KR20130038651A - Spindle motor - Google Patents

Abstract

The present invention relates to a spindle motor. The spindle motor according to the present invention forms a space portion between the rotating shaft and the rotor case, and accommodates the upper end of the bearing and the bearing holder in the space portion, thereby enabling the expansion of the shaft support portion supporting the rotating shaft to the spindle motor. Shaft vibration can be easily improved due to slimming, and the life of the spindle motor can be extended.

Description

Spindle Motors {SPINDLE MOTOR}

The present invention relates to a spindle motor.

The spindle motor maintains a constant contact section between the bearing and the rotating shaft and can easily maintain the rotation characteristics as the rotating shaft is rotated, such as a hard disk drive (H1DD) and an optical disk drive (ODD). It is widely used as a driving means of a recording medium requiring high speed rotation.

Such a spindle motor typically includes an armature, a rotor including a magnet that generates electromagnetic force between the armature, and a stator rotatably supporting the rotor, and by an electromagnetic force generated between the armature and the magnet. As the rotor rotates, the recording medium is easily driven.

On the other hand, the spindle motor is required to be slim in accordance with the trend of thinning and lightening of electronic products to which it is applied, and a situation in which a model is developed based on this is being made. However, as the spindle motor has been slimmer, problems have also been drawn. Representatively, shortening of the life due to unstable rotation of the rotor can be mentioned.

That is, in order to slim the spindle motor, as shown in FIGS. 1 and 2 of (Patent Document 1), the distance between the rotor case constituting the rotor and the base plate constituting the stator should be narrowed as much as possible. There is a structural limit that the length of the bearing supporting the shaft is only about half of the rotation axis.

This results in a decrease in the length of the shaft support for supporting the rotary shaft. Therefore, the conventional spindle motor designed to be slim, including the above (Patent Document 1), the rotor has to rotate unstable, the life of the spindle motor is shortened.

KR 2011-0037234 A

Accordingly, the present invention is to solve the problem that the shaft support for supporting the rotating shaft is reduced due to the slimming of the spindle motor to increase the unstable rotation of the rotor, that is, the amount of shaft shaking, thereby shortening the life of the spindle motor.

SUMMARY OF THE INVENTION An object of the present invention is to provide a spindle motor capable of easily improving shaft shaking.

In order to achieve the above object,

The present invention is a rotating shaft;

A rotor including a rotor case installed on an upper portion of the rotating shaft;

A stator including a bearing holder having a bearing supporting the rotation shaft;

An armature comprising a core provided in the bearing holder; And

A space portion formed between the rotating shaft and the rotor case to accommodate the upper end of the bearing and the bearing holder;

And a control unit.

The space portion according to the present invention is formed by a first refraction portion formed by upper refraction of the inner diameter of the rotor case, a second refraction portion formed by horizontal refraction of the first refraction portion, and a third refraction portion formed by refraction of the second refraction portion It is characterized by.

Bearing holder according to the invention is characterized in that the extension is formed on the top.

According to the present invention, a space portion for accommodating the upper end of the bearing and the bearing holder is formed between the rotating shaft and the rotor case, so that the shaft support for supporting the rotating shaft can be easily expanded, thereby improving shaft shaking. It has the effect of extending the life of the slim spindle motor.

On the other hand, the space portion is formed by refracting the rotor case, there is no need to use a separate subsidiary material for forming it has the effect of preventing the increase in manufacturing costs.

1 is a cross-sectional view showing an embodiment of a spindle motor according to the present invention.
Figure 2 is an enlarged cross-sectional view showing the main portion of FIG.
3 is an experimental data comparing and experimenting a spindle motor and a conventional spindle motor according to the present invention.

Hereinafter, embodiments of the present invention will be described in detail with reference to the accompanying drawings.

As shown in FIG. 1, the spindle motor 1 according to the present invention includes a rotating shaft 10, a rotor 20 including a rotor case, and a bearing for supporting the rotating shaft 10. And a stator 30 including a bearing holder, an armature 40 including a core provided in the bearing holder 32, and between the rotating shaft 10 and the rotor case 21. The space part 50 is included.

The rotating shaft 10 is implemented in such a way as to be inserted into the center of the bearing 31 embedded in the bearing holder (32). Therefore, the bearing 31 axially supports the rotating shaft 10 inserted in the central portion, so that the whole thereof functions as the shaft supporting portion 31a.

In addition, a stopper 32a is provided inside the bearing holder 32 in which the bearing 31 is embedded, and the rotor 20 rotates by intermittently lowering the lower portion of the rotating shaft 10 through the stopper 32a. To prevent injury.

The rotor 20 is implemented in such a way as to press the rotor case 21 on the top of the rotating shaft (10). The rotor case 21 is a kind of circular plate, and a magnet for rotating the rotor by generating an electromagnetic force with the armature 40 is provided therein, and a recording medium, that is, a magnetic disk or an optical disk, is provided thereon. A clamp 23 for resiliently fixing is installed.

Therefore, the rotor 20 is rotated by the electromagnetic force generated between the magnet 22 and the armature 40, thereby rotating or recording the elastically fixed recording medium to the clamp 23, to record or reproduce data It will be possible.

The stator 30 installs a bearing holder 32 on an upper portion of the base plate 33, and embeds a bearing 31 for supporting the shaft 10 in the bearing holder 32. Will be implemented. In this case, a substrate 34 may be installed on the base plate 33, and in this case, external power is supplied to the armature 40 through the substrate 34.

The outside of the bearing holder 32 in which the bearing 31 is embedded is provided with a core 41 to install an armature 40 between the rotor 20 and the stator 30. At this time, a coil (Coil) is wound around the core 41. Since the coil 41 is well known in the related art, a detailed description thereof will be omitted.

Meanwhile, as described above, the spindle motor 1 includes a space 50 formed between the rotation shaft 10 and the rotor case 21. As shown in FIG. 2, the space part 50 has an upper end of the shaft support part 31a supporting the rotation shaft 10, that is, the bearing 31 and the bearing holder 32 in which the bearing 31 is embedded. By accommodating, the shaft support part 31a is provided to expand.

Here, to accommodate the upper end of the bearing holder 32 together with the bearing 31 through the space portion 50 is that the oil, etc. placed between the bearing 31 and the rotating shaft 10 is scattered to the outside. This is to prevent. Unlike the bearing 31, the bearing holder 32 extends a part of the upper end to form an extension part 32b, and then accommodates the extension part 32b in the space 50.

In this way, the space portion 50 accommodating the upper end of the bearing 31 and the bearing holder 32 is formed by refracting the rotor case 21, and thus the space portion 50 without using a separate subsidiary material. ) Can be formed.

In other words, the first refraction portion 21a is formed by upper refraction of the inner diameter of the rotor case 21, and the second refraction portion 21b is formed by horizontal refraction of the first refraction portion 21a, and then the second refraction portion 21b is formed. The lower portion of the refraction portion 21b is formed to form the third refraction portion 21c, thereby forming a space portion between the rotation shaft 10 and the rotor case through the first refraction portion 21a and the second refraction portion 21b. 50).

In addition, the rotor case 21 is press-fitted to the rotation shaft 10 through the third refraction portion 21c. The first, second and third refraction portions 21c may be formed by the rotor case 21. It can be formed through the press working or injection molding in the process of manufacturing.

In this case, terms such as “first” and “second” are used to distinguish one component from another component, and the component is not limited by the terms.

Therefore, the upper end of the bearing 31 and the bearing holder 32 can be inserted into the space 50 formed by the deflection of the rotor case 21, so that the shaft support part 31a can be easily expanded. Will be.

Due to the expansion of the shaft support part 31a through the space part 50, the spindle motor 1 according to the present invention forms the length of the bearing 31 as 4 mm, in the case of a conventional slim spindle motor. The length is designed by 3 mm.

3 is an experimental data comparing the lifespan of the spindle motor 1 according to the present invention having a bearing 31 having a length of 4 mm and a spindle motor to which a conventional 3 mm bearing is applied. It is showing possible.

1-spindle motor 10-axis of rotation
20-rotor 21-rotor case
21a-first refraction 21b-second refraction
21c-third refraction 30-stator
31-bearing 31a-shaft support
32-bearing holder 32a-stopper
32b-extension 40-armature
41-core 50-space

Claims (3)

A rotating shaft;
A rotor including a rotor case installed on an upper portion of the rotating shaft;
A stator including a bearing holder in which a bearing for supporting the rotating shaft is embedded;
An armature comprising a core provided in the bearing holder; And
A space portion formed between the rotating shaft and the rotor case to accommodate the upper end of the bearing and the bearing holder;
Spindle motor comprising a.
The method according to claim 1,
The space portion is formed by a first refraction portion formed by upper refraction of the inner diameter of the rotor case, a second refraction portion formed by horizontal refraction of the first refraction portion, and a third refraction portion formed by refraction of the second refraction portion. Spindle motor made.
The method according to claim 1 or 2,
The bearing holder is a spindle motor, characterized in that the extension is formed on the top.

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