JP2003008269A - Mounting structure of axial fan - Google Patents

Abstract

PROBLEM TO BE SOLVED: To decrease fan noises, without increasing the number of production or requiring additional parts and to enhance the cooling efficiency. SOLUTION: In a mounting structure of an axial fan, the axial fan 2 is mounted to a mounting surface 1a of an internal surface of a case, and an air direction is directed to the inside of the case. A spacer 1c of a predetermined height is provided, surrounding a mounting screw 3 between the mounting surface 1a and the axial fan 2.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a mounting structure for an axial fan used to radiate heat inside electric equipment such as a switching power supply.

[0002]

2. Description of the Related Art Generally, in order to radiate heat inside an electric device such as a switching power supply, an axial fan is attached to a mounting surface of an inner surface of the electric device, for example, an inner surface of a front plate so that a wind direction can flow inside the housing. ing.

Conventionally, as shown in FIGS. 3 and 11, the axial fan 2 is conventionally attached to the inner surface of the front plate 1a provided with the air holes of the housing of the electric device 1 such as a switching power source. It was attached directly with the screw 3.

When the axial fan 2 is directly attached to the inner surface of the front plate 1a of the housing of the electric device 1, the electric device 1
There was a problem that the wind speed inside the housing was relatively slow, the cooling efficiency was relatively poor, and the fan noise such as wind noise was relatively large.

Conventionally, in order to reduce the fan noise and improve the cooling efficiency, as shown in FIG. 12, a synthetic resin is provided between the inner surface of the front plate 1a having the air holes of the electric device 1 and the axial fan 2. Alternatively, a rectangular frame 4 made of metal and having a predetermined thickness
The axial fan 2 and the inner surface of the front plate 1a of the housing.
And a predetermined space is provided between and.

[0006]

However, when a square frame 4 is provided between the inner surface of the front plate 1a of the housing of the electric device 1 and the axial fan 2, the square frame 4 is formed. However, there is a disadvantage that it becomes an additional part and the cost is increased, and a work for assembling the rectangular frame 4 is required, and accordingly, there is a disadvantage that the number of manufacturing steps is increased.

In view of this point, the present invention aims to reduce fan noise and improve cooling efficiency without requiring additional parts and increasing the number of manufacturing steps.

[0008]

SUMMARY OF THE INVENTION An axial fan mounting structure according to the present invention is an axial fan mounting structure in which an axial fan is mounted on a mounting surface of an inner surface of a housing so that a wind direction can flow inside the housing. A spacer having a predetermined height is provided around the mounting screw between the surface and the axial fan.

According to the present invention, since the spacer having the predetermined height is provided around the mounting screw between the mounting surface and the axial fan, the predetermined space is provided between the mounting surface and the axial fan. Therefore, fan noise can be reduced and cooling efficiency can be improved without requiring additional parts and increasing the number of manufacturing steps.

[0010]

BEST MODE FOR CARRYING OUT THE INVENTION An embodiment of an axial flow fan mounting structure of the present invention will be described below with reference to FIGS. In this embodiment, for example, as shown in FIG. 3, in order to radiate the heat inside the electric device 1 such as a switching power supply, the mounting surface of the electric device 1 inside the housing, for example, the front plate 1a.
The axial fan 2 is attached to the inner surface of the so that the wind direction flows inside the housing.

In this example, the front plate 1a of the housing of the electric device 1 is, for example, a metal plate of iron, aluminum, stainless steel or the like having a thickness of about 0.8 mm to 3 mm, and in this example, a metal plate having a thickness of 2 mm. The front plate 1a is provided with an axial fan mounting portion having a plurality of square holes for forming air holes.

The air holes may have a plurality of round holes or slits as shown in FIGS. 9 and 10.

In the present embodiment, the burring holes 1b are formed on the front plate 1a at four positions corresponding to the mounting holes formed in the axial fan 2 of the front plate 1a so as to project inward by press working or the like. 1b, 1b, 1b are provided.

As shown in FIGS. 4A and 4B, the burring hole 1b is formed by squeezing or punching a cylindrical shape 1c on a flat plate, and the plate thickness of the flat plate is partially increased pseudo. .

In this example, the height h of the cylindrical shape 1c of the burring hole 1b is set to 3 mm. The height of the cylindrical shape 1c may be in the range of 1 mm to 5 mm, but in view of reduction of fan noise described later, data of wind speed flowing inside the housing, and ease of forming the burring hole 1b, this height h is 3 mm is the most desirable dimension.

In this embodiment, a tapping screw is provided on the inner surface of the front plate 1a of the housing of the electric device 1 as shown in FIGS. 1 and 2 through the four burring holes 1b of the front plate 1a. At 3 from the outside of the front plate 1a of the housing, it is directly driven into the mounting hole of the axial fan 2 so as to tighten the front plate 1a together, and the axial fan 2 is mounted inside the front plate 1a.

In this case, the burring hole 1b of the front plate 1a
The cylindrical shape 1c of this is the inner surface of the front plate 1a and the axial fan 2
To form a spacer, and the space between them is, for example, 3 mm.

Further, in this example, a portion C corresponding to the hole base of the burring hole 1b as shown in FIG. 4B is provided so that the screw head of the mounting screw 3 on the outside of the front plate 1a of the housing of the electric device 1 does not project. The surface is provided and the countersunk tapping screw 3 is used. The size of the C surface is determined by the shape of the countersunk head of the tapping screw 3.

According to this embodiment, as described above, a spacer or burring hole 1b having a predetermined height, for example 3 mm, is provided around the mounting screw 3 between the inner surface of the front plate 1a of the housing of the electric device 1 and the axial fan 2. Since the cylindrical shape 1c is arranged, a predetermined gap, for example, 3 mm can be formed between the inner surface of the front plate 1a and the axial fan 2, and the number of manufacturing steps can be increased without requiring additional parts. In addition, the wind speed can be relatively increased, the cooling efficiency can be improved, and the fan noise can be reduced.

Incidentally, as shown in FIG. 11, a conventional product in which this axial fan 2 is directly attached to the inner surface of the front plate 1a of the housing, and a front plate 1a of the housing and the axial fan 2 as shown in FIG. A square frame 4 is provided between them, and the thickness of this frame 4 is 3 m.
The fan noise amount and the measurement point A between Comparative Examples 1 and 2 of m and 5 mm and Examples 1 and 2 in which the cylindrical shape 1c of the burring hole 1b of the front plate 1a, that is, the height h of the spacer is 3 mm and 5 mm, The wind speeds in B and C are shown in Table 1 and Table 2.
It was as shown in. The rating of this axial fan 2 is 12V
DC, 0.77A, voltage at the time of measurement is 12VDC,
The current was 0.7A.

[0021]

[Table 1]

The fan noise amount in Table 1 is measured at a position 1 m away from the noise measuring device in the listening room.

[0023]

[Table 2]

The fixed point A in Table 2 is 100 mm from the front plate 1a inside the housing of the electric device 1 and has a height of 80 mm and 60 mm from the right side. The fixed point B is 150 mm from the front plate 1a and 80 mm from the right side. 60 mm, measurement point C is front plate 1
200 mm from a, height 80 mm, 60 mm from right side
Is.

From Table 1, it is clear that the fan noise amount in Examples 1 and 2 is reduced as compared with the conventional product, and from Table 2 in Examples 1 and 2, electric equipment is used. It can be seen that the wind speed inside the housing of No. 1 is faster than that of the conventional product and Comparative Examples 1 and 2, and the cooling efficiency is improved.

FIGS. 5, 6, 7 and 8 show another example of the embodiment of the present invention. 5, FIG. 6, FIG. 7 and FIG. 8, parts corresponding to those in FIG. 1 and FIG. 2 will be assigned the same reference numerals and detailed description thereof will be omitted.

In the examples of FIGS. 5 and 6, the mounting screw 3 composed of the tapping screw of the examples of FIGS. 1 and 2 is attached to the axial fan 2.
Is used as a mounting screw 10 that penetrates through, and the hexagonal nut 10a is tightened to fix the axial fan 2 to the inside of the front plate 1a of the housing of the electric device 1. Others are the same as those in FIGS. 1 and 2.

It can be easily understood that the same effects as those of the examples of FIGS. 1 and 2 can be obtained in the examples of FIGS. 5 and 6 as well.

In the example of FIG. 7, the burring holes 1b are not formed in the front plate 1a in the examples of FIGS. 5 and 6, but only the through holes 1d are formed in the front plate 1a, and the inner surface of the front plate 1a and the axial fan are formed. The axial screw 2 is attached to the front plate 1a such that the cylindrical screw 11 having a predetermined height is provided through the mounting screw 10 between the two mounting holes and the nut 10a is tightened together. Others are shown in FIG.
The configuration is similar to that of FIG.

In the example of FIG. 7 as well, the cylindrical spacer 11 having a predetermined height is arranged around the mounting screw 10 between the inner surface of the front plate 1a of the housing of the electric device 1 and the axial fan 2. It can be easily understood that a predetermined space can be provided between the inner surface of the front plate 1a and the axial fan 2, and the same operational effect as the above example can be obtained.

In the example shown in FIG. 8, the mounting screw is constituted by an embedding screw 13 provided on the inner surface of the front plate 1a of the housing of the electric device 1, and the embedding portion 13a of the embedding screw 13 by caulking or the like is set to a predetermined height, and this embedding is performed. The axial fan 2 is attached by tightening the nut 13b with the screw 13. Others are the same as those in the examples of FIGS. 1 and 2.

In this case, the front plate 1a of the housing of the electric device 1
Since the embedded portion 13a is arranged between the inner surface of the axial fan 2 and the inner surface of the axial fan 2, a predetermined gap can be formed between the inner surface of the front plate 1a and the axial fan 2, and the same effect as the above example can be obtained. It's easy to see what you get.

The present invention is not limited to the above-mentioned examples, and it goes without saying that various other structures can be adopted.

[0034]

According to the present invention, since a spacer having a predetermined height is provided around the mounting screw between the mounting surface and the axial fan, a predetermined gap is provided between the mounting surface and the axial fan. Therefore, fan noise can be reduced and cooling efficiency can be improved without requiring additional parts and increasing the number of manufacturing steps.

[Brief description of drawings]

FIG. 1 is an exploded perspective view showing an example of an embodiment of a mounting structure for an axial fan according to the present invention.

FIG. 2 is a side view of the example of FIG.

FIG. 3 is a perspective view showing an example of an electric device.

4A and 4B show examples of burring holes, FIG. 4A is a perspective view, and FIG. 4B is a sectional view taken along line BB in FIG.

FIG. 5 is an exploded perspective view showing another example of the embodiment of the present invention.

FIG. 6 is a side view of the example of FIG.

FIG. 7 is an exploded perspective view showing another example of the embodiment of the present invention.

FIG. 8 is an exploded perspective view showing another example of the embodiment of the present invention.

FIG. 9 is a plan view showing an example of a front plate.

FIG. 10 is a plan view showing an example of a front plate.

FIG. 11 is a side view showing an example of a conventional attachment structure of an axial fan.

FIG. 12 is an exploded perspective view showing an example of a conventional attachment structure of an axial fan.

[Explanation of symbols]

1 ... Electrical equipment, 1a ... Front plate, 1b ... Burring hole, 1c ... Cylindrical shape, 2 ... Axial fan, 3, 10 ...
Mounting screws, 10a, 13b Nuts, 13
Embedded screw, 13a ... Embedded part

Claims (4)

[Claims] 1. A mounting structure of an axial fan in which an axial fan is mounted on a mounting surface of an inner surface of a housing so that a wind direction flows inside the housing, and a mounting screw between the mounting surface and the axial fan is attached. An axial-flow fan mounting structure, characterized in that a spacer having a predetermined height is provided around the periphery. 2. The mounting structure for an axial fan according to claim 1, wherein a spacer having a predetermined height around the mounting screw is formed of a burring hole. 3. The mounting structure for an axial fan according to claim 1, wherein a spacer having a predetermined height around the mounting screw is formed by an embedded portion of an embedded screw. Mounting structure. 4. The mounting structure for an axial fan according to claim 1, wherein the spacer has a height of 1 mm to 5 mm.