KR20030094647A - Spindle motor for optical disk driver - Google Patents

Abstract

PURPOSE: A spindle motor for an optical disk driver is provided to secure a stabilized driving characteristic by increasing adhesive strength between a turntable and a rotary shaft. CONSTITUTION: A housing(11') is formed in a tube shape, and to which a holder(12) having an open top surface and a closed bottom surface is inserted. A core(14) is mounted at an outside diameter part of the housing, and a bearing(13) is inserted into an inside diameter part. A rotor(17) includes a rotary shaft(15) rotatively inserted into the bearing, is combined with the rotary shaft to be rotated, and has magnets(18) arranged opposite to an outside diameter surface of the core. A turntable(20) has an assembling hole(21) at the center of a center part(22), and a rim of the center part is expanded to have a flat surface to let one surface of an optical disk(D) closely attached. An adhesive groove(30) is formed on an outer peripheral surface for partially containing an adhesive applied to the rotary shaft.

Description

Spindle motor for optical disk driver

The present invention relates to a spindle motor mounted as a driving source of an optical disk application device, and more particularly, to an optical disk driver spindle motor that can ensure stable driving characteristics even at high speed by improving the support strength of a turntable on which an optical disk is mounted. It is about.

In general, optical disks have the advantages of relatively high density recording and reproducibility and semi-permanent storage compared to magnetic recording tapes and LPs. There is a trend.

Such optical disk applications include a laser disk player, a compact disk player and a digital versatile disc. Among these optical disk applications, the size of the optical disk application is particularly small and portable. Although a compact disc player capable of being used is widely available, in recent years, a DVD having a larger storage capacity and the same size as a compact disc is rapidly spreading.

In such an optical disk application, one of the most important elements is a spindle motor for a driver for rotating a disk at high speed without flow, and in order to rotate the disk at high speed without flow, a disk with durability of the spindle motor is required. It can be said that it is important to maintain a stable balance according to the high-speed rotation of the turntable is seated.

1 is a cross-sectional view showing a spindle motor for an optical disk driver according to the prior art.

As shown in the figure, the spindle motor for the optical disc D driver includes a motor 100 that generates driving force, and a turntable 200 that is axially supported by the rotation shaft 150 of the motor 100 and rotates at high speed.

The motor 100 is provided with a burring portion 110 'which protrudes upward from the center of the plate 110 in a plate shape, and has a lower surface while the upper surface is opened under the burring portion 110'. Is a configuration in which the blocked cylindrical holder 120 is fitted. The metal bearing 130 is press-fitted into the inner space formed by the burring part 110 ′ and the holder 120, and a coil 140 wound around the outer circumferential end of the burring part 110 ′. ) Is fixedly mounted.

On the other hand, the rotating shaft 150 is inserted into the center of the bearing 130 is rotatably supported, the rotating shaft 150 is provided with a thrust washer 160 is fitted to the outer periphery of the lower end.

In addition, the rotor 170 is integrally coupled to the upper end of the rotating shaft 150 and rotated. The rotor 170 is provided in a downwardly open cap shape, and the inner end surface of the extended end of the rotor 170 is rotated. The cylindrical magnet 180 is fixed to face the outer diameter surface of the core 140 with an air gap.

In the motor 100 having such a configuration, when power is applied to the core 140 from the outside, the rotor 170 to which the magnet 180 is attached is formed by an electromagnetic force generated between the core 140 and the magnet 180. Is rotated, thereby the rotation shaft 150 coupled with the rotor 170 is supported by the bearing 130 to achieve a rotation at the same time.

On the other hand, the turntable 200 which is integrally rotated with the rotation shaft 150 of the motor 100 has a central portion 220 protrudes so that the optical disk (D) can be mounted on the upper end portion of the turntable 200 is one surface of the optical disk (D) It is provided in a form that is extended to have a flat surface in close contact, the central portion 220 is assembled hole 210 having an inner diameter corresponding to the outer diameter of the rotary shaft 150 so that the upper end of the rotary shaft 150 is inserted by the press-fitting This is the configuration to be formed.

Here, when the material of the turntable 200 is formed of a metal material, the assembly with the rotary shaft 150 is made by forced indentation or adhesive (b).

At this time, when assembling the turntable 200 and the rotary shaft 150 by force indentation, the inner diameter of the assembly hole 210 formed in the central portion 220 of the turntable 200 and the outer diameter of the rotary shaft 150 are forcibly interfitted. The assembly is done by forcing and press-fitting as much as possible.

However, in the case of assembling the turntable 200 and the rotation shaft 150 with each other by such forced indentation, excessive assembly force may be applied to the turntable 200 and the rotation shaft 150 during assembly to cause breakage of components. In addition, the concentricity between the turntable 200 and the rotational shaft 150 is changed, resulting in poor driving characteristics and rotation of the optical disc D mounted on the turntable 200 in an unbalanced state. The problem is caused.

On the other hand, when the turntable 200 is assembled to the rotary shaft 150 using the adhesive (b) turntable 200 in a state in which a certain amount of anaerobic adhesive (b) is applied to the upper outer diameter surface of the rotary shaft 150 The assembly is achieved by inserting the rotary shaft 150 into the assembly hole 210 of.

However, when assembling the turntable 200 and the rotating shaft 150 using the anaerobic adhesive (b), since the assembly hole 210 and the rotating shaft 150 of the turntable 200 are interfitted together. As a result, the adhesive (b) does not remain in the outer diameter portion of the rotation shaft 150, the adhesive (b) is pushed to the lower side of the turntable 200 to be cured. Therefore, since the adhesive (b) is locally located at the lower portion of the turntable 200 to exert an adhesive force, the engagement state between the turntable 200 and the rotation shaft 150 is not firm, so that the turntable 200 is rotated at high speed. It caused a problem that the flow from the rotating shaft 150 or easily separated by an external impact or vibration.

The present invention has been made to solve the above-mentioned conventional problems, and an object of the present invention is to reduce the excessive amount of indentation of the rotary shaft is pressed into the assembly hole of the turntable for the optical disk driver that can maintain a firm coupling state by the adhesive strength To provide a spindle motor.

1 is a cross-sectional view showing a spindle motor for an optical disk driver according to the prior art.

2 is a cross-sectional view showing a first embodiment of a spindle motor for an optical disk driver according to the present invention;

3 is a cross-sectional view showing a second embodiment of a spindle motor for an optical disk driver according to the present invention;

4 is a sectional view showing a third embodiment of a spindle motor for an optical disk driver according to the present invention;

<Explanation of symbols for the main parts of the drawings>

10 motor 11: plate

11 'housing 12: holder

13: bearing 14: core

15: shaft 16: washer

17: rotor 18: magnet

20 turntable 21 assembly hole

22: center portion 30, 31: groove

35: nulling surface D: optical disk

b: adhesive

Spindle motor for an optical disc driver according to the present invention for realizing the above object is provided in a tubular shape, the upper side is open and the bottom is fitted with a closed holder, the core is mounted on the outer diameter and the bearing is provided on the inner diameter. The inner diameter surface of the extension end has a cap shape in which the housing is press-fitted, a rotation shaft rotatably inserted into the bearing, and a cap shape in which the outer circumferential end is downwardly extended and coupled to the upper end of the rotation shaft. A rotor having a magnet disposed to face each other; An assembly hole is formed at the center of the central portion which protrudes so that the upper end of the rotating shaft is press-fitted, and the turntable extends to have a flat surface so that one surface of the optical disk is in close contact with the turntable; It is provided on the target outer peripheral surface of the rotary shaft pressed into the assembly hole of the turntable, characterized in that it comprises an adhesive groove for receiving a portion of the adhesive applied to the rotary shaft.

In one preferred feature of the present invention, the adhesive groove is a groove formed to a depth of 0.1mm or less along the outer circumferential surface of the rotating shaft.

In another preferred aspect of the present invention, the adhesive groove is a groove which is formed in a plurality of intervals, the upper and lower intervals along the outer peripheral surface of the rotation shaft.

Another preferred feature of the present invention is that the adhesive groove is a knurled surface formed by knurling.

According to another preferred feature of the present invention, the housing is provided in which the outer periphery of the lower end is fitted into a hole provided in a plate-shaped plate.

In another preferred aspect of the present invention, the housing is integrally formed by burring in a plate-shaped plate.

Hereinafter, a preferred embodiment of a spindle motor for an optical disk driver according to the present invention will be described with reference to the accompanying drawings.

2 is a cross-sectional view showing a first embodiment of a spindle motor for an optical disk driver according to the present invention.

As shown in the figure, the spindle motor for the optical disc driver includes a motor 10 which greatly generates rotational force by power supply, and a turntable 20 to which the optical disc D is mounted while rotating integrally with the motor 10. It consists of.

The motor 10 includes a stator composed of a plate 11 having a housing 11 ', a bearing 13, and a core 14, and a rotating shaft 15, a rotor 17, and a magnet 18. It is roughly classified as a rotor.

That is, the stator includes a housing 11 'having a tubular shape, and the housing 11' at this time has a tubular shape at the center of the plate 11 having a predetermined thickness, as shown in the drawing. It may be formed integrally by the burring process projecting upward or provided with a tubular housing 11 'but not shown in the drawing and fitted into a hole formed in a plate-shaped plate. have.

Thus, the housing 11 'formed integrally with the plate or provided by the fitting structure has an upper surface open to the lower side of the open both ends thereof, and the bottom surface of the housing 11' is fitted with the cylindrical holder 12 fitted therein. It is a structure that forms a space.

Here, the metal bearing 13 is press-fitted and fixed in the inner space formed by the housing 11 'and the holder 12, wherein the core is wound around the outer circumferential end of the housing 11'. 14 is fixedly mounted, wherein the core 14 is configured to be selectively powered from the outside.

On the other hand, the rotating shaft 15 of one element constituting the rotor is inserted into the center of the bearing 13 is rotatably provided, the thrust washer 16 is fitted to the lower end of the rotating shaft (15).

At this time, the rotor 17 is integrally coupled to the upper end of the rotary shaft 15 to form a rotation, the rotor 17 at this time is provided in the shape of a cap (cap) with the outer peripheral end is extended, extending As the inner diameter surface of the end, a cylindrical magnet 18 in which N-S poles are alternately magnetized is fixed. Such a magnet 18 faces an air gap with the outer diameter surface of the core 14 described above. Is placed.

The turntable 20 is configured to be integrally rotated by being coupled to the upper end of the rotation shaft 15 of the motor 10. As shown in the drawing, the turntable 20 has a configuration in which the central portion 22 protrudes in the up and down directions. The main surface of the center portion 22 is provided in a shape extending outward.

In more detail with reference to the drawings, the turntable 20 has an assembling hole 21 penetrated so that the center portion 22 protrudes up and down, and the upper end of the rotating shaft 15 can be pressed into the center thereof. The peripheral portion of the central portion 22 is configured to extend to have a flat surface so that one surface of the optical disk D can be in close contact.

When the power source is applied to the core 14 in the spindle motor for the optical disk driver configured as described above, the rotor 17 and the rotating shaft 15 are connected to the bearing 13 by the electromagnetic force generated between the core 14 and the magnet 18. Rotation is integrally supported by the support, and at the same time, the turntable 20 coupled to the upper portion of the rotation shaft 15 is also integrally rotated.

This configuration is similar to the structure of the spindle motor for optical disk drivers. However, the present invention has the most prominent feature to reduce the amount of indentation between the turntable 20 and the rotary shaft 15 to increase the bonding force by the adhesive while improving the assemblability to ensure stable driving characteristics.

That is, the present invention has a predetermined depth to accommodate a certain amount of adhesive when the adhesive is applied to the target outer diameter surface of the rotary shaft 15 is pressed into the assembly hole 21 of the turntable 20 as shown in FIG. And to form an adhesive groove having a width.

In more detail, the rotation shaft 15 is formed to be assembled by press-fitting with respect to the inner diameter of the assembly hole 21 of the turntable 20, the outer periphery is a certain amount when applying the adhesive (b) Adhesive groove (b) to form a space that can accommodate the adhesive (b), that is the configuration is provided with a groove (30).

At this time, the groove 30 is provided on the outer diameter portion of the rotation shaft 15 corresponding to the assembly hole 21 of the turntable 20, as shown in the drawing, is formed in the shape of a ring-shaped groove along the main surface It is preferred that the depth be molded to a depth of 0.1 mm or less while having a width of approximately 1 mm or less.

According to the present invention configured as described above, when the adhesive (b) is applied to the target outer peripheral surface of the rotating shaft 15 corresponding to the assembling hole 21 of the turntable 20, and pressed into the assembly hole 21, the rotating shaft ( The adhesive b applied to the outer diameter surface of 15 is pushed out of the assembling hole 21 by close contact between the rotating shaft 15 and the assembling hole 21, but the grooves of the rotating shaft 15 30, the adhesive (b) of a certain amount remains, thereby exhibiting the adhesive force. Therefore, the rotary shaft 15 and the turntable 20 can maintain a firmly coupled state by the adhesive force of the indentation and the adhesive (b).

On the other hand, the adhesive (b) remaining on the groove (30) of the rotation shaft 15 has a narrow space between the rotation shaft 15 and the turntable (20) of the stabilizer which is one of the components contained in the adhesive (b) The faster the movement, the higher the curing speed. That is, due to the narrow space between the rotating shaft 15 and the turntable 20, the anion and cation generated between these two objects are increased, so that the stabilizer constituting the adhesive (b) moves quickly, and the curing speed is normal. It has a very fast curing speed compared to the case of exposure in the middle.

Therefore, the groove 30 is formed in the outer diameter portion of the rotating shaft 15 in the spindle motor for the optical disk driver configured as described above, thereby adding the adhesive strength by the adhesive b to the rotating shaft 15 and the turntable 20. It is possible to significantly reduce the amount of indentation between the assembling holes 21 of the (). Therefore, it is possible to minimize breakage and shaft twist between the rotary shaft 15 and the turntable 20 caused by excessive pressure input.

Meanwhile, the present invention shows a configuration in which an adhesive groove is formed on the outer circumference of the rotating shaft 15, but the present invention is not limited thereto, and a predetermined amount of adhesive b may be stored between the rotating shaft 15 and the turntable 20. The formation position and the size of the groove may be variously changed if it is possible to increase the bonding force by the adhesive (b) in addition to the press-fitting by providing a space that can be.

As an example, as shown in FIG. 3, a plurality of grooves 30 and 31 are formed at regular intervals up and down in the upper outer diameter portion of the rotating shaft 15, or as shown in FIG. It may be provided in the form of a knurled surface 35 is formed by.

In addition, although not shown in the drawings, the adhesive groove, that is, the groove formed in the outer diameter portion of the rotation shaft 15 may be formed in the assembly hole 21 of the turntable 20.

On the other hand, the above-described embodiment is merely described one preferred embodiment of the present invention, the scope of application of the present invention is not limited to such, and can be changed as appropriate within the scope of the same idea. For example, the shape and structure of each component shown in the embodiment of the present invention can be modified.

The spindle motor for an optical disc driver according to the present invention constructed and operated as described above can increase the adhesive strength between the turntable and the rotating shaft, thereby ensuring stable driving characteristics, and in particular, by improving the assembly strength by the adhesive, Since the indentation amount between the rotating shafts can be managed more relaxedly than before, it provides the advantage of increased design and processing freedom.

Therefore, the generation of defective products in the assembly process between the turntable and the rotary shaft can be greatly reduced, and the quality of the product can be improved.

Claims (6)

A housing which is provided in a tubular shape and has an upper surface open at a lower side thereof and a holder closed at a bottom thereof, a core mounted on an outer diameter portion, and a bearing press-fitted on an inner diameter portion; The rotating shaft is rotatably inserted into the bearing and the cap is rotated integrally coupled to the upper end of the rotary shaft and the outer peripheral end portion is extended downwardly, and the magnet is disposed opposite the outer diameter surface of the core with a gap on the inner diameter surface of the extension end. A rotor having a; An assembly hole is formed at the center of the central portion which protrudes so that the upper end of the rotating shaft is press-fitted, and the turntable extends to have a flat surface so that one surface of the optical disk is in close contact with the turntable; Spindle motor for an optical disc driver, characterized in that provided on the target outer peripheral surface of the rotary shaft pressed into the assembly hole of the turntable, the adhesive groove for receiving a portion of the adhesive applied to the rotary shaft. The spindle motor of claim 1, wherein the adhesive groove is a groove formed to a depth of 0.1 mm or less along the outer circumferential surface of the rotating shaft. The spindle motor of claim 1, wherein the adhesive groove is a plurality of grooves formed at upper and lower intervals along an outer circumferential surface of the rotating shaft. The spindle motor for an optical disc driver according to claim 1, wherein the adhesive groove is a knurled surface formed by knurling. The method of claim 1, wherein the housing, Spindle motor for an optical disk driver, characterized in that the outer periphery of the lower end is fitted into the hole provided in the plate-shaped plate. The spindle motor for an optical disc driver according to claim 1, wherein the housing is integrally formed by burring in a plate-shaped plate.