JP2000060066A - Fan motor - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a fan motor capable of being manufactured inexpensively and efficiently and with few defective parts, and attaining miniaturization, light-weight and slimming. SOLUTION: This fan motor 20 is provided with a stator 20B, having a coil 26 for forming a magnetic field and a rotor 20A in which a shaft 21 rotatably-held on the stator 20B is fixed to a rotor housing 22, wherein the rotor 20A is provided with a blade 24 which is integrally formed with the outer periphery side of the rotor housing 22 and rotates to generate wind, a magnet part 22a which is integrally formed with the rotor housing 22 and forms the magnetic field on the surface facing the stator 20B of the rotor housing 22, and a yoke 23 which is formed insertedly into the rotor housing 22 and forms a fixed magnetic path at a magnetic field generated by the magnetic part 22a.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an improvement in a fan motor, and more particularly, to a fan motor which can be manufactured inexpensively, efficiently and with less defective products, and which can be reduced in size, weight and thickness. Things.

[0002]

2. Description of the Related Art Conventionally, a fan motor having an integrated rotor and blades has been used to cool various electronic components of electronic equipment such as a personal computer. This fan motor has been reduced in size, weight and thickness. Is being promoted.
For example, Japanese Utility Model Laid-Open No. 1-58278, Japanese Utility Model Laid-Open No. 1-238
No. 449, Japanese Unexamined Patent Publication No. 5-122900, a blade portion on the rotor side of a fan motor,
Attempts have been made to downsize the fan motor by integrally molding the shaft and the like.

FIG. 4 is a cross-sectional view showing an example of a conventional fan motor disclosed in Japanese Utility Model Laid-Open No. 1-248449, and FIG. 5 is a front view showing the rotor in FIG. Next, the fan motor 1 will be described. The fan motor 1 shown in FIG. 4 includes a rotor 1A and a stator 1B. The rotor 1A shown in FIGS. 4 and 5 has a rotor housing 2, a yoke 3, blades 4, a magnet 5, a shaft 6, and the like. A shaft 6 is fixed to the center of the rotor housing 2 by press fitting, and a blade 4 is formed on the outer peripheral side. A yoke 3 made of an iron plate or the like is formed below the rotor housing 2, and the rotor housing 2, the yoke 3, and the blades 4 are integrally formed. Also,
A magnet 5 is fixed to the lower portion of the yoke 3 by bonding or inserting engagement.

The stator 1B shown in FIG. 4 includes a coil 7, a substrate 8, a yoke 9, a stator housing 10, and a bearing 1.
1, a stop ring 12 and the like. The substrate 8 is provided on a stator housing 10, and a yoke 9 is formed on the substrate 8. The coil 7 is on the yoke 9
Are arranged, and the coil 7 and the substrate 8 are electrically connected. A bearing 11 is arranged at the center of the stator housing 10, and the shaft 6 is inserted into the bearing 11. The retaining ring 12 is fixed to the shaft 6 so that the inserted shaft 6 does not move in the thrust direction SD.

[0005] An operation example of the fan motor 1 will be described with reference to FIGS. 4 and 5. First, a current is supplied to the substrate 8 from an external terminal, and the substrate 8 supplies the current to the coil 7. Then, the coil 7 generates a magnetic field, and the magnetic field forms a fixed magnetic path by the yoke 3 and the yoke 9. The rotor 1 </ b> A is rotated by the magnetic field and the magnet 5,
Generates wind.

FIG. 6 is a sectional view of a rotor in another example of a conventional fan motor disclosed in Japanese Patent Application Laid-Open No. 5-122900. The fan motor 13 will be described with reference to FIG. . The fan motor 13 in FIG. 6A has a rotor 13A and a stator 13B, and the rotor 13A in FIG.
5, a shaft 16 and the like, and the blade 14 and the magnet portion 15 are integrally formed. Also magnet part 1
A shaft 16 is fixed to 5 by press fitting. Feather 14
The magnet part 15 is made of, for example, a plastic magnet composition such as a ferrite-based or samarium-cobalt-based material. Oriented.

[0007]

However, FIG. 4 to FIG.
Has the following problems. First, in a fan motor 1 typified by Japanese Utility Model Laid-Open No. 1-238449 shown in FIGS. 4 and 5, the rotor housing 2, the yoke 3, and the blades 4 are integrally formed to form a bonding process when the fan motor 1 is manufactured. Therefore, the fan motor 1 is manufactured with high accuracy, and the fan motor 1 is downsized. However, when the magnet 5 is arranged below the yoke 3, a step of inserting and engaging must be performed, and there is a problem that the fan motor 1 cannot be manufactured efficiently. Further, by forming the magnet 5 as a separate member, the magnet 5
However, there is a problem that there is a risk of falling off.

[0008] Japanese Patent Laid-Open No. 5-122900 shown in FIG.
In the fan motor 13 of the publication, the blade portion 14 and the magnet portion 15 are integrally formed and the magnet portion 15 is made of a plastic magnet composition, so that the magnet does not fall off due to adhesion or the like, and efficient production and production of the rotor are achieved. Thinner,
Lightening is being attempted. However, JP-A-5-1229
In Patent Document No. 00, no yoke is formed, so that a constant magnetic path cannot be formed for a magnetic field generated by the coil. In order to prevent the magnetic field leakage of the magnet, the magnet portion is extremely anisotropic and is formed so as to be focused and oriented in the radial direction. However, there is a problem that the magnetic field leakage of the coil cannot be efficiently prevented.

Accordingly, an object of the present invention is to solve the above-mentioned problems, and to provide a fan motor that can be manufactured efficiently at low cost and with less defective products, and that can be reduced in size, weight and thickness. And

[0010]

According to the first aspect of the present invention, a stator having a coil for forming a magnetic field and a shaft rotatably held by the stator are fixed to a rotor housing. In the fan motor having a fixed rotor, the rotor is integrally formed on an outer peripheral side of the rotor housing, and faces a blade for rotating to generate wind, and a stator in the rotor housing. A magnet part formed integrally with the rotor housing to form a magnetic field, and a yoke formed insert-molded in the rotor housing to form a constant magnetic path in the magnetic field generated by the magnet part. This is achieved by a fan motor having:

According to the first aspect, the rotor has the magnet part, the yoke, and the blade integrally formed with the rotor housing. As a result, the rotor can be manufactured without the need for the bonding step, so that product errors due to the bonding step can be eliminated, and the assembling work can be made more efficient. In addition, since the magnet portion and the yoke are integrally formed, these components can be prevented from dropping from the rotor housing.

According to a second aspect of the present invention, in the configuration of the first aspect, the magnet portion is formed on each of an inner peripheral side and an outer peripheral side of the yoke so as not to fall off from the rotor housing. This is achieved by a fan motor in which a cylindrical yoke throttle portion is formed toward the surface on which the yoke is formed. According to the second aspect, by providing the yoke restricting portion, the coupling strength between the rotor housing and the rotor yoke can be improved.

According to a third aspect of the present invention, in the configuration of the first aspect, the magnet portion is formed by a fan motor in which S poles and N poles are alternately formed along the circumference. Achieved.

[0014]

Preferred embodiments of the present invention will be described below in detail with reference to the accompanying drawings. Note that the embodiment described below is a preferred specific example of the present invention,
Although various technically preferable limits are given, the scope of the present invention is not limited to these modes unless otherwise specified in the following description.

FIG. 1 is a sectional view showing a preferred embodiment of a fan motor of the present invention, and FIG. 2 is a top view showing a rotor 20A. The fan motor 20 will be described in detail with reference to FIGS. The fan motor 20 shown in FIG. 1 includes a rotor 20A and a stator 20B.
Represents a shaft 21, a rotor housing 22, a yoke 23,
It has a blade 24 and the like. The rotor housing 22 is made of, for example, a ferrite bond magnet, and the shaft 21 is press-fitted into the rotor housing 22 and fixed. A blade 24 is integrally formed on the side surface of the rotor housing 22. When the rotor 20A rotates, the blade 24
Generates wind.

A yoke 23 for forming a magnetic path with respect to a magnetic field generated from the magnet portion 22a is insert-molded on the upper portion of the rotor housing 22.
3 is made of, for example, galvanized steel. Yoke 23
Are formed at both ends thereof. The yoke throttle portions 23a and 23b sandwich the rotor housing 22 so that the yoke 23 does not fall off, and at the same time, prevent the yoke 23 from rotating with respect to the rotor housing 22. As shown in FIG. 2, the magnet portion 22 is provided on the surface of the rotor housing 22 facing the stator 20B.
a is formed, and the magnet 22a is formed along the circumference so that, for example, six S poles and N poles alternate.

Next, the stator 20B will be described in detail with reference to FIG. The stator 20B includes a stator housing 25, a coil 26, a substrate 27, a yoke 28, a shaft receiving portion 30, and the like. Stator housing 2
5, a substrate 27 is disposed, and the substrate 27 is electrically connected to an external terminal (not shown).
6 for supplying power. A yoke 28 is provided on the substrate 27, and the coil 26
Is arranged. The coil 26 generates a magnetic field when a current flows, and the yoke 28 forms a magnetic path for the generated magnetic field.

A through hole 25a is formed in the center of the stator housing 25, and a bearing 29 is disposed in the through hole 25a. Bearing 29 is shaft 2
1 is rotatably held in the radial direction RD. A stop ring 30 is connected to the shaft 21, and the stop ring 30 is connected to the shaft 21 in the thrust direction S.
D is prevented from moving.

Next, referring to FIG. 1 and FIG.
An operation example of 0 will be described in detail. When a current is supplied from the substrate 27 of FIG. 1 to the coil 26, the coil 26 generates a magnetic field, and the magnetic field forms a fixed magnetic path by the yoke 28. On the other hand, the magnetic field generated by the magnet portion 22 a also forms a fixed magnetic path by the rotor 23. Therefore, the magnetic field is confined in the region between the yoke 23 and the yoke 28, and the magnetic field leakage can be eliminated. When the coil 26 generates a magnetic field, the magnet portion 22a of the rotor 20A applies a rotational force to the rotor 20A, and the rotor 20A rotates around the shaft 21. Then, when the rotor 20A rotates, wind is generated from the blades 24, and for example, it is possible to cool electronic components constituting an electronic device such as a CPU having heat.

FIG. 3 is a view showing a manufacturing process of the fan motor 20 shown in FIG. 1. Referring to FIG.
0 will be described in detail. First, the yoke 23 having the yoke squeezed portions 23a and 23b is manufactured from galvanized steel. Then, the yoke 23 is inserted into the mold of the rotor housing 22, and the bond magnet flows into the mold (insert molding). Then Figure 3
As shown in FIG.
3 is embedded. At this time, since the yoke 23 is provided with the yoke throttle portions 23a and 23b, the yoke 23 does not come out of the rotor housing 22.

Next, as shown in FIG. 3B, the shaft 21 is fixed to the rotor housing 22 by press fitting. Then, as shown in FIG. 3C, the rotor housing 22 is magnetized to form a magnet part 22a. At this time, the magnet part 22a is formed so that the S pole and the N pole are alternately arranged, for example, in six poles. Finally, as shown in FIG. 1, the shaft 21 is inserted into the bearing 30, and the retaining ring 29 is connected. Thus, the fan motor 20 is completed.

According to the above embodiment, the fan motor 2
By integrally molding the blades 24 and the shaft press-fit portion with the bond magnet and insert-molding the yoke 23 for the rotor 20A of No. 0, it is possible to eliminate the bonding step, and reduce the cost and the defect rate. Further, by forming the yoke throttle portions 23a and 23b, it is possible to prevent the yoke from being separated from the rotor housing 22 or rotating with respect to the rotor housing 22.

Incidentally, the present invention is not limited to the above embodiment. As a material for forming the rotor housing 22, nylon-based ferrite has been described as an example, but a samarium-cobalt-based or neodymium-based bonded magnet can also be used. Although the galvanized steel is used as the material of the yoke 23, an iron plate or the like may be used.

[0024]

As described above, according to the present invention,
It is possible to provide a fan motor that can be manufactured inexpensively and efficiently with less defective products, and that can be reduced in size, weight, and thickness.

[Brief description of the drawings]

FIG. 1 is a sectional view showing a preferred embodiment of a fan motor according to the present invention.

FIG. 2 is a top view showing a rotor in the fan motor of the present invention.

FIG. 3 is a configuration diagram showing a manufacturing process of the fan motor of the present invention.

FIG. 4 is a sectional view showing an example of a conventional fan motor.

FIG. 5 is a top view showing the rotor in FIG. 4;

FIG. 6 is a sectional view showing an example of another conventional fan motor.

[Explanation of symbols]

20: fan motor, 20A: rotor, 20B
... stator, 21 shaft, 22 ... rotor housing, 22a ... magnet part, 23 yoke,
24 ... feather.

Claims (3)

[Claims] 1. A fan motor comprising: a stator having a coil for forming a magnetic field; and a rotor having a shaft rotatably held by the stator and fixed to a rotor housing, wherein the rotor comprises: It is integrally molded on the outer peripheral side of the rotor housing,
A blade for rotating to generate a wind, a magnet portion for forming a magnetic field integrally formed with the rotor housing on a surface of the rotor housing facing the stator, and an insert molding for the rotor housing. A yoke for forming a fixed magnetic path in a magnetic field generated by the magnet section. 2. A yoke restricting portion having a cylindrical shape is formed on each of an inner peripheral side and an outer peripheral side of the yoke so as not to fall off from the rotor housing toward a surface on which the magnet portion is formed. The fan motor according to claim 1. 3. The fan motor according to claim 1, wherein the magnet portion has S poles and N poles alternately formed along a circumference.