JPH08289504A - Axial-flow cooling fan for electronic apparatus - Google Patents

Abstract

PURPOSE: To perform the cooling of an electronic apparatus efficiently by changing the air flow generated by a centrifugal-blower type impeller into the axial direction of a cooling fan in an axial air flowing chamber, and discharging the air. CONSTITUTION: A cooling fan 1 comprises a housing 2, a centrifugal blower type impeller 3 and an outer-rotor type motor 4. When the fan is used for sending air to an electronic apparatus having integrated circuits, a bolt is inserted into an attaching hole 6b, and a corner part 6a of an air-intake-side end plate 6 is attached to the surrounding part of the attaching hole of an air apparatus. When a motor 10 is operated and the impeller 3 is rotated, air is taken in through an air hole 5, pressure is made high by a blade 14 and the air is sent into the side of radial direction of the impeller 3. The air is sent into the axial direction of the housing 2 in an axial. air blowing chamber 19 around the impeller 3 and sent to the air discharging side. The air is discharged through an air-flow discharging hole 8. As a result, the high-pressure air flow is generated, and the electronic apparatus can be effectively cooled.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an axial cooling fan for cooling electronic equipment, and more particularly to an axial cooling fan for cooling highly integrated electronic equipment with high performance.

[0002]

2. Description of the Related Art A conventional axial cooling fan for electronic equipment was originally developed to cool electronic equipment having an electronic tube such as a vacuum tube installed therein, and its impeller is designed to cool air in the axial direction of the cooling fan. Composed of propeller-shaped blades for sending to. The design of this conventional cooling fan is
It must be designed to provide the required airflow to cool the electronics and must generate the required air pressure. However, in such an electron tube type electronic device, since the distance between the internal electronic elements is large and the air flow passage is large, a sufficient air volume can be obtained even if the air pressure is small, so that the air pressure measures are secondary. It was a thing.

Next, even when semiconductor elements have been adopted in electronic equipment, since there is a sufficient space between the mounted electronic elements, a conventional propeller-type axial cooling fan can obtain a required air volume. It was

However, as integrated circuits have been used for electronic elements, and as they have been highly integrated, the distance between electronic elements in electronic equipment has become extremely small, and the path between them has become narrow, resulting in a normal state. Then, there is a problem that air cannot be sufficiently passed. In order to sufficiently pass the air through such a narrow passage, a high air pressure may be generated by the cooling fan. Therefore, in the conventional cooling fan, the space between the outer circumference of the propeller blade and the inner peripheral surface of the fan housing may be reduced to reduce the amount of air flowing backward through this space. Due to the restriction on the shape of the outer peripheral surface, there was a limit to making this interval as small as necessary, and a sufficient wind pressure could not be obtained.

[0005]

SUMMARY OF THE INVENTION An object of the present invention is to use a ring-shaped centrifugal blower type impeller as an impeller and to make an air flow passing through a cooling fan into an axial flow. It is an object of the present invention to provide an axial cooling fan for electronic equipment, which can efficiently cool the equipment with a high air pressure and a required air volume.

[0006]

In order to solve this problem, an axial flow cooling fan for electronic equipment according to the present invention is an outer rotor type electric motor and a ring whose central portion is fixed to the rotor of the electric motor. -Shaped centrifugal blower type impeller, a body having a cylindrical inner peripheral surface and coaxially arranged on the impeller, and an intake hole provided on the intake end side of the body Along with the intake side end plate that covers the outer peripheral portion of the intake side end surface of the impeller in close proximity to it, a hollow cylindrical shape formed between the cylindrical inner peripheral surface of the body and the outer periphery of the impeller A housing provided with an air flow axialization chamber, and an air discharge side end plate having an air discharge hole communicating with the air flow axial flow chamber in an outer peripheral portion and having a stator of the electric motor fixed to a central portion thereof; Electronic device provided in the housing and to be cooled It constituted by including an attachment mechanism for securing the axial flow cooling fan electronics.

[0007]

According to the present invention, the intake side or air discharge side end plate portion of the axial cooling fan for electronic equipment of the present invention is fixed to the mounting hole portion of the electronic equipment while the cooling fan is accommodated in the electronic equipment. When activated, a positive or negative high wind pressure is generated in the electronic device, a wind flow of a desired size is generated in an extremely narrow space between highly integrated electronic elements, and these electronic elements are effective. Cool.

[0008]

Embodiments of the axial cooling fan for electronic equipment according to the present invention will be described below with reference to the drawings.

1 to 4 show an embodiment of an axial cooling fan (hereinafter simply referred to as "cooling fan") of the present invention. The cooling fan 1 includes a housing 2 and a centrifugal blower type impeller (hereinafter,
(Hereinafter simply referred to as "impeller") 3 and an outer rotor type electric motor 4 which supports and rotates the central portion thereof.

The housing 2 has a cylindrical body 4 having a cylindrical inner peripheral surface 4a, and a ring-shaped intake side having a circular intake hole 5 formed at one end of the body 4. The end plate 6 is fixed. Further, a disk-shaped air discharge side end plate 7 is formed at the other end of the body portion 4, and fan-shaped air discharge holes 8 are formed on the outer peripheral portion thereof by a support web 9 extending in the radial direction so as to be circumferentially spaced. Are placed. As shown in FIGS. 2 to 4, both end plates 6 and 7 are formed in a square shape, and a corner portion (projection) 6a protruding outward from the body portion 4 in the radial direction is formed.
Mounting holes 6b and 7b are formed in each 7a. Therefore, the cooling fan of this embodiment is of a rectangular type.

An outer rotor type electric motor 10 is provided in the center of the housing 2, and a stator 22 of the outer rotor type electric motor 10 is fixed to the center of the inner surface of the air discharge side end plate 7.
A rotor 11 is provided around the circumference of 2.

The impeller 3 is also a disk-shaped end plate 1 on the air discharge side.
2 has a boss portion 13 that extends toward the intake side and is fitted and fixed to the rotor 11 of the electric motor 10 at the center thereof, and has a plurality of blades extending from the outer peripheral portion of the inner surface of the end plate 12 toward the intake side. 14 is projected. As shown in the upper side of FIG. 1, a ring-shaped intake side end plate 20 is provided at the intake end of the blade 14.
Is provided. The inner diameter of the end plate 20 is the same as or slightly smaller than the diameter of the intake hole 5 of the housing 2. Further, the end plate 20 is formed so that the outer surface thereof is extremely close to the inner surface of the intake side end plate 6 of the housing 2, and air between the both surfaces is suppressed as much as possible toward the intake hole. Further, as shown in the lower side of FIG. 1, a circular rim 21 may be provided instead of the end plate 20 in order to reinforce the outer peripheral portion of the intake side end of the blade 14.

As shown in FIG. 4, these blades 14 are arranged at equal intervals in the circumferential direction of the end plate 12, and their outer ends and inner ends are cylindrical outer peripheral surface 15 and cylindrical shape, respectively. The inner peripheral surface 16 is defined, and the diameter of the outer peripheral surface 15 is equal to the outer diameter of the air side end plate 20. These blades 14 are inclined from the outer peripheral surface 15 toward the inner peripheral surface 16 in the rotation direction R of the impeller 3, and at the same time, preferably, the spiral winding which is convexly curved in the rotation direction R (for example,
Part of the ellipse). The shape of this blade 14 is
An appropriate one is selected according to the size of the impeller 14, the size / inclination angle / number of the blades, the desired air pressure, the desired air volume, etc.,
When the wind pressure generating performance may be slightly lowered, each blade 14 may be formed of a flat plate as shown in the lower side of FIG.

A ring-shaped air flow axial flow conversion chamber 19 is formed between the outer peripheral surface 15 of the impeller 3 and the cylindrical inner peripheral surface 4a of the body 4 coaxial therewith, and this is an air discharge side. End plate 7
It is adapted to communicate with the air discharge hole 8 of. In addition, a rim portion 6c having a triangular cross section is formed on the outer peripheral portion of the inner surface of the intake side end plate 6 to restrict air from flowing into the space between the intake side end plates 6 and 20 from the air flow axialization chamber 19. ing.

FIG. 5 shows the air pressure-air flow characteristic curves 17 and 18 of the axial cooling fan of the present invention equipped with a centrifugal blower type impeller and the conventional axial flow cooling fan equipped with a propeller type impeller, respectively, as solid lines. Is indicated by a dotted line. Both impellers have the same dimensions. The units of wind pressure and air volume are usually expressed in millimeters (water column) and cubic meters / minute, respectively. From these characteristics, on the left side of the intersection A of both curves, the cooling fan of the present invention generates a larger wind pressure than the conventional cooling fan for the same air volume, and at the same operating point B, the cooling fan of the present invention. Is larger than the conventional cooling fan (about 2 in the example of FIG. 5).
You can see that the Therefore, it is apparent that the present invention can cool the electronic device with higher efficiency than ever before.

Next, the operation of the cooling fan 1 of this embodiment will be described.

When the cooling fan 1 is used for sending air to an electronic device having an electronic element having an integrated circuit, a bolt is passed through the mounting hole 6b and an air discharge side end plate 7 is provided.
With the inside facing, the corner 6a of the intake side end plate 6 is attached around the attachment hole of the electric device. When the cooling fan 1 draws air from the electronic device and discharges it out of the device, a bolt is passed through the mounting hole 7b so that the intake side end plate 6 is inside and the corner of the air discharge side end plate 7 is located. The portion 7a is attached around the attachment hole of the electric device. In any case, the cooling fan 1 is embedded in the electronic device so that it does not get out of the way by protruding outside the device.

When the electric motor 10 is operated to rotate the impeller 3 in the direction indicated by R in FIG. 4, air is taken in from the intake hole 5 while the blade 14 increases the pressure to a high pressure in accordance with the characteristics shown by the solid line in FIG. It is sent to the outside in the radial direction of 3. The air thus sent out is sent to the axial direction and the air discharge side of the housing 2 in the air flow axial flow chamber 19 around the impeller 3, and is discharged through the air discharge hole 8.

When the cooling fan 1 is used for intake air, it generates a high negative pressure in the equipment and the space between the electronic elements, that is,
Air can be passed through the air passage with a large amount of air to cool these electronic elements sufficiently, and when the cooling fan 1 sends air into an electronic device, a large positive wind pressure is generated in the device. As in the case where negative pressure is applied, the electronic device in the device can be sufficiently cooled.

FIG. 6 shows a second embodiment of the cooling fan of the present invention. The cooling fan 51 has the same structure and operation as the cooling fan of the first embodiment except for the mounting means.
The mounting means is constructed by forming mounting holes at the corners of the square end plates of the housing 2 in the first embodiment, but in the second embodiment, the intake side end of the outer peripheral surface of the cylindrical housing 52. And a plurality of substantially semicircular projections 73, 74 on the end of the air discharge side, which are spaced apart from each other in the circumferential direction of the housing 52 (in the case of the present embodiment, four projections are formed at equal intervals, respectively).
Individual pieces), and mounting holes 75 and 76 are formed in these. Outer rotor electric motor 60 and blade 6
4 is the outer rotor motor 1 of the first embodiment, respectively.
0 and blade 14.

In the first embodiment, the both end plates of the housing are square, but they may be other regular polygons or may be general polygons. Furthermore, in the second embodiment, the protrusions 73,
Although 74 has a semicircular shape, it may have another shape depending on the purpose of attachment. In addition, when the cooling fan is exclusively used for intake or air intake, the mounting means may be provided only on the air discharge side of the housing or only on the intake side of the housing.

[0022]

In the axial flow cooling fan for electronic equipment of the present invention, a centrifugal blower type is used as the impeller, and the air flow generated by this impeller is supplied to the cooling fan in the air flow axis conversion chamber. Since the air is discharged from the air discharge holes by changing it in the axial direction, a high-pressure air flow can be generated, and this air can be circulated in the axial direction of the cooling fan. There is an effect that it is possible to effectively cool the electronic device in which the electronic element of the electronic device is mounted.

[Brief description of drawings]

FIG. 1 is a vertical sectional view of a first embodiment of an axial cooling fan for electronic equipment according to the present invention.

FIG. 2 is a view of the cooling fan of FIG. 1 viewed from an intake side.

FIG. 3 is a view of the cooling fan of FIG. 1 viewed from the air discharge side.

FIG. 4 is a sectional view taken along line 5-5 in FIG.

FIG. 5 is an air pressure-air volume characteristic diagram of the cooling fan of the present invention and a conventional cooling fan.

FIG. 6 is a perspective view of an axial cooling fan for electronic equipment according to a second embodiment of the present invention as seen from the intake side.

[Explanation of symbols]

 1 Cooling Fan of First Embodiment 2 Housing 3 Impeller 4 Body 4a Inner Surface 5 Intake Hole 6 Intake End Plate 6a of Housing 6a Corner (Protrusion) 6b Mounting Hole 6c Rim Part 7 Air Discharge End Plate 7a of Housing Corner (protrusion) 7b Mounting hole 8 Air discharge hole 10 Outer rotor electric motor 11 Rotor 12 End plate on air discharge side of impeller 14 Blade 15 Outer peripheral surface 16 Inner peripheral surface 17 Wind pressure-air volume characteristic of the cooling fan of the present invention 18 Conventional Air Pressure-Air Volume Characteristics of Cooling Fan 19 Air Flow Axial Sulfurization Chamber 20 Impeller Intake Side End Plate 21 Rim 22 Stator 51 Second Embodiment Cooling Fan 52 Housing 60 Outer Rotor Motor 64 Blade 73 Protrusion 74 Protrusion 75 Mounting Hole 76 Mounting Hole R Impeller rotation direction B Operating point

Claims (7)

[Claims] 1. An axial flow cooling fan for electronic equipment, comprising: (1) an outer rotor type electric motor; and (2) a ring-shaped centrifugal blower type central portion fixed to the rotor of the electric motor. (3) An impeller, (3) a body having a cylindrical inner peripheral surface and coaxially arranged on the impeller, an intake end of the body and an intake hole, and an intake side of the impeller. An intake-side end plate that covers the outer peripheral portion of the end surface in close proximity thereto, and a hollow-cylindrical airflow axial flow chamber formed between the cylindrical inner peripheral surface of the body and the outer periphery of the impeller. A housing having an air discharge hole communicating with the air flow axial flow chamber in an outer peripheral portion and an air discharge side end plate having a stator of the electric motor fixed to a central portion, and (4) provided in the housing Axial cooling fan for electronic equipment Mounting means for securing the. 2. The impeller includes a disk-shaped air discharge side end plate whose central portion is fixed to the rotor of the electric motor, and an outer peripheral portion of an inner surface of the air discharge side end plate of the impeller. Blades spaced apart from each other, each of the blades having an air discharge side end of the impeller so that an intake side end of the blade approaches an inner surface of the intake side end of the housing. The axial flow cooling fan for an electronic device according to claim 1, wherein the axial flow cooling fan extends from the portion and is inclined from the outer side to the inner side in the rotation direction of the impeller. 3. A diameter of an inner peripheral surface of the blade, the outer diameter being equal to the diameter of the outer peripheral surface defined by the outer end of the blade, and the inner diameter being defined by the inner end surface of the blade. The axial flow cooling fan for electronic equipment according to claim 2, wherein the ring-shaped intake side end plate is formed. 4. The axial cooling fan for electronic equipment according to claim 2, wherein a circular rim for reinforcing the end of the blade is formed at the end on the intake side. 5. The blade according to claim 2, wherein the blade is curved in a convex shape in the rotation direction of the impeller.
An axial flow cooling fan for electronic equipment as described in. 6. The axial cooling fan for electronic equipment according to claim 1, wherein the blade is a flat plate. 7. The shaft for an electronic device according to claim 1, wherein the mounting means is a protrusion formed on at least one of both ends of the outer periphery of the housing and having a mounting hole. Flow cooling fan.