JPH11107996A - Dc brushless axial flow heat sink fan motor - Google Patents

Abstract

PROBLEM TO BE SOLVED: To improve the radiating characteristic by arranging a coreless stator armature opposed to a field magnet provided on an axial flow rotating blade within a recessed part having a closed inner bottom so as to take air from the upper end part and discharge the air from the opening end. SOLUTION: A bearing housing 6 has an engaging stepped part 25 for positioning an iron base plate 11 on the circumferential part. A careless stator armature 13 is formed by insulating the upper surface of the base plate 11 and providing a plurality of air-core type armature coil 12-1, 12-2 groups set in single phase current-carrying arrangement, and face-opposed to a field magnet 14 provided on a rotary blade 2 through an axial clearance, to relatively rotate it. When the rotary blade 2 is rotated, the air taken from the axial direction is efficiently circulated within the fan motor body 1 to improve the radiating characteristic. Thus, satisfactory radiating characteristic can be provided with a thin and small size.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention
The present invention relates to a DC brushless axial heat sink fan motor used for cooling a switching power supply, electronic equipment, and the like. In this case, the axial fan motor is designed to draw in wind from the axial direction and guide the wind further to the bottom below the wind.
Further, it is a DC brushless axial flow heat sink fan motor such as a radial flow fan motor for flowing sucked air in a direction perpendicular thereto.

[0002]

2. Description of the Related Art In recent electronic devices, miniaturization has been promoted and high-density mounting has tended to occur. Therefore, diffusion of heat generated inside the devices has become an important issue. As a means for solving such a problem, a DC brushless axial fan motor is frequently used. In such a DC brushless axial fan motor, in order to improve the heat radiation characteristics, a screw 36 or the like is conventionally provided on a heat sink 32 having a large number of heat radiation pins 19 formed of aluminum or the like as shown in FIG. The DC brushless axial fan motor 34 is used to fix the DC brushless axial fan motor 34, and the DC brushless axial fan motor 34 sends the wind to the heat sink 32, thereby improving the heat radiation characteristics.

[0003] However, in recent electronic devices, although the density is high, the devices themselves tend to be downsized, and the heat sink and the fan motor tend to be integrated to be downsized. For example, as shown in a DC brushless axial flow heat sink fan motor 3 'as shown in FIG.

[0004]

The DC brushless axial heat sink fan motor 3 'shown in FIG. 7 has a great advantage because the heat sink 32 and the DC brushless axial fan motor 34 are integrated.

However, the DC brushless axial flow heat sink fan motor 3 'is formed by concentrically forming a plurality of heat radiation fins 37 protruding in the concave portion 5' of the heat sink fan motor main body 1 'in a ring shape. The axial flow rotating blades 2 ′ are configured to rotate on them, and air is passed through the passage 38 between the radiation fins 37 formed concentrically in an annular shape, and then formed on one side. The air is discharged to the outside through the open end.

[0006] According to such a DC brushless axial flow heat sink fan motor 3 ', the thickness of the rotary blade 2' can be formed only thinly, and the through hole 2 formed in the upper lid 21 'is formed.
There is a disadvantage that the amount of air taken into the recess 5 'through the 0' is small, and the heat radiation characteristics are poor.

In the radiation fin 37 having the above-described shape, the air introduced into the concave portion 2 'simply passes through the passage 38 smoothly, and has low air resistance and poor heat radiation characteristics. 'There is a drawback.

That is, in the conventional DC brushless axial heat sink fan motor 3 ', the motor portion cannot be made large and the rotary blade 2' structure which can take in a large amount of air into the concave portion 5 'is not provided. In addition, in order to improve the heat radiation characteristics, the entire thickness must be increased, and there is a disadvantage that the thickness becomes large.

[0009] That is, an object of the present invention is to obtain a DC brushless axial heat sink fan motor 3 which has a small thickness as a whole, is small in size, takes in a large amount of air, and has very good heat radiation characteristics. It was done in.

[0010]

SUMMARY OF THE INVENTION The object of the present invention is to close three sides 22-1,..., 22-3 and to make only one side an open end 23, The radiation fins 4 are integrally formed at the ends 23, and the heat sink fan motor main body 1 has a recess 5 in which an inner bottom 24 is closed so as to take in air from the upper end and discharge air from the open end 23. In a DC brushless axial heat sink motor in which an axial flow type rotary blade 2 is rotatably supported,
Radiation fins 4 are formed at the opening end 23 by adjusting the direction of rotation of the rotary blade 2 at an angle at which the wind by the axial flow type rotary blade 2 easily flows, and forming the radiation fins 4 at the open end 23. An air intake 41 communicating with the concave portion 5 is provided at the final end in the rotation direction, and the radiation fins 8-8 are provided between the outer periphery of the rotary blade 2 and the three sides 22-1,. .., 8-3, and the radiation fins 8
-1,..., 8-3 group and the above three side sides 22-1,.
.., the radiation fins 8-1,.
-3 is formed by forming a passage 9 for the air passing therethrough, and arranging a coreless stator armature 13 in the recess 5 facing the field magnet 14 provided on the axial-flow type rotary blade 2.

(Operation) When the axial flow type rotary blade 2 rotates,
Air is taken into the recess 5 through the through hole 20. On the other hand, air is taken into the recess 5 from the air intake 41 through the heat radiation fins 8-1. These recesses 5
The air taken in flows through the radiating fins 8-2 into the air passage 9 and also passes through the inside of the side 22-2 and the air passage 9 on the inside of the side 22-3 and dissipates heat. The air passage 9 while being cooled through the fins 8-3
Then, while being further dissipated by the heat dissipating fins 4, the heat is dissipated and discharged from the slit 39 between the heat dissipating fins 4 at the opening end 23. That is, the cooled air is discharged from the slit 39, and efficiently cools the target object to be cooled.

[0008]

DESCRIPTION OF THE PREFERRED EMBODIMENTS

FIG. 1 is an exploded perspective view of a DC brushless axial heat sink fan motor 3 of the present invention, FIG. 2 is a longitudinal sectional view of the DC brushless axial heat sink fan motor 3, and FIG. FIG. 4 is a plan view of a heat sink fan motor main body 1, and FIG. 5 is a plan view of a heat sink fan motor main body 1 'showing another embodiment. Hereinafter, an embodiment of a DC brushless axial heat sink fan motor 3 according to the present invention will be described with reference to FIGS.

The heat sink fan motor body 1 has a flat rectangular shape formed of a metal having excellent thermal conductivity such as aluminum or an aluminum alloy, and has three sides 22-.
,..., 22-3 are closed, and only one side is an open end 23, and the heat radiation fins 4 are formed integrally with the open end 23.

The upper end of the heat sink fan motor main body 1 is an open end so that air can be taken in from the upper end, and the upper end has a central portion having the same shape as the heat sink fan motor main body 1. The heat sink fan is formed by using a screw 21 formed in a corner flange 33 of the heat sink fan motor body 1 through a through hole 28 formed in the cover 21 by using a cover 21 having a through hole 20 in the portion. The upper end of the motor body 1 is closed.

[0011] The heat sink fan motor main body 1 comprises:
The inner bottom 24 has a recess 5 in which the inner bottom 24 is closed so as to discharge air from the slit 39 of the opening end 23.

The shaft 10 provided on the axial flow type rotary blade 2 by the sliding bearing 42 provided on the bearing housing 6 integrally formed in the concave portion 5 of the heat sink fan motor body 1 and the ball bearing 7 provided on the upper end thereof. By rotatably bearing, the axial-flow type rotary blade 2 is rotatably supported and housed in the recess 5.

On the outer periphery of the bearing housing 6, an iron substrate 1
1 is provided, the iron substrate 11 is positioned on the engaging step 25, the upper surface of the substrate 11 is insulated, and a plurality of air cores are placed in a single-phase energized arrangement. Coreless stator armature 13 is formed by providing a group of armature coils 12-1 and 12-2, and is opposed to a field magnet 14 provided on the rotating blade 2 via an air gap in the axial direction. Moving.

The heat sink fan motor body 1 is mounted on the upper surface of a column 15 protruding upward from the bottom of the motor body 1 and is formed through a through hole 43 provided in the iron substrate 11 positioned at the engaging step. The substrate 11 is fixed by screwing in a magnetic screw 16 for obtaining reluctance torque, whereby the coreless stator armature 13 having a single-phase energizing arrangement is formed on the fixed side.

The fins of the rotary blade 2 are integrally formed on the outer periphery of a cup body 17 made of a magnetic material such as an iron material so that the coefficient of thermal expansion is lower than that of the fan motor body 1.
Since the cup body 17 also serves as a rotor yoke, the field magnet 14 having N and S magnetic poles of circular 2P (P is an integer of 2 or more) poles is fixed below the cup body 17, and the above-described field magnet is provided through an axial gap. It faces the stator armature 13.

In the DC brushless axial heat sink fan motor 3, as shown in FIGS. 1 and 3, the heat sink fan motor body 1 has three outer peripheral sides (closed sides: 22-1,..., 22). -3) is closed, and it has an open end 23 which is open only on one side, and its inner bottom 24 is closed. The air is exhausted to the outside at right angles only from the open end 23 of the fan motor main body 1 made of aluminum also serving as a heat sink.

A bearing housing 6 having an engaging step 25 is formed integrally with a center portion of an inner bottom 24 of the fan motor main body 1, and a threaded support post 15 is formed integrally with an inner peripheral portion. However, the height of the column 15 is formed to be the same as the height of the engaging step 25. Further, a lead wire guide groove 26 extending from the bearing housing 6 to the closed side 22-1, passing through the lead wire 18 and leading out of the fan motor main body 1 is formed integrally with the inner bottom 24.

Inner peripheral portion and open end 2 of fan motor main body 1
The three parts include radiation fins 8-appropriately designed to improve the heat radiation characteristics when the rotary blade 2 rotates.
, 8-3 and the radiation fins 4 are integrally formed. The reason is that when the rotating blades 2 rotate, the air introduced into the fan motor main body 1 from the axial direction efficiently turns around to improve the heat radiation characteristics. A part of the radiating fins 8-1,..., 8-3 and a part of the radiating fins 4 are formed to be held down lower than the height of the fan motor main body 1.

The radiating fin 4 formed at the opening end 23
When the rotating blades 2 are rotated, the rotating blades 2 are further radiated so that they can be efficiently discharged to the outside through the slits 39.
The angle is formed in a direction along the rotation direction of.

The outer periphery of the rotary blade 2 and the three side edges 2
Radiation fins 8-1, 2-1,...
.., 8-3 group, and the radiation fins 8-1,.
8-3 group and the above three sides 22-1,..., 22-3
An air passage 9 is formed between the heat radiation fins 8-1,..., 8-3.

An air intake 41 communicating with the recess 5 is formed at the last end of the open end 23 in the rotation direction of the axial flow type rotary blade 2. This air intake 4
In the final interior of 1, a regulating ridge 44 is formed in the heat sink fan main body 1 so that the air that has passed through the air intake 41 flows through the radiating fins 8-1 into the recess 5.

Since the air inlet 41 is provided and the radiating fins 8-1 are provided, only the corner flange 33 'provided in the vicinity thereof is not provided at the corner unlike the other corner flanges 33, and is slightly provided on the radiating fin 4 side. It is formed so as to be biased. Therefore, one of the through holes 28 provided in the lid 21 is provided with the screw holes 31 formed in the corner flange 33 '.
Is formed at a location opposed to.

Therefore, when the rotary blades 2 rotate, the heat dissipating fins 8-1 are formed integrally with the main body 1 in an angular direction in which air flows into the recess 5 through the air intake 41.

The radiating fins 8-2 formed over the other end of the side 22-1 and one end of the side 22-2 are provided with the rotating blades 2 in the direction of the air passage 9 inside the side 22-1. The angle of the heat dissipating fins 8-2 is formed so that the air flows by the rotation of the fins, and is integrated with the main body 1.

The radiating fins 8-3 formed over the other end of the side 22-2 and the one end of the side 22-3 are provided with air flowing through the air passage 9 inside the side 22-2. The angle of the radiating fins 8-3 is formed so that the air flows through the air passage 9 inside the side 22-3 by the rotation of the rotary blade 2, and is integrated with the main body 1.

Therefore, when the rotary blade 2 rotates, the through holes 2
The air flows into the recess 5 through the air inlet 0 and the air enters the recess 5 through the air intake 41 and the radiating fins 8-1 group. The air that has entered the recess 5 is passed through the heat radiation fins 8-2 and 8-3 to the air passage 9 inside the sides 22-2 and 22-3, or directly into the slit 39.
It is released from the open end 23 through the group.

The reason for this is that when the rotating blades 2 rotate, they tend to float upward. However, if a failure occurs in the portion for preventing the lifting, or if the rotating blades 2 rotate at high speed, they will scatter. This is to prevent dangerous accidents, but there are other purposes as described below.

When the rotary blade 2 rotates, the upper end portion of the rotary blade 2 comes into contact with the lid 21, generating a loud sliding noise or stopping the rotation of the rotary blade 2 by lifting the rotary blade 2. There is a risk of being forced to do so.

Therefore, in the rotary blade 2, a notch 35 is formed at the upper end of the rotary blade 2 in order to avoid the above danger, and sliding contact between the upper end of the rotary blade 2 and the lid 21 is avoided. Like that.

Even if the notch 35 is formed as described above, the radius of the rotary blade 2 can be made as long as possible as a whole, so that the amount of air taken into the rotary blade 2 from above in the axial direction is reduced only slightly.

However, even if the notch portion 35 is formed, the air volume does not decrease, and the wind pressure increases. On the contrary, good results are obtained. In this regard, since a patent has already been filed, a description of the application will be left to the public, and a description thereof will be omitted here.

FIG. 5 shows a heat sink fan motor main body 1 'of a DC brushless axial heat sink fan motor showing another embodiment. In the main body 1 ′, the radiation fins 8-
The inner bottom 24 in the recess 5 between the outer circumference of the bearing housing 6 and the inner circumference of the first, second, third and eighth groups and the radiation fin 4 group,
A plurality of smooth bowl-shaped heat dissipation recesses 27 are formed concentrically with the bearing housing 6. The number of the concave portions 27 formed in an annular shape is appropriately determined by design according to the size of the fan motor main body 1 ′, and the number of the concave portions 27 formed in the annular concentric shape is also determined by the fan motor main body 1 ′. It is determined by design as appropriate according to the size of '. Forming such a concave portion 27 has an advantage that a large heat radiation effect can be obtained as compared with a case where it is not formed.

[0033]

According to the DC brushless axial-flow heat sink fan motor of the present invention, it is possible to obtain a fan having a very good heat radiation characteristic by taking in a large amount of air while having a small thickness and small size as a whole.

[Brief description of the drawings]

FIG. 1 is an exploded perspective view of a DC brushless axial flow heat sink fan motor of the present invention.

FIG. 2 is a vertical sectional view of the DC brushless axial flow heat sink fan motor.

FIG. 3 is an external perspective view of the heat sink fan motor.

FIG. 4 is a plan view of a heat sink fan motor main body.

FIG. 5 is a plan view of a heat sink fan motor main body showing another embodiment.

FIG. 6 is an explanatory diagram in a case where cooling is performed using a conventional heat sink and an axial fan motor.

FIG. 7 is an explanatory diagram of a conventional dc brushless axial flow heat sink fan motor.

[Explanation of symbols]

1, 1 'heat sink fan motor main body 2, 2' axial flow type rotating blade 3, 3 'DC brushless axial flow heat sink fan motor 4 radiating fin 5 concave portion 6 bearing housing 7 ball bearing 8-1, ..., 8-3 Radiation fin 9 Air passage 10 Shaft 11 Iron substrate 12-1, 12-2 Armature coil 13 Coreless stator armature 14 Field magnet 15 Support 16 Magnetic screw 17 Cup body 18 Lead wire 19 Heat radiation pin 20, 20 'transparent Hole 21, 21 ′ Lid 22-1,..., 22-3, 23 Side 23 Open end 24 Inner bottom 25 Engagement step 26 Lead wire guide groove 27 Heat radiating recess 28, 29 Through hole 30, 31 Screw Hole 32 Heat sink 33, 33 'Corner flange 34 DC brushless axial fan motor 35 Notch 36 Screw 37 Radiation fin 38 Passage 39 Slit 40 Screw 41 Air intake 42 Sliding bearing 43 Through hole 44 Regulatory ridge

Claims (1)

[Claims] 1. Three sides (22-1,..., 22-)
3) is closed, and only one side is an open end (23), and a radiation fin (4) is integrally formed with the open end (23), and air is taken in from the upper end to open from the open end (23). An axial-flow type rotary blade (2) is rotatably mounted in the concave portion (5) of the heat sink fan motor body (1) having a concave portion (5) with an inner bottom (24) closed so as to discharge air. DC brushless axial heat sink motor, comprising:
C brushless axial flow heat sink fan motor. A radiation fin (4) is formed at the opening end (23) so as to be oriented in the rotation direction of the rotary blade (2) at an angle at which the wind by the axial flow type rotary blade (2) flows easily. An air inlet (41) communicating with the recess (5) is provided at the final end of the open end (23) in the rotation direction of the axial flow type rotary blade (2). The outer periphery of the rotary blade (2) and the three side edges (22
-1,..., 22-3) between the radiating fins (8-1,
.., 8-3) group, and the radiation fins (8-1,.
.., 8-3) group and the above three sides (22-1,...)
., 22-3) between the radiation fins (8-1,.
8-3) The passage (9) for the air passing through the group is formed. A coreless stator armature (13) facing the field magnet (14) provided on the axial-flow rotary blade (2) is arranged in the recess (5).