amount of heat radiated by the radiator 1. In this case, the amount of heat radiation increases, but the cost increases, and further provision of auxiliary means imposes restrictions on the design such as the installation position of the radiator 1.

Therefore, at present, there is a problem that when the heat radiation amount of the high heat generating component depends only on the radiator, the radiator must be enlarged. Further, if the radiator is too large relative to the size of the high heat-generating component, the heat radiation efficiency is reduced.

The present invention has been made in view of the above circumstances, and has as its object to provide a radiator for an electronic device which is small and has a high heat radiation effect.

[0013]

SUMMARY OF THE INVENTION The present invention has a radiating fin having a shape of a parallel plate and a group of fins provided at a predetermined interval, and a heating element is attached to a portion where the group of fins is provided. The present invention relates to a radiator of an electronic device as described above.

[0014]

Embodiments of the present invention will be described below with reference to the drawings.

A first embodiment of the present invention will be described with reference to FIGS.

1 to 3, the same components as those shown in FIGS. 12 and 13 are denoted by the same reference numerals.

The radiator 1 comprises a base 2, a plate-like fin 3 formed on the base 2, and a fin piece 7 in the form of a cylindrical rod.

Although not shown, the cooling fan 5 is provided below the radiator 1. Single or multiple electronic components,
A heating element 4 having a high calorific value in the electronic unit is provided at a lower portion of the base 2 of the radiator 1 at an inlet side into which cooling air flows.

The fins 3 are formed on a surface of the base 2 opposite to a portion on which the heating element 4 is mounted.
The area facing the portion where the is mounted is cut off, and instead the fin pieces 7 are erected so as to have a uniform distribution, and the fin pieces 7 form a fin group. As the mode of standing, for example, a required row and a required stage (seven rows in the drawing,
(Four stages) in a matrix, and the pitch of the rows is smaller than the pitch of the fins 3.

The state of heat radiation in the radiator 1 will be described.
The heat from the heating element 4 is more likely to move in a direction perpendicular to the contact surface than to move along the contact surface of the heating element 4 (spread along the base 2). Therefore, heat from the heating element 4 is mainly transmitted to the fin pieces 7 via the base 2.

The entire surface of the fin pieces 7 serves as a heat radiating surface, and the heat radiating surface can be increased by independently standing upright. Further, by making the pitch of the rows of the fin pieces 7 smaller than the pitch of the fins 3, the entire heat radiation area can be increased. In addition, since the cooling air collides with the fin pieces 7 and flows between the fin pieces 7 while being stirred, a temperature boundary layer is not easily formed on the surface of the fin pieces 7.

Heat is efficiently transferred from the heating element 4 to the fin pieces 7, and the heat radiation effect is improved by increasing the heat radiation area and suppressing the temperature boundary layer.

It is conceivable that the provision of a large number of the fin pieces 7 may increase the flow path resistance. However, the fin pieces 7 are provided at a location near the cooling fan 5 where the cooling air flow rate is large. Limited and sufficient flow for cooling is obtained. Furthermore, in the portion where the fins 3 are provided after passing through the group of fin pieces 7, the cooling air is rectified and circulated, so that the flow path resistance is small. Thus, the fin piece 7 and
Since the fins 3 are used in combination, the amount of heat radiation is increased at the fin pieces 7 and the flow path resistance is not greatly increased as a whole, and a sufficient cooling air flow rate can be obtained.

The sum of the radiating areas of the fin pieces 7 and the fins 3 is equal to that in the case where only the fins 3 are provided.
It goes without saying that even if the number and the shape of the fin pieces 7 are selected, the heat radiation effect similarly increases.

FIG. 4 shows a second embodiment, in which fin pieces 8 each having a prismatic shape having a different shape are provided in place of the fin pieces 7.

FIGS. 5 and 6 show the third embodiment, in which the fin pieces 7 in the first and second embodiments are replaced by cylindrical fin pieces 9. The posture in which the fin pieces 9 are provided is such that the axis of the cylindrical curved surface is
And parallel.

As shown in the second and third embodiments, by changing the shape of the fin pieces, the surface area (radiation area) of the fin pieces and the state of the cooling air flowing between the fin pieces change. Therefore, the heat radiation effect is different. Therefore, the number and shape of the fin pieces are selected according to the required heat radiation amount.

Furthermore, the fin pieces are arranged in a matrix, but the arrangement of the fin pieces may be variously selected, for example, the rows are arranged in a zigzag manner.

Next, a fourth embodiment will be described with reference to FIGS.

In the fourth embodiment, the fin pieces 7 are provided separately from the base 2.

A portion of the fin 3 facing the portion where the heating element 4 is mounted is cut off, and the sub radiator 11 is fixed to the portion of the base 2 where the fin 3 is cut off by a fastener such as a bolt. You. The sub radiator 11 has a flat plate portion 12.
The fin pieces 7 in the form of a cylindrical rod are formed upright, and the number and arrangement of the fin pieces 7 are the same as those of the first embodiment shown in FIG. 1 in a state where the sub radiator 11 is attached to the base 2. It is the same as the embodiment.

By forming the fin pieces 7 separately from the base 2, the radiator 1 can be manufactured by extrusion molding, for example, thereby facilitating the manufacturing and reducing the manufacturing cost. or,
The components of the sub radiator 11 are also reduced in size and can be easily manufactured by a method such as die casting. Further, the fin pieces 7 are formed as separate parts from the flat plate portion 12, and are pressed into the flat plate portion 12,
Various manufacturing methods such as planting by welding or the like can be adopted.

FIGS. 9 and 10 show application examples of the fourth embodiment.

FIG. 9 shows a sub-radiator 11 in which a fin piece 8 in the form of a prismatic bar is erected on the flat plate portion 12 instead of the fin piece 7, and the one shown in FIG. The sub-radiator 11 is formed by erecting fin pieces 9 having a cylindrical curved surface.

By changing the fin pieces, the sub radiator 11
Since the heat radiation performance of the heat generating element changes, it is possible to select an appropriate fin piece according to the heat generation amount of the heat generating element.

[0036]

As described above, according to the present invention, a heating element having a high calorific value is provided on the cooling fluid inflow side of the radiator, and the fin of the portion where the heating element is provided is a fin piece. The heat radiation effect of the portion where the body is provided is increased, and the heating element can be effectively cooled. In addition, since an auxiliary means for increasing the cooling effect is not used, it is possible to cope at a low cost. It has an excellent effect.

[Brief description of the drawings]

FIG. 1 is a front view showing a first embodiment of the present invention.

FIG. 2 is a side view showing the first embodiment.

FIG. 3 is a bottom view showing the first embodiment.

FIG. 4 is a front view showing a second embodiment of the present invention.

FIG. 5 is a front view showing a third embodiment of the present invention.

FIG. 6 is a view as viewed in the direction of arrows AA in FIG. 5;

FIG. 7 is a front view showing a fourth embodiment of the present invention.

FIG. 8 is a bottom view showing the fourth embodiment.

FIG. 9 is a front view showing an application example of the fourth embodiment.

FIG. 10 is a front view showing another application example of the fourth embodiment.

11 is a view taken in the direction of arrows BB in FIG. 10;

FIG. 12 is a front view of a conventional example.

FIG. 13 is a side view of a conventional example.

[Explanation of symbols]

 REFERENCE SIGNS LIST 1 radiator 2 base 3 fin 4 heating element 5 cooling fan 6 groove 7 fin piece 8 fin piece 9 fin piece 11 sub radiator 12 flat plate

 ────────────────────────────────────────────────── ─── Continued on the front page (72) Inventor Masahiro Umezaki 3-14-20 Higashinakano, Nakano-ku, Tokyo Kokusai Denki Co., Ltd. F-term (reference) 5E322 AA01 AB11 BA05 5F036 AA01 BA04 BA24 BB01 BB05 BB06

Claims (1)

[Claims] 1. A radiating fin having a shape of a parallel plate and a fin group provided at a predetermined interval, wherein a heating element is attached to a portion where the fin group is provided. Radiator for electronic equipment.